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1. Opacities of Singly and Doubly Ionised Neodymium and Uranium for Kilonova Emission Modeling

Author

Flörs, A., Silva, R. F., Deprince, J., Gallego, H. Carvajal, Leck, G., Martínez-Pinedo, G., Sampaio, J. M., Amaro, P., Marques, J. P., Goriely, S., Quinet, P., Palmeri, P., and Godefroid, M.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Even though the electromagnetic counterpart AT2017gfo to the binary neutron star merger GW170817 is powered by the radioactive decay of r-process nuclei, only few tentative identifications of light r-process elements have been made so far. One of the major limitations for the identification of heavy nuclei is incomplete or missing atomic data. While substantial progress has been made on lanthanide atomic data over the last few years, for actinides there has been less emphasis, with the first complete set of opacity data only recently published. We perform atomic structure calculations of neodymium $(Z=60)$ as well as the corresponding actinide uranium $(Z=92)$. Using two different codes (FAC and HFR) for the calculation of the atomic data, we investigate the accuracy of the calculated data (energy levels and electric dipole transitions) and their effect on kilonova opacities. For the FAC calculations, we optimise the local central potential and the number of included configurations and use a dedicated calibration technique to improve the agreement between theoretical and available experimental atomic energy levels (AELs). For ions with vast amounts of experimental data available, the presented opacities agree quite well with previous estimations. On the other hand, the optimisation and calibration method cannot be used for ions with only few available AELs. For these cases, where no experimental nor benchmarked calculations are available, a large spread in the opacities estimated from the atomic data obtained with the various atomic structure codes is observed.We find that the opacity of uranium is almost double the neodymium opacity., Comment: 20 pages, 13 figures. Accepted by MNRAS

Published
2023
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10. ATENDIMENTO PSICOSSOCIAL DE ADOLESCENTES EM CONFLITO COM A LEI: resultados de pesquisas e práticas exitosas

Author

PESSOA, A. S. G., primary, ROSA, E. M., additional, ALBERTO, M. F. P., additional, MUNIZ, A. S., additional, ARAÚJO, Allana de Carvalho, additional, CAVALCANTE, A. L. L., additional, DIAS, A. C. G., additional, SANTOS, A. L., additional, LIMA, A. L. D., additional, SENA, B. C. S., additional, MURGO, Camélia Santina, additional, COSTA, C. S. S., additional, SILVA, E. B. F. L., additional, MARCILIO, F. C. P., additional, CRUZ, F. H. P., additional, MERCÊS, G. C. S., additional, ALMEIDA, H. C. D., additional, PAIVA, I. L., additional, ZAPPE, Jana Gonçalves, additional, GUIMARÃES, L. C., additional, TEIXEIRA, M. A. P., additional, DOMINGOS, M. A. C., additional, FRANCO, M. G. O., additional, SILVA, M. S., additional, MELLO, M. A., additional, BAZON, M. R., additional, MORAIS, N. A., additional, COSTA, R. S., additional, SILVA, R. F., additional, ALMEIDA, S. P. D., additional, KOLLER, S. H., additional, Sousa, T. R., additional, FELICIO, T. L., additional, MALAQUIAS, T. A. P., additional, and Coscioni, V., additional

Published
2020
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11. Domain imaging, MOKE and magnetoresistance studies of CoFeB films for MRAM applications

Author

Teixeira, J. M., Silva, R. F. A., Ventura, J., Pereira, A. M., Carpinteiro, F., Araujo, J. P., Sousa, J. B., Cardoso, S., Ferreira, R., and Freitas, P. P.

Subjects
Condensed Matter - Materials Science
Abstract

We present a detailed study on domain imaging, Kerr effect magnetometry (MOKE) and magnetoresistance (MR), for a series of 20 nm Co$_{73.8}$Fe$_{16.2}$B$_{10}$ thin films, both as-deposited (amorphous) and annealed (crystalline). By considering the two different (orthogonal) in-plane magnetization components, obtained by MOKE measurements, we were able to study the uniaxial anisotropy induced during CoFeB-deposition and to discriminate the magnetization processes under a magnetic field parallel and perpendicular to such axis. MOKE magnetic imaging enabled us to observe the dominant magnetization processes, namely domain wall motion and moment rotation. These processes were correlated with the behavior of the magnetoresistance, which depends both on short-range spin disorder electron scattering and on the angle between the electrical current and the spontaneous magnetization ($\emph{\textbf{M}}_{S}$). A simple numerical treatment based on Stoner-Wolfarth model enables us to satisfactorily predict the magnetization behaviour observed in these films. A comparison between the results in Co$_{73.8}$Fe$_{16.2}$B$_{10}$ films and the previous ones obtained in annealed Co$_{80}$Fe$_{20}$ films, show that the introduction of boron in CoFe reduces significatively the coercive and saturation fields along the easy axis (e.g. $H_{c}$ from $\sim$ 2 down to $\sim$ 0.5 kAm$^{-1}$). Also, the magnetization along the hard axis saturates at lower fields. We conclude that amorphous and nanocrystalline CoFeB films show low coercive fields and abrupt switching, as well as absence of short range spin disorder effects after switching when compared with Co$_{80}$Fe$_{20}$.

Published
2005

12. Short-range effects and magnetization reversal in Co$_{80}$Fe$_{20}$ thin films: a MOKE magnetometry/domain imaging and AMR study

Author

Teixeira, J. M., Silva, R. F. A., Ventura, J., Pereira, A., Araujo, J. P., Amado, M., Carpinteiro, F., Sousa, J. B., Cardoso, S., Ferreira, R., and Freitas, P.

Subjects
Condensed Matter - Materials Science
Abstract

A MOKE magnetometry unit simultaneously sensitive to both in-plane magnetization components, based on an intensity differential detection method, allows us to observe the uniaxial anisotropy impressed during CoFe-deposition and to discriminate the magnetization processes under a magnetic field parallel and perpendicular to such axes. Our MOKE imaging unit, using a CCD camera for Kerr effect domain visualization provides direct evidence on the dominant M-processes, namely domain wall motion and moment rotation. Further magnetic information was obtained by AMR measurements due to the dependence of the electrical resistivity on the short-range spin disorder and also on the angle between the electrical current direction (I) and the spontaneous magnetization ($\emph{\textbf{M}}_{S}$)., Comment: 5 pages, 2 figures

Published
2005

18. Opacities of singly and doubly ionised neodymium and uranium for kilonova emission modeling

Author

Flörs, A, primary, Silva, R F, additional, Deprince, J, additional, Gallego, H Carvajal, additional, Leck, G, additional, Shingles, L J, additional, Martínez-Pinedo, G, additional, Sampaio, J M, additional, Amaro, P, additional, Marques, J P, additional, Goriely, S, additional, Quinet, P, additional, Palmeri, P, additional, and Godefroid, M, additional

Published
2023
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22. Occurrence and diversity of arbuscular mycorrhizal fungi in yerba mate (Ilex paraguariensis - Aquifoliaceae) cultivation environments.

Author

dos Santos, V. J., de Barros, G., Moreira, T. F., de R. Giovenardi, A., Magalhães, J. B., Steffen, G. P. K., Stürmer, S. L., and da Silva, R. F.

Subjects
VESICULAR-arbuscular mycorrhizas, SILVOPASTORAL systems, SOIL microbial ecology, BIOLOGICAL variation, ERROR probability
Abstract

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2024
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23. Arbuscular mycorrhizal fungi on the development and copper content in corn and sorghum plants.

Author

Barros, S., Turchetto, R., Magalhães, J. B., Canepelle, E., Andreola, D. S., Ros, C. O., Basso, C. J., Silva, V. R., and Silva, R. F.

Subjects
VESICULAR-arbuscular mycorrhizas, COPPER, COPPER in soils, CORN, FUNGAL colonies
Abstract

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2024
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24. Nutrient availability and growth of bell pepper plants under fertilization management with humic substances and cattle manure.

Author

Silva, R. F., Silva, I. L. M., Dias, B. O., Pereira, W. E., Campos, M. C. C., Meneses, C. H. S. G., Alves, J. C. G., Ribeiro, J. E. S., and Dias, T. J.

Subjects
HUMUS, CATTLE manure, PLANT fertilization, PLANT nutrition, SOIL fertility, BELL pepper
Abstract

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2024
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27. G

Author

Hashimoto, Yuichi, Haga, Tatsuya, Sonnenfeld, Margaret J., Hlavacka, F., Piggins, Hugh, Silver, Rae, Shinal, René M., Fillingim, Roger B., Blits, Bas, Verhaagen, Joost, Milligan, Erin D., Maier, Steven F., Watkins, Linda R., French, Curtis R., Waskiewicz, Andrew J., McFarlane, Sarah, Rathbun, Daniel L., Usrey, W. Martin, Winklhofer, Michael, Ehrenstein, Walter H., Brites, D., Fernandes, A., Falcão, A. S., Brito, M. A., Silva, R F. M., Fawcett, James W., Ikenaka, Kazuhiro, Mrugala, Maciej M., Johnson, Brett A., Leon, Michael, Matute, Carlos, Bockaert, Joël, Molliver, Derek C., Flynn, Kevin C., Bamburg, James R., Fukumitsu, Hidefumi, Furukawa, Shoei, Young, Deborah, Albers, Kathryn M., Metz, Gerlinde A., Faraji, Jamshid, Oliveira-Maia, Albino J., Simon, Sidney A., Nicolelis, Miguel A. L., Meyerhof, Wolfgang, Binder, Marc D., editor, Hirokawa, Nobutaka, editor, and Windhorst, Uwe, editor

Published
2009
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28. The Genomic Structure of Marek’s Disease Virus

Author

Silva, R. F., Lee, L. F., Kutish, G. F., Compans, R. W., editor, Cooper, M., editor, Ito, Y., editor, Koprowski, H., editor, Melchers, F., editor, Oldstone, M., editor, Olsnes, S., editor, Potter, M., editor, Vogt, P. K., editor, Wagner, H., editor, and Hirai, Kanji, editor

Published
2001
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37. Smoothed Particle Hydrodynamics simulations of reef surf zone processes driven by plunging irregular waves

Author

Lowe, R. J. (author), Altomare, C. (author), Buckley, M. L. (author), da Silva, R. F. (author), Hansen, J. E. (author), Rijnsdorp, D.P. (author), Domínguez, J. M. (author), Crespo, A. J.C. (author), Lowe, R. J. (author), Altomare, C. (author), Buckley, M. L. (author), da Silva, R. F. (author), Hansen, J. E. (author), Rijnsdorp, D.P. (author), Domínguez, J. M. (author), and Crespo, A. J.C. (author)

Abstract

As waves interact with the slopes of coral reefs and other steep bathymetry profiles, plunging breaking usually occurs where the free surface overturns and violent water motion is triggered. Resolving these surf zone processes pose significant challenges for conventional mesh-based hydrodynamic models, due to the rapidly-deforming nature of the free surface and associated flows. Yet the accurate prediction of these surf zone hydrodynamics is critical for predicting a wide range of nearshore processes driven by wave breaking (e.g., wave dissipation and energy transfers; mean water levels and currents; and wave runup). In this study we assess the ability of the mesh-free, Lagrangian particle-based numerical modelling approach Smoothed Particle Hydrodynamics (SPH) based on DualSPHysics, to simulate the fine-scale hydrodynamic processes driven by irregular wave transformation over a fringing reef profile, by comparing results against detailed experimental observations from a physical modelling study. To greatly improve the computational efficiency, the SPH model was coupled to the mesh-based multi-layer nonhydrostatic wave-flow model SWASH. With this coupled approach, SWASH was used to efficiently simulate the evolution of non-breaking waves from the wavemaker up to the fore reef slope, with the SPH model then used to simulate the detailed hydrodynamic processes over the reef from just offshore of the breakpoint to the shoreline. The SPH model was able to accurately reproduce the complex free surface deformations during plunging breaking, the spectral evolution of waves across the reef flat (including nonlinear wave shape), the mean water levels and currents, and wave runup at the shoreline. Using the long duration simulations (>400 wave periods), the model was able to reproduce the full range of wave motions over the reef (from sea-swell to infragravity frequencies), including the increasing dominance of low frequency waves towards the shoreline and the large cro, Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Environmental Fluid Mechanics

Published
2022
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40. Building a community-based FAIR metadata schema for Brazilian agriculture and livestock trading data

Author

SOARES, F. M., CORRÊA, F. E., PIRES, L. F., SANTOS, L. O. B. da S., DRUCKER, D. P., BRAGHETTO, K. L., MOREIRA, D. de A., DELBEM, A. C. B., SILVA, R. F. da, LOPES, C. O. da S., SARAIVA, A. M., FILIPI MIRANDA SOARES, UNIVERSIDADE DE SÃO PAULO, UNIVERSITY OF TWENTE, FERNANDO ELIAS CORRÊA, UNIVERSIDADE DE SÃO PAULO, LUIS FERREIRA PIRES, UNIVERSITY OF TWENTE, LUIZ OLAVO BONINO DA SILVA SANTOS, UNIVERSITY OF TWENTE, LEIDEN UNIVERSITY MEDICAL CENTER, DEBORA PIGNATARI DRUCKER, CNPTIA, UNIVERSIDADE DE SÃO PAULO, KELLY ROSA BRAGHETTO, UNIVERSIDADE DE SÃO PAULO, DILVAN DE ABREU MOREIRA, UNIVERSIDADE DE SÃO PAULO, ALEXANDRE CLÁUDIO BOTAZZO DELBEM, UNIVERSIDADE DE SÃO PAULO, ROBERTO FRAY DA SILVA, UNIVERSIDADE DE SÃO PAULO, CELSO OVIEDO DA SILVA LOPES, UNIVERSIDADE DE SÃO PAULO, and ANTONIO MAURO SARAIVA, UNIVERSIDADE DE SÃO PAULO.

Subjects
Dados de negociação, Metadata, Livestock, Trading data, Agricultura, Agriculture, Metadados, Princípios FAIR, FAIR data principles
Abstract

In this paper, we discuss how we are using metadata schemas and controlled vocabularies to improve interoperability between Brazilian agriculture and livestock trading data providers. A new metadata schema is being created based on a community-based approach. This method relies on knowledge from specialists to define a list of relevant metadata properties for a given domain. In the first step of the research, we extracted metadata from three datasets maintained by three Brazilian public institutions: the Center for Advanced Studies in Applied Economics (Cepea), the Institute of Applied Economic Research (Ipea), and The National Supply Company (Conab). The extracted metadata were the input to the definition of a list of 15 potential metadata properties that specialists are validating. Made available in DSpace on 2022-10-25T15:10:28Z (GMT). No. of bitstreams: 1 AP-Building-Community-Based-FAIR-2022.pdf: 258413 bytes, checksum: 9fd35929d8c05b5bf8ae3becbcc56af7 (MD5) Previous issue date: 2022 Edition of the 18th International Conference on Semantic Systems, Vienna, Austria. SEMANTiCS 2022.

Published
2022

43. Análise dos parâmetros físico-químicos das águas subterrâneas do bairro Enseada das Gaivotas (Rio das Ostras – Rio de Janeiro)

Author

Silva, R. F, Santos, J. V. V, and Pires, C. K

Abstract

R E S U M O A cidade de Rio das Ostras, no Rio de Janeiro, é uma cidade de emancipação relativamente recente e o estudo das condições da qualidade hidrogeológica dos seus bairros é importante neste contexto, pois revela os impactos da urbanização recente no município. O bairro da Enseada das Gaivotas é uma área onde estas análises se fazem especialmente necessárias, já que em seu arredor existe uma unidade de conservação ambiental, e as atividades humanas no local podem influenciar e alterar negativamente o ambiente local, comprometendo os anseios da comunidade, bem como seu bem-estar, segurança, produtividade e lazer. O projeto se desenvolveu na realização de coletas em 20 pontos para suficiente cobertura da área de 1136 km2 que comporta a população de aproximadamente 3000 residentes e subsequente caracterização e análise da água in natura dos poços existentes no local. Nas amostras foram analisados os parâmetros de cloretos (0,1080 e 4,1123 mg L-1), dureza (20,0478 mg L-1 e 223,3196 mg L-1), ferro total (0,001014 mg L-1 e 0,508 mg L-1), e sulfato total (1,35 mg L-1 e 294,46 mg L-1). O estudo possibilitou o conhecimento das características hídricas subterrâneas da região sob os limites utilizados e previstos pelos órgãos e agências reguladoras, conforme o Conselho Nacional do Meio Ambiente (CONAMA) e Ministério da Saúde; caracterizando, em parte, a potabilidade e a qualidade da água utilizada pelos moradores da localidade. Palavras-Chaves: Potabilidade, recursos hídricos, parâmetros físico-químicos.

Published
2021
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44. An��lise dos par��metros f��sico-qu��micos das ��guas subterr��neas do bairro Enseada das Gaivotas (Rio das Ostras ��� Rio de Janeiro)

Author

Silva, R. F, Santos, J. V. V, and Pires, C. K

Abstract

R E S U M O A cidade de Rio das Ostras, no Rio de Janeiro, �� uma cidade de emancipa����o relativamente recente e o estudo das condi����es da qualidade hidrogeol��gica dos seus bairros �� importante neste contexto, pois revela os impactos da urbaniza����o recente no munic��pio. O bairro da Enseada das Gaivotas �� uma ��rea onde estas an��lises se fazem especialmente necess��rias, j�� que em seu arredor existe uma unidade de conserva����o ambiental, e as atividades humanas no local podem influenciar e alterar negativamente o ambiente local, comprometendo os anseios da comunidade, bem como seu bem-estar, seguran��a, produtividade e lazer. O projeto se desenvolveu na realiza����o de coletas em 20 pontos para suficiente cobertura da ��rea de 1136 km2 que comporta a popula����o de aproximadamente 3000 residentes e subsequente caracteriza����o e an��lise da ��gua in natura dos po��os existentes no local. Nas amostras foram analisados os par��metros de cloretos (0,1080 e 4,1123 mg L-1), dureza (20,0478 mg L-1 e 223,3196 mg L-1), ferro total (0,001014 mg L-1 e 0,508 mg L-1), e sulfato total (1,35 mg L-1 e 294,46 mg L-1). O estudo possibilitou o conhecimento das caracter��sticas h��dricas subterr��neas da regi��o sob os limites utilizados e previstos pelos ��rg��os e ag��ncias reguladoras, conforme o Conselho Nacional do Meio Ambiente (CONAMA) e Minist��rio da Sa��de; caracterizando, em parte, a potabilidade e a qualidade da ��gua utilizada pelos moradores da localidade. Palavras-Chaves: Potabilidade, recursos h��dricos, par��metros f��sico-qu��micos.

Published
2021
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45. Si3N4 recubierto con diamante CVD mediante filamento caliente y plasma generado por microondas

Author

Belmonte, M., Costa, F. M., Fernandes, A. J. S., Oliveira, F. J., Tallaire, A., and Silva, R. F.

Subjects
Diamond, silicon nitride, HFCVD, MPCVD, Diamante, nitruro de silicio, Clay industries. Ceramics. Glass, TP785-869
Abstract

Silicon nitride substrates have been diamond coated by hot-filament (home made) and microwave plasma (commercial) CVD reactors. The importance of Si3N4 as substrate relies on its favoured adhesion to the diamond film, as required in wear applications. Diamond coatings have been characterized by μ-Raman spectroscopy, X-ray diffraction, scanning electron microscopy and atomic force microscopy. The diamond film/substrate adhesion has been evaluated by performing Brale indentations at different loads. The diamond films grown by hot filament matched those grown by microwave plasma in terms of morphology and diamond quality, only loosing in uniformity. Spherical substrates have also been used to compare the films coated by both techniques.Se han depositado películas de diamante CVD sobre substratos de nitruro de silicio empleando un reactor experimental de filamento caliente y un reactor comercial que utiliza un plasma generado por microondas. La importancia del Si3N4 como substrato reside en que favorece una buena adhesión con el diamante para ser utilizado en aplicaciones de desgaste. Los recubrimientos obtenidos han sido caracterizados mediante espectroscopía μ-Raman, difracción de Rayos-X, microscopía electrónica de barrido y microscopía de fuerza atómica. El grado de adhesión entre la película y el substrato ha sido determinado realizando una serie de indentaciones con una punta Brale a diferentes cargas. Las películas depositadas mediante filamento caliente son similares, en términos de calidad del diamante y morfología, a las conseguidas con plasma inducido por microondas, aunque presentan problemas de uniformidad. Se han utilizado también substratos con geometría esférica para comparar los recubrimientos obtenidos por ambas técnicas.

Published
2004

46. Sintering of new SiC-Phosphate composite materials for grinding wheels fabrication

Author

Silva, R. F. and Berlinov, H. H.

Subjects
Phosphate bonding, strength, grinding tools, SiC, chemical bonding, Aglomeración química, resistencia mecánica, muelas abrasivas de SiC, Clay industries. Ceramics. Glass, TP785-869
Abstract

The effect of several variables such as molar ratio P2O5/B2O3 (X), temperature and heating cycle on the strength of chemically bonded SiC materials for grinding wheels fabrication was studied. It was shown that the highest compressive strength (52.4 MPa) could be obtained using an optimal molar ratio X = 4.5 and a multiple step heating cycle up to a sintering temperature of 800oC. DTA, XRD, SEM and dilatometrical analysis were performed to follow the different stages of the structural development.Se estudia el efecto de diferentes variables tales como la razón molar P2O5/B2O3(X), temperatura y ciclo de calentamieno sobre la resistencia de materiales de SiC aglomerados quimicamente para la fabricación de muelas arasivas. Se ha comprobado que la más alta resistencia a la compresión (52,4MPa) pueda obtenerse usando una razón molar òptima x= 4,5 y un ciclo de calentamiento en múltiples etapas hasta la temperatura de 800º C. Estudios mediante ATD, DRX, MEB y análisis dilatométricos fueron llevados a cabo para seguir las diferentes etapas del desarrollo microestructura.

Published
2004

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