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  • IPEN-DOC 27147

    SOUZA, A.P.S.; OLIVEIRA, L.P. de; YOKAICHIYA, F.; GENEZINI, F.A. ; FRANCO, M.K.K.D. . Neutron Guide Building instruments of the Brazilian Multipurpose Reactor (RMB) project. Journal of Instrumentation, v. 15, n. 4, p. 1-24, 2020. DOI: 10.1088/1748-0221/15/04/P04011

    Abstract: A growing community of scientists has been using neutrons in the most diverse areas of science. In order to meet the researchers demand in the areas of physics, chemistry, materials sciences, engineering, cultural heritage, biology and earth sciences, the Brazilian Multipurpose Reactor (RMB) will provide 3 thermal guides and 3 cold guides, with the installation of several instruments for materials characterization. In this study, we present a standard design requirement of two primordial instruments, namely Sabiá and Araponga. They are, respectively, cold and thermal neutron instruments and correspond to a Small-Angle Neutron Scattering (SANS) and High-Resolution Powder Neutron Diffractometer (HRPND) to be installed in the Neutron Guide Building (N02) of RMB. To provide adequate flux for both instruments, we propose here an initial investigation of the use of simple and split guides to transport neutron beams to two different instruments on the same guide. For this purpose, we use Monte Carlo simulations utilizing McStas software to check the efficiency of thermal neutron transport for different basic configuration and sources. By considering these results, it is possible to conclude that the split guide configuration is, in most cases, more efficient than cases that use transmitted neutron beams independently of source. We also verify that the employment of different coating indexes for concave and convex surfaces on curved guides is crucial, at least on simulated cases, to optimise neutron flux (intensity and divergence) and diminish facility installation cost.

    Palavras-Chave: neutron guides; neutron sources; neutron transport; rmb reactor; buildings; cold neutrons; thermal neutrons; reactor instrumentation; simulators; small angle scattering; neutron diffraction; scattering; monte carlo method


  • IPEN-DOC 27146

    OLIVEIRA, L.P. de; SOUZA, A.P.S.; YOKAICHIYA, F.; GENEZINI, F.A. ; FRANCO, M.K.K.D. . Monte Carlo simulations of the S-shaped neutron guide. Journal of Instrumentation, v. 15, n. 1, p. 1-14, 2020. DOI: 10.1088/1748-0221/15/01/P01012

    Abstract: Neutron transport along guides is governed by the Liouville theorem and the technology involved has advanced in recent decades. Computer simulations have proven to be useful tools in the design and conception of neutron guide systems in facilities. In this study, we use a Monte Carlo method to perform simulations for an S-shaped neutron guide with different dimensions for a Small-Angle Neutron Scattering (SANS) instrument, through the MCSTAS software. Awavelength cutoff is observed and shown to be dependent on the geometrical parameters of the guide. Results for the neutron flux at sample position are presented and greater sensitivity of cutoffs concerning the curvatures of the guides than to their lengths is noticed. Our results are in agreement with those obtained from the Acceptance Diagram method and we analyse the beam divergence behaviour along the S-shaped guide.

    Palavras-Chave: monte carlo method; neutron guides; neutron sources; simulation; computerized simulation; computer calculations; shape; neutron transport; small angle scattering; computer codes


  • IPEN-DOC 27145

    MONTEIRO, LUCILENA R. ; LANGE, CAMILA N.; FREIRE, BRUNA M.; PEDRON, TATIANA; SILVA, JULIO J.C. da; MAGALHÃES JUNIOR, ARIANO M. de; PEGORARO, CAMILA; BUSANELLO, CARLOS; BATISTA, BRUNO L.. Inter- and intra-variability in the mineral content of rice varieties grown in various microclimatic regions of southern Brazil. Journal of Food Composition and Analysis, v. 92, p. 1-11, 2020. DOI: 10.1016/j.jfca.2020.103535

    Abstract: The most common goal for rice breeding is to improve the nutritional content and to reduce toxic components. Fourteen varieties of rice were grown for this purpose in six microclimatic regions in southern Brazil. The elemental composition of rice and As-Species were measured by ICP-MS and HPLC-ICP-MS, respectively. Intraand inter-species variations of essential and non-essential elements in husked grains from an important riceproducing region in Brazil are presented. Arsenic, Cd, Co, Cu, Fe, Mg, Mn, Ni, Se, and Zn were significantly affected by the microclimatic region and the rice varieties. The only exception observed was the effect of Pb variety selection, with 35.4 % associated with random fluctuations. Varieties with both higher levels of Fe/Zn and lower levels of As/Cd were identified in all regions studied. All regions and varieties were able to produce rice with Cd<10 μg kg−1, but the Santa Vitoria do Palmar region where varieties with Cd<45 μg kg−1 were selected. Well-established varieties result in a higher daily intake of essential elements than the varieties under development. Therefore, our findings may provide information to support the selection procedures for varieties, as well as to encourage improvements in management practices between regions.

    Palavras-Chave: rice; food; safety; safety analysis; arsenic; elements; cadmium; intake; nutrients; chemical composition; microclimates; cultivation; geologic structures; soils


  • IPEN-DOC 27144

    ARAUJO, LEANDRO G. de ; PRADO, EDUARDO S.P. ; MIRANDA, FELIPE de S.; VICENTE, ROBERTO ; SILVA SOBRINHO, ARGEMIRO S. da; PETRACONI FILHO, GILBERTO; MARUMO, JULIO T. . Physicochemical modifications of radioactive oil sludge by ozone treatment. Journal of Environmental Chemical Engineering, v. 8, n. 5, p. 1-8, 2020. DOI: 10.1016/j.jece.2020.104128

    Abstract: An experimental study on the degradation of organic compounds from radioactive oil sludge by the ozonation process is presented. The effects of different concentrations of ozone in the oil sludge degradation over time were investigated. The experiments were performed in a 0.125 L glass reactor with magnetic stirring and a diffuser plate at the bottom to feed the ozone. The ozone concentration varied from 13 to 53 mg L−1 and the total interaction time was 1 h. To investigate the physicochemical properties of the oil sludge (solid and liquid components) prior to and after the treatment, multiple analytical characterization methods were used: Thermal Gravimetric Analysis, X-ray diffraction, Scanning Electron Microscopy coupled with Energy-Dispersive X-ray Spectroscopy, Fourier Transform Infrared spectroscopy, Spectrophotometer, and Residual Gas Analyzer. The most perceptive change is in the color of the liquid medium turned from dark brown to light yellow, especially under ozone concentrations higher than 33 mg L−1. Absorbance values decreased about 3.5 times after 30 min of treatment with [O3] =53 mg L−1. FTIR spectroscopy showed that the bands associated with the CH3 and CeH in CH2 disappeared during treatment. On the other hand, a greater presence of C]C aromatics was observed. By residual gas analysis, various organic and inorganic gases were identified during the treatment, such as CH4, H2, CO2, and H2S. Finally, the ozonation of the oil sludge proved to be effective, due to its high reaction capacity.

    Palavras-Chave: ozone; therapy; ozonization; radioactivity; sludges; oxidation; naturally occurring radioactive materials; fourier transformation; thermal gravimetric analysis


  • IPEN-DOC 27143

    MATOS, B.R. . The genuine ac-to-dc proton conductivity crossover of nafion and polymer dielectric relaxations as a fuel cell polarization loss. Journal of Electroanalytical Chemistry, v. 871, p. 1-13, 2020. DOI: 10.1016/j.jelechem.2020.114357

    Abstract: The non-ohmic behavior of Nafion electrical properties, i. e., the thickness and potential dependent conductivity, was studied in the impedance, dielectric and conductivity representations with the use of a special through-plane sampleholder in a 4-probe array. Such measurements allowed identifying the genuine ac-to-dc conductivity crossover frequency in Nafion, which occurs for f<10-1 Hz. In addition, the minimization of the interfacial electrode/ionomer polarizations with the 4-probe setup permitted the determination of the bulk dc conductivity and dielectric constant of Nafion, which are σ~0.03 Scm-1 and ε′~106 (T=40 °Cand RH=100%), respectively. The colossal dielectric constant is shown to increase the Debye length of the electric double layer to values comparable to the membrane thickness. Therefore, the exponential increase of the proton conductivity with increasing both membrane thickness and electric potential are a result of canceling out the non-linear effects of electric double layer caused by the high dielectric permittivity of Nafion. The ac-to-dc conductivity crossover in H2/O2 fuel cell impedance curves takes place for f<100 Hz and matches with the ex situ impedance spectroscopy study in excellent agreement, revealing a striking result: the potential dependent conductivity of Nafion requires extra fuel cell overpotential to overcome the electrode/ionomer interfacial polarization representing an additional polarization loss to polymer electrolyte fuel cells.

    Palavras-Chave: ionic conductivity; electric conductivity; electrical properties; fuel cells; electric fields; layers; dielectric properties; electrical properties; nonlinear problems; nmr imaging; spectroscopy


  • IPEN-DOC 27142

    SANTOS, M.C.L. ; GODOI, C.M. ; KANG, H.S.; SOUZA, R.F.B. de ; RAMOS, A.S.; ANTOLINI, E.; NETO, A.O. . Effect of Ni content in PdNi/C anode catalysts on power and methanol co-generation in alkaline direct methane fuel cell type. Journal of Colloid and Interface Science, v. 578, p. 390-401, 2020. DOI: 10.1016/j.jcis.2020.06.017

    Abstract: PdNi electrocatalysts supported on carbon were used as anode materials for methane oxidation in alkaline direct methane fuel cells (ADMEFCs). The electrocatalysts were successfully synthesized by the NaBH4 reduction method. X-ray diffraction measurements showed the formation of non-alloyed Pd in the face- centered cubic (FCC) structure for all materials and formation of NiO and Ni(OH)2 species. TEM images showed that the metal particles are well dispersed on the support with small agglomeration regions. Information about the surface structure of the catalyst were obtained by Raman spectra, mainly confirming the presence of Ni(OH)2. The species observed by DEMS, that is, methanol (m/z = 32), CO2 (m/ z = 44) and potassium formate (m/z = 84) were confirmed by FTIR, which also showed the presence of a high amount of carbonate in the methane oxidation products of the ADMEFC with Pd50Ni50/C as the anode catalyst. Tests in ADMEFCs showed that the dependence of the maximum power density on nickel content in the catalysts goes through a maximum value of 13.5 lW cm 2 at 50 at% Ni. Moreover, the amount of produced methanol decreases with increasing Ni content in the PdNi/C catalysts. Both these results can be explained by the enhanced methanol oxidation in the presence of nickel.

    Palavras-Chave: electrocatalysts; fcc lattices; methane; nickel; palladium; methanol; fuel cells; direct methanol fuel cells; alkaline electrolyte fuel cells; greenhouse gases


  • IPEN-DOC 27141

    AMARAL, MARCELLO M.; DEL-VALLE, MATHEUS; RAELE, MARCUS P. ; DE PRETTO, LUCAS R. ; ANA, PATRICIA A.. Osteoporosis evaluation through full developed speckle imaging. Journal of Biophotonics, v. 13, n. 7, p. 1-9, 2020. DOI: 10.1002/jbio.202000025

    Abstract: Osteoporosis is a disease characterized by bone mineral density reduction, weakening the bone structure. Its diagnosis is performed using ionizing radiation, increasing health risk. Optical techniques are safer, due to non-ionizing radiation use, but limited to the analyses of bone tissue. This limitation may be circumvented in the oral cavity. In this work we explored the use of laser speckle imaging (LSI) to differentiate the sound and osteoporotic maxilla andmandible bones in an in vitro model. Osteoporosis lesions were simulated with acid attack. The samples were evaluated by optical profilometry and LSI, using a custom software. Two image parameters were evaluated, speckle contrast ration and patches ratio. With the speckle contrast ratio, it was possible to differentiate sound from osteoporotic tissue. From speckle patches ratio it was observed a negative correlation with the roughness parameter. LSI is a promissory technique for assessment of osteoporosis lesions on alveolar bone.

    Palavras-Chave: osteoporosis; lasers; images; laser radiation; skeleton; bone tissues; diagnosis; optical properties; ionizing radiations; bone mineral density; statistical models; statistical models


  • IPEN-DOC 27139

    TORRES, LARISSA H.; REAL, CAROLINE C.; TURATO, WALTER M.; SPELTA, LÍDIA W.; DURÃO, ANA C.C. dos S.; ANDRIOLI, TATIANA C.; POZZO, LORENA ; SQUAIR, PETERSON L. ; PISTIS, MARCO; FARIA, DANIELE de P.; MARCOURAKIS, TANIA. Environmental tobacco smoke during the early postnatal period of mice interferes with brain 18F-FDG uptake from infancy to early adulthood: a longitudinal study. Frontiers in Neuroscience, v. 14, p. 1-11, 2020. DOI: 10.3389/fnins.2020.00005

    Abstract: Exposure to environmental tobacco smoke (ETS) is associated with high morbidity and mortality, mainly in childhood. Our aim was to evaluate the effects of postnatal ETS exposure in the brain 2-deoxy-2-[18F]-fluoro-D-glucose (18F-FDG) uptake of mice by positron emission tomography (PET) neuroimaging in a longitudinal study. C57BL/6J mice were exposed to ETS that was generated from 3R4F cigarettes from postnatal day 3 (P3) to P14. PET analyses were performed in male and female mice during infancy (P15), adolescence (P35), and adulthood (P65). We observed that ETS exposure decreased 18F-FDG uptake in the whole brain, both left and right hemispheres, and frontal cortex in both male and female infant mice, while female infant mice exposed to ETS showed decreased 18F-FDG uptake in the cerebellum. In addition, all mice showed reduced 18F-FDG uptake in infancy, compared to adulthood in all analyzed VOIs. In adulthood, ETS exposure during the early postnatal period decreased brain 18FFDG uptake in adult male mice in the cortex, striatum, hippocampus, cingulate cortex, and thalamus when compared to control group. ETS induced an increase in 18F-FDG uptake in adult female mice when compared to control group in the brainstem and cingulate cortex. Moreover, male ETS-exposed animals showed decreased 18F-FDG uptake when compared to female ETS-exposed in the whole brain, brainstem, cortex, left amygdala, striatum, hippocampus, cingulate cortex, basal forebrain and septum, thalamus, hypothalamus, and midbrain. The present study shows that several brain regions are vulnerable to ETS exposure during the early postnatal period and these effects on 18F-FDG uptake are observed even a long time after the last exposure. This study corroborates our previous findings, strengthening the idea that exposure to tobacco smoke in a critical period interferes with brain development of mice from late infancy to early adulthood.

    Palavras-Chave: tobacco; tobacco smokes; nicotiana; environment; image processing; positron computed tomography; uptake; fluorodeoxyglucose; mice; glucose; longitudinal momentum; brain; children; nerve cells


  • IPEN-DOC 27138

    OLIVEIRA, J.R.B.; MORALLES, M. ; FLECHAS, D.; CARBONE, D.; CAVALLARO, M.; TORRESI, D.; ACOSTA, L.; AGODI, C.; AMADOR-VALENZUELA, P.; BONANNO, D.; BORELLO-LEWIN, T.; BRISCHETTO, G.A.; CALABRESE, S.; CALVO, D.; CAPIROSSI, V.; CAPPUZZELLO, F.; CHAVEZ-LOMELÍ, E.R.; CIRALDO, I.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; FOTI, A.; GALLO, G.; GUAZZELLI, M.A.; HACISALIHOGLU, A.; IAZZI, F.; LINARES, R.; LO PRESTI, D.; MA, J.; MEDINA, N.H.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; REITO, S.; RIES, P.; RUSSO, G.; SGOUROS, O.; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; SPATAFORA, A.; TUDISCO, S.; WANG, J.S.; YANG, Y.Y.; YILDIRIM, A.; ZAGATTO, V.A.B.. First comparison of GEANT4 hadrontherapy physics model with experimental data for a NUMEN project reaction case. European Physical Journal A, v. 56, n. 5, p. 1-9, 2020. DOI: 10.1140/epja/s10050-020-00152-6

    Abstract: Gamma-ray and neutron spectra from the 18O +76Se reaction at 15.3 MeV/u were measured with the EDEN array of liquid scintillators at the LNS. The results were compared to GEANT Hadrontherapy physics list simulations in order to assess the reliability of this model for the development of theNUMENproject.Agood agreement with the shape of the experimental gamma-ray spectra and a reasonable agreement with the total count rates were obtained. The gamma spectra originated from the nuclear reactions were selected by time coincidence with the Superconducting Cyclotron radio-frequency reference signal. The random coincidence background rate was appropriately described only when the Faraday Cup, the material and geometry of the experimental hall and its contents were included in the simulationwith sufficient detail. The information on the radiation spectra is important for the adequate development of the project of the detector arrays and electronic equipment for the advanced phase of NUMEN. Since orders of magnitude larger beam intensities are planned for this phase, the random coincidence rate is also of significant importance, particularly for the performance of the G-NUMEN gamma calorimeter array.

    Palavras-Chave: angular distribution; beam monitoring; coincidence spectrometry; computerized simulation; counting rates; energy spectra; external beam radiation therapy; faraday cups; g codes; gamma radiation; gamma spectra; gamma spectroscopy; mev range 100-1000; neutron spectra; neutrons; oxygen 18 beams; oxygen 18 reactions; selenium 76 target


  • IPEN-DOC 27135

    LOCOSSELLI, GIULIANO M.; MOREIRA, TIANA C.L.; CHACON-MADRID, KATHERINE; ARRUDA, MARCO A.Z.; CAMARGO, EVELYN P. de; KAMIGAUTI, LEONARDO Y.; TRINDADE, RICARDO I.F. da; ANDRADE, MARIA de F.; ANDRE, CARMEN D.S. de; ANDRE, PAULO A. de; SINGER, JULIO M.; SAIKI, MITIKO ; ZACCARELLI-MARINO, MARIA A.; SALDIVA, PAULO H.N.; BUCKERIDGE, MARCOS S.. Spatial-temporal variability of metal pollution across an industrial district, evidencing the environmental inequality in São Paulo. Environmental Pollution, v. 263, Part A, p. 1-8, 2020. DOI: 10.1016/j.envpol.2020.114583

    Abstract: Although air pollution decreased in some cities that shifted from an industrial to a service-based economy, and vehicular emission regulation became more restrictive, it is still a major risk factor for mortality worldwide. In central S~ao Paulo, Brazil, air quality monitoring stations and tree-ring analyses revealed a decreasing trend in the concentrations of particulate matter and metals. Such trends, however, may not be observed in industrial districts located in the urban periphery, where the usual mobile sources may be combined with local stationary sources. To evaluate environmental pollution in an industrial district in southeastern S~ao Paulo, we assessed its spatial variability, by measuring magnetic properties and concentrations of Al, Ba, Ca, Cl, Cu, Fe, K, Mg, Mn, P, S, Sr, Zn in the bark of 62 trees, and its temporal trends, by measuring Cd, Cu, Ni, Pb, V, Zn in tree rings of three trees. Source apportionment analysis based on tree barks revealed two clusters with high concentrations of metals, one related to vehicular and industrial emissions (Al, Ba, Cu, Fe, Zn) in the east side of the industrial cluster, and the other related to soil resuspension (Cu, Zn, Mn) in its west side. These patterns are also supported by the magnetic properties of bark associated with iron oxides and titanium-iron alloy concentrations. Dendrochemical analyses revealed that only the concentrations of Pb consistently decreased over the last four decades. The concentrations of Cd, Cu, Ni, V, and Zn did not significantly decrease over time, in contrast with their negative trends previously reported in central S~ao Paulo. This combined biomonitoring approach revealed spatial clusters of metal concentration in the vicinity of this industrial cluster and showed that the local population has not benefited from the decreasing polluting metal concentrations in the last decades.


  • IPEN-DOC 27134

    PELEGRINO, MILENA T.; KOHATSU, MARCIO Y.; SEABRA, AMEDEA B.; MONTEIRO, LUCILENA R. ; GOMES, DIEGO G.; OLIVEIRA, HALLEY C.; ROLIM, WALLACE R.; JESUS, TATIANE A. de; BATISTA, BRUNO L.; LANGE, CAMILA N.. Effects of copper oxide nanoparticles on growth of lettuce (Lactuca sativa L.) seedlings and possible implications of nitric oxide in their antioxidative defense. Environmental Monitoring and Assessment, v. 192, n. 4, p. 1-14, 2020. DOI: 10.1007/s10661-020-8188-3

    Abstract: Copper oxide nanoparticles (CuO NPs) have been extensively explored for use in agriculture. Previous studies have indicated that application of CuO NPs might be promising for development and conservation of plants, pest control, and for the recovery of degraded soils. However, depending on the applied concentration copper can cause phytotoxic effects. In this work, biosynthesized CuO NPs (using green tea extract) were evaluated on their effects on lettuce (Lactuca sativa L.) seedling growth, which were exposed at concentrations ranged between 0.2 and 300 μg mL−1. From the biosynthesized were obtained ultra-small CuO NPs (~ 6.6 nm), with high stability in aqueous suspension. Toxicity bioassays have shown that at low concentrations (up to 40 μg mL−1), CuO NPs did not affect or even enhanced the seed germination. At higher concentrations (higher than 40 μg mL−1), inhibition of seed germination and radicle growth ranging from 35 to 75% was observed. With the increase of CuO NPs concentrations, nitrite and S-nitrosothiols levels in radicles increased, whereas superoxide dismutase and total antioxidant activities decreased. The nitrite and Snitrosothiols levels in lettuce radicles showed a direct dose response to CuO NP application, which may indicate nitric oxide-dependent signaling pathways in the plant responses. Therefore, the results demonstrated that at low concentrations (≤ 20 μg mL−1) of CuO NPs, beneficial effects are obtained from seedlings, enhancing plant growth, and the involvement of nitric oxide signaling in the phytotoxic effects induced by high concentration of this formulation.


  • IPEN-DOC 27133

    COUTO, CAMILA P. ; REVILLA, REYNIER I.; COLOSIO, MARCO A.; COSTA, ISOLDA ; PANOSSIAN, ZEHBOUR; DE GRAEVE, IRIS; TERRYN, HERMAN; ROSSI, JESUALDO L. . Electrochemical behaviour of 22MnB5 steel coated with hot-dip Al-Si before and after hot-stamping process investigated by means of scanning Kelvin probe microscopy. Corrosion Science, v. 174, p. 1-10, 2020. DOI: 10.1016/j.corsci.2020.108811

    Abstract: Press-hardened steels are commonly protected with hot-dip Al-Si coating. Due to the electrochemical complexity of this system, either before or after hot-stamping process, SKPFM was used to investigate the influence of the thermo-mechanical process on the electrochemical behaviour of the galvanic coupling. The hot-stamping process changed significantly the anodic/cathodic coupling of the coating/steel due to iron enrichment in the coating layer. Hence, a concurrent mechanism was thoroughly established, i.e., while the press hardening enhances the corrosion properties of the steel system (steel and metallic coating) through diffusion, at the same time it diminishes the cathodic protection of the Al-Si layer.


  • IPEN-DOC 27132

    COELHO, EDNEI; REIS, TATIANA A.; COTRIM, MARYCEL ; MULLAN, THOMAS K.; CORREA, BENEDITO. Resistant fungi isolated from contaminated uranium mine in Brazil shows a high capacity to uptake uranium from water. Chemosphere, v. 248, p. 1-9, 2020. DOI: 10.1016/j.chemosphere.2020.126068

    Abstract: The Osamu Utsumi uranium mine occupies a 20 km2 area in the city of Caldas, which is located in the state of Minas Gerais, Brazil. Since mining activities ended at Osamu Utsumi 24 years ago, the surrounding area has become contaminated by acid effluents containing high concentrations of uranium. Thus, the aim of this study was to assess the uranium bioremediation capacity of 57 fungi isolated from the mine area. In tolerance tests, 38% (22) of the fungal isolates were considered tolerant to uranium, including 10 Penicillium species. At a uranium concentration of 2000 mg L 1 48 fungi did not exhibit mycelial growth index inhibition. Minimal inhibitory concentration (MIC) analysis showed growth of 25 fungi above a uranium concentration of 8000 mg L 1. At high uranium concentrations, some fungi (i.e., Talaromyces amestolkiae and Penicillium citrinum) showed morphological changes and pigment (melanin) production. Among the fungal isolates, those considered to be more tolerant to uranium were isolated from soil and sediment samples containing higher concentrations of heavy metal. When comparing the results of resistance/tolerance tests with those for uranium biosorption capacity, we concluded that the fungi isolated from the Osamu Utsumi mine with the best potential for uranium bioremediation were Gongronella butleri, Penicillium piscarium, Penicillium citrinum, Penicillium ludwigii, and Talaromyces amestolkiae. Biosorption tests with live fungal biomass showed that 11 species had a high potential for uranium uptake from contaminated water.


  • IPEN-DOC 27131

    DUARTE, LUIS F. de A.; BLASCO, JULIAN; CATHARINO, MARILIA G.M. ; MOREIRA, EDSON G. ; TROMBINI, CHIARA; NOBRE, CAIO R.; MORENO, BEATRIZ B.; ABESSA, DENIS M. de S.; PEREIRA, CAMILO D.S.. Lead toxicity on a sentinel species subpopulation inhabiting mangroves with different status conservation. Chemosphere, v. 251, p. 1-13, 2020. DOI: 10.1016/j.chemosphere.2020.126394

    Abstract: Lead is a priority pollutant introduced in the aquatic environment by different sources commonly located in estuarine regions, such as ports, marinas and industries. Environmental agencies around the world set the maximum allowable concentration of lead in effluents, surface water and sediment, but few studies reported its accumulation and chronic toxicity in mangrove benthic invertebrates using concentrations believed to be safe. In the case of Brazilian mangrove environments, Ucides cordatus is a crab species of choice to be used in bioaccumulation studies. We have assessed biomarkers’ responses (DNA strand breaks, micronucleated cells, metallothioneins, enzymatic activity of aminolevulinic acid dehydratase and neutral red retention time) and the total bioaccumulation in six tissues of U. cordatus crabs resident to mangrove areas under different conservation status during a 28-day period bioassay. We also investigated Pb subcellular partition and biomarkers’ responses using a supposedly safe concentration (10 mg L 1). During the Pb exposure, the highest concentration of Pb was observed in crab gills. Crabs also showed a high ability to allocate Pb in detoxified forms. Multivariate analysis pointed out that bioaccumulation (total, active and detoxified) is linked to biomarkers. Even in supposedly safe dosage, U. cordatus triggered its defense mechanisms expressing more metallothioneins and presented relevant cyto-genotoxic damage. Our data suggest the development of biological tolerance to Pb in crabs from polluted areas. Our results provided a new insight about lead toxicity even at concentrations considered environmentally safe, which could support new strategies to manage estuarine areas considering their respective conservation status.


  • IPEN-DOC 27130

    RICHARD, DIEGO; RENTERÍA, MARIO; CARBONARI, ARTUR W. ; ROMERO, MARIANO; FACCIO, RICARDO. Preparation of In-doped Y2O3 ceramics through a sol-gel process: effects on the structural and electronic properties. Ceramics International, v. 46, n. 10, p. 16088-16095, 2020. DOI: 10.1016/j.ceramint.2020.03.161

    Abstract: The Pechini-type sol-gel (PSG) process has been used for the preparation of doped oxides due to its capability to overcome most of the difficulties that frequently occur by using other producing methods. In this work we analyze the case of samples of pure and In-doped yttria (Y2O3) prepared by the PSG process. We experimentally characterize the synthesized samples by x-ray diffraction, micro-Raman spectroscopy, electrochemical impedance spectroscopy (EIS), and time-differential perturbed γ-γ angular correlation (PAC) spectroscopy, and we compare these results with those obtained starting from commercial oxide powders. We found that the PSG process can be used to successfully produce doped yttria in the cubic phase, with the impurities substitutionally located at the cationic sites of the structure. By the proposed PSG route, the inclusion of impurities does not affect the particle size nor the resistivity. However, when we compare the PSG samples with other samples produced from commercial powder, we found that the first have lower resistivities at grain interiors. On the other hand, PAC spectroscopy in 111In(→111Cd)-doped yttria allows the study of the dynamic hyperfine interactions observed by the radioactive 111Cd impurity-probe, which can be used to “sense” the host electron availability near the impurities after the electron-capture decay of 111In. Differences between PAC spectra for PSG samples and the commercial powder suggest that the PSG process introduces additional donor defects into the yttria electronic structure, which is consistent with the lower resistivity observed in the PSG samples by EIS spectroscopy.


  • IPEN-DOC 27129

    BERTOLETE, M.; BARBOSA, P.A. ; ROSSI, WAGNER de ; FREDERICCI, C.; MACHADO, I.F.. Mechanical characterisation and machining evaluation of ceramic cutting tools functionally graded with six layers. Ceramics International, v. 46, n. 10, p. 15137-15145, 2020. DOI: 10.1016/j.ceramint.2020.03.048

    Abstract: Functionally graded materials (FGMs) are composites graded in one or more directions by the mean volume fraction variation of their constituents in a continuous or stepwise design. The objective of this study is to apply the FGM concept to ceramic cutting tools to widen its application range. Thus, two cutting tool materials were selected: cemented carbide, owing to its higher toughness, and alumina-based ceramic, owing to its high wear resistance at elevated temperatures. Ceramics based on alumina were functionally graded with cemented carbide and sintered using the spark plasma sintering technique. The thermal residual stresses were predicted; additionally, the microstructure, relative density, and Vickers hardness and fracture toughness for the alumina layer were evaluated, and flexural strength and machining tests were conducted. From the results, cracks were not observed in the microstructure and full density was obtained. In general, the hardness and fracture toughness values were close to those in the literature. A flexural strength improvement of at least 50% on FGM samples was observed in comparison to homogeneous ceramic ones. The FGM cutting tools supported approximately 1000 N of machining force without catastrophic failure when turning martensitic stainless steel into a conventional lathe. The values of surface roughness (Ra and Rz) agree with those in the literature under similar cutting and geometry conditions.


  • IPEN-DOC 27128

    VIEIRA, LAÍS H.S.; SABINO, CARLA M.S.; SOARES JÚNIOR, FRANCISCO H.; ROCHA, JANAINA S.; CASTRO, MANUELA O.; ALENCAR, RAFAEL S.; COSTA, LUELC S. da; VIANA, BARTOLOMEU C.; PAULA, AMAURI J. de; SOARES, JOAO M.; SOUZA FILHO, ANTONIO G.; OTUBO, LARISSA ; FECHINE, PIERRE B.A.; GHOSH, ANUPAMA; FERREIRA, ODAIR P.. Strategic design of magnetic carbonaceous nanocomposites and its application as multifunctional adsorbent. Carbon, v. 161, p. 758-771, 2020. DOI: 10.1016/j.carbon.2020.01.089

    Abstract: Magnetic carbonaceous nanocomposites (MCN) were prepared by hydrothermal carbonization (HTC) of a carbohydrate in the presence of Fe3þ, followed by thermal treatment with KOH for simultaneous activation and magnetization. The precursor formed (IOCN) in the HTC process contained iron oxide nanoparticles encapsulated in the hydrochar matrix. The thermochemical parameters of the activation (temperature and IOCN/KOH mass-ratio) were varied to achieve an increase of the specific surface area along with formation of magnetic phases in MCN compared to IOCN. Activation temperature was found to be responsible for the structural and morphological properties of the MCNs whereas the IOCN/KOH mass-ratio controlled the porosity. The magnetic properties of the MCNs originated from the formation of Fe3O4 and Fe0 phases, which are encapsulated in the carbonaceous material. The MCNs were tested for adsorption of methylene blue (MB) dye, followed by magnetic separation. The MCN, produced in the optimized conditions, showed a specific surface area of 766 m2 g 1, magnetization of 8 emu g 1 and a MB adsorption capacity of 570 mg g 1. Detailed kinetic and isotherm studies of MB adsorption were also performed. The methodology of simultaneous activation and magnetization to generate MCNs, presented here, could be extended to obtain new multifunctional carbon-based nanocomposite adsorbent starting from different biomasses.


  • IPEN-DOC 27127

    BORDON, ISABELLA C.; JOVIANO, WILLIAN R.; MEDEIROS, ALINE M.Z. de; CAMPOS, BRUNO G. de; ARAUJO, GIULIANA S. de; GUSSO-CHOUERI, PALOMA K.; PRETO, MAYRA de F.; FAVARO, DEBORAH I.T. ; ABESSA, DENIS M. de S.. Heavy metals in tissues of blue crabs Callinectes danae from a subtropical protected estuary influenced by mining residues. Bulletin of Environmental Contamination and Toxicology, v. 104, n. 4, p. 418-422, 2020. DOI: 10.1007/s00128-020-02815-y

    Abstract: This short note aims to report in detail a preliminary assessment of the concentrations of Cd, Hg and Pb in tissues of blue crabs Callinectes danae collected from the Cananéia-Iguape-Peruíbe estuarine complex (CIP), in the South of São Paulo State coast, Brazil. In October 2014, blue crabs were collected from CIP. Tissues were removed by dissection and metal determination was performed by GF-AAS and CV-AAS. According to statistical analysis, Pb and Cd concentrations in gills were significantly higher than those found in muscles and hepatopancreas, respectively. There were no significant differences in Hg concentrations between samples. Cd, Hg and Pb concentrations in gills and hepatopancreas were lower than those reported in a previous study performed at CIP. However, Cd concentration in hepatopancreas was higher than the Brazilian limit for consumption and new efforts to monitor Cd concentrations in C. danae tissues must be performed.


  • IPEN-DOC 27126

    DALTOE, FELIPE P.; OLIVEIRA, NÉLIO A.J. de ; PERONI, CIBELE N. ; SHARPE, PAUL T.; MANTESSO, ANDREA. Phenotype changes of oral epithelial stem cells after in vitro culture. Brazilian Oral Research, v. 34, p. 1-8, 2020. DOI: 10.1590/1807-3107bor-2020.vol34.0033

    Abstract: The aim of our study was to isolate populations of keratinocyte stem cells based on the expression of cell surface markers and to investigate whether the culture could affect their phenotype. keratinocytes from human oral mucosa were sorted based on the expression of the epithelial stem cell markers p75NTR and CD71. We also examined the co-expression of other epithelial stem markers such as integrins β1 and α6 and their stem cell-like proprieties in in vitro assays. Three passages after being sorted by MACS, more than 93% of the p75NTR+ve cells lost the expression of p75NTR, while 5.46% of the p75NTR-ve gained it. Within the small population of the p75NTR+ve cells, 88% co-expressed other epithelial stem cell markers such as integrins β1 and α6, while only 28% of p75NTR-ve cells co-expressed these markers. These results were confirmed by sorting cells by FACS. Additionally, when double staining was used for sorting cells, 99% of the p75NTR+veCD71-ve and 33% of the p75NTR-veCD71+ve cells expressed both integrins, but just one week after culture, only 1.74% of the p75NTR+veCD71-ve cells still expressed p75NTR and only 0.32% still expressed CD71. Similar results were obtained when co-culturing p75NTR+ve and p75NTR-ve populations before analysis. Our results suggest that phenotype changes may be part of an intrinsic cellular mechanism to conserve levels of protein expression as they may found in the human body. In addition, in vitro culture may not offer ideal conditions for epithelial stem cell maintenance due to phenotype changes under standard culture conditions.


  • IPEN-DOC 27125

    BELLEZZO, MURILLO ; FONSECA, GABRIEL P.; VONCKEN, ROBERT; VERRIJSSEN, AN-SOFIE; VAN BEVEREN, CELINE; ROELOFS, ERIK; YORIYAZ, HELIO ; RENIERS, BRIGITTE; VAN LIMBERGEN, EVERT J.; BERB EE, MAAIKE; VERHAEGEN, FRANK. Advanced design, simulation, and dosimetry of a novel rectal applicator for contact brachytherapy with a conventional HDR 192Ir source. Brachytherapy, v. 19, n. 4, p. 544-553, 2020. DOI: 10.1016/j.brachy.2020.03.009

    Abstract: PURPOSE: Dose escalation yields higher complete response to rectal tumors, which may enable the omission of surgery. Dose escalation using 50 kVp contact x-ray brachytherapy (CXB) allow the treatment of a selective volume, resulting in low toxicity and organs-at-risk preservation. However, the use of CXB devices is limited because of its high cost and lack of treatment planning tools. Hence, the MAASTRO applicator (for HDR 192Ir sources) was developed and characterized by measurements and Monte Carlo simulations to be a cost-effective alternative to CXB devices. METHODS AND MATERIALS: A cylindrical applicator with lateral shielding was designed to be used with a rectoscope using its tip as treatment surface. Both the applicator and the rectoscope have a slanted edge to potentially allow easier placement against tumors. The applicator design was achieved by Monte Carlo modeling and validated experimentally with film dosimetry, using the Papillon 50 (P50) device as reference. RESULTS: The applicator delivers CXB doses in less than 9 min using a 20375 U source for a treatment area of approximately 20 20 mm2 at 2 mm depth. Normalized at 2 mm, the dose falloff for depths of 0 mm, 5 mm, and 10 mm are 130%, 70%, and 43% for the P50 and 140%, 67%, and 38% for the MAASTRO applicator, respectively. CONCLUSIONS: The MAASTRO applicator was designed to use HDR 192Ir sources to deliver a dose distribution similar to those of CXB devices. The applicator may provide a cost-effective solution for endoluminal boosting with clinical treatment planning system integration.


  • IPEN-DOC 27124

    COURROL, LILIA C.; ESPINOZA-CULUPÚ, ABRAHAM; SILVA JUNIOR, PEDRO I. da; GONÇALVES, KARINA de O.; SILVA, FLAVIA R. de O. ; BORGES, MONAMARIS M.. Antibacterial and antitumoral activities of the spider acylpolyamine Mygalin silver nanoparticles. BioNanoScience, v. 10, n. 2, p. 463-472, 2020. DOI: 10.1007/s12668-020-00738-w

    Abstract: Mygalin is a synthetic analog of polyamine spermidine isolated from spider hemocytes. Polyamines show potential therapeutic activity against a wide range of human diseases such as cancer and microbial infections. In this work, we analyzed the antibacterial and antitumoral activities of Mygalin silver nanoparticles synthesized by the photoreduction method. The formation and distribution of MygAgNPs were confirmed by UV-visible spectroscopy, zeta potential, and transmission electron microscopy. The obtained nanoparticles were mostly spherical with a particle size distribution in the range of ~ 10–60 nm. We have demonstrated that MygAgNPs increased the effectiveness of the native Mygalin by approximately 6400-fold. Cytotoxicity tests were performed, and it was possible to reach a concentration that was not toxic to healthy cells (NHI-3T3) and at the same time toxic to the tumor cell line (MCF-7). The obtained results suggest that this system shows potential enhanced antibacterial activity against Escherichia coli, DH5α and anticancer activity against MCF-7 cell line.


  • IPEN-DOC 27123

    MOREIRA, GREGORI de A. ; GUERRERO-RASCADO, JUAN L.; BRAVO-ARANDA, JUAN A.; FOYO-MORENO, INMACULADA; CAZORLA, ALBERTO; ALADOS, INMACULADA; LYAMANI, HASSAN; LANDULFO, EDUARDO ; ALADOS-ARBOLEDAS, LUCAS. Study of the planetary boundary layer height in an urban environment using a combination of microwave radiometer and ceilometer. Atmospheric Research, v. 240, p. 1-15, 2020. DOI: 10.1016/j.atmosres.2020.104932

    Abstract: The Planetary Boundary Layer (PBL) is an important part of the atmosphere that is relevant in different atmospheric fields like pollutant dispersion, and weather forecasting. In this study, we analyze four and five-year datasets of measurements gathered with a ceilometer and a microwave radiometer to study the PBL structure respectively, in the mid-latitude urban area of Granada (Spain). The methodologies applied for the PBL Height (PBLH) detection (gradient method for ceilometer and the combination of parcel method and temperature gradient method for microwave radiometer) provided a description in agreement with the literature about the PBL structure under simple scenarios. Then, the PBLH behavior is characterized by a statistical study of the convective and stable situations, so that the PBLH was obtained from microwave radiometer measurements. The analysis of the PBLH statistical study shows some agreement with other PBLH studies such as daily pattern and yearly cycle, and the discrepancies were explained in terms of distinct latitudes, topography and climate conditions. Finally, it was performed a joint long-term analysis of the residual layer (RL) provided by ceilometer and the stable and convective layer heights determined by microwave radiometer, offering a complete picture of the PBL evolution by synergetic combination of remote sensing techniques. The PBL behavior has been used for explaining the daily cycle of Black Carbon (BC) concentration, used as tracer of the pollutants emissions associated to traffic.


  • IPEN-DOC 27122

    DAFRÉ-MARTINELLI, MARCELLE; FIGUEIREDO, ANA M.G. ; DOMINGOS, MARISA. Trace element leaf accumulation in native trees from the remaining Semideciduous Atlantic Forest in Brazil. Atmospheric Pollution Research, v. 11, n. 5, p. 871-879, 2020. DOI: 10.1016/j.apr.2020.01.015

    Abstract: Remnants of Semideciduous Atlantic Forest surrounded by numerous industries, intense road traffic and agricultural lands in Southeast Brazil have been affected by trace elements. We implemented a passive biomonitoring with the three most abundant native tree species (Astronium graveolens, Croton floribundus and Piptadenia gonoacantha) to answer these questions: 1) which species has the greatest potential to accumulate trace elements?; 2) does the leaf accumulation level of trace elements vary between the edge and interior of the forest remnants, between dry and wet periods or due to the distance from the industrial area?; 3) which species, among the most abundant in the forest remnants, would better indicate the spatial variations in trace elements pollution and which elements would be the most relevant for such spatial discrimination? Leaf samples were collected during the dry and wet seasons, at the edge and interior of four forest remnants. Trace elements were determined using inductively coupled plasma mass spectrometry (ICP MS). Few edge effects were evidenced in the leaf concentrations in all species. Higher concentrations of most trace elements were measured during dry season. Although C. floribundus showed the most accumulating capacity, A. graveolens was the most appropriate species to discriminate spatial variations. The forest closer to the industrial area was distinguished from the others by Mn and Ni from oil burning, but the metal pollution from the industrial area did not interfere on the leaf concentrations in A. graveolens sampled in the urban and rural forests.


  • IPEN-DOC 27121

    ARAUJO, G.S.; GUSSO-CHOUERI, P.K.; FAVARO, D.I.T. ; ROCHA, R.C.C.; SAINT'PIERRE, T.D.; HAUSER-DAVIS, R.A.; BRAZ, B.; SANTELLI, R.E.; FREIRE, A.S.; MACHADO, W.T.V.; CRUZ, A.C.F.; ABESSA, D.M.S.. Metal‑associated biomarker responses in crabs from a marine protected area in Southeastern Brazil. Archives of Environmental Contamination and Toxicology, v. 78, n. 3, p. 463-477, 2020. DOI: 10.1007/s00244-020-00710-5

    Abstract: The environmental quality of a Ramsar wetland site located at the Cananéia-Iguape-Peruíbe Protected Area (CIP-PA), in São Paulo, Brazil, was assessed by geochemical analyses and biomarker assessments (GPx, GST, GSH, GST, MT, LPO, DNA damage) performed in swimming crab Callinectes danae Smith, 1869 organs (posterior and anterior gills and hepatopancreas) to estimate sediment contaminant bioavailability. The results indicated that two sampling stations, PT and PM, exhibited the worst environmental conditions, as sediments collected at both points contained metal contamination, while crabs exhibited significant responses for GPx, GST, and LPO (mostly during winter). Sediment contamination tended to be associated to fine sediments (both seasons) and organic matter (winter). During the summer survey, Pb concentrations in sediments of station PT exceeded the Brazilian Sediment Quality Guidelines (SQGs) and the Canadian Interim Marine Sediment Quality Guidelines. Metal concentrations in sediments sampled in winter were higher compared with summer, with Co, Ni, and Pb exceeding SQGs levels at PT, whereas Co, Ni, Hg, Zn, and Pb exceeded SQGs at PM. Biomarker induction during summer appeared to be caused by natural variables (water salinity and temperature, and molting cycle), whereas oxidative stress and tissue damage during winter appeared to be more clearly linked to metal contamination. Anterior gills presented the clearest signs of seasonal variability, being more responsive to sediment contamination. The results suggest that metals originated from the upper Ribeira de Iguape River are transported toward the estuarine system, causing effects on C. danae individuals. Additionally, seasonality is a strong factor concerning CIP-PA toxicity, since the rainfall regime significantly modifies the freshwater flow and, consequently, estuarine water salinity, suspended particle and metal inputs, as well as the location of depositional areas. Thus, efforts to mitigate CIP-PA contamination should be based on the control of upstream pollution sources.


  • IPEN-DOC 27120

    CASTRO, PEDRO A.A. ; LIMA, CASSIO A. ; MORAIS, MYCHEL R.P.T.; ZORN, TELMA M.T.; ZEZELL, DENISE M. . Monitoring the progress and healing status of burn wounds using infrared spectroscopy. Applied Spectroscopy, v. 74, n. 7, p. 758-766, 2020. DOI: 10.1177/0003702820919446

    Abstract: Burns are one of the leading causes of morbidity worldwide and the most costly traumatic injuries. A better understanding of the molecular mechanisms in wound healing is required to accelerate tissue recovery and reduce the health economic impact. However, the standard techniques used to evaluate the biological events associated to wound repair are laborious, time-consuming, and/or require multiple assays/staining. Therefore, this study aims to evaluate the feasibility of Fourier transform infrared (FT-IR) spectroscopy to monitor the progress and healing status of burn wounds. Burn injuries were induced on Wistar rats by water vapor exposure and biopsied for further histopathological and spectroscopic evaluation at four time-points (3, 7, 14, and 21 days). Spectral data were preprocessed and compared by principal component analysis. Pairwise comparison of post-burn groups to each other revealed that metabolic activity induced by thermal injury decreases as the healing progresses. Higher amounts of carbohydrates, proteins, lipids, and nucleic acids were evidenced on days 3 and 7 compared to healthy skin and reduced amounts of these molecular structural units on days 14 and 21 postburn. FT-IR spectroscopy was used to determine the healing status of a wound based on the biochemical information retained by spectral signatures in each phase of healing. Our findings demonstrate that FT-IR spectroscopy can monitor the biological events triggered by burn trauma as well as to detect the wound status including full recovery based on the spectral changes associated to the biochemical events in each phase.


  • IPEN-DOC 27119

    SILVA JÚNIOR, IREMAR A. da ; SIQUEIRA, PAULO de T.D. ; NASCIMENTO, EDUARDO do; YORIYAZ, HELIO ; SORDI, GIAN-MARIA A.A. ; POTIENS, MARIA da P.A. . Variability: surface intensity distribution of large-area reference sources. Applied Radiation and Isotopes, v. 160, p. 1-7, 2020. DOI: 10.1016/j.apradiso.2020.109108

    Abstract: In this paper we present the impact of variability, a surface source parameter, on the efficiency evaluation of surface contamination monitors. This study was based on two source uniformity correction methodologies and data from real surface source distributions. Surface source intensity distribution has been changed by rearranging the cells (portions of the active area of each LARS) while keeping the same source uniformity value. Instrument efficiencies have been calculated for different sets of uniformities and variabilities. This study led to emphasize the importance of variability, a differential source intensity distribution parameter, over the uniformity, an integral source intensity distribution parameter, and reinforced the importance of the source uniformity correction procedure on the course of surface contamination monitor calibration.


  • IPEN-DOC 27118

    YAMAZAKI, I.M. ; KOSKINAS, M.F. ; MOREIRA, D.S. ; SEMMLER, R. ; BRANCACCIO, F. ; DIAS, M.S. . Primary standardization and determination of gamma ray emission intensities of Ho-166. Applied Radiation and Isotopes, v. 164, p. 1-6, 2020. DOI: 10.1016/j.apradiso.2020.109237

    Abstract: The procedure followed by the Nuclear Metrology Laboratory (LMN) at the IPEN-CNEN/SP, in S~ao Paulo, for the primary standardization of 166Ho is described. The activity of 166Ho was determined by the efficiency extrapolation technique applied to a 4πβ(PC)-γ coincidence system using a gas flow proportional counter in 4π geometry coupled to a 76 x 76 mm NaI(Tl) crystal. The results for the γ-rays intensities at 80.57 and 1379.45 keV were 0.0651(11) and 0.00904(11), respectively.


  • IPEN-DOC 27117

    SILVA JÚNIOR, IREMAR A. ; SIQUEIRA, PAULO de T.D. ; NASCIMENTO, EDUARDO do; YORIYAZ, HELIO ; SORDI, GIAN-MARIA A.A. ; VIVOLO, VITOR ; POTIENS, MARIA da P.A. . Correction factors for non-uniform large-area reference sources. Applied Radiation and Isotopes, v. 160, p. 1-6, 2020. DOI: 10.1016/j.apradiso.2020.109082

    Abstract: Based on uniformity measurements of large-area reference sources used in calibration procedures of surface contamination monitors, an investigation was carried out to obtain a method that estimates the bias originated from surface source intensity distribution deviation from the ideal uniform distribution and corrects it. It relies on correcting the estimated instrument efficiency by applying correction factors driven from the uniformity distribution profiles of the sources used in calibration procedure. Simulations of the monitor calibration procedure are run for 2 distinct surface source distributions: the real and the ideally uniform distributions. Correction factors are driven from counting rate estimates obtained from each source representation. In order to evaluate adequacy of this proposition it was validated against a method proposed by the NPL in the Good Practices Guide No.14.


  • IPEN-DOC 27116

    LECONTE, P.; ARCHIER, P.; DE SAINT JEAN, C.; DINIZ, R. ; SANTOS, ADIMIR dos ; FAUTRAT, L.; FOLIGNO, D.; GESLOT, B.; GILAD, E.; TAMAGNO, P.; TRUCHET, G.; ZOIA, A.. New delayed neutron group constants and covariances for LWR core applications, combining summation calculations and integral experiments. Annals of Nuclear Energy, v. 139, p. 1-9, 2020. DOI: 10.1016/j.anucene.2019.107250


  • IPEN-DOC 27115


    Abstract: The possibility to use a special class of heavy-ion induced direct reactions, such as double charge exchange reactions, is discussed in view of their application to extract information that may be helpful to determinate the nuclear matrix elements entering in the expression of neutrinoless double beta decay half-life. The methodology of the experimental campaign presently running at INFN - Laboratori Nazionali del Sud is reported and the experimental challenges characterizing such activity are described.


  • IPEN-DOC 27114

    COUTO, CAMILA P. ; COSTA, ISOLDA ; VIVEIROS, BARBARA V.G. de ; ALENCAR, MAICON C. de ; COLOSIO, MARCO A.; PANOSSIAN, ZEHBOUR; ROSSI, JESUALDO L. . The use of scanning vibrating electrode technique to evaluate the effect of hot stamping on the corrosion resistance of 22MnB5 press-hardened steel electroplated with Zn-Ni. Materials Research, v. 22, suppl. 1, p. 1-6, 2019. DOI: 10.1590/1980-5373-MR-2019-0163

    Abstract: Carmakers must achieve the worldwide targets for lightweight materials, safety and reducing the fuel consumption. The use of press-hardened steel (PHS), in vehicle structures has been contributing with these requirements. This type of steel is widely used for the hot-stamping which consists in heating the steel blank to total austenitization temperature and then transferring it from the furnace into the die tool where the steel is formed and quenched at the same time. PHS is usually protect with metallic coatings in order to avoid both steel oxidation and decarburization. Hot-dip Al-Si coating is currently the main used in this application. However, alternative coatings, like zinc-based, are under investigation. This work aims at evaluating the corrosion resistance of the 22MnB5 grade PHS, electroplated with Zn-Ni, before and after hot stamping, using the scanning vibrating electrode technique (SVET). Results from SVET showed that samples prior to hot stamping, the corrosion mechanism was uniform over the exposed surface, and was mainly related to selective dissolution of zinc from the coating. On the other hand, hot stamped samples showed localized corrosion mechanism with decrease in current with time of immersion due to the formation of corrosion products on the exposed surface.


  • IPEN-DOC 27113

    MUNAWAR, AISHA; AKREM, AHMED; HUSSAIN, ASHIQ; SPENCER, PATRICK ; BETZEL, CHRISTIAN. Molecular model of cytotoxin-1 from Naja mossambica mossambica venom in complex with chymotrypsin. Theoretical Biology Forum, v. 108, n. 1-2, p. 89-99, 2015. DOI: 10.1400/240197

    Abstract: Snake venom is a myriad of biologically active proteins and peptides. Three finger toxins are highly conserved in their molecular structure, but interestingly possess diverse biological functions. During the course of evolution the introduction of subtle mutations in loop regions and slight variations in the three dimensional structure, has resulted in their functional versatility. Cytotoxin-1 (UniProt ID: P01467), isolated from Naja mossambica mossambica, showed the potential to inhibit chymotrypsin and the chymotryptic activity of the 20S proteasome. In the present work we describe a molecular model of cytotoxin- 1 in complex with chymotrypsin, prepared by the online server ClusPro. Analysis of the molecular model shows that Cytotoxin-1 (P01467) binds to chymotrypsin through its loop I located near the N-terminus. The concave side of loop I of the toxin fits well in the substrate binding pocket of the protease. We propose Phe10 as the dedicated P1 site of the ligand. Being a potent inhibitor of the 20S proteasome, cytotoxin-1 (P01467) can serve as a potential antitumor agent. Already snake venom cytotoxins have been investigated for their ability as an anticancer agent. The molecular model of cytotoxin-1 in complex with chymotrypsin provides important information towards understanding the complex formation.


  • IPEN-DOC 27111

    REIS, S.L. ; MUCCILLO, E.N.S. . Ionic conductivity of doped lanthanum gallate and strontium gallate composites. ECS Transactions, v. 80, n. 9, p. 141-149, 2017. DOI: 10.1149/08009.0141ecst

    Abstract: Polycrystalline ceramic solid electrolytes based on strontium- and magnesium-doped lanthanum gallate exhibit high ionic conductivity and find potential application in solid oxide fuel cells operating at intermediate temperatures. Sintering of this solid electrolyte is usually carried out at high temperatures, being responsible for loss of Ga and consequent formation of impurity phases. In this work, composites consisting of La0.9Sr0.1Ga0.8Mg0.2O3-δ with additions of strontium gallate were prepared by solid state reaction, and the influence of the additiveon electrical conductivity and phase composition of the composite electrolyte was investigated. The sintered density of composites is higher than 95% of the theoretical value after sintering at 1350°C. The contents of impurity phases decreased with increasing additions of strontium gallate. The overall ionic conductivity of the composites is higher than that of LSGM. This effect is attributed to the decrease in the fraction of free MgO at grain boundaries in the composites.


  • IPEN-DOC 27106

    RODRIGUES, ANTONIO C.I. ; MADI FILHO, TUFIC ; SILVA, DAVILSON G. da . Analysis and construction of the high density storage racks for spent fuel of the research reactor IEA-R1. RAD Conference Proceedings, v. 3, p. 123-126, 2018. DOI: 10.21175/RadProc.2018.27

    Abstract: The IEA-R1 research reactor works 40h weekly, with 4.5 Mw power. The storage rack for spent fuel elements has less than half of its initial capacity. Under these conditions, the reactor operating for 32h/week will have 3 spent fuel by year, approximately 3 utilization rate Positions/year; thus, we will have only about six years of capacity for storage. Since the desired service life of the IEA-R1 is at least another 20 years, it will be necessary to increase the storage capacity of spent fuel by doubling the wet storage in the reactor’s pool. 3M’s neutron absorber BoralcanTM was chosen after reviewing the literature about available materials for the construction of a new storage rack. This work presents studies for the construction of new storage racks with double of capacity using the same place of the current ones. Criticality safety analysis was performed with MCNP-5 Monte Carlo code, using two Evaluated Nuclear Data Files (ENDF/B-VI and ENDF/B-VII) in calculations, and subsequently, the results were compared. The full charge of the storage rack with only new fuel elements (maximum reactivity) was considered to calculate the keff. The results obtained in the simulations show that it is possible doubling the storage capacity of the spent fuel elements. Additionally, it complies with safety limits established by International Atomic Energy Agency (IAEA) and Brazilian Commission of Nuclear Energy (CNEN) standards to the criticality criteria (keff <0.95). This is only possible with the use of neutron absorber material.


  • IPEN-DOC 27105

    OTON, LAIS F.; OLIVEIRA, ALCINEIA C.; ARAUJO, JESUINA C.S. de; ARAUJO, RINALDO S.; SOUSA, FRANCISCO F. de; SARAIVA, GILBERTO D.; LANG, ROSSANO; OTUBO, LARISSA; DUARTE, GIAN C. da S.; CAMPOS, ADRIANA. Selective catalytic reduction of NOx by CO (CO-SCR) over metal-supported nanoparticles dispersed on porous alumina. Advanced Powder Technology, v. 31, n. 1, p. 464-476, 2020. DOI: 10.1016/j.apt.2019.11.003

    Abstract: The selective catalytic reduction of NOx by CO (CO-SCR) was investigated over metals supported on porous alumina. The Pt, Co, Fe and Ni nanoparticles were dispersed on the alumina and characterized by XRD, textural properties, FTIR spectroscopy, chemical analyses, Py adsorption followed by FTIR measurements, HRTEM and SEM-EDS. Among the solids studied, the Pt/Al2O3 and NiPt/Al2O3 catalysts exhibited improved performance due to the interaction and synergy between the Pt(Ni) nanoparticles and the support. In other words, the electron transfer facility between the PtOx(Ni) and chlorined Pt species on the support provided a more active solid in the CO-SCR reaction. The surface acidity of Lewis acid sites and the porous features of the Pt/Al2O3 and NiPt/Al2O3 catalysts also contributed significantly to the high performance of these materials in the NOx conversion. The Pt/Al2O3 and NiPt/Al2O3 catalysts were tolerant to the poisoning by SO2 and H2O and depicted a superior catalytic performance, compared to the other solids.


  • IPEN-DOC 26678

    CABRAL, FERNANDA V. ; SABINO, CAETANO P.; DIMMER, JESICA A.; SAUTER, ISMAEL P. ; CORTEZ, MAURO J.; RIBEIRO, MARTHA S. . Preclinical investigation of methylene blue-mediated antimicrobial photodynamic therapy on Leishmania parasites using real-time bioluminescence. Photochemistry and Photobiology, v. 96, n. 3, p. 604-610, 2020. DOI: 10.1111/php.13188

    Abstract: Cutaneous leishmaniasis (CL) is a neglected disease that promotes destructive lesions. Difficulties in treatment are related to accessibility of drugs, resistance and toxicity. Antimicrobial photodynamic therapy (APDT) has been emerging as a promising treatment for CL. In this work, we evaluated methylene blue (MB)-mediated APDT (MB-APDT) on Leishmania amazonensis in vitro and in vivo by bioluminescence technique. In vitro, MB-APDT was performed using a red LED (k = 660 11 nm, 100 mW cm 2) and MB (100 μM) at different light doses. In vivo, mice were infected and 4 weeks later, randomly divided into three groups: control, APDT 1 (single session) and APDT 2 (two sessions of MB-APDT). MB was used at 100 μM and energy dose was established at 150 J cm 2. Parasite burden, lesion size and pain were evaluated weekly for 4 weeks. In vitro, lethal dose for 90% parasite inactivation was achieved at 48.8 J cm 2. In vivo, although APDT 1 and APDT 2 groups have showed similar parasite burden after 4 weeks, two sessions were clinically better, especially considering the inflammatory process associated to CL. Our findings reinforce MB-APDT as a costeffective treatment to combat CL.


  • IPEN-DOC 26454

    LOBO, ALEXANDRE R.; GAIEVSKI, EDUARDO H.S.; MESQUITA, CARLOS H. de ; DE CARLI, EDUARDO; TEIXEIRA, PRYSCILA D.S.; PEREIRA, ROSA M.R.; BORELLI, PRIMAVERA; SÁ, LILIAN R.M. de; COLLI, CELIA. Increased adiposity by feeding growing rats a high-fat diet results in iron decompartmentalisation. British Journal of Nutrition, v. 123, n. 10, p. 1094-1108, 2020. DOI: 10.1017/S0007114519002320

    Abstract: The present study reports the effects of a high-fat (HF) diet of over 8 weeks on the Fe status of growing rats. Tissue Fe levels were analysed by atomic absorption spectrophotometry, and whole-body adiposity was measured by dual-energy X-ray absorptiometry. Histopathology and morphometry of adipose tissue were performed. Liver homogenates were used for measuring ferroportin-1 protein levels by immunoblotting, and transcript levels were used for Fe genes measured by real-time PCR. Tissue Fe pools were fit to a compartmental biokinetic model in which Fe was assessed using fourteen compartments and twenty-seven transfer constants (kj,i from tissue ‘i’ to tissue ‘j’) adapted from the International Commission on Radiological Protection (ICRP) 69. Ten kj,i were calculated from the experimental data using non-linear regression, and seventeen were estimated by allometry according to the formula ki;j ¼ a ×Mb. Validation of the model was carried out by comparing predicted and analysed Fe pool sizes in erythrocytes, the liver and the spleen. Body adiposity was negatively associated with serum Fe levels and positively associated with liver Fe stores. An inferred increase in Fe transfer from bone marrow to the liver paralleled higher hepatic Fe concentrations and ferritin heavy-chain mRNA levels in the HF diet-fed animals, suggesting that liver Fe accumulation occurred at least in part due to a favoured liver erythrocyte uptake. If this feeding condition was to be prolonged, impaired Fe decompartmentalisation may occur, ultimately resulting in dysmetabolic Fe overload.


  • IPEN-DOC 25779

    AZEVEDO, JULIANA de S.; QUINTINO, MARILIA T.A.; ROGERO, SIZUE O. ; ZAMPIERI, MARIA C.T. ; ROGERO, JOSE R. . Histopathological changes in zebrafish exposed to sublethal concentrations of 89nm silver nanoparticles for application in environmental diagnostics. Human and Ecological Risk Assessment, v. 26, n. 5, p. 1207-1220, 2020. DOI: 10.1080/10807039.2018.1560219

    Abstract: The use of biomarkers as indicators of environmental contamination has been shown to be an excellent indicator of changes in biota. Histopathological lesions are commonly used in biomonitoring studies as they provide information regarding both acute and chronic exposure. The use of nanoparticle materials has been widespread in recent years. However, not much is known about their ecological effects on the natural environment. Thus, the aim of this study was to assess the sublethal effects of silver nanoparticles (AgNP) with mean diameters of 89nm in the zebrafish Danio rerio by the determination of the LC50; 48 h and histopathological assays in gills. The obtained LC50; 48 h was 8.18 mgL 1. The histopathological gill assessment showed primary responses indicative of acute damage as aneurysms (32.76%), hyperplasia (20.69%) and partial (30.17%) and total lamellar fusion (6.9%) of secondary lamellae. No deposition of AgNP was observed in any tested sample gills, suggesting other organs target to absorption and detoxification. In fact, the AgNP causes sublethal damage in the gills of zebrafish but is not able to accumulate in this tissue. Finally, the data shown in this study contribute to the construction of a database on the AgNP exposure in aquatic organisms.


  • IPEN-DOC 25761

    BOIDI, G.; TERTULIANO, I.S.; PROFITO, F.J.; ROSSI, W. de ; MACHADO, I.F.. Effect of laser surface texturing on friction behaviour in elastohydrodynamically lubricated point contacts under different sliding-rolling conditions. Tribology International, v. 149, p. 1-9, 2020. DOI: 10.1016/j.triboint.2019.02.021

    Abstract: The Laser Surface Texturing (LST) technique has been largely investigated to improve the tribological performance of lubricated contacts. The present contribution is aimed at scrutinizing the influence of three texture configurations fabricated by LST on the tribological performance of elastohydrodynamic (EHD) point contacts under different slide-to-roll ratios (SRR), entrainment velocities and inlet temperatures. Friction experiments were conducted through a series of ball-on-disk tests in the MTM-2 (Mini-Traction Machine) tribometer. Main results showed that the texture configurations promoted significant effects under boundary and mixed lubrication conditions, and also affected the full-film EHD regime at higher temperatures. Furthermore, the tribological performance of textured samples was strongly related to the texture depth. Shallower texture designs (∼0.5 μm) reduced friction compared to untextured material, whereas deeper features (> 1 μm) generally led to detrimental results. In general, dimples configuration decreased the lift-off speed and promoted full-film EHD conditions for a larger range of speeds, whereas radial curved grooves yielded to friction reduction under mixed lubrication conditions, moving the transition from boundary to mixed regimes to lower speeds, especially for intermediate lubricant viscosity.


  • IPEN-DOC 26989

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

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


  • IPEN-DOC 26948

    LÉPINE-SZILY, A.; LEISTENSCHNEIDER, E.; DESCOUVEMONT, P.; MENDES JUNIOR, D.R.; LICHTENTHÄLER, R.; ALVAREZ, M.A.G.; PAMPA CONDORI, R.; FARIA, P.N. de; PIRES, K.C.C.; SCARDUELLI, V.; ZAGATTO, V.A.B.; DESMUKH, N.; MORCELLE, V.; MORAIS, M.C.; SHORTO, J.M.B. ; GUIMARÃES, V.; ASSUNÇÃO, M.. Study of high lying resonances in 9Be by the measurement of (p,p), (p,a) and (p,d) reactions. Proceedings of Science, v. 281, n. 223, p. 1-8, 2017. DOI: 10.22323/1.281.0223

    Abstract: The (p, p), (p, a) and (p, d) reactions on 8Li were measured at low energies. The experiment was performed using a thick [CH2]n target and a radioactive 8Li beam available at the RIBRAS facility of São Paulo . This experiment represents an upgrade of a previous experiment, where only the 8Li(p,a)5He cross section was measured. High lying resonances of 9Be, which are still uncertain, could be studied in this way. The detection of several reaction channels allows a reliable determination of the resonance parameters, such as energy, width and spin-parity. In the deuteron channel we could observe the same resonance decaying to d+7Ligs and to d+7Li∗. The properties of the resonances are determined by a R-matrix analysis, which provides evidence for a significant clustering as well in the (p, a) as in the (p, d) channels. The experimental data and the multi-channel R-matrix analysis will be presented.


  • IPEN-DOC 26935

    STELLATO, THAMIRIS B. ; SILVA, TATIANE B.S.C. da ; VILLA, SABRINA M. ; MARQUES, JOYCE R. ; FAUSTINO, MAINARA G. ; SILVA, DOUGLAS B. da ; MONTEIRO, LUCILENA R. ; IZIDORO, JULIANA C. ; COTRIM, MARYCEL E.B. ; PIRES, MARIA A.F. . A avaliação da eficiência da zeólita na remoção do íon amônio numa solução sintética. Revista Banas Qualidade, v. 24, n. 272, p. 85-89, 2015.

    Abstract: A proposta deste estudo é avaliar a eficiência da zeólita na remoção do íon amônio numa solução sintética, para sua posterior aplicação em sistemas de tratamentos de efluentes.

    Palavras-Chave: zeolites; ions; removal; ammonia; chemical composition; chemical effluents; liquid wastes; waste processing; ammonium compounds


  • IPEN-DOC 26934

    CABRAL, FERNANDA V. ; SILVA, CAMILA R. ; SAUTER, ISMAEL P.; SABINO, CAETANO P. ; YOSHIMURA, TANIA M. ; CORTEZ, MAURO; RIBEIRO, MARTHA S. . Efeito da terapia fotodinâmica no tratamento de leishmaniose cutânea em um modelo murino. Anais da SBBN, v. 3, p. 67-77, 2016.

    Abstract: Leishmanioses são doenças parasitárias desenvolvidas por protozoários do gênero Leishmania. A forma cutânea abrange lesões destrutivas e ulceradas com diversas limitações no tratamento. Terapias alternativas são fundamentais devido à grande relevância da doença e elevada incidência. Nesse contexto, a terapia fotodinâmica (PDT) tem sido introduzida devido ao baixo custo, baixa toxicidade, praticidade e sem relatos de resistência na literatura. Neste trabalho, dezesseis camundongos BALB/c foram infectados com 1.106 parasitos de Leishmania(L) amazonensisno membro posterior esquerdo e acompanhados por 4 semanas até o surgimento da lesão. Após esse período, os animais foram submetidos à PDT usando um diodo emissor de luz (λ=660 ±22 nm) e azul de metileno (100 μM), com fluências de 50, 100 e 150J/cm² e acompanhados durante 3 semanas. Animais controle não receberam tratamento. O tamanho da lesão e escala de dor foram mensurados utilizando um paquímetro e filamentos von Frey, respectivamente. A quantificação da carga parasitária foi realizada através do método de diluição limitante. Os resultados demonstraram que, nas semanas 2 e 3 após tratamento, ocorreu diminuição da lesão e alívio de dor nos animais que receberam 150J/cm², sugerindo que a PDT promoveu melhora clínica através da modulação do processo inflamatório.

    Palavras-Chave: photosensitivity; methylene blue; parasites; parasitic diseases; biological models; epithelium; light sources; light emitting diodes; therapy; skin diseases


  • IPEN-DOC 26929

    MORENO, CAROLINA S. ; ROGERO, SIZUE O. ; GALISTEO JUNIOR, ANDRES J.; VIEIRA, DANIEL P. ; CRUZ, AUREA S.; SAKURABA, ROBERTO K.; WELTMAN, EDUARDO; ROGERO, JOSE R. . Analysis of the combined effects of resveratrol and radiation on lung cancer cells. Integrative Cancer Biology & Research, v. 1, n. 1, 2017.

    Abstract: Mucoepidermoid lung carcinoma is frequently manifested by obstructive trachea symptoms. It is necessary to develop effective curative or palliative therapeutic strategies for treating mucoepidermoid lung carcinoma through administration of compounds that improve ionizing radiation treatment, thereby increasing the effects of the treatment on tumor cells while minimizing the effects on normal tissues surrounding the tumor cells. Resveratrol is a polyphenolic phytoalexin present in wines and several plants and has a broad spectrum of biological activities, including antioxidant and anticarcinogenic effects. The biological effects of ionizing radiation plus resveratrol have been examined in different types of cell in many studies. Here, we aimed to verify the effects of resveratrol on mucoepidermoid lung carcinoma cells NCI-H292 exposed to ionizing radiation. In vitro studies in NCI-H292 cell culture using neutral red uptake assays showed that the cytotoxicity index (IC50) of resveratrol was 401.5μM, and the lethal dose 50 % (LD50) of ionizing radiation in the absence of resveratrol was 693 Gy. In vitro micronucleus assays were then performed to verify the genotoxic effects of resveratrol, and fluorescence assays were performed to evaluate the effects of resveratrol on the cell cycle, repair and injury processes, cellular necrosis, and apoptosis. The results demonstrated that 30μM resveratrol promote injury on NCI-H292 cells after 24 h of irradiation. Therefore, this study provides results able to support in vitro future investigations about radiosensitive potential of resveratrol in lung cancer cells. There is a need to investigate compounds with potential to improve the local control of lung cancer promoted by radiation therapy. This way avoiding injuries to healthy cells.

    Palavras-Chave: dna damages; in vitro; ionizing radiations; lungs; lymphokines; neoplasms; polyphenols; radiation effects; radiosensitivity


  • IPEN-DOC 26928

    SANTOS, A.S.; BITTENCOURT, C.. Depollution of rivers and lakes. European Journal of Sustainable Development, v. 6, n. 3, p. 430-438, 2017. DOI: 10.14207/ejsd.2017.v6n3p430

    Abstract: The need to control pollution is a relevant environmental issue in Brazil, and in the world. Population growth demands a greater exploitation of natural resources, in many cases, above the natural recovery capacity of ecosystems. The decontamination of a river or lake involves, among other forms of intervention, the management of sanitation services, thus allowing the qualitative improvement of water resources. The progressivity of the supply of sanitation infrastructure will allow the attendance of the regular areas with collection and treatment of sewage. On the other hand, in order to achieve their goals, it is also necessary to address the social issue, the precarious housing, and especially the irregularly settled ones, which demand greater efforts to provide sanitation services.

    Palavras-Chave: lakes; rivers; water pollution; water pollution monitors; liquid wastes; water treatment; waste management; pollution laws; legislation; environment; brazil


  • IPEN-DOC 26927

    YATACO-LAZARO, LOURDES M.; GONZALEZ-RUIZ, JESUS; VIRGINIO, SUELI ; OLIVEIRA, RENE R. ; MAIA, WILSON S.; VALENZUELA-DIAZ, FRANCISCO; MOURA, ESPERIDIANA . Efecto morfológico y térmico de filmes flexibles de etilen vinil alcohol reforzados con óxido de grafeno / Morphological and thermal effects of ethylene vinyl alcohol film reinforced with graphene oxide. Revista ECIPerú, v. 12, n. 2, p. 5-9, 2015.

    Abstract: Se estudió los efectos morfológicos y térmicos de los filmes de EVOH reforzados con 0.1 y 0.5 wt. % de GO. El EVOH ha sido ampliamente usado en embalajes para alimentos porque preserva la calidad de los productos debido a su excelente desempeño de barrera de gas y su buena transparencia. El GO fue preparado vía oxidación química del grafito y fue exfoliado en nanoláminas usando el método sonoquímico. Los filmes fueron preparados por extrusión en estado fundido y extrusión por soplado, luego fueron caracterizados por análisis de XRD, TG y SEM, la correlación entre sus propiedades fue discutida.

    Palavras-Chave: films; temperature dependence; ethylene; alcohols; packaging; food; graphene; oxides; mechanical properties


  • IPEN-DOC 26926

    CAZULA, C.D. ; CAMPOS, M.P. ; MAZZILLI, B.P. . Calibração de detectores sólidos de traços nucleares do tipo CR-39 para medidas de Rn-222 no ar. Brazilian Journal of Radiation Sciences, v. 3, n. 1A, p. 1-8, 2015. DOI: 10.15392/bjrs.v3i1A.174

    Abstract: No método de detecção com detectores sólidos de traços nucleares, quando uma partícula pesada incide sobre a superfície do detector, provoca um desarranjo em sua estrutura molecular formando um traço. Uma das aplicações mais comuns desses detectores está na medição da concentração de Rn-222 no ar, um gás nobre radioativo, membro da série do U-238, emissor de partículas alfa e importante em estudos epidemiológicos para proteção dos indivíduos à radiação natural. Para determinar a concentração de Rn-222 no ar em um ambiente é necessário conhecer a densidade de traços (traços/cm2) na superfície do detector, o tempo de exposição e o fator de calibração. A determinação do fator calibração para os detectores CR-39 foi feita a partir da exposição destes a uma concentração conhecida de Rn-222. Para tanto, os detectores foram inseridos no interior de uma célula de Lucas adaptada e posteriormente expostos a uma concentração de Rn-222 de 15 kBq/m3, por meio do aparelho RN-150 da Pylon Eletronics Incorporation, que possui uma fonte de Ra-226 e libera concentrações conhecidas de Rn-222. Foram realizadas seis determinações do fator de calibração, o valor médio obtido foi de 0,0534 ± 0,0021 (traços/cm2 por Bq/m3 dia). Os resultados são compatíveis com os valores da literatura para o mesmo tipo de detector e apresentaram boa reprodutibilidade.

    Palavras-Chave: calibration; concentration ratio; experimental data; optical microscopy; particle tracks; radiation detectors; radiation sources; radon 222; radon 226


  • IPEN-DOC 26925

    PIRES, JULIANA A. ; LIMA, DAMARIS C.; SILVA, LUCIA C.A.S.; ARTHUR, VALTER; HARDER, MARCIA N.C.. Efeitos da irradiação (Co60) nas propriedades físico-químicas de batata minimamente processada / Effects of irradiation (Co60) on the physical-chemical properties of minimally processed potato. Brazilian Journal of Food Research, v. 8, n. 1, p. 72-79, 2017. DOI: 10.3895/rebrapa.v8n1.3721

    Abstract: A batata (Solanum tuberosum L.) é um tubérculo que possui qualidades nutritivas e por adaptar-se facilmente a vários tipos de solo, seu consumo generalizou-se em todo o mundo. A irradiação nos últimos anos está sendo utilizada como alternativa no aumento de vida útil de vários alimentos, portanto esse trabalho objetivou avaliar o efeito da radiação gama na conservação de batatas-inglesas minimamente processadas. As batatas foram higienizadas, e minimamente processadas e embaladas a vácuo e posteriormente irradiadas em dose de 0; 1; 2; 3kGy. Foram realizadas análises físico-químicas de pH, acidez, sólidos solúveis e firmeza. Como resultado obteve-se os melhores resultados nas amostras irradiadas à 1kGy, pois apresentou valores próximos aos da testemunha nos parâmetros avaliados, além do maior valor de firmeza, características estas desejáveis em produtos minimamente processados. Conclui-se que o efeito da radiação na dose de 1kGy foi adequado no tratamento de batatas-inglesas minimamente processadas.

    Palavras-Chave: potatoes; physical properties; chemical properties; gamma radiation; food processing; cobalt 60; irradiation; radiation effects; brazil


  • IPEN-DOC 26924

    MACHI, ANDRE R. ; HARDER, MARCIA N.C.; ARTHUR, PAULA B. ; FRANCO, SUELY S.H.; ARTHUR, VALTER . Ionizing radiation and the influence of package to control of Sitophilus oryzae in rice. Australian Journal of Basic and Applied Sciences, v. 11, n. 15, p. 71-75, 2017. DOI: 10.22587/ajbas.2017.11.15.10

    Abstract: Objective: This study aimed to use the gamma radiation from Cobalt-60 to control of Sitophilus oryzae in package with previously infested rice and artificial reinfestation. Material and Methods: In the research, 3 types of sample were used: 2 commercial rice packages and 1 in crystal sugar packages. The samples were irradiated with a dose of 1.0kGy to promote disinfestations under a dose rate of 0.560 Gy/h. After 60 days were counted the number of live and dead insects in each package. Results: We concluded that the package containing holes for gases exchange from inside to outside of the package showed easily penetration of insects, while the two packages without holes prevented the reinfestation of insects. Conclusion: The dose of 1.0 kGy was sufficient to do the disinfestations of rice.

    Palavras-Chave: irradiation; ionizing radiations; packaging; cobalt 60; rice; pest control; insects; storage life; gamma radiation; dose rates; disinfestation


  • IPEN-DOC 26923

    VECCHIO, DANIELA; GUPTA, ASHEESH; HUANG, LIYI; LANDI, GIACOMO; AVCI, PINAR; RODAS, ANDREA ; HAMBLIN, MICHAEL R.. Bacterial photodynamic inactivation mediated by methylene blue and red light is enhanced by synergistic effect of potassium iodide. Antimicrobial Agents and Chemotherapy, v. 59, n. 9, p. 5203-5212, 2015. DOI: 10.1128/AAC.00019-15

    Abstract: The inexorable increase of antibiotic resistance occurring in different bacterial species is increasing the interest in developing new antimicrobial treatments that will be equally effective against multidrug-resistant strains and will not themselves induce resistance. One of these alternatives may be photodynamic inactivation (PDI), which uses a combination of nontoxic dyes, called photosensitizers (PS), excited by harmless visible light to generate reactive oxygen species (ROS) by type 1 (radical) and type 2 (singlet oxygen) pathways. In this study, we asked whether it was possible to improve the efficacy of PDI in vitro and in vivo by addition of the inert salt potassium iodide (KI) to a commonly investigated PS, the phenothiazinium dye methylene blue (MB). By adding KI, we observed a consistent increase of red light-mediated bacterial killing of Gram-positive and Gram-negative species in vitro and in vivo. In vivo, we also observed less bacterial recurrence in wounds in the days posttreatment. The mechanism of action is probably due to formation of reactive iodine species that are produced quickly with a short lifetime. This finding may have a relevant clinical impact by reducing the risk of amputation and, in some cases, the risk of death, leading to improvement in the care of patients affected by localized infections.

    Palavras-Chave: bacteria; inactivation; photosensitivity; methylene blue; potassium iodides; in vivo; in vitro; antibiotics; drugs; light sources; therapy; reagents


  • IPEN-DOC 26922

    KIBRIT, EDUARDO ; AQUINO, AFONSO R. de ; MELLO, ADRIANA M. de; NASCIMENTO, PAULO T. de S.. Sustainable operations in nuclear research reactors: a bibliographical study. atw - International Journal for Nuclear Power, v. 62, n. 10, p. 589-596, 2017.

    Palavras-Chave: bibliographies; radioactive waste management; reactor operation; recycling; research reactors; sustainability; document types; management; operation; reactor life cycle; reactors; research and test reactors; waste management


  • IPEN-DOC 26921

    KONIGAME, VIVIAN C.; CONTI, THADEU das N. . Estudo do reator nuclear de 4ª geração “Very High Temperature Reactor” – VHTR / Study of nuclear reactor of 4th generation “Very High Temperature Reactor” – VHTR. Revista Engenharia e Tecnologia Aplicada - UNG, v. 1, n. 1, p. 47-68, 2017.

    Abstract: Como resultado do crescimento populacional e desenvolvimento da economia há uma demanda maior por energia, sendo necessário diversificar suas fontes de geração, sem causar aumento dos impactos negativos ao meio ambiente. Atualmente, há diversas fontes de geração de energia (combustíveis fósseis, renováveis, nuclear etc). A energia gerada por reatores nucleares é segura, e apresenta vantagens econômicas e ambientais e, por isso, está sendo considerada uma opção viável para geração de energia no futuro. Há diversas gerações de sistemas de reatores nucleares, sendo que no presente trabalho será estudado o reator de geração-IV, “Very-High-Temperature Reactor” (VHTR). O VHTR é um reator térmico, moderado a grafite, refrigerado a hélio, e com um ciclo aberto para o urânio. É seguro e eficiente na cogeração de hidrogênio e eletricidade, e pode reduzir a dependência das reservas de combustíveis fósseis, a emissão de gases nocivos ao meio ambiente e a poluição.

    Palavras-Chave: reactors; nuclear energy; temperature range 1000-4000 k; hydrogen; thermal reactors; nuclear fuels; environmental impacts; energy source development; carbon


  • IPEN-DOC 26920

    CAVINATO, C.C. ; ANDRADE, D.A. ; DIZ, M.D.P.E.; SABUNDJIAN, G. . Levantamento bibliográfico sobre metodologias para elaboração de um banco de dados da saúde da população em casos de ocorrências de câncer. Brazilian Journal of Radiation Sciences, v. 3, n. 1A, p. 1-14, 2015. DOI: 10.15392/bjrs.v3i1A.79

    Abstract: As fontes alternativas de energia, incluindo a nuclear, apresentam vantagens com relação às externalidades, as quais podem ser identificadas e relacionadas com o termo, custo ambiental. Este termo, por sua vez, é uma externalidade negativa, que de alguma forma prejudica o meio ambiente e é convertida em termos econômicos, para então poder ser comparada aos demais custos de uma ação e/ou empreendimento. A fim de efetuar os cálculos em questão, são utilizados alguns softwares específicos, os quais possibilitam a conversão dos danos em termos econômicos e a inclusão do custo ambiental na análise de custo de determinado projeto. Uma das dificuldades encontradas na utilização destes softwares tem sido com relação a alguns dados de entrada, como por exemplo, os relativos à saúde da população em torno da instalação nuclear, que são muito deficientes. O objetivo deste trabalho é fazer um levantamento teórico correspondente às metodologias existentes e utilizadas para a elaboração de banco de dados de saúde pública no Brasil. A partir das metodologias encontradas para a formação deste tipo de banco de dados, posteriormente será desenvolvida uma metodologia focando na saúde (câncer fatal e não fatal) da população circunvizinha a uma instalação nuclear, para fins de cálculo do custo ambiental da mesma. Essa será aplicada ao público interno do Instituto de Pesquisas Energéticas e Nucleares (IPEN), como um pré-teste, para aquisição das informações de saúde desejadas.

    Palavras-Chave: computer codes; data acquisition; information; neoplasms; nuclear facilities; public health; brazilian organizations; data processing; diseases; national organizations; processing; brazilian cnen


  • IPEN-DOC 26919

    EGGERT, B.G.F.; TEIXEIRA, C.S.; LOPES, L.U. ; WENDHAUSEN, P.A.P.. Feasibility of Nd substitution in (La, Nd)(Fe, Si)13 magnetocaloric compound obtained by the reduction-diffusion process. IEEE Transactions on Magnetics, v. 52, n. 5, 2016. DOI: 10.1109/TMAG.2015.2512502

    Abstract: Quaternary magnetocaloric compound La1−xNdxFe11.3Si1.7 was synthesized via the so-called reduction–diffusion (RD) process. The RD process was carried out at 1423 K, using Ca as the reducing agent and La and Nd oxides as the precursors to form, together with iron and silicon powder, the desired cubic NaZn13-type structure. The main purpose was to study the interchange of La and Nd in terms of process yield, crystal structure parameters and typical magnetic transition temperature [Curie temperature (Tc)] associated with the magnetocaloric effect. Microstructural characterization by scanning electron microscopy associated with microprobe energy dispersive spectroscopy and backscattered electron imaging was used to identify morphology and particle size of reaction products, as well as the extent of diffusion reactions. Structural characterization results obtained by X-ray diffraction technique associated with Rietveld refinements show the possibility to obtain almost single-phase La1−xNdxFe11.3Si1.7, for which x was varied from 0 to 0.5, with reminiscent α-iron phase below 10 wt%. Moreover, the Tc of all obtained alloys were inferred from differential scanning calorimetry curves, showing that Nd is an effective alloying element to tune the working temperature in the near-room-temperature magnetic refrigeration.

    Palavras-Chave: neodymium compounds; feasibility studies; intermetallic compounds; magnetic properties; reduction; microstructure; x-ray diffraction; magnetic fields; regenerators; magnetic properties


  • IPEN-DOC 26917

    ARTHUR, VALTER ; GUEDES, ELIANE D.F. da S.; SILVA, LUCIA C.A.S.; PIRES, JULIANA A. ; HARDER, MARCIA N.C.; FRANCO, SUELY S.H. ; ARTHUR, PAULA B. ; FRANCO, CAMILO F. de O.; CAZE FILHO, JORGE. Efeitos da radiação gama nas características físico-químicas do arroz pré-cozido / Effects of gamma irradiation on the physicochemical characteristics of pre-cooked rice. Revista Tecnologia & Ciência Agropecuária, v. 10, n. 6, p. 83-86, 2016.

    Abstract: A pesquisa teve como objetivo avaliar os efeitos da radiação gama nas características físico-químicas do arroz pré-cozido como um método de conservação. A pesquisa foi realizada no laboratório de Radiobiologia e Ambiente do Centro de Energia Nuclear na Agricultura –CENA/USP, Piracicaba, SP., Brasil.As amostras foram irradiadas com doses de:0(controle); 1,0; 2,0; e 3,0 kGy, em um irradiador de Cobalto-60, tipo Gammacell-220, sob uma taxa de dose de 0,256 kGy/hora. Após a irradiação foram realizadas análises físicas químicas das amostras irradiadas e do controle. Para a analise dos resultados foi utilizado teste de Tukey (p ≤ 0,05) para verificar as diferenças estatísticas entre os tratamentos. Pelos resultados concluiu-se que o processo de irradiação na dose de 3 kGy pode ser utilizado na conservação das propriedades do arroz pré-cozido.

    Palavras-Chave: gamma radiation; cereals; rice; food processing; qualitative chemical analysis; cobalt 60; gravimetric analysis; irradiation; gamma sources


  • IPEN-DOC 26916

    MONTEIRO, LUCILENA R. ; PORFIRIO, DARILENA M.; VILLA, SABRINA M. ; MARQUES, JOYCE R. ; FAUSTINO, MAINARA G. ; COTRIM, MARYCEL E.B. ; PIRES, MARIA A.F. . Implantação de controles de qualidade internos e externos em laboratórios de ensaios químicos. Jornal da Metrologia, 2015.

    Palavras-Chave: quality control; materials testing; testing; quality assurance; chromatography; anions; abundance; chemical analysis; chemical properties


  • IPEN-DOC 26915

    MAZIERO, JOANA da S. ; ROGERO, SIZUE O. ; ALEMANY, ADAIR. Estudo ecotoxicológico da nanopartícula de prata em Daphnia similis / Ecotoxicological study of silver nanoparticle on Daphnia similis. Journal of the Health Sciences Institute - Revista do Instituto de Ciências da Saúde, v. 34, n. 3, p. 133-139, 2016.

    Abstract: Objetivo –Verificar a toxicidade da NPAg em organismos aquáticos por meio do ensaio de ecotoxicidade aguda. O aumento na produção e utilização das nanopartículas de prata (NPAg) em diversas áreas, tem provocado preocupação quanto aos impactos e riscos potenciais que estas podem causar ao meio ambiente. Métodos – O teste de ecotoxicidade aguda foi realizado seguindo a Norma Brasileira ABNT NBR 12713, utilizando como organismo-teste a Daphnia similis. A exposição dos organismos ocorreu em cinco concentrações de NPAg, durante 48 horas. O resultado de CE50, concentração do agente tóxico que causa imobilidade a 50% dos organismos expostos, da NPAg foi obtida pelo método estatístico de Trimmed Spearman-Karber. Resultados – A média da CE50 da NPAg obtidas nos três ensaios realizados foi de 4,70 μg L–1. Conclusão – De acordo com os resultados obtidos, a NPAg causou imobilidade a 50% dos organismos expostos na concentração de 4,70 μg L–1. Estudos devem ser continuados para melhor esclarecimento dos impactos no meio ambiente aquático.

    Palavras-Chave: aquatic ecosystems; toxicity; silver; nanoparticles; metals; daphnia; aquatic organisms; crustaceans; chemical analysis; physical chemistry; toxic materials


  • IPEN-DOC 26909

    RIBEIRO, ANDREZA P. ; FIGUEIREDO, ANA M.G. ; SANTOS, JOSE O. dos; FERREIRA, PAULO A. de L.; GRAUDENZ, GUSTAVO S.; RUIZ, MAURO S.; MAHIQUES, MICHEL M. de; FIGUEIRA, RUBENS C.L.; WASSERMAN, JULIO C. de F.A.. Effects of contamination with toxic metals on the environmental quality of Sepetiba Bay (SE Brazil): The case of Ingá Company. Management of Environmental Quality, v. 26, n. 4, p. 538-551, 2015. DOI: 10.1108/MEQ-06-2013-0074

    Abstract: Purpose – The purpose of this paper is to address the case of toxic metal contamination of Sepetiba Bay caused by the Ingá Company. The paper reviews the history of the contamination and discusses the current presence of metals in the bay sediments, demonstrating that the toxic metals are clearly enriched. Sepetiba Bay is prone to significant dredging activities that make metals available in the food chain, affecting human populations, mainly fishermen communities. Design/methodology/approach – The study presents the case of the Ingá Company based on international literature and data provided by previous studies. Findings – Through the analysis and compilation of diverse data from the literature, this study demonstrates that the Ingá Company is a major source of Cd, Pb and Zn due to its calamine processing activities used to obtain high purity Zn. Originality/value – This study highlights important research to complete the historical scenario of heavy metal contamination of the Sepetiba Bay by Ingá Company. The results indicate that the contaminants from the Ingá Company can indeed be traced in the sediments of Sepetiba Bay. These data have the utmost value for the environmental management of this coastal system, because such high concentrations of toxic metals in marine sediments have serious implications for the environmental quality of the bay and may negatively affect biota and human health. Therefore, this study suggests that it is now necessary to monitor this region for contamination continuously.

    Palavras-Chave: pollution; water pollution monitors; concentration ratio; environmental impacts; metals; toxic materials; toxicity; environmental impacts; bays; brazil; environmental quality; water quality


  • IPEN-DOC 26908

    SILVA, L.F.F.L. da ; ZAMBONI, C.B. ; BAHOVSCHI, V. ; METAIRON, S. ; SUZUKI, M.F. ; SANTANNA, O.A.; RIZZUTTO, M.A.. Determination of inorganic elements in blood of mice immunized with Bothrops Snake venom using XRF and NAA. Journal of Physics: Conference Series, v. 630, p. 1-6, 2015. DOI: 10.1088/1742-6596/630/1/012005

    Abstract: In this work, mice genetically modified [HIII line] were immunized against different Bothrops snake venoms to produce anti-Bothrops serum (antivenom). The Neutron Activation Analysis (NAA) and Energy Dispersive X-Ray Fluorescence (EDXRF) techniques were used to evaluate Ca and Fe concentrations in blood of these immunized mice in order to establish a potential correlation between both phenotypes: antibody response and blood constituents after Bothrops venom administration. The results were compared with the control group (mice not immunized) and with human being estimative. These data are important for clinical screening of patients submitted to immunological therapy as well as the understanding of the envenoming mechanisms.

    Palavras-Chave: antibodies; blood; calcium; comparative evaluations; concentration ratio; correlations; fluorescence; iron; mice; neutron activation analysis; patients; phenotype; screening; snakes; therapy; venoms; x radiation; x-ray fluorescence analysis


  • IPEN-DOC 26907

    MIRANDA, LEILA F. de; GOULART, LEID J.P.; SILVA, LEONARDO G. de A. e ; DONADON, ALEXANDRE C.; YAMASAKI, FABIO Y.; MUNHOZ JUNIOR, ANTONIO H.. Characterization of polystyrene nanocomposites containing nanoparticles of pseudoboehmite obtained by sol-gel process. Journal of Nano Research, v. 47, p. 96-105, 2017. DOI: 10.4028/

    Abstract: Polymeric nanocomposites are hybrid materials in which inorganic substances of nanometric dimensions are dispersed in a polymeric matrix. These inorganic substances have high surface area allowing a better interaction with the polymeric matrix and consequently promote changes in the physical properties of the final composite with small additions of the same. The preparation of nanocomposites with polymer matrix allows in many cases to find a relationship between a low cost due to the use of lower amount of charge, reaching high level of performance. In this work, it was obtained polystyrene nanocomposites with pseudoboehmite synthesized by the solgel process with different concentrations of pseudoboehmite using and not using octadecylamine as a coupling agent. The nanocomposites were prepared by the melt intercalation technique. The pseudoboehmite nanoparticles were characterized by X-ray diffraction, scanning electron microscopy, differential thermal analysis and thermo gravimetric analysis. The nanocomposites were characterized by differential thermal analysis, thermogravimetric analysis, heat deflection temperature, Vicat softening point, mechanical and rheological tests. The results showed an increase in the thermal properties, hardness and tensile strength values and decrease in the melt index, impact resistance and tensile elongation, showing the interaction of the filler with the polymer matrix. Although in the samples with the presence of octadecylamine the data shows that the thermomechanical properties practically do not vary in relation with the samples without octadecylamine.

    Palavras-Chave: polystyrene; nanocomposites; polymerization; sol-gel process; aluminium oxides; amines; thermal gravimetric analysis; synthesis


  • IPEN-DOC 26906

    ISAAC, CESAR; MATHOR, MONICA B. ; TEODORO, WALCI; CARVALHO, VIVIANE F. de; GEMPERLI, ROLF; PAGGIARO, ANDRE de O.. Avaliação microscópica de técnicas de desepitelização de membranas amnióticas gliceroladas / Microscopic evaluation of deepithelization techniques of glycerolated amniotic membrane. Revista Saúde - UNG, v. 10, n. 3-4, p. 22-33, 2016.

    Abstract: Introdução: A membrana amniótica (MA) é considerada um biomaterial com propriedades biológicas benéficas ao processo de reparação tecidual servindo também como substrato para o cultivo de células epiteliais. Objetivo: estabelecer um método de desepitelização amniótica que preserve a membrana basal. Método: Foram testados 7 tipos diferentes de desepitelização enzimática de membranas amnióticas gliceroladas, avaliando-se cada um por microscopia óptica e posteriormente, por microscopia eletrônica. Resultado: A exposição das membranas à Tripsina 0,05%/EDTA 0,02% por 20 minutos permitiu a completa retirada epitelial com a menor delaminação quando comparado aos outros métodos testados. A microscopia eletrônica evidenciou que após desepitelizacão com Tripsina 0,05%/EDTA 0,02% por 20 minutos a membrana basal permanecia íntegra. Conclusão: Tripsina 0,05%/EDTA 0,02% por 20 minutos permite completa desepitelização das MAs com preservação da membrana basal.

    Palavras-Chave: fetal membranes; embryonic cells; cell membranes; cell cultures; glycerol; epithelium; basements; evaluation; optical microscopy


  • IPEN-DOC 26905

    GALIZONI, BRENO B.; COUTO, ANTONIO A. ; REIS, DANIELI A.P.. Heat treatments effects on nickeI-based superalloy Inconel 713C. Defect and Diffusion Forum, v. 390, p. 32-40, 2019. DOI: 10.4028/

    Abstract: The purpose of this work is to study the effect of heat treatments on the microstructure of the nickel-based superalloy Inconel 713C. Three different conditions were studied and the results compared: (1) as cast; (2) solution treatment (1,179°C/2h) and (3) stabilizing treatment (1,179°C/2h plus 926°C/16h). Inconel 713C is normally used in the as-cast condition, an improvement in the 980°C stress-rupture life is often obtained by a solution heat treatment. However, the material in this condition tested under high stress at 730°C shows a marked decreased in rupture life and ductility [1]. The mechanical resistance in creep increases in Inconel 713C by precipitation hardening phase, such γ’ (Ni3Al) formed during the heat treatments [2]. The characterization techniques used was: chemical analysis, hardness test, X-ray diffraction, optical microscope and scanning electron microscopy (SEM), EDS analyzes and thermocalculation. The heat treatments modified the dendritic structure, reducing the acicularity. The SEM and EDS analysis illustrated the γ, γ’ and carbides. The matrix phase (γ), has in its constitution the precipitation of the γ’ phase, in a cubic form, and in some regions, veins of carbides were modified with the heat treatments.

    Palavras-Chave: heat treatments; alloys; inconel 713c; microstructure; nickel base alloys; chemical analysis; mechanical properties


  • IPEN-DOC 26892

    ALIBHAI, A.Y.; PRETTO, LUCAS R. de ; MOULT, ERIC M.; OR, CHRIS; ARYA, MALVIKA; MCGOWAN, MITCHELL; CARRASCO-ZEVALLOS, OSCAR; LEE, BYUNGKUN; CHEN, SIYU; BAUMAL, CAROLINE R.; WITKIN, ANDRE J.; REICHEL, ELIAS; FREITAS, ANDERSON Z. de ; DUKER, JAY S.; FUJIMOTO, JAMES G.; WAHEED, NADIA K.. Quantification of retinal capillary nonperfusion in diabetics using wide-field optical coherence tomography angiography. RETINA, The Journal of Retinal and Vitreous Diseases, v. 40, n. 3, p. 412-420, 2020. DOI: 10.1097/IAE.0000000000002403

    Abstract: Purpose: To combine advances in high-speed, wide-field optical coherence tomography angiography (OCTA) with image processing methods for semiautomatic quantitative analysis of capillary nonperfusion in patients with diabetic retinopathy (DR). Methods: Sixty-eight diabetic patients (73 eyes), either without retinopathy or with different degrees of retinopathy, were prospectively recruited for volumetric swept-source OCTA imaging using 12 mm · 12 mm fields centered at the fovea. A custom, semiautomatic software algorithm was used to quantify areas of capillary nonperfusion. Results: The mean percentage of nonperfused area was 0.1% (95% confidence interval: 0.0–0.4) in the eyes without DR; 2.1% (95% confidence interval: 1.2–3.7) in the nonproliferative DR eyes (mild, moderate, and severe), and 8.5% (95% confidence interval: 5.0–14.3) in the proliferative DR eyes. The percentage of nonperfused area increased in a statistically significant manner from eyes without DR, to eyes with nonproliferative DR, to eyes with proliferative DR. Conclusion: Capillary nonperfusion area in the posterior retina increases with increasing DR severity as measured by swept-source OCTA. Quantitative analysis of retinal nonperfusion on wide-field OCTA may be useful for early detection and monitoring of disease in patients with diabetes and DR.

    Palavras-Chave: tomography; coherent radiation; optical activity; optical properties; computerized tomography; ischemia; retina; diabetes mellitus; patients; perfused organs; capillaries; statistical data


  • IPEN-DOC 26673

    MANTECON, JAVIER G.; MATTAR NETO, MIGUEL . Numerical investigation on the effects of geometric deviations and materials properties on flow-induced deflections of fuel plates. Annals of Nuclear Energy, v. 140, p. 1-10, 2020. DOI: 10.1016/j.anucene.2019.107118

    Abstract: This work describes multiphysics analyses conducted to investigate the effect of geometric deviations and materials properties on flow-induced deflections of fuel plates. The analyzed configuration consists of two fuel plates and each one of them is bounded by two fluid channels. The fluid-dynamic forces acting on the plates are calculated using a Computational Fluid Dynamics model and the structural response is determined by means of a Finite Element Analysis model. Both models are coupled using the two-way fluid-structure interaction approach. The results show that manufacturing deviations from the nominal conditions and the increment of the system temperature lead to reduce the critical fluid velocity of the assembly.

    Palavras-Chave: fuel plates; geometry; mathematical models; fuel elements; research reactors; numerical analysis; physical properties


  • IPEN-DOC 26882

    TEIXEIRA, LUIZ F.S. ; PERON, JEAN P.S.; BELLINI, MARIA H. . Silencing of nuclear factor kappa b 1 gene expression inhibits colony formation, cell migration and invasion via the downregulation of interleukin 1 beta and matrix metallopeptidase 9 in renal cell carcinoma. Molecular Biology Reports, v. 47, n. 2, p. 1143-1151, 2020. DOI: 10.1007/s11033-019-05212-9

    Abstract: Renal cell carcinoma (RCC) is a highly deadly urological tumor due to its high metastatic incidence and its notorious chemoresistance. The nuclear transcription factor kappa B (NF-κB) family has been associated with apoptosis resistance and cellular invasion in RCC. The purpose of this study was to evaluate the impact of NF-κB1 gene silencing on the colony formation, cell migration and invasion abilities of the RCC cell line. Renca–mock and Renca-shRNA-NF-κB1 cells were used in this work. NF-κB1 downregulation was assessed by western blotting. The mRNA expression levels of interleukin-1 beta (IL-1β) and MMP-9 were assessed by real-time quantitative polymerase chain reaction (RT-qPCR). The IL-1β levels in the culture media were determined by a commercial ELISA kit. The MMP-9 protein expression and gelatinolytic activity were evaluated by western blotting and zymography, respectively, and the migration and invasion abilities were analysed. The expression levels of p105 and p50 in Renca-shRNA-NF-κBmoc1 cells were significantly reduced compared with those in the Renca–mock cells. The colony numbers of shRNA-NF-кB1 cells were lower than the colony numbers of the Renca– mock cells. NF-κB1 knockdown inhibited the cell migration and invasion of Renca-shRNA-NF-κB1 cells. These cells also exhibited reduced levels of IL-1β. The MMP-9 expression and activity levels were significantly reduced in Renca-shRNANF- κB1 cells. Taken together, these results indicate that the downregulation of NF-κB1 suppresses the tumourigenicity of RCC by reducing MMP-9 expression and activity; thus, NF-κB1 could be a molecular target for RCC treatment.

    Palavras-Chave: kidneys; carcinomas; transcription factors; colony formation; migration; carcinogenesis; transcription; transcription factors; antigens; proteins


  • IPEN-DOC 26876

    CORAZZA, FULVIO G.; ERNESTO, JULIA V.; NAMBU, FELIPE A.N.; CARVALHO, LUMA R. de ; LEITE-SILVA, VANIA R.; VARCA, GUSTAVO H.C. ; CALIXTO, LEANDRO A.; VIEIRA, DANIEL P. ; ANDREO-FILHO, NEWTON; LOPES, PATRICIA S.. Papain-cyclodextrin complexes as an intestinal permeation enhancer: permeability and in vitro safety evaluation. Journal of Drug Delivery Science and Technology, v. 55, p. 1-11, 2020. DOI: 10.1016/j.jddst.2019.101413

    Abstract: Oral drug delivery is the main route for drugs administration. However, some drugs have poor permeability across the intestinal barrier. Papain has been widely used in pharmaceutical applications due to its debridement properties and the ability to promote skin permeation of drugs. It is known that papain complexation with cyclodextrins improves its biological stability. In this paper, the ability of the native papain-cyclodextrin complexes is shown be an oral permeation enhancer to furosemide, using a Caco-2 monolayer system to evaluate drug permeability and apparent permeability coefficient. Analysis of the in vitro cytotoxicity over CHO–K1, Hep G2 and Caco-2 cell lines and genotoxicity over CHO–K1 and Hep G2 cell lines were also performed. Papaincyclodextrins complexes did not show any cytotoxicity above 31 μg/mL. No significant genotoxic damage was observed. Papain and cyclodextrin complexes induced almost 2.5-fold increase in furosemide permeation compared to controls, and maintenance of the paracellular integrity of the Caco-2 cells monolayer was confirmed. The papain complexes may be safely applied in pharmaceutical formulations, not only as a therapeutic agent but also as a strategic pharmaceutical adjuvant, promoting permeation of low oral permeability drugs.

    Palavras-Chave: papain; chelating agents; oligosaccharides; drugs; antimitotic drugs; enzymes; enzyme activity; membrane transport


  • IPEN-DOC 26666

    VEGA, L.E.R.; LEIVA, D.R.; LEAL NETO, R.M. ; SILVA, W.B.; SILVA, R.A.; ISHIKAWA, T.T.; KIMINAMI, C.S.; BOTTA, W.J.. Improved ball milling method for the synthesis of nanocrystalline TiFe compound ready to absorb hydrogen. International Journal of Hydrogen Energy, v. 45, n. 3, p. 2084-2093, 2020. DOI: 10.1016/j.ijhydene.2019.11.035

    Abstract: In this study, we propose a method to produce nanocrystalline TiFe powder by high-energy ball milling, in order to avoid the common sticking problem of the material to the milling tools, assuring a material prompt to absorb hydrogen as well. The method consists of making a preliminary milling operation with the elemental powders (50:50 stoichiometric ratio) to form a strong adhered layer of the milled material on the surfaces of the vial and balls. The main milling operation is then performed with a new powder charge (same composition as before), but now adding a process control agent (stearic acid). Various processing times - 2, 6, 10 and 20 h - were used in the milling experiments. Nanocrystalline TiFe was synthesized in this way with low oxygen contamination, full yields for milling times of 6 h or over, requiring no heat treatments for the first hydrogen absorption. Hydrogen storage capacity of 1.0 wt% at room temperature under 20 bar was attained by the sample milled for 6 h. Kinetic data from samples milled for 2 h and 6 h agreed with Jander model for the rate limiting step of the hydriding reaction, which is based on diffusion with constant interface area.

    Palavras-Chave: intermetallic compounds; alloys; mechanical properties; nanocrystals; milling; hydrogen storage; hydrides; activation analysis


  • IPEN-DOC 26665

    SUZUKI, MIRIAM F. ; OLIVEIRA, JOAO E. ; DAMIANI, RENATA; LIMA, ELIANA R. ; AMARAL, KLEICY C. ; SANTOS, ANDERSON M. de S.; MAGALHÃES, GERALDO S.; FAVERANI, LEONARDO P.; PEREIRA, LUIS A.V.D.; SILVA, FABIANA M.; BARTOLINI, PAOLO . Human bone morphogenetic protein‑2 (hBMP‑2) characterization by physical–chemical, immunological and biological assays. AMB Express, v. 10, n. 1, p. 1-10, 2020. DOI: 10.1186/s13568-020-0964-5

    Abstract: Commercially available preparations of methionyl-human BMP-2 and CHO-derived hBMP-2, which belongs to the transforming growth factor β (TGF-β) superfamily, were used for a complete characterization. This protein is an extremely efficient osteoinductor that plays an important role during bone regeneration and embryonic development. Characterization was carried out via SDS-PAGE and Western blotting, followed by reversed-phase HPLC, sizeexclusion HPLC and MALDI-TOF-MS. The classical in vitro bioassay, based on the induction of alkaline phosphatase activity in C2C12 cells, confirmed that hBMP-2 biological activity is mostly related to the dimeric form, being ~ 4-fold higher for the CHO-derived glycosylated form when compared with the E. coli counterpart. The E. coli-derived methBMP- 2 has shown, by MALDI-TOF-MS, a large presence of the bioactive dimer. A more complex molecular mass (MM) distribution was found for the CHO-derived product, whose exact MM has never been reported because of its variable glycosylation. A method based on RP-HPLC was set up, allowing a quantitative and qualitative hBMP-2 determination even directly on ongoing culture media. Considering that hBMP-2 is highly unstable, presenting moreover an extremely high aggregate value, we believe that these data pave the way to a necessary characterization of this important factor when synthesized by DNA recombinant techniques in different types of hosts.

    Palavras-Chave: proteins; skeleton; human populations; bone cells; cho cells; bioassay; escherichia coli; connective tissue cells


  • IPEN-DOC 26664

    CAMPOS, ALEX C.; PAES, SUANE C.; CORREA, BRUNO S.; CABRERA-PASCA, GABRIEL A.; COSTA, MESSIAS S.; COSTA, CLEIDILANE S.; OTUBO, LARISSA ; CARBONARI, A.W. . Growth of long ZnO nanowires with high density on the ZnO surface for gas sensors. ACS Applied Nano Materials, v. 3, n. 1, p. 175-185, 2020. DOI: 10.1021/acsanm.9b01888

    Abstract: Among the various approaches to grow semiconducting oxide nanowires, the thermal oxidation procedure is considered a simple, efficient, and fast method that allows the synthesis of micro and nanostructured arrangements with controlled size and morphology. In the work reported in this paper, long ZnO nanowires were synthesized on the surface of oxidized high-purity Zn foils by heating in air at different rates and temperatures. The size and morphology investigated by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) for a sample heated at 620 °C with heating rate of 20 °C/min reveal the growth of long ZnO nanowires with length of ∼50 μm and average diameter of 74 nm grown along the ⟨112̅0⟩ direction with high population density. Results with different heating rates indicates that this parameter is determinant in tuning the size, morphology, and population density of nanowires. X-ray diffraction (XRD) shows patterns for both ZnO and metallic Zn with preferential orientation, whereas perturbed angular correlation (PAC) measurements using 111In(111Cd) probe nuclei indicate that probe nuclei occupy only Zn sites in the preferential oriented metallic zinc. However, for samples submitted to high-temperature heating (820 and 1000 °C), XRD yields only the ZnO pattern and, amazingly, PAC continues showing probe nuclei only at metallic Zn sites indicating the presence of thin regions of highly oriented Zn trapped between grains of ZnO. Moreover, this strong preference of indium atoms (of parent radioactive 111In) here revealed helps to understand the oxidation mechanism and the growth of the nanowires.

    Palavras-Chave: zinc oxides; nanowires; electric fields; oxidation; temperature gradients; x-ray diffraction; thermal analysis; transmission electron microscopy


  • IPEN-DOC 26441

    CARDOSO JUNIOR, MARCIO; CHEMALE JUNIOR, FARID; OLIVEIRA, CHRISTIE H.E. de; CRUZ, CARLOS E. de S.; ABREU, CARLOS J. de; GENEZINI, FREDERICO A. . Thermal history of potential gas reservoir rocks in the eastern Parnaíba Basin, Brazil. AAPG Bulletin, v. 104, n. 2, p. 305-328, 2020. DOI: 10.1306/05021918117

    Abstract: The Parnaíba Basin is a major intracratonic sedimentary basin in Brazil with unconventional petroleum systems as a potential natural resource formed by the influence of igneous intrusions. To constrain the thermal history of unexplored potential reservoir rocks in the eastern part of the Parnaíba Basin, sedimentary rocks near intrusions were analyzed by petrography and thermochronology (apatite fission-track [AFT] and zircon fission-track [ZFT] dating). Petrography shows grain dissolution and carbonate pore filling generated by thermal destabilization of feldspars. The AFT results indicate partial annealing by the last magmatic event in the basin, and ZFT results show ages of maximum paleotemperature compatible with the Sardinha magmatic event (120–130 Ma). In thermal history models, rocks close to intrusions experienced maximum paleotemperatures above 300°C, which is higher than what is considered favorable for reservoir rocks. Hydrothermal fluids modified the diagenetic evolution of the succession by dissolving and precipitating carbonate cement in pore spaces. In the studied area, at distances greater than 50m(>164 ft) from the intrusion, the rocks were not substantially altered, and in terms of paleotemperature, they can be considered potentially viable reservoirs. The thermal history analysis of potential tight gas sandstone reservoirs affected by intrusive bodies is valuable for characterizing the thermal enhancement or destruction of the reservoir’s qualities.

    Palavras-Chave: sedimentary basins; natural gas; reservoir rock; geologic deposits; petrography; sandstones; brazil; sedimentary rocks; petroleum geology


  • IPEN-DOC 25852

    MESQUITA, C.H. ; VELO, A.F. ; CALVO, W.P. ; CARVALHO, D.V. ; HAMADA, M.M. . Emission and transmission tomography system applied to analyze industrial process inside chemical reactors. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, v. 954, p. 1-3, 2020. DOI: 10.1016/j.nima.2019.01.073

    Abstract: The tomography techniques are widely used in many industries, such as: chemical, food, pharmaceutical and oil sectors. In the industries the tomography is used to diagnose the state of the machines of production and also in the control of quality of the produced objects. A portable tomography system known as instant-non-scanning type, a similar version of the fourth generation CT, was developed in this work. It is capable to obtain measurements in real time conditions without interrupting the operation of the industrial production and it is useful in the quality control of the means of production and the objects produced. This paper describes an innovative hybrid industrial tomographic system, i.e., simultaneous data from the emission of an internal radioactive source introduced inside to the object (67Ga citrate) and tomographic transmission using five sources of 137Cs positioned externally to the object which are distributed at the vertices of a pentagon. The tomographic system described here is useful for studying dynamic chemical phenomena, associated or not with multiphase systems commonly found in chemical reactors and distillation columns.

    Palavras-Chave: cesium 137; diagnostic techniques; tomography; computerized tomography; image processing; nai detectors; citrates; gallium 67; external irradiation; trace amounts


  • IPEN-DOC 25785

    MARIANO, KELLI C.F.; NASCIMENTO, MONICA H.M. do; QUEROBINO, SAMYR M.; CAMPOS, ESTEFANIA V.R.; OLIVEIRA, JHONES L. de; YOKAICHIYA, FABIANO; FRANCO, MARGARETH K.K.D. ; ALBERTO-SILVA, CARLOS; PAULA, ENEIDA de; LOMBELLO, CHRISTIANE B.; LIMA, RENATA de; FRACETO, LEONARDO F.; ARAUJO, DANIELE R. de. Influence of chitosan-tripolyphosphate nanoparticles on thermosensitive polymeric hydrogels: structural organization, drug release mechanisms and cytotoxicity. International Journal of Polymeric Materials and Polymeric Biomaterials, v. 69, n. 9, p. 592-603, 2020. DOI: 10.1080/00914037.2019.1596909

    Abstract: Chitosan-tripolyphosphate (CS-TPP) nanoparticles containing naproxen (NPX) were dispersed in poloxamer (PL) as unique (PL407) or binary (PL407-PL403) systems. Nanoparticles presented diameter of 250nm and zeta potential of 35mV with drug loading and encapsulation efficiency of 98.4 ± 0.3% and 36.9 ± 0.12%, respectively. NPX-CS-TPP shifted the sol-gel transition and micellization temperatures. PL407-PL403 systems presented G0 >G00 compared to PL407. SAXS patterns revealed transitions from lamellar to hexagonal phase organizations with low drug release rates, in the presence of CS-TPP nanoparticles. NPX-CS-TPP-PL407 induced lower cytotoxicity compared to PL407-PL403 in fibroblasts and osteoblasts, making them promising systems for intra-articular delivery.

    Palavras-Chave: polysaccharides; chitin; nanoparticles; antipyretics; drugs; viability; animal cells; sensitivity; temperature dependence; hydrogels


  • IPEN-DOC 26887

    PRADO, E.S.P. ; MIRANDA, F.S.; PETRACONI, G.; POTIENS JUNIOR, A.J. . Use of plasma reactor to viabilise the volumetric reduction of radioactive wastes. Radiation Physics and Chemistry, v. 168, p. 1-4, 2020. DOI: 10.1016/j.radphyschem.2019.108625

    Abstract: Nuclear reactors, hospitals, industries and research institutes generate considerable amounts of radioactive waste every day. To dispose this waste in a safe and costeffective manner, it must be treated by immobilising the radionuclides and, for better stocking capacity, it must be volumetrically reduced as much as possible. To this end, plasma technology, among other promising technologies for radioactive waste treatment, exposes radioactive waste to temperatures above 1400 °C, thereby substantially reducing its volume. In the planning and managing of radioactive waste, the challenges related to plasma technology are presented as a motivation factor for the possible implantation of plasma reactors in nuclear plants and research centres, thereby improving radioactive waste management. In this study, a thermal plasma treatment process was established, and a plasma reactor was used for compactable waste processing. After 30 min of thermal plasma treatment, the volume reduction factor reached 1:99. The results demonstrate the viability of using a thermal plasma process for the volumetric reduction of radioactive waste in a safe and cost-effective manner.

    Palavras-Chave: radioactive materials; radioactive wastes; radioactive waste management; plasma; reactors; radioactive waste storage; reduction; slags; volume; brazilian cnen; plasma technology


  • IPEN-DOC 26886

    GARCIA, VANESSA S.G. ; ROSA, JORGE M.; BORRELY, SUELI I. . Toxicity and color reduction of a textile effluent containing reactive red 239 dye by electron beam irradiation. Radiation Physics and Chemistry, v. 172, p. 1-5, 2020. DOI: 10.1016/j.radphyschem.2020.108765

    Abstract: Textile effluents are a mixture of dyestuff, surfactants, dispersants, acids, alkalis and bleaching agents, among other compounds, and some of these are highly soluble and relatively recalcitrant. Suitable improvement of textile effluents may require combined treatment processes, such as Conventional Treatments and Advanced Oxidative Process (AOPs). Electron beam irradiation (EBI) has been proposed as a possible technology for the treatment of textile effluents. In this context, the aim of the present study was to evaluate the efficiency of an Electron Beam treatment applied to toxicity and color reduction of a textile effluent containing reactive Red 239 dye. Effluent COD and TOC were also evaluated. The assessed effluents were submitted to EBI treatment at doses ranging from 0.5 to 15 kGy. Vibrio fischeri bacteria and Daphnia similis crustaceans were exposed to both irradiated and non-irradiated effluents, the toxicity was evaluated through EC50 (median effective concentration) calculations. EB irradiation successfully reduced effluent toxicity and color. The EC50 for D. similis(48h) were of 6.31% ± 3.19 (non-irradiated) and 27.56% ± 9.31 (10 kGy), and for V. fischeri(15min), of 7.41% ± 1.52 (nonirradiated) and 31.89% ± 10.99 (10 kGy), respectively. Approximately 70% toxicity reduction was obtained for both organisms, while 95% color reduction was obtained by applying 5 kGy.

    Palavras-Chave: toxicity; textiles; effluents; dyes; color; electron beams; textile industry; bacteria; crustaceans; experimental data; environmental impacts; toxic materials; decomposition


  • IPEN-DOC 26885

    KLUMPP, RAFAEL E. ; DONATUS, UYIME ; ARAUJO, JOAO V.S. ; REDÍGOLO, MARCELO M. ; MACHADO, CARULINE de S.C. ; COSTA, ISOLDA . The effect of acid pickling on the corrosion behavior of a cerium conversion-coated AA2198-T851 Al-Cu-Li alloy. Journal of Materials Engineering and Performance, v. 29, n. 1, p. 167-174, 2020. DOI: 10.1007/s11665-019-04551-9

    Abstract: The effect of acid pickling pretreatments prior to cerium conversion coating process on the corrosion behavior of AA2198-T851 alloy substrates was investigated. Three acid pretreatments were employed: nitric acid (HNO3), phosphoric acid (H3PO4) and sulfuric acid (H2SO4). The cerium conversion coating process was performed using a batch solution composed of cerium nitrate and hydrogen peroxide. Microscopic techniques, electrochemical impedance spectroscopy, polarization resistance and open-circuit potential measurements were employed to investigate the effect of each acid pretreatment. The untreated and nitric acid pretreated substrates presented more defective cerium conversion layers than the substrates treated with phosphoric and sulfuric acids. Accordingly, the corrosion resistance of the untreated and nitric acid-treated substrates was very low, while that of the substrates treated with phosphoric acid and sulfuric acids were greatly improved. The sulfuric acid pickling treatment was the best pretreatment before cerium conversion coating among the investigated pretreatments on the AA2198-T851 Al-Cu-Li alloy.

    Palavras-Chave: inorganic acids; pickling; corrosion pickling; cerium; nitric acid; phosphoric acid; sulfuric acid; coatings; conversion; aluminium alloys; lithium alloys; copper alloys; electrochemistry; corrosion resistance


  • IPEN-DOC 26884

    BENTO, RODRIGO T. ; FERRUS FILHO, ANDRE; FUMAGALLI, MARCO A.. Structural design and stress analysis of a high-speed turbogenerator assembly supported by hydrodynamic bearings. International Journal of Manufacturing, Materials, and Mechanical Engineering, v. 10, n. 1, p. 54-67, 2020. DOI: 10.4018/IJMMME.2020010104

    Abstract: Turbine and bushing bearing are the most critical components of high-speed machines. This article describes the design of a high-speed turbine supported by hydrodynamic bearings. The mathematical dimensioning and the FEM analysis are presented to validate the mechanical strength of the turbine and the bushing bearing models. Fatigue life and factor of safety were also determined. The simulations showed that the maximum Von Mises stress values obtained are associated to the centrifugal force generated by the system rotational movement. The results variation was mainly due to the properties of the materials proposed. For the turbine, 7075-T6 aluminum alloy and SAE 4340 steel obtained satisfactory behavior under a constant operating speed of 30,000 RPM. For the hydrodynamic bearing, the TM23 bronze alloy exhibited excellent results, without fracture, and low mechanical deformation. The models exhibited a great potential employment in several applications, such as biogas systems to generate electrical energy, and educational test bench for thermodynamic and tribological simulations.

    Palavras-Chave: steam turbines; velocity; hydrodynamics; bearings; finite element method; design; stress analysis; wind turbines; turbogenerators


  • IPEN-DOC 26883

    FAZOLIN, GABRIELA N. ; VARCA, GUSTAVO H.C. ; FREITAS, LUCAS F. de ; ROKITA, BOZENA; KADLUBOWSKI, SLAWOMIR; LUGAO, ADEMAR B. . Simultaneous intramolecular crosslinking and sterilization of papain nanoparticles by gamma radiation. Radiation Physics and Chemistry, v. 171, p. 1-7, 2020. DOI: 10.1016/j.radphyschem.2020.108697

    Abstract: Papain-based nanoparticles were recently developed using radiation technologies and proven effective to generate nanosized crosslinked papain particles with preserved enzymatic activity. The applications of such nanostructured systems are expected to be similar to native papain with considerable biopharmaceutical advantages and concern drug loading among other biotechnological applications. The nature of such crosslinks and the possibility to provide simultaneous sterilization have been hypothesized but remain not totally clarified. This manuscript advances the discussion on the radiation-induced synthesis of protein nanoparticles by approaching the nature of the crosslinking and the possible contribution of bityrosine linkages and disulfide bridges to the overall nanoparticle assembly as well as the feasibility of the simultaneous sterilization process under the preestablished conditions of processing. Papain nanoparticles were synthesized and characterized according to size, proteolytic activity, bityrosine, cysteine content and molecular weight by SDS-PAGE upon sonication at 40 kHz. Bacterial identification and the sterility tests were performed in accordance with ISO 11737 prior to and after inoculating 106 CFU of Corynebacterium xerosis. Our experiments evidenced the crosslinking of rather intra- than intermolecular nature and a contribution of cysteine bridges and bityrosine linkages to the stabilization and formation of the papain nanoparticle assembly. The technique was effective to promote simultaneous crosslinking and sterilization at the established conditions of processing and may be validated in accordance with the ISO 11137.

    Palavras-Chave: papain; sh-proteinases; nanoparticles; gamma radiation; proteins; cross-linking; sterilization; bacteria; disulfides


  • IPEN-DOC 26881

    VIANA, ITALLO E.L.; LOPES, RAQUEL M.; SILVA, FLAVIA R.O. ; LIMA, NELSON B. ; ARANHA, ANA C.C.; FEITOSA, SABRINA; SCARAMUCCI, TAIS. Novel fluoride and stannous -functionalized β-tricalcium phosphate nanoparticles for the management of dental erosion. Journal of Dentistry, v. 92, p. 1-6, 2020. DOI: 10.1016/j.jdent.2019.103263

    Abstract: Objective: To evaluate the anti-erosive effect of solutions containing β-tricalcium phosphate (β-TCP) nanoparticles functionalized with fluoride or with fluoride plus stannous on enamel and dentin. Methods: β-TCP nanoparticles were synthesized and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Sixty enamel and dentin specimens were randomly allocated into the groups (n=10): Control (water); F (NaF, 225 ppm F−); F+Sn (NaF+SnCl2, 800 ppm Sn2+); F+β-TCP (F+40 ppm β- TCP); F+Sn+β-TCP (F+Sn+40 ppm β-TCP); F+Sn+100β-TCP (F+Sn+100 ppm β-TCP). Specimens underwent erosion-remineralization cycling (5 min immersion into 1 % citric acid solution and 60 min exposure to artificial saliva, 4×/day, 5 days). Immersion in the test solutions was performed for 2 min, 2×/day. Surface loss (SL, in μm) was determined by optical profilometry at the end of cycling. Data were analyzed using one way- ANOVA and Tukey’s tests (α=0.05). Results: XRD confirmed the β-TCP phase. TEM micrographs showed differences between the bare nanoparticle and the β-TCP functionalized with F and Sn. All enamel groups presented lower SL than the control, with F+Sn, F+Sn+β-TCP, and F+Sn+100β-TCP showing the lowest values. For dentin, all the groups had lower SL than the control. F+β-TCP presented the lowest SL, significantly differing from all the other groups. Conclusion: β-TCP nanoparticles functionalized with fluoride showed improved anti-erosive effect compared to the fluoride solution on dentin. There was no significant effect of the β-TCP nanoparticles functionalized with fluoride plus stannous in both substrates. Clinical Relevance: β-TCP nanoparticles are a promising agent to be added to oral health products to improve the protective effect of fluoride against dentin erosion.

    Palavras-Chave: dentistry; caries; pathological changes; fluorides; enamels; tin fluorides; nanoparticles; tcp; erosion control; mineralization


  • IPEN-DOC 26880

    PALACIOS, RAFAEL da S.; ROMERA, KELLY S.; CURADO, LEONE F.A.; BANGA, NELSON M.; ROTHMUND, LUCAS D.; SALLO, FERNANDO da S.; MORAIS, DENES; SANTOS, ANNA C.A.; MORAES, TONNY J.; MORAIS, FERNANDO G. ; LANDULFO, EDUARDO ; FRANCO, MARCO A. de M.; KUHNEN, IGOR A.; MARQUES, JOÃO B.; NOGUEIRA, JOSE de S.; VALLE JUNIOR, LUIZ C.G. do; RODRIGUES, THIAGO R.. Long term analysis of optical and radiative properties of aerosols in the Amazon Basin. Aerosol and Air Quality Research, v. 20, n. 1, p. 139-154, 2020. DOI: 10.4209/aaqr.2019.04.0189

    Abstract: The Amazon region is an excellent laboratory for analysis of natural aerosols in the wet season; however, in the dry season the biomass burning emissions highly influence it, which considerably alters the physical and chemical properties of the atmosphere. We analyzed long-term time series (2000–2017) of optical and radiative properties of aerosols during dry and rain seasons from nine AERONET stations located in the Amazon Basin (Western Brazil). Aerosols have been classified into two groups: organic carbon (OC) and elemental carbon (EC), which allowed quantification of their effects on the radiative forcing for these sites. It was possible to conclude that the optical depth values of aerosols (AOD 500 nm), which remained in a downward inclination beginning in 2010 to 2012, returned to rise since 2013. The analysis showed that the fraction of biogenic particles varied from approximately 38% to 67% at the site of Manaus EMBRAPA. However, for ATTO this fraction remained practically constant throughout the year, around 68% as the fraction of OC-EC went from approximately 16 to 27%. In that way, the study found that in the central Amazon region, in the dry season, the OC fraction generates instantaneous effects of up to –100 W m–2 in the radiative surface forcing (FR-Surface), while in the Cerrado region (Cuiabá) the instantaneous values reached up to –350 W m–2. The impact of the primary biogenic particles on the radiative flux resulted in a mean, approximately –20 W m–2 FR-Surface, representing 45% of the total effect caused by aerosols in the Amazon.

    Palavras-Chave: aerosols; optical depth curve; albedo; backscattering; scattering; aerosol monitoring; air quality; optical properties


  • IPEN-DOC 26879

    SANTOS, NATHALIA V. dos; VIEIRA, CAROLINA L.Z.; SALDIVA, PAULO H.N.; MAZZILLI, BARBARA P. ; SAIKI, MITIKO ; SAUEIA, CATIA H. ; DE ANDRE, CARMEN D.S.; JUSTO, LISIE T.; NISTI, MARCELO B. ; KOUTRAKIS, PETROS. Levels of Polonium-210 in brain and pulmonary tissues: preliminary study in autopsies conducted in the city of São Paulo, Brazil. Scientific Reports, v. 10, n. 1, p. 1-7, 2020. DOI: 10.1038/s41598-019-56973-z

    Abstract: The accumulation of detectable amounts of radon progeny in human tissues may be a risk factor for development and progression of chronic diseases. In this preliminary study, we analyzed the levels of alpha-emitting radon progeny Polonium-210 (210Po) in the olfactory epithelium, olfactory bulb, frontal lobe, and lung tissues in cadavers from the city of Sao Paulo, SP, Brazil. We also assessed the association between 210Po levels and exposure parameters for urban air pollution using linear regression models adjusted for age, sex, smoke, time living in Sao Paulo, daily commuting, socioeconomic index, and anthracosis (traffic-related black carbon accumulation in the pleural region and in lymph). Our findings show that the concentration of 210Po was associated with anthracosis in lungs of nonsmokers (coefficient = 6.0; standard error = 2.9; p = 0.04). Individuals with lower socioeconomic status also had significantly higher 210Po levels in lungs (coefficient = −1.19; standard error = 0.58; p = 0.042). The olfactory bulb had higher 210Po levels than either olfactory epithelium (p = 0.071), frontal lobe (p < 0.001), or lungs (p = 0.037). Our findings of the deposition of 210Po in autopsy tissues suggest that airborne radionuclides may contribute to the development of chronic diseases, including neurodegenerative diseases.

    Palavras-Chave: body composition; autopsy; polonium 210; progeny; radon; animal tissues; lungs; brain; epithelium; tobacco smokes; air pollution; human populations; urban populations; brazil


  • IPEN-DOC 26878

    TESSARO, ANA P.G. ; ARAUJO, LEANDRO G. de ; VICENTE, ROBERTO . Inventorying the radionuclides in spent cartridge filters from the primary circuit of a nuclear research reactor by the dose-to-activity method. Radiation Physics and Chemistry, v. 171, p. 1-6, 2020. DOI: 10.1016/j.radphyschem.2020.108710

    Abstract: The high activity of spent cartridge filters from the cooling water polishing system of a nuclear research reactor precludes, in routine work of a waste characterization program, the usual method of radiochemical analysis of filter samples. For this waste, the dose-to-activity method, using a gamma spectrometer and a dose rate meter, is an alternative for the determination of the activities of the gamma emitters with acceptable accuracy. The ratio of photon peak-areas from different radionuclides, corrected by the detector energy-dependent efficiency, allowed estimating the proportions between the activities of the different radionuclides present. Finally, the simulation of the counting geometry, using the point-kernel method to estimate the air dose rate resulting from an arbitrary concentration of those radionuclides and the comparison of the calculated with the measured air dose rate have yielded the needed estimates of the activity concentrations. The aim of this paper is to report the development of the method applied for the determination of the concentration of the gamma-emitters present in cartridge filters from the IEA-R1 Nuclear Research Reactor.

    Palavras-Chave: radioactive waste management; calculation methods; radioisotopes; gamma spectrometers; filters; iear-1 reactor; inventories; solid wastes; dose rates


  • IPEN-DOC 26877

    SCHELL, J.; DANG, T.T.; CARBONARI, A.W. . Incorporation of Cd-doping in SnO2. Crystals, v. 10, n. 1, p. 1-7, 2020. DOI: 10.3390/cryst10010035

    Abstract: Tuning the electrical properties of materials by controlling their doping content has been utilized for decades in semiconducting oxides. Here, an atomistic view is successfully employed to obtain local information on the charge distribution and point defects in Cd-doped SnO2. We present a study that uses the time-di erential perturbed gamma–gamma angular correlations (TDPAC) method in samples prepared by using a sol–gel approach. The hyperfine field parameters are presented as functions of the annealing temperature in pellet samples to show the evolution of incorporating Cd dopants into the crystal lattice. Additionally, the system was characterized with X-ray fluorescence, electron dispersive spectroscopy, and scanning electron microscopy after the probe nuclei 111In(111Cd) decayed. The TDPAC results reveal that the probe ions were incorporated into two di erent local environments of the SnO2 lattice at temperatures up to 973 K for cation substitutional sites.

    Palavras-Chave: doped materials; tin oxides; stannates; gamma cascades; angular correlation; perturbed angular correlation; sol-gel process; gamma spectrometers; semiconductor materials; oxides


  • IPEN-DOC 26875

    GROSSO, ROBSON L. ; MUCCILLO, ELIANA N.S. ; MUCHE, DERECK N.F.; JAWAHARRAM, GOWTHAM S.; BARR, CHRISTOPHER M.; MONTERROSA, ANTHONY M.; CASTRO, RICARDO H.R.; HATTAR, KHALID; DILLON, SHEN J.. In situ transmission electron microscopy for ultrahigh temperature mechanical testing of ZrO2. Nano Letters, v. 20, n. 2, p. 1041-1046, 2020. DOI: 10.1021/acs.nanolett.9b04205

    Abstract: This work demonstrates a novel approach to ultrahigh-temperature mechanical testing using a combination of in situ nanomechanical testing and localized laser heating. The methodology is applied to characterizing and testing initially nanograined 10 mol % Sc2O3-stabilized ZrO2 up to its melting temperature. The results suggest that the low-temperature strength of nanograined, d < 50 nm, oxides is not influenced by creep. Tensile fracture of ZrO2 bicrystals produce a weak-temperature dependence suggesting that grain boundary energy dominates brittle fracture of grain boundaries even at high homologous temperatures; for example, T = 2050 °C or T ≈ 77% Tmelt. The maximum temperature for mechanical testing in this work is primarily limited by the instability of the sample, due to evaporation or melting, enabling a host of new opportunities for testing materials in the ultrahigh-temperature regime.

    Palavras-Chave: transmission electron microscopy; ultrahigh temperature; materials testing; mechanical properties; crystals; nanostructures; zirconium oxides; grain boundaries


  • IPEN-DOC 26874

    CAMARGO, V.F. de ; FONTES, E.H. ; NANDENHA, J. ; SOUZA, R.F.B. de ; NETO, A.O. . High activity of Pt–Rh supported on C–ITO for ethanol oxidation in alkaline medium. Research on Chemical Intermediates, v. 46, n. 2, p. 1555-1570, 2020. DOI: 10.1007/s11164-019-04050-5

    Abstract: PtRh/C–ITO electrocatalysts were prepared in a single-step method using H2PtCl6 ·6H2O and RhCl3 ·xH2O as metal sources, sodium borohydride as the reducing agent and a physical mixture of 85% Vulcan Carbon XC72 and 15% In2O3 ·SnO2 (indium tin oxide—ITO) as support. PtRh/C–ITO were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry, chronoamperommetry, attenuated total reflectance, Fourier transform infrared spectroscopy and performance test on direct alkaline ethanol fuel cell. X-ray diffraction patterns for all PtRh/C–ITO indicated a shift in Pt (fcc) peaks, showing that Rh was incorporated into Pt lattice. Transmission electron microscopy for PtRh/C–ITO showed nanoparticles homogeneously distributed over the support with particles size between 3.0 and 4.0 nm. The XPS results for Pt70Rh30/C–ITO showed the presence of mixed oxidation states of Sn0 and SnO2 that could favor the oxidation of adsorbed intermediates by bifunctional mechanism. Pt90Rh10/C–ITO was more active in electrochemical studies, which could be associated with the C–C bond break. Experiments in direct alkaline ethanol fuel cells showed that the power density values obtained for Pt70Rh30/C–ITO and Pt90Rh10/C–ITO were higher than Pt/C, indicating the beneficial effect of Rh addition to Pt and the use of C–ITO support.

    Palavras-Chave: sodium compounds; borohydrides; ethanol; oxidation; reduction; indium oxides; tin oxides; fourier transform spectrometers; fourier transformation


  • IPEN-DOC 26873

    SANTOS, DOUGLAS C.; GOES, JOÃO M.R.; SOUZA, VIVIANE C. de; BISPO, DIEGO F.; OTUBO, LARISSA ; ANDRADE, GEORGE R.S.; CAMARGO, ZAINE T.; SANTOS, EULER A. dos. Green synthesis of silver nanostructures with amino acid-modified Pluronic F127 for antibacterial applications. Applied Surface Science, v. 505, p. 1-12, 2020. DOI: 10.1016/j.apsusc.2019.144449

    Abstract: The aim of this work was to evaluate the use of amino acid-functionalized Pluronic F127 derivatives in the synthesis of silver nanostructures (SNS), such as nanoparticles (SNP) and nanoclusters (SNC). Herein, glycine, Lalanine, and DL-alanine were used to functionalize poly(ethylene oxide) (PEO) end groups from the polymer chain via an esterification pathway. The esterified polymers were used for reducing and stabilizing SNS by a hydrothermal or a photo-assisted route (using a UVA light). The functionalized polymers were characterized by FTIR and the obtained SNS were characterized by UV–vis spectroscopy and TEM, which showed that the SNS obtained by the hydrothermal route are predominantly spherical, whereas those obtained by photo-assisted method give rise to rods and prisms. Kinetic studies showed that alanine and glycine form particles with different rates and that the different enantiomers (L and DL) influence the size and shape of SNS. The nanoparticles obtained by the two routes had their antibacterial efficiency tested against S. aureus by the Agar well diffusion method.

    Palavras-Chave: nanoparticles; silver; nanostructures; pluronics; synthesis; antibiotics; amino acids; alanines; reduction; photochemistry


  • IPEN-DOC 26872

    SARAIVA, CRYSTIAN W.C.; CARDOSO, SIMONE C.; GROPPO, DANIELA P. ; SALLES, ANTONIO A.F. de; AVILA, LUIZ F. de; ROSA, LUIZ A.R. da. Gamma Knife radiosurgery for vestibular schwannomas: evaluation of planning using the sphericity degree of the target volume. PLoS ONE, v. 15, n. 1, p. 1-18, 2020. DOI: 10.1371/journal.pone.0225638

    Abstract: Introduction This study explores the possibility of a relationship between the sphericity degree of a target volume with the dose distribution. This relationship is evaluated based on the ratio isodose volume / target volume (IV/TV) and the metrics coverage, i.e., selectivity, gradient index, conformity index and mean dose when planning radiosurgery for vestibular schwannoma. Methods Sphericity degree (φ) was calculated for each target volume (TV) of 64 patients who underwent stereotactic radiosurgery (SRS) for vestibular schwannoma. The calculation of this parameter was developed using the theoretical definition for operational sphericity φ = VP/ VCS. The values found are evaluated considering the following metrics:—Coverage (C), selectivity (S), gradient index (GI), Paddick conformity index (CIPaddick) and dose distribution (IV/TV). The planning was also carried out considering a spherical target volume defined in a spherical phantom. The spherical volume is the same as the target used in the treatment plan. The planning of the spherical target was considered as a reference plan to evaluate the dose distribution inside and outside the volume. Results It was possible to observe that the majority of target volumes has (ϕ) around 0,66–0,77, corresponding to 54,7% of the total. Considering the mean values for metrics, the results are: C = 0,98, S = 0,78, GI = 3,11 and CI = 0,81. The dose distribution was equivalent for treatment plans and reference plans. Quantitative analysis for IV/TV shows that these values are higher than 30% for treatment plans where shot density is large. Conclusion This study demonstrates that de sphericity degree (φ) can be related to the dose distribution (IV/TV). Therefore the sphericity degree is a good parameter to evaluate the dose distribution of a plan for vestibular schwannoma treatment, considering the reference plan as being a spherical target using a leksell gamma knife® perfexion (LGKP). This study shows that the sphericity degree offers important information of the dose distribution outside and inside the target volume. This is not evaluated by the other parameters already implemented as metric to analyzing the GKP plans.

    Palavras-Chave: neoplasms; radiotherapy; surgery; gamma radiation; vestibular apparatus; therapy; radiation doses; isodose curves


  • IPEN-DOC 26871

    TINTI, VICTOR B.; MARANI, DEBORA; FERLAUTO, ANDRE S; FONSECA, FABIO C. ; ESPOSITO, VINCENZO; FLORIO, DANIEL Z. de. Exsolution of nickel nanoparticles from mixed-valence metal oxides: a quantitative evaluation by magnetic measurements. Particle and Particle Systems Characterization, v. 37, n. 2, p. 1900472-1 - 1900472-7, 2020. DOI: 10.1002/ppsc.201900472

    Abstract: A fast and accurate experimental method is demonstrated to assess the fraction of exsolved metallic nanoparticles using magnetic measurements. As a benchmark, nanometric metallic nickel exsolved from (La1−xSrx)(Cr1−yNiy) O3−δ is used for its high relevance as a solid oxide fuel cell component. The method is based on the difference in the magnetic response of the exsolved metallic nickel (ferromagnetic) and Sr-doped lanthanum chromite ceramic matrix (paramagnetic). The exsolved nickel results in coherent nanoparticles pinned on the surface of the Sr-doped lanthanum chromite ceramic matrix, as evidenced by electron microscopy analyses. The results obtained indicate the procedure as a fast and sensitive method to study the exsolution of ferromagnetic nanoparticles.

    Palavras-Chave: nanoparticles; nickel; magnetic fields; magnetometers; valence; evaluation; ferromagnetic materials


  • IPEN-DOC 26870

    CARVALHO, L.R. de ; VIEIRA, D.P. . Evaluation of genotoxic potential of peptides used in nuclear medicine (PSMA -617 and -11, and ubiquicidine 29-41) using a flow-cytometric, semi-automated analysis of micronuclei frequency in cell cultures. Toxicology Reports, v. 7, p. 304-316, 2020. DOI: 10.1016/j.toxrep.2020.02.003

    Abstract: Assays that rely on the assessment of frequency of micronuclei are important standard techniques currently used to quantify potential genotoxic damage after exposure to chemical or physical agents, such as ionizing radiation, or in pre-clinical studies, to assessment of the genotoxic potential of drugs or its components. The experiments are usually performed using conventional microscopy, but currently the protocols are being upgraded to automated approaches based on flow cytometry protocols based on the elimination of the plasma membrane by chemical agents, allowing quantification by flow cytometry. In this work, the genotoxic potential of peptides used as components of radiopharmaceuticals (PSMA-617 and 11 and Ubiquicidine) was evaluated exposing CHO-KI cells to a wide range of concentration (0.1X and 100X the maximum allowed concentration to human adults). Incubation with PSMA-11 or UBI29–41 did not induce genotoxicity. After 24 h of incubation, PSMA-617 induced genotoxicity only in non-practical concentration (100-fold). Results corroborate the safety of the predrugs and the wide detection range of technique.

    Palavras-Chave: radiopharmaceuticals; toxicity; antigens; peptides; antimicrobial agents; cell cultures; cell flow systems; ionizing radiations


  • IPEN-DOC 26869

    DE LEO, THAIS C.; SANTOS, SOFIA N. dos ; ANDRADE, CAMILLO D.C.; RICCI, EDUARDO; TURATO, WALTER M.; LOPES, NORBERTO P.; OLIVEIRA, RALPH S.; BERNARDES, EMERSON S. ; DIAS-BARUFFI, MARCELO. Engineering of galectin-3 for glycan-binding optical imaging. Biochemical and Biophysical Research Communications, v. 521, n. 3, p. 674-680, 2020. DOI: 10.1016/j.bbrc.2019.10.161

    Abstract: Galectin-3 (Gal-3) is a multifunctional glycan-binding protein that participates in many pathophysiological events and has been described as a biomarker and potential therapeutic target for severe disorders, such as cancer. Several probes for Gal-3 or its ligands have been developed, however both the pathophysiological mechanisms and potential biomedical applications of Gal-3 remain not fully assessed. Molecular imaging using bioluminescent probes provides great sensitivity for in vivo and in vitro analysis for both cellular and whole multicellular organism tracking and target detection. Here, we engineered a chimeric molecule consisting of Renilla luciferase fused with mouse Gal-3 (RLuc-mGal-3). RLuc-mGal-3 preparation was highly homogenous, soluble, active, and has molecular mass of 65,870.95 Da. This molecule was able to bind to MKN45 cell surface, property which was inhibited by the reduction of Gal-3 ligands on the cell surface by the overexpression of ST6GalNAc-I. In order to obtain an efficient and stable delivery system, RLuc-mGal-3 was adsorbed to poly-lactic acid nanoparticles, which increased binding to MKN45 cells in vitro. Furthermore, bioluminescence imaging showed that RLuc-mGal-3 was able to indicate the presence of implanted tumor in mice, event drastically inhibited by the presence of lactose. This novel bioluminescent chimeric molecule offers a safe and highly sensitive alternative to fluorescent and radiolabeled probes with potential application in biomedical research for a better understanding of the distribution and fate of Gal-3 and its ligands in vitro and in vivo.

    Palavras-Chave: proteins; carbohydrates; bioluminescence; luciferase; tumor cells; lectins; molecular biology; probes; engineering; corals


  • IPEN-DOC 26868

    CORREA, E.L. ; BOSCH-SANTOS, B. ; SAXENA, R.N. ; CABRERA-PASCA, G.A.; CARBONARI, A.W. . Effects of an external magnetic field on the hyperfine parameters in RE2O3 (RE = Gd, Er) nanoparticles measured by perturbed angular correlation spectroscopy. AIP Advances, v. 10, n. 1, p. 015039-1 - 015039-6, 2020. DOI: 10.1063/1.5130401

    Abstract: In order to understand the interaction mechanisms in RE2O3 (RE=Gd, Er) nanoparticles (NPs), Perturbed Angular Correlation (PAC) spectroscopy, a local technique, plus external magnetic field, was used to elucidate local interactions and possible mapping of the different contribution in these compounds. NPs were synthesized by thermal decomposition and characterized by transmission electron microscopy and X-ray diffraction. PAC measurements were performed using 111In(111Cd) as probe nuclei, with and without the application of an external magnetic field (EMF) of 0.5 T in different temperatures (50 K, 100 K, 200 K, 300 K). Results show that the hyperfine magnetic field is almost zero when the probe is located at the symmetric site, and ∼4 T and ∼5 T for Gd2O3 and Er2O3, respectively, when the probe occupies the asymmetric field.

    Palavras-Chave: perturbed angular correlation; spectroscopy; magnetic fields; rare earths; hyperfine structure; asymmetry coefficients; thermal analysis; transmission electron microscopy; x-ray diffraction


  • IPEN-DOC 26867

    CABRERA-PASCA, G.A.; BOSCH-SANTOS, B. ; BURIMOVA, A. ; CORREA, E.L. ; CARBONARI, A.W. . Effect of the magnetic impurity on the charge diffusion in highly dilute Ce doped LaMnO3. AIP Advances, v. 10, n. 1, p. 015223-1 - 015223-5, 2020. DOI: 10.1063/1.5130429

    Abstract: LaMnO3+δ is a complex oxide, which, depending on the oxygen excess concentration, presents different crystalline structure and interesting magnetic and electric properties such as colossal magnetoresistance, polaron dynamics, multiferroic behavior, and charge-orbital ordering. This complexity requires different characterization techniques to draw a picture as complete as possible allowing a good understanding of these phenomena. Here, we have used the perturbed angular correlation (PAC) technique to measure hyperfine interactions at La and Mn sites of LaMnO3+δ(δ ∼0.15) using 140Ce and 111Cd at La sites as probe nuclei in order to investigate within an atomic scale the magnetic and electric interactions in this compound. The results show that 111Cd nuclei occupy highly symmetric local sites in agreement with a rhombohedral structure. The magnetic hyperfine field (Bhf ) measured with 111Cd at La sites is very small (Bhf = 0.40 T) due to the supertransferred magnetic field from Mn neighbors through oxygen orbitals. On the other hand, 140Ce nuclei at La sites present a saturation field of around 3.7 T much higher than that expected for La sites (due to the weak transfer field by superexchange mechanism). In addition, for temperature range above the magnetic ordering (200-300 K) a dynamic hyperfine interaction was observed characterized by the attenuation parameter λ(T) whose temperature dependence allowed to determine the activation energy (Ea) associated to charge transfer. The polarization of the 4f -electron of Ce impurities affects the local magnetic field at impurity sites as well as the Ea.

    Palavras-Chave: impurities; magnetic flux; doped materials; perturbed angular correlation; trigonal lattices; hyperfine structure; magnetic moments; cerium additions; lanthanum; thin films; manganese oxides; probes


  • IPEN-DOC 26866

    FERREIRA JUNIOR, J.M.; RAJENDRAN, V.; SIMONELLI, G.; SILVA, A.C.M.; SANTOS, L.C.L.; MATTEDI, S.; PONTES, L.A.M.; COSTA, I. ; ROSSI, J.L. ; BAKER, M.A.. Deposition and characterization of a sol-gel Mg-substituted fluorapatite coating with new stoichiometries. Applied Surface Science, v. 505, p. 1-13, 2020. DOI: 10.1016/j.apsusc.2019.144393

    Abstract: The calcium substitution for magnesium on fluorapatite is attractive because this element is a natural substitute in biological apatites. There are several published stoichiometries for calcium substituted by magnesium fluorapatites and most works point out that the formation and fixation of biomimetic Ca-P coatings in Ringer’s solution were strongly related to Mg2+ content and furthermore the Mg replacement improves the bioactivity of apatite. In the present study, fluorapatite (FA) and fluorapatite substituted with 6% and 7% of magnesium were obtained by deposition via sol-gel coating on substrates of AISI 316L stainless steel to investigate the effect of magnesium substitution on fluorapatite with not yet investigated stoichiometry. Characterization of coating thickness, chemical composition and crystalline structure was performed using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The coating adhesion was evaluated using the pull-out test and the corrosion resistance was undertaken using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The electrochemical results showed improvement in the corrosion resistance of magnesium-fluorapatite compared to fluorapatite coated on AISI 316L stainless steel substrates. The improvement corrosion protection and adhesion performance indicate that such magnesium fluorapatites coatings are very interesting candidates as bioactive coatings for implants.

    Palavras-Chave: stoichiometry; apatites; biological materials; implants; magnesium; coatings; hydroxides; sol-gel process; corrosion


  • IPEN-DOC 26865

    BEZAMAT, JULIANA M.; YOKAICHIYA, FABIANO ; FRANCO, MARGARETH K.K.D. ; CASTRO, SIMONE R.; PAULA, ENEIDA de; CABEÇA, LUIS F.. Complexation of the local anesthetic pramoxine with hydroxypropyl-beta-cyclodextrin can improve its bioavailability. Journal of Drug Delivery Science and Technology, v. 55, p. 1-8, 2020. DOI: 10.1016/j.jddst.2019.101475

    Abstract: Local anesthetics are widely used in clinical procedures, to eliminate pain during/after invasive procedures. A wide range of drug delivery systems has been developed to improve the effect of local anesthetics and/or to reduce their toxicity. Pramoxine (PMX) is a topical anesthetic agent with an unusual (morpholine ring) structure and low solubility (ca. 3 mM at pH 7.4). In this work, a novel formulation was devised for PMX in hydroxypropyl- β-cyclodextrin (HP-β-CD). Host-guest inclusion complex was prepared by the co-solubilization method, with complexation kinetics of 10 h, and 1:1 PMX/HP-β-CD stoichiometry. Complexation promoted 14-fold increase in the solubility of PMX. X-ray diffraction measurements revealed loss of the crystalline PMX pattern in the presence of HP-β-CD, an indication of inclusion complexation. Using 1H NMR (DOSY) experiments the association constant of PMX to HP-β-CD (Ka = 923.1 mol/L) was determined, while nuclear Overhauser (ROESY) analysis confirmed the formation of PMX/HP-β-CD inclusion complex, by detection of spatial proximities between hydrogens from PMX aromatic ring and cyclodextrin's cavity. In two in vitro toxicity models (mouse 3T3 fibroblasts in culture and red blood cells hemolysis) pramoxine toxicity was significantly reduced upon complexation into HP-β-CD. These results point out PMX/HP-β-CD as a promising pharmaceutical formulation to improve the bioavailability of pramoxine, allowing its application beyond topical anesthesia.

    Palavras-Chave: anesthesia; oligosaccharides; complexes; anesthetics; clathrates; nuclear magnetic resonance; stoichiometry; antimitotic drugs; hemolysis; chemical composition


  • IPEN-DOC 26864

    PARDO DIAZ, C.A.; SHIMOKAWA, C.A.K.; SAMPAIO, C.S.; FREITAS, A.Z. ; TURBINO, M.L.. Characterization and comparative analysis of voids in class II composite resin restorations by optical coherence tomography. Operative Dentistry, v. 45, n. 1, p. 71-79, 2020. DOI: 10.2341/18-290-L

    Abstract: Purpose: This study aimed to characterize and analyze the number of voids and the percentage of void volume within and between the layers of class II composite restorations made using the bulk fill technique or the incremental technique by optical coherence tomography (OCT). Methods and Materials: Class II cavities (43432 mm) were prepared in 48 human third molars (n=24 restorations per group, two class II cavities per tooth). Teeth were divided into four groups and restored as follows: group 1 (FOB), bulk filled in a single increment using Filtek One Bulk Fill (3M Oral Care); group 2 (FXT), incrementally filled using four oblique layers of Filtek Z350 XT (3M Oral Care); group 3 (FBF+FXT), bulk filled in a single increment using Filtek Bulk Fill Flowable Restorative (3M Oral Care) covered with two oblique layers of Filtek Z350 XT (3M Oral Care), and group 4 (FF+FXT), incrementally filled using Filtek Z350 XT Flow (3M Oral Care) covered with two oblique layers of Filtek Z350 XT (3M Oral Care). After the restorative procedure, specimens were immersed into distilled water and stored in a hot-air oven at 378C. Forty-eight hours later, thermal cycling was conducted (5000 cycles, 58C to 558C). Afterward, OCT was used to detect the existence of voids and to calculate the number of voids and percentage of voids volume within each restoration. Data were submitted to chi-square and Kruskal- Wallis tests (a=0.05). Comparisons were made using the Dunn method. Results: Voids were detected in all groups, ranging from 0.000002 (FBF+FXT and FF+FXT) to 0.32 mm3 (FBF+FXT). FF + FXT presented voids in all of the restorations and had a significantly higher number of voids per restoration when compared to the other groups (p,0.05), but restorations with the presence of voids were significantly higher only when compared to FXT (p,0.05). FBF + FXT presented a significantly higher percentage of voids volume than that of FXT (p,0.05). When comparing restorations made using high-viscosity resin-based composites (FOB and FXT), no significant differences regarding number of voids or percentage of voids volume were detected (p 0.05). Conclusions: The use of flowable resin-based composites can result in an increased number of voids and percentage of voids volume in restorations, and this appears to be more related to voids present inside the syringe of the material than to the use of incremental or bulk fill restorative techniques.

    Palavras-Chave: dentistry; resins; biological recovery; tomography; optical equipment; images; composite materials; voids; layers


  • IPEN-DOC 26863

    BELLONI, MARCIO ; CONTI, THADEU das N. . Analysis of materials for heat transport in tokamaks. World Journal of Nuclear Science and Technology, v. 10, n. 1, p. 39-46, 2020. DOI: 10.4236/wjnst.2020.101005

    Abstract: Every nuclear power reactor, whether of fusion or fission, is essentially a thermal system that generates electricity. In this sense, there are several problems in relation to this heat transport. The model of plasma confinement by magnetic force, in the nuclear fusion (sterellator and tokamak), has only been 20 years and recently some success in the quality of the generated plasma has been achieved. However, due to the large amount of energy coming from the plasma, the choice of the material that will carry the generated energy is quite troublesome, due to the need to handle a very high temperature for the nuclear fission standards. Solutions are explored by the scientific community to transport the energy generated in the case of the primary circuit, after exceeding breakeven temperature and models that are based on the fission reactors of the fourth generation and those currently in operation, to search for solutions regarding the transport of heat generated for the generation of electric energy. Several materials such as pressurized water, sodium, helium and boron have been considered and studied to form the primary heat transfer circuit for the exchanger. A thorough analysis of these materials is necessary. This research looked at some of these materials for heat transport and power generation. Lithium and helium were found to be the probable materials for conveying heat and cooling in the blanket. The results show that research on blanket materials needs more attention. The quality of these materials needs to be improved by material research, with the ODS EUROFER alloy and other research to reduce material erosion by helium nano bubbles. Plasma quality needs to be improved to keep constant and free of impurities when using lithium in liquid form.

    Palavras-Chave: nuclear power; reactors; thermonuclear reactions; tokamak devices; renewable energy sources; iter tokamak; heating; heat transfer


  • IPEN-DOC 26862

    GARCIA, PAULO R.A.F.; PRYMAK, OLEG; GRASMIK, VIKTORIA; PAPPERT, KEVIN; WLYSSES, WAGNER; OTUBO, LARISSA ; EPPLE, MATTHIAS; OLIVEIRA, CRISTIANO L.P.. An in situ SAXS investigation of the formation of silver nanoparticles and bimetallic silver–gold nanoparticles in controlled wet-chemical reduction synthesis. Nanoscale Advances, v. 2, n. 1, p. 225-238, 2020. DOI: 10.1039/c9na00569b

    Abstract: We present a study on the formation of silver (Ag) and bimetallic silver–gold (AgAu) nanoparticlesmonitored by in situ SAXS as well as by ex situ TEM, XRD and UV-vis analysis in a flow reactor at controlled reaction temperature. The formation mechanism of the nanoparticles is derived from the structural parameters obtained from the experimental data. The evolution of the average particle size of pure and alloyed nanoparticles shows that the particle growth occurs initially by a coalescence mechanism. The later growth of pure silver nanoparticles is well described by Ostwald ripening and for the alloyed nanoparticles by a process with a significantly slower growth rate. Additionally, the SAXS data of pure silver nanoparticles revealed two major populations of nanoparticles, the first one with a continuous crystal growth to a saturation plateau, and the second one probably with a continuous emergence of small new crystals. The particle sizes obtained by SAXS agree well with the results from transmission electron microscopy and X-ray diffraction. The present study demonstrates the capability of an in situ investigation of synthesis processes using a laboratory based SAXS instrument. Online monitoring of the synthesis permitted a detailed investigation of the structural evolution of the system.

    Palavras-Chave: nanoparticles; small angle scattering; x-ray diffraction; silver; bimetals; gold; monte carlo method; nanostructures; alloys


  • IPEN-DOC 26661

    CORREIA, M.M.; CHAMMAS, M.C.; ZAVARIZ, J.D.; ARATA, A. ; MARTINS, L.C.; MARUI, S.; PEREIRA, L.A.A.. Evaluation of the effects of chronic occupational exposure to metallic mercury on the thyroid parenchyma and hormonal function. International Archives of Occupational and Environmental Health, v. 93, n. 4, p. 491-502, 2020. DOI: 10.1007/s00420-019-01499-0

    Abstract: Introduction Experiments in animals exposed to mercury (Hg) in different chemical states have shown thyroid parenchymal and hormone alterations. However, these experiments did not allow the establishment of dose–response curves or provide an understanding of whether these Hg effects on the thyroid parenchyma occur in humans. Objective To evaluate the association between chronic occupational exposure to metallic Hg and alterations in thyroid hormones and gland parenchyma 14 years after the last exposure. Methods A cross-sectional study including 55 males exposed in the past to metallic Hg and 55 non-exposed males, paired by age, was conducted in the Hospital das Clínicas (Brazil) from 2016 to 2017. Serum concentrations of total and free triiodothyronine (TT3 and FT3), free thyroxine (FT4), thyrotropin (TSH), reverse T3 (RT3), selenium and antithyroid antibody titers were obtained. The Hg and iodine concentrations were measured in urine. The thyroid parenchyma was evaluated by B-mode ultrasonography with Doppler. The nodules with aspects suspicious for malignancy were submitted to aspiration puncture with a thin needle, and the cytology assessment was classified by the Bethesda system. The t test or Mann–Whitney test, Chi-square test and Spearman correlation were used to compare the exposed and non-exposed groups and examine the relationships between the variables. Univariate and multivariate logistic regression models were used to trace determinants of the risk of thyroid hormone alteration. Statistical significance was defined by p < 0.05. Results The urinary Hg average was significantly higher in the exposed group than in the non-exposed group (p < 0.01). The mean TSH serum concentration in the exposed group was higher, with a statistically significant difference between the groups (p = 0.03). Serum concentrations of TSH exceeded the normality limit (4.20 μIU/ml) in 13 exposed individuals (27.3%) and 4 non-exposed individuals (7.3%), with a statistically significant association between the hormonal increase and exposure to Hg (p = 0.02). In the logistic regression model, exposure to Hg (yes or no) showed an odds ratio = 4.86 associated with an increase of TSH above the normal limit (p = 0.04). The serum concentrations of RT3 showed a statistically borderline difference between the groups (p = 0.06). There was no statistically significant difference between the mean TT3, FT3 and FT4 serum concentrations in the Hg-exposed group compared to the non-exposed group. The proportions of the echogenicity alterations were higher in the exposed group compared to the non-exposed group (27.3% versus 9.1%; p = 0.03). Papillary carcinomas were documented in three exposed individuals and one non-exposed individual. A follicular carcinoma was recorded in one non-exposed individual. Conclusions Due to the higher serum TSH concentration and the prevalence of parenchymal alterations in the Hg-exposed group, even after cessation of exposure, it is recommended that the thyroid status of exposed workers be followed for a long period.

    Palavras-Chave: mercury; thyroid; thyroxine; selenium; chronic exposure; occupational exposure; blood serum


  • IPEN-DOC 26459

    SAUEIA, CATIA H.R. ; NISTI, MARCELO B. ; SILVA, PAULO S.C. da ; OLIVEIRA, JONATHAN P. de ; MAZZILLI, BARBARA P. . Lixiviation of rare earth elements in tropical soils amended with phosphogypsum. International Journal of Environmental Analytical Chemistry, v. 100, n. 6, p. 675-685, 2020. DOI: 10.1080/03067319.2019.1638918

    Abstract: In Brazil, the main producers of phosphate fertilisers are responsible for the production of approximately 12 million tons of phosphogypsum (PG) per year. This phosphogypsum has been used for many years in agriculture as a soil amendment. For its safe long-term application, it is necessary to characterise the impurities present in phosphogypsum and to study the leaching or dissemination of such impurities to waters or other ecosystem compartments. This paper aims to evaluate the availability of Rare Earth Elements (REEs): La, Ce, Nd, Sm, Eu, Tb and Lu. The technique used for the determination of the elements of interest in the soil, soil mixed with PG, PG and leachate was the instrumental neutron activation analysis. For this purpose, an experiment was carried out, in which columns filled with sandy and clay Brazilian typical soils mixed with phosphogypsum were percolated with water, to achieve a mild extraction of these elements. The results showed that the ƩREE in PG was in the order of 7,600 mg kg−1 while in the leachate, the sum was in the order of 100 μg L−1 results obtained for the available fraction obtained was below 1%, giving evidence that although the REEs are present in the PG in higher concentrations, they are not available to the water. It can be concluded that the addition of PG to the soils does not contribute to a significant enhancement of the REEs in water.

    Palavras-Chave: phosphate minerals; gypsum; rare earths; phosphate rocks; fertilizers; superphosphates; leaching; neutron activation analysis; soils; amendments; leachates; brazil


  • IPEN-DOC 25762

    BARTOLOMEI, SUELLEN S. ; SANTANA, JULYANA G. ; DIAZ, FRANCISCO R.V.; KAVAKLI, PINAR A.; GUVEN, OLGUN; MOURA, ESPERIDIANA A.B. . Investigation of the effect of titanium dioxide and clay grafted with glycidyl methacrylate by gamma radiation on the properties of EVA flexible films. Radiation Physics and Chemistry, v. 169, p. 1-9, 2020. DOI: 10.1016/j.radphyschem.2018.08.022

    Abstract: Many studies report that nanocomposites obtained by dispersion of a small amount nanofiller into the polymer have remarkable improvements achieved in the mechanical and physical properties. However, in order to achieve this great improvement in properties, it is necessary that the nanofillers be dispersed homogeneously into the polymeric matrix. Often this dispersion is difficult to achieve due to the high interfacial energy of the nanoparticles present. This study reports the effect of gamma irradiation induced graft of glycidyl methacrylate (GMA) onto the surface of TiO2 and Clay nanofillers to improve their dispersion into the EVA matrix. The physical and mechanical properties of Ethylene-vinyl acetate copolymer (EVA) flexible films with these nanoparticles were studied. EVA nanocomposite with adding of the different amount of TiO2 and modified montmorillonite clay grafted and un-grafted with glycidyl methacrylate (GMA) using gamma irradiation have been prepared by melt extrusion. The nanocomposite flexible films were produced using a flat die extrusion process. The PGMA-grafted nanofillers were characterized by XRD and TEM analysis. The flexible films were characterized by Tensile tests, ATR–FTIR, UV–VIS, XRD, TG, and FE-SEM analysis to understand the nature of the interaction between the nanofillers and EVA matrix. The results showed that the addition of PGMA-grafted TiO2 and Clay nanofillers into EVA matrix improved the bonding between the nanofillers and matrix. It was also found that the PGMA-grafted nanofillers could be well dispersed into an EVA matrix in contrast to that of un-grafted. The tensile strength and modulus of the resulting EVA/TiO2-PGMA enhanced in comparison to that of un-grafted TiO2. The EVA/Clay-PGMA had slightly decreased tensile strength comparable to that of EVA/Clay but had considerably improved elastic modulus. In addition, the flexible films based on TiO2 exhibited high UV–Vis light absorption with energy gap shifted to the visible region. The results demonstrated that TiO2 and Clay nanofillers grafted with GMA by gamma radiation can be used to prepare EVA flexible films with improved bonding between the nanofillers and matrix and, consequently, enhanced properties for food and cosmetic packaging application.

    Palavras-Chave: dispersions; films; gamma radiation; irradiation; methacrylates; nanocomposites; physical properties; polymerization; titanium oxides; x-ray diffraction


  • IPEN-DOC 25091

    FAZOLIN, GABRIELA N. ; VARCA, GUSTAVO H.C. ; KADLUBOWSKI, SLAWOMIR; SOWINSKI, SEBASTIAN; LUGAO, ADEMAR B. . The effects of radiation and experimental conditions over papain nanoparticle formation: towards a new generation synthesis. Radiation Physics and Chemistry, v. 169, p. 1-8, 2020. DOI: 10.1016/j.radphyschem.2018.08.033

    Abstract: Papain is a natural enzyme extracted from the fruit of Carica papaya Linnaeus, successfully applied in the pharmaceutical area as a drug carrier and debridement agent for wounds. In recent studies papain nanoparticles were synthesized and crosslinked with the use of ionizing radiation in the search for biopharmaceutical advantages as well as the development of bioactive nanocarriers. This study addresses the effects of buffer molarity and irradiation conditions on papain nanoparticles formation. Nanoparticles were synthesized on ice bath using ethanol (20%, v/v) as a cosolvent and crosslinked by gamma radiation using a 60Co source. Experimental variables included the synthesis in deionized water and in 1, 10, 25 and 50mM phosphate buffer, under different temperatures of −20 °C, 0 °C and 20 °C before and throughout the irradiation period, and using radiation dose rates of 0.8, 2, 5 and 10 kGy h−1 to reach the dose of 10 kGy. Proteolytic activity was quantified using Nα- benzoyl-DL-arginine-p-nitroanilide hydrochloride. Nanoparticle size and crosslinking by means of bityrosine were evaluated by dynamic light scattering and fluorescence measurements, respectively. Buffer molarity and radiation dose rate were identified to influence bityrosine formation and proteolytic activity without impacting nanoparticle size. Variations in temperature impacted bityrosine formation exclusively. Optimized conditions for papain nanoparticle synthesis were achieved using 50mM phosphate buffer at the dose rate of 5 kGy h−1 and temperature of 0 °C throughout the process.

    Palavras-Chave: cobalt 60; cross-linking; dose rates; gamma radiation; irradiation; nanoparticles; papain; radiation doses; synthesis


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

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

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

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

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


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

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

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

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

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.