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  • IPEN-DOC 25194

    METAIRON, SABRINA ; ZAMBONI, CIBELE B. ; SUZUKI, MIRIAM F. ; BUENO, CARLOS R.. Evaluation of ions and metals in the blood of GRMD dogs submitted to hASCs therapy by NAA and XRF techniques. Applied Radiation and Isotopes, v. 143, p. 107-112, 2019. DOI: 10.1016/j.apradiso.2018.10.024

    Abstract: The elements Br, Ca, Cl, Cr, Fe, K, Mg, Na, P, Rb, S, and Zn were investigated in the whole blood samples of Golden Retriever dogs submitted to cell therapy (hASCs). These analyses were performed over 2 years using Neutron Activation Analysis and X-Ray Fluorescence techniques. The results were compared with control and untreated dog's. A significant increase was observed in K blood levels. There was also variation in blood levels of Br, Cr, Fe, Rb, S, and Zn.


  • IPEN-DOC 25193

    FURIGO, ISADORA C.; SUZUKI, MIRIAM F. ; OLIVEIRA, JOAO E. ; RAMOS-LOBO, ANGELA M.; TEIXEIRA, PRYSCILA D.S.; PEDROSO, JOAO A.; ALENCAR, AMANDA de; ZAMPIERI, THAIS T.; BUONFIGLIO, DANIELLA C.; QUARESMA, PAULA G.F.; PRADA, PATRICIA O.; BARTOLINI, PAOLO ; SOARES, CARLOS R.J. ; DONATO JUNIOR, JOSE. Suppression of prolactin secretion partially explains the antidiabetic effect of bromocriptine in ob/ob mice. Endocrinology, v. 160, n. 1, p. 193-204, 2019. DOI: 10.1210/en.2018-00629

    Abstract: Previous studies have shown that bromocriptine mesylate (Bromo) lowers blood glucose levels in adults with type 2 diabetes mellitus; however, the mechanism of action of the antidiabetic effects of Bromo is unclear. As a dopamine receptor agonist, Bromo can alter brain dopamine activity affecting glucose control, but it also suppresses prolactin (Prl) secretion, and Prl levels modulate glucose homeostasis. Thus, the objective of the current study was to investigate whether Bromo improves insulin sensitivity via inhibition of Prl secretion. Male and female ob/ob animals (a mouse model of obesity and insulin resistance) were treated with Bromo and/or Prl. Bromo-treated ob/ob mice exhibited lower serum Prl concentration, improved glucose and insulin tolerance, and increased insulin sensitivity in the liver and skeletal muscle compared with vehicle-treated mice. Prl replacement in Bromo-treated mice normalized serum Prl concentration without inducing hyperprolactinemia. Importantly, Prl replacement partially reversed the improvements in glucose homeostasis caused by Bromo treatment. The effects of the Prl receptor antagonist G129R-hPrl on glucose homeostasis were also investigated. We found that central G129R-hPrl infusion increased insulin tolerance of male ob/ob mice. In summary, our findings indicate that part of Bromo effects on glucose homeostasis are associated with decrease in serum Prl levels. Because G129R-hPrl treatment also improved the insulin sensitivity of ob/ob mice, pharmacological compounds that inhibit Prl signaling may represent a promising therapeutic approach to control blood glucose levels in individuals with insulin resistance.


  • IPEN-DOC 25192

    GOTARDELO, DANIEL R. ; COURROL, LILIA C.; BELLINI, MARIA H. ; SILVA, FLAVIA R. de O. ; SOARES, CARLOS R.J. . Porphyrins are increased in the faeces of patients with prostate cancer: a casecontrol study. BMC Cancer, v. 18, n. 1090, 2018. DOI: 10.1186/s12885-018-5030-1

    Abstract: Background: Experimental models of prostate cancer have demonstrated increased levels of protoporphyrin IX (PpIX) in the blood and faeces of mice. Hence, the quantification of these autofluorescent molecules could be hypothesized to be a potential marker for this type of tumour. In this case-control study, the autofluorescence of porphyrins in human faeces from patients with prostate cancer and control subjects was analysed using fluorescence spectroscopy. Methods: First, 3 mL of analytical-grade acetone was added to 0.3 g of faeces, and the mixture was macerated and centrifuged at 4000 rpm for 15 min. The supernatant was analysed spectroscopically. The emission spectra from 550 to 750 nm were obtained by exciting the samples at 405 nm. Results: A significant difference between the samples from control and cancer subjects was established in the spectral region of 670–675 nm (p = 0.000127), which corresponds to a significant increase in faecal porphyrins in patients with cancer. There was no statistically significant correlation between PSA levels and faecal porphyrins. Conclusion: In this preliminary study conducted in humans, the results show a simple and non-invasive method to assess faecal porphyrins, which have the potential to function as a tumour biomarker in patients with prostate cancer. This approach has improved sensitivity and specificity over PSA testing. Additional prospective studies with larger sample sizes are required to validate these findings.


  • IPEN-DOC 25191

    SILVA, CLEIDE M.R. da ; CHURA-CHAMBI, ROSA M. ; PEREIRA, LENNON R.; CORDEIRO, YRAIMA; FERREIRA, LUIS C. de S.; MORGANTI, LIGIA . Association of high pressure and alkaline condition for solubilization of inclusion bodies and refolding of the NS1 protein from zika virus. BMC Biotechnology, v. 18, n. 78, 2018. DOI: 10.1186/s12896-018-0486-2

    Abstract: Background: Proteins in inclusion bodies (IBs) present native-like secondary structures. However, chaotropic agents at denaturing concentrations, which are widely used for IB solubilization and subsequent refolding, unfold these secondary structures. Removal of the chaotropes frequently causes reaggregation and poor recovery of bioactive proteins. High hydrostatic pressure (HHP) and alkaline pH are two conditions that, in the presence of low level of chaotropes, have been described as non-denaturing solubilization agents. In the present study we evaluated the strategy of combination of HHP and alkaline pH on the solubilization of IB using as a model an antigenic form of the zika virus (ZIKV) non-structural 1 (NS1) protein. Results: Pressure-treatment (2.4 kbar) of NS1-IBs at a pH of 11.0 induced a low degree of NS1 unfolding and led to solubilization of the IBs, mainly into monomers. After dialysis at pH 8.5, NS1 was refolded and formed soluble oligomers. High (up to 68 mg/liter) NS1 concentrations were obtained by solubilization of NS1-IBs at pH 11 in the presence of arginine (Arg) with a final yield of approximately 80% of total protein content. The process proved to be efficient, quick and did not require further purification steps. Refolded NS1 preserved biological features regarding reactivity with antigen-specific antibodies, including sera of ZIKV-infected patients. The method resulted in an increase of approximately 30-fold over conventional IB solubilization-refolding methods. Conclusions: The present results represent an innovative non-denaturing protein refolding process by means of the concomitant use of HHP and alkaline pH. Application of the reported method allowed the recovery of ZIKV NS1 at a condition that maintained the antigenic properties of the protein.


  • IPEN-DOC 25190

    MUCCILLO, REGINALDO ; FLORIO, DANIEL Z. de; MUCCILLO, ELIANA N.S. . Equimolar yttria-stabilized zirconia and samaria-doped ceria solid solutions. Ceramics, v. 1, n. 2, p. 343-352, 2018. DOI: 10.3390/ceramics1020027

    Abstract: Compositions of (ZrO2)0.92(Y2O3)0.08 (zirconia: 8 mol % yttria—8YSZ) and (CeO2)0.8(Sm2O3)0.2 (ceria: 20 mol % samaria—SDC20) ceramic powders were prepared by attrition milling to form an equimolar powder mixture, followed by uniaxial and isostatic pressing. The pellets were quenched to room temperature from 1200 °C, 1300 °C, 1400 °C and 1500 °C to freeze the defects configuration attained at those temperatures. X-ray diffraction analyses, performed in all quenched pellets, show the evolution of the two (8YSZ and SDC20) cubic fluorite structural phases to a single phase at 1500 °C, identified by Rietveld analysis as a tetragonal phase. Impedance spectroscopy analyses were carried out in pellets either quenched or slowly cooled from 1500 °C. Heating the quenched pellets to 1000 °C decreases the electrical resistivity while it increases in the slowly cooled pellets; the decrease is ascribed to annealing of defects created by lattice micro-tensions during quenching while the increase to partial destabilization of the tetragonal phase.


  • IPEN-DOC 25189

    BUSTILLOS, OSCAR V. . A fonte de íons por impacto de elétrons na espectrometria de massas. Revista Analytica, v. 16, n. 97, p. 38-39, 2018.


  • IPEN-DOC 25155

    SILVA, ANDERSON G.M. da; BATALHA, DANIEL C.; RODRIGUES, THENNER S. ; CANDIDO, EDUARDO G.; LUZ, SULUSMON C.; FREITAS, ISABEL C. de; FONSECA, FABIO C. ; OLIVEIRA, DANIELA C. de; TAYLOR, JASON G.; TORRESI, SUSANA I.C. de; CAMARGO, PEDRO H.C.; FAJARDO, HUMBERTO V.. Sub-15 nm CeO2 nanowires as an efficient nonnoble metal catalyst in the room-temperature oxidation of aniline. Catalysis Science and Technology, v. 8, n. 7, p. 1828-1839, 2018. DOI: 10.1039/c7cy02402a

    Abstract: We described herein the facile synthesis of sub-15 nm CeO2 nanowires based on a hydrothermal method without the use of any capping/stabilizing agent, in which an oriented attachment mechanism took place during the CeO2 nanowire formation. The synthesis of sub-15 nm CeO2 nanowires could be achieved on relatively large scales (∼2.6 grams of nanowires per batch), in high yields (>94%), and at low cost. To date, there are only a limited number of successful attempts towards the synthesis of CeO2 nanowires with such small diameters, and the reported protocols are typically limited to low amounts. The nanowires displayed uniform shapes and sizes, high surface areas, an increased number of oxygen defects sites, and a high proportion of Ce3+/Ce4+ surface species. These features make them promising candidates for oxidation reactions. To this end, we employed the selective oxidation of aniline as a model transformation. The sub-15 nm CeO2 nanowires catalyzed the selective synthesis of nitrosobenzene (up to 98% selectivity) from aniline at room temperature using H2O2 as the oxidant. The effect of solvent and temperature during the catalytic reaction was investigated. We found that such parameters played an important role in the control of the selectivity. The improved catalytic activities observed for the sub-15 nm nanowires could be explained by: i) the uniform morphology with a typical dimension of 11 ± 2 nm in width, which provides higher specific surface areas relative to those of conventional catalysts; ii) the significant concentration of oxygen vacancies and high proportion of Ce3+/Ce4+ species at the surface that represent highly active sites towards oxidation reactions; iii) the crystal growth along the (110) highly catalytically active crystallographic directions, and iv) the mesoporous surface which is easily accessible by liquid substrates. The results reported herein demonstrated high activities under ambient conditions, provided novel insights into selectivities, and may inspire novel metal oxide-based catalysts with desired performances.


  • IPEN-DOC 25154

    BARABAS, ROBERTA de C. ; LIMA, ANA C. de S. ; SABUNDJIAN, GAIANE . A panoramic view of nuclear science and technology education worldwide. International Journal of Development Research, v. 8, n. 10, p. 23256-23259, 2018.

    Abstract: Nuclear energy has been used as a source of clean energy with many benefits. Nevertheless, it is still addressed with prejudice. The atomic bombing of Hiroshima and Nagasaki during World War II (1945), the Three Mile Island accident (1979), Chernobyl accident (1986), the crash of the cesium-137 in Goiânia, Brazil (1987), and the accident in Fukushima (2011) may have been responsible for the negative image of nuclear energy. Researches on education have been conducted with students concerning the conceptual and practical issues of nuclear energy. This work aims to review the literature about nuclear energy education around the world in both, elementary school and high school. Since most educational researches on nuclear energy were published after 1980, this literature review covered the researches that have been published since 1980. The data were presented in chronological order. The results from the literature review provided a clear visualization of the global nuclear energy educational scenario, showing that the theme is still addressed with prejudice due to an incorrect view of nuclear energy and a limited view of its benefits. Concerning the science textbooks, the literature reports that the theme should be better addressed, encouraging students to research more about it. The data from this literature review will serve as a reference for a future proposal for a teaching training program for Brazilian science/physics high school teachers using a new teaching approach.


  • IPEN-DOC 25153

    BORGES, EDUARDO M. ; SABUNDJIAN, GAIANE ; DAURIA, FRANCESCO; PETRUZZI, ALESSANDRO. Uncertainty calculation in small break LOCA in the emergency core cooling system connected to the hot leg of Angra 2 nuclear power plant. International Journal of Nuclear Energy Science and Technology, v. 12, n. 2, p. 139-160, 2018.

    Abstract: Owing to the occurrence of nuclear accidents, worldwide nuclear regulatory organisations included the analysis of accidents considered as design basis accidents – Loss of Coolant Accident (large and small-break, LBLOCA or SBLOCA) – in the safety analysis reports of nuclear facilities. In Brazil, the tool selected by the licensing authority, Comissão Nacional de Energia Nuclear (CNEN), is RELAP5 Code. The aim of this paper is the evaluation of the performance of the Emergency Core Cooling System (ECCS) of Angra 2 nuclear reactor during SBLOCA. In this study, the RELAP5 code and the Code Internal Assessment of Uncertainty (CIAU) were used to simulate and analyse the uncertainties of the results. The postulated accident is the SBLOCA in the hot leg connected to the ECCS described in the Final Safety Analysis Report of Angra 2 (FSAR/A2). The results from this study were satisfactory when compared with the FSAR/A2.


  • IPEN-DOC 25152

    BAPTISTA FILHO, B.D. ; CABRAL, E.L.L. ; BARROSO, A.C.O. . An R-package for water and steam properties for scientific and general use. International Journal of Nuclear Energy Science and Technology, v. 12, n. 2, p. 172-195, 2018.

    Abstract: The International Association for the Properties of Water and Steam (IAPWS) develops formulations for the calculation of thermophysical properties of water as a function of different combinations of temperature, density, pressure, enthalpy, and entropy. These properties are useful for scientists and nuclear, chemical, and mechanical engineers who analyse experimental data or are involved with projects and equipment development, like heat exchangers, turbines, or nuclear power reactors. The IAPWS-95 formulation solves the fundamental equation of Helmholtz free energy as a function of temperature and density. This paper gives a description of how these equations are solved and exemplifies the use of a package developed for the free platform R. The IAPWS95 package was developed to help users to get access to the IAPWS-95 formulation in a free software environment which is growing exponentially. Transport properties were programmed using other IAPWS releases. The examples consider the uncertainty analysis of thermal parameters of a nuclear power reactor and the preparation of tables and graphs of water properties.


  • IPEN-DOC 25151

    ICHIKAWA, RODRIGO U. ; PARRA, JOAO P.R.L.L.; MARTINS, MURILLO L.; YOSHITO, WALTER K. ; SAEKI, MARGARIDA J.; TURRILLAS, XAVIER; MARTINEZ, LUIS G. . Size-strain analysis of iron-excess Mn–Zn ferrite nanoparticles using synchrotron diffraction and its correlation with magnetic saturation and isoelectric pH. Journal of Nanoscience and Nanotechnology, v. 18, n. 8, p. 5697-5703, 2018. DOI: 10.1166/jnn.2018.15446

    Abstract: Iron-excess Mn–Zn ferrite nanoparticles were prepared by coprecipitation with sodium hydroxide (NaOH) at different concentrations (0.1, 0.2, 0.5 and 1.0 mol/L). The results of X-ray diffraction (XRD) analysis using Whole Powder Pattern Modeling (WPPM) showed that higher concentrations of NaOH promote crystallite growth and broader dispersion in crystallite sizes. Energy dispersive X-ray spectroscopy indicates that zinc loss is noticeable when [NaOH] ≥ 0.2 mol/L. XRD revealed also a significant less-crystalline phase contribution alongside the main peaks of the nanocrystalline cubic spinel ferrite phase. The less-crystalline fraction is lower for the ferrite obtained with 0.2 mol/L of NaOH, being about 50% and more than 70% for the other samples. Despite of the less-crystalline fraction and the excess of iron, no secondary phases were detected. The Warren curves showed that the concentration of NaOH significantly influences the microstrain in the crystallites, being smaller for the sample obtained with NaOH at 0.2 mol/L. The sample prepared with this condition presented the better properties to be used as magnetic tracer in clinical diagnoses combining small mean crystallite size, low microstrain, which resulted in materials with higher magnetic saturation and high surface charge under blood pH.


  • IPEN-DOC 25111

    CUNICO, PATRICIA ; KUMAR, ANU; ALCANTARA, RAQUEL R. ; FUNGARO, DENISE A. . Adsorption of solophenyl dyes from aqueous solution by modified nanozeolite from bottom ash and its toxicity to C. dubia. Current Nanomaterials, v. 2, n. 2, p. 95-103, 2017. DOI: 10.2174/2405461503666180201152351

    Abstract: Background: It is known that wastewater from textile industries are responsible for producing large amounts of highly contaminated effluents by various types of synthetic dyes. These compounds can be toxic, and in some cases, are carcinogenic and mutagenic and its removal is recommended. Application: In the area of water purification, nanomaterials have been applied for removal of several compounds. Of the four classes of nanomaterials, zeolites have demonstrated good results for the removal of dyes. Nanozeolite synthesized from bottom ash and modified with hexadecyltrimethylamonium (ZMB) was used as adsorbent to removal of Solophenyl Navy (SN), Solophenyl Turquoise (ST) and their hydrolyzed forms (SNH and STH, respectively) from simulated textile wastewater. Method: The physical-chemical characterization of materials was presented by using relevant analytical methods (XRD, SEM, BET surface area, etc.). Effects of parameters such as initial dye concentration, contact time and equilibrium adsorption were evaluated. The adsorption kinetics followed the pseudo-second-order model. Results: Langmuir isotherm model shows the best fit for most dyes-ZMB systems. In order to identify if ZMB presented toxicity for the environment, bioassay and toxicity identification evaluation (TIE) with C. dubia were performed. The leached of ZMB was toxic to daphinids (11.3 TU). Conclusion: TIE results appointed that the main cause of the toxicity could be due the surfactant and metal ions presents in aqueous solution.


  • IPEN-DOC 25149

    WETTER, NIKLAUS U. ; MIRANDA, ADRIANA R. de ; PECORARO, EDISON; RIBEIRO, SIDNEY J.L.; JIMENEZ-VILLAR, ERNESTO . Dynamic random lasing in silica aerogel doped with rhodamine 6G. RSC Advances, v. 8, n. 52, p. 29678-29685, 2018. DOI: 10.1039/c8ra04561e

    Abstract: Silica aerogel is a lightweight material, well known for its good mechanical and thermal characteristics, but its optical properties have received less attention, because it is weakly scattering. Here we present for the first time the lasing properties and their complex dynamics of silica aerogel doped with R6G. It is shown that the Q factors of the lasing modes determine the operation of the laser, being either resonant or ASE-lasing. For resonant lasing, the number of resonators is easily varied and the number of modes in a single resonator and their emission frequency can be dynamically adjusted, making this a truly versatile photonics material.


  • IPEN-DOC 25148

    WANG, JAMES S.; KAWA, S.R.; COLLATZ, G.J.; SASAKAWA, MOTOKI; GATTI, LUCIANA V. ; MACHIDA, TOSHINOBU; LIU, YUPING; MANYIN, MICHAEL E.. A global synthesis inversion analysis of recent variability in CO2 fluxes using GOSAT and in situ observations. Atmospheric Chemistry and Physics, v. 18, n. 15, p. 11097-11124, 2018. DOI: 10.5194/acp-18-11097-2018

    Abstract: The precise contribution of the two major sinks for anthropogenic CO2 emissions, terrestrial vegetation and the ocean, and their location and year-to-year variability are not well understood. Top-down estimates of the spatiotemporal variations in emissions and uptake of CO2 are expected to benefit from the increasing measurement density brought by recent in situ and remote CO2 observations.We uniquely apply a batch Bayesian synthesis inversion at relatively high resolution to in situ surface observations and bias-corrected GOSAT satellite column CO2 retrievals to deduce the global distributions of natural CO2 fluxes during 2009–2010. The GOSAT inversion is generally better constrained than the in situ inversion, with smaller posterior regional flux uncertainties and correlations, because of greater spatial coverage, except over North America and northern and southern high-latitude oceans. Complementarity of the in situ and GOSAT data enhances uncertainty reductions in a joint inversion; however, remaining coverage gaps, including those associated with spatial and temporal sampling biases in the passive satellite measurements, still limit the ability to accurately resolve fluxes down to the sub-continental or subocean basin scale. The GOSAT inversion produces a shift in the global CO2 sink from the tropics to the north and south relative to the prior, and an increased source in the tropics of 2 PgC yr􀀀1 relative to the in situ inversion, similar to what is seen in studies using other inversion approaches. This result may be driven by sampling and residual retrieval biases in the GOSAT data, as suggested by significant discrepancies between posterior CO2 distributions and surface in situ and HIPPO mission aircraft data. While the shift in the global sink appears to be a robust feature of the inversions, the partitioning of the sink between land and ocean in the inversions using either in situ or GOSAT data is found to be sensitive to prior uncertainties because of negative correlations in the flux errors. The GOSAT inversion indicates significantly less CO2 uptake in the summer of 2010 than in 2009 across northern regions, consistent with the impact of observed severe heat waves and drought. However, observations from an in situ network in Siberia imply that the GOSAT inversion exaggerates the 2010–2009 difference in uptake in that region, while the prior CASA-GFED model of net ecosystem production and fire emissions reasonably estimates that quantity. The prior, in situ posterior, and GOSAT posterior all indicate greater uptake over North America in spring to early summer of 2010 than in 2009, consistent with wetter conditions. The GOSAT inversion does not show the expected impact on fluxes of a 2010 drought in the Amazon; evaluation of posterior mole fractions against local aircraft profiles suggests that time-varying GOSAT coverage can bias the estimation of interannual flux variability in this region.


  • IPEN-DOC 25147

    VINAGRE, CARMEN G.; FREITAS, FATIMA R.; MESQUITA, CARLOS H. de ; VINAGRE, JULIANA C.; MARIANI, ANA C.; KALIL-FILHO, ROBERTO; MARANHAO, RAUL C.. Removal of chylomicron remnants from the bloodstream is delayed in aged subjects. Aging and Disease, v. 9, n. 4, p. 748-754, 2018. DOI: 10.14336/AD.2017.1003

    Abstract: Dietary fats absorbed in the intestine are transported in the circulation as chylomicrons and remnants that have atherogenic potential. Although postprandial lipidemia is increased in older subjects, the specific chylomicron metabolism has not been explored in older subjects nor compared to young subjects, which is the focus of this study. After a 12 h fast, artificially-made emulsions similar to lymph chylomicrons and doubly labeled with radioactive cholesteryl esters and triglycerides were intravenously injected in 23 older (66±4 years) and 20 young (24±3 years) subjects. Sequential blood samples were collected to determine fractional clearance rates (FCR, in min-1) by compartmental analysis. Older subjects had higher LDL-cholesterol (p<0.001) and triglycerides (p<0.0001) than young subjects; HDL-cholesterol presented no difference. The emulsion cholesteryl-ester FCR was lower in older subjects compared to the young (p=0.0001). The emulsion triglyceride FCR did not differ in the two groups. Tested in vitro, however, the lipolysis of the emulsion triglycerides was less intense in the older than in the young subjects. As delayed removal of remnants, indicated by the pronouncedly smaller cholesteryl ester FCR, is related to the presence of cardiovascular diseases, this can be a risk factor which could accelerate atherogenic complications occurring in aged subjects


  • IPEN-DOC 25146

    VILLEGAS, GETHZEMANI M.E.; MORSELLI, GIOVANNI R. ; GONZALEZ-PEREZ, GIOVANNI ; LUGAO, ADEMAR B. . Enhancement swelling properties of PVGA hydrogel by alternative radiation crosslinking route. Radiation Physics and Chemistry, v. 153, p. 44-50, 2018. DOI: 10.1016/j.radphyschem.2018.08.038

    Abstract: The development of environmentally friendly materials based on non-toxic absorbent polymers, which can ensure high water absorption for several applications in biomedical or agricultural areas, is one of the most complexes problems. In the literature, the non-toxic biodegradable polymer poly(vinyl alcohol) (PVA) was chemically modified with glyoxylic acid to obtain poly(vinylglyoxylic acid) (PVGA) as a biodegradable superabsorbent hydrogel polymer (SHAP), but in fact, the chemical crosslinking reaction decreases the water absorption capacity. In order to crosslink PVGA without losing its absorbent capacity; an alternative radiationcrosslink route has been studied. Radiation-induced crosslinking in the main C-C chain of PVGA where not all free hydrophilic groups (COOH) are involved in a crosslinking reaction as occurs in a traditional chemical reaction. The aim of this work was not only the chemical modification of 99% hydrolyzed PVA to obtain the linear and non-crosslinked PVGA at certain conditions, but also radiation crosslinking at different doses, at dose rate of 5 kGy h−1 attempting to increase the superabsorbent capacity. The samples were characterized by Scanning Electron Microscopy (SEM), Thermo-gravimetrical Analysis (TGA), Nuclear Magnetic Resonance (1H) (NMR) and Infrared Spectroscopy (FTIR). The swelling behavior was measured gravimetrically in different solvents as pure water, buffer pH 3, 7 and 10. Results showed that radiation-crosslink route improves the swelling behavior of PVGA in approximately 215% when compared with PVGA chemically crosslinked, swelled in pure water.


  • IPEN-DOC 25145

    VARA-VELA, ANGEL; ANDRADE, MARIA de F.; ZHANG, YANG; KUMAR, PRASHANT; YNOUE, RITA Y.; SOUTO-OLIVEIRA, CARLOS E.; LOPES, FABIO J. da S. ; LANDULFO, EDUARDO . Modeling of atmospheric aerosol properties in the São Paulo metropolitan area: impact of biomass burning. Journal of Geophysical Research: Atmospheres, v. 123, n. 17, p. 9935-9956, 2018. DOI: 10.1029/2018JD028768

    Abstract: Smoke particles ejected into the atmosphere from biomass burning can modify the atmospheric composition around and even far from the sources. In late winter and early spring, biomass burning emissions from inland regions can be efficiently transported to urban areas in southeastern South America, thus affecting air quality in those areas. In this study, the Weather Research and Forecasting with Chemistry model was applied in order to investigate the impact of biomass burning sources on aerosol loadings and properties over the São Paulo Metropolitan Area (SPMA), in southeastern Brazil, during the period from 19 August to 3 September 2014. The model performance was evaluated using available aerosol measurements from the Narrowing the Uncertainties on Aerosol and Climate Change in São Paulo State project. The combined application of aerosol data and Weather Research and Forecasting with Chemistry simulations made it possible to represent some of the most important aerosol properties, such as particle number concentration and cloud condensation nuclei activation, in addition to evaluation of the impact of biomass burning by analyzing a 5‐day transport event, from 22 to 26 August 2014. During this transport event, differences in the average predicted PM2.5 concentration reached 15 μg/m3 (peaking at 20 μg/m3 during the nighttime hours) over the SPMA, compared with 35 μg/m3 over inland areas northwest and north of the SPMA. Biomass burning accounted for up to 20% of the baseline particle number concentration‐ and cloud condensation nuclei‐weighted relative differences over the SPMA (2,300 and 1,400 cm−3, respectively).


  • IPEN-DOC 25144

    TOMINAGA, FLAVIO K. ; BATISTA, ANA P. dos S.; TEIXEIRA, ANTONIO C.S.C.; BORRELY, SUELI I. . Degradation of diclofenac by electron beam irradiaton: Toxicitiy removal, by-products identification and effect of another pharmaceutical compound. Journal of Environmental Chemical Engineering, v. 6, n. 4, p. 4605-4611, 2018. DOI: 10.1016/j.jece.2018.06.065

    Abstract: Water contamination by the anti-inflammatory drug diclofenac (DCF) is a consequence of its incomplete removal in wastewater and sewage treatment plants, which is potentialized by interactions with other pharmaceutical contaminants. In this context, electron beam irradiation (EBI) has been considered a clean technology for degrading pharmaceutical compounds in water. Nevertheless, the identification of DCF by-products and their correlation with biological recalcitrance and acute toxicity are poorly understood. In this study, the V. fischeri test was used to characterize DCF toxicity in the absence and presence of fluoxetine (FLX), prior and after irradiation. The results showed complete DCF degradation at low dose (5 kGy). DCF concentration followed pseudo first-order decay with respect to the absorbed, with k0 = (1.33 ± 0.10) kGy−1 (DCF) and k0 = (0.90 ± 0.12) kGy−1 (DCF+FLX). In contrast, negligible TOC removal was observed even at 7.5 kGy, with the formation of recalcitrant, non-biodegradable by-products, as also suggested by the respirometry test. Despite that, the toxicity of the DCF solution diminished from (19.6 ± 1.6) TU to (6.2 ± 2.3) TU, and from (6.8 ± 0.9) TU to (3.1 ± 0.2) TU, in the absence and presence of FLX, respectively, after irradiation up to 5 kGy. Four of the eleven by-products identified by direct-injection MS were easily degraded by EBI, and one (C13H14ClNO5) was considered the least recalcitrant but the most toxic. Based on these results, a possible DCF degradation pathway is proposed, involving hydroxylation and oxidation of aromatic rings, dehalogenation and C−N bond cleavage.


  • IPEN-DOC 25143

    SOUZA, J.P. ; GROSSO, R.L. ; MUCCILLO, R. ; MUCCILLO, E.N.S. . Phase composition and ionic conductivity of zirconia stabilized with scandia and europia. Materials Letters, v. 229, p. 53-56, 2018. DOI: 10.1016/j.matlet.2018.06.091

    Abstract: Sintered specimens of zirconia-10 mol% scandia pure and codoped (up to 1.25 mol%) with europium sexquioxide were prepared by solid-state synthesis, aiming to stabilize at room temperature the high-conductivity cubic phase. High-temperature X-ray diffraction and differential scanning calorimetry results reveal that small amounts of the codopant reduce the enthalpy of phase transition, and full stabilization is evidenced for 1 mol% europium sexquioxide. The low-temperature (<600 C) ionic conductivity increases with increasing codopant content.


  • IPEN-DOC 25142

    SOARES, EDSON P. ; CASINI, JULIO C.S.; VIEIRA, LIGIA S.; SILVA, FRANKS M.; FARIA, RUBENS N. de ; TAKIISHI, HIDETOSHI . Effect of hydrogen decrepitation pressure on the particle size of rare earth based alloys for Ni-MH battery production. Materials Science Forum, v. 930, p. 637-642, 2018. DOI: 10.4028/

    Abstract: This paper presents the results obtained from the hydrogenation and decrepitation of three LaNi-based alloys, La0.7Mg0.3Al0.3Mn0.4Co0.5Ni3.8, La0.7Mg0.3Al0.3Mn0.4Cu0.5Ni3.8 and La0.7Mg0.3Al0.3Mn0.4Sn0.5Ni3.8, in the as-cast condition. The procedure for decrepitating the alloys to be used in the negative electrode of the batteries was carried out using a combination of various hydrogen pressures (2-9 bar) at room temperature. At 2 bar of H2 it was revealed that Co, Cu and Sn have influence on the microstructures of the hydrogenated alloys and on the efficiency of hydrogen decrepitation. None of these alloys required thermal heating to activate and start the hydrogen absorption process. The decrepitated materials were characterized by scanning electron microscopy (SEM). The electrochemical measurements were performed using the tested negative electrode between two Ni(OH)2 electrodes as a battery cell.


  • IPEN-DOC 25141

    SILVA, FLAVIA R.O. ; YOSHITO, WALTER K. ; COSENTINO, IVANA C. ; BRESSIANI, ANA H.A. ; LIMA, NELSON B. . Synthesis and characterization of novel crystalline mesoporous beta-tricalcium phosphate nanoparticles. Materials Science Forum, v. 930, p. 63-66, 2018. DOI: 10.4028/

    Abstract: A nano-sized magnesium substituted beta-tricalcium phosphate (Mg:β-TCP) was synthesized by an aqueous precipitation method, at room temperature, in one single step. In the present study, the novel and stable Mg:β-TCP resulted in a crystalline and spherical nanoparticles (diameter of approximately 20 nm) with mesoporous structures and a high specific surface area (about 574 m2/g). These special characteristics make this novel crystalline mesoporous Mg: β-TCP nanoparticles ideal candidates for drug delivery system and a promising non-viral vector for gene therapy.


  • IPEN-DOC 25140

    SILVA, RODRIGO P. da; TUDELA, DIEGO R.G.; MUNITA, CASIMIRO S. ; HAZENFRATZ, ROBERTO ; TATUMI, SONIA H.; YEE, MARCIO; MITTANI, JUAN C.R.. Firing temperature determination and thermoluminescence dating of a brick with cuneiform characters found in the ruins of Ancient Babylon / Determinação da temperatura de queima e datação por termoluminescência de um tijolo com caracteres cuneiformes encontrado nas ruínas da antiga Babilônia. Revista do Museu de Arqueologia e Etnologia, n. 28, p. 58-69, 2017. DOI: 10.11606/issn.2448-1750.revmae.2017.133911

    Abstract: This paper aims to study a brick with inscriptions in cuneiform characters in which the sentences are almost complete. Typological studies in agreement with historical records suggest that the tablet was manufactured in the 6th century BCE during the dynasty of Nebuchadnezzar II, Great King of Babylon. The sample was studied by X-ray diffraction analysis (XRD), electron paramagnetic resonance (EPR), thermoluminescence (TL), and instrumental neutron activation analysis (INAA) techniques. The results showed that the brick is 2350 years old (± 40) and its firing temperature was lower than 400 °C.


  • IPEN-DOC 25139

    SILVA, DANILO L.C. e ; KASSAB, LUCIANA R.P.; SANTOS, ANTONIO D. dos ; PILLIS, MARINA F.. Evaluation of carbon thin films using raman spectroscopy. Materials Research, v. 21, n. 4, 2018. DOI: 10.1590/1980-5373-MR-2017-0787

    Abstract: Carbon thin films deposited by the magnetron sputtering technique were evaluated by Raman spectroscopy to study the influence on their crystallinity caused by different parameters like the carbon deposition time, the different buffer-layers and substrates employed and also two distinct heat treatments. The present results showed that the choice of these parameters plays an important role in the production of these films. The results also indicate the possibility of using the technique for the production of carbon thin films to be employed in future in applications with controlled content of structural defects, predominance of ordered sp2 bondings and tendency of graphitization.


  • IPEN-DOC 25138

    SILVA, J.O.; NONATO, F.B.C.; SAMPAIO, F.G.A.; CALDAS, L.V.E. . Evaluation of some dosimetric properties of a dedicated plane parallel ionization chamber for radiotherapy electron beams. Brazilian Journal of Radiation Sciences, v. 6, n. 3, p. 1-13, 2018. DOI: 10.15392/bjrs.v6i3.547

    Abstract: Ionization chambers are the reference detectors for electron beam dosimetry. In this paper a dedicated radiotherapy plane parallel ionization chamber manufactured with low cost materials is presented for dosimetry in electron beams. The ionization chamber tested has a sensitive volume of 0.4 cm³. Both the collecting electrode and the guard ring were painted with a homogeneous mixture of nail polish and graphite. The dedicated ionization chamber presented a linear response with electron absorbed dose within the range 0.5 to 8.0 Gy, an increase of its response with the field size increasing, an angular dependence within ±5°, as recommended by international standards, and a polarity effect of 0.78% according to the field size. Considering the results obtained, it is possible to conclude that the plane parallel ionization chamber tested in this work presents potential use for elec - tron beam dosimetry in clinical routine.


  • IPEN-DOC 25137

    SELLERA, FABIO P.; GARGANO, RONALDO G.; ANJOS, CAROLINA dos; BAPTISTA, MAURICIO da S.; RIBEIRO, MARTHA S. ; POGLIANI, FABIO C.. Methylene blue-mediated antimicrobial photodynamic therapy: a novel strategy for digital dermatitis-associated sole ulcer in a cow – A case report. Photodiagnosis and Photodynamic Therapy, v. 24, p. 121-122, 2018. DOI: 10.1016/j.pdpdt.2018.09.004


  • IPEN-DOC 25136

    SANTOS, S.C. ; RODRIGUES JUNIOR, O. ; CAMPOS, L.L. . EPR response of yttria micro rods activated by europium. Journal of Alloys and Compounds, v. 764, p. 136-141, 2018. DOI: 10.1016/j.jallcom.2018.06.063

    Abstract: Rare earth (RE) materials present excellent properties, which importance is recognized worldwide. Innovation approaches in energy, medicine, communication, transportation, militarism, and radiation dosimetry consist in RE based materials. As yttrium oxide (Y2O3) exhibits intrinsic lattice characteristics that enable doping with others RE elements (Y2O3:RE), new materials with promising characteristics can be developed. This work aims to evaluate EPR response of europium-yttria (Y2O3:Eu) rods obtained by bio-prototyping. Ceramic rods containing up to 10 at.%Eu were irradiated with gamma doses from 0.001 to 150 kGy and evaluated by Electron Paramagnetic Resonance (EPR) at room temperature with X-band EPR. Based on results, Y2O3:Eu rods with 2 at.%Eu exhibited the most significant response, in which linear behavior arose from 0.001 up to 50 kGy. Fading and thermal annealing evaluations revealed that 2 at%.Eu improved dosimetric characteristics of yttria remarkably. These innovative findings afford that Y2O3:Eu is a promising material for radiation dosimetry.


  • IPEN-DOC 25135

    ROSSETTO, CLEUSA M.; ICHIKAWA, RODRIGO U. ; MARTINEZ, LUIS G. ; CAREZZATO, GERALDO L.; CARVALHO, ALEXANDRE M.G.; TURRILLAS, XAVIER. In situ hydration of sulfoaluminate cement mixtures monitored by synchrotron X-Ray diffraction. Materials Science Forum, v. 930, p. 153-157, 2018. DOI: 10.4028/

    Abstract: Mixtures of calcium sulfoaluminate and Portland clinkers with gypsum were hydrated with deionized water. The pastes were introduced in 0.7 mm borosilicate capillary tubes and kept at 40 ºC while diffraction patterns were collected every 35 s for approximately 3 hours with a monochromatic radiation of 12 keV at the XRD1 beamline of the Laboratório Nacional de Luz Síncrotron (LNLS) in Campinas, SP - Brazil. The main crystalline phases (C2S, C3S, ettringite, ye’elemite and gypsum) involved in the hydration were quantified by Rietveld analysis. The most noticeable fact was the absence of portlandite as a crystalline precipitate, most likely due to the capture of calcium ions to form ettringite.


  • IPEN-DOC 25134

    RICCI, GIANNINA; SANTOS, DANIEL W.; KOVACS, JOSEPH A.; NISHIKAKU, ANGELA S.; SANDES-FREITAS, TAINA V. de; RODRIGUES, ANDERSON M.; KUTTY, GEETHA; AFFONSO, REGINA ; SILVA, HELIO T.; MEDINA-PESTANA, JOSE O.; FRANCO, MARCELLO F. de; COLOMBO, ARNALDO L.. Genetic diversity of Pneumocystis jirovecii from a cluster of cases of pneumonia in renal transplant patients: Cross-sectional study. Mycoses, v. 61, n. 11, p. 845-852, 2018. DOI: 10.1111/myc.12823

    Abstract: Pneumocystis jirovecii can cause severe potentially life-threatening pneumonia (PCP) in kidney transplant patients. Prophylaxis of patients against PCP in this setting is usually performed during 6 months after transplantation. The aim of this study is to describe the molecular epidemiology of a cluster of PCP in renal transplant recipients in Brazil. Renal transplant patients who developed PCP between May and December 2011 had their formalin-fixed paraffin-embedded (FFPE) lung biopsy samples analysed. Pneumocystis jirovecii 23S mitochondrial large subunit of ribosomal RNA (23S mtLSU-rRNA), 26S rRNA, and dihydropteroate synthase (DHPS) genes were amplified by polymerase chain reaction (PCR), sequenced, and analysed for genetic variation. During the study period, 17 patients developed PCP (only four infections were documented within the first year after transplantation) and six (35.3%) died. Thirty FFPE samples from 11 patients, including one external control HIV-infected patient, had fungal DNA successfully extracted for further amplification and sequencing for all three genes. A total of five genotypes were identified among the 10 infected patients. Of note, four patients were infected by more than one genotype and seven patients were infected by the same genotype. DNA extracted from FFPE samples can be used for genotyping; this approach allowed us to demonstrate that multiple P. jirovecii strains were responsible for this cluster, and one genotype was found infecting seven patients. The knowledge of the causative agents of PCP may help to develop new initiatives for control and prevention of PCP among patients undergoing renal transplant and improve routine PCP prophylaxis.


  • IPEN-DOC 25133

    AKBARI-JEYHOUNI, REZA; OCHBELAGH, DARIUSH R.; MAIORINO, JOSE R.; DAURIA, FRANCESCO; STEFANI, GIOVANNI L. de . The utilization of thorium in Small Modular Reactors – Part I: neutronic assessment. Annals of Nuclear Energy, v. 120, p. 422-430, 2018. DOI: 10.1016/j.anucene.2018.06.013

    Abstract: This work presents a neutronic assessment to convert a Small Modular Reactor (SMR) with uranium core to the thorium mixed oxide core with minimum possible changes in the geometry and main parameters of SMR core. This option is due to most of SMR are designed to be strongly poisoned in the beginning of cycle and to have a long cycle. Thorium can be used as an absorber in the beginning of the cycle and also be used as a fertile material during the cycle, it seems to be a good option to use (Th/U)O2 as SMR’s fuel. The main neutronic objectives of this study is achieving longer cycle length for SMR by using the minimum possible amount of burnable poison and soluble boron in comparison with reference core. The Korean SMART reactor as a certified design SMR has been chosen as the reference core. The calculations have been performed by MCNP code for homogeneous and heterogeneous seed and blanket concept fuel assemblies. The results obtained show that the heterogeneous fuel assembly is the one which gives longer cycle length and used lower amount of burnable poison and soluble boron, and also consumes almost the same amount of 235U.


  • IPEN-DOC 25132

    PORFIRIO, DARILENA M.; MONTEIRO, LUCILENA R. ; COSTA, MARCONDES L. da. Rainwater geochemistry inside the Barcarena power station at the mouth of the Tocantins River. Environmental Technology, 2018. DOI: 10.1080/09593330.2018.1516801

    Abstract: Most of South America lacks studies on rainwater composition. The present study evaluates rainwater composition and bulk deposition inside Barcarena power station, located at the mouth of the Tocantins River with Amazon River in Brazil. In 2012, 24-h rainwater samples were collected inside the ELETRONORTE power plant (n = 93), and pH, EC, cations and anions were analyzed. In order of abundance, the rainwater ions were Na+ > Cl− > SO4−2 > Ca+2 > K+ > F− > Mg+2 > NH4+-N > NO3−-N. pH values ranged from 4.5 to 6.9, with 17 events with pH <5.6 and 5 events with pH < 5.0. Sodium and Cl− were the dominant ions with sea salt as main contribution. Acidity, enrichment factors and principal component analysis (PCA) indicate that F−, SO4−2 and NO3−-N in the rainwater came from anthropogenic sources. Fluoride correlated strongly (>0.85) with Ca+2 and Mg+2, likely originated from same source in the aluminum production chain. Potassium originated from a mixture of anthropogenic and natural sources, with a good correlation (>0.70) with NO3−-N and NH4+-N, indicating biomass burning and fertilizer origins. In 2012, Barcarena total bulk deposition ranged from 14,070 to 17,890 mg m−2 y−1 with significant contributions of SO4−2 (2,385 to 2,851 mg m−2 y−1), F− (419 to 479 mg m−2 y−1) and NO3−-N (128 to 280 mg m−2 y−1). EC values (4 to 254 µS cm−1) indicated a medium site pollution severity (> 175 µS cm−1), which increased the risk of damage to electrical components.


  • IPEN-DOC 25131

    POLO, IVON O. ; SANTOS, WILLIAM S. ; CALDAS, LINDA V.E. . Modelling the absorbed dose rate of the beta standard BSS2 147Pm source. Applied Radiation and Isotopes, v. 140, p. 83-86, 2018. DOI: 10.1016/j.apradiso.2018.06.015

    Abstract: The dosimetric measurements of 147Pm beta radiation beams have limitations due to their low energy, low dose rate, great dispersion and attenuation in air or tissue. In this work, the Monte Carlo model was developed for a 147Pm absorbed dose rate determination. This model consists of an extrapolation chamber and a 147Pm beta radiation source. Moreover, the absorbed dose rate was determined by experimental measurements and the MCNP Monte Carlo code was used. The relative number of particles that crossed the radioactive source window and the particles that crossed the extrapolation chamber entrance window were determined. The source fluence spectrum was also determined. The results of the simulation and the experimental calculations are in agreement with the absorbed dose rate from the PTB calibration certificate. The results obtained are considered acceptable, and they agree within the uncertainties. The difference between the experimental result and that from the Monte Carlo model, compared to that from the calibration certificate, was only 0.8% in both cases.


  • IPEN-DOC 25130

    POLO, IVON O. ; SANTOS, WILLIAM de S. ; CALDAS, LINDA V.E. . Determination of correction factors in beta radiation beams using Monte Carlo method. Applied Radiation and Isotopes, v. 140, p. 50-54, 2018. DOI: 10.1016/j.apradiso.2018.06.011

    Abstract: The absorbed dose rate is the main characterization quantity for beta radiation. The extrapolation chamber is considered the primary standard instrument. To determine absorbed dose rates in beta radiation beams, it is necessary to establish several correction factors. In this work, the correction factors for the backscatter due to the collecting electrode and to the guard ring, and the correction factor for Bremsstrahlung in beta secondary standard radiation beams are presented. For this purpose, the Monte Carlo method was applied. The results obtained are considered acceptable, and they agree within the uncertainties. The differences between the backscatter factors determined by the Monte Carlo method and those of the ISO standard were 0.6%, 0.9% and 2.04% for 90Sr/90Y, 85Kr and 147Pm sources respectively. The differences between the Bremsstrahlung factors determined by the Monte Carlo method and those of the ISO were 0.25%, 0.6% and 1% for 90Sr/90Y, 85Kr and 147Pm sources respectively.


  • IPEN-DOC 25129

    PILLIS, MARINA F. ; OLIVEIRA, MARA C.L. de; ANTUNES, RENATO A.. Surface chemistry and the corrosion behavior of magnetron sputtered niobium oxide films in sulfuric acid solution. Applied Surface Science, v. 462, p. 344-352, 2018. DOI: 10.1016/j.apsusc.2018.08.123

    Abstract: In this work, magnetron sputtered Nb2O5 films were obtained at two different deposition times. The surface chemistry of the deposited layers was investigated by X-ray photoelectron spectroscopy (XPS). The corrosion behavior was assessed by electrochemical impedance spectroscopy, potentiodynamic polarization and potentiostatic polarization tests in 0.5 M H2SO4 + 2 ppm HF solution at room temperature. The Nb5+/Nb4+ ratio decreased with the deposition time, leading to a higher surface activity for the film obtained at 30 min. This result was confirmed by its lower impedance values and higher current densities when compared to the 15′-film. Surface chemistry played a major role on the corrosion behavior of the sputtered films and can be tailored by the deposition time.


  • IPEN-DOC 25128

    PESQUEIRA, E.I.O.; MUSCI, C.S.; ROSSI, J.L. . Influence of the geometric characteristics of the mini-implants on mechanicals properties using artificial bone similar to anterior, middle and posterior regions of the jaws. Materials Science Forum, v. 930, p. 276-282, 2018. DOI: 10.4028/

    Abstract: The objective of this study was to identify the best torque of insertion and removal of mini-implants with a twin screw design (compact and self-drilling) into artificial bones with density and trabecular thickness, similar to anterior, middle and posterior regions of the jaws. Observation of the mini-implants surface using electron microscopy was performed before and after the tests. The torque values obtained during the insertion and removal was measured by digital torque wrench. The analyzed results led to the conclusion that the insertion and removal torques were larger with increase in bone density and cortical thickness. The design of the threads of the miniimplants influenced the insertion torque. Threads with smaller pitch increased the value of insertion torque. The anterior bone drilling installation reduces the insertion torque independent of bone density. Torque increased mainly by increasing the bone density and not necessarily with increased cortical thickness suggesting that the bone density of the trabecular bone must be considered in designing the installation of mini-implants.


  • IPEN-DOC 25127

    ORTIZ, NILCE ; LIMA, GISELLE N.S. ; NICOLAU, THAMIRES S.; REIS, ANNA C.S. . Solar/TiO2 photodecomposition and adsorption of tertiary antibiotics systems. International Journal of Latest Engineering and Management Research, v. 3, n. 6, p. 76-83, 2018.

    Abstract: The antibiotic residues are present usually in mixtures in soils and rivers sediment in the range of ng L-1 to μg L-1 around the world and cause, among many things, the proliferation of super-resistant bacteria. The study analyzes the efficiency of titanium dioxide (TiO2) and the solar photodecomposition of binary and tertiary systems of cephalexin, amoxicillin, and oxytetracicline from contaminated water discharges. The calculated kinetic constants of pseudo-first order, pseudo-second order and intraparticle diffusion confirm the better agreement with the pseudo-second-order. The isotherms parameters and constants of Langmuir, Freundlich, Redlich-Peterson (R-P) indicated the Langmuir and R-P isotherms have better correspondence, and the experimental results indicate 45% of removal percentage of antibiotics mixture in just 120 min of time stirring. The amoxicillin has the higher removal percentages followed by cephalexin and the lowest percentage was for oxytetraciclin. This behavior is explained by the chemical bond energy of the chemical structure, lower for amoxicillin increasing until the oxytetraccilin structure. The water treatment using Advanced Oxidative Processes - POA with TiO2 and solar radiation at different concentrations an mixtures of antibiotics followed by adsorption process rises as an efficient and ready to use water treatment to reach better water quality for reuse purposes.


  • IPEN-DOC 25126

    OLIVEIRA, J.R.B.; FINOCCHIARO, P.; AGODI, C.; BOZTOSUN, I.; CAPPUZZELLO, F.; FARIA, P.N. de; GASQUES, L.; LINARES, R.; MEDINA, N.H.; MENDES, D.R.; MORALLES, M. ; SOLACKI, S.O.; ZAGATTO, V.A.B.; ALCANTARA-NUNEZ, J.A.; GONZALEZ-ALVAREZ, M.A.; AGUIAR, V.A.P.; ESCUDEIRO, R.; KURMAN, V.. New spectrometer projects for challenging particle-gamma measurements of nuclear reactions. Journal of Physics: Conference Series, v. 1056, 2018. DOI: 10.1088/1742-6596/1056/1/012040

    Abstract: Two new gamma spectrometer projects are under development, both with some challenging technical characteristics in common, one for the investigation of weakly bound nuclear beam reactions at near barrier energies, and the other for the measurement of double charge exchange reactions in the 15-70 MeV per nucleon range. The first one is being developed and tested at the IFUSP, and the other is going to be built and installed at the LNS, INFN, under the NUMEN collaboration. The main characteristics of the two projects are presented and discussed.


  • IPEN-DOC 25125

    OLIVEIRA, JUSTINE P.R. ; MELENDEZ-ORTIZ, H.I.; BUCIO, EMILIO; ALVES, PATRICIA T.; LIMA, MAYARA I.S.; GOULART, LUIZ R.; MATHOR, MONICA B. ; VARCA, GUSTAVO H.C. ; LUGAO, ADEMAR B. . Current methods applied to biomaterials – characterization approaches, safety assessment and biological international standards. Current Topics in Medicinal Chemistry, v. 18, n. 4, p. 256-274, 2018. DOI: 10.2174/1568026618666180410151518

    Abstract: Safety and biocompatibility assessment of biomaterials are themes of constant concern as advanced materials enter the market as well as products manufactured by new techniques emerge. Within this context, this review provides an up-to-date approach on current methods for the characterization and safety assessment of biomaterials and biomedical devices from a physical-chemical to a biological perspective, including a description of the alternative methods in accordance with current and established international standards.


  • IPEN-DOC 25124

    NASCIMENTO, C.R.; ASFORA, V.K.; GONCALVES, J.A.C. ; KHOURY, H.J.; BARROS, V.S.M.; KALIL, L.F.; BUENO, C.C. . The performance of a multi guard ring (MGR) diode for clinical electron beams dosimetry. Applied Radiation and Isotopes, v. 141, p. 112-117, 2018. DOI: 10.1016/j.apradiso.2018.07.002

    Abstract: The dosimetric response of a multi guard ring structure (MGR) diode has been studied with clinical electron beam energies from 5 MeV to 15 MeV. The results showed that the MGR dose response is linear in the range of 5–320 cGy and presents reproducibility with variation coefficients less than 0.4%. The field output factors measured with the MGR agreed within 2% with those measured with an ionization chamber. This study evidences that this diode can be used for clinical electron beam dosimetry.


  • IPEN-DOC 25123

    NASCIMENTO, MAURICIO S.; FRANCO, ANTONIO T.R.; FRAJUCA, CARLOS; NAKAMOTO, FRANCISCO Y.; SANTOS, GIVANILDO A. dos; COUTO, ANTONIO A. . An experimental study of the solidification thermal parameters influence upon microstructure and mechanical properties of Al-Si-Cu alloys. Materials Research, v. 21, n. 5, 2018. DOI: 10.1590/1980-5373-MR-2017-0864

    Abstract: Metals solidification involves the transformation of the molten metal back into the solid state. Solidification structures impact heavily on the final product's characteristics. The microstructure effects on metallic alloys properties have been highlighted in various studies and particularly the dendrite arm spacing influence upon the mechanical properties such as tensile strength has been reported. In the present investigation, Al-10wt%Si-2wt%Cu and Al-10wt%Si-5wt%Cu alloys were directionally solidified upward under transient heat flow conditions. The experimental results include solidification thermal parameters such as tip growth rate and cooling rate, optical microscopy, volume fraction of the eutectic mixture, primary dendritic arm spacing and ultimate tensile strength. Experimental growth laws of primary dendrite arm spacing as a function of the solidification thermal parameters are proposed. The Hall-Petch mathematical expressions were used to correlate the ultimate tensile strength as a function of the primary dendritic arm spacing. It was found that the alloy with higher copper content had a more refined structure. More refined structures had higher ultimate tensile strength values.


  • IPEN-DOC 25122

    NANDENHA, J.; FONTES, E.H.; PIASENTIN, R.M. ; FONSECA, F.C. ; NETO, A.O. . Direct oxidation of methane at low temperature using Pt/C, Pd/C, Pt/C-ATO and Pd/C-ATO electrocatalysts prepared by sodium borohydride reduction process. Journal of Fuel Chemistry and Technology, v. 46, n. 9, p. 1137-1145, 2018. DOI: 10.1016/S1872-5813(18)30046-X

    Abstract: The main objective of this paper was to characterize the voltammetric profiles of the Pt/C, Pt/C-ATO, Pd/C and Pd/C-ATO electrocatalysts and study their catalytic activities for methane oxidation in an acidic electrolyte at 25°C and in a direct methane proton exchange membrane fuel cell at 80°C. The electrocatalysts prepared also were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The diffractograms of the Pt/C and Pt/C-ATO electrocatalysts show four peaks associated with Pt face-centered cubic (fcc) structure, and the diffractograms of Pd/C and Pd/C-ATO show four peaks associated with Pd face-centered cubic (fcc) structure. For Pt/C-ATO and Pd/C-ATO, characteristic peaks of cassiterite (SnO2) phase are observed, which are associated with Sb-doped SnO2 (ATO) used as supports for electrocatalysts. Cyclic voltammograms (CV) of all electrocatalysts after adsorption of methane show that there is a current increase during the anodic scan. However, this effect is more pronounced for Pt/C-ATO and Pd/C-ATO. This process is related to the oxidation of the adsorbed species through the bifunctional mechanism, where ATO provides oxygenated species for the oxidation of CO or HCO intermediates adsorbed in Pt or Pd sites. From in situ ATR-FTIR (Attenuated Total Reflectance-Fourier Transform Infrared) experiments for all electrocatalysts prepared the formation of HCO or CO intermediates are observed, which indicates the production of carbon dioxide. Polarization curves at 80°C in a direct methane fuel cell (DMEFC) show that Pd/C and Pt/C electroacatalysts have superior performance to Pd/C-ATO and Pt/C-ATO in methane oxidation.


  • IPEN-DOC 25120

    MUTARELLI, RITA de C. ; LIMA, ANA C. de S. ; SABUNDJIAN, GAIANE . Comparative study of methodologies for measuring corporate social responsibility. International Journal of Development Research, v. 8, n. 6, p. 20894-20903, 2018.

    Abstract: The Corporate Social Responsibility (CSR) is a current issue increasingly present in the strategic planning of the companies. Although managers of public or private organizations have turned their attention to social and environmental issues in their strategic actions, measuring the social responsibility of a company is not an easy task. This paper aims to observe the eight most relevant methodologies of CSR measurement and establish a comparative analysis among them by considering the scope and feasibility of each methodology. The most relevant CSR methodologies were selected. The main characteristics of each of the eight tools were observed and compared. The results demonstrated that although most methodologies have strong measuring characteristics the Ethos Indicators consist of the most effective tool for measuring CSR mainly regarding the institutional issues


  • IPEN-DOC 25119

    MURATA, H.M.; MORALLES, M. ; BONIFACIO, D.A.B.. Evaluation of digital methods for energy calculation and timing pick-off in positron emission tomography. Journal of Instrumentation, v. 13, n. P09024, 2018. DOI: 10.1088/1748-0221/13/09/P09024

    Abstract: Traditionally, pulse processing in Positron Emission Tomography (PET) has been based on analog or discrete circuits forming a decentralized processing system. However, there is a convergence for digital and integrated implementations due to the characteristics of the modern electronic devices which are real-time processing capable, such as Application-Specific Integrated Circuit (ASIC) and Field Programmable Gate Array (FPGA) with fast Analog to Digital Converters (ADC). However, FPGA can provide fast implementation at relatively low cost and also enables the development of sophisticated digital pulse processing algorithms to improve energy, position and time resolutions in PET systems. Our group has developed and evaluated one energy calculation and three timing pick-off methods for implementation onto an FPGA-based system. For a typical PET detector setup, our charge integration method presents energy resolution similar to previously designed PET detectors. The best performance for timing pick-off was achieved by the Initial Rise Interpolation (IRI) method, where a coincidence time resolution of around 440 ps is suitable for Time of Flight (TOF) PET. Future works include embedding the proposed algorithms in a FPGAbased data acquisition system under development by our group which will be employed in a PET prototype.


  • IPEN-DOC 25118

    MUCSI, C.S. ; REIS, L.A.M. dos; GOMES, M.P. ; PEREIRA, L.A.T. ; ROSSI, J.L. . Study on the viability of the recycling by electric arc melting of zirconium alloys scraps aiming the scalability of the process. Materials Science Forum, v. 930, p. 495-500, 2018. DOI: 10.4028/

    Abstract: Turning chips of zirconium alloys are produced in large quantities during the machining of alloy rods for the fabrication of the end plugs for the Pressurized Water Reactor (PWR) fuel elements parts of Angra II nuclear reactor (Brazil – Rio de Janeiro). This paper presents a study on the search for an efficient way for the cleaning, quality control and Vacuum Arc Remelting (VAR) of pressed zirconium alloys chips to produce a material viable to be used in the production of the fuel rod end plugs. The process starts with cutting oil clean out. The first step in this process consists in soaking a bunch of chips in clean water, to remove soluble cutting oils, followed by an alkaline degreasing bath and a wash with a high-pressure flow of water. Drying is performed by a flux of warm air. The oil free chips are then subjected to a magnet in order to detect and collect any magnetic material, essentially ferrous, that may be present in the original chips. Samples of the material are collected and then melted in a small non consumable electrode vacuum arc furnace for evaluation by Energy Dispersive X-ray Fluorescence Spectrometry (EDXRFS) in order to define the quality of the chips. The next step consists in the 15 ton hydraulic pressing the chips in a die with 40 mm square section and 500 mm long, producing an electrode with 20% of the Zircaloy bulk density. The electrode was finally melted in a laboratory scale modified VAR furnace located at the CCTM–IPEN, producing 0.8 kg ingots. The authors conclude that the samples obtained from the fuel element industry can be melting in a VAR furnace, modified to accommodate low density electrodes, allowing a reduction up to 40 times the original storage volume, however, it is necessary to remelt the ingots to correct their composition in order to recycle the original zirconium alloys chips. in a process to reduce volume and allow the reutilization of valuable Zircaloy scraps.


  • IPEN-DOC 25117

    MUCCILLO, R. ; ESPOSITO, V.; FLORIO, D.Z. de; MUCCILLO, E.N.S. . Electric field-assisted pressureless sintering gadolinium-, yttrium- and samarium-doped barium cerate. Scripta Materialia, v. 156, p. 6-9, 2018. DOI: 10.1016/j.scriptamat.2018.07.005

    Abstract: Gadolinium-, yttrium- and samarium-doped barium cerate compounds were sintered either conventionally at 1500 °C or applying an electric field at 1200 °C. The combined results of dilatometry and impedance spectroscopy measurements in electric field-assisted sintered specimens show substantial improvement of the electrical conductivity. Improved grain-to-grain contact and the thermal removal of depleted chemical species due to Joule heating at the space charge region are proposed as the main mechanisms for the increase of both the grain boundary and the bulk electrical conductivities, respectively.


  • IPEN-DOC 25116

    MOREIRA, TIANA C.L.; AMATO-LOURENCO, LUIS F.; SILVA, GISELA T. da; ANDRE, CARMEN D.S. de; ANDRE, PAULO A. de; BARROZO, LIGIA V.; SINGER, JULIO M.; SALDIVA, PAULO H.N.; SAIKI, MITIKO ; LOCOSSELLI, GIULIANO M.. The use of tree barks to monitor traffic related air pollution: a case study in São Paulo–Brazil. Frontiers in Environmental Science, v. 6, n. 72, p. 1-12, 2018. DOI: 10.3389/fenvs.2018.00072

    Abstract: The analysis of chemical elements in the barks of trees is an alternative procedure to access spatial heterogeneity of traffic related air pollution. However, the role of tree species in the characterization of the variability of airborne pollution is poorly known. We present an observational study conducted in São Paulo, Brazil, based on the analysis of 498 trees from three common species: Tipuana tipu, Poincianella pluviosa, and Ligustrum sp. We considered ANCOVA models to compare the concentrations of Al, Fe, Zn, Cu, Mn, Ba, and S in the bark (periderm) of trees located close to streets with different levels of traffic intensity controlling for the extension of nearby green areas. The expected trend of increasing elemental concentration in the bark of trees located near streets with greater traffic intensity or close to smaller green areas was only fully evidenced by T. tipu. For instance, the concentrations of Zn, Fe, Al, and Ba increase by 200, 350, 230, and 280% respectively, for trees of this species located near arterial streets when compared to those observed near local streets. On the other hand, the concentrations of Zn, Fe, Al, and Ba are reduced by 41, 45, 50, and 30%, respectively, for trees located near green areas. For P. pluviosa, the capacity to suggest an association between the tree bark concentration of chemical elements with increasing levels of air pollution and presence of green areas was only fully observed for Zn and Cu. For Ligustrum sp., weaker and sometimes non-expected associations between bark concentrations of the chemical elements and either street classification or green area extension were observed. Our results indicate that the choice of species is a key element in the use of tree barks as a biomonitoring tool in urban landscapes. Species like T. tipu, with rough and highly porous bark, are the most appropriate for such purpose.


  • IPEN-DOC 25115

    MOREIRA, GREGORI de A. ; GUERRERO-RASCADO, JUAN L.; BRAVO-ARANDA, JUAN A.; BENAVENT-OLTRA, JOSE A.; ORTIZ-AMEZCUA, PABLO; ROMAN, ROBERTO; BEDOYA-VELASQUEZ, ANDRES E.; LANDULFO, EDUARDO ; ALADOS-ARBOLEDAS, LUCAS. Study of the planetary boundary layer by microwave radiometer, elastic lidar and Doppler lidar estimations in Southern Iberian Peninsula. Atmospheric Research, v. 213, p. 185-195, 2018. DOI: 10.1016/j.atmosres.2018.06.007

    Abstract: The Planetary Boundary Layer (PBL) is a relevant part of the atmosphere with a variable extension that clearly plays an important role in fields like air quality or weather forecasting. Passive and active remote sensing systems have been widely applied to analyze PBL characteristics. The combination of different remote sensing techniques allows obtaining a complete picture on the PBL dynamic. In this study, we analyze the PBL using microwave radiometer, elastic lidar and Doppler lidar data. We use co-located data simultaneously gathered in the framework of SLOPE-I (Sierra Nevada Lidar aerOsol Profiling Experiment) campaign at Granada (Spain) during a 90- day period in summer 2016. Firstly, the PBL height (PBLH) obtained from microwave radiometer data is validated against PBLH provided by analyzing co-located radiosondes, showing a good agreement. In a second stage, active remote sensing systems are used for deriving the PBLH. Thus, an extended Kalman filter method is applied to data obtained by the elastic lidar while the vertical wind speed variance method is applied to the Doppler lidar. PBLH′s derived by these approaches are compared to PBLH retrieved by the microwave radiometer. The results show a good agreement among these retrievals based on active remote sensing in most of the cases, although some discrepancies appear in instances of intense PBL changes (either growth and/or decrease).


  • IPEN-DOC 25114

    MATOS, BRUNO R. ; POLITANO, RODOLFO ; REY, JOSE F.Q.; HERMIDA-MERINO, DANIEL; SCHADE, ULRICH; PUSKAR, LJILJANA; FONSECA, FABIO C. . Interplay of alpha/beta-relaxation dynamics and the shape of ionomer building blocks. Scientific Reports, v. 8, n. 13441, 2018. DOI: 10.1038/s41598-018-31368-8

    Abstract: The relation between the alpha/beta relaxations and the shape of the building blocks of ionomer materials is a key factor for programming an important temperature-dependent property: the memory of shape. However, the morphology of ionomers is indirectly obtained via modeling of small angle X-ray scattering (SAXS) data owing to the hardly accessible image characterization of the nanometric building blocks-micelle-like cylindrical polymeric aggregates (radius similar to 2-6 nm and length >100 nm). Herein, broadband dielectric spectroscopy (BDS) measurements, free from electrode polarization effects, allowed identifying the time and temperature dependence of the polarization of different length scales of the ionomer matrix, and more importantly, by directly providing the aspect ratio of the radius and length of the polymeric aggregates for each desired temperature. This finding is essential for controlling the shape of ionomer based functional products under several stimuli conditions, thereby advancing remarkable applications, such as four dimensional (4D) printing.


  • IPEN-DOC 25113

    MARTINS, JOAO F.T. ; SANTOS, ROBINSON A. dos ; FERRAZ, CAUE de M. ; OLIVEIRA, RENE R. ; FIEDERLE, MICHAEL; AMADEU, RAFAEL de A. ; SANTOS, RODRIGO S. dos ; SILVA, THIAGO L.B. da; HAMADA, MARGARIDA M. . Optimization of the HgI2 Crystal preparation for application as a radiation semiconductor detector. Studies in Engineering and Technology, v. 5, n. 1, p. 76-88, 2018. DOI: 10.11114/set.v5i1.3149

    Abstract: The effect of HgI2 crystal encapsulation using different polymer resins, with the intent of avoiding the oxidation of the crystal surface, was evaluated in this work. The crystal was purified and grown by the physical vapor transport (PVT) technique modified. Systematic measurements were carried out for evaluating the stoichiometry, structure orientation, surface morphology and impurity of the crystal grown. The purer region of the crystal grown was selected to be prepared as a radiation detector, applying water-based conductive ink contacts and copper wire on the crystal surfaces. After that, the crystal was encapsulated with a polymeric resin which insulates atmospheric gases, aiming to improve the stability of the HgI2 detector. Four resins were used for crystal encapslation and the performance of the detector depended on the composition of the resins used. Among the four resins studied to evaluate the influence of encapsulation on the performance of crystals, as a radiation detector, the best result of resistivity and energy spectrum was obtained for the resin #3 (50% - 100% of Methylacetate and 5% - 10% of n-butylacetate). The encapsulation of crystals with polymer resins, performed with the intent of avoiding the oxidation of the crystal surface, did not compromise the measurements and were fully capable of detecting the presence of gamma radiation. The stability of the encapsulated HgI2 crystal detector was of up to 78 hs, while the stability found for HgI2 detector no encapsulated was in order 3 ~4 hs.


  • IPEN-DOC 25112

    MARIANO, DOUGLAS O.C.; MESSIAS, MARCELA Di G. ; PREZOTTO-NETO, JOSE P. ; SPENCER, PATRICK J. ; PIMENTA, DANIEL C.. Biochemical analyses of proteins from duttaphrynus melanostictus (Bufo melanostictus) skin secretion: soluble protein retrieval from a viscous matrix by ion-exchange batch sample preparation. Protein Journal, v. 37, n. 4, p. 380-389, 2018. DOI: 10.1007/s10930-018-9780-z

    Abstract: A crucial step in scientific analysis can be sample preparation, and its importance increases in the same rate as the sensitivity of the following employed/desired analytical technique does. The need to analyze complex, viscous matrices is not new, and diverse approaches have been employed, with different success rates depending on the intended molecules. Solid-phase extraction, for example, has been successfully used in sample preparation for organic molecules and peptides. However, due to the usual methodological conditions, biologically active proteins are not successfully retrieved by this technique, resulting in a low rate of protein identification reported for the viscous amphibian skin secretion. Here we describe an ion-exchange batch processing sample preparation technique that allows viscous or adhesive materials (as some amphibian skin secretions) to be further processed by classical liquid chromatography approaches. According to our protocol, samples were allowed to equilibrate with a specific resin that was washed with appropriated buffers in order to yield the soluble protein fraction. In order to show the efficiency of our methodology, we have compared our results to classically prepared skin secretion, i.e., by means of filtration and centrifugation. After batch sample preparation, we were able to obtain reproductive resolved protein chromatographic profiles, as revealed by SDS-PAGE, and retrieve some biological activities, namely, hydrolases belonging to serine peptidase family. Not only that, but also the unbound fraction was rich in low molecular mass molecules, such as alkaloids and steroids, making this sample preparation technique also suitable for the enrichment of such molecules.


  • IPEN-DOC 25110

    UCO, DAYANE P.; LEITE-SILVA, VANIA R.; SILVA, HERON D.T.; DUQUE, MARCELO D.; GRICE, JEFFREY; MATHOR, MONICA B. ; ANDREO-FILHO, NEWTON; LOPES, PATRICIA S.. UVA and UVB formulation phototoxicity in a three-dimensional human skin model: photodegradation effect. Toxicology in Vitro, v. 53, p. 37-44, 2018. DOI: 10.1016/j.tiv.2018.07.009

    Abstract: In vitro three-dimensional human skin models are an innovative alternative to evaluate cytotoxicity and phototoxicity in the cosmetic industry. The aim of this study was to use a skin model to evaluate the potential toxicity of sunscreen formulations with or without exposure to UV radiation. In addition, the toxicity of these formulations was evaluated after exposure to photodegradation. The results showed toxicity with all formulations/conditions tested, including the control formulation, compared to PBS. Cell viability of photodegraded formulations - prior to the phototoxicity radiation process - was higher, indicating that some formulation components were degraded into products with reduced toxicity. The results also indicated that avobenzone was more unstable/toxic than octyl p-methoxycinnamate under the same test conditions. The sunscreens and their formulations were shown to be toxic to skin model cells to some extent, even when not exposed to UV irradiation; however the biological role of this toxicity is unclear. This result shows the importance of testing sunscreen formulations in real in-use conditions. Finally, since we used an in vitro assay based on a human cell model, this non-invasive technique represents a suitable alternative to animal models for phototoxicity tests in general and could have application in screening new sunscreen products.


  • IPEN-DOC 25109

    LEAL, GEORGIA B. ; CIOTTI, LIGIA; WATACABE, BEATRIZ N. ; SILVA, DANIELA C.L. da ; ANTONIASSI, RODOLFO M. ; SILVA, JULIO C.M. ; LINARDI, MARCELO ; GIUDICI, REINALDO; VAZ, JORGE M. ; SPINACE, ESTEVAM V. . Preparation of Au/TiO2 by a facile method at room temperature for the CO preferential oxidation reaction. Catalysis Communications, v. 116, p. 38-42, 2018. DOI: 10.1016/j.catcom.2018.07.021

    Abstract: A simple strategy was used to prepare Au/TiO2 catalyst at room temperature. Au nanoparticles were initially prepared in solution using HAuCl4.3H2O as Au precursor, sodium citrate as stabilizing agent and sodium borohydride as reducing agent. The preformed Au nanoparticles were further supported on TiO2 and the resulting solid material was characterized by Energy-dispersive X-ray spectroscopy, X-ray diffraction and Transmission Electron Microscopy and tested for the preferential oxidation of carbon monoxide in hydrogen-rich stream (COPROX reaction). The obtained Au/TiO2 catalyst consisted of Au nanoparticles with an average size of ~ 4 nm and showed excellent catalytic performance in the 20-50 °C low-temperature range. In particular, at 40 °C a CO conversion of 99.5% and CO2 selectivity of 45% were obtained using an O2/CO ratio of 2 (1 vol% CO, λ=4) and 97 vol% H2 in the feed gas stream (GHSV=15,000 mL gcat −1 h−1).


  • IPEN-DOC 25108

    LARROZA, ELIANE G. ; KECKHUT, PHILIPPE; BARAY, JEAN-LUC; NAKAEMA, WALTER M.; VEREMES, HELENE; LANDULFO, EDUARDO ; DIONISI, DAVIDE; KHAYKIN, SERGEY; RAVETTA, FRANCOIS. Long-range transport of water channelized through the southern subtropical jet. Atmosphere, v. 9, n. 10, 2018. DOI: 10.3390/atmos9100374

    Abstract: In this study, an air mass (containing a cirrus cloud) was detected by light detection and ranging (lidar) above São Paulo (Brazil) in June 2007 and tracked around the globe, thanks to Lagrangian calculations as well as ground-based and satellite observations. Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data were also used to provide locations of occurrence of cirrus around the globe and extract their respective macro physical parameters (altitude and temperature). An analysis of the air mass history based on Lagrangian trajectories reveals that water coming from the Equator is channelized through the southern subtropical jet for weeks. In this case, the back-trajectories showed that the cirrus cloud detected at São Paulo was a mixture of air masses from two different locations: (1) the active convective area located around the Equator, with transport into the upper troposphere that promotes cirrus cloud formation; and (2) the South Pacific Ocean, with transport that follows the subtropical jet stream (STJ). Air masses coming from equatorial convective regions are trapped by the jet, which contributes to maintaining the lifetime of the cirrus cloud for a few days. The cloud disappears near the African continent, due to a southern excursion and warmer temperatures, then reappears and is detected again by the lidar system in São Paulo after 12 days. The observed cloud is located at a similar altitude, revealing that sedimentation is small or compensated by radiative uplift.


  • IPEN-DOC 25106

    KAFER, KARINE A.; BERNARDI, HEIDE H.; SANTOS, OSMAR de S.; OTUBO, LARISSA ; LIMA, NELSON B. de ; OTUBO, JORGE. The influence of microstructure and mechanical resistance on the shape memory of ECAE processed stainless Fe-Mn-Si-Cr-Ni-Co steel. Materials Research, v. 21, n. 5, 2018. DOI: 10.1590/1980-5373-MR-2017-0958

    Abstract: In the current work, XRD, SEM, EBSD and TEM techniques were used to evaluate the microstructure of stainless Fe-Mn-Si-Cr-Ni-Co shape memory steel processed by ECAE and annealed for one hour at temperatures ranging from 650ºC to 950ºC. The results were then correlated with the mechanical and shape-memory properties of the steel. It was observed that the samples containing large grains and a microstructure free of defects or precipitates presented a high volume fraction of multi-variant thermal martensite and stress-induced martensite, resulting in good shape recovery, owing to the memory effect. The grain refinement and precipitation of second-phase particles decreased the volume fraction and number of martensite variants and considerably increased the mechanical resistance, enhancing the elastic shape recovery. It was shown that shape memory properties were essentially related to the mechanical resistance of the matrix, which in turn was related to the microstructure.


  • IPEN-DOC 25105

    SOUZA, SAMIRA H.J.; MACHADO, ALANA C.; LOPES, RAQUEL M.; ZEZELL, DENISE M. ; SCARAMUCCI, TAIS; ARANHA, ANA C.C.. Effectiveness and acid/tooth brushing resistance of in-office desensitizing treatments - a hydraulic conductance study. Archives of Oral Biology, v. 96, p. 130-136, 2018. DOI: 10.1016/j.archoralbio.2018.09.004

    Abstract: Objective: To evaluate dentin permeability and tubule occlusion of in-office desensitizing treatments, and to analyze their resistance to erosive/abrasive challenges. Design: Ninety-one 1mm-thick dentin discs were immersed in EDTA solution for 5 min. After analyzing the maximum dentin permeability, the specimens were randomly allocated into 7 experimental groups (n=10): Control (no treatment); Er,Cr:YSGG laser; Nd:YAG laser; Gluma Desensitizer; Duraphat; Pro-Argin toothpaste; Calcium Sodium Phosphosilicate (CSP) paste. The post-treatment permeability was assessed and then the specimens were subjected to a 5-day erosion-abrasion cycling protocol: 4x/day of immersion in citric acid solution (5 min;0.3%), followed by exposure to clarified human saliva (60 min). After the first and last acid challenges, specimens were brushed for 15 s, with exposure to the toothpaste slurry for total time of 2 min. Dentin permeability was re-measured (post-cycling). Percentage of dentin permeability for each experimental time was calculated in relation to the maximum permeability (%Lp). Data were analyzed with 2-way repeated measures ANOVA and Tukey tests (α=0.05). Surface modifications were analyzed by scanning electron microscopy. Results: In both experimental time CSP paste and Gluma Desensitizer did not differ from each other (p=0.0874), and were the only groups that presented significantly lower %Lp than the Control (p=0.026 and p=0.022, respectively). After treatment, they were able to reduce dentin permeability in 82% and 72%, respectively. The %Lp post-cycling was higher than post-treatment value for all groups (p=0.008). Dentin permeability increased 21% for CSP paste and 12% for Gluma, but they remained significant different from Control. Deposits on the surface were observed for CSP paste; and for Gluma, tubule diameters were shown to be smaller. Conclusions: CSP paste and Gluma Desensitizer were the only treatments able to decrease dentin permeability post-treatment and to sustain low permeability post-cycling.


  • IPEN-DOC 25104

    JIMENEZ-VILLAR, ERNESTO ; XAVIER, M.C.S.; WETTER, NIKLAUS U. ; MESTRE, VALDECI; MARTINS, WELITON S.; BASSO, GABRIEL F.; ERMAKOV, V.A.; MARQUES, F.C.; SA, GILBERTO F. de. Anomalous transport of light at the phase transition to localization: strong dependence with incident angle. Photonics Research, v. 6, n. 10, p. 929-942, 2018. DOI: 10.1364/PRJ.6.000929

    Abstract: There has been a growing interest in disordered optical media in recent years due to their potential applications in solar collectors, random lasers, light confinement, and other advanced photonic functions. This paper studies the transport of light for different incidence angles in a strongly disordered optical medium composed of core-shell TiO2@Silica nanoparticles suspended in an ethanol solution. A decrease of optical conductance and an increase of absorption near the input border are reported when the incidence angle increases. The specular reflection, measured for the photons that enter the sample, is lower than the effective internal reflection undergone by the coherently backscattered photons in the exact opposite direction, indicating a nonreciprocal propagation of light. This study represents a novel approach in order to understand the complex physics involved at the phase transition to localization.


  • IPEN-DOC 25103

    ICHIKAWA, R.U. ; LINHARES, H.S.M.D.; PERAL, I.; BALDOCHI, S.L. ; RANIERI, I.M. ; TURRILLAS, X.; MARTINEZ, L.G. . Evidence for a core–shell configuration in Tb-doped KY3F10 nanoparticles using synchrotron x-ray line profile and pair distribution function analyses. Materials Research Express, v. 5, n. 1, 2018. DOI: 10.1088/2053-1591/aaa0bc

    Abstract: The microstructure of Tb-doped KY3F10 nanoparticles synthesized by coprecipitation was analysed using x-ray synchrotron diffraction data. Size-strain analysis was performed by means of x-ray line profile (XLPA) methods such as Warren–Averbach and whole powder pattern modelling. Additionally, the structural coherence of the sample was accessed using pair distribution function analysis, supporting the XLPA results. The combination of all methods revealed that the nanoparticles exhibit a more ordered core and a less ordered surface comprising a core–shell configuration.


  • IPEN-DOC 25102

    HAZENFRATZ, R. ; MUNITA, C.S. ; NEVES, E.G.. Neural networks (SOM) applied to INAA data of chemical elements in archaeological ceramics from Central Amazon. Science & Technology of Archaeological Research, v. 3, n. 2, SI, p. 334-340, 2017. DOI: 10.1080/20548923.2018.1470218

    Abstract: Artificial neural networks represent an alternative to traditional multivariate techniques, such as principal component and discriminant analysis, which rely on hypotheses regarding the normal distribution of the data and homoscedasticity. They also may be a powerful tool for multivariate modeling of systems that do not present linear correlation between variables, as well as to visualize high-dimensional data in bi- or trivariate structures. One special kind of neural network of interest in archaeometric studies is the Self-Organizing Map (SOM). SOMs can be distinguished from other neural networks for preserving the topological features of the original multivariate space. in this study, the self-organizing maps were applied to concentration data of chemical elements measured in archaeological ceramics from Central Amazon using instrumental neutron activation analysis (INAA). The main objective was testing the chemical patterns previously identified using cluster and principal component analysis, forming groups of ceramics according the multivariate chemical composition. It was verified by statistical tests that the chemical elemental data was not normally distributed and did not present homogeneity of covariance matrices for different groups, as requested by principal component analysis and other multivariate techniques. The maps obtained were consistent with the patterns identified by cluster and principal component analysis, forming two chemical groups of pottery shards for each archaeological site tested. Finally, it was verified the potential of SOMs for testing if failures in underlying hypotheses of traditional multivariate techniques might be critically influencing the results and subsequent archaeological interpretation of archaeometric data.


  • IPEN-DOC 25100

    GUEDES-SILVA, CECILIA C. ; RODAS, ANDREA C.D.; SILVA, ANTONIO C. ; RIBEIRO, CHRISTIANE; CARVALHO, FLAVIO M. de S.; HIGA, OLGA Z. ; FERREIRA, THIAGO dos S.. Microstructure, mechanical properties and in vitro biological behavior of silicon nitride ceramics. Materials Research, v. 21, n. 6, 2018. DOI: 10.1590/1980-5373-MR-2018-0266

    Abstract: The bioinert surface of silicon nitride ceramics led us to investigate the additions of SiO2, CaO and Al2O3 in order to aid the liquid phase sintering and improve the mechanical properties and biological behavior of the final materials. The sintered materials reached ca. 97% of theoretical density and total α→β-Si3N4 transformation. The samples had relatively high values of fracture toughness while their elastic modulus values were lower than those of conventional silicon nitride ceramics. Apatite deposits were observed on the surfaces analyzed after SBF (simulated body fluid) immersions, suggesting their bioactivity. Osteoblasts proliferation and calcified matrix were also detected as response to cells/ materials contact. This combination of properties suggests that all studied compositions are promising for applications in biomedical devices. Moreover, compositions with alumina additions and higher silica content had better in vitro biological behavior, densification and mechanical properties, suggesting greater potential to be used in bone substitute devices.


  • IPEN-DOC 25099

    GUALTEROS, JESUS A.D.; GARCIA, MARCO A.S.; SILVA, ANDERSON G.M. da; RODRIGUES, THENNER S. ; CANDIDO, EDUARDO G. ; SILVA, FELIPE A. e ; FONSECA, FABIO C. ; QUIROZ, JHON; OLIVEIRA, DANIELA C. de; TORRESI, SUSANA I.C. de; MOURA, CARLA V.R. de; CAMARGO, PEDRO H.C.; MOURA, EDMILSON M. de. Synthesis of highly dispersed gold nanoparticles on Al2O3, SiO2, and TiO2 for the solvent-free oxidation of benzyl alcohol under low metal loadings. Journal of Materials Science, v. 54, n. 1, p. 238-251, 2019. DOI: 10.1007/s10853-018-2827-x

    Abstract: We reported the organic template-free synthesis of gold (Au) nanoparticles (NPs) supported on TiO2, SiO2, and Al2O3 displaying uniform Au sizes and high dispersions over the supports. The Au-based catalysts were prepared by a deposition– precipitation method using urea as the precipitating agent. In the next step, the solvent-free oxidation of benzyl alcohol was investigated as model reaction using only 0.08–0.05 mol% of Au loadings and oxygen (O2) as the oxidant. Very high catalytic performances (TOF up to 443,624 h-1) could be achieved. Specifically, we investigated their catalytic activities, selectivity, and stabilities as well as the role of metal–support interactions over the performances. The conversion of the substrate was found to be associated with the nature of the employed support as the Au NPs presented similar sizes in all materials. A sub-stoichiometric amount of base was sufficient for the catalyst activation and the observation of the catalysts profile over the time enable insights on their recyclability performances. We believe this reported method represents a facile approach for the synthesis of uniform Au-supported catalysts displaying high performances.


  • IPEN-DOC 25098

    GONSALVES, TAYARA C. ; SILVA, FRANKS M.; VIEIRA, LIGIA S.; CASINI, JULIO C.S.; FARIA, RUBENS N. de . Electrochemical characteristics and microstructures of activated carbon powder supercapacitors for energy storage. Materials Science Forum, v. 930, p. 597-602, 2018. DOI: 10.4028/

    Abstract: In recent years, extensive investigations have focused on the study and improvement of supercapacitor electrode materials. The electric devices produced with these materials are used to store energy over time periods ranging from seconds to several days. The main factor that determines the energy storage period of a supercapacitor is its self-discharge rate, i.e., the gradual decrease in electric potential that occurs when the supercapacitor terminals are not connected to either a charging circuit or electric load. Self-discharge is attenuated at lower temperatures, resulting in an increased energy storage period. This paper addresses the temperature-dependence of self-discharge via a systematic study of supercapacitors with nominal capacitances of 1.0 and 10.0 F at DC potentials of 5.5 and 2.7 V, respectively. The specific capacitances, internal resistances, and self-discharge characteristics of commercial activated carbon electrode supercapacitors were investigated. Using cyclic voltammetry, the specific capacitances were determined to be 44.4 and 66.7 Fg−1 for distinct carbon electrode supercapacitors. The self-discharge characteristics were investigated at both room temperature and close to the freezing point. The internal resistances of the supercapacitors were calculated using the discharge curves at room temperature. The microstructures of the electrode materials were determined using scanning electron microscopy.


  • IPEN-DOC 25097

    GONCALVES, KARINA de O.; VIEIRA, DANIEL P. ; COURROL, LILIA C.. Study of THP-1 macrophage viability after sonodynamic therapy using methyl ester of 5-aminolevulinic acid gold nanoparticles. Ultrasound in Medicine & Biology, v. 44, n. 9, p. 2009-2017, 2018. DOI: 10.1016/j.ultrasmedbio.2018.05.012

    Abstract: Sonodynamic therapy (SDT) is emerging as new atherosclerosis treatment. The use of gold nanoparticles (AuNPs) as the vehicle for a sensitizer delivery improves reactive oxygen species formation. In this study, methyl ester of aminolevulinic acid (MALA) gold nanoparticles (MALA:AuNPs) functionalized with polyethylene glycol (PEG) were synthesized by photoreduction and characterized by ultraviolet/visible optical absorption, zeta potential and electron microscopy. The reactive oxygen species generation induced by ultrasound irradiation of MALA:AuNPs solutions was studied by observing the decrease in the 1,3-diphenylisobenzofuran emission band. The potential use of MALA:AuNPs as sensitizer for sonodynamic therapy was investigated on THP-1 macrophages. The cytotoxicity test was also described. The findings suggested that ultrasound combined with MALA:AuNPs provides impressive results in in vitro studies. Sonodynamic therapy with MALA:AuNPs through 2 minutes of ultrasound exposure (1 MHz and 1 W/cm2) culminated with total macrophage reduction. Thus, sonodynamic therapy combined with MALA:AuNPs has potential as a treatment for atherosclerosis.


  • IPEN-DOC 25096

    GOMES, MAURILIO P. ; SANTOS, IGOR P. dos ; COUTO, CAMILA P. ; BETINI, EVANDRO G. ; REIS, LUIS A.M. dos ; MUCSI, CRISTIANO S. ; COLOSIO, MARCO A.; ROSSI, JESUALDO L. . Heat treatment of sintered valve seat inserts. Materials Research, v. 21, n. 5, 2018. DOI: 10.1590/1980-5373-MR-2018-0068

    Abstract: The characterization of sintered valve seat inserts (VSIs) after being subjected to different heat treatment operations has been carried out. The VSIs were obtained from three different alloys by mixing iron powder with AISI M3:2, AISI M2 high-speed steels, and AISI D2 tool steel. After sintering, the VSI were quenched in air followed by double tempering at seven different temperatures. The cooling rate during air quenching was measured by means of a thermocouple type k attached to a data acquisition system. The characterization of the mechanical and physical properties of the VSIs was achieved by measuring relative density, apparent hardness and crush radial strength. The resulting microstructures for the sintered parts were interpreted using the isothermal and continuous cooling transformation diagrams for similar alloys. The VSI obtained with AISI M3:2 and AISI M2 high-speed steels after air quenching and double tempering at 600 ºC showed the best results in terms of apparent hardness and crush radial strength.


  • IPEN-DOC 25095

    GENARO, ISABELLA S. de; ALMEIDA, FRANCINE M. de; HIZUME-KUNZLER, DEBORAH C.; MORIYA, HENRIQUE T.; SILVA, RONALDO A.; CRUZ, JOAO C.G.; LOPES, RENAN B.; RIGHETTI, RENATO F.; VIEIRA, RODOLFO de P.; SAIKI, MITIKO ; MARTINS, MILTON A.; TIBERIO, IOLANDA de F.L.C.; ARANTES-COSTA, FERNANDA M.; SARAIVA-ROMANHOLO, BEATRIZ M.. Low dose of chlorine exposure exacerbates nasal and pulmonary allergic inflammation in mice. Scientific Reports, v. 8, n. 12636, 2018. DOI: 10.1038/s41598-018-30851-6

    Abstract: Work-exacerbated asthma (WEA) is defined as preexisting asthma that worsens with exposure to irritants [e.g., chlorine (Cl2) derivatives] in the workplace. The maximum allowable concentration in the workplace of Cl2 exposure is 3 mg/ m3 (described in OSHA). We investigated in an experimental asthma model in mice the effects of a single exposure to a sodium hypochlorite dose with this allowed chlorine concentration and a tenfold higher dose. Acute chlorine exposure at 3.3 mg/m3 in the OVA-sensitized group increased eosinophils in the peribronquial infiltrate, cytokine production, nasal mucus production and the number of iNOS positive cells in the distal lung compared to only sensitized mice. The exposure to a higher dose of 33.3 mg/m3 in the OVA-sensitized group resulted in an increase in respiratory system elastance, in the total and differential numbers of inflammatory cells in bronchoalveolar lavage fluid, IL-4, IL-5, and IL-17 in the lungs, eosinophils in peribronquial infiltrate and mucus content in nasal compared to non-exposed and sensitized animals. In this asthma model, chorine exposures at an allowable dose, contributed to the potentiation of Th2 responses. The functional alterations were associated with increased iNOS and ROCK-2 activation in the distal lung.


  • IPEN-DOC 25094

    FREIRE, LUCIANO O. ; ANDRADE, DELVONEI A. de ; MONTERRAIN, DANIEL. A system status definition to improve behavior description in specifications based on constructal law. Open Journal of Applied Sciences, v. 8, n. 8, p. 315-337, 2018. DOI: 10.4236/ojapps.2018.88024

    Abstract: System behavior description using states faces problems like state explosion, lack of clear definition of state, state identification and coordination between multiple agents. The goals of this work are to ease design activity, to reduce engineering efforts, and to mitigate project risks. The proposed way is to improve information flow during design by adding definitions and some protocols or rules for communicating a specification or design description. This work presented an objective definition of system status (way of interaction with the rest of the world) along other concepts. This work focused in definitions as mind entities and their importance to rationalize work and mitigate project risks during design. This article presented some simple examples to illustrate the advantages of each aspect of proposed definition of system status and discussed limits and exceptions for such definition. The key finding was the proposed definition which was the simplest while keeping completeness at a given product breakdown level. Such definition of status enforced formal segregation of needs and solutions, and eased the inclusion of behavior definition in specifications.


  • IPEN-DOC 25093

    FERREIRA, JOAO C. ; CAVALLARI, ROGER V. ; BERGAMASCHI, VANDERLEI S. ; ANTONIASSI, RODOLFO M. ; TEIXEIRA-NETO, ANGELA A.; LINARDI, MARCELO ; SILVA, JULIO C.M.. Palladium nanoparticles supported on mesoporous biocarbon from coconut shell for ethanol electro‑oxidation in alkaline media. Materials for Renewable and Sustainable Energy, v. 7, n. 4, 2018. DOI: 10.1007/s40243-018-0130-z

    Abstract: Palladium nanoparticles supported on carbon Vulcan XC72 (Pd/C) and biocarbon (Pd/BC) synthesized by sodium borohydride process were used as catalysts for ethanol electro-oxidation in alkaline media. The biocarbon (BC) from coconut shell with mesoporous and high surface area (792 m2 g−1) was obtained by carbonization at 900 °C and the hydrothermal treatment in a microwave oven. The D-band and G-band intensity ratio (ID/IG) from Raman analysis showed high disorder of the biocarbon, while X-ray photoelectron spectroscopy (XPS) suggests higher percentage of oxygen groups on the surface of biocarbon than of Vulcan XC72. From X-ray diffraction (XRD), it was observed peaks in 2θ degree related to the face centered cubic (fcc) structure of palladium and the mean crystallite sizes calculated based on the diffraction peak of Pd (220) were 5.6 nm for Pd/C and 5.3 nm for Pd/BC. Using Transmission Electron Microscope (TEM), it was observed particles well dispersed on both carbons support materials. The electrocatalytic activity of the materials was investigated by cyclic voltammetry (CV) and chronoamperometry (CA) experiments. The peak current density (on CV experiments) from ethanol electro-oxidation on Pd/BC was 50% higher than on Pd/C, while the current density measured at 15 min of CA experiments was 80% higher on Pd/BC than on Pd/C. The higher catalytic activity of Pd/BC might be related to the large surface area of the biocarbon (792 m2 g−1) vs (239 m2 g−1) of Vulcan carbon, the defects of the biocarbon structure and higher amount of oxygen on the surface than Carbon Vulcan XC 72.


  • IPEN-DOC 25092

    FEITOSA, SABRINA A.; CAMPOS, FERNANDA; YOSHITO, WALTER K. ; LAZAR, DOLORES R.R. ; USSUI, VALTER ; VALANDRO, LUIZ F.; BOTTINO, MARCO A.; BOTTINO, MARCO C.. Effect of the bonding strategy on the tensile retention of full-contour zirconia crowns. International Journal of Adhesion and Adhesives, v. 85, p. 106-112, 2018. DOI: 10.1016/j.ijadhadh.2018.06.006

    Abstract: This study evaluated the effect of distinct bonding strategies on the retention of full-contour zirconia ceramic (YTZP, FCZ) crowns, and it characterized some physicochemical and mechanical properties of FCZ ceramic and its corresponding glazing system. To evaluate retention strength, dies were made with a dentin-analogue material to simulate a prepared tooth. FCZ crowns were manufactured using CAD-CAM technology and allocated into groups according to the bonding strategy: no ceramic treatment (PF – Panavia F cementation), glaze (GL), tribochemical silica coating (CJ), CJ + GL, and piranha solution followed by glaze (PS + GL). The specimens were subjected to thermocycling and storage in distilled water for 100 days before the retention tests. FCZ presented a porosity volume fraction of 0.2%, an apparent density of 6.06 g/cm3, Vickers hardness of 12.4±0.07 GPa, and fracture toughness of 5.54±0.24 MPam1/2. SEM revealed a homogeneous microstructure composed of submicron-sized grains. XRD identified mainly zirconia's tetragonal phase. Glaze powder morphology was observed to be irregular, with a nanometric particle size, and a diffraction pattern characteristic of an amorphous material with several peaks of leucite. The PF and GL groups had higher retention values. The majority of the groups presented pre-test bonding failures, and two catastrophic failures of the FCZ-crown (GL and PF groups) were noted. The use of an MDP-containing resin cement or glaze application might improve retention of the FCZ crowns.


  • IPEN-DOC 25090

    FALCAO, R.B. ; DAMMANN, EDGAR D.C.C. ; ROCHA, C.J. ; DURAZZO, M. ; ICHIKAWA, R.U. ; MARTINEZ, L.G. ; BOTTA, W.J.; LEAL NETO, R.M. . An alternative route to produce easily activated nanocrystalline TiFe powder. International Journal of Hydrogen Energy, v. 43, n. 33, p. 16107-16116, 2018. DOI: 10.1016/j.ijhydene.2018.07.027

    Abstract: In this paper, an alternative process route to produce active nanocrystalline TiFe compound was investigated. First, TiH2 and Fe powders were dry co-milled in a planetary ball mill for 5e40 h. TiH2 was selected as precursor powder, instead of Ti powder, due its fragility, which has proved to be beneficial to decrease powders adherence on milling tools. In terms of loose powder mass, milling yields ranged from 90 to 95 wt.%. Next, milled powders were post-heated at 873 K under dynamic high-vacuum for TiFe synthesis reaction. First hydrogen absorption was verified in situ during the cooling process of samples (until the room temperature), being the amount of hydrogen absorbed and desorbed by this samples measured by automated Sievert's apparatus, under constant hydrogen flow rate of 9 cm3. min-1 (dynamic measurements). Besides to allowing the first absorption in situ, the investigated process route also allowed the production of the non-stoichiometric TiFe compound (rich in Ti) in samples milled for shorter times (5 and 10 h), both characteristics associated with maintaining the mechanical compound activity. Each sample absorbed hydrogen at 2 MPa during the cooling process, requiring no additional thermal activation cycles, since the samples milled for shorter times (mainly for 10 h) could absorb hydrogen for the first time more easily. However, the samples milled for longer times (25 and 40 h) shown better results in terms of reversible and storage capacities (0.73 and 0.94 wt.%, respectively).


  • IPEN-DOC 25089

    ESTEVES-PEDRO, NATALIA M.; SUGIBAYASHI, KENJI; OSTROSKY, ELISSA A.; FERRARI, MARCIO; SUFI, BIANCA da S. ; MATHOR, MONICA B. ; MORENO, PAULO R.H.; LOURENCO, FELIPE R.; CONSIGLIERI, VLADI O.; BABY, ANDRE R.; KANEKO, TELMA M.. Validation cytotoxicity assay for lipophilic substances. Current Topics in Medicinal Chemistry, v. 18, n. 4, p. 275-286, 2018. DOI: 10.2174/1568026618666180410142829

    Abstract: It is challenging to disperse lipophilic substances in a validated cytotoxicity assay, especially for compounds with log K-ow greater than or equal to 5 that may show false negative results. The purpose of this study was to explain the challenges in conducting a cytotoxicity validated test of lipophilic substances: Minthostachys setosa, Pimenta pseudocaryophyllus, and Drimysbrasiliensis essential oils. Additionally, we compared the equivalence of Neutral Red (NR) and 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl) -2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) in detecting cell viability. The Hydrophile-Lipophile Balance (HLB) technique was used to evaluate the dispersion of essential oils and cytotoxicity in accordance to the guidelines of the OECD / GD 129 validated cytotoxicity assay. We compared the equivalence of vital dyes by TOST equivalence test. According to the results, we demonstrated the possibility of using other ways to disperse the lipophilic substances. Based on the HLB theory, we selected polysorbate 20 as the best solubilizing agent of the essential oils studied in D10 culture medium


  • IPEN-DOC 25088

    DURAZZO, MICHELANGELO ; FREITAS, ARTUR C. ; SANSONE, ALBERTO E.S. ; FERREIRA, NILDEMAR A.M. ; CARVALHO, ELITA F.U. de ; RIELLA, HUMBERTO G. ; LEAL NETO, RICARDO M. . Sintering behavior of UO2-Er2O3 mixed fuel. Journal of Nuclear Materials, v. 510, p. 603-612, 2018. DOI: 10.1016/j.jnucmat.2018.08.051

    Abstract: The incorporation of burnable neutron absorbers into nuclear fuel pellets is important regarding reactivity compensation, which enables longer fuel cycles. The dry mechanical blending route is the most attractive process to accomplish absorbers incorporation because of its simplicity. By using this route, the present work has investigated the sintering behavior of UO2Er2O3 mixed fuel. A comparison with UO2Gd2O3 sintering behavior was presented. The behavior of UO2Er2O3 fuel sintering was similar to that reported for UO2Gd2O3 fuel, e.g. two-stage sintering with two peaks in the shrinkage rate curves. The effect showed to be less pronounced for Er2O3. This was attributed to the characteristics of the Er2O3 powder particles used as raw-material, whose agglomerates can be more easily broken and thus better homogenized during the blending with UO2 powder. These results confirmed that sinterability depends directly on the quality of the homogenization of the powders, as seen previously. A second phase was experimentally detected in the UO2Er2O3 system, but its impact on the sintering behavior of this mixed fuel has not yet been clarified.


  • IPEN-DOC 25087

    DONATUS, UYIME ; VIVEIROS, BARBARA V.G. de ; ALENCAR, MAICON C. de ; FERREIRA, RAPHAEL O.; MILAGRE, MARIANA X. ; COSTA, ISOLDA . Correlation between corrosion resistance, anodic hydrogen evolution and microhardness in friction stir weldment of AA2198 alloy. Materials Characterization, v. 144, p. 99-112, 2018. DOI: 10.1016/j.matchar.2018.07.004

    Abstract: Correlation between corrosion resistance, anodic hydrogen evolution and microhardness in the friction stir weldment of AA2198-T851 alloy has been investigated. Different microscopy techniques, scanning vibrating electrode technique (SVET) and potentiodynamic polarization tests were employed in the investigation. Unlike other 3rd generation Al-Cu-Li alloys where the regions that are most susceptible to corrosion are always within the weld region, the results reveal that the parent material is the most susceptible in this case. There is a direct correlation between corrosion resistance, anodic hydrogen evolution and microhardness in the weldment, and the T1 phase is associated with the direct correlation.


  • IPEN-DOC 25086

    AGUILA, A. del; SORRIBAS, M.; LYAMANI, H.; TITOS, G.; OLMO, F.J.; ARRUDA-MOREIRA, G.; YELA, M.; ALADOS-ARBOLEDAS, L.. Sources and physicochemical characteristics of submicron aerosols during three intensive campaigns in Granada (Spain). Atmospheric Research, v. 213, p. 398-410, 2018. DOI: 10.1016/j.atmosres.2018.06.004

    Abstract: Aerosol particles in the submicron range and their physicochemical characteristics were investigated for the first time in Granada, southeastern Iberian Peninsula, during three intensive campaigns. The physical and chemical characteristics were analysed during two spring campaigns and one autumn campaign. New particle formation (NPF) events were found to be more frequent in spring than in autumn. The mean duration, growth rates and maximum diameters had ranges of 5.3–13.2 h, 2.4–4.0 nm h−1 and 35–47 nm, respectively. In addition, one shrinkage event occurred and had a duration of 2.2 h and a shrinkage rate of −2.5 nm h−1. During a period of atmospheric stagnation conditions under the influence of mountain breezes, three consecutive NPF events occurred. The high frequency of the NPF events was attributed to higher temperature and radiation levels and lower relative humidity than during a previous day with similar stagnant conditions but no nucleation occurrence. According to correlation analysis, mineral components correlated with particle number in the Aitken mode, while metals and secondary inorganic aerosols correlated with particle number in the finer and larger fractions, respectively. Pollutants such as CO, NO2, NO and black carbon showed moderate and high correlations with particle number in the submicron fraction. To assess the impact of the particle number contribution according to sources, a new approach was introduced using black carbon concentrations, resulting in four major contributors: urban background, traffic, NPF and biomass burning. The proposed approach was validated by means of different models based on the aerosol spectral dependencies and chemical compositions that classify aerosol populations. Both the models and the proposed approach identified biomass burning and fossil fuel particles during the same periods, and the results showed good agreement. The proposed approach can guide future studies attempting to account for submicron particle contributions in other urban environments.


  • IPEN-DOC 25084

    DARRIBA, GERMAN N.; MUNOZ, EMILIANO L.; CARBONARI, ARTUR W. ; RENTERIA, MARIO. Experimental TDPAC and theoretical DFT study of structural, electronic, and hyperfine properties in (111In → )111Cd-doped SnO2 semiconductor: Ab initio modeling of the electron-capture-decay after-effects phenomenon. Journal of Physical Chemistry C, v. 122, n. 30, p. 17423-17436, 2018. DOI: 10.1021/acs.jpcc.8b03724

    Abstract: In this paper we investigate the effect of Cd doping at ultralow concentrations in SnO2 both experimentally, by measuring the temperature dependence of the electric quadrupole hyperfine interactions with time-differential γ–γ perturbed angular correlation (TDPAC) spectroscopy using 111Cd as probe nuclei, and theoretically, by performing first-principles calculations based on the density functional theory. TDPAC spectra were successfully analyzed with a time-dependent on–off model for the perturbation factor. These results show combined dynamic plus static interactions whose electric-field-gradients were associated in this model to different stable electronic configurations close to the Cd atoms. The dynamic regime is then originated in fast fluctuations between these different electronic configurations. First-principles calculation results show that the Cd impurity introduces a double acceptor level in the top of the valence band of the doped semiconductor and produces isotropic outward relaxations of the nearest oxygen neighbors. The variation of the calculated electric-field gradient tensor as a function of the charge state of the Cd impurity level shows an interesting behavior that explains the experimental results, giving strong support from first-principles to the electron-capture after-effects proposed scenario. The electron-capture decay of the parent 111In to 111Cd as well as the double acceptor character of the 111Cd impurity and the electric nature of the host are shown to contribute to the existence of these types of time-dependent hyperfine interactions.


  • IPEN-DOC 25083

    COUTO, C.P. ; POLITANO, R. ; GOMES, M.P. ; COLOSIO, M.A.; ROSSI, J.L. . Diffusion analyses using GDOES technique of the 22MnB5 press hardened steel with Al-Si and Zn-Ni coatings. Materials Science Forum, v. 930, p. 472-477, 2018. DOI: 10.4028/

    Abstract: The hot stamping process consists to heat the steel blank, at total austenitization temperatures and to transfer it into the press tooling for forming and fast cooling to fully martensitic transformation. This transference from furnace to press stage promotes some steel oxidation. The application of metallic coatings avoids this phenomenon. The Al-Si coating, a patented process, has been the most applied on steel. Hence, alternative coatings like Zn-Ni are under development. It is known that this furnace heating causes chemical elements diffusion that results in intermetallics formation. This study had the objective of analyze the diffusion profiles of chemical elements present in the substrate, 22MnB5 steel, and coatings of Al-Si and Zn-Ni, using glow-discharge optical emission spectroscopy - GDOES and to correlate the results with those obtained with energy dispersive X-ray spectroscopy - EDS. The results showed that for the Zn-Ni sample, the Zn and Fe profiles at the interfacial zone, are predominant; which justify the high proportion of ZnFe phases as showed using scanning electron microscopy - SEM images. For the Al-Si sample at the interfacial zone, the profile of Al and Fe varies simultaneously; besides that, silicon diffusion in the substrate is more effectively than the nickel diffusion. For this reason, it was possible to identify AlFeSi phase near to the steel substrate.


  • IPEN-DOC 25082

    COSTA, ANDREA da; ZORGI, NAHIARA E.; NASCIMENTO, NANCI do ; GALISTEO JUNIOR, ANDRES J.; ANDRADE JUNIOR, HEITOR F. de. Gamma irradiation of Toxoplasma gondii protein extract improve immune response and protection in mice models. Biomedicine & Pharmacotherapy, v. 106, p. 599-604, 2018. DOI: 10.1016/j.biopha.2018.06.155

    Abstract: Gamma radiation induces protein changes that enhance immunogenicity for venoms, used in antivenin production. Coccidian parasites exposed to gamma radiation elicit immune response with protection in mice and man, but without studies on the effect of gamma radiation in soluble acellular extracts or isolated proteins. Toxoplasmosis is a highly prevalent coccidian disease with only one vaccine for veterinary use but with remaining tissue cysts. Total parasite extracts or recombinant proteins used as immunogen induce usually low protection. Here, we study gamma radiation effect on T. gondii extracts proteins (STAG) and its induced immunity in experimental mice models. By SDS-PAGE, protein degradation is seen at high radiation doses, but at ideal dose (1500 Gy), there are preservation of the antigenicity and immunogenicity, detected by specific antibody recognition or production after mice immunization. Immunization with STAG irradiated at 1500 Gy induced significant protection in mice immunized and challenged with distinct T. gondii strains. In their blood, higher levels of specific CD19+, CD3+CD4+ and CD3+CD8+ activated cells were found when compared to mice immunized with STAG. Irradiated T. gondii tachyzoites extracts induce immune response and protection in mice in addition, could be a feasible alternative for Toxoplasma vaccine.


  • IPEN-DOC 25081

    CORDEIRO, GUILHERME L.; CAMARGO, ELAINE F. de; SANTOS, MONIQUE C.L. ; PEREIRA, CONRADO V.; USSUI, VALTER; LIMA, NELSON B. de; NETO, ALMIR O. ; LAZAR, DOLORES R.R.. Improved Pt/CeO2 electrocatalysts for ethanol electro-oxidation. International Journal of Electrochemical Science, v. 13, n. 7, p. 6388-6401, 2018. DOI: 10.20964/2018.07.58

    Abstract: A simple and low-cost approach for the preparation of wide-gap (Eg = 3.43 eV), fine cerium dioxide crystals (CeO2, d = 8.1 nm), was developed in order to support Pt nanoparticles as electrocatalysts for ethanol oxidation. Cerium oxide powders were prepared by precipitation from cerium chloride solution in ammonia medium and the influence of calcination temperature was evaluated. Platinum nanoparticles were incorporated by a wet chemical reduction of chloroplatinic acid with sodium borohydrate. Compared to a state-of-the-art Pt/C, the nanocomposite exhibited a much higher mass activity (2.5×) and significant anti-poisoning ability. The promotional effect of the CeO2 nanocrystals was discovered to be affected by heat treatment conditions. Compared to oven-dried samples, calcination allows to (i) an enhanced metal–support interaction between CeO2 and Pt and (ii) an enhancement of electron transportation to catalyst owing to the shrinkage of CeO2 bandgap, thereby promoting the oxidation of the strongly adsorbed CxHy. Therefore, the Pt/CeO2 nanocomposite appears to be a promising electrocatalyst for advanced energy conversion.


  • IPEN-DOC 25080

    CONTURBIA, G.L.C.R.; DURAZZO, M. ; CARVALHO, E.F.U. de ; RIELLA, H.G. . Phase quantification in UAlx-Al dispersion targets for Mo-99 production. Journal of Nuclear Materials, v. 509, p. 465-477, 2018. DOI: 10.1016/j.jnucmat.2018.07.029

    Abstract: Uranium aluminide (UAlx) is a mixture of three distinct intermetallic compounds comprised of UAl2, UAl3 and UAl4, where the “x” is used to denote a mixture of those phases. Usually UAlx is formed during the target fabrication process by means of a solid state reaction between the uranium aluminide and aluminum. Quantitative techniques such as image analysis and X-ray diffraction using the Rietveld method were compared for their applicability in the determination of the UAl2, UAl3 and UAl4 concentrations, both in the UAl2 primary ingot and in the UAlx-Al dispersion. The UAlx composition was quantified in all stages of the target manufacturing. The image analysis method was shown to be useful for UAlx phase quantification in the primary UAl2 ingot, but was not applicable in the case of UAlx-Al dispersions. The X-ray diffraction method allowed the quantification of the existing UAlx phases in both the primary ingot and UAlx-Al dispersions. Possible sources of error are discussed. The method of quantification based on X-ray diffraction was shown to be appropriate to monitor the evolution of UAlx phases during the manufacturing process.


  • IPEN-DOC 25079

    CHURA-CHAMBI, ROSA M. ; FRAGA, TATIANA R.; SILVA, LUDMILA B. da; YAMAMOTO, BRUNO B.; ISAAC, LOURDES; BARBOSA, ANGELA S.; MORGANTI, LIGIA . Leptospira interrogans thermolysin refolded at high pressure and alkaline pH displays proteolytic activity against complement C3. Biotechnology Reports, v. 19, n. e00266, p. 1-7, 2018. DOI: 10.1016/j.btre.2018.e00266

    Abstract: Enzymes from the thermolysin family are crucial factors in the pathogenesis of several diseases caused by bacteria and are potential targets for therapeutic interventions. Thermolysin encoded by the gene LIC13322 of the causative agent of leptospirosis, Leptospira interrogans, was shown to cleave proteins from the Complement System. However, the production of this recombinant protein using traditional refolding processes with high levels of denaturing reagents for thermolysin inclusion bodies (TL-IBs) solubilization results in poor recovery and low proteolytic activity probably due to improper refolding of the protein. Based on the assumption that leptospiral proteases play a crucial role during infection, the aim of this work was to obtain a functional recombinant thermolysin for future studies on the role of these metalloproteases on leptospiral infection. The association of high hydrostatic pressure (HHP) and alkaline pH was utilized for thermolysin refolding. Incubation of a suspension of TL-IBs at HHP and a pH of 11.0 is non-denaturing but effective for thermolysin solubilization. Soluble protein does not reaggregate by dialysis to pH 8.0. A volumetric yield of 46 mg thermolysin/L of bacterial culture and a yield of near 100% in relation to the total thermolysin present in TL-IBs were obtained. SEC-purified thermolysin suffers fragmentation, likely due to autoproteolysis and presents proteolytic activity against complement C3 α-chain, possibly by a generation of a C3b-like molecule. The proteolytic activity of thermolysin against C3 was time and dose-dependent. The experience gained in this study shall help to establish efficient HHP-based processes for refolding of bioactive proteins from IBs.


  • IPEN-DOC 25078

    CASTRO, M.C. ; SILVA, N.F. ; CALDAS, L.V.E. . Testing an extrapolation chamber in computed tomography standard beams. Journal of Physics: Conference Series, v. 975, p. 1-4, 2018. DOI: 10.1088/1742-6596/975/1/012066

    Abstract: The computed tomography (CT) is responsible for the highest dose values to the patients. Therefore, the radiation doses in this procedure must be accurate. However, there is no primary standard system for this kind of radiation beam yet. In order to search for a CT primary standard, an extrapolation ionization chamber built at the Calibration Laboratory (LCI) of the Instituto de Pesquisas Energéticas e Nucleares (IPEN), was tested in this work. The results showed to be within the international recommended limits.


  • IPEN-DOC 25077

    CASTRO, LILIANA ; MOREIRA, EDSON G. ; VASCONCELLOS, MARINA B.A. ; LANGE, CAMILA N. ; PEDRON, TATIANA; BATISTA, BRUNO L.. Stability assessment of a bovine kidney reference-material candidate. Journal of Radioanalytical and Nuclear Chemistry, v. 317, n. 2, p. 1133-1139, 2018. DOI: 10.1007/s10967-018-5928-8

    Abstract: Reference materials are used worldwide and necessary for quality control purposes during analytical determinations. The present study describes the stability evaluation of a bovine kidney reference-material candidate. An isochronous layout was performed, in which the flasks involved are exposed at different temperatures for different time periods and then are analyzed at the same time at the end of the study. The mass fractions of ten inorganic constituents were determined using instrumental neutron activation analysis and inductively coupled plasma mass spectrometry. Statistical analysis, univariate and multivariate, showed no significant differences in composition between units exposed to the different temperatures and times. The reference material may be transported under normal transportation conditions and the certified values and uncertainties will continue to be valid for a period of 2 years.


  • IPEN-DOC 25076

    CASTRO, MARCOS R. de ; MONTEIRO, WALDEMAR A. ; POLITANO, RODOLFO . Enhancements on strength of body structure due to bake hardening effect on hot stamping steel. International Journal of Advanced Manufacturing Technology, p. 1-12, 2018. DOI: 10.1007/s00170-018-2542-4

    Abstract: Body structure projects are designed to develop lightweight structures, which result in low fuel consumption and emissions for internal combustion engines and longer battery life in the case of electric vehicles. The structures need to be lightweight but also strong in order to provide maximum safety to the occupants. These premises have led to the development of special materials such as the hot stamping steels. The most used steel in this process, quenched 22MnB5, also exhibits the bake hardening effect: its yield stress increases after being exposed at temperatures close to 200 °C (typical heat treatment of paint lines in the automotive industry). The aim of this study was to verify the improvement in the mechanical strength of a body structure due to the bake hardening effect to which the hot-stamped steel componentswere submitted. Samples of annealed 22MnB5 steel were submitted to tensile and chemical analysis. A second group of the same steel was subjected to an additional heat treatment in a laboratory furnace simulating the heating that occurs in the body paint line. Subsequently, the same tests were performed with the samples from the first group. Tensile tests evidenced the increase of 6.5% in the yield stress of the samples that suffered the bake hardening effect. The stress-strain diagram curves were used as the input to the side crash simulation program. The simulations demonstrated that the body structure whose hot-stamped parts were subjected the bake hardening effect had a 2% reduction in side crash intrusion compared to body structure where the parts did not suffer this effect. In the case of the lateral protection bar test, the bake hardening effect provided a 5% increase in the maximum bending load.


  • IPEN-DOC 25075

    CASTANHEIRA, BRUNA; TRIBONI, EDUARDO R.; ANDRADE, LUANA dos S.; TRINDADE, FABIANE de J.; OTUBO, LARISSA ; TEIXEIRA, ANTONIO C.S.C.; POLITI, MARIO J.; QUEIROZ, THIAGO B. de; BROCHSZTAIN, SERGIO. Synthesis of novel periodic mesoporous organosilicas containing 1,4,5,8-Naphthalenediimides within the pore walls and their reduction to generate wall-embedded free radicals. Langmuir, v. 34, n. 28, p. 8195-8204, 2018. DOI: 10.1021/acs.langmuir.8b00220

    Abstract: Novel periodic mesoporous organosilicas (PMOs) containing 1,4,5,8-Naphthalenediimide (NDI) chromophores as an integral part of the pore walls were synthesized in acidic conditions, in the presence of inorganic tetraethyl orthosilicate, using triblock copolymer surfactant Pluronic P-123 as a template. The NDI precursor, the bridged silsesquioxane N,N′-bis(3-triethoxysilylpropyl)-1,4,5,8-naphthalenediimide, was synthesized by reaction of 1,4,5,8-naphthalenetetracarboxylic dianhydride with excess 3-aminopropyltriethoxysilane. A series of samples containing up to 19% (weight %) of NDI were prepared (the materials were labeled PMONDIs). 13C and 29Si solid-state nuclear magnetic resonance revealed that the NDI moiety was intact in the PMONDIs and efficiently grafted to the silica network. Samples with up to 16% NDI load presented an ordered two-dimensional-hexagonal mesoscopic structure, according to small-angle X-ray scattering, transmission electron microscopy, and nitrogen adsorption isotherms. Fluorescence spectra of the PMONDIs showed excimer formation upon excitation, suggesting high flexibility of the organic moieties. Reduction of PMONDIs with aqueous sodium dithionite led to the formation of wall-embedded NDI anion radicals, as observed by the appearance of new visible/near-infrared absorption bands. The PMONDIs were also shown to be efficient photocatalysts in the degradation of sulfadiazine, an antibiotic selected here as a model pollutant, which is usually present in water bodies and wastewater.


  • IPEN-DOC 25074

    CARDOSO, QUEZIA ; SILVA, FRANKS M.; VIEIRA, LIGIA S.; CASINI, JULIO C.S.; SAKATA, SOLANGE K. ; FARIA, RUBENS N. de . The production of reduced graphene oxide by a low-cost vacuum system for supercapacitor applications. Materials Science Forum, v. 930, p. 609-612, 2018. DOI: 10.4028/

    Abstract: Graphene has attracted significant interest because of its excellent electrical properties. However, a practical method for producing graphene on a large scale is yet to be developed. Graphene oxide (GO) can be partially reduced to graphene-like sheets by removing the oxygencontaining groups and recovering the conjugated structure. GO can be produced using inexpensive graphite as the raw material via cost-effective chemical methods. High vacuum and temperature (10−7 mbar and 1100°C, respectively) conditions are well-known to enable the preparation of reduced powder at the laboratory scale. However, a large-scale high vacuum reduction system that can be routinely operated at 10−7 mbar requires considerable initial capital as well as substantial operational and maintenance costs. The current study aims at developing an inexpensive method for the large-scale reduction of graphene oxide. A stainless steel vessel was evacuated to backing-pump pressure (10−2 mbar) and used to process GO at a range of temperatures. The reduction of GO powder at low vacuum pressures was attempted and investigated by X-ray diffraction and Fourier transform infrared spectroscopy. The experimental results of processing GO powder at various temperatures (200–1000°C) at relatively low pressures are reported. The microstructures of the processed materials were investigated using scanning electron microscopy and chemical microanalyses via energy dispersive X-ray analysis.


  • IPEN-DOC 25073

    CONTATORI, CHESTER ; COUTO, ANTONIO A. ; VATAVUK, JAN; BORGES, ARNALDO A.C. ; LIMA, NELSON B. de ; BALDAN, RENATO. Effect of copper and magnesium on the microstructure of centrifugally cast Al-19%Si alloys. Materials Science Forum, v. 930, p. 484-488, 2018. DOI: 10.4028/

    Abstract: Hypereutectic Al-Si alloys can be used in applications that require high wear resistance. Such wear resistance is achieved by the presence of hard primary silicon particles, allied to the formation of Mg2Si intermetallic phase when magnesium is added in this alloy. Centrifugal casting generates a gradient in the microstructure of hypereutectic Al-Si alloys that can favor such applications. Cylindrical components of Al-19%Si alloy containing added copper and magnesium contents were processed by centrifugal casting. The purpose of this study is to investigate the formation and segregation of particles of primary silicon (β) and Mg2Si in Al-19%Si alloy containing additions of copper and magnesium. Because the density of silicon (2.33 g/cm3) and Mg2Si (1.88 g/cm3) is lower than that of aluminum (2.67 g/cm3), centrifugal casting causes primary silicon (β) and Mg2Si particles to concentrate more at the outer wall of the centrifuged pipe. In this study, primary silicon (β) and Mg2Si particles were found to be retained at the outer wall of the pipe. It is believed that the rapid cooling of the molten metal in the region of contact with the mold, whose temperature is lower than that of the molten metal, allied to the centrifugal force, prevented the particles from migrating to the inner wall of the pipe. The microstructure shows a gradient in the distribution of these phases, enabling the production of a functionally graded material. The addition of copper and magnesium leads to the formation of Mg2Si and Al5Cu2Mg8Si6 phases, reducing the amount of primary β phase (Si) particles. In all the evaluated conditions, a tendency is also observed for a gradual increase in the segregation of silicon towards the inner wall along the entire length of the centrifuged pipe.


  • IPEN-DOC 25072

    CAMPOS, FABIO E. de ; PERINI, EFRAIN A. ; ZAPPAROLI JUNIOR, CARLOS L. ; CALVO, WILSON A.P. ; STAROVOITOVA, VALERIIA N.. Main steps for radiopharmaceuticals hot cells validation in accordance with GMP requirements: methodology and practical guide. Journal of Environmental Science and Engineering A, v. 7, p. 132-139, 2018. DOI: 10.17265/2162-5298/2018.03.004

    Abstract: The worldwide GMP (Good Manufacturing Practices) guidelines issued for injectable pharmaceuticals globally agree that the vials filling operation must be performed under air cleanliness Grade A. The air cleanliness classifications adopted by the WHO (World Health Organization) define the particle diameter size, the sampling occupancy state and the limit concentration of viable particles. To reach conformity regarding the microbial limits foreseen at the GMP guidelines, a microbiological monitoring program must be stablished for selected sampling points such as active air sampling, passive air sampling (settle plate method), surfaces sampling (contact method), personnel sampling (gloves and clothes), compressed gas, materials and equipment that may interfere and compromise the product microbiological quality. The key elements for a GMP certification are directly related to a qualification and validation program for radiopharmaceutical manufacturers that must be clearly defined and documented by a validation master plan, foreseen by the manufactures Quality Assurance office. This study describes each qualification step and test for DQ (Design Qualification), IQ (Installation Qualification), OQ (Operation Qualification) and PQ (Performance Qualification) that must be carried out and carefully planned when it comes to hot cells and isolator systems in accordance with the GMP requirements foreseen by international regulatory and supervisory bodies.


  • IPEN-DOC 25071

    BUENO, R.C.; MASOTTI, P.H.F. ; JUSTO, J.F.; ANDRADE, D.A. ; ROCHA, M.S. ; TORRES, W.M. ; MESQUITA, R.N. de . Two-phase flow bubble detection method applied to natural circulation system using fuzzy image processing. Nuclear Engineering and Design, v. 335, p. 255-264, 2018. DOI: 10.1016/j.nucengdes.2018.05.026

    Abstract: Natural circulation cooling systems are currently used in new nuclear reactors. Over the last decades, research in these systems has focused in the study of flow and heat transfer parameters. A particular area of interest is the estimation of two-phase flow parameters by image processing and pattern recognition using intelligent processing. Several methods have been proposed to identify objects of interest in bubbly two-phase images. Edge detection is an important task to estimate flow parameters, in which the bubbles are segmented to obtain several features, such as void fraction, area, and diameter. However, current methods face difficulties in determining those parameters in high bubble-density two-phase flow images. Here, a new edge detection method is proposed to segment bubbles in natural circulation instability images. The new method (Fuzzy Contrast Standard Deviation – FUZCON) uses Fuzzy Logic and image standard deviation estimates of locally measured contrast levels. Images were obtained through an experimental circuit made of glass, which enables imaging flow patterns of natural circulation cycles at ambient pressure. The results indicated important improvements on edge detection efficiency for high void fraction estimation on high-density two-phase flow bubble images, when compared to classical detectors, without the need to use smoothing algorithms or human intervention.


  • IPEN-DOC 25070

    BARABAS, ROBERTA de C. ; LIMA, ANA C. de S. ; SABUNDJIAN, GAIANE . A neuroscience-based methodology to identify the implicit associations of brazilian science teachers towards nuclear technology. International Journal of Development Research, v. 8, n. 6, p. 20904-20909, 2018.

    Abstract: Science, technology, and innovation play an essential role in helping countries increase the quality of life they offer their citizens. Since the discovery of nuclear fission in the 30s, the peaceful applications of nuclear technology have benefited several fields. Improved crops, preservation of food, health, environment protection and a stable supply of energy can be cited as contributions of nuclear technology for global wellbeing. Despite all benefits that result from the peaceful uses of nuclear technology, it is still addressed with prejudice. Prejudices may be explicit (conscious) or implicit (unconscious). Either explicit or implicit, prejudices interfere with individuals’ attitudes. This paper aims to assess the implicit associations of Brazilian science teachers towards nuclear technology by administering the Implicit Association Test (IAT). Identifying their implicit associations will contribute for the understanding of prejudices that may interfere with their teaching. A pretest with nuclear specialists was administered to check the consistency of the IAT. Subsequently, it was administered to the science teachers. The results of the IAT demonstrated more positive associations towards oil. The next step consists of proposing a methodology to change implicit associations of Brazilian science teachers towards nuclear technology.


  • IPEN-DOC 25069

    BORTOLETTO, DAIANA R.; LIMA, CASSIO A. ; ZEZELL, DENISE ; SATO, ERIKA T.; MARTINHO, H.. Vibrational spectra calculation of squamous cell carcinoma in the amide band region. Vibrational Spectroscopy, v. 97, p. 135-139, 2018. DOI: 10.1016/j.vibspec.2018.06.007

    Abstract: Alterations in the amide (1500–1700 cm−1) spectral region probed by Fourier-transform infrared spectroscopy (FTIR) have been reported comparing tumor and normal tissues. Usually, bands in this range are assigned to the so-called Amide I, II, and III vibrations which provide pieces of information concerning peptide bonds and secondary structure (α-helix, β-sheet) of proteins. Proteins folding changes due to tumoral process are usually considered to qualitatively explain the observed differences between tumor and normal tissues. In this paper, the observed changes in the FTIR spectra of squamous cell carcinoma compared to normal tissues were analyzed by First-Principles Density Functional Theory vibrational calculations. Computational models for skin and prototype β-sheet model were employed. Our findings shown that predominates conjugated Amide I + Amide II, Amide V, methylene torsions, and ring side chains torsions and swings vibrations in this region. We also notice the lack of evidence concerning changes in the secondary structure of the β-sheet peptidic model to explain the spectral differences. In fact, we concluded that the proline amino acid has the main rule to explain the data in this region being it responsible for the strong coupling between vibrations instead of water.


  • IPEN-DOC 25068

    BORRELY, S.I. ; GARCIA, V.S.G. ; BORRELY, T.; FAVARO, D.I.T. . Metals, trace elements and ecotoxicity in sediments of the Cubatão River, Brazil. Ecotoxicology and Environmental Contamination, v. 13, n. 2, p. 49-61, 2018. DOI: 10.5132/eec.2018.02.07

    Abstract: The Cubatão River is one of the most important waterways of the coast of São Paulo. The continuous discharge of domestic and industrial effluents into the river and its tributaries resulted in loss of water quality across the system. Industrial and domestic landfills are also located around the studied area. The purpose of this study was to assess two aspects of sediments from the river and two of its tributaries (Perequê and Pilões Rivers): presence of trace elements and toxic metals, and ecotoxicity. Four sampling surveys were conducted from 2010 to 2011 on six different sites (here named P0, P2, P4, P5, P7 and P8). Ecotoxicity was assessed by exposing Hyalella azteca to the collected sediments. Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectrometry (GF AAS and CV AAS) techniques were applied for measuring concentration of metals and trace elements. The latter enabled quantification of Cd, Pb and Hg, while the former enabled quantification of a wide range of metals and trace elements. As, Cr and Zn concentrations obtained by INAA as well as AAS results were compared to threshold effect levels (TEL) and probable effect levels (PEL), the sediment quality guidelines proposed by the Canadian Council of Ministers of the Environment (CCME) for evaluating the potential effects on aquatic organisms. Cd and Hg values did not exceed TEL at the most of samples. Pb exceeded TEL at only one site campaign. As, Cr and Zn values exceeded TEL in most of sampling sites, with P2 and P4 showing the highest concentrations. Enrichment Factor (EF) and Geoaccumulation Index (IGeo) were calculated for the elements determined by INAA using North American Shale Composite (NASC) and regional background values. In short, As, Br, Cr, Hf, Pb, Sb and Zn were the elements found in concerning amounts, especially As, Br, Cr and Zn. Toxicity results revealed toxic effects on sediments from P2 and P5 (mortality > 50%). Body size analysis demonstrated negative effects at P4 (length smaller than 2,500.00 μm). Data crossing analyses indicate As and Br as main possible contributors to high toxicity levels.


  • IPEN-DOC 25067

    BORGES, EDUARDO M. ; SABUNDJIAN, GAIANE ; CONTI, THADEU das N. ; BRAZ FILHO, FRANCISCO A.; GUIMARAES, LAMARTINE N.F.. Simulação de um SBLOCA em Angra 2 com o RELAP5 / RELAP5 simulation of the SBLOCA in Angra 2. Ciência, Tecnologia & Ambiente, v. 7, n. 1, 2018. DOI: 10.4322/2359-6643.07102

    Abstract: O objetivo deste trabalho foi simular e avaliar o acidente básico de projeto de perda de refrigerante por pequena ruptura de 50 cm2 na perna fria do circuito primário da usina nuclear Angra 2. Nesta simulação, verificou-se que as lógicas de atuação do Sistema de Proteção do Reator (SPR) e do Sistema de Resfriamento de Emergência do Núcleo (SREN) de Angra 2 utilizadas nesta simulação funcionaram corretamente, mantendo a integridade do núcleo com temperaturas aceitáveis durante todo o evento. Os resultados obtidos foram satisfatórios quando comparados com os apresentados pelo Relatório Final de Análise de Segurança de Angra 2 (FSAR/A2).


  • IPEN-DOC 25066

    BORGES, CARLA R.; SAMAD, RICARDO E. ; GONCALVES, KARINA de O.; VIEIRA, DANIEL P. ; COURROL, LILIA C.. Interaction between protoporphyrin IX and tryptophan silver nanoparticles. Journal of Nanoparticle Research, v. 20, n. 6, 2018. DOI: 10.1007/s11051-018-4269-4

    Abstract: Silver nanoparticles (AgNPs) have been intensively studied for several purposes including therapeutic applications in cancer. When prepared with tryptophan and photoreduction, silver nanoparticles (TrpAgNPs) become an alternative to conventional anticancer drugs. In this study, the anticancer activity of synthesized TrpAgNPs against MCF-7 breast cancer cells was evaluated, and the inhibitory concentration (IC50) was found to be ~3.4 mg/mL. Since the protoporphyrin IX (PPIX) concentrations in tumor cells are elevate compared to normal cells, the PPIX-TrpAgNP interaction was studied to investigate if it could contribute for cell apoptosis. The investigation was performed using PPIX solution (0.9 μg/mL) with different TrpAgNP concentrations (from 0 to 13 mg/mL). PPIX was characterized by UV-Vis spectroscopy, steady-state and time-resolved fluorescence spectroscopy. The results have shown that the presence of spherical TrpAgNps with 16-nm diameter quench the PPIX fluorescence intensity. This quenching is strongly dependent on the concentration of the TrpAgNPs, and it is caused by a combination of a static and a dynamic process. The chemical binding leads to oxidation of tryptophan and formation of kynurenine, observed in the emission spectra around 470 nm. The strong reduction of the PPIX fluorescence decay lifetime with nanoparticle increasing concentration confirms the quenching processes due to charge transfer from the excited PPIX states to the resonant silver states. The present study confirms the anticancer activity of TrpAgNPs on the human breast cancer cell line (MCF-7) in vitro and indicates that PPIX-AgNP interaction could contribute with MCF-7 apoptosis.


  • IPEN-DOC 25065

    BORGES, ARNALDO A.C. ; ARAUJO, MAYARA C. de ; COUTO, ANTONIO A. ; LIMA, NELSON B. de ; CONTATORI, CHESTER . Evaluation of the residual stress and microstructure of extruded and shot peened aluminum alloy 6082. Materials Science Forum, v. 930, p. 507-512, 2018. DOI: 10.4028/

    Abstract: Aluminum-magnesium-silicon alloys have been widely used as extruded products due to its mechanical strength and high ductility. The effects induced by shot peening has been extensively used in materials that have potential for structural applications. In this context, the purpose of this study was to evaluate the residual stress induced by shot peening of extruded aluminum alloy 6082. Initially, the effect of heat treatments such as solution treatment and ageing of this alloy was studied. The residual stress measurements were carried out using x-ray diffraction. The microstructure of the alloy was studied by optical microscopy. The crystallographic texture was determined using x-ray diffraction and back-scattered electron diffraction. The heat treatment sequence that resulted in the highest hardness of Al alloy 6082 was solution treatment at 560ºC for 30 min, followed by ageing at 185ºC for 5 h. The residual stress in compression of the extruded alloy’s surface increased by 87.38%, from -66.6 to -124.8 MPa, caused by shot peening. The residual stress profile indicated an increase in its value up to a depth of 86 μm, beyond which the values obtained were unreliable. The extruded section revealed accentuated crystallographic texture in the (111) plane parallel to the cross-section and in the (200) and (220) planes oriented preferentially in the longitudinal direction to extrusion and perpendicular to the (111) plane.


  • IPEN-DOC 25064

    BORDON, ISABELLA C.; EMERENCIANO, ANDREWS K.; MELO, JULIA R.C.; SILVA, JOSE R.M.C. da; FAVARO, DEBORAH I.T. ; GUSSO-CHOUERI, PALOMA K.; CAMPOS, BRUNO G. de; ABESSA, DENIS M. de S.. Implications on the Pb bioaccumulation and metallothionein levels due to dietary and waterborne exposures: the Callinectes danae case. Ecotoxicology and Environmental Safety, v. 162, p. 415-422, 2018. DOI: 10.1016/j.ecoenv.2018.07.014

    Abstract: This study aimed to assess the bioaccumulation of Pb and induction of metallothionein-like proteins (MT) in Callinectes danae through single and combined dietary and waterborne exposures. Male C. danae individuals were collected in the south area of the Cananéia-Iguape-Peruíbe Protected Area (APA-CIP), in São Paulo State, Brazil. After an acclimatization period, exposure assays were performed during 7 and 14 days, at two Pb concentrations (0.5 e 2.0 µg/g) in 4 treatments: 1) control; 2) contaminated water only; 3) contaminated food only; 4) contaminated water and food. The results indicate that C. danae is highly tolerant to Pb exposure at the evaluated concentrations. In gills, Pb bioaccumulation is more dependent of water efflux and time of exposure (higher Pb values). However, pathways act simultaneously in the induction of MT expression in this tissue. The decreases in Pb accumulation in the combined treatments and MT increases after 14 days in gills suggests that these proteins play a detoxification function in the presence of Pb. In hepatopancreas, depending on the predominance of a certain pathway or combined pathways, accumulation occured at different times. For muscle tissue, bioaccumulation was observed due to contaminated water exposure, but not dietary exposure, probably because Pb concentrations were low.


  • IPEN-DOC 25063

    BORBOREMA, SAMANTA E.T. ; OSSO JUNIOR, JOAO A. ; TEMPONE, ANDRE G.; ANDRADE JUNIOR, HEITOR F. de; NASCIMENTO, NANCI do . Pharmacokinetic of meglumine antimoniate encapsulated in phosphatidylserine-liposomes in mice model: a candidate formulation for visceral leishmaniasis. Biomedicine & Pharmacotherapy, v. 103, p. 1609-1616, 2018. DOI: 10.1016/j.biopha.2018.05.004

    Abstract: Visceral leishmaniasis (VL) is a fatal parasitic disease caused by the protozoan Leishmania spp. Meglumine antimoniate (MA) is the main treatment and has demonstrated a promising efficacy in a VL-model when encapsulated into negatively charged liposomes. Considering the current concept for the evaluation of pharmacokinetic parameters at early phases of drug discovery, we developed a formulation of MA-encapsulated into phosphatidylserine liposomes (MA-LP) and analyzed the in vitro antileishmanial activity, physicochemical properties, and pharmacokinetic profile in a mice model. The liposomal formulation had an internal mean diameter of 114 nm and a high stability in plasma. MA-LP was 23-fold more in vitro effective against Leishmania infantum-infected macrophages than the free drug, with a selectivity index higher than 220. The pharmacokinetic studies demonstrated that the liposomes increased the uptake of the drug by the liver and spleen and promoted sustained levels. MA-LP was first eliminated through renal excretion, followed by biliary excretion. In the blood, MA-LP followed a biexponential open model. This work emphasizes the importance of liposomes as potential drug delivery systems for visceral leishmaniasis.


  • IPEN-DOC 25062

    BEZERRA, S.J.C.; TREVISAN, L.R.; VIANA, I.E.L.; LOPES, R.M.; PEREIRA, D.L. ; ARANHA, A.C.C.; SCARAMUCCI, TAIS. Er,Cr:YSGG laser associated with acidulated phosphate fluoride gel (1.23% F) for prevention and control of dentin erosion progression. Lasers in Medical Science, p. 1-7, 2018. DOI: 10.1007/s10103-018-2609-3

    Abstract: To evaluate the effect of Er,Cr:YSGG laser, associated with fluoride application, on the prevention/control of dentin erosion. Dentin slabs were embedded in acrylic resin, flattened, and polished. Half of the specimens were previously eroded (10 min immersion in 1% citric acid solution) and half were kept sound. The specimens (n = 10 each substrate) were randomly allocated into the experimental groups, according to the following treatments: control (no treatment); APF gel (1.23% F, 1 min); Er,Cr:YSGG laser irradiation (P1: 0.25W, 20 Hz, 2.8 J/cm2, tip S75, beam diameter of 750 μm, 1mmaway fromthe surface); Er,Cr:YSGG laser irradiation (P2: 0.50W, 20 Hz, 5.7 J/cm2, tip S75, beam diameter of 750 μm, 1 mm away from the surface); APF gel + Er,Cr:YSGG laser P1 and; APF gel + Er,Cr:YSGG laser P2. Afterwards, the specimens underwent an erosion-remineralization cycling, consisting of a 5-min immersion into 0.3% citric acid, followed by 60-min exposure to artificial saliva. This procedure was repeated 4×/day, for 5 days. Surface loss (SL, in μm) was determined by optical profilometry. Specimens from each group were analyzed by environmental scanning electron microscopy (n = 3). Data were statistically analyzed (α = 0.05). For the eroded specimens, APF gel presented the lowest SL, being different from the control. For the sound specimens, none of the groups differed from the control, except for Er,Cr:YSGG laser P2, which presented the highest SL.When substrates were compared, only the eroded specimens of the control and APF + Er,Cr:YSGG laser P1 Groups showed higher SL. Selective structure removal was observed for the laser-treated groups. None of the Er,Cr:YSGG laser parameters were effective in the prevention/control dentin erosion. The laser was also unable to enhance the protection of fluoride against dentin erosion.


  • IPEN-DOC 25061

    BETINI, EVANDRO G. ; GOMES, MAURILIO P. ; MUCSI, CRISTIANO S. ; LUZ, TEMISTOCLES de S.; ORLANDO, MARCOS T.D.; ROSSI, JESUALDO L. . Study of the thermal diffusivity variation in thin duplex steel plates welded by GTAW process. Materials Science Forum, v. 930, p. 460-465, 2018. DOI: 10.4028/

    Abstract: This study describes the thermal diffusivity of thin duplex steel plates in the thickness direction measured using the laser-flash method after welding. The work reports the experimental efforts in recording temperature profiles of the grade UNS S32304 duplex steel during autogenous welding. The butt weld autogenous joints were carried out by the GTAW (gas tungsten arc welding) process with either argon or argon - 2% nitrogen atmospheres. The amount of nitrogen in the heat affected regions, after welding, was measured and correlated with the variation of the thermal diffusivity of the studied material. The temperature profiles were obtained using k-type thermocouples connected to a digital data acquisition system. Different thermal cycles and thermal diffusivity values were observed in the heat-affected zone (HAZ) for both samples. In the solidified zone (SZ) was observed similar increase of the thermal diffusivity values for the plates welded with pure argon and argon plus nitrogen atmosphere.


  • IPEN-DOC 25060

    BERTOLETE, M.; BARBOSA, P.A.; MACHADO, A.R.; SAMAD, R.E. ; VIEIRA JUNIOR, N.D. ; VILAR, R.; ROSSI, W. de . Effects of texturing the rake surfaces of cemented tungsten carbide tools by ultrashort laser pulses in machining of martensitic stainless steel. International Journal of Advanced Manufacturing Technology, v. 98, n. 9-12, p. 2653-2664, 2018. DOI: 10.1007/s00170-018-2407-x

    Abstract: The present study investigates the effect of texturing the rake face of uncoated cemented tungsten carbide tools by ultrashort laser pulses for tribological improvement. In this sense, four parallel micro-groove texturing patterns were created on the rake face of the cutting tools, beginning at a variable distance from the cutting edge. The pitch between grooves was also varied. Friction force, machining force, chip features, and surface roughness were evaluated from semi-orthogonal dry turning in the reference (nontextured) and textured tools. The results showed friction force reduction by nearly 40%; chip deformation decrease around 21%; machining force reduction by 20%; and surface roughness by 46 and 28% for Ra and Rz, respectively, for the best texturing pattern.


  • IPEN-DOC 25053

    BELLEZZO, MURILLO ; FONSECA, GABRIEL P.; VERRIJSSEN, AN-SOFIE; VONCKEN, ROBERT; BOSCH, MICHIEL R.V. den; YORIYAZ, HELIO ; RENIERS, BRIGITTE; BERBEE, MAAIKE; LIMBERGEN, EVERT J.V.; VERHAEGEN, FRANK. A novel rectal applicator for contact radiotherapy with HDR 192Ir sources. Brachytherapy, v. 17, n. 6, p. 1037-1044, 2018. DOI: 10.1016/j.brachy.2018.07.012

    Abstract: PURPOSE: Dose escalation to rectal tumors leads to higher complete response rates and may thereby enable omission of surgery. Important advantages of endoluminal boosting techniques include the possibility to apply a more selective/localized boost than using external beam radiotherapy. A novel brachytherapy (BT) rectal applicator with lateral shielding was designed to be used with a rectoscope for eye-guided positioning to deliver a dose distribution similar to the one of contact x-ray radiotherapy devices, using commonly available high-dose-rate 192Ir BT sources. METHODS AND MATERIALS: A cylindrical multichannel BT applicator with lateral shielding was designed by Monte Carlo modeling, validated experimentally with film dosimetry and compared with results found in the literature for the Papillon 50 (P50) contact x-ray radiotherapy device regarding rectoscope dimensions, radiation beam shape, dose fall-off, and treatment time. RESULTS: The multichannel applicator designed is able to deliver 30 Gy under 13 min with a 20350 U (5 Ci) source. The use of multiple channels and lateral shielding provide a uniform circular treatment surface with 22 mm in diameter. The resulting dose fall-off is slightly steeper (maximum difference of 5%) than the one generated by the P50 device with the 22 mm applicator. CONCLUSIONS: A novel multichannel rectal applicator for contact radiotherapy with high-doserate 192Ir sources that can be integrated with commercially available treatment planning systems was designed to produce a dose distribution similar to the one obtained by the P50 device.


  • IPEN-DOC 25057

    BARDELLA, FERNANDO ; MORAES, RAFAEL C. de; SARINGELOS, THANOS; KARATZAFERIS, ALEXANDROS; RODRIGUES, ANDRE M. ; SILVA, ANDRE G. da ; LEAL NETO, RICARDO M. . Architecting 3D interactive educational applications for the web: the case study of crystalwalk. Multimodal Technologies and Interaction, v. 2, n. 3, p. 1-12, 2018. DOI: 10.3390/mti2030056

    Abstract: This paper describes the technical development of CrystalWalk, a crystal editor and visualization software designed for teaching materials science and engineering aiming to provide an accessible and interactive platform to students, professors and researchers. Justified by the lack of proper didactic tools, an evaluation of the existing crystallographic software has further shown opportunities for the development of a new software, more focused on the educational approach. CrystalWalk’s was guided by principles of free software, accessibility and democratization of knowledge, which was reflected in the application’s architecture strategy and the adoption of state-of-the-art technologies for the development of interactive web applications, such as HTML5/WebGL, service-oriented architecture (SOA) and responsive, resilient and elastic distributed systems. CrystalWalk’s architecture was successful in supporting the implementation of all specified software requirements proposed by state-of-the-art research and deemed to exert a positive impact in building accessible 3D interactive educational applications for the web.


  • IPEN-DOC 25059

    AZEVEDO, MARIANGELA de B.M. de ; MELO, VITOR H.S. de ; SOARES, CARLOS R.J. ; MIYAMOTO, DOUGLAS M. ; KATAYAMA, RICARDO A. ; SQUAIR, PETERSON L. ; BARROS, CAIO H.N.; TASIC, LJUBICA. Development and characterization of polymeric microparticle of poly(D,L-lactic acid) loaded with holmium acetylacetonate. Journal of Microencapsulation: micro and nano carriers, v. 35, n. 3, p. 281-291, 2018. DOI: 10.1080/02652048.2018.1477843

    Abstract: Biodegradable polymers containing radioactive isotopes such as Holmium 166 (166Ho) have potential applications as beta particle emitters in tumour tissues. It is also a gamma ray emitter, allowing nuclear imaging of any tissue to be acquired. It is frequently used in the form of complexes such as holmium acetylacetonate (HoAcAc), which may cause damages in tissues next to the targets cancer cells, as it is difficult to control its linkage or healthy tissues radiotherapy effects. Poly(d,l-lactic acid), PDLLA, was used to encapsulate holmium acetylacetonate (HoAcAc) using an emulsion solvent extraction/evaporation technique. Microspheres with sizes between 20-53 µm were extensively characterised. HoAcAc release from the microspheres was assessed through studies using Inductively Coupled Plasma – Optical Emission Spectroscopy, and the microspheres showed no holmium leakage after a period of 10 half-lives and following gamma irradiation. Thus, HoAcAc loaded microspheres are here presented as a potential system for brachytherapy and imaging purposes.


  • IPEN-DOC 25058

    ARANHA, L.C. ; MUCSI, C.S. ; CEONI, F.C. ; ALENCAR, M.C. ; ROSSI, J.L. . Development of a microtorquemeter for the evaluation of the implant abutment interface behavior. Materials Science Forum, v. 930, p. 520-525, 2018. DOI: 10.4028/

    Abstract: This paper presents the initial developments of a prototype device intended to perform measurements of the fastening torque in the range bellow 1 N.m – hereby denominated microtorque. The device is intended to yield data for analysis of in vitro torquing and detorquing experiments, for fixation and removing of abutments in dental implants and implants in artificial bones. The analysis of the data acquired allowed the authors to observe characteristic fingerprints or signal signatures associated to the type of abutment or implant under experimentation as well as of the mechanical prototype characteristics. In this paper, two different systems of abutment and implant were analyzed. The correlation between the phenomena associated to the signal fingerprints indicate that the developed measurement protocol may be extended to other implant / abutment systems. The authors suggest that the insertion and removal torque curves evaluated in this study would facilitated the correlation between the abutments stability in actual patients and the dynamical behavior under masticatory function.


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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, .

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).



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.