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Numerical Study of Spray Dispersion in a Premixing Chamber for Low-NOx Engines

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Journal of Thermal Science 2000年第3期9卷 282-288页

作者： Jorge Barata Andre silva (Universidade da Beira Interior, Aerospace Sciences Department, Rua Marques d’avila e Bolama, 6200 Covilha, Portugal ) Aerospace Sciences Department Universidade da Beira Interior Covilhã Portugal

The present work describes a numerical study of a confined two-phase flow under high-pressure conditions, typical of gas turbine combustors. An Eulerian frame was used for the gas phase together with a Lagrangian approach to describe the dispersed phase. The computational method was extended to high-pressure environments, which are more representative of the practical gas turbine operating conditions. The results are compared with experimental data, and revealed the ability of the model to increase the knowledge of the turbulent dispersion phenomena for this type of practical conditions (high pressure and confined flow).

关键词： two-phase flows sprays high pressure.

Physicochemical and Chromatographic Profiles of Distilled Sugarcane Spirits Produced in Mozambique

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American Journal of Plant Sciences 2018年第4期9卷 617-627页

作者： Manuel Carlos Minez Tábua Maria das Gracas Cardoso Wilder Douglas Santiago Gustavo da silva Goncalves Richard Bispo Barbosa Allan da silva Lunguinho Renan Elan da silva Oliveira Gabriel Biscotto d’avila Maísa Lamounier Magalhaes David Lee Nelson Department of Chemistry Federal University of LavrasLavrasMGBrazil Department of Food Science Federal University of LavrasLavrasMGBrazil Pro-Reitoria de Pesquisa e Pós-Graduacao Federal University of Vales de Jequitinhonha and MucuriDiamantinaMGBrazil

Knowledge of the chemical composition of Mozambican spirits is extremely important because the studies of potentially toxic compounds have been a determinant factor in quality control. The objectives of this work were to analyze and physicochemically characterize distilled sugarcane spirits and other raw materials from Mozambique on the basis of the standards established by the Brazilian Ministry of Agriculture, Livestock and Food Supply (MAPA). The samples came from five provinces of southern and central Mozambique, provided by the owners of the stills in the localities of Manhica, Xinavane, Chókwe, Massinga, Mafambisse, Beira and Chimoio. The four samples from Brazil were randomly collected from different regions of Minas Gerais. The parameters analyzed were ethanol, methanol, higher alcohols, aldehydes, volatile acidity, furfural, esters and copper concentrations. The Mozambican spirits produced from different raw materials, compared to Brazilian spirits, contained very variable concentrations of the components analyzed. Mozambican spirits are of much lower quality than Brazilian beverages and are not suitable for consumption.

关键词： Mozambican Liquor Quality Distilled Alcoholic Beverages

Some Aspects over Thixotropic Fluid Behavior

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Some Aspects over Thixotropic Fluid Behavior

Pyrolysis Oil from the Fruit and Cake of Jatropha curcas Produced Using a Low Temperature Conversion (LTC) Process: Analysis of a Pyrolysis Oil-Diesel Blend

2012 International Conference on Material Sciences and Manufacturing Technology(ICMSMT 2012)

作者： Hilbeth P.Azikri de Deus Guilherme S.Paez Dupim Claudio R.avila da silva Jr. Nucleus of Applied and Theoretical Mechanics-Nu MAT Post-graduate Program of Mechanical and Materials Engineering-PPGEM Federal University of Technology-Parana （UTFPR）

In this work some theoretical aspects of constitutive equations for thixotropic fluids and restrictions on their functional forms are formally discussed. In the current study a formal emphasis has been given to the structural nature of this substances. The behavior of thixotropic fluids is analyzed in terms of simple isothermal laminar shear flow.

关键词： Thixotropic fluids constitutive equation structural nature

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Energy and Power Engineering 2011年第3期3卷 332-338页

作者： Monique Kort-Kamp Figueiredo Gilberto Alves Romeiro Raquel Vieira Santana silva Priscila Alvares Pinto Raimundo Nonato Damasceno Luiz Antonio d`avila Amanda P. Franco Programa de Pós Graduação em Química Instituto de Química Universidade Federal Fluminense

Background: The LTC process is a technique that consists of heating solid residues at a temperature of 380oC - 420oC in an inert atmosphere and their products are evaluated individually: these products include pyrolysis oil, pyrolytic char, gas and water. The objective of this study was to compare the effects of the use of oils obtained by pyrolysis of Jatropha curcas as an additive for diesel in different proportions. Results: A Low Temperature Conversion (LTC) process carried out on samples of Jatropha curcas fruit and generated pyrolysis oil, pyrolyic char, gas and aqueous fractions in relative amounts of 23, 37, 16 and 14% [w/w] respectively for Jatropha curcas fruit and 19, 47, 12 and 22% [w/w] respectively for Jatropha curcas cake. The oil fractions were analyzed by FTIR, 1H NMR, 13C NMR, GCMS and physicochemical analysis. The pyrolysis oil was added to final concentrations of 2, 5, 10 and 20% [w/w] to commercial diesel fuel. The density, viscosity, sulfur content and flash point of the mixtures were determined. Conclusions: The results indicated that the addition of the pyrolysis oil maintained the mixtures within the standards of the diesel directive, National Petroleum Agency (ANP no 15, of 19. 7. 2006), with the exception of the viscosity of the mixtures containing 20% pyrolysis oil.

关键词： Jatropha curcas Low Temperature Conversion Fuel and Pyrolysis Oil

Mean and Interannual Variability of Maize and Soybean in Brazil under Global Warming Conditions

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American Journal of Climate Change 2013年第4期2卷 237-253页

作者： Flávio Justino Evandro Chaves Oliveira Rafael de avila Rodrigues Paulo Henrique Lopes Goncalves Paulo Jorge Oliveira Ponte Souza Frode Stordal José Marengo Thieres G.da silva Rafael Coll Delgado Douglas da silva Lindemann Luiz Claudio Costa Departamento de Engenharia Agrícola Universidade Federal de ViçosaVicosaBrazil Universidade Federal Rural da Amazônia Instituto Sócio-Ambiental e dos Recursos HídricosBelémBrazil Department of Geosciences University of OsloOsloNorway Instituto Nacional de Pesquisas Espaciais Cachoeira PaulistaBrazil Universidade Federal Rural de Pernambuco Unidade Academica de Serra TalhadaSerra TalhadaBrazil Universidade Federal Rural do Rio de Janeiro Instituto de Florestas/Departamento de Ciencias AmbientaisSeropédicaBrazil

Brazil is responsible for 27% of the world production of soybeans and 7% of maize. Mato Grosso and Para states in Brazil are among the largest producer. The viability to the cultivation of maize (Zea mays) and soybeans (Glycine max), for future climate scenarios (2070-2100, GHG) is evaluated based on crop modeling (DSSAT) forced by observational data and regional climate simulations (HadRM3). The results demonstrated that a substantial reduction in the yield in particular for maize may be expected for the end of the 21st century. Distinct results are found for soybeans. By applying the A2 climate changes scenario, soybean yield rises by up top 60% assuming optimum soil treatment and no water stress. However, by analyzing the inter-annual variability of crop yields for both maize and soybean, could be demonstrated larger year-to-year fluctuations under greenhouse warming conditions as compared to current conditions, leading to very low productivity by the end of the 21st century. Therefore, these Brazilian states do not appear to be economically suitable for a future cultivation of maize and soybeans. Improved adaptation measures and soil management may however partially alleviate the negative climate change effect.

关键词： Climate Changes Soybeans Maize

Evaluation of the 5-HTTLPR and 5-HTTVNTR Polymorphisms in the Serotonin Transporter Gene in Women with Postpartum Depression

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Neuroscience & Medicine 2012年第3期3卷 275-280页

作者： Josi Maria Zimmermann-Peruzatto silvana Almeida Aldo Bolten Lucion Jean Pierre Oses Luciana avila Quevedo Karen Amaral Tavares Pinheiro Ricardo Azevedo da silva Ricardo Tavares Pinheiro Marcia Giovenardi Programa de Pos-Graduacao em Ciencias Biologicas FisiologiaUniversidade Federal do Rio Grande do SulPorto AlegreBrazil Programa de Pos-Graduacao em Ciencias da Saude Universidade Federal de Ciencias da Saúde de Porto AlegrePorto AlegreBrazil Programa de Pós-Graduacao em Saúde&Comportamento Centro de Ciencias da Vida e da SaúdeUniversidade Católica de PelotasPelotasBrazil

Objective: The purpose of the present study was to evaluate the association between the 5-HTTLPR and 5-HTTVNTR polymorphisms in the serotonin transporter gene (SLC6A4) in Brazilian women with diagnosed postpartum depression (PPD) and the presence of depressive symptoms. Method: The cohort consisted of 128 white women who were charac-terized based on skin color and morphological characteristics. The Beck Depression Inventory was used to diagnose PPD and to score the depressive symptoms. The 5-HTTLPR and 5-HTTVNTR polymorphisms were analyzed by PCR-based methods. Results: No association was observed between the PPD diagnosis and either the 5-HTTLPR (p = 0.48) or the 5-HTTVNTR (p = 0.77) polymorphism. When the polymorphisms were analyzed together with haplotype data, the analyses demonstrated that women carriers of the L-12/L-12 diplotype have lower Beck Depression Inventory scores than women carrying other diplotypes (p = 0.04). Discussion: Few studies have investigated the association of SLC6A4 polymorphisms with PPD, and the role of 5-HTTLPR and 5-HTTVNTR polymorphisms in PPD susceptibility has not been established to date. Therefore, our findings link the haplotypes of these two variants with depression symptoms, thereby contributing to our understanding of PPD susceptibility.

关键词： Postpartum Depression Serotonin Transporter 5-HTTLPR 5-HTTVNTR Polymorphisms

Rheological and Thermal Behavior of High-Density Polyethylene (HDPE) at Different Temperatures

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Materials Sciences and Applications 2014年第13期5卷 923-931页

作者： Cynthia D’avila Carvalho Erbetta Getúlio F. Manoel Ana Paula Lelis Rodrigues Oliveira Maria Elisa Scarpelli Ribeiro e silva Roberto Fernando Souza Freitas Ricardo Geraldo Sousa Polymer Science and Technology Laboratory Chemical Engineering Department Engineering School Federal University of Minas Gerais Belo Horizonte Brazil

In the present work, rheological properties of HDPE samples were measured at temperatures of 150°C, 190°C and 230°C. It was shown, by oscillatory tests, at low frequencies, that, for temperatures of 150°C and 190°C, there was a predominance of the viscous behavior over the elastic one. At 230°C, there was a predominance of the elastic contribution, and there was an increase of the molar mass compared with the ones obtained from the tests at 150°C and 190°C. The results obtained from the temperature ramp oscillatory test showed that, up to around 248°C, the viscous behavior prevailed, the opposite being observed at higher temperatures. At 230°C the sample showed significantly lower values of strain when compared with the ones observed at 150°C and 190°C. Oxidative induction time (OIT), melting point and degree of crystallinity were determined by differential scanning calorimetry (DSC). The DSC results and the rheological measurements showed a completely different behavior for the HDPE samples at 230°C compared with the 150°C and the 190°C ones, suggesting that HDPE, at the temperature of 230°C, underwent thermo-oxidative degradation with the initial predominance of crosslinking.

关键词： HDPE Rheology Degradation DSC FTIR

Occurrence of Antimicrobials in River Water Samples from Rural Region of the State of Rio de Janeiro, Brazil

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Journal of Environmental Protection 2016年第2期7卷 230-241页

作者： Mychelle Alves Monteiro Bernardete Ferraz Spisso Julia Rodrigues Martins Pastor dos Santos Rafaela Pinto da Costa Rosana Gomes Ferreira Mararlene Ulberg Pereira Talita da silva Miranda Bárbara Rodrigues Geraldino de Andrade Luiz Antonio d’avila Chemistry School/Federal University of Rio de Janeiro (EQ/UFRJ) Rio de Janeiro Brazil National Institute for Quality Control in Health/Oswaldo Cruz Foundation (INCQS/FIOCRUZ) Rio de Janeiro Brazil University Centre of Barra Mansa (UBM) Barra Mansa Brazil National of Institute of Cancer (INCA) Rio de Janeiro Brazil

The occurrence of antimicrobials in the aquatic environment and drinking water has raised the question of their impact on the environment and public health. Animal production is one of the most expressive activities of Brazilian agribusiness. In order to ensure the productivity and competitiveness of the sector, the use of drugs for therapeutic and prophylactic purposes is a common practice. Due to the continuous release of antimicrobials into the environment, the aim of this study was to compare the frequency of detection of tetracyclines and sulfonamides in surface water collected from rural areas in Lidice District of Rio Claro, in the State of Rio de Janeiro, Brazil. An investigative study was conducted with 24 river water samples analyzed by high-performance liquid chromatography coupled to tandem mass spectrometry and the aim of this study was to determine residues of sulfonamides and tetracyclines based on the USEPA method 1694. The results indicated the presence of sulfamethoxazole and oxytetracycline concentrations at the ng·L-1 level. The applied method showed overall good performance with recoveries above 57%, method detection limits ≤ 7.17 ng·L-1, method quantification limits ≤ 23.90 ng·L-1 and good linearity.

关键词： Antimicrobial LC-MS/MS Surface Water Sulfonamides Tetracyclines

Standardization of Sampling for Isolation of Exosome-Like Small-Extracellular Vesicles from Peripheral Blood from Reproductive-Aged Women

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Open Journal of Obstetrics and Gynecology 2018年第11期8卷 1063-1070页

作者： Jéssica Maria Diehl Júlia Abbade Tronco Natália Prearo Moco Graziela Gorete Romagnoli Ana Clara Faquineli Cavalcante Mendes de avila Juliano Coelho da Silveira Márcia Guimaraes da silva Bruna Ribeiro de Andrade Ramos Department of Pathology Botucatu Medical School Sao Paulo State University (UNESP) Botucatu Brasil Três Lagoas Integrated College—FITL/AEMS Três Lagoas Brasil Department of Microbiology and Immunology Biosciences Institute Sao Paulo State University (UNESP) Botucatu Brasil Department of Veterinary Medicine Faculty of Zoology and Food Engineering Sao Paulo University Pirassununga Brasil

Exosome-like small-extracellular vesicles (sEVs) are extracellular vesicles that act in intercellular communication and are involved in several biologic and pathologic processes. While sEVs increase the stability of their cargo molecules, there is still a need for standardization of sampling and isolation of these microvesicles. We aimed to determine the best sampling method for isolation of sEVs from peripheral blood from reproductive-aged women. Material and Methods: We included samples of plasma from our biobank collected in 2014 by venipuncture in heparin tubes and stored at -80°C. We also included blood samples collected in heparin tubes and Ethylenediamine tetraacetic acid (EDTA) tubes and stored at -80°C for one to two weeks prior processing. All blood samples were collected from the same nine reproductive-aged female volunteers. sEVs were isolated from plasma by ultracentrifugation and filtration and indirectly quantified using Pierce BCA Protein Assay kit. Transmission electron microscopy (TEM) and Nano Tracking Analysis (NTA) were performed to confirm the isolation of sEVs. Results and Discussion: TEM and NTA confirmed the isolation of sEVs. Protein concentration of short-time stored heparin samples was not statistically different from long-time stored heparin samples (1847.2 ± 651.4 vs. 2363.2 ± 1025.1, p = 0.14). There was no difference between heparin and EDTA plasma samples recently collected (2363.2 ± 1025.1 vs. 2044.8 ± 653.2, p = 0.44). In conclusion, blood samples may be collected using heparin or EDTA for isolation of sEVs. Long-time stored plasma samples maintain sEVs integrity and may be used, especially in comparative studies.

关键词： Exosome-Like Small-Extracellular Vesicles Plasma Reproductive-Aged Women