Repositório Digital - IPEN/SP: Recent submissions

  • IPEN-DOC 27036

    PEREZ, CLARICE F.A.; SAHYUN, ADELIA ; FREITAS, KENIA A.M.. Study on the protection planning actions and response to nuclear or radiological emergency. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 1783-1787.

    Abstract: Nuclear or Radiological emergencies can have as a consequence the rise of Deterministic effects, in the population involved, and/or Stochastic effects due to their doses. In these situations, protective actions need to be done in order to keep the doses in the affected population below the levels of deterministic effects and protective actions that might reduce the risk of stochastic effects should be adopted, minimizing the doses to reasonably achievable levels. This work presents a comparative study between the publication of IAEA Safety Series 109 and the document of the International Atomic Energy Agency GSG-2 "Criteria for Use in Preparedness and Response for a Nuclear or Radiological Emergency" regarding the effective dose value system to be used as a basis to trigger protection actions in the Planning and Response to Nuclear or Radiological Emergencies that can reduce the risk of stochastic effects.

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  • IPEN-DOC 27035

    TEIXEIRA, MARIA I. ; CALDAS, LINDA V.E. . Optical stimulated luminescence from citrine for high-doses dosimetry. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Abstract... The International Radiation Protection Association, 2016. p. 1343-1343.

    Abstract: In the sterilization of medical and pharmaceutical products, food and flower preservation, and treatment of electrical cables and al-treatments of different materials is used the irradiation process by highdoses because it presents advantages varies.Several Brazilian stone samples were already studied at IPEN for use in radiation dosimetry, using the techniques of thermoluminescence (TL), optical absorption (AO) and optically stimulated luminescence (OSL). Different kinds of glasses and sand from Brazilian beaches were studied at IPEN and showed favorable characteristics for their use for high-dose dosimetry. The possibility of using semi-precious stones from Brazilian as topaz, amethyst and jasper, and jade samples from different parts of the world, have been studied and tested at IPEN, using the technique of thermoluminescence. The objective of this work was to study citrine samples for application in high-dose dosimetry, using the OSL technique. The thermal treatment for reutilization of the materials was 300oC during 1h in an unsealed oven. The samples were irradiated using a Gamma Cell-220 system of 60Co (dose rate of 1.47 kGy/h), with doses from 50 Gy up to 300 kGy. The reproducibility of the OSL response presented a maximum variation coefficient of 5.7%. The lower detection limit was obtained as 350 mGy for the citrine pellets. The results show that the OSL detectors based on citrine may be useful for high-dose dosimetry in industrial processes and in the sterilization process of materials in hospitals.

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  • IPEN-DOC 23677

    CARNEIRO, J.C.G.G. ; ALVES, A.S. ; SANCHES, M.P. ; RODRIGUES, D.L. ; LEVY, D.S. ; SORDI, G.M.A.A. . Basic characterization of a radioactive facility and evaluation of risk agents. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 892-899.

    Abstract: This is an exploratory and descriptive study with qualitative and quantitative approaches to investigate the basic characterization of a Brazilian radioisotope production facility through ample knowledge of the workplace, workforce, task performed and identification of present risk agents in labor environment. The studied sample was composed by 102 workers distributed in eight work processes. Data were collected from April 2013 to July 2014 by applying questionnaire forms and complemented by interviews and observations. The descriptive statistical analysis included ANOVA test and non-parametric tests, among others. For the purpose of this study, there was adopted a significance level of 5% (p<0.05). The analysis of socio-demographic variables demonstrated that male gender predominated in total sample (74.5%) and the mean age of the workers was (51.8 ± 1.7) years. The largest percentage of the responders (70.6%) was technician-level workers. Regarding task-related exposure, there was considered that all groups presented the same exposure profile. At the workplace, there were identified 17 risk agents, including physical, chemical, biological, ergonomic and accident risks. The workforce was categorized into 3 risk groups according to relative frequency distribution of the occupational risks. Among the sixteen qualitative variables studied at the workplace, only three of them did not demonstrate relative frequency. The only variable that showed association with the three risk groups was the possibility of the contact with ionizing radiation. The study provided an overview of the perception of occupational risk at the facility. According to the results obtained by statistical analysis, most of the qualitative variables presented statistically significant association (p<0.001) related to the occurrence of occupational risks. Even though the workers may be potentially exposed to different risk agents, the ionizing radiation was the main physical risk factor observed in this facility.

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  • IPEN-DOC 27011

    KUAHARA, LILIAN ; CORREA, EDUARDO ; POTIENS, MARIA da P. . Activimeter response behaviour analysis related to well depth. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Abstract... The International Radiation Protection Association, 2016. p. 756-756.

    Abstract: The activimeter, instrument used to radionuclide activity measure, consist primarily of a well type ionization chamber coupled to a special electronic device. Its response, after calibration, is shown in units of the activity quantity (Becquerel or Curie). It also has a special holder designed to accommodate all kinds of syringes and vials containing the radiopharmaceuticals. Many factors influence the response of an activimeter such as the volume of the sample, its position inside the activimeter well and the geometry of the vials. The idea of this study is to find the better position inside the well to get the best activity values, positioning the holder in different profundity, simulating a clinical procedure. The reference activimeter used was the Secondary Standard NPL-CRC radionuclide calibrator, traceable to the National Physical Laboratory (NPL), England, taking as reference the depth of 400 mm. Two other activimeters were tested: Capintec, CRC-15BT model with the depth of 170 mm and one CRC-25R model with depth of 257 mm. They all belong to the Instrument Calibration Laboratory of IPEN, São Paulo, Brazil. The measurements were made using three radioactive check sources: Co-57, Ba-133 and Cs-137. Sources readings were taken at various depths inside the ionization chamber well. The results shown maximum variation of 14.28% for Co-57, 11.27% to Ba-133 and 8.8% to Cs-137. All measurements were compared with those values found for the reference depth in each activimeter. The variation found show the necessity of include this kind of determination in all quality control programs that are applied to an activimeter used by a Nuclear Medicine Service.

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  • IPEN-DOC 27010

    POTIENS JUNIOR, ADEMAR ; COSTA, NATHALIA ; CORREA, EDUARDO ; SANTOS, LUCAS ; VIVOLO, VITOR ; POTIENS, MARIA da P. . Tandem KAP meters calibration parameters by Monte Carlo Simulation using reference RQR radiation qualities. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Abstract... The International Radiation Protection Association, 2016. p. 702-702.

    Abstract: The Kerma-area product quantity can be obtained by measurements carried out with a kerma-area product meter (KAP) with a plane-parallel transmission ionization chamber mounted on the X ray system. It is the integral of the air kerma over the area of the X ray beam in a plane perpendicular to the beam axis. This quantity has been important to establish the diagnostic reference levels (DRLs) all over the word. In this work the MCNP5 code was used to calculate the imparted energy in the air cavity of KAP meter and the spatial distribution of the air collision kerma in entrance plan of the KAP meter. From these data, the air kerma-area product (KAP) and the calibration coefficient for the KAP meter were calculated and compared with those obtained experimentally. The X-ray tube was easily modelled as well the complete tandem calibration set up was possible. The spectra of the diagnostic radiology RQR reference qualities measured were used as a source definition in the input card for the Monte Carlo simulation. The clinical KAP meter calibration coefficients were obtained experimentally and by Monte Carlo simulation. The differences between those values were about 2%, except for RQR 10 (5.45%). The uncertainties in Monte Carlo simulation were less than 0.5% in all cases and the FOM (Figure of Merit) was constant for a number of histories of 1 million.

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  • IPEN-DOC 27064

    SAHYUN, ADELIA ; GHOBRIL, CARLOS N.; PEREZ, CLARICE F.; SORDI, GIAN M. . The evaluation of the real alpha value in Brazil and its projection until the year 2050. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Abstract... The International Radiation Protection Association, 2016. p. 444-444.

    Abstract: The real evolution of the alpha value in Brazil has been performed three times in 1993 and 2000 making use of the procedure advised by ICRP and in 2004 making use of the procedure recommended by the IAEA. In both, the first two papers were made various projections for the coming years until 2025. Because of the great social and economic crisis in which the country (Brazil) is going, we decided to reassess the alpha value of our country and compare it with the projections of the two previous papers. Therefor e, we decided to make a dollar correction from that time to the current dollar, comparing the purchasing power from that time to the current. This procedure has shown us the great gap of value in use and that the actual value should be two to three times h igher. By GDP per capita, we could calculate the alpha value updated to various countries including the European Union and compare them with the official value currently in use. In conclusion, we believe that all countries that adopt an alpha value should upgrade it to the present day.

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  • IPEN-DOC 27063

    SORDI, GIAN M. . Comments on the General IAEA Safety Requirements - Part 3 - and suggestions for the next publications. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 381-383.

    Abstract: The international recommendations in question are described 52 requirements specified from chapter 2 to 5. The first chapter states that the number of fundamental safety principles has been increased form 3 to 10. To implement these requirments, the IAEA mentions 14 main parties but it is not clear which party is responsible for each of the fundamental safety principles. Chapter 2 presents 5 general requirements for protection and safety and makes it clear the responsibilities and competence of the government and regulatory body. ; but the responsibilities and competence of the other 12 principal parties reported in requeriment 4 are not clear. Chapter 3, which includes 37 requirements, is the most extensive and deals with planned exposure situations. Due to its extension, chapter 3 is left for a future paper, in case my comments are considered of some value by the principal parties involved. Chapter 4, with 4 requirements, deals with emergency exposure situations; and in chapter 5, the 6 requirements are about existing exposure situations. As to the requirements exposed in chapters 1, 2, 4 and 5 I have verified that the responsibilities and competence of the government and the regulatory body are clearly specified, which is not true for the other 12 principal parties. It is concerning this specific matter that I have made comments and suggestions. I also discuss the matters that are not under the responsibility of the radiological protection services but of other parties. Could the radiation protection service as a whole or in part be delegated to others, including the attributions of registrants or licensees?

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  • IPEN-DOC 27062

    SORDI, GIAN M. . Comments on the General IAEA Safety Requirements - Part 3 - and suggestions for the next publications. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 298-303.

    Abstract: The international recommendations in question are described 52 requirements specified from chapter 2 to 5. The first chapter states that the number of fundamental safety principles has been increased form 3 to 10. To implement these requirments, the IAEA mentions 14 main parties but it is not clear which party is responsible for each of the fundamental safety principles. Chapter 2 presents 5 general requirements for protection and safety and makes it clear the responsibilities and competence of the government and regulatory body. ; but the responsibilities and competence of the other 12 principal parties reported in requeriment 4 are not clear. Chapter 3, which includes 37 requirements, is the most extensive and deals with planned exposure situations. Due to its extension, chapter 3 is left for a future paper, in case my comments are considered of some value by the principal parties involved. Chapter 4, with 4 requirements, deals with emergency exposure situations; and in chapter 5, the 6 requirements are about existing exposure situations. As to the requirements exposed in chapters 1, 2, 4 and 5 I have verified that the responsibilities and competence of the government and the regulatory body are clearly specified, which is not true for the other 12 principal parties. It is concerning this specific matter that I have made comments and suggestions. I also discuss the matters that are not under the responsibility of the radiological protection services but of other parties. Could the radiation protection service as a whole or in part be delegated to others, including the attributions of registrants or licensees?

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  • IPEN-DOC 23678

    LEVY, DENISE S. ; SORDI, GIAN M.A.A. ; RODRIGUES, DEMERVAL L. ; CARNEIRO, JANETE C.G. . Enhancing communication on Radiological Protection throughout Brazil. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 284-290.

    Abstract: This paper focus on the potential value of Information and Communication Technologies (ICTs) to enhance communication on Radiological Protection throughout Brazil. The servers processing power added to the technology of relational databases allow to integrate information from different sources, enabling complex queries with reduced response time. It is our objective to provide radioactive facilities a complete repository for research, consultation and information on radiological protection in an integrated and efficient way. This webbased project works informatization of Radiological Protection Programs according to the positive tree published by AIEA in its Safety Series No. 102, the most generic and complete tree for an appropriate and effective radiation protection program. Up to this moment, the website counts on concepts, definitions and theory about optimization and monitoring procedures, interrelating information, currently scattered in various publications, in order to meet both Brazilian and international recommendations. The project involves not only the collection and interrelationship of existing information in the several publications, but also new approaches from some recommendations, such as potential exposures. Only few publications develop expressively the issue and, even though they provide fundamental theory, there is still lack of knowledge of failure probabilities, which currently constitutes a broad research field in radiological protection. This research proposes the development of fault trees and the analysis of different scenarios, suggesting paths to quantify probabilistically the occurrence of potential exposures, as well as probabilities to reach a certain level of dose. It is our target to complete the system in a near future, including other relevant issues, such as safe transport of radioactive materials, emergency response, radioactive waste management and decommissioning, among others. We believe the use of information technology for the radiological protection programs shall contribute greatly to provide information to Brazilian radioactive facilities throughout the country, spreading information to as many people as possible, minimizing geographic distances and stimulating communication and development.

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  • IPEN-DOC 27060

    SAHYUN, ADELIA ; GHOBRIL, CARLOS N.; PEREZ, CLARICE F.; SORDI, GIAN M. . Some suggestions to adequate the IAEA Safety Standards Series No. 49 according to the General Safety Requirements Part 3 from IAEA. In: CLEMENT, CHRISTOPHER (Ed.); VALENTIN, JACK (Ed.); OGINO, HARUYUKI (Ed.); FOOTE, DEVON (Ed.); REYJAL, JULIE (Ed.); OMAR-NAZIR, LAILA (Ed.) INTERNATIONAL CONGRESS OF THE INTERNATIONAL RADIATION PROTECTION ASSOCIATION, 14th, May 9-13, 2016, Cape Town, South Africa. Proceedings... The International Radiation Protection Association, 2016. p. 224-227.

    Abstract: At that time of publication SSR49 two exposure situations were considered, namely: practices and interventions, with Naturally Occuring Radioactive Material (NORM) being considered as intervention exposures but acknowledging that some natural sources can have exposures resulting from practices. In the Ba sic Safety Standards (BSS) the exposure situations have been categorised as planned, emergency and existing. These three situations necessitate an update of SSR No.49 since NORM fits in the existing situation, i.e one in which the doses already exist and should be reduced. To reduce the doses will create radioactive waste that must be either treated or stored. This scenario raises a problem of defining the dividing line between existing and planned situations. The point of transistion from one situation to the other needs to be clarified in order to establish the necessary controls for an existing situation whilst providing the necessary controls needed for the planned situation. For the latter planned situation several questions arise as to whether certain requirements can be exempted and under what circumstances. This paper will examine what the authors consider most important in more detail with some suggestions made for further consideration.

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  • IPEN-DOC 27059

    GARCIA, V. ; SOLE, S.V. ; BOIANI, N.F. ; ROSA, J.M.; BORRELY, S.I. . Evaluation of toxicity and color reduction of Reactive dye Yellow 160 and Red BG-3B, and textiles effluents after treatment by electron beam. In: SETAC LATIN AMERICA BIENNIAL MEETING, 12th, September 7-10, 2017, Santos, SP. Abstract... 2017. p. 110-110.

    Abstract: Textile effluents are always collored due to the amount of dyes lost during dieying processes. The low biodegradability and high solubility makes these compounds (reactive dyes) difficult to be enough removed by conventional treatment processes. The objective of the present study is to assess toxicity of Reactive dye Yellow - 160 and Red BG-3B as well as raw effluents containing such dyes. Acute toxicity tests were carried out with reference aquatic organisms: Vibrio fischeri bacteria and Daphnia similis microcrustaceans. After this, the effluent is also submitted to EBI treatment (irradiation at electron beam accelerator) for reducing color, with 0.5 kGy to 20 kGy doses. 100% of daphnids survived at 1g.L-1 of RY-160, and for Red BG-3B (C=0.564 g.L-1) EC 50% (48h) = 69.0 ± 0.66 . Raw textile effluent with dye RY-160 resulted in EC 50% lower than 2% for both organisms (D. similis EC 50% (48h) = 1.74 ± 0.53 and 0.6 ± 0.29, V. fischeri (15 min). For raw textile with Red BG-3B: D. similis EC 50% (48h) = 6.73 ± 0.72. The EBI treatment was effective for color removal, efficiency superior to 90% at 10 kGy. The data demonstrated the importance of evaluating not only dyes but also the effluent, since it has several additives that contributed to the high toxicity.

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  • IPEN-DOC 27058

    MARTINI, G. ; VIVEIROS, W.; FRANÇA, D.D.; QUINAGLIA, G.; RAIMUNDO, C.C.; LOPES-FERREIRA, M.V.; ROGERO, S.O. ; ROGERO, J.R. . Fish Embryo Toxicity Test (FET) to evaluate atrazine effects. In: SETAC LATIN AMERICA BIENNIAL MEETING, 12th, September 7-10, 2017, Santos, SP. Abstract... 2017. p. 83-83.

    Abstract: Surface water samples from São Paulo state were collected to perform Bioluminescent Yeast Estrogen Screen (BLYES) and chemical analyses (LC-MS/MS). Results showed environmental concentrations of atrazine from 2 to 43 ng L-1 on chemical analyses. Some studies have been performed to evaluate toxic effects on non-target organisms (fish) using herbicides such as Atrazine, a moderately toxic compound classified as an endocrine disrupting chemical (EDC) that can affect reproduction of several aquatic organisms with a compromise of vitellogenin production. To determine toxicity on embryonic stages of fish to different environmental chemicals and waste water, Fish Embryo Toxicity Test (FET) was designed using Danio rerio as model specie on this test, according to OECD 236 or ISO 15088 protocols, however these protocols observe only acute toxicity based on endpoints such as coagulated eggs, nondetachment of the tail, lack of heart beating and lack of somite formation. Some abnormalities can be recorded after the exposure on FET test but they are not considered as endpoint, neither any other compromised biomarker by EDC action. In order to evaluate the possibility of using these chronic endpoints and to verify if those environmental concentrations of atrazine are ecologically relevant, compromising reproductive aspects, FET test using Danio rerio were performed to assess lethal concentrations, sublethal concentrations and vitellogenin quantification after atrazine exposure. Occurrence of morphological abnormalities (microcephaly, spine curvature, edema, reduced size) and mortality of the embryos were determined exposing 20 fertilized eggs to atrazine concentrations from 2 to 64 mg L-1. The LC50 and EC50 were obtained after 96 hours of exposure. Organisms that survived each concentration were frozen to further vitellogenin quantification. Preliminary average concentrations obtained (LC 50; 96h= 48.15 mg L-1 and EC 50; 96h= 27 mg L-1) were considerably higher than concentrations observed on environmental samples. Therefore, surface water concentrations would not cause mortality or deformity in fish emphasizing the necessity to observe possible effect on vitellogenin concentration. Data will be analyzed and compared with the environmental concentration of atrazine to stablish the potential application of vitellogenin as endpoint on FET test.

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  • IPEN-DOC 27056

    GIMILIANI, G.T. ; FONTES, R.F.; ABESSA, D.M.. Modeling the dispersion of endocrine disruptors in the Santos Estuarine System (São Paulo State, Brazil). In: SETAC LATIN AMERICA BIENNIAL MEETING, 12th, September 7-10, 2017, Santos, SP. Abstract... 2017. p. 64-64.

    Abstract: Estrogens are hormones responsible for growth and reproduction. They are naturally synthesized by animals and humans alike. Xenoestrogens are identical to natural hormones, but they are manmade and used as oral contraceptives. Xenoestrogens are a specific group of drugs found in domestic wastewater and some environmental matrices. These compounds remain after conventional sewage treatment and, consequently, affect both the environment and non-target aquatic organisms. In this study, we used the Delft3D hydrodynamic model to estimate the amount of both natural and synthetic estrogens that have been released in the Estuarine System of Santos and São Vicente and the Santos Bay. The data on flow from the sewage treatment plants and on average concentrations of natural and synthetic estrogens released in aquatic environments were obtained from the literature. The results of the modeling showed higher concentrations of estrogens in the estuarine waters of the Largo Pompeba region, the São Vicente Canal, and the Santos Bay, which are regions that receive greater inflows of domestic sewage. The results also suggest that higher concentrations of estrogenic compounds are expected to be found in areas with higher levels of salinity.

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  • IPEN-DOC 27055

    CUNICO, P.; FUNGARO, D.A. ; KUMAR, A.. Toxicity studies applied to evaluate the modified zeolites adsorbent for treating copper-complex dyes from simulated dyehouse wastewater. In: SETAC LATIN AMERICA BIENNIAL MEETING, 12th, September 7-10, 2017, Santos, SP. Abstract... 2017. p. 35-36.

    Abstract: Textile dyes occur in wastewaters in different concentrations due to their poor fixation to fabrics. Even at low concentrations, textile dyes can cause waste streams to become highly colored. Aside from their negative aesthetic effects, certain textile dyes have been shown to be toxic, and in some cases, these compounds are carcinogenic and mutagenic. Zeolite synthesized from fly and bottom ashes and modified with hexadecyltrimethylamonium (ZMF and ZMB, respectively) were used as adsorbent to remove dyes - Solophenyl Navy and Solophenyl Turquoise and their hydrolyzed forms Solophenyl Navy Hydrolyzed and Solophenyl Turquoise Hydrolyzed, respectively, from simulated textile wastewater. The purpose of the research was to use bioassays with Lemna minor, Ceriodaphnia dubia and Chironomus tepperi to determine the acute and chronic toxicity of these dyes before and after adsorption process. The acute results indicated C. tepperi showed to be less sensitive when compared with other test organisms, showing values of 48hLC50 70.8 and 211 mgL-1 for SN and ST. On the other hand, C. dubia showed to be very sensitive to the dyes tested (48hLC50 1.25; 54.5; 0.78 and 2.56 mgL-1 for SN, ST, SNH and STH), while L. minor presented response for higher concentration of the dyes, as chlorosis, loss of roots, reduction of the size and etc., showing values of EC50 of 18.9; 69.4; 10.9 and 70.9 mgL-1 for SN, ST, SNH and STH). Chronic tests with C. tepperi showed changes in survival, growth, development and gender differences for SN and ST dyes. After adsorption treatment with ZMF the acute effects were substantially reduced for both dyes and their hydrolyzed forms, showing absence of toxicity after treatment. However, the treatment with ZMB showed no difference and/or increased toxicity in some cases. Toxicity Identification Evaluation testes were realized and showed the baseline acute effects were substantially reduced after treatment with Ethylenediaminetetraacetic acid, showing the most of the toxicants in this study are cations metals. These experimental results suggest both dyes, raw and hydrolyzed, are toxic and their removal are necessary.

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  • IPEN-DOC 27054

    FERNANDES, I.; SOUSA, E.P.; GASPARRO, M.R.; CATHARINO, M.G. ; CERAVOLO, M.; CAMARGO, J.; LINS, C.G.. Sensitivity of Nitokra sp copepod exposed to UVA and UVB filters used in commercial formulations. In: SETAC LATIN AMERICA BIENNIAL MEETING, 12th, September 7-10, 2017, Santos, SP. Abstract... 2017. p. 65-66.

    Abstract: Large discharges of pollutants released in the marine environment have as final destination the sediment, affecting the quality and biodiversity. Pharmaceuticals and personal care products (PPCPs) are lipophilic and poorly biodegradable, with potential for bioaccumulation and persistence in the environment. Compounds from commercial sunscreens are found in the oceans, because they are often used by people. This study evaluated the acute effect of UVA and UVB filters - Benzophenone-3 (BZ- 3), Octyl Salicylate (OS) and Octyl Methoxycinnamate (OMC), detected in commercial sunscreens, performing the test both in a mixture as isolated – using Nitokra sp copepod and the method described in ISO14669:1999. When exposed to the water soluble fraction of the UV filters mixture, the mean of LC50-96h was 11.47 %, corresponding to 190 mg.L-1 of BZ-3, 150 mg.L-1 of OS and 230 mg. L-1 of OMC, while the isolated UV filter showed a tendency to increased lethality.The tests were performed in parallel with the reference substance DSS, and were within the acceptability limits of the LECOTOX LC50-96h = 7.76 (3.98-11.55) mg.L-1 DSS. It was concluded that the test organism and the method used were suitable for the tests with the commercial UV filters mixture and that, although the filters used are fatsoluble, there are bioavailable concentrations in the environment. The tested mixture caused deleterious effects to Nitokra sp. in concentrations lower than ANVISA (2006) allows, therefore more research is needed.

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  • IPEN-DOC 27053

    PUSCEDDU, F.; SANTOS, D.R.; MORENO, B.B.; GUIMARÃES, L.; CORTEZ, F.S.; PEREIRA, C.D.S.; CHOUERI, R.B.; SANTOS, A.R.; ROGERO, S.O. ; ROGERO, J.R. ; CESAR, A.. Marine sediment contamination in a subtropical zone (Santos Bay, Brazil): pharmaceuticals, personal care products and cocaine. In: SETAC LATIN AMERICA BIENNIAL MEETING, 12th, September 7-10, 2017, Santos, SP. Abstract... 2017. p. 64-64.

    Abstract: Although the continuous input of domestic sewage in coastal areas has been reported, few data are available about the presence of pharmaceuticals and personal care products (PPCPs) in coastal environments of South America. The aim of this study was to determine the environmental concentration of PPCPs and cocaine in sediments from Santos Bay (Brazil), a degraded coastal area due to urban and industrial pollution. A sediment sample, collected at five points around the Submarine Sewage Outfall of Santos, was analyzed by liquid chromatography-tandem mass spectrometry (LCMS/ MS) and 35 compounds were investigated. The presence of five pharmaceuticals (caffeine, carbamazepine, diclofenac, fluoxetine and ibuprofen), one personal care product (triclosan), and one illicit drug (cocaine) was evidenced. Considering the absence of information about the occurrence of PPCPs and illicit drugs in marine sediments of tropical and subtropical areas of South America, the data reported here subsidize the \nassessment of environmental risks of such substances in coastal zones.

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  • IPEN-DOC 27052

    CAMARGO, J.; SOUSA, E.P.; CATHARINO, M.G. ; GASPARRO, M.R.; ABESSA, D.M.; FERNANDES, I.; LINS, C.G.; VASCONCELLOS, M.B. . Lysosomal stability in oysters Crassostrea sp. from three different populations from the coast of São Paulo, Brazil. In: SETAC LATIN AMERICA BIENNIAL MEETING, 12th, September 7-10, 2017, Santos, SP. Abstract... 2017. p. 39-39.

    Abstract: Coastal zones continuously receive inputs of contaminants, which greatly affect its quality. Biological effects resulting from environmental pollution are complex and have not been properly estimated by chemical analysis and toxicity tests. A reliable form to assess the environmental quality consists of analyzing organisms exposed to constant, complex and diffuse sources of contamination. The appropriate use of biomarkers in sentinel organisms may provide an estimate of the potential risk associated with contamination. This study aims to evaluate if different levels of potential contamination affect differently the stress responses in oysters from three sites along the coast of São Paulo state. The physiological condition of oysters Crassostrea sp. from Cananéia (reference site), Santos and Bertioga was studied by analyzing the lysosomal membrane stability in haemocytes, measured using the neutral red retention time (NRRT) assay. Adult organisms were collected in spring (August, September, and October/2016) and autumn (April and May/2017). During the spring, the times of retention of the neutral red dye were similar in oysters from different sites and the reference area (p > 0.05). Interestingly, an uncommon red tide occurred along the coast of the state mainly affecting Cananéia, which may have influenced the reduction of the NRRT for oysters from this region. Such biological events (algal blooms) are more likely to occur at this time of year due to the typical climatic conditions, and may have the potential to even the adverse effects of pollution on distinct bivalve populations subject to different levels of contamination. During the autumn campaign, organisms from both contaminated sites (Santos and Bertioga) showed significant reduction in the mean NRRT relative to the reference site (p < 0.05). A previous study in the same region (Catharino et al., 2015) observed that in both seasons the oysters from Cananéia had a higher NRRT than the oysters from the other two sites. Overall, the NRRT were lower in the present study. These results may be due to the exposure of the organisms to pollutants, since lysosomes are organelles that absorb a wide variety of organic and inorganic substances. However, further investigations are required and being carried out to confirm this hypothesis.

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  • IPEN-DOC 27050

    ARAUJO, ELAINE C. ; ANDRADE, IZABEL da S. ; MACEDO, FERNANDA de M. ; CORREA, THAIS ; SALANI, MARIA H.G. de A. ; COSTA, RENATA F. da; RAMOS, SERGIANA dos P.; MARQUES, MARCIA T.A. ; LOPES, DANIEL S.; GUARDANI, MARIA L.G.; LANDULFO, EDUARDO ; GUARDANI, ROBERTO. Correlation study between air quality data and the Lidar system in Cubatao, Sao Paulo. In: SANTOS, JANE M. (Ed.); ANDRADE, MARIA de F. (Ed.); ALBUQUERQUE, TACIANA T.A. (Ed.) COMMUNITY MODELING AND ANALYSIS SYSTEM SOUTH AMERICA CONFERENCE, 3rd; AIR QUALITY CONFERENCE BRAZIL, August 28-31, 2017, Vitória, ES. Proceedings... Vitória, ES: Fundação Espírito-santense de Tecnologia, 2017. p. 175-177.

    Abstract: We present here the results of two methods with a scanning multiwavelength elastic lidar system and Beta Ray method (CETESB) realized in an industrial area. The objective is a comparer of these two methods to identify fixed sources of aerosol and to monitor plume dispersion. The results of the two aligned techniques indicate that can provide information on the concentration, spatial and temporal distribution of aerosol.

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  • IPEN-DOC 27045

    KOSKINAS, M.F. ; YAMAZAKI, I.M. ; DIAS, M.S. . Standardization of 59Fe by 4π(PC)β-γ software coincidence system. In: INTERNATIONAL CONFERENCE ON RADIONUCLIDE METROLOGY AND ITS APPLICATIONS, 20th, June 8-11, 2015, Vienna, Austria. Abstract... 2015. p. 127-127.

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  • IPEN-DOC 27043

    SUGAHARA, TARCILA; MOMTORO, FABIANO E.; MARTINS, GISLENE V.; MASSI, MARCOS; REIS, ADRIANO G. dos ; REIS, DANIELI A.P.. SiC/Cr thin films deposited by HiPIMS on Ti-6Al-4V used as protective coating in creep tests. In: CONGRESSO BRASILEIRO DE APLICAÇÕES À VACUO NA INDÚSTRIA E NA CIÊNCIA, 38.; WORKSHOP DE TRATAMENTO E MODI CAÇÃO DE SUPERFÍCIES, 3., 21-24 de agosto, 2017, São José dos Campos, SP. Resumo expandido... 2017. p. 157-158.

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  • IPEN-DOC 27041

    REIS, ADRIANO G. dos ; REIS, DANIELI A.P.; ABDALLA, ANTONIO J.; COUTO, ANTONIO A. ; BRIGUENTE, LUCIANA A.N. da S.; MARCHETTO, LUIZ R.O.; LOPEZ, JAVIER O.. Microstructural evaluation of maraging 300 steel laser treated. In: CONGRESSO BRASILEIRO DE APLICAÇÕES À VACUO NA INDÚSTRIA E NA CIÊNCIA, 38.; WORKSHOP DE TRATAMENTO E MODI CAÇÃO DE SUPERFÍCIES, 3., 21-24 de agosto, 2017, São José dos Campos, SP. Resumo expandido... 2017. p. 46-47.

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  • IPEN-DOC 27040

    CAVALCANTE, F. ; PECEQUILO, B.R.S. ; LEONARDO, L. . Activity concentrations of natural and artificial radionuclides in feline dry food. In: INTERNATIONAL CONFERENCE ON ENVIRONMENTAL RADIOACTIVITY, September 21-25, 2015, Thessaloniki, Greece. Abstract... 2015.

    Abstract: Natural radiation exposure is an inherent condition to all living species, once radionuclides from the 238U and 232Th chain can nearly be found in all places. Information on radionuclides concentration and exposure levels, from natural and anthropogenic sources are absolutely necessary to investigate the possible effects that ionizing radiation can induce. These can be very different depending on the organism considered and the exposure pathway. In recent decades, the exposure of non-human species to ionizing radiation has been specially considered and investigated (ICRP, 2014) by a vast number of scientists and organizations, once they differ widely from the exposure of human beings. Brazil holds the second largest cat and dog population in the world, consuming over 2 million tons of feed every year. The country also stands out for its production of pet food that produced 2.4 million of tons of feed in 2014, representing the world’s second largest industry. A novel study regarding the radionuclide content in different dog and cat food is being developed since 2013 and preliminary results have been presented by Cavalcante, F. and Pecequilo (2014), for selected dry dog food. The present study presents an evaluation of the radionuclide and radioactivity content of different brands of dry cat food, commonly found in local markets in the city of Sao Paulo, Brazil. Thirteen different samples were crushed into powder and kiln dried before tightly sealed in 100 mL HDPE flasks, with a plan screw cap and bubble spigot. These samples, after resting for 30 days to ensure secular equilibrium, were placed in an extended range coaxial germanium detector (Canberra XtRa GX4020 detector) for 150 ks and the acquired spectra were analyzed with the InterWinner 6.0 software (InterWinner, 2004). The natural radionuclides considered were 238U, 232Th and 40K, the anthropogenic radionuclides investigated were 60Co, 131I, 137Cs and 134Cs. The results for the considered artificial radionuclides have shown activity concentration values below the detector’s MDA (Minimum Detectable Activity), as in Table 1. The concentrations of natural radionuclides ranged from 1.12 ± 0.29 Bq/kg to 3.77 ± 0.36 Bq/kg for 226Ra; from 1.48 ± 0.40 Bq/kg to 6.27 ± 0.78 Bq/kg for 232Th and from 216.8 ± 11.2 Bq/kg to 361.7 ± 16.8 Bq/kg for 40K, as shown in Figure 1. The results suggest that the samples evaluated have no contamination of artificial radionuclides and the natural radionuclides concentration will not contribute to significant absorbed dose by their ingestion. Therefore, the authors conclude that these studied brands carry no radiological risk for the animals ingesting them.

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  • IPEN-DOC 27034

    VARCA, GUSTAVO H.C. ; BARROS, JANAINA A.G. ; BATISTA, JORGE G.S. ; SASOUNIAN, RAFAELA; SILVA, GUSTAVO T.M.; ZAMARION, VITOR M.; KATTI, KATTESH V.; LUGAO, ADEMAR B. . Protein crosslinking onto gold nanoparticles by gamma radiation. In: DUDALA, JOANNA (Ed.); CIECHANOWSKI, MAREK (Ed.) INTERNATIONAL CONFERENCE ON DEVELOPMENTS AND APPLICATIONS OF NUCLEAR TECHNOLOGIES, September 10-13, 2017, Kraków, Poland. Abstract... Kraków, Poland: AGH University of Science and Technology - Faculty of Science and Applied Computer Science, 2017. p. 43-43.

    Abstract: The use of gold nanoparticles for diagnosis and treatment of cancer has received great attention over the last decade. Particularly, the possibility to use them for theranostics has increased the interest in the medical and scientific community. Weak technological aspects are related to the low biological affinity and non-specific toxicity. The use of albumin is of highlighted interest as albumin has been associated to inorganic particles to overcome biopharmaceutical challenges, including site-specific delivery and other biopharmaceutical advantages. The current work addresses the use of radiation and its effects over the crosslinking of bovine serum albumin onto gold nanoparticles. The idea of crosslinking the albumin onto gold surface aims to improve the stability of the protein layer onto gold nanoparticles in biological systems. Gold nanoparticles were synthesized by green technology using resveratrol and albumin capping was performed by physiosorption followed by irradiation at doses of 2.5, 5, 7.5, 10 and 15 kGy using 60Co as a radioactive source. Nanoparticle properties were assessed by dynamic light scattering, UV/Vis spectrophotometry and transmission electron microscopy. Protein crosslinking was monitored by fluorescence studies and stability of the nanoparticles was evaluated by zeta potential and titration with sodium chloride. The results evidenced the formation of a protein layer onto gold nanoparticles and revealed a protein crosslinking by means of bityrosine as a function of irradiation dose. Stability was considerably improved by the presence of the protein layer and the crosslinked protein layer.

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  • IPEN-DOC 27033

    OLIVEIRA, JUSTINE P.R. de ; OLIVEIRA, MARIA J.A. de ; SILVA, ISABELA C. da ; VARCA, GUSTAVO H.C. ; LUGAO, ADEMAR B. . Influence of different gamma radiation doses on PVA/gelatin based scaffolds. In: DUDALA, JOANNA (Ed.); CIECHANOWSKI, MAREK (Ed.) INTERNATIONAL CONFERENCE ON DEVELOPMENTS AND APPLICATIONS OF NUCLEAR TECHNOLOGIES, September 10-13, 2017, Kraków, Poland. Abstract... Kraków, Poland: AGH University of Science and Technology - Faculty of Science and Applied Computer Science, 2017. p. 27-27.

    Abstract: The present work aimed to study the influence of different radiation doses on a polymer blend at cryogenic and room temperature by means of crosslinking formation, pore size, morphology, topography and mechanical properties. The scaffold was prepared based on two formulations, one composed by gelatin (7%, w/w) and PVA (5%, w/w), and the second by gelatin (10%, w/w) and PVA (5%, w/w). The formulations were separately solubilized in distilled water and heated up to 80 ºC under constant stirring for 1 hour. Posteriorly, both blends were disposed in circular glass moulds. Half of samples was frozen for at least 24 h and then irradiated at 15, 25 and 50 kGy. The other half was cooled at 4 ºC for at least 24 h and then irradiated using the same doses. After irradiation both sample groups were frozen and freeze dried. The scaffold was characterized in terms of structure and morphology by mechanical assays, differential scanning calorimetry, scanning electron microscopy, optical coherence tomography and infrared spectroscopy. In addition, platelet adhesion and release, and cytotoxic assays were also performed. Samples irradiated at 15 kGy presented pore size diameter of around 1.4 μm and porosity of 54%, while samples irradiated at 25 kGy, presented pore size diameter of around 1.1 μm and porosity of 49%. Optical coherence tomography showed that gelatin control samples presented more superficial degradation as irradiation dose increased, while PVA control sample presented higher integrity, indicating that this polymer is less sensitive to gamma radiation. The system presented suitable mechanical properties and the platelet adhesion and release assays showed that the scaffold presented adequate pore size range to host and release the platelets, and non-cytotoxic to platelets, featuring adequate properties to be applied as dressing for wound treatments.

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  • IPEN-DOC 27031

    MUNHOZ JUNIOR, A.H.; MIRANDA, L.F.; SILVA, L.G.A. ; OLIVEIRA, M.O. de; ANDRADES, R.C.; GOMES, G.C.. Use of gamma-alumina nanoparticles for drug delivery system for releasing acyclovir. In: INTERNATIONAL CONFERENCE ON DIFFUSION IN SOLIDS AND LIQUIDS, 12th, June 26-30, 2016, Split, Croatia. Abstract... DSL Conference, 2016. p. 154-155.

    Abstract: The sol-gel process is a method for preparing porous ceramics, vitreous and crystalline materials from molecular precursors. In this process, a lattice of oxide compounds is made through reaction of inorganic materials in aqueous solution. The sol-gel process may be used to produce nanoparticles of pseudoboehmite, which are employed in drug delivery systems, production of nanocomposites and in the synthesis of gamma-alumina [1,2,3]. The firing of pseudoboehmite produces pure gamma-alumina [4,5]. The use of nanoparticles in drug delivery systems is advantageous because it prevents repeated doses and also decreases the amount of drug intake, which not only enhance the therapeutic effect, but also reduces the risks of plasma concentration reaching toxic levels. The use of synthetic nanoparticles have attracted great interest for applications in drug delivery systems. Pure gamma-alumina obtained from pseudoboehmite is a synthetic aluminum compound with excellent adsorbent properties. In this work, gamma-alumina was obtained through pseudoboehmite firing to be used for in vitro release of acyclovir. The gamma-alumina was characterized by X-ray diffraction (XRD), Differential Thermal Analysis (DTA), Thermogravimetry Analysis (TG), Scanning Electron Microscopy (SEM) using secondary electron detector and EDS detector. The release profile was obtained by UV/Vis spectroscopy for in vitro analysis. The results indicate gamma-alumina is appropriate for release of acyclovir.

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  • IPEN-DOC 27030

    MIRANDA, LEILA F. de; GOULART, LEID J.P.; SILVA, LEONARDO G. de A. e ; DONADON, ALEXANDRE C.; YAMASAKI, FABIO Y.; MUNHOZ JUNIOR, ANTONIO H.. Characterization of polystyrene nanocomposites containing nanoparticles of pseudoboehmite obtained by sol-gel process. In: INTERNATIONAL CONFERENCE ON DIFFUSION IN SOLIDS AND LIQUIDS, 12th, June 26-30, 2016, Split, Croatia. Abstract... DSL Conference, 2016. p. 153-154.

    Abstract: Polymer nanocomposites are hybrid materials in which inorganic substances of nanometric dimensions are dispersed in a polymeric matrix. These substances have high surface area allowing a better interaction with the polymeric matrix and consequently promote changes in the physical properties of the final composite with small additions of the same. The preparation of nanocomposites with polymer matrix allows in many cases to find a relationship between a low cost due to the use of lower amount of charge, reaching high level of performance. In this work, were obtained polystyrene nanocomposites with pseudoboehmite synthesized by the sol-gel process with different concentrations of pseudoboehmite using octadecylamine as a coupling agent. The nanocomposites were prepared by the melt intercalation technique and characterized by differential thermal analysis, thermogravimetric analysis, heat deflection temperature, Vicat softening point, mechanical and rheological tests. The results showed an increase in the thermal properties, hardness and tensile strength values and decrease in the melt index, impact resistance and tensile elongation, showing the interaction of the filler with the polymer matrix.

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  • IPEN-DOC 27029

    HEILMAN, S. ; SILVA, L.G.A. . Silver and titanium nanoparticles used as coating on polyurethane catheters. In: INTERNATIONAL CONFERENCE ON DIFFUSION IN SOLIDS AND LIQUIDS, 12th, June 26-30, 2016, Split, Croatia. Abstract... DSL Conference, 2016. p. 150-150.

    Abstract: Silver nanoparticles have been used in the medical area due to their remarkable antimicrobial properties [1]. In this sense titanium dioxide nanoparticles obtained by the sol-gel method were used as coating of catheters for subsequent impregnation of silver nanoparticles with gamma irradiation and electron beam at 25 and 50 kGy [2]. This work aimed to study the use of the silver nanoparticles and titanium dioxide as coating of polyurethane Central Venous Catheter (CVC) for antimicrobial activity. Furthermore the amounts of titanium and silver present in the coated catheters had been evaluated by Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES). Therefore the Raman spectrometry was used to identify the polymorph of titanium oxide, rutile.

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  • IPEN-DOC 27028

    MIRANDA, F.; RODRIGUES, D.; NAKAMATO, F.Y.; FRAJUCA, C.; SANTOS, G.A.; COUTO, A.A. . Microstructure and properties of composite WC-8(Co, Ni): effect of the addition of SiC. In: INTERNATIONAL CONFERENCE ON DIFFUSION IN SOLIDS AND LIQUIDS, 12th, June 26-30, 2016, Split, Croatia. Abstract... DSL Conference, 2016. p. 99-100.

    Abstract: The WC-based cemented carbides, also called hard metals, are a family of composite materials consisting of carbide ceramic particles embedded in a metallic binder. They are classified as metal matrix composites (MMCs) because the metallic binder is the matrix that holds the bulk material together [1]. WC based composites are used in applications where a good combination of hardness and toughness are necessary [2]. It is usual to add more components as the tungsten carbide in a binder (Co, Ni) to build the microstructure. The hardness for the cemented carbides based on nickel, because of the addition of reinforcements SiC nano-whisker increases significantly [3]. In this work, the SiC was researched as an additional component for composite WC-8(Co, Ni). Four mixtures were prepared with SiC content ranging from 0 to 3.0 wt%. These mixtures were pressed (200 MPa) and green samples with 25.2 mm of diameter and 40g were produced. Sintered were carried out in Sinter-HIP furnace (20 bar). Two sintering cycles were investigated with 1380 and 1420°C, and the sintering time considered was 60 minutes. The relative density, hardness, linear and volumetric shrinkage were determined. Microstructural evaluation was performed by optical microscopy and scanning electron microscopy (SEM-FEG). The results showed that the addition of SiC promoted higher densification and grain growth. The hardness was higher for samples with SiC, so solid solution hardening of the binder was more effective than WC grain growth.

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  • IPEN-DOC 27027

    REIS, A.G. ; REIS, D.A.P.; ABDALLA, A.J.; OTUBO, J.; COUTO, A.A. . An in situ high-temperature X-ray diffraction study of phase transformations in maraging 300 steel. In: INTERNATIONAL CONFERENCE ON DIFFUSION IN SOLIDS AND LIQUIDS, 12th, June 26-30, 2016, Split, Croatia. Abstract... DSL Conference, 2016. p. 95-95.

    Abstract: The phase transitions in the maraging 300 steel were studied using high temperature X-ray diffractometry. Maraging are ultra-high resistant steels with Ni-Co-Mo-Ti presenting a broad range of application in key areas such as nuclear and aerospace industries [1]. Prolonged high temperature exposure would lead to the formation of equilibrium austenite and ferrite phases [2]. Solution annealed maraging 300 steel was continuously heated at a 10 ºC/min rate from ambient temperature until 900 ºC and X-Ray measurements were done at 25, 400, 500, 600, 650, 700, 800 and 900 ºC. Dilatometric curve at the same heating rate and temperature range were performed and the results were compared with high temperature X-Ray diffraction. The martensite to austenite transformation and vice-versa could be detected by both techniques, although the precipitation could be detected only by dilatometry, associated to low volume of precipitates to be detected by X-Ray diffraction. The effect of austenite reversion at 600ºC was also studied after at 1, 2, 3 and 4 hour of exposure, showing that the amount of reverted austenite is proportional of time exposure at high temperature.

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  • IPEN-DOC 27025

    FONSECA, DANIELA P.M. da ; MONTEIRO, WALDEMAR A. . Analysis by optical microscopy and x-ray diffraction of composite Cu-Cr-Ag-Al2O3 synthesized using powder metallurgy. Acta Microscópica, v. 26, Supplement B, p. 278-279, 2017.

    Abstract: The use of Nature's materials in favor of human beings has been present in its daily life for a long time, copper and its alloys have been used in function of the high thermal and electrical conductivity, good mechanical properties, resistance to corrosion, ease of fabrication and also by the high value of scrap [1]. Metal alloys can also be combined with other classes of materials in order to obtain new properties, superior to the original alloy, this union of two or more materials forms a composite [2]. The studied composite has a ternary metal alloy (copper, chromium and silver) as a matrix and a ceramic oxide (alumina) as the reinforcing phase. The addition of chromium, silver and small amounts of finely dispersed metal oxides in copper improves their mechanical properties and increases the operating temperature, causing little loss of conductivity. A possible application of this composite is in electrical contacts, electronic devices that break the passage of current in electrical circuits [1]. The objective of this study was the microstructural characterization by optical microscopy and X-ray diffraction of the composite Cu-Cr-Ag-Al2O3 processed by powder metallurgy. The samples used were fabricated in laboratory scale of 25 mm diameter, 3,5 mm  ℎ  4,0 mm of height and 6,5 g of mass, with the following chemical compositions: (a) 85% Cu – 15% Al2O3; (b) 90% Cu – 5% Cr – 2% Ag – 3% Al2O3; (c) 90% Cu – 5% Cr – 5% Al2O3; (d) 90% Cu – 7% Cr – 3% Al2O3; (e) 85% Cu – 5% Cr – 5% Ag – 5% Al2O3; (f) 90% Cu – 5% Cr – 3% Ag – 2% Al2O3; (g) 90% Cu – 3% Cr – 7% Al2O3. In order to obtain the samples, the powders were weighed on a precision balance (according to each composition), mixed manually and cold-compacted in uniaxial press with 450 MPa pressure and sintered in an EDG furnace under 10-3 torr of mechanical vacuum and 650 °C in 6 h. The samples were prepared metallographically and observed in an optical microscope, the micrographs indicated coalescing of the copper particles and other metallic elements and formation of porosity (figure 1). The X-ray diffraction data were collected for samples (a) and (e) using graphite monochromator, copper tube, 25º ≤ 2θ ≥ 90º and Δ2θ = 0,02, from the diffractograms the mean crystallite size (𝐷) and microdeformation (𝜖) were calculated using the Williamson-Hall graphical method where the approximate line has a linear coefficient equal to 1/𝐷 and the angular coefficient is equal to 4𝜖/𝜆 [3]. In both samples were identified the expected phases, in agreement with the composition, and an undesirable phase of copper oxide (figure 2). The Williamson-Hall method was not used for all phases because it requires the identification of at least three peaks. Optical micrographs indicated presence of porosity inside the structure and partial homogeneity, due to the non-dissolution of the elements involved in the metal alloy, it is necessary to do further special thermal treatments. In some samples, a third phase was recognized, whose composition demands microanalyses to be properly identified. Through the diffractograms it was possible to identify the phase of copper oxide possibly coming from the sintering stage, this phase is not desirable or this composite because it negatively influences its electrical and mechanical properties. The Williamson-Hall method obtained a straight line with good correlation and suitable values of mean crystallite size and microdeformation for the copper phase.

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  • IPEN-DOC 27024

    DIAS, RENAN A.F. ; MONTEIRO, WALDEMAR A. . Microstrutural evolution of nickel-based superalloy processed by Equal-Channel Angular Pressing (ECAP). Acta Microscópica, v. 26, Supplement B, p. 71-72, 2017.

    Abstract: The present work shows the microstructural (under optical microscopy) and Vickers hardness evolution of a nickel-based superalloy Inconel 600 (alloy 600) before and after deformed by Equal-Channel Angular Pressing (ECAP) that significantly modified the alloy microstructure and, consequently, its strength. Alloy 600 is an austenitic nickel-based superalloy with 72% nickel, 14-17% chromium and 6-10% iron and it is commonly used in structures and components that work in aggressive environments. The grain size plays a significant role in the mechanical properties in this alloy; so, it is important to understand how processing techniques modify the microstructure of the material. In fact, ECAP is a processing technique involving the application of severe plastic deformation (SPD) used in the manufacture of metals and alloys with ultra-fine grains (UFG) and therefore with extraordinary combinations of both high strength and high ductility [1]. For the research, alloy 600 rods, supplied by Multialloy, with 8 mm diameter, were heat treated at 1200 °C for 6 h (solution), as shown in Figs. 1a and 1b, to achieve a larger grain size. The generated products were machined to the final dimensions of the specimen (6 X 6 X 25 mm) shown in Fig. 1c and then processed by ECAP, at room temperature using route A, in a D2 tool steel die, whose angles Φ and Ψ are 120° and 0° (Fig. 1d). Samples were pressed repetitively through a total of three passes, the microstructural aspect of the samples after each pass are shown in Figs. 2 and 3 with different magnifications. Metallographic preparations were made in the transverse, longitudinal and normal directions, TD, LD and ND of each sample. Sanding step with grit 320, 600 and 1200 were used. Polishing steps included 3 um- and 1 um-diamond paste and 0.05 um-alumina suspension and finally they were etched for optical examination using Marble’s etchant (10 g CuSO4, 50 ml HCl and 50 ml H2O). The micrographs were taken with OLYMPUS optical microscope model BX51M, with magnifications of 100x and 200x. The hardness tests were conducted in a Buehler Micromet 2103 microdurometer in the LD of the samples. For each measurement, a load of 500 g was applied for 15 s. Five separate measurements were taken on each sample at randomly selected points and then averaged. In Figs. 1a and 1b, it is possible to see only 1 phase, a solid solution of Ni-Cr-Fe, a coarsed grain structure and annealing twins. There are slight changes in the microstructure after the first pass, some strain marks are seen. After the second and third passes the microstructure shows highly deformed grains, deformation and transition bands. The values of hardness (Tab. 1) show an increase after each pass. In summary, (1) the micrographs analysis shows all the transformations from an annealed state to a highly-deformed state; (2) the grains are yet elongated after 3 passes and possibly do not show an expected UFG structure; (3) deformation twinning is revealed and is possible to see strain marks, deformation and transition bands; (4) the hardness values increased due to the high strain imposed to the alloy.

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  • IPEN-DOC 27023

    LIMA, CASSIO A. ; CORREA, LUCIANA; ZEZELL, DENISE M. . Infrared spectroscopy determining the biochemical changes in premalignant skin lesions submitted to photodynamic therapy. In: WORKSHOP FTIR SPECTROSCOPY IN MICROBIOLOGICAL AND MEDICAL DIAGNOSTICS, 11th, October 19-20, 2017, Berlin, Germany. Abstract... 2017.

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  • IPEN-DOC 27021

    RODRIGUES, PATRICIA F. ; WHITEMAN, DAVID; VANABLE, DIMITRIUS; DEMOZ, BELAY; WALKER, MONIQUE; LANDULFO, EDUARDO . Comparison of the hygroscopic behavior of aerosols obtained by Raman LIDAR and nephelometry: the NASA Discover-AQ experience. In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: The hygroscopic behavior of aerosols is of great interest in the recent decades because of the importance in computing the radiative forcing of aerosols in the energy balance of the planet. The last report of the IPCC in 2013 shows that the uncertainty associated to the interactions between aerosols and clouds is high, and more research in this area is needed in order to give more information about the indirect effect of aerosols. The LIDAR (Light Detections and Ranging) is a technique that can be used to study the hygroscopic growth of aerosols under varying relative humidity conditions, and the main advantage of the technique is the possibility of studying the hygroscopicity next to the saturation in an unperturbed atmosphere. During the NASA Discover-AQ in 2011, a Raman LIDAR operated at the Howard University in Beltsville, United States, at the same time a nephelometer inside an airplane was sampling the same aerosol population. Then, the hygroscopic growth factor of the aerosols was computed using both instruments, and the results are now being compared. In this work, the result obtained by the LIDAR will be shown and compared to the nephelometer results obtained by Ziemba et al (2013) for 05 July 2011. The different methodologies adopted are explained and discussed. The good agreement between both instruments shows LIDAR is a promising technique in this field of study.

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  • IPEN-DOC 27020

    GUERRERO-RASCADO, JUAN L.; LOPES, FABIO J.S. ; ALADOS-ARBOLEDAS, LUCAS; HOELZEMANN, JUDITH J.; FERNANDEZ, JOSE H.; LEME, NEUSA P.; LANDULFO, EDUARDO . On the meteorological scenarios and main air mass paths at the LALINET Natal station (Northeastern Brazil). In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: To continue the effort in understanding the role of aerosol particles on continental scale, the Latin American Lidar Network (LALINET) [Guerrero-Rascado et al., 2014] will spread its activities to the North-eastern part of South America in the near future. A new LALINET station will be deployed at Natal (Rio Grande do Norte, Brazil, 5.84º S, 35.20º W) with the aim of characterizing the transcontinental transport of aerosol particles from Africa to South America, mainly Saharan dust and biomass burning, before their potential contamination with local particles. This study is conceived as a preliminary characterization on the atmosphere over Natal based on meteorological features including air mass clustering. On one hand, this work will allow to identify periods with the largest frequency of Saharan dust outbreaks and biomass burning episodes over Natal. On the other hand, it will provide a statistically detailed characterization of meteorological conditions in this region. To this aim, GDAS information (Global Data Assimilation System) will be the inputs in our analyses and HYSPLIT model (Hybrid Single Particle Lagrangian Integrated Trajectory model) (version 4.9) will be used to generate daily backward trajectories at six standardized height levels.

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  • IPEN-DOC 27019

    MOREIRA, GREGORI de A. . Intercomparison of wind data observed with Wind Doppler LIDAR and SODAR at Ressacada, Florianópolis-Brazil. In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: Nowadays, remote sensing equipment has long been used for various studies related to atmosphere. When wind speed issues are discussed, the Wind Doppler LIDAR and SODAR deserve to be highlighted due to high vertical resolution of both and the high data acquisition rate. This equipment has been very applied in academic studies for environmental issues and also in the industry as wind power projects and airport security. Though each has its limitation, they enable different types of studies, which range from the observation of the vertical wind profile until the detection of turbulent phenomena. The main objective of this work is to do an intecomparison between these two technologies. For this study one measurement campaign was conducted in Florianópolis (Santa Catarina State - Brazi) and a case study will be presented, where were employed a Wind Doppler LIDAR WL70 Leosphere operating with wavelength of 1.5 m and maximum range of 1,500 meters and a SODAR MFAS SCINTEC with maximum range of 800 meters. It will be held: a statistical analysis in relation to the wind velocity and wind direction values, analysis of the turbulence and detection of PBL (planetary boundary layer) height. Both devices will be validated by atmospheric sounding data from the airport near the study area. From the results of this work are expected to find consistent values of correlation between the two devices and demonstrate its wide applicability, although each one have your different limitations, in the various areas of knowledge.

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  • IPEN-DOC 27018

    LANDULFO, EDUARDO ; LOPES, FABIO da S. ; QUEL, EDUARDO; RISTORI, PABLO; BASTIDAS, ALVARO; NISPERUZA, DANIEL; BARBOSA, HENRIQUE; BARJA, BORIS; GOUVEIA, DIEGO A.; FORNO, RICARDO; MONTILLA, ELENA. LALINET a.k.a. Activities. In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: The LALINET network activities will be given focusing on the lidar station characterization in the network, the efforts given to standardize the algorithms as weel the main scietific drives for data collection.

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  • IPEN-DOC 27017

    LOPES, FABIO J.S. ; ARRUDA, GREGORI M. de ; ARAUJO, FELIPE V. ; LANDULFO, EDUARDO . Synergy between multichannel Raman Lidar system and spaceborne remote sensing platforms applied to study aerosol optical properties at Metropolitan Area of São Paulo - Brazil. In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: In the last decades, several remote sensing platforms, i.e., spaceborne, aircraft and ground-based measurement systems have been developed or improved to conduct studies of aerosol and cloud optical properties on local and global scales, as well as to provide the scientific basis for understanding the Earth climate system. The combination measurements between spaceborne sensors and ground-based instruments can helps to provide a better understanding about the impact of aerosols on air quality and in the climate changes inside large cities. The Metropolitan Area of São Paulo (MASP), one of the largest megacities in the world, frequently suffers with problems related to the air quality. Concerned with the pollution scenario of MASP, several measurement campaigns were conducted since 2012, specially, during the South hemisphere winter, period when the low temperatures and the low level of precipitation contribute to the poor dispersion of aerosols. A multichannel Raman Lidar system and air quality monitoring stations from University of São Paulo and Environment Agency of São Paulo State (CETESB) were employed in order to monitor the increasing of aerosol load in the atmosphere. Satellite data from CALIPSO and AQUA were applied to draws the pollution scenario and the most frequent aerosol type at MASP. This study intend to present how the synergy between ground-based monitoring and satellite data can helps to improve the studies the effects of particulate matter concentration in the air quality of MASP and the influence of aerosol from biomass burning advected from large range distance of South American continent.

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  • IPEN-DOC 27016

    BARBOSA, HENRIQUE de M.J.; BARJA, BORIS; GOUVEIA, DIEGO A.; LANDULFO, EDUARDO ; ALMEIDA, PAULO ; HOLANDA, BRUNA A.; PAULIQUEVIS, THEOTONIO; ARTAXO, PAULO; MARTIN, SCOT. Disentangling the Manaus pollution plume from the biomass burning plume during the second GoAmazon 2014/5 Intensive Operating Period (IOP2). In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: The Green Ocean Amazon experiment (GoAmazon2014/5) seeks to understand how aerosol and cloud life cycles are influenced by pollutant outflow from a large industrial city in the tropical rain forest, particularly the susceptibility to cloud-aerosol-precipitation interactions and the feedbacks among biosphere and atmosphere functioning and human activities. For this purpose, six research sites were setup at different distances upwind and downwind from Manaus, in the central Amazon forest, and three of these have vertical profiling capabilities. A micropulsed lidar (MPLnet) from DOE/ARM is being operated at T3 site (3.21°S 60.59°W), 60 km downwind to the west of Manaus. A portable Raymetrics aerosol raman lidar from IPEN/SP was operated T2 site (3.21 ºS 60.60 ºW, 5 km downwind) during the second Intensive Operating Period (IOP2), and measures directly the emissions from Manaus. The third system is the UV Raman lidar from the University of Sao Paulo, continuously operated since 2011 at T0e (2.89 ºS 59.97 ºW), an upwind site 10 km to the east. T0e serves as a reference station, as the air masses there are not influenced by the local urban emissions. Using these three lidar systems and the AERONET stations at T3 and T0e, the scattering and absorption properties of the Manaus and biomass burning plumes were investigated. The measurements were conducted during the biomass-burning season, from August 15 to October 15 2014. Scattering aerosol optical thickness varied from 0.1 to 1.5, with a regression coefficient of 0.980.02, showing similar scattering properties at T0e vis-à-vis T3 and thus little influence of the Manaus plume. For the absorption AOD, however, values ranged from 0.05 to 0.8 and the regression coefficient was 2.2(2), indicating a much more absorbing aerosol at T3. A similar result was observed in the vertical. The aerosol backscatter profiles from T2 and T0e were remarkably similar, and even small-scale vertical structures of about ~100m inside the biomass burning plume were not destroyed as the air mass travels 36 km over the city and the river. The night-time aerosol extinction profiles, however, showed substantially more absorption at T2 then at T0e although not enough to justify the different absorption AOD. Possible reasons will be explored and discussed.

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  • IPEN-DOC 27015

    LANDULFO, EDUARDO ; LOPES, FABIO J.S. ; MOREIRA, GREGORI A. ; GUERRERO-RASCADO, JUAN L.; ALADOS-ARBOLEDAS, LUCAS; HOELZEMANN, JUDITH J.; FERNANDEZ, JOSE H.; LEME, NEUSA P.. Observation and characterization of the transcontinental aerosol transportation from Africa to South America continent: introducing a new Lidar system to LALINET. In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: Saharan mineral dust can affect the environment and climatic processes from the Western Africa, Europe and the Eastern region of Americas due the large carrying processes of dust aerosol. This type of aerosol can interact with the incoming energy from the Sun and alter radiation budget of the Earth-atmosphere system. Dust particles can also change the cloud lifetime and albedo; they can induce precipitation and indirectly influence the convective clouds height. Several studies have been conducted to understanding the physical and optical properties of dust particles, using systems onboard satellites, airborne or ground-based instruments. However, most of the studies were focused on African, European or North America regions. In order to fill the scientific knowledge gap in the South America region it has been developed a new lidar system to study the transcontinental transportation of dust aerosols from Sahara region to South America. The project has as objectives monitoring the dust aerosols transportation seasonality, their vertical distributions in the atmosphere, their physical and optical properties and their influences on the radiative budget. For this task, a four-channel ground based lidar for aerosol profiling, including polarization, is being deployed at the city of Natal, in the North-Northeast region of Brazil. In this study, we present a review of the project current instrumental status, instrument technical specification, the potential results to be obtained and the entire performance test to be done in order to introduce the new lidar system into Latin American Network LALINET according to procedures developed by Guerrero-Rascado et al 2014.

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  • IPEN-DOC 27014

    CORDOBA-JABONERO, CARMEN; LOPES, FABIO J.S. ; LANDULFO, EDUARDO ; CUEVAS, EMILIO; OCHOA, HECTOR; GIL-OJEDA, MANUEL. Subtropical and polar Cirrus clouds characterized by ground-based lidars and CALIPSO/CALIOP observations. In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: Cirrus clouds are product of weather processes, and then their occurrence and macrophysical/optical properties can vary significantly over different regions of the world. Since Cirrus clouds usually are located from 7 km height up to tropopause altitudes, active remote sensing techniques, mainly lidar systems, are usually used for detection of Cirrus clouds from ground-based and space observations. Lidars can provide height-resolved measurements with a relatively good both vertical and temporal resolutions, making them the most suitable instrumentation for high-cloud observations. The aim of this work is to show the potential of lidar observations on Cirrus clouds detection in combination with a recently proposed methodology to retrieve the Cirrus clouds macrophysical and optical features. In this sense, a few case studies of cirrus clouds observed at both subtropical and polar latitudes are examined and compared to CALIPSO/CALIOP observations. Lidar measurements are carried out in three stations: Sao Paulo (Brazil, 23.6°S/46.8°W) and Sta. Cruz de Tenerife (Spain, 28.5°N/16.3°W), being both subtropical sites, and the Belgrano II base (Argentina, 78ºS/35ºW) in the Antarctic continent. Local radiosounding profiles are also used for cirrus-temperature correlation analysis. Optical (COD-cloud optical depth and LR-Lidar Ratio) and macrophysical (top/base heights and thickness) properties of both the subtropical and polar cirrus clouds are reported. This study is focused on the classification of the daily cloud features into three Cirrus COD-related categories: svCi-subvisual (COD < 0.03), stCi-semitransparent (COD: 0.03 - 0.3), and opCi-opaque (COD > 0.3) clouds. In general, subtropical Cirrus clouds present lower LR values and are found at higher altitudes than those detected at polar latitudes. Additionally, a higher svCi presence is observed over the polar station along the day, since svCi clouds are formed at lower temperatures. A good correlation agreement is also achieved between groundbased lidars and space-borne CALIOP measurements.

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  • IPEN-DOC 27013

    GONZALEZ, BORIS B.; BARBOSA, HENRIQUE; GOUVEIA, DIEGO A.; LANDULFO, EDUARDO ; ALMEIDA, PAULO . Characteristics of cirrus clouds in the Central Amazon region during the Intensive Observational Period in the dry season 2014 as part of the GOAMAZON experiment. In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: Using three lidar systems around the city of Manaus, the behavior of the cirrus clouds in the region was investigated. The measurements were conducted during the second GoAmazon 2014/5 Intensive Operating Period (IOP2), from August 15 to October 15, in the dry season of 2014. The three systems were operated continuously at the sites T3, downwind and 60 km to the west of Manaus; T2 (3.21 ºS 60.60 ºW), also downwind of Manaus but just across the Negro river to the west; and T0e (2.89 ºS 59.97 ºW), an upwind site east of Manaus located in campus of Embrapa. These different sites were selected for GoAmazon 2014/5 to measure the effects on aerosols and clouds of different levels anthropogenic pollution, in an otherwise pristine tropical rainforest environment. From the analysis of individual 5-min backscatter profiles, we investigate the statistical distribution of cirrus clouds base and top altitude characteristics; and also the cloud optical depth for the three sites. Mean characteristics for the cirrus clouds measured in the three sites are discussed and the relations between these results are investigated. The cirrus clouds are frequent cloud in the three sites during the dry season. Comparisons with cloud optical depth from sun-photometer in T0e and T3 sites and base height from ceilometer in T3 site were conducted.

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  • IPEN-DOC 27012

    GUERRERO-RASCADO, J.L. ; COSTA, R.F. da ; BEDOYA, A.E.; GUARDANI, R.; ALADOS-ARBOLEDAS, L.; BASTIDAS, A.E.; LANDULFO, E. . Recent advances in the Cubatão scanning lidar to monitor industrial flares. In: WORKSHOP ON LIDAR MEASUREMENTS IN LATIN AMERICA, 8th, April 6-10, 2015, Cayo Coco, Cuba. Abstract... 2015.

    Abstract: This study present the recent advances made on a multiwavelength elastic scanning lidar placed at the industrial area of Cubatão in the State of São Paulo (Brazil). Special attention has been paid to the characterization of the instrumental performance of this lidar system, in particular regarding to its electronic subsystem. To this aim, the quality assurance tests, regularly applied in well-established lidar networks such as LALINET and EARLINET, were applied to the Cubatão scanning lidar in order to improve the knowledge of its performing itself and to design protocols for correcting lidar signal for undesirable instrumental effects. In particular, the trigger delay was assessed by means of zero-bin and bin-shift tests for analog and photo-counting signals, respectively. Dark current test is also performed to detect potential range-dependency that could affect lidar products. The application of the results derived from these tests together with the state-of-the-art methodologies to characterize the particle optical and microphysical properties inside industrial flares demonstrate the potential of this lidar for the study and measurement of industrial emissions.

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  • IPEN-DOC 27009

    SANTOS, I.P. ; LEVY, D.S. . Produção de energia elétrica a partir de fontes nucleares: uma abordagem para estudantes do ensino médio. In: SIMPOSIO INTERNACIONAL SOBRE EDUCACIÓN, CAPACITACIÓN Y GESTIÓN DEL CONOCIMIENTO EN ENERGÍA NUCLEAR Y SUS APLICACIONES, November 22-26, 2015, Cusco, Peru. Proceedings... 2015.

    Abstract: This study reports a pedagogical experiment in high school classes, in a private school in São Paulo. The purpose of this experiment was to put students in touch with topics related to electric power generation from radioactive sources This project was developed with emphasis on the content available in an educational online portal, the site www.radioatividades.com.br. The site has been created in order to disseminate knowledge to children, adolescents, parents and teachers about the peaceful use of nuclear energy. The portal content is free to access and use for educational purposes. The project had three stages: initial dynamics on the subject with students, working with research groups, conducting short courses in the portal "radioatividades" and a final evaluation, which consisted in seminars prepared by students themselves. The first stage aimed to verify the previous knowledge that students had on nuclear energy, raising common prejudices that usually appear. The second phase of the project aimed to demystify some concepts, such as the insecurity linked to the use of atomic energy. For this research there were used reliable sources, as the site of the National Nuclear Energy Commission (CNEN), Institute of Radiation Protection and Dosimetry (IRD) and International Atomic Energy Agency (IAEA), as well as short courses offered by the portal "Radioatividades". To finish the project, the students formed groups and presented seminars for their classmates, with split topics, illustrative slides and post presentation time to answer questions. There were highly satisfactory results at the end of the project, performances with good theoretical foundation and valuable clarifications on nuclear energy.

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  • IPEN-DOC 27008

    MILANI, CAIO J.; BEVILACQUA, JOYCE da S.; RODRIGUES JUNIOR, ORLANDO . Simulation of the difusion of ferric ions in fricke-gel dosimeters with a variable difusion coefficient. In: WORKSHOP ON MATHEMATICAL METHODS AND MODELING OF BIOPHYSICAL PHENOMENA, March 1-7, 2015, Cabo Frio, RJ. Abstract... Rio de Janeiro, RJ: Instituto de Matemática Pura e Aplicada, 2015.

    Abstract: Dosimetry in three dimensions allows the confirmation and a better understand-ing of a treatment in Radiotherapy. Fricke-Gel dosimeters are tissue equivalentand can be molded in different geometries and volumes. After the irradiation,the assessment of the irradiated volumes can be performed with magnetical res-onance imaging (MRI) or optical-CT. On both cases, the quality of the imagescan be compromised by the mobility of the ferric ions (F e3+), formed during thethe interaction of the radiation with the matter, increasing the uncertainty inthe determination of the isodoses in the volume. In this work, the phenomenonof the diffusion of the ferric ions formed by an irradiated region is simulated ina three-dimensional domain considering a variable diffusion coefficient. This dy-namic is modeled by a partial differential equation and solved numerically by anADI algorithm. Graphical visualizations of the phenomenon are presented forbetter understanding of the process.

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  • IPEN-DOC 27007

    MILANI, CAIO J.; BEVILACQUA, JOYCE da S.; RODRIGUES JUNIOR, ORLANDO . Numerical simulation of the difusion of ferric ions in fricke-gel dosimeters. In: CHILEAN WORKSHOP ON NUMERICAL ANALYSIS OF PARTIAL DIFFERENTIAL EQUATIONS, 50th, January 11-15, 2016, Concepción, Chile. Abstract... Concepción, Chile: Centro de Investigación en Ingeniería Matemática - Universidad de Concepción, 2016.

    Abstract: Radiation Dosimetry is a field concerned in measuring absorbed doses of radia- tion using different techniques. The chemical dosimetry using Fricke-Gel dosimeters allows the confirmation and a better understanding of radiotherapy treatments. This technique involves the assessment of volumes composed by irradiated ferrous sulphate solutions and the dose es- timatives can be evaluated using images from optica-CT or magnetic resonance. In both cases, the time elapsed between the irradiation and the evaluation of doses is an important factor, because the ferric ions formed after the irradiation begin to move along the gel matrix causing imperfections in the obtained estimatives. In this work, the dynamics involving the ferric ions, modelled by Fick's Second Law, is investigated and solved numerically. A suitable numerical method was chosen regarding the theoretical aspects such as convergence, consistency, stabil- ity and computational efficiency to simulate the diffusion of the ferric ions in bidimensional and tridimensional enviroments under several hypothesis such as multiply connected domains and non-constant diffusion coefficients. The approximated solutions were obtained with a pre- fixed precision and graphical respresentations of the phenomenum are presented for a better visualization of the problem.

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  • IPEN-DOC 27006

    GOULART, F. ; ICHIKAWA, R.U. ; TURRILLAS, X.; MARTINEZ, L.G. . Study on the microstructure of UNS S32304 duplex steel submitted to heat-treatments. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 45-48. DOI: 10.5151/phypro-viii-efa-12

    Abstract: Duplex stainless steels are characterized by a good combination of mechanical properties and corrosion resistance. Due to the metastable equilibrium between the ferritic (α) and austenitic (γ) phases, significant changes in the microstructure of these steels may occur when subjected to temperatures higher than the ambient, degrading their properties. In this work, it was investigated the influence of heat treatments on the microstructure and mechanical properties of a duplex stainless steel UNS-S32304. The heat-treatments were performed at four temperatures (300°C, 600°C, 900°C and 1000°C) with two treatment times (1 h and 6 h) and two processes of cooling down (in air and water). The samples were studied by X-ray diffraction using Pawley method to determine the lattice parameters, mean crystallite sizes and microstrain for the two phases and compared to Vickers microhardness results.

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  • IPEN-DOC 27005

    REIS, L.A.M. ; ALENCAR, M. ; GOMES, M.P. ; PEREIRA, L.A.T. ; MUCSI, C.S. ; ROSSI, J.L. . Study of recycling process viability of zirconium alloys chips for melting in VAR furnace. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 65-67. DOI: 10.5151/phypro-viii-efa-16

    Abstract: Cavacos de ligas de zircônio (M5, Zirlo, Zircaloy) são gerados em elevadas quantidades na confecção de tubos e tampões das varetas que compõem o elemento combustível de reatores de potência refrigerados a água pressurizada (PWR). Essas são ligas importadas e por isso é mostrado interesse pela indústria de reciclagem na sua reutilização. Este trabalho apresenta os estudos de um processo de reciclagem e a obtenção de eletrodos prensados para serem fundidos em um forno VAR (Vacuum Arc Remelting). O processo se inicia com uma separação magnética, lavagem do fluido de corte que é solúvel em água, utilização de um desengraxante industrial, seguido por um enxágue com fluxo contínuo de água em alta pressão e secagem por fluxo de ar quente. Para a obtenção de eletrodos, os cavacos foram prensados em uma matriz de seção quadrada 40x40 mm² com 500 mm de comprimento, resultando num eletrodo com 20% da densidade aparente da liga. A fusão foi feita um forno VAR de laboratório no CCTM-IPEN, gerando um lingote maciço de 0,8 kg. A fusão dos cavacos é possível e viável em um forno VAR o que reduz em até 40 vezes o volume de armazenamento desse material.

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  • IPEN-DOC 27004

    ABBADE, L. ; LARA, J.A.C. ; COUTO, C.P. ; GONSALEZ, B. ; COLOSIO, M.A.; ROSSI, J.L. . Resistance spot welding characterization of press hardened steel. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 10-13. DOI: 10.5151/phypro-viii-efa-03

    Abstract: In the automotive industry the resistance spot welding (RSW) is one of the most used processes for joining steel sheets, being of fundamental importance the quality assurance of this process. In this work, 22MnB5 steel sheets for the hot stamping process, also known as PHS (Press Hardening Steel), were joined by the technique of resistance spot welding, so that the welding parameters were changed 16 times for the evaluation of the influence of these parameters on the mechanical properties. By conducting ultrasonic, tensile and hardness test, followed by metallography, it was possible to identify the characteristics of the spot weld effect on the material. The results of the tests performed in this work confirmed the difference in mechanical strength of the thermal zone (ZTA) in relation to the molten zone (ZF). For a certain set of the parameters it was shown a decrease in the strength of the ZTA and increasing to the weld point, which is demonstrated in the microstructural analysis and thus justifies the detachment of the weld button of the base material during tensile testing, i.e., there was a higher strength in the welded area.

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  • IPEN-DOC 27003

    NASCIMENTO, J.O. do; PEREIRA, H.B.B.; MORET, M.A.; BARBOSA, L.P. ; TAKIISHI, H. . Redes semânticas em Ciências dos Materiais: uma aplicação da Teoria de Redes. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 116-121. DOI: 10.5151/phypro-viii-efa-27

    Abstract: Uma possibilidade de estudos em sistemas complexos corresponde a utilização da Teoria de redes sociais e complexas. Este artigo tem como objetivo descrever e analisar as redes semânticas baseadas nas palavras-chave dos artigos publicados nos anais do Congresso Brasileiro de Engenharia e Ciências dos Materiais (CBECiMat) referente ao ano de 2010. Alicerçamo-nos nas métricas de estatística básica pertencente às redes complexas, ao índice de centralidade de grau pertencente as redes sociais e apresentamos o método de construção das redes semânticas. As análises indicaram quais as palavras-chave se destacaram (por meio do número de suas conexões) e as topologias verificadas, sugerem redes livre de escala e mundo pequeno. Estes resultados auxiliam na escolha e observância de palavras-chave em futuros trabalhos nas áreas de ciências dos materiais e do evento (materiais cerâmicos, materiais compósitos, materiais metálicos, materiais poliméricos e ensino de materiais), bem como arguir sobre estratégias em mecanismos de busca de trabalhos científicos, tendo como descritores as palavras-chave.

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  • IPEN-DOC 27002

    GOMES, M.P. ; SANTOS, I.P. ; COUTO, C.P. ; BETINI, E.G. ; COLOSIO, M.A.; ROSSI, J.L. . Microstructural characterization of air quenched valve seat inserts obtained with AISI D2 tool steel. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 42-44. DOI: 10.5151/phypro-viii-efa-11

    Abstract: The obtention of valve seat insert (VSI) by powder metallurgy using a mixture of iron powder and tool steel is fulfilling the requirements for substitution of cobalt and lead in commercial parts, aiming cost reduction and avoid the lead toxicity. The aim of this work consisted of evaluate the influence of heat treatment on VSI obtained with AISI D2 tool steel powder. The AISI D2 tool steel powder was mixed with iron powder and additives such as manganese sulphide, zinc stearate, graphite and carbides. The heat treatment of the VSI consisted of air quenching followed by double tempering it at 500 °C. The microstructural characterization was performed using scanning electron microscopy and energy dispersive spectroscopy.

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  • IPEN-DOC 27001

    GOMES, M.P. ; SANTOS, I.P. ; REIS, L.A.M. ; CIONE, F.C. ; COLOSIO, M.A.; ROSSI, J.L. . Influence of air quenching on apparent hardness of valve seat inserts obtained with AISI M2 high-speed steel powder. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 39-41. DOI: 10.5151/phypro-viii-efa-10

    Abstract: The aim of this work consisted of evaluate the influence of heat treatment on sintered valve seat inserts (VSI) obtained with the AISI M2 high-speed steel powder. The AISI M2 high-speed steel powder was mixed with iron powder and additives such as manganese sulphide, zinc stearate, graphite and carbides. The heat treatment of the VSI consisted of air quenching followed by double tempering it in seven different equidistant temperatures, from 100 °C until 700 °C. The mechanical property was measured regarding the VSI apparent hardness. The results indicated that the VSI obtained with the AISI M2 high-speed steel powders mixtures showed the best results regarding its apparent hardness after air quenching and double tempering it at 600 °C.

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  • IPEN-DOC 27000

    BETINI, E.G. ; GOMES, M.P. ; REIS, L.A. ; MUCSI, C.S. ; ALENCAR, M.C. ; ORLANDO, M.T.D.; LUZ, T.S.; AVETTAND-FENOEL, M-N.; ROSSI, J.L. . Effect of the cooling rates on heat-affected zone of UNS S32304 duplex stainless steel welded by pulsed GTAW process. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 14-18. DOI: 10.5151/phypro-viii-efa-04

    Abstract: Two thin plates of UNS 32304 of duplex stainless steel were joined by pulsed gas tungsten arc welding (GTAW) using a mixture 98% of argon plus 2% of nitrogen as shielding gas or pure argon as purging gas at the bottom of the plate without filler metal. The temperature profile close and away from the weld pool was measured using K type (Ni-Cr) thermocouples, connected to a digital data acquisition system. The thermal cycles was recorded in the heat-affected zone (HAZ) at a distance in between 1 and 3 mm from the joint line. The cooling rate and holding time were studied with respect to the used purging gas. Experimental thermal profiles are in good agreement with literature values. The joints welded without any purging gas revealed high peak temperature and cooling rates. The present investigation showed that temperature peaks are comprised in the phase transformation temperature ranges for the welded duplex stainless steel.

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  • IPEN-DOC 26999

    PASCOATO, R. ; ARANHA, L.C. ; MUCSI, C.S. ; ROSSI, J.L. . Desenvolvimento de um torquimetro para medição dinâmica de microtorque. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 62-64. DOI: 10.5151/phypro-viii-efa-15

    Abstract: Foi desenvolvido um dispositivo protótipo de um torquímetro para ensaio de medição dinâmica de micro torques. Este dispositivo foi usado para a avaliação de implantes ortodônticos. O ensaio consistiu na inserção e retirada de pilares protéticos em implantes odontológicos, com torques menores que 100 Ncm. O principal componente desse protótipo foi a barra de torque, nesta, foi aplicado um extensômetro tipo strain gage. As deformações sofridas por este componente, não descriminavam entre deformações devido a tensões de flexão e tensões de torção. Com o propósito de diminuir esta sensibilidade a deformação por flexão e aumentar a sensibilidade da torção, foi proposta uma nova geometria para a barra de torque. Após ser estudada analiticamente, esta nova geometria mostrou- se bastante favorável quanto ao aumento da sensibilidade à torção do componente e a diminuição da interferência devido ao seu peso próprio.

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  • IPEN-DOC 26998

    SOUZA, A.C.; SILVA, A.C.; ROSSI, J.L. ; CIONE, F.C. . Analysis thermogravimetric of tungsten composite for gama radiaction shielding. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 36-38. DOI: 10.5151/phypro-viii-efa-09

    Abstract: The generation of Mo-99mTc generators for hospitals requires the transport of the Mo-99m material in containers with physicochemical properties for especially the shielding of gamma radiation [4, 5]. The application of tungsten alloys has been developed with the objective of minimizing the effects of radiation, being used in the manufacture of devices for the transport of radioactive material, considering its properties of specific mass (60% dense than lead), resistance corrosion, excellent absorption of high energy radiation and high mechanical strength [16,17]. The kraft lignin, a natural polymer obtained from the Kraft process of cellulosic pulp extraction, considered a residue of the cellulosic industry, can be used as a high adhesive material. The objective of this work was to perform the Thermogravimetric (TG), Differential Exploration Calorimetry (DSC) and X-ray diffraction (XRD) analyses of a new composite of tungsten and kraft lignin. The results showed the thermal and crystallographic properties of the composite, which could contribute to obtain a new material with ability to attenuate gamma radiation.

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  • IPEN-DOC 26997

    SOUZA, A.C.; ROSSI, J.L. ; FERNANDES, H.B.; GOUVEA, A.F.G.. Analysis of the microstructural evolution of composite of Tungsten with lignin kraft. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 76-78. DOI: 10.5151/phypro-viii-efa-19

    Abstract: In materials science and engineering, there is a demand in new materials for radiation shielding in the transport of radiopharmaceuticals used in the diagnosis and therapy of cancer, justifying the interest in developing this work. The obtained lignin kraft and tungsten form the precursors used for metal-organic composite. Tungsten metal has diverse applications in the nuclear sector presents an enormous mechanical strength and an excellent cross section with thermal neutrons. The aim of this study is to analyse the microstructural evolution of metal-organic composite using the kraft lignin and tungsten, using analysis of scanning electron microscopy (SEM), microhardness test and x-ray diffraction (XRD). Microscopic analysis showed the granulometry of the precursors separate and composite morphology, observing the formation of alpha (α) and beta (β) phases and absence of oxidation process for different heat treatment temperatures. The spectra of x-ray diffraction identified the structures of each phase formed and micro hardness measures showed an increase of mechanical resistance with temperature. The results of the microstructural characterization of metal-organic composite, will contribute in the next steps of attenuation measurements of gamma radiation.

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  • IPEN-DOC 26996

    COSTA, P.D.O.L. ; COSTA, I. ; COUTO, C.P. ; ROSSI, J.L. . Análise gravimétrica do revestimento de zinco-níquel de um aço 22MNB5 e zinco puro. In: ENCONTRO CIENTÍFICO DE FÍSICA APLICADA, 8., 4-7 de setembro, 2017, Vitória, ES. Anais... São Paulo, SP: Blucher Proceedings, 2017. p. 29-31. DOI: 10.5151/phypro-viii-efa-07

    Abstract: O aço de alta resistência 22MnB5 é utilizado com revestimento de alumínio-silício com o objetivo de melhorar a resistência a corrosão e desgaste em peças expostas em meios molhados que favorecem o fenômeno corrosivo. Sua principal aplicação é no setor automobilístico englobando peças que integram a estrutura principal do veículo. Uma alternativa para a substituição do revestimento alumínio-silício é uma composição química do revestimento utilizando zinco-níquel. Neste trabalho foi estudado a evolução do processo de perda de massa em diferentes meios corrosivos (ácido, neutro e alcalino) identificando o comportamento do material revestido do aço 22MnB5 e comparando com zinco puro. Foram utilizados três variáveis: revestimento zinco-níquel como recebido, revestimento zinco-níquel estampado e zinco puro. Foi constatado que em meios ácidos (pH de 0 a 1) o processo de corrosão foi muito intenso para todos os materiais, do pH 3 ao pH 13 a perda de massa foi insignificante, mesmo sendo imersa durante dias, havendo a proteção do material pela camada passiva formada de óxido. O revestimento estampado se mostrou com maior tendência a perda de massa, por possuir mais defeitos em sua superfície facilitando o processo corrosivo enquanto que o revestimento como recebido se mostrou bem resistente.

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  • IPEN-DOC 26995

    RAMANATHAN, L.V. ; FERNANDES, S.M.C. ; CORREA, O.V. ; SOUZA, J.A. de ; ANTUNES, R.A.; OLIVEIRA, M.C.L. de. Coatings for safe long term wet storage of spent Al-clad research reactor fuels. In: INTERNATIONAL CONFERENCE ON RESEARCH REACTORS: SAFE MANAGEMENT AND EFFECTIVE UTILIZATION, November 16-20, 2015, Vienna, Austria. Proceedings... Vienna, Austria: International Atomic Energy Agency, 2015. p. 1-8.

    Abstract: Pitting corrosion of the aluminium cladding of spent research reactor (RR) fuels in wet storage has been observed and the use of conversion coatings to protect the cladding was proposed. A coating prepared by conventional chemical processing as opposed to electrochemical processing is the only option due to constraints related to the shape of the fuel and its high radioactivity. Hence, hydrotalcite (HTC) and boehmite were considered. This paper presents: (a) preparation of hydrotalcite (HTC) coatings from different baths followed by post-coating treatments; (b) corrosion behavior of HTC coated AA 6061 alloy; (c) results of field studies in which uncoated and HTC coated AA 6061 alloy coupons and plates, the latter assembled as a dummy fuel element, were exposed to the IEA-R1 reactor spent fuel basin for extended periods. The laboratory and field tests revealed marked improvements in the corrosion resistance of HTC coated specimens, coupons and plates. The mechanism of corrosion protection is presented.

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  • IPEN-DOC 26994

    GOMES, M.P.; SANTANA, M.S.; ROSSI, J.L. ; POLITANO, R. . Estudo da energia mecânica necessária para a geração de pulsos mecânicos em uma barra de Kolsky. In: CONGRESSO CIENTÍFICO DA SEMANA NACIONAL DE CIÊNCIA E TECNOLOGIA NO IFSP, 6., 20-23 de outubro, 2015, Bragança Paulista, SP. Anais... Bragança Paulista, SP: Instituto Federal de São Paulo - Bragança Paulista, 2015.

    Abstract: A análise da resposta a pulsos mecânicos em materiais a serem utilizados em sistemas para transporte de substâncias radioativas é uma das condições para a sua respectiva seleção e dimensionamento. Para que se faça a caracterização da resposta dos materiais candidatos a este tipo de solicitação é necessária a construção de aparatos experimentais, sendo que neles é aplicado um pulso mecânico de forma controlada e com parâmetros conhecidos, possibilitando assim a obtenção das características mecânicas do corpo-de-provas - aparato este conhecido como barra de Kolsky. Uma parte crítica do aparato, é o alinhamento de todo o conjunto, pois o ensaio a ser realizado é considerado unidimensional. O menor desalinhamento irá causar distorções na onda mecânica de compressão, então os dados obtidos pela extensometria na superfície das barras não serão condizentes com a realidade. Portanto, o propósito deste projeto foi o de produzir um mancal que possibilitasse o alinhamento com uma maior precisão dos eixos x, y do aparato. Tal alinhamento será inicialmente feito manualmente, porém no dimensionamento e concepção do mancal foi reservado um espaço para o acoplamento de um servomotor, que futuramente irá ser utilizado para o ajuste preciso e automático do aparato.

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  • IPEN-DOC 26993

    HELENO, S.A.; VILLAVICENCIO, A.L.C.H. ; BARROS, L.; FERREIRA, I.C.F.R.. A influência da radiação gama na composição nutricional de flores comestíveis de Bauhinia variegata L. provenientes do Brasil. In: BENTO, ALBINO A. (Ed.) CONGRESSO NACIONAL DAS ESCOLAS SUPERIORES AGRÁRIAS, 1., 2-3 de dezembro, 2015, Bragança, Portugal. Resumo... Bragança, Portugal: Instituto Politécnico de Bragança, Escola Superior Agrária, 2015. p. 249-249.

    Abstract: Desde há muitos anos que a utilização de flores comestíveis na culinária se tornou uma prática comum, uma vez que conferem uma melhor qualidade sensorial e nutricional aos alimentos, para além do aspeto visual atrativo [1,2]. Bauhinia variegata L. é uma árvore muito comum no Brasil, sendo as suas flores grandes e de coloração lilás na variedade mais comum. Estas flores são vulgarmente conhecidas como “pata de vaca”, sendo comestíveis e muito utilizadas em saladas e na decoração de vários pratos nas cozinhas Gourmet. No presente estudo, as flores foram submetidas a radiação por feixe de eletrões em diferentes doses (0.5 e 0.8 KGy) para efeitos de descontaminação, e seguidamente analisadas em termos de parâmetros nutricionais nomeadamente, composição centesimal (humidade, proteínas, gordura, hidratos de carbono e cinzas), perfil em açúcares livres (determinados por HPLC-RI) e em ácidos gordos (analisados por GC-FID). As amostras não irradiadas (controlo) e irradiadas revelaram um perfil nutricional muito similar, sendo que os hidratos de carbono foram os nutrientes mais abundantes, seguidos das proteínas, cinzas e gorduras. Relativamente aos açúcares, as amostram mostraram também um perfil semelhante, tendo sido identificados: a frutose em maior quantidade, seguida da glucose e da sacarose. Os ácidos gordos: palmítico (C16:0), esteárico (C18:0), oleico (C18:1n9), linoleico (C18:2n6) e α-linolénico (C18:3n3) foram os mais abundantes nas amostras em estudo, tendo sido identificados mais 16 ácidos menos abundantes. Os ácidos polinsaturados (PUFA) foram maioritários, seguidos dos saturados (SFA) e monoinsaturados (MUFA). Também neste caso as amostras revelaram uma composição muito idêntica. Em suma, a técnica de irradiação pode ser utilizada como forma de descontaminação e preservação de flores comestíveis uma vez que as doses aplicadas não alteraram significativamente os parâmetros nutricionais das amostras em estudo.

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  • IPEN-DOC 26992

    FERREIRA, ALLANA C.P.; SANTOS, ELINALDO N. dos; MESQUITA, ARIMATEA P. de P.; ARAUJO, EDVAL G. de; GONZALEZ, CEZAR H.; AMBROZIO FILHO, FRANCISCO ; ARAUJO FILHO, OSCAR O. de. Endurecimento secundário do aço rápido AISI M3:2 nome comercial Sinter 23 produzido por uma técnica de metalurgia do pó / Secondary hardening of an AISI M3:2 high speed steel named Sinter 23 produced through powder metallurgy techniques. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 70.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALÚRGICA, DE MATERIAIS E DE MINAS,15., 17-21 de agosto, 2015, Rio de Janeiro, RJ. Proceedings... São Paulo, SP: Blucher Proceedings, 2015. p. 1755-1762.

    Abstract: O endurecimento secundário de aço rápido AISI M3:2 nome comercial Sinter 23 obtido por uma técnica de metalurgia do pó de sinterização por compactação isostática a quente é objeto desse trabalho de pesquisa. O aço rápido em questão foi austenitizado em banho de sal a 1.140°C, 1.160°C, 1.180°C e 1.200C, temperado ao ar e revenimento a 540°C, 560°C e 580C. Amostras do aço rápido foram fabricadas e submetidas ao tratamento térmico acima descrito e submetida a ensaios de dureza Vickers e Rockwell C para a determinação das suas respostas ao tratamento térmico de endurecimento e avaliação do pico de endurecimento secundário através dos resultados de dureza.

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  • IPEN-DOC 26991

    DEL BUSSO, NICOLANGELO; MONTEIRO, WALDEMAR A. . Caracterização microestrutural e mecânica de aço API-5L-X70 após soldagem pelo método de arco submerso / Mechanical and microstructural characterization in API 5L X70 steel after submerged arc welding process. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 70.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALÚRGICA, DE MATERIAIS E DE MINAS,15., 17-21 de agosto, 2015, Rio de Janeiro, RJ. Proceedings... São Paulo, SP: Blucher Proceedings, 2015. p. 1665-1674.

    Abstract: A soldagem é um processo industrial empregado na indústria do petróleo e em minerodutos devido ao sua excelente resistência mecânica. Os seus parâmetros provocam alterações metalúrgicas significativas no metal de solda. Neste trabalho foi estudado o aço microligado da classe API-5L-X70 em termos de microestrutura (metalografia e fratografia por microscopia óptica e eletrônica) e propriedades mecânicas (ensaio de tração a temperatura ambiente, dureza, dobramento e ensaio de impacto Charpy a – 20o C e a 0o C) após soldagem em arco submerso, nas regiões da zona fundida (ZF), zona termicamente afetada (ZTA) e metal de base (MB). O exame metalográfico apresentou microestrutura bandeada consistindo de ferrita poligonal, perlita e bainita, com pequeno tamanho de grão. Os resultados mostram o aumento da resistência mecânica influenciada pela presença de ferrita acicular. Análise fratografica apos ensaios mecânicos revelam comportamento dúctilfrágil.

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  • IPEN-DOC 26990

    HELENO, SANDRINA A.; VILLAVICENCIO, ANNA L.C.H. ; BARROS, LILLIAN; FERREIRA, ISABEL C.F.R.. Efeitos da radiação por feixe de eletrões no valor nutricional de Bauhinia variegata var cândida: flores comestíveis provenientes do Brasil. In: SIMPÓSIO NACIONAL PROMOÇÃO DE UMA ALIMENTAÇÃO SAUDÁVEL E SEGURA, 2., 26 de novembro, 2015, Lisboa, Portugal. Abstract... Lisboa, Portugal: Instituto Nacional de Saúde Doutor Ricardo Jorge, 2015. p. 64-64.

    Abstract: As flores comestíveis têm sido muito utilizadas nas artes culinárias, sendo uma tradição em todo o munto desde há muitos anos. São utilizadas várias formas, cores e sabores de flores comestfveis, com o objetivo de melhorar a qualidade sensória! e nutricional dos alimentos [1,2]. As flores de Bauhinia variegata L. são grandes e apresentam coloração rosa a lilás na variedade mais comum, ocorrendo ainda uma variedade de flores brancas, denominada B. variegata var Cândida. Estas flores são vulgarmente conhecidas como "pata de vaca branca", sendo comestíveis e muito utilizadas em saladas. No presente estudo, as flores foram submetidas a radiação por feixe de eletrões em diferentes doses (0.5 e 0.8 KGy) como forma de descontaminação, e analisadas em termos de parâmetros nutricionais nomeadamente, composição centesimal (humidade, proteínas, gordura, hidratos de carbono e cinzas) e perfil em açúcares livres (determinados por HPLC-RI) e em ácidos gordos (analisados por GC-FID). As amostras controlo (não irradiadas) e irradiadas apresentaram um perfil muito semelhante; os hidratos de carbono foram os nutrientes mais abundantes nas amostras, seguidos das proteínas, gorduras e cinzas. Os perfis em açúcares foram também similares, estando presentes a frutose em maior quantidade, seguida da gtucose e da sacarose. Os ácidos capróico (C6:0), caprílico (C8:0), cáprico (C10:0), láurico (C12:0), mirístico (C14:0), palmítico (C16:0), esteárico (C18:0) e oleico (C18:1n9) foram os ácidos gordos mais abundantes nas amostras em estudo. Os ácidos gordos saturados (SFA) foram majoritários, seguidos dos mono (MUFA) e potinsaturados (PUFA). No entanto, com maior dose de radiação a percentagem de SFA e MUFA diminui ligeiramente (principalmente ácidos esteárico e oleico, respetivamente), aumentando a percentagem de PUFA (principalmente pelo aumento dos ácidos linoleico e a-linolénico). Em suma, as doses de irradiação aplicadas não alteraram significativamente o valor nutricional das amostras em estudo, podendo ser considerada como técnica de descontaminação e preservação de flores comestíveis.

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  • IPEN-DOC 26989

    SANTOS, A.S.; BITTENCOURT, C.. Gas mitigation in paper production. IOP Conference Series: Earth and Environmental Science, v. 78, p. 1-8, 2017. DOI: 10.1088/1755-1315/78/1/012009

    Abstract: The Brazilian paper industry has competitive advantages offered by the favorable climate, which favors an increase in the yield of forest restoration, and consequently, in the productive process. On the other hand, following the greenhouse gases (GHG), we can see our constantly changing sun, causing the solar storms, allowing their prevention or mitigating measures. The objective of this work is to contribute to the construction of the understanding necessary for the reduction of GHG emission from a preliminary analysis of the pulp and paper sector. As a secondary objective, the text preliminarily analyzes a company's behavior against the backdrop of the Paris Accord, which strengthens the global response to the threat of climate change and strengthens the capacity of countries to deal with the impacts of such changes. The identification of best practices in the pulp and paper industry is understood, focusing on environmental sustainability, such as the adoption of reforestation, obtaining significant results. In the case of the paper industry, the management of public forests for sustainable production, within the structure of the Ministry of the Environment, establishes the promotion of public awareness about the importance of conservation, recovery and sustainable management of forest resources.

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  • IPEN-DOC 26988

    GUERRERO-RASCADO, J.L.; ALADOS-ARBOLEDAS, L.; BENAVENT-OLTRA, J.A.; CAZORLA, A.; CHAMIZO, S.; FOYO, I.; GRANADOS-MUNOZ, M.J.; KOWALSKI, A.S.; OLMO, F.J.; PEREZ-RAMIREZ, D.; SERRANO-ORTIZ, P.; TITOS, G.; CASQUERO-VERA, J.A.; ORTIZ-AMEZCUA, P.; COSTA, M.J.; LOPES, F.J.S. ; LYAMANI, H.; PEREZ-PRIEGO, O.; PREISSLER, J.; MARTIN-TRIGO, O.. E-learning in the teaching-learning process at postgraduate level: application to geomet subjects. In: GOMEZ CHOVA, L. (Ed.); LOPEZ MARTINEZ, A. (Ed.); CANDEL TORRES, I. (Ed.) INTERNATIONAL CONFERENCE ON EDUCATION AND NEW LEARNING TECHNOLOGIES, 9th, July 3-5, 2017, Barcelona, Spain. Proceedings... Valencia, Spain: IATED Academy, 2017. p. 2699-2704. DOI: 10.21125/edulearn.2017.1561

    Abstract: This teaching innovation project arises from experience previously gained with other innovation projects encompassing several degrees with the aim of improving the academic performance of the students and the quality of teaching in several subjects of the Master’s program in Geophysics and Meteorology (GEOMET) at the University of Granada (Spain). Among other novelties, through this project resources have been developed for students to carry out an online self-assessment of their knowledge regarding contents of the different subjects through the Moodle platform, checking the level of skills acquired. In addition, the project includes a system of exchange of teaching, electronic resources between teachers and students (guides of subjects, viewgraphs, practical documents, among others). This platform has increased the coordination between the lecturers who teach the subjects.

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  • IPEN-DOC 26987

    MOREIRA, TATIANA M. ; SEO, EMILIA S.M. . Caracterização e utilização das fibras da casca da laranja como biossorvente na recuperação de corpos hídricos contaminados por derramamento de derivados do petróleo. In: CONGRESSO DA ASSOCIAÇÃO BRASILEIRA DE ENGENHARIA SANITÁRIA E AMBIENTAL; FEIRA NACIONAL DE SANEAMENTO E MEIO AMBIENTE, 2-6 de outubro, 2017, São Paulo, SP. Proceedings... Rio de Janeiro, RJ: Associação Brasileira de Engenharia Sanitária e Ambiental, 2017. p. 1-10.

    Abstract: Com base no desenvolvimento sustentável, este trabalho, visou buscar materiais tecnológicos com enfoque na reciclagem, onde se destacam as fibras vegetais, como as da laranja, que possuem baixo custo e impacto ao meio ambiente, com boa eficiência quando utilizadas para o processo de biossorção. Este método vem sendo utilizado como um recurso para redução de problemas ambientais causados por contaminação em corpos hídricos, como córregos e rios urbanos, por derramamento de substâncias tóxicas, minimizando assim os impactos dos ecossistemas aquáticos, bem como a contaminação do solo. A preparação destas fibras foi feita por meio de tratamentos físicos e químicos, tais como: lavagem, secagem, moagem, mercerização (tratamento químico com agente alcalino que ataca a superfície da fibra, melhorando suas características de sorção), classificação granulométrica e caracterização. Esses procedimentos geraram um material que pôde ser empregado como um biossorvente. Como contaminantes, foram utilizados derivados do petróleo, tais como a gasolina e o óleo diesel. Na caracterização foram utilizadas técnicas de: Picnometria, Termogravimetria, Análise Elementar, Microscopia Eletrônica, Fluorescência de Raios X, Teor de Umidade e Cinzas, Retenção de água, Hidrofobicidade e Flutuabilidade. Para os ensaios práticos foram mensuradas a sorção de contaminantes tanto em sistema seco, onde os contaminantes estão em contato direto com os biossorventes, quanto aquoso, simulando um derramamento de óleo diesel e gasolina em um corpo hídrico. Os resultados demonstraram que o biossorvente testado possui boa capacidade sortiva nos dois sistemas testados. Portanto, dada a sua origem renovável e de baixo custo, este material se mostrou eficiente para a finalidade proposta.

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  • IPEN-DOC 26986

    MILAGRE, MARIANA X. ; MACHADO, CARULINE S.C. ; ARAUJO, JOAO V. ; ASTARITA, ANTONELLO; PEBERE, NADINE; VIVIER, VINCENT; COSTA, ISOLDA . Intergranular corrosion susceptibility of Al-Cu-Li alloys. In: EUROPEAN CORROSION CONGRESS; INTERNATIONAL CORROSION CONGRESS, 20th; PROCESS SAFETY CONGRESS, September 3-7, 2017, Prague, Czech Republic. Proceedings... Frankfurt, Germany: European Federation of Corrosion, 2017.

    Abstract: In the present study, the intergranular corrosion (IGC) susceptibility of commercial Al-Cu-Li alloys of the third generation (AA2098-T351, AA2198-T3 and AA2198-T851) was compared with that of the AA2024-T3 alloy according to ASTM G110 test. In addition, anodic and cathodic polarization curves were carried out in the ASTM G110 test solution at room temperature. The cross-section of the samples after the ASTM G110 test was observed by scanning electron microscopy (SEM) to evaluate the extension of the corrosion attack. The susceptibility to intergranular attack of the tested alloys was ranked according to the attack by IGC and from the anodic and cathodic polarization curves. The results showed that the AA2024-T3 and the AA2198-T3 alloys presented higher susceptibility to intergranular corrosion comparatively to the other alloys tested (AA2098-T351 and AA2198-T851). The AA2098-T351 alloy was associated to the highest resistance to intergranular attack among the alloys evaluated. A correlation was seemingly established between the stress relief treatment of the alloy and its corresponding susceptibility to intergranular or intragranular corrosion.

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  • IPEN-DOC 26985

    COUTO, CAMILA P. ; COSTA, ISOLDA ; COLOSIO, MARCO; GOMES, MAURILIO ; ROSSI, JESUALDO ; BOLSANELLO, MARILIA . Influence of heat treatment on corrosion resistance of press hardened steel coated with AlSi and ZnNi. In: EUROPEAN CORROSION CONGRESS; INTERNATIONAL CORROSION CONGRESS, 20th; PROCESS SAFETY CONGRESS, September 3-7, 2017, Prague, Czech Republic. Abstract... Frankfurt, Germany: European Federation of Corrosion, 2017.

    Abstract: The ultrahigh strength boron manganese steels, also known as PHS (press hardened steels), are strategic materials for the automotive industry, satisfying safety needs and fuel reduction requirements by means of the lightweight design concept, a current trend for new vehicles. It is possible by the hot stamping process which consists in heating a steel blank to the austenitization temperature, transferring it to press tooling, forming and quenching to fully martensitic transformation. At the end of process, the steel achieves tensile strength up to 1,500 MPa. The transference step from furnace to press is a critical stage because it might promote deleterious steel oxidation. The use of metallic coatings avoids this outcome. AlSi coatings have been the most applied on PHS. Alternative coatings such as electroplated ZnNi are under investigation to evaluate their potential for replacement of AlSi coatings, besides to keep up with the high projected world demand. Zinc based coatings are advantageous comparatively to AlSi ones because they provide cathodic protection to steel substrates. In this study the influence of hot stamping heat treatment on corrosion resistance of 25MnB5 steel coated by AlSi and electroplated ZnNi has been investigated. The tests include open circuit potential measurement, electrochemical impedance spectroscopy and anodic polarization curves. The samples have been tested as received and after the heat treatment which consists in heating the sample at 900°C by 10 minutes and then, fast cooling in water. It is expect that the heat treatment changes the corrosion resistance due to the intermetallics formation at the coating layer as a consequence of diffusion.

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  • IPEN-DOC 26984

    ABREU, C.P. ; MELO, H.G. de; PEBERE, N.; MOGILI, N.V.V.; COSTA, I. ; VIVIER, V.. Corrosion resistance evaluation of the different zones on the AA2024-T3 and AA7475-T651 alloys welded by FSW. In: EUROPEAN CORROSION CONGRESS; INTERNATIONAL CORROSION CONGRESS, 20th; PROCESS SAFETY CONGRESS, September 3-7, 2017, Prague, Czech Republic. Proceedings... Frankfurt, Germany: European Federation of Corrosion, 2017. p. 1-14.

    Abstract: The aeronautic industry has a great interest in joining dissimilar aluminium alloys used in different parts of an aircraft. The Friction Stir Welding (FSW) process has been considered an effective alternative to conventional techniques for the welding of high strength alumin-ium alloys. However, this procedure results in zones with different microstructures due to thermal and thermomechanical effects involved during the joining process, leading to the formation of the thermomechanically affected zone (TMAZ), the heat affected zone (HAZ), the stir zone (nugget), and the unaffected base metal (BM). As the corrosion resistance of materials depends on their microstructures, the aim of this study was to investigate the intrin-sic corrosion resistance of the different zones of the AA2024-T3 and AA7475-T761 alloys welded by FSW, without considering the coupling effects between the different zones. This was achieved by evaluating the corrosion resistance of each individual zone in 0.1 M Na2SO4 + 1 mM NaCl solution by electrochemical techniques, such as open circuit potential meas-urements, polarization curves, and electrochemical impedance spectroscopy, using an elec-trochemical cell with an exposed area of 0.78 mm2. The electrochemical results showed that the lowest corrosion resistance was associated to the nugget zone, on which a galvanic cou-pling between the 2024 and 7475 alloys takes place. The corrosion resistance was also low-ered on the TMAZ of both alloys. This behaviour was associated to the enhanced precipita-tion of the η phase (MgZn2) at the grain boundaries in the 7475 alloy and to the coarsening of S phase (AlCuMg) precipitates in the 2024 alloy, both processes favoured by the thermome-chanical effects in these specific zones as demonstrated by TEM analysis.

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  • IPEN-DOC 26983

    SILVA, CAMILA R. ; RIBEIRO, MARTHA S. . Efeitos da terapia com laser em baixa intensidade em melanoma murino: estudo in vivo. In: CONGRESSO BRASILEIRO DE FÍSICA MÉDICA, 22., 6-9 de setembro, 2017, Ribeirão Preto, SP. Resumo expandido... São Paulo, SP: Associação Brasileira de Física Médica, 2017.

    Abstract: Introdução: A terapia com laser em baixa intensidade (TLBI) vem sendo utilizada em uma variedade de condições patológicas e tem ganhado destaque nas áreas da Saúde por ser uma alternativa terapêutica não invasiva. Entretanto, o seu uso em pacientes oncológicos ainda é controverso, já que a literatura mostra resultados conflitantes da TLBI em células tumorais. Assim, nosso objetivo neste trabalho foi investigar os efeitos da TLBI na progressão de melanoma induzido em camundongos. Métodos: Células de melanoma da linhagem B16F10 foram cultivadas em meio RPMI 1640 com 10 % de soro fetal bovino e 1 % de solução antibiótico-antimicótica e incubadas em estufa a 37 ºC com 5% de CO2. Após atingirem a confluência, as células foram contadas em câmera de Neubauer, e separadas na concentração de 1.106 células/mL. Todos os procedimentos foram aprovados pelo Comitê de Ética no Uso de Animais do IPEN-SP. Camundongos machos C57BL/6 (n=8) com aproximadamente 6 semanas de idade e massa corporal de 20 g foram inoculados na região dorsal com 1.106 células/mL de melanoma murino. Após 15 dias, quando os animais apresentaram volume tumoral de 1 cm3, eles foram separados em dois grupos: Controle (n= 4) e Laser (n=4). O grupo Laser foi exposto à TLBI de forma pontual sobre o tumor com um laser de emissão vermelha (λ= 660 nm), potência de 40 mW, energia de 6 J e fluência de 150 J/cm² por três dias consecutivos. O grupo controle foi manipulado da mesma forma, mas não recebeu irradiação. A mensuração do volume tumoral foi realizada através de um paquímetro e acompanhada durante 7 dias, utilizando a fórmula: V= 0,5.C.L2 (1) Onde: V é o volume em cm³, C o comprimento e L a largura em cm do tumor. Os dados foram analisados utilizando ANOVA-TwoWay com medidas repetidas seguido do teste de Tukey. A análise de sobrevida foi realizada através do teste de Kaplan-Meier. Resultados e Discussão: A figura 1 apresenta a evolução do volume tumoral para os dois grupos. Durante os dois primeiros dias, o volume tumoral de ambos os grupos permaneceu similar e inferior a 2 cm³. A partir do terceiro dia, os grupos mostraram o mesmo comportamento exponencial de crescimento. Entretanto, após 7 dias, o grupo controle tinha um volume médio de 11,64 ± 0,83 cm³, enquanto que o grupo laser mostrou uma progressão mais lenta e no dia 7 apresentava um volume tumoral aproximadamente 62 % menor em relação ao grupo controle. As curvas de sobrevida foram significativamente diferentes já que 13 dias pós-tratamento, todos os animais do grupo controle foram a óbito. Conclusões: Dentro dos parâmetros utilizados neste estudo, a TLBI foi capaz de inibir a progressão de melanoma em camundongos e aumentar a sobrevida dos animais. O volume do tumor é inversamente proporcional à sobrevida. Estes resultados são promissores para propor a TLBI como alternativa terapêutica em pacientes oncológicos, porém mais estudos são necessários para estabelecer seu uso seguro na prática clínica.

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  • IPEN-DOC 26982

    FERREIRA, E.G. ; MARUMO, J.T. ; VICENTE, R. ; LANGTON, C.A.; DUNCAN, A.J.; WILLIAMS, M.R.. Test methods for cementitious seal materials for borehole disposal. In: ANNUAL WASTE MANAGEMENT CONFERENCE, 43rd, March 5-9, 2017, Phoenix, Arizona, USA. Proceedings... Tempe, Arizona, USA: Waste Management Symposia, 2017. p. 1-13.

    Abstract: The Nuclear and Energy Research Institute (IPEN-CNEN/SP) in Sao Paulo-Brazil, is considering borehole disposal of disused sealed radioactive sources (DSRS), which were used in smoke detectors, lightning arrestors, radiotherapy, industrial gauges, irradiators, and other applications. The current IPEN concept of borehole is a modified BOSS system developed by the International Atomic Energy Agency (IAEA). It differs from the IAEA’s design in that the disposal zone is below 300 m, and the DSRS are placed directly in the disposal packages constituted of stainless steel containers with 1.5 L capacity. A borehole drilled through sediment and granite, stabilized with stainless steel casing and cement grout is proposed for the conceptual model. Standard cement-material test methods and performance specific test methods, including accelerated aging methods, are needed for modeling the performance of the candidate cementitious grouts. A cross-disciplinary team from the USA Savannah River National laboratory is providing technical assistance to IPEN in this performance assessment.

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  • IPEN-DOC 26981

    DONATO JUNIOR, JOSE; FURIGO, ISADORA C.; OREFICE, GABRIEL; RAMOS-LOBO, ANGELA M.; SOARES, CARLOS R.J. ; LIST, EDWARD O.; KOPCHICK, JOHN J.. GH controls glycemia and metabolic adaptations to starvation via neurons that express the leptin receptor. In: ENDOCRINE SOCIETY ANNUAL MEETING AND EXPO, 99th, April 1-4, 2017, Orlando, FL, USA. Abstract... Washington, DC, USA: Endocrine Society, 2017.

    Abstract: Growth hormone (GH) responsive neurons are extensively distributed in many hypothalamic nuclei that also have leptin receptor (LepR)-expressing cells (1). However, whether GH affects metabolic functions regulated by leptin remains unknown. In the present study, we initially performed a co-localization study and confirmed that a large percentage of LepR-expressing neurons are directly responsive to peripherally injected GH in different brain nuclei. Then, we generated mice lacking GH receptor (GHR) specifically in LepR-expressing cells (LepR GHR KO mice). Although LepR GHR KO mice exhibited a similar body weight, food intake, energy expenditure, glucose tolerance and leptin sensitivity compared to control mice, we observed a lower adiposity in mutant mice. LepR GHR KO mice also showed a lower capacity to recover from insulin-induced hypoglycemia and a blunted counterregulatory response evoked by 2-deoxyglucose (2DG) administration. Co-infusion of 2DG with sympathetic blockers, but not parasympathetic blockers, was able to abolish the differences observed between groups. Remarkably, while control mice adapted to a 60% food deprivation period by progressively saving energy, LepR GHR KO mice exhibited a blunted metabolic adaptation to starvation, which led to hypoglycemia and an increased lethality rate, energy expenditure and weight loss, compared to control animals. In order to identify the specific neuronal populations responsible for the observed responses, we generated mice lacking GHR in steroidogenic factor-1 (SF1) cells, which comprises the ventromedial nucleus of the hypothalamus (VMH). SF1 GHR KO mice exhibited a similar metabolic phenotype in the basal condition, compared to littermate controls. On the other hand, SF1 GHR KO mice also showed a lower capacity to recover from insulin-induced hypoglycemia and a blunted counterregulatory response evoked by 2DG. However, metabolic adaptations to starvation were not affected by SF1-specific GHR deletion, which suggests that VMH does not mediate these latter changes. In summary, GHR expression in the brain is required to properly regulate glycemia and energy balance, especially during situations in which GH is highly secreted (e.g., hypoglycemia and food restriction). In addition, our findings revealed a previously unrecognized role of GH to coordinate, together with leptin, the metabolic adaptations to starvation in order to ensure survival, via the same neurocircuitry.

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  • IPEN-DOC 26980

    GALANTE, RAQUEL; REDIGUIERI, CAROLINA F.; KIKUCHI, IRENE S.; VASQUEZ, PABLO ; COLAÇO, ROGERIO; SERRO, ANA P.; PINTO, TEREZINHA de J.A.. Sterilization of chitosan nanogels: the protective role of sugars. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 1720-1720.

    Abstract: A nanosystem designed for biomedical applications (e.g. injectables, ophthalmic solutions) cannot be toxic or irritating and must be sterile [1]. Therefore, sterilization is a critical but needed step, during which adverse effects can occur. Literature is very scarce with respect to sterilization effects on nanostructured systems, and even more in what concerns nanogels [1]. This work aims to evaluate the effect and effectiveness of conventional terminal sterilization methods (steam heat and gamma irradiation) on chitosan hydrogel nanoparticles. Chitosan-tripolyphosphate based hydrogel nanoparticles (CS/TPP), with broad spectrum of possible applications were produced and sterilized in the absence and in the presence of protective sugars (glucose and mannitol). Properties like size, zeta potential, absorbance, morphology, chemical structure and cytotoxicity were evaluated. The obtained results allowed concluding that steam heat is not a suitable method for sterilizing CS/TPP nanogel as it leads to severe degradation of the samples, with the appearance of multiple particle populations of different sizes, and large aggregates and sediments. Gamma rays exposure gave rise to immediate formation of visible sediments. However, upon the addition of protective sugars (glucose and mannitol 5%) a significant increase of the nanogel resistance to radiation was observed. This protective effect could be related with the formation of an antioxidant complex.

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  • IPEN-DOC 26979

    SOUZA, GRACIANO B. de; MULLER, DALIANA; MELLO-CASTANHO, SONIA R.H. ; FALK, GILBERTO; HOTZA, DACHAMIR; RAMBO, CARLOS R.. High surface niobium oxide ambigel for simulated nuclear waste immobilization. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 1773-1773.

    Abstract: Niobium is predominantly found in Brazil, and it is, therefore, of great interest to find new technological applications for Nb and its compounds. It has been demonstrated that porous niobium oxide glasses can be used to trap nuclear waste [1]. Glass frits require high energy processes and high sintering temperature for their production. Ambigels on the other hand can be produced under ambient conditions (~25 °C, 1 atm.) and due to their high specific area they require much lower sintering temperatures, two characteristics that attract their use as hosts for nuclear waste immobilization [2]. In this work, we produced niobium oxide ambigels intended as host matrix for simulated multicomponent liquid nuclear waste. We synthetized ambigels using niobium pentachloride (NbCl5) as precursor, ethanol as solvent and nitric acid as catalyst. Following rapid gelation the gels were left to age in ethanol, passing to hexane through sequential solvent exchange until 100% hexane were reached. In the last step, the gels were dried under ambient conditions for 48 hours. We have produced ambigels with high specific surface area (> 110 m²/g) and amorphous niobium oxide phase. The ambigels were impregnated with saline solutions that simulate a multicomponent nuclear waste. The weight gain after thermal treatment was determined and used as indicator for the amount immobilized. Nb2O5-based ambigels can be used as a mesoporous host matrix for nuclear waste immobilization.

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  • IPEN-DOC 26978

    GALEGO, EGUIBERTO ; SERNA, MARILENE M. ; TATEI, TATIANE Y. ; LIMA, BRUNA R. ; FARIA, RUBENS N. . Green synthesis of ZnO nanostructured electrode for supercapacitor. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 1348-1349.

    Abstract: The electrical double layer capacitor (EDLC), has been extensively investigated for its many applications in electric and electronic devices, due to high power density and long-life cycle. Zinc oxide (ZnO) is a promising candidate for the electrochemical supercapacitor electrode. ZnO is well known to be an active battery electrode material with a high energy density of about 650 Ag-1 [1], but it has the disadvantage of dendrites formation during consecutive cycling, which decreases life cycle. In this paper, we report a relatively straightforward, environmental friendly and low-cost method for preparing ZnO electrodes that consists in two steps. Starting with a ZnO seed layer onto a steel substrate employing the successive ionic layer adsorption and reaction (SILAR) method [2]. Subsequently, a chemical deposition bath was used for the nanostructured ZnO growth. A low temperature SILAR method was used in this study, replacing high temperature and vacuum methods, such as chemical vapor deposition or sputtering, to create an interface region between the conductive steel current collector and the nanostructured ZnO electrode. Scanning electronic microscopy has been employed in the characterization of the two-step produced nanostructured ZnO electrodes. The electrochemical performance of the nanocomposite electrodes has been investigated using cyclic voltammetry (10 to 50) mVs-1 and charge-discharge curves (1 to 20) mAcm-2 in aqueous KOH electrolyte at several concentrations. Cyclic voltammetry exhibited a broad redox peak indicative of typical reversible redox reaction of ZnO with the K+, responsible for the faradaic reactions in the supercapacitor. The enhanced electrochemical performance has been attributed to the synergistic effects of pseudo-capacitance behavior of the ZnO phase grown on the ZnO seeds and to the nanostructured features of the electrode.

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  • IPEN-DOC 26977

    BONICIO, HERMANO A.; FLORIO, DANIEL de; FONSECA, FABIO C. . Thin layer deposition through Ink Jet technology, for application in SOFC. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 1311-1311.

    Abstract: In the present work, the objective is to develop a film deposition technique with micrometric thickness. For this, the adaptation of a commercial inkjet printer was done by designing and constructing a base with rails so that it runs over the sample. At the same time, a study of rheological characterization of the commercial inks, contained in original ink jet cartridges, was carried out for the development and deposition of a ceramic suspension, which contains the precursors of the desired material for the formation of the thin layer. Finally, some depositions of SOFC electrolytes were performed, and after the densification step, the cells were characterized by the impedance spectroscopy and also scanning electron microscopy. It was observed the formation of a dense and uniform layer, with thickness of the order of 10 μm.

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  • IPEN-DOC 26976

    TINTI, VICTOR B.; FONSECA, FABIO C. ; FLORIO, DANIEL de. A new technique to determine catalysts amounts with ferromagnetic behaviour. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 337-338.

    Abstract: Metallic nanoparticles can be applied at several different areas, from magnetic contrast to fuel production. Nickel is already applied in breaking H-C bounds to the produce H2 for application in SOFC. The miniaturization of the catalyst into nanoparticles can enhance thermal stability and performance. Nowadays, there are some difficulties related to the synthesis, stabilization and characterization of the nanometric system. A new technique to obtain highly disperse nanoparticles consist in the exsolution of previously solubilized ions in a ceramic matrix [1]. Exsolved nanoparticles show higher stability and better catalytic performance, if compared with only deposited particles. The quantization of nanoparticles in the material, using XRD, SEM, TEM or EDS analyses, is not a simple task due limitations of each technic. Magnetic measurements are quick and can provide a precise amount of ferromagnetic particles present in the sample. To demonstrate this technique, samples with compositions (La1-xSrx)(Cr1-yNiy)O3 (x and y = 0, 0.1 and 0.2) were synthesized by complex polymerization method. The morphology of the obtained powder was observed with SEM and TEM. The samples were reduced at 800 °C and 900 °C in pure hydrogen, in order to create metallic nickel nanoparticles by exsolution. Magnetic analyses were conducted with a SQUID/VSM. Reduced samples show a coupling between the ferromagnetic and antiferromagnetic behaviour and a higher temperature of Neel, when compared with thermally treated air. Using as magnetic measurements results was possible to determine higher amounts of Ni, if compared with values obtain from Rietveld refinement.

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  • IPEN-DOC 26975

    SANTIAGO, ELISABETE I. ; MATOS, BRUNO R. ; DRESCH, MAURO A.; ISIDORO, ROBERTA A. ; FONSECA, FABIO C. . Advances on Nafion-based composites for high temperature proton exchange membrane fuel cells. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 55-55.

    Abstract: PEMFC (Proton exchange membrane fuel cell) is considered a promising and efficient hydrogen fuelled electrical power source. However, PEMFC faces several technical problems, such as sluggish electrode reaction kinetics involving the limiting rate of the oxygen reduction and alcohol oxidation reactions, and high resistance to ion transport that could be surpassed with increasing of the operation temperature. The main impediment for such a temperature increase is the water dependent performance of the state-of-the-art Nafion electrolyte. Above 80 ºC water starts to evaporate considerably and Nafion microdomains begin to shrink, disrupting its percolative structure, leading from a conductor to insulator transition. In this work, the incorporation in-situ or ex-situ of an inorganic phase with hydrophilic properties, such as TiO2 and SiO2, into Nafion membranes has been evaluated as an interesting alternative to produce stable electrolytes able to operate at higher temperatures (130o C). The physical-chemistry and electrochemical characterisation has shown that the inorganic particles located in both the nonionic and ionic regions of the ionomer have important contributions to enhanced thermal stability and water uptake. Such features resulted in significant improvements of the PEMFCs using composite electrolytes tested at high operating temperature and low relative humidity. In addition, remarkable enhancement on the DEFC (Direct Ethanol Fuel Cell) performance (122 mW cm‑2) has been obtained as a result of an increase of ethanol oxidation reaction rate promoted by the combination of enhanced catalyst activity and high temperature of operation using stable composite Nafion-SiO2 electrolytes.

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  • IPEN-DOC 26974

    LOBO, RAQUEL de M. ; MORCELLI, APARECIDO E.; SOUZA, SAUL H.; PADILHA, ANGELO F.; ANDRADE, ARNALDO H.P. de . Slant fracture surface in 7075 aluminum alloy tensile specimens. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 800-800.

    Abstract: Rectangular specimen of a 7075 aluminum alloys in three different thermal treatment conditions were tested in a tensile equipment. The samples tested exhibit slant fracture surfaces. Some of the samples presented Portevin-Le Chatelier (PLC) effect. In fact, for aluminum alloys, the PLC phenomenon may occurs even at room temperature. It leads to strain localization and deformation band formation. In this work, the occurrence of slant fracture is studied by scanning electron microscopy and an attempt is done to correlate their presence with the PLC bands.

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  • IPEN-DOC 26973

    BALDAN, RENATO; SILVA, ANTONIO A.A.P.; NUNES, CARLOS A.; COUTO, ANTONIO A. ; GABRIEL, SINARA B.; ALKMIN, LUCIANO. Microstructural changes during solution and aging heat-treatments of MAR-M246 superalloy. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 823-823.

    Abstract: Solution and aging heat-treatments play a key role for the application of the superalloys. The aim of this work is to evaluate the microstructure of the MARM246 nickel-based superalloy solutioned at 1200 and 1250°C for 330 min and aged at 780, 880 and 980 °C for 5, 20 and 80 h. The γ′ solvus, solidus and liquidus temperatures were calculated with the aid of the JMatPro software (Ni database). The as-cast and heat-treated samples were characterized by SEM/EDS and SEMFEG. The γ′ size precipitated in the aged samples was measured and compared with JMatPro simulations. The results have shown that the sample solutioned at 1250°C for 330 min showed a very homogeneous γ matrix with carbides and cubic γ′ precipitates uniformly distributed. The mean γ′ size of aged samples at 780 and 880 °C for 5, 20 and 80 h did not present significant differences when compared to the solutioned sample. However, a significant increasing in the γ′ particles was observed at 980 °C, evidenced by the large mean size of these particles after 80 h of aging heat-treatment.

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  • IPEN-DOC 26972

    MOURA, TIAGO F.A.; NAVARRO, RAPHAELLA; SHIOTSUKI, AUGUSTO K.; UTIYAMA, ANA P.M.S.; ICHIKAWA, RODRIGO U. ; MATOS, RONALDO V.R.; CASTRO, GUSTAVO R.; YOSHITO, WALTER K. ; MARTINEZ, L.G. ; MIRANDA, JOSE R.A.; SAEKI, MARGARIDA J.. The influence of iron content and alkaline concentration on Mn0.75Zn0.25FeyO4 structure, surface charge and acb response. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 578-578.

    Abstract: Nanotechnology applied on magnetic material provide a good opportunity to develop biomaterials as tracers for Alternating Current Biosuceptometry (ACB)and Magnetic Resonance Imaging (MRI) to diagnose certain diseases as cancer. The magnetic nanoparticles can still constitute drug carrier systems and hyperthermia agent for cancer treatment. Neverthless, the efficiency for therapy and diagnosis depends on the magnetic susceptibility. In this work, the ferrite nanoparticles with nominal composition Mn0.75Zn0.25FeyO4, where 1.5 ≤ y ≤ 2.8, were synthesized by the co-precipitation method and, the influence of iron content and concentration of precipitating agent on the structure, ACB response and surface charge was analyzed. It was noted that the synthesis using alkaline metal hydroxide between 0.1, 0.15 and 0.2 mol/L provides single-phase materials [ICSD 28515 (PDF - 742 402), space group Fd3m]. The higher concentration (0.25 mol/L) leads to materials with higher crystallinity and similar ACB response to those precipitated by lower concentration base, despite the secondary phase. A surface charge of 30 mV in module was achieved, which decreased as the concentration of the precipitating agent increased.

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  • IPEN-DOC 26971

    KHAN, LATIF U.; BRITO, HERMI F.; MURACA, DIEGO; COSTA, LUELC S. da; FELINTO, MARIA C.F. da C. . Red-emitting magnetic mesocomposites of Ag-decorated Fe3O4@SiO2 nanoflowers coated with Y2O3:Eu3+: study of iron oxide induced luminescence quenching. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 127-127.

    Abstract: The new multistep approach for co-assembling magnetic iron oxide nanoflowers with red-emitting Y2O3:Eu3+ to form magneto-luminescent mesocomposites was reported. The Fe3O4 core particles prepared by solvothermal method were layered with SiO2 shell and decorated with small size spherical Ag nanoparticles as well as further coated with Y2O3:Eu3+ lluminophore. The nanoflower shape Fe3O4 core of size ~110 nm and crystalline cubic structure of bifunctional ironoxide@ Y2O3:Eu3+, Fe3O4@SiO2@Y2O3:Eu3+ and Fe3O4@SiO2-Ag@Y2O3:Eu3+ (1 mol%) mesocomposites were confirmed from X-rays diffraction, EDS spectra and transmission electron microscopy images. The static magnetic measurements supported and manifested nonsuperparamagnetic behavior of the materials at 300 K. The iron oxides are usually luminescent quencher, therefore, the photoluminescence properties based on the emission spectral data and luminescence decay curves were studied. In addition, experimental intensity parameters (Ωλ), lifetimes (τ), emission quantum efficiencies as well as radiative (Arad) and non-radiative (Anrad) decay rates were also calculated, in order to probe the local chemical environment of the Eu3+ ion and better understand the phenomena of iron oxide induced luminescence quenching. The highest value of the quantum efficiency = 74 %, for the a-Fe2O3@Y2O3:Eu3+ (1 mol%) among all the luminescent and magnetic mesocomposites suggests that Fe2O3 is induced lower luminescence quenching then Fe3O4. Though, the thin layer of SiO2 spacer is caused of increase the quantum efficiency, whereas the Ag is further enhanced the luminescence quenching by energy transfer form Eu3+ ion to the Ag nanoparticles. These novel Eu3+ mesocomposites may act as a red emitting layer for magnetic and light converting molecular devices.

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  • IPEN-DOC 26970

    SERNA, MARILENE M. ; GALEGO, EGUIBERTO ; RAMANATHAN, LALGUDI V. ; FARIA, RUBENS N. . Morphology of nanostructured thin films of ZnO fabricate from SILAR method. In: BRAZIL MRS MEETING, 16th, September 10-14, 2017, Gramado, RS. Abstract... São Carlos, SP: Aptor Software, 2017. p. 1260-1260.

    Abstract: The utilization of the ZnO in the nanotechnology is widely spread due to its superior properties, such as wide direct bang gap (~3.37eV), high exciton binding energy of 60 meV, non-toxicity and low cost [1]. The hexagonal crystalline structure allows obtaining a larger diversity morphologies and this allows its utilization in: UV lasers, piezoelectric crystal, chemical sensor, gas sensor, light emitting diode, photo detectors, and solar cells. One such morphology of ZnO thin film is the one-dimensional (1D) sub-micron rods or nanorods and nanowires, which has attracted interest due to a larger surface area and high aspect ratio. In the solar cell the ZnO has been utilized in the electrode for the dye-sensitized cell in substitution of TiO2. In this study, ZnO nanostructured thin films were prepared by successive ionic layer adsorption and reaction (SILAR) on SnO2-coated glass substrates [2]. In this procedure, the substrate is immersed in successive aqueous baths containing zinc nitrate hydrate and/or hexamethylenetetramine, hydrogen peroxide and triethanolamine. The pH solution was adjusted by addiction of ammonium hydroxide. At a low zinc nitrate concentration of 0.01M the surface is formed by individual nucleus. At a concentration of 0.02 M nanorod arrays were shown and this morphology is of special interest for solar cells application, but the deposition time used in this experiment was insufficient to promote the desired thickness. At a higher concentration of 0.03 M rice like branches morphology was observed but nanorods formation in the flowers was also present. The angular petals suggest that the growth was taken on polar face. For DSSCs applications the thin films prepared in 0.02 M solution was found to be the best choice.

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  • IPEN-DOC 26969

    SANTIAGO, E.I. ; PONCE-GONZALEZ, J.; WANG, L.; VARCOE, J.R.. Células a combustível de membrana de troca aniônica de alto desempenho baseadas em ionômeros sólidos / High performance anion exchange membrane fuel cells based on ionomers. In: SIMPÓSIO BRASILEIRO DE ELETROQUÍMICA E ELETROANALÍTICA, 21., 17-21 de abril, 2017, Natal, RN. Resumo... Campinas, SP: Galoá, 2017.

    Abstract: Alkaline polymer electrolyte fuel cells (APEFC) have received increased attention in recent years as an alternative to well-established PEMFC because the alkaline medium enables more efficient and faster electrochemical reactions using nonnoble catalysts. The development of stable and conductive polymeric materials employed as anion-exchange membranes (AEM) and anion-exchange ionomers (AEI) has been the focus of substantial efforts. In this work, ETFE (poly(ethylene-cotetrafluoroethylene)) powders were electron-beamed radiation-grafted (RG) with vinylbenzyl chloride (VBC) monomer and then either aminated with trimethylammonium (TMA) or N-methylpyrrolidinium (MPY). The resulting powders were employed as the AEI in the gas diffusion electrodes in single cell H2/O2 APEFCs (along with RG-AEMs). The results showed that the degree of grafting (DoG), and consequently the ionexchange capacity (IEC), are strongly dependent on the radiation dose. RG-AEI made from ETFE irradiated at 100 kGy (total absorbed dose) and functionalised with TMA (ETFE100TMA) and MPY (ETFE100MPY) exhibit IEC values of 2.05 and 1.91 meq.mol-1, respectively. The H2/O2 power density curves (Fig. 1) for APEFC with ETFE100TMA in both anode and cathode; ETFE100MPY in both anode and cathode, and ETFE100TMA in anode and ETFE100MPY in cathode, revealed high performances (> 800 mW cm-2). The best performance was observed for with the ETFE100TMA anode and ETFE100MPY cathode (maximum power density of 1.1 W.cm-2).

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  • IPEN-DOC 26968

    MATOS, B.R. ; SANTIAGO, E.I. ; TOSCO, B.; REY, J.F.Q.; SILVA, J.S. da ; SCHADE, U.; PUSKAR, L.; AZIZ, E.F.; FONSECA, F.C. . Efeito da relaxação do polímero na cristalinidade, fase iônica e formação de grupos sulfônicos anidridos no Nafion / Effect of the polymer relaxation on the crystallinity, ionic phase and sulfonic anhydrides formation of Nafion. In: SIMPÓSIO BRASILEIRO DE ELETROQUÍMICA E ELETROANALÍTICA, 21., 17-21 de abril, 2017, Natal, RN. Resumo... Campinas, SP: Galoá, 2017.

    Abstract: A relação entre as propriedades estruturais e elétricas de amostras de Nafion preparadas sob tratamento térmico em diferentes temperaturas (220 > T > 100 °C) foi investigada por espectroscopia no infravermelho (FTIR), espalhamento de raios-X em baixo ângulo (SAXS), calorimetria diferencial exploratória (DSC), análise dinâmico-mecânica (DMA) e espectroscopia de impedância (IS). Os resultados combinados de FTIR, SAXS, DSC, DMA revelaram que o tratamento térmico em baixas umidades relativas altera a morfologia do Nafion irreversivelmente devido a três características principais: i) o rearranjo das ligações de hidrogênio; ii) o reordenamento da fase cristalina; e iii) a formação de grupos sulfônicos anidridos. No entanto, a formação dos grupos anidridos é revertida pela reacidificação da membrana em soluções ácidas. O aspecto mais importante da dinâmica dos três processos descritos é que tais alterações são aceleradas acima de uma temperatura crítica: a temperatura de término da transição α do Nafion (Tendα ~ 160 °C). A transição α é atribuída ao enfraquecimento das interações eletrostáticas existentes entre os grupos sulfônicos do Nafion, que permitem a movimentação de longo alcance das cadeias poliméricas [1]. Este resultado indica que a maior dinâmica das cadeias do polímero em T > Tendα é o principal fator envolvido na modificação irreversível da morfologia do Nafion. As alterações da estrutura das ligações de hidrogênio afetaram negativamente as propriedades elétricas do Nafion. O aumento da temperatura de tratamento térmico reduz a condutividade protônica e aumenta a energia de ativação do transporte de cargas no Nafion. Tais resultados são relevantes para a preparação de conjuntos eletrodos-membrana (MEA) e para a operação de células a combustível de eletrólito polimérico (PEFC) em altas temperaturas [1].

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  • IPEN-DOC 26967

    SANTOS, VINICIUS T. dos; SANTOS, GIVANILDO A. dos; NAKAMOTO, FRANCISCO Y.; SILVA, MARCIO R. da; FRANCO, ANTONIO T.R.; COUTO, ANTONIO A. . Influência das variáveis térmicas de solidificação na microestrutura e dureza da liga bronze alumínio níquel CuAl10Ni5Fe5 / Influence of thermal variables of solidification on the microstructure and hardness of nickel aluminum bronze alloy CuAl10Ni5Fe5. In: CONGRESSO BRASILEIRO DE ENGENHARIA DE FABRICAÇÃO, 9., 26-29 de junho, 2017, Joinville, SC. Anais... Rio de Janeiro, RJ: Associação Brasileira de Engenharia e Ciências Mecânicas, 2017.

    Abstract: O objetivo deste trabalho é obter correlações entre a microestrutura e dureza da liga Bronze Alumínio Níquel CuAl10Ni5Fe5 em função das variáveis térmicas de solidificação. Estas variáveis são responsáveis pela formação das fases e intermetálicos presentes no Bronze Alumínio Níquel, os quais interferem diretamente nas propriedades mecânicas do material. A liga CuAl10Ni5Fe5 foi solidificada em um dispositivo com sistema ascendente sob condições não-estacionárias de fluxo de calor. O calor foi extraído direcionalmente através de uma base de aço ABNT 1020 refrigerada a água. No que diz respeito à análise da microestrutura, utilizou-se microscopia eletrônica de varredura, permitindo a verificação das morfologias das fases e intermetálicos. As variáveis térmicas de solidificação geram resultados referentes à velocidade de deslocamento da isoterma liquidus e à taxa de resfriamento. A propriedade mecânica foi avaliada por meio de ensaio de dureza em toda extensão longitudinal da peça solidificada, a qual apresenta a formação das fases e intermetálicos formados por meio das condições de solidificação impostas pelo sistema metal/molde. A microestrutura e dureza são correlacionadas com as variáveis térmicas de solidificação, enfatizando a importância das taxas de resfriamento na formação das fases e intermetálicos da liga CuAl10Ni5Fe5. O resultado deste trabalho demonstra que, quanto maior a taxa de resfriamento, maior é o resultado obtido de dureza.

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  • IPEN-DOC 26966

    DEETER, MERRITT N.; EMMONS, LOUISA K.; MARTINEZ-ALONSO, SARA; WIEDINMYER, CHRISTINE; ARELLANO, AVELINO F.; FISCHER, EMILY V.; GONZALEZ-ALONSO, LAURA; VAL MARTIN, MARIA; GATTI, LUCIANA ; MILLER, JOHN B.; GLOOR, MANUEL; DOMINGUES, LUCAS G. ; CORREIA, CAIO S. de C. . Progress towards improved MOPITT-based biomass burning emission inventories for the Amazon Basin. In: AMERICAN GEOPHYSICAL UNION FALL MEETING, December 12-16, 2016, San Francisco, CA, USA. Abstract... Washington, DC, USA: American Geophysical Union, 2016.

    Abstract: The 17-year long record of carbon monoxide (CO) concentrations from the MOPITT satellite instrument is uniquely suited for studying the interannual variability of biomass burning emissions. Data assimilation methods based on Ensemble Kalman Filtering are currently being developed to infer CO emissions within the Amazon Basin from MOPITT measurements along with additional datasets. The validity of these inversions will depend on the characteristics of the MOPITT CO retrievals (e.g., retrieval biases and vertical resolution) as well as the representation of chemistry and dynamics in the chemical transport model (CAM-Chem) used in the data assimilation runs. For example, the assumed vertical distribution ("injection height") of the biomass burning emissions plays a particularly important role. We will review recent progress made on a project to improve biomass burning emission inventories for the Amazon Basin. MOPITT CO retrievals over the Amazon Basin are first characterized, focusing on the MOPITT Version 6 “multispectral” retrieval product (exploiting both thermal-infrared and near-infrared channels). Validation results based on in-situ vertical profiles measured between 2010 and 2013 are presented for four sites in the Amazon Basin. Results indicate a significant negative bias in MOPITT retrieved lower-tropospheric CO concentrations. The seasonal and geographical variability of smoke injection height over the Amazon Basin is then analyzed using a MISR plume height climatology. This work has led to the development of a new fire emission injection height parameterization that was implemented in CAM-Chem and GEOS-Chem.. Finally, we present initial data assimilation results for the Amazon Basin and evaluate the results using available field campaign measurements.

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  • IPEN-DOC 26965

    ZAHN, GUILHERME S. ; GENEZINI, FREDERICO A. ; RIBEIRO JUNIOR, IBERE S. ; FAGIONATO, ESNEL A. . On the use of gamma-gamma coincidence to detect very low activities. In: BRAZILIAN MEETING ON NUCLEAR PHYSICS, 40th, September 3-7, 2017, Campos do Jordão, SP. Abstract... São Paulo, SP: Sociedade Brasileira de Física, 2017. p. 1-1.

    Abstract: The detection of very low gamma ray activities is a delicate task, and very important in environmental radiation studies, for instance. It usually requires the use of low-background shielding, as the long counting times required usually make the background subtraction quite tricky, and often result in rather high experimental uncertainties. In this work a different approach is tested, where a two-detector gamma-gamma coincidence system is used to eliminate essentially all of the background continuum - at the cost of reduced overall efficiency and, more importantly, requiring that the radionuclide to be studied presents useful gamma-gamma coincidences. Two distinct methods of analysis are tested, either using an "open-window" coincidence where an event is registered whenever any event is registered in the other detector, or using a strict coincidence analysis, where a valid coincidence between two gamma-rays from the same decay are required; this allow for a discussion on the advantages and problems of each method, as well as for an experimental assessment of the performance of such a system.

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  • IPEN-DOC 26964

    GENEZINI, FREDERICO A. ; ZAHN, GUILHERME S. ; MORALLES, MAURICIO ; MOREIRA, EDSON G. . Celebrating IEA-R1 first criticality. In: BRAZILIAN MEETING ON NUCLEAR PHYSICS, 40th, September 3-7, 2017, Campos do Jordão, SP. Abstract... São Paulo, SP: Sociedade Brasileira de Física, 2017. p. 1-1.

    Abstract: Early in 1956 USP and CNPq established a cooperation agreement and in the middle of the same year, the Atomic Energy Institute (IEA) was founded. Its primary task was to install the research nuclear reactor purchased from the American company Babcock & Wilcox in the context of the “Atoms for Peace” Program. Another major task was to train reactor operators and users of the new facility. The first start-up was in September 16, 1957, being the first criticality achieved in the Southern hemisphere. IEA-R1 is a pool type, light water cooled and moderated, graphite reflected research reactor. Although designed to operate continuously up to 5 MW, it operated at 2 MW power during 40 years and afterwards it has been operating at 5MW. IEA R1 has several uses, such as radioactive isotope production by neutron flux irradiation up to 10(14)cm(-2)s(-1), for health and industry applications; research and development using radioactive samples and neutron beams (8 radial and 2 tangential beam ports). This year we celebrate the 60th anniversary of the first criticality of the IEA-R1 research reactor and due to a continuous modernization program, it is expected to operate for another long time period.

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  • IPEN-DOC 26963

    PASCOAL, ERIC; KLEINGESINDS, EDUARDO; MOURA, ESPERIDIANA ; LUGAO, ADEMAR ; RODRIGUES, RITA. Sugar produced from corncob pretreated with the combination of electron beam irradiation and enzymes. In: AMERICAN CHEMICAL SOCIETY NATIONAL MEETING & EXPOSITION, 253rd, April 2-6, 2017, San Francisco, CA, USA. Abstract... Washington, DC, USA: American Chemical Society, 2017.

    Abstract: Corncob is a lignocellulosic material composed of cellulose, hemicellulose, and lignin. Cellulose and hemicellulose are polysaccharides constituted of simple sugars (hexoses and pentoses). However, these sugars are difficult to access, due to the presence of lignin, which is a polyphenolic molecule that provides a high recalcitrance to plant tissue. An appropriate biomass pretreatment disrupts the hydrogen bonds in crystalline cellulose, breaks down cross-linked matrix of hemicelluloses and lignin, and raises the porosity and surface area of cellulose for subsequent enzymatic hydrolysis. There are several pretreatment methods including, physical pretreatment (electron beam irradiation, grinding and milling, microwave, and extrusion), chemical pretreatment (alkali, acid, organosolv, ozonolysis, and ionic liquid), physico-chemical pretreatment (steam explosion, liquid hot water, ammonia fiber explosion, wet oxidation, and CO2 explosion), and biological pretreatment. This study evaluated electron beam irradiation (EB) in combination with enzymatic hydrolysis on corncob at different grain size to produce sugars. Dry biomass samples after characterization were exposed to EB radiation doses of 0, 30, 50, 70, 100, and 200 kGy. The pretreated biomass samples were enzymatically hydrolyzed using the Cellic CTec2 from Novozymes. The structural changes and degree of crystallinity of the pretreated biomass were studied by FTIR, DRX, DSC, TG and SEM analyses. Corncob in natura showed 6.3 % extractives, 40.3 % cellulose, 31.8 % hemicellulose, 17.3 % lignin, and 0.7 % ash. The EB in combination with enzymatic hydrolysis of corncob is an environmentally sound biomass pretreatment.

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  • IPEN-DOC 26962

    FREITAS, TARIK ; COIADO, RENATA ; LAZO, GISELE; OLIVEIRA, RENE ; MOURA, ESPERIDIANA . Residues from agroindustry as reinforcement in foams based on PBAT/PLA blend. In: AMERICAN CHEMICAL SOCIETY NATIONAL MEETING & EXPOSITION, 253rd, April 2-6, 2017, San Francisco, CA, USA. Abstract... Washington, DC, USA: American Chemical Society, 2017.

    Abstract: Nowadays, agroindustry residues have attracted great attention in both the academic and industrial worlds. In fact, biodegradable polymers reinforced with residues derived from renewable sources, as avian eggshell waste and ashes from the burning of sugarcane bagasse are economically and ecologically attractive materials to produce a new class of bio-products with eco attributes, which make them environmentally friendly, completely degradable and sustainable. In Brazil, the food industry generates every year huge amounts of avian eggshell waste, an industrial byproduct containing 95 % of calcium carbonate, and its disposal constitutes a serious environmental hazard. Tons of ashes are produced from the burning process of sugarcane bagasse to produce energy in Brazilian sugar and bioethanol industries. These ashes, which are not rich in nutrients for the crop, are usually mixed with organic fertilizers or disposed of in nature without efficient management. However, these ashes containing about 94 % of silica. This study aims to the development of bio-foams from PBAT/PLA blend reinforced with bio-calcium carbonate nanoparticles from eggshells and green-silica nanoparticles. Composites were obtained by melting extrusion process, blending PBAT/PLA with 3 % of bio-calcium carbonate nanoparticles and 3 % of green-silica nanoparticles. The composites were then extruded in a Rheomex 332p single special screw for foaming. Samples were submitted to tensile and compression tests, MFI, DSC, XRD and SEM-FEG analyses.

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  • IPEN-DOC 26961

    SANTOS, CAMILA F.R.T.T. ; SILVA, TATIANE B. de S.C. da ; COTRIM, MARYCEL E.B. ; PIRES, MARIA A.F. . Fatores de emissão atmosférica e análise de significância aplicada na gestão da qualidade do ar no campus do IPEN/CNEN-SP / Atmospheric emission factors and significance analysis applied to the air quality management in the IPEN / CNEN-SP campus. In: ENCONTRO INTERNACIONAL SOBRE GESTÃO EMPRESARIAL E MEIO AMBIENTE, 18., 5-6 de dezembro, 2016, São Paulo, SP. Anais... São Paulo, SP: Faculdade de Economia, Administração e Contabilidade da Universidade de São Paulo - FEA USP, 2016.

    Abstract: Devido ao compromisso com a melhoria do meio ambiente, aliado às crescentes exigências dos órgãos ambientais, e a necessidade de identificar a contribuição de cada atividade/processo desenvolvido em institutos de pesquisas, quanto ao impacto destes à qualidade do ar, este trabalho tem a finalidade de desenvolver um modelo de inventário e aplicar uma metodologia de cálculo, que permita estimar a emissão de poluentes atmosféricos, decorrentes das atividades dos centros de pesquisa e desenvolvimento do Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP). O estudo foi motivado pela ausência de metodologias de cálculo de emissões atmosféricas específicas para fontes fixas como capelas de exaustão. Para a elaboração dos cálculos foram adotados os fatores de emissão e a equação descrita na AP-42 da EPAEnvironmental Protetion Agency. Foram utilizadas como abordagens de cálculo de emissões: a) Mensuração direta (por meio do inventário de emissões atmosféricas); e b) Estimativa de emissões (utilizando estimativa da taxa de emissão calculada a partir do fator de emissão apropriado). Como produto final obteve-se um inventário de emissões atmosféricas de fontes fixas da instituição e estimou-se a emissão atmosférica do Centro de Química e Meio Ambiente (CQMA) a fim de estabelecer de forma efetiva o Programa de Monitoramento e Controle de Emissões Atmosféricas (PMEA – IPEN), servindo de base para outras instituições de Pesquisa, Desenvolvimento & Inovação.

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  • IPEN-DOC 26960

    BARBOSA, HELLIOMAR P.; SILVA, IVAN G.N.; FELINTO, MARIA C.F.C. ; TEOTONIO, ERCULES E.S.; MALTA, OSCAR L.; BRITO, HERMI F.. White light emission materials based on simultaneous Tb3+, Eu3+ and Dy3+ doping in CaWO4 single-phased. In: WORLD CHEMISTRY CONGRESS, 46th; ANNUAL MEETING OF THE BRAZILIAN CHEMICAL SOCIETY, 40th; IUPAC GENERAL ASSEMBLY, 49th, July 07-14, 2017, São Paulo, SP. Abstract... Durham, NC, USA: International Union of Pure and Applied Chemistry, 2017.

    Abstract: Tungstates activated by trivalent rare earth ions (RE3+) can be used for many optical devices [1]. Over the last decades, the solid-state lighting sources based on phosphor converted white lightemitting diodes (pc-WLEDs) has improved to overtake fluorescent lighting types because of many advantages such as high ecofriendliness, brightness, low power consumption and fast response time [2]. Here we report preparation and spectroscopic properties of the single phase new highly luminescent white emitting of the Tb3+/Eu3+/Dy3+ triply-doped CaWO4 material. The CaWO4:xTb3+,xEu3+,xDy3+(x mol% of the Ca2+ amount) materials were prepared by fast coprecipitation method at room temperature with stoichiometry aqueous solutions of Na2WO4, CaCl2 and RECl3 (RE3+: Tb, Eu and Dy). The XPD measurements revealed the CaWO4:RE3+ particles belong to the tetragonal scheelite phase with I41/a (#88) space group. The emission spectra exhibit only narrow emission bands arising from the doping Tb3+, Dy3+ and Eu3+ ions. These emission bands are assigned to the 4f transitions from the 4F9/2 (Dy3+), 5D4 (Tb3+) and 5D0 (Eu3+) emitting states to their energy levels corresponding to (in nm): 702 5D07F4(Eu3+), 655 5D07F3(Eu3+), 615 5D07F2(Eu3+), 592 5D07F1(Eu3+), 575 4F9/26H13/2(Dy3+), 544 5D47F5(Tb3+), 488 5D47F6(Tb3+), 478 4F9/26H15/2(Dy3+) (Fig. left). The presence of the emission bands assigned to the doping Dy3+, Tb3+ and Eu3+ ions suggests clear evidence of nonradiative energy transfer from 4F9/2 (Dy3+)5D4 (Tb3+)5D0 (Eu3+) emitter states (Fig. center). The white light emission was mainly reached for 5.0 mol% RE3+ with x: 0.333; y: 0.352 CIE (Commission Internationale l'Éclairage) coordinates (Fig. right). These phosphors could be suitable as triply-doped white light emitters with only single-phased for solid state lighting applications. Since warm white light is preferred for reading, while cold white light is preferred for public lighting the tunability of this single-phase emitting phosphor exhibit promising applications for solid-state lighting.

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  • IPEN-DOC 26959

    FONSECA, THAIS N. ; MOURA, EDUARDO de ; GERALDO, AUREA B.C. . Study of Bixin oxidation by ionizing irradiation. In: WORLD CHEMISTRY CONGRESS, 46th; ANNUAL MEETING OF THE BRAZILIAN CHEMICAL SOCIETY, 40th; IUPAC GENERAL ASSEMBLY, 49th, July 07-14, 2017, São Paulo, SP. Abstract... Durham, NC, USA: International Union of Pure and Applied Chemistry, 2017.

    Abstract: Brazil is the world's largest producer of annatto, followed by Kenya and Peru (CORLETT, 2007). The fruit of the annatto tree is constituted by a capsule containing external spines and internal seeds with reddish coloration, providing a natural pigment which is environmentally efficient, being able to replace synthetic pigments and dyes. The active substance of the pigment is Bixin, which is a type of carotenoid which constit utes a greater percentage of pigment in these seeds and has a lipo soluble character ( CUSTODIO , 2002 ). Bixin reacts with NaOH in a saponification reaction giving norbixin, which is water soluble. It is known that the destination of the dye extracted from t he fruit is intended for industry, especially the food industry. The culture of annatto tree brings prospects of development of agricultural programs for medium and small producers, which are able to use decadent areas of other crops. In addition to the fo od sector, new applications for the pigment helps the development of family farming (BERTOLIN, 2016). The pigment extracted from annatto undergoes a natural oxidation; this work aims to evaluate this phenomenon and also the oxidation of the pigment after the irradiation process. This work also evaluates of the how the oxidation process is affected by irradiation and the modifications introduced to irradiated pigments. Irradiated and non irradiated samples were characterized by UV vis s pectrophotometry a nd infrared spectroscopy (FTIR). The results are then discussed.

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  • IPEN-DOC 26958

    TEIXEIRA, PAULA dos S. ; MOURA, EDUARDO de ; GERALDO, AUREA B.C. . Irradiation of cellulosic waste from annatto seeds (Bixa orellana L.) for application in polymeric composites. In: WORLD CHEMISTRY CONGRESS, 46th; ANNUAL MEETING OF THE BRAZILIAN CHEMICAL SOCIETY, 40th; IUPAC GENERAL ASSEMBLY, 49th, July 07-14, 2017, São Paulo, SP. Abstract... Durham, NC, USA: International Union of Pure and Applied Chemistry, 2017.

    Abstract: The study o f natural vegetable, fiber reinforced polymeric composites became popular in the last decades since because this type of material enables the reduction of both the biomass waste and the cost of the final polymer product (MARINELLI, 2008). Plant fibers are plenty, low cost, they feature biodegradability and renewability. Moreover, cellulose polymer composites are more resistant to flection and impacts than the same base polymer material (FONSECA, 2005; HILLIG, 2008). Specifically, cellulose from annatto seed s is present in concentration at around 40 45%, which becomes important for industrial use (ANSELMO, 2008). In this work, the bagasse from annatto seeds after reddish pigment removal has being used to obtain high density polyethylene (HDPE) composites. T he original raw material underwent a pretreatment that extracted the components from seeds such as residue of remaining pigment, sugars, proteins and acid fats. The remaining fibers have been dried and mashed, and then submitted to electron beam irradiatio n with doses of 30 kGy, 50 kGy and 70 kGy to verify the effect of the radiation on the cellulose structure and its subsequent effect on the incorporation into polymer matrix. The study covered the extrusion of these fibers (irradiated and non irradiated) i n the ratio of 1 % to 5 % with HDPE. The sample characterization has been done by infrared spectrometry (FTIR), thermal degradation (TG) and mechanical tensile tests. The results are then discussed.

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  • IPEN-DOC 26957

    FERREIRA, MAIARA S. ; MOURA, EDUARDO de ; GERALDO, AUREA B.C. . Effect of irradiation on the molar mass of chitosan from crab shells of Charybdis hellerii. In: WORLD CHEMISTRY CONGRESS, 46th; ANNUAL MEETING OF THE BRAZILIAN CHEMICAL SOCIETY, 40th; IUPAC GENERAL ASSEMBLY, 49th, July 07-14, 2017, São Paulo, SP. Abstract... Durham, NC, USA: International Union of Pure and Applied Chemistry, 2017.

    Abstract: The importance of determining the molar mass of polymers is closely related to the size of the chain which is a controlling factor in the evolution of solubility, elasticity, fiber formation and mechanical strength properties. There are several methods used to determine the molar mass and they are divided into relative or absolute. Relative methods as viscosimetry require calibration with samples of molar mass known, whereas absolute methods as osmometry do not require it. The importance of molar mass determination is related to its high influence on the properties of chitosan, such as bacterial activity. There are some studies that show that the use of chitosan is more efficient in the inhibition of bacteria than the use of the oligomers that form the same (NO et al., 2002; HIRANO et al., 1989) and that the molar mass required for the inhibition of microorganisms should be greater than 10000 Da (SHAHIDI et al., 2000). The minimum inhibitory concentration of chitosan ranges from 0.005 - 0.1% and depends on the species of bacteria, the molar mass and the pH of the chitosan preparation (GUAN et al., 2001, NO et al., 2002). The method used in this work was the capillary viscosimetry because it is simple, fast and very efficient. For each sample, four dilutions were performed in order to make the extrapolation and determine the intrinsic viscosity. The average viscosity molar mass (Mw) was determined by the Mark-Houwink-Sakurada equation ([ƞ] = KMav). As one of the results it was observed that the chitosan coming from the crab shell is of low molar mass with a value correspondent about 10 times smaller when compared with the standard. The chitosan obtained with the use of electron beam irradiation also shows a decrease in the molar mass as a function of the increase of the absorbed radiation dose.

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  • IPEN-DOC 26956

    GABRIEL, LEANDRO ; MOURA, EDUARDO ; GERALDO, AUREA B.C. . Crystallinity and mechanical properties of recycled, gamma irradiated HDPE/EPDM blends. In: WORLD CHEMISTRY CONGRESS, 46th; ANNUAL MEETING OF THE BRAZILIAN CHEMICAL SOCIETY, 40th; IUPAC GENERAL ASSEMBLY, 49th, July 07-14, 2017, São Paulo, SP. Abstract... Durham, NC, USA: International Union of Pure and Applied Chemistry, 2017.

    Abstract: High Density Polyethylene (HDPE) is a commodity and its wide range of uses comprises several plastic processing in the industry due its conformability, high thermal and chemical resistance and a relative low cost [1]. Also, this material can be recycled many times, which is an important characteristic to decrease the environmental impact when plastic goods reach their end of life. EPDM is one of thermosetting elastomers widely applicated in automotive industry because of its high mechanical, thermal and ageing resistance [2]. The mixture of this both components generate a material with high impact resistance and tensile strength at break [3]. HDPE/EPDM blends are obtained by extrusion of these polymeric components with addition of compatibilizers agents to achieve a homogenous and compatible mixture [4]. In this work the High Density Polyethylene (HDPE) matrix has been recycled four times from original substrate and mixed to non-vulcanized EPDM rubber in proportions from 1 % to 10 % with no addition of compatibilizer agents. The gamma irradiation process was applied at 50 kGy and 100 kGy to both original and recycled blend samples. Characterization of samples was performed by X-ray diffraction and stress-strain assay. These results showed an increase of degree of crystallinity at recycled non-blended HDPE compared to this same parameter to pristine HDPE. It was also observed that crystallinity decreases as EPDM concentration increases. In irradiated samples, this parameter increase with high absorbed doses. The crystallite grain size increases in EPDM concentration from 1 % to 5 %; however, this parameter decreases in blends with 10 % of EPDM contents. This behavior suggests a co-crystallization effect on each polymeric component present in the blend and it may explain the miscibility and compability of both components in this material without addition of other agglutinative substances. The parameter stress at yield is high in pristine HDPE and low in recycled HDPE; this parameter decreases with as EPDM concentration increases in the non-irradiated polymeric blend. In irradiated blends the stress at yield increases in high doses. The irradiation process promotes blend crosslinking, and it is evident in blends with high EPDM concentration where high stress at 100 % strain is observed.

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  • IPEN-DOC 26955

    BEZZAN, OTAVIO P.; PEDROSO, CASSIO C.S.; CARVALHO, JOSE M.; FELINTO, MARIA C.F.C. ; BRITO, HERMI F. ; RODRIGUES, LUCAS C.V.. Discovering new colors of luminescence in rare-earths doped CaTiO3 through co-doping. In: WORLD CHEMISTRY CONGRESS, 46th; ANNUAL MEETING OF THE BRAZILIAN CHEMICAL SOCIETY, 40th; IUPAC GENERAL ASSEMBLY, 49th, July 07-14, 2017, São Paulo, SP. Abstract... Durham, NC, USA: International Union of Pure and Applied Chemistry, 2017.

    Abstract: The luminescence of CaTiO3:Pr3+ has been known since mid-90s [1] and its persistent luminescence has been explained via InterValence Charge Transfer transitions [2]. However, the trivalent dysprosium doped materials besides presenting white luminescence does not present any persistent luminescence. On the other hand, the expected red emission on materials doped with Eu3+ only occur when exciting in the forbidden 4f6-4f6 transitions. The objectives of this work are to show the synthesis and luminescence properties of CaTiO3:Dy3+ and CaTiO3:Dy3+,R3+ prepared with the sol-gel method [3, 4]. The excitation spectra of single Eu3+ or Dy3+ doped materials (Fig. left) show for Eu3+, only the 4f6-4f6 transitions while for Dy3+ both the 4f9-4f9 transitions as well as the O2-→TiIV charge transfer and the host absorption. The excitation spectrum for the Dy3+,Eu3+ co-doped material monitoring the Eu3+ emission at 610 nm exhibit both the Eu3+ intraconfigurational transitions as well as the O2-→TiIV charge transfer and the host absorption. This result indicates that there is no direct energy transfer from Dy3+ to Eu3+, but Dy3+ acts as a sensitizer for Eu3+ to be excited by host transitions. Based on experimental data the energy level diagram was constructed (Fig. right) showing that Eu3+ is deep inside the valence band.

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  • IPEN-DOC 26954

    GONÇALES, LETICIA dos R.; FERRAZ, LUCAS C. de C.; CORREA, OLANDIR V. ; ANTUNES, RENATO A.. Estudo da influência do tamanho de grão sobre o comportamento de corrosão da liga de magnésio AZ91D / Study of grain size influence on the corrosion behavior of AZ91D magnesium alloy. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 71.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALURGICA, DE MATERIAIS E DE MINAS, 16., 26-30 de setembro, 2016, Rio de Janeiro, RJ. Anais... São Paulo, SP: Associação Brasileira de Metalurgia, Materiais e Mineração, 2016. p. 1326-1334.

    Abstract: A liga AZ91D apresenta 9%pAl e 1%pZn e pode ser submetida a tratamento térmico de solubilização seguido de envelhecimento para melhoria de propriedades mecânicas por meio de precipitação da fase beta-Mg17Al12. Esta fase, porém, pode ter efeitos distintos sobre o comportamento de corrosão da liga. Buscando estudar a influência do tamanho de grão da matriz alfa e a presença de precipitados beta sobre a resistência à corrosão da liga AZ91D, este trabalho utilizou lingotes com estrutura bruta de fusão na obtenção de amostras solubilizadas, laminadas a frio e então envelhecidas, para subsequente análise microestrutural e do comportamento de corrosão. A solubilização ocorreu a 445ºC por 24h e foi efetiva em dissolver quase completamente a fase beta. A laminação levou a uma redução de 20% da espessura das amostras e de 400 para 130 μm o tamanho de grão médio, após envelhecimento. O envelhecimento feito a 200ºC em 2 e 24h permitiu a precipitação de fase beta em maior quantidade e melhor distribuição por contornos de grão em relação às amostras fundidas ou solubilizadas. Ensaios de imersão foram realizados, apontando uma leve queda na taxa média de corrosão quando se lamina a amostra, enquanto as amostras solubilizadas (sem fase beta) mostraram maior susceptibilidade à corrosão. Assim, é possível indicar que o refinamento de grãos é benéfico ao formar uma rede de proteção em ligas de magnésio AZ91D, apesar de introduzir defeitos gerados pela laminação.

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  • IPEN-DOC 26953

    GOMES, MAURILIO P. ; SANTOS, IGOR P. dos ; REIS, LUIS A.M. dos ; COUTO, CAMILA P. ; MUCSI, CRISTIANO S. ; COLOSIO, MARCO A.; ROSSI, JESUALDO L. . Characterization of sintered valve seat inserts obtained with AISI M2 high-speed steel after air quenching / Caracterização de insertos para assentos de válvulas sinterizados obtidos com o aço rápido AISI M2 depois de temperados ao ar. In: ABM WEEK; CONGRESSO ANUAL DA ABM, 72.; ENCONTRO NACIONAL DE ESTUDANTES DE ENGENHARIA METALURGICA, DE MATERIAIS E DE MINAS, 17., 02-06 de outubro, 2017, São Paulo, SP. Anais... São Paulo, SP: Associação Brasileira de Metalurgia, Materiais e Mineração, 2017. p. 993-1000.

    Abstract: The aim of this work was to heat treat and characterize sintered valve seat inserts (VSI). The powder metallurgy route was the only way found to substitute cobalt and lead, used in the VSI original alloy, due to their high cost and toxicological effect, respectively. The studied VSI was obtained with AISI M2 high-speed steel powder mixed with iron powder and other additives such as manganese sulphide, graphite, zinc stearate, carbides and copper, which was added by metallic infiltration. All the VSI were air quenched and double tempered, for one hour each, at seven different equidistantly temperatures, ranging from 100 °C up to 700 °C. The physical and mechanical properties were evaluated by means of the VSI apparent density, apparent hardness and crush radial strength. The chemical composition was determined through gas analysis, for the light elements such as carbon and sulfur, and energy dispersive X-ray fluorescence spectrometry for other elements. Microstructural characterization was performed with the support of scanning electron microscopy and energy dispersive spectroscopy. Regarding the VSI final application, the best results were achieved with the inserts air quenched and double tempered at 600 °C.

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  • IPEN-DOC 26952

    GUEDES-SILVA, C.C. ; RODAS, A.C.D.; RIBEIRO, C.; HIGA, O.Z. ; FERREIRA, T.S. . Estudo da bioatividade, adesão e proliferação de osteoblastos em biocompósitos de nitreto de silício. In: CONGRESSO DA SOCIEDADE LATINO AMERICANA DE BIOMATERIAIS, ORGAOS ARTIFICIAIS E ENGENHARIA DE TECIDOS, 14.; EDICAO DO WORKSHOP DE BIOMATERIAIS, ENGENHARIA DE TECIDOS E ORGAOS ARTIFICIAIS, 5., 20-24 de agosto, 2017, Maresias, SP. Abstract... 2017. p. 584-584.

    Abstract: Este estudo avalia o comportamento biológico in vitro de cerâmicas de nitreto de silício denso contendo sílica, cálcia e alumina como constituintes da fase vítrea. Experimentos de bioatividade em SBF e testes de adesão e proliferação de celular com células MG-63 foram realizados nas superfícies das amostras. Os resultados mostraram que os materiais estudados formaram uma camada de apatita na superfície após 16 dias de imersão em SBF e que são capazes de promover a proliferação de osteoblastos e formação de matriz calcificada in vitro, demonstrando seu potencial para aplicações como dispositivos protéticos.

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A pesquisa no RD utiliza os recursos de busca da maioria das bases de dados. No entanto algumas dicas podem auxiliar para obter um resultado mais pertinente.

É possível efetuar a busca de um autor ou um termo em todo o RD, por meio do Buscar no Repositório , isto é, o termo solicitado será localizado em qualquer campo do RD. No entanto esse tipo de pesquisa não é recomendada a não ser que se deseje um resultado amplo e generalizado.

A pesquisa apresentará melhor resultado selecionando um dos filtros disponíveis em Navegar

Os filtros disponíveis em Navegar tais como: Coleções, Ano de publicação, Títulos, Assuntos, Autores, Revista, Tipo de publicação são autoexplicativos. O filtro, Autores IPEN apresenta uma relação com os autores vinculados ao IPEN; o ID Autor IPEN diz respeito ao número único de identificação de cada autor constante no RD e sob o qual estão agrupados todos os seus trabalhos independente das variáveis do seu nome; Tipo de acesso diz respeito à acessibilidade do documento, isto é , sujeito as leis de direitos autorais, ID RT apresenta a relação dos relatórios técnicos, restritos para consulta das comunidades indicadas.

A opção Busca avançada utiliza os conectores da lógica boleana, é o melhor recurso para combinar chaves de busca e obter documentos relevantes à sua pesquisa, utilize os filtros apresentados na caixa de seleção para refinar o resultado de busca. Pode-se adicionar vários filtros a uma mesma busca.

Exemplo:

Buscar os artigos apresentados em um evento internacional de 2015, sobre loss of coolant, do autor Maprelian.

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

Para indexação dos documentos é utilizado o Thesaurus do INIS, especializado na área nuclear e utilizado em todos os países membros da International Atomic Energy Agency – IAEA , por esse motivo, utilize os termos de busca de assunto em inglês; isto não exclui a busca livre por palavras, apenas o resultado pode não ser tão relevante ou pertinente.

95% do RD apresenta o texto completo do documento com livre acesso, para aqueles que apresentam o significa que e o documento está sujeito as leis de direitos autorais, solicita-se nesses casos contatar a Biblioteca do IPEN, bibl@ipen.br .

Ao efetuar a busca por um autor o RD apresentará uma relação de todos os trabalhos depositados no RD. No lado direito da tela são apresentados os coautores com o número de trabalhos produzidos em conjunto bem como os assuntos abordados e os respectivos anos de publicação agrupados.

O RD disponibiliza um quadro estatístico de produtividade, onde é possível visualizar o número dos trabalhos agrupados por tipo de coleção, a medida que estão sendo depositados no RD.

Na página inicial nas referências são sinalizados todos os autores IPEN, ao clicar nesse símbolo será aberta uma nova página correspondente à aquele autor – trata-se da página do pesquisador.

Na página do pesquisador, é possível verificar, as variações do nome, a relação de todos os trabalhos com texto completo bem como um quadro resumo numérico; há links para o Currículo Lattes e o Google Acadêmico ( quando esse for informado).

ATENÇÃO!

ESTE TEXTO "AJUDA" ESTÁ SUJEITO A ATUALIZAÇÕES CONSTANTES, A MEDIDA QUE NOVAS FUNCIONALIDADES E RECURSOS DE BUSCA FOREM SENDO DESENVOLVIDOS PELAS EQUIPES DA BIBLIOTECA E DA INFORMÁTICA.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.