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Operator Splitting for Three-Phase Flow in Heterogeneous Porous Media

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Communications in Computational Physics 2009年第6期6卷 72-84页

作者： e.Abreu J.Douglas F.furtado F.Pereira Instituto Nacional de Matematica Pura e Aplicada RJ 22460-320Brazil Department of Mathematics Purdue UniversityWest LafayetteIN 47907-1395USA Department of Mathematics University of WyomingLaramieWY 82071-3036USA Department of Mathematics and School of energy Resources University of WyomingLaramieWY 82071-3036USA

We describe an operator splitting technique based on physics rather than on dimension for the numerical solution of a nonlinear system of partial differential equations which models three-phase flow through heterogeneous porous *** model for three-phase flow considered in this work takes into account capillary forces,general relations for the relative permeability functions and variable porosity and permeability *** our numerical procedure a high resolution,nonoscillatory,second order,conservative central difference scheme is used for the approximation of the nonlinear system of hyperbolic conservation laws modeling the convective transport of the fluid *** scheme is combined with locally conservative mixed finite elements for the numerical solution of the parabolic and elliptic problems associated with the diffusive transport of fluid phases and the pressure-velocity *** numerical procedure has been used to investigate the existence and stability of nonclassical shock waves(called transitional or undercompressive shock waves)in two-dimensional heterogeneous flows,thereby extending previous results for one-dimensional flow *** experiments indicate that the operator splitting technique discussed here leads to computational efficiency and accurate numerical results.

关键词： Operator splitting three-phase flow heterogeneous porous media central differencing schemes mixed finite elements

Retreived bacteria from Noctiluca miliaris (green) bloom of the northeastern Arabian Sea

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Chinese Journal of Oceanology and Limnology 2013年第1期31卷 10-20页

作者： BASU Subhajit MATONDKAR SG Prabhu furtado Irene Department of Microbiology Goa University National Institute of Oceanography (CSIR-India)

In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea （NAS）. This study provides the first characterization of bacteria from a seasonal bloom of green Noctiluca ofNAS （20°N-17°N and 64°e-70°e）, during the spring-inter-monsoon cruise ofSagar Sampada 253, in March 2007. Bacterial growth as assessed by most-probable number （MPN） and plate counts, revealed ＇variable-physiotypes＇ over a wide range of salinities （0%-25% w/v NaC1）, pH levels （5-8.5）, and organic nutrient strengths, in comparison to non-bloom waters. MPN indices of bacteria in surface waters of bloom stations ＊DWK and ＊PRB, corresponded to （3.08-4.41）×103 cells/mL at 3.5% NaC1 （w/v）, and （2.82-9.49）× 102 cells/mL at 25% （w/v） NaC1 in tryptone-yeast extract broth （TYe）. Plate counts were （1.12-4） × 106 CFU/mL at 0% （w/v） NaC1, （1.28-3.9） × 106 CFU/mL at 3.5% （w/v） NaC1, and （0.4- 7）×104 CFU/mL at 25% NaC1 （w/v） on TYe. One-tenth-strength Zobell＇s gave （0.6-3.74）× 105 CFU/mL at pH 5 to （3.58-7.5）× 105 CFU/mL at pH 8.5. These bacteria were identified to the genera Bacillus, Cellulomonas, Staphylococcus, Planococcus, Dietzia, Diergibacillus, Micrococcus, Sporosarcinae, Leucobacter, and Halomonas. The identity of three strains （GUFBSS253N2, GUFBSS253N30, and GUFBSS253N84） was confirmed through 16S rDNA sequence homology as Bacillus cohnii, Bacillusflexus, and Bacillus cereus. The -2-3-fold higher plate counts of culturable bacteria from the open-waters of the NAS indicate that these bacteria could critically determine the biogeochemical dynamics of the bloom and its milieu. The role of these bacteria in sustaining/terminating the bloom is under evaluation.

关键词： northeastern Arabian Sea (NAS) green Noctiluca bloom retrievable bacteria

Synthesis of a cardanol-amine derivative using an ionic liquid catalyst

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Frontiers of Chemical Science and engineering 2016年第3期10卷 425-431页

作者： Atanu Biswas Carlucio R. Alves Maria T. S. Trevisan Roseane L. e. da Silva rosel.yne e furtado Zengshe Liu H. N. Cheng USDA Agricultural Research Service National Center for Agricultural Utilization Research Peoria IL 61604 USA Chemistry Department State University of Ceara Itaperi Campus 60740-020 Fortaleza-CE Brazil Chemistry Department Federal University of Ceara Pici Campus 60455-760 Fortaleza-CE Brazil embrapa Tropical Agroindustry Rua Dra. Sam Mesquita Planalto Pici 60511-110 Fortaleza-CE Brazil USDA Agricultural Research Service Southern Regional Research Center New Orleans LA 70124 USA

Cardanol is a biobased raw material derived from cashew nut shell liquid. In order to extend its utility, new derivatives and additional applications are useful. In this work cardanol was first epoxidized, and a novel aniline derivative prepared from it under mild reaction conditions with the help of an ionic liquid catalyst. The reaction chemistry was studied by using nuclear magnetic reso- nance. The resulting aminohydrin adduct showed antiox- idant property and should also be a useful synthon for further reactions. As an example, the aminohydrin was shown to undergo a condensation reaction with formalde- hyde to form a prepolymer, which could be further reacted to form thermosetting resins.

关键词： cardanol epoxidation aminohydrin aniline,ionic liquid aniline-formaldehyde

Obtaining morphometric variables from gullies using two methods of interpolation laser scanner data:the case study of Vassouras,Brazil

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Journal of Mountain Science 2020年第12期17卷 3012-3023页

作者： OLIVeIRA Carlos Magno Moreira de FRANCeLINO Márcio Rocha MeNDONCA Bruno Araujo furtado de RAMOS Isabela Queiroz Instituto Federal do Norte de Minas Gerais-Campus Arinos Rodovia MG 202Km 407 s/nZona RuralArinos-MG38680-000Brazil Departamento de Solos Universidade Federal de VigosaAv.Peter Henry Rolfss/n-Campus UniversitarioViqosa-MG36570-900Brazil Departamento de Silvicultura Universidade Federal Rural do Rio de JaneiroBR 465 Km 07Seropedica-RJ23890-000Brazil Instituto do Meio Ambiente e dos Recursos Hidricos do Distrito Federal SEPN 511Bloco C70750-543BrasiliaDFBrazil

Gully erosion is a worldwide problem of land degradation and water quality,and it is also frequent in ***,anthropic influence is the major driver of gully *** study and monitor gullies it is necessary to use specific instruments and methods to obtain accurate *** objective of this study was to use Terrestrial Laser Scanning(TLS) to create digital elevation model(DeM) accurately and define morphometric variables that characterize gullies in a mountainous *** different interpolations were evaluated using the Topogrid and GridSurfaceCreate algorithms to elaborate *** profile for gullies was used to assess modeling *** DeM of the Gully 1(G1) from the Topogrid algorithm estimated soil loss of 49%,whereas the GridSurfaceCreate algorithm estimated a soil loss of97%,in a period of 1 *** estimated soil loss for the Gully 2(G2) was 14% from the Topogrid,and 8%from the GridSurfaceCreate *** GridSurfaceCreate algorithm underestimated the volume to area ratio for G2 due to a failure on interpolating a region of low point *** Topogrid algorithm represented better the terrain irregularities,as observed through the topographic profiles traced in three regions of G1 and *** analysis showed that the GridSurfaceCreate algorithm presented lower accuracy in estimating *** underestimation trend of this algorithm was also observed in *** gullies showed considerable soil losses,which may reduce the areas suitable for agricultural activities,and silting up of water *** Topogrid algorithm presented satisfactory results,denoting great potential to produce morphometric data of gullies.

关键词： erosion process Interpolation algorithms Spatial statistics Digital elevation Model Topographic profile

Variation of Dust in Northern China and Its Reproduction in BCC-eSM1 since 1980

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Journal of Meteorological Research 2023年第5期37卷 617-631页

作者： Yumeng ZHOU Tongwen WU Jie ZHANG Yong ZHANG Yanwu ZHANG He ZHAO Weihua JIe Yang ZHOU Kalli furtado Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China earth System Modeling and Prediction Centre China Meteorological AdministrationBeijing 100081China Sichuan Climate Center/Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province Chengdu 610072China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081China Meteorological Observation Centre China Meteorological AdministrationBeijing 100081China Nanjing University of Information Science&Technology Nanjing 210044China Met Office Hadley Centre Exeter EX13PBUnited Kingdom

In this paper,we explore the possible causes and mechanisms for the variation of dust in northern China from 1980to 2014 using the Modern-era Retrospective analysis for Research and Applications version 2(MeRRA-2)data,observational data,and BCC-eSM1(Beijing Climate Center earth System Model version 1)simulation *** important dust centers are identified in China:one in the Taklamakan Desert in southern Xinjiang Region and the other in the Badain Jaran Desert in western Inner Mongolia *** centers display distinct seasonal variations,with high dust concentration in spring and summer and low in autumn and ***-eSM1 is able to generally capture the main spatial and temporal characteristics of dust in northern *** the MeRRA-2 reanalysis data and BCCeSM1 simulation data show a decreasing trend in spring dust,which is evident during 1980–2000 and 2001–*** analysis based on daily mean dust loads and wind fields from MeRRA-2 and BCC-eSM1 indicates that dusty weather in North China may be mainly caused by transport of the dust,especially that from the central and western Inner Mongolia Plateau during the prior 0–2 days,through the westerly winds from the upstream“dust core”region(38°–45°N,90°–105°e).This is one of the important paths for dust to move into North *** weakened westerly wind in the lower troposphere in this“dust core”region may be responsible for the reduction of spring dust in North China.

关键词： dust aerosols Coupled Model Intercomparison Project Phase 6(CMIP6) earth system models

experimental investigation on variability in properties of Amazonian wood species Muiracatiara ( Astronium lecointei ) and Maçaranduba ( Manilkara huberi ) focusing guitar fingerboards manufacturing

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Journal of Bioresources and Bioproducts 2021年第1期6卷 33-38页

作者： roseli Felix da Silva Ribeiro JoséFlávio Silveira Feiteira Jayme Pereira de Gouvê Alexandre furtado Ferreira Federal Fluminense University PPGEMVolta RedondaRJBrazil Federal Fluminense University PGMECVolta RedondaRJBrazil

In face of scarcity in the supply of non-traditional Brazilian woods properly treated for use in high quality musical instruments,pieces of Amazonian wood species muiracatiara(Astronium lecointei)and maçaranduba(Manilkara huberi)purchased in the common internal Brazilian timber market were *** species were pre-selected for use in fingerboards of acoustic and electric guitars due to similar properties with ebony(Diospyros crassiflora).Variabilities of elastic modulus parallel to grain and density were investigated inside wooden *** addition,referred parameters were used in calculation of speed of *** tests were performed in order to compare both species and revealed inequality for variances of dynamic elastic modulus(e_(d))and speed of sound,but equality for *** of means was also examined via unequal variance *** color differences,lower variability of *** led to the indication of this species as likely capable to substitute satisfactorily ebony in fingerboards manufacturing.

关键词： Mechanical properties variability Wood grain slope experimental analysis Impulse excitation technique F-test

Mechanisms associated with winter intraseasonal extreme sea ice extent in the Weddell Sea

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Advances in Polar Science 2017年第3期28卷 171-184页

作者： Fabio Ullmann furtado de LIMA Leila M.V.CARVALHO Centro de ensino Superior da Foz do Itajaí-Univ. do estado de Santa Catarina (UDeSC) Dept.of Geography and earth Research Institute University of California Santa Barbara

Previous studies have shown evidence of atmospheric extratropical wave trains modulating sea ice area in the Weddell and Amundsen/Bellingshausen seas on intraseasonal time-scales(20–100 d). Here we investigate mechanisms relating intraseasonal extreme sea ice extent and ekman layer dynamics with emphasis on the Weddell Sea. This study extends from 1989 to 2013 and focuses on the winter season. Wind stress τ is calculated with winds from the Climate Forecast System reanalysis(CFSR) to evaluate momentum transfer between the atmosphere and the ekman layer. Lag-composites of the anomalies of ekman transport and the ekman pumping indicate that divergence of mass in the ekman layer and upwelling lead the occurrence of extreme sea ice contraction on intraseasonal time-scales in the Weddell Sea. Opposite conditions(i.e., convergence of the mass and downwelling) lead extreme sea ice expansion on intraseasonal time-scales. This study suggests that the ekman pumping resulting from the anomalous wind stress on intraseasonal time-scales can transport these warmer waters to the surface contributing to sea ice melting. Additionally, high resolution sea ice fraction and ocean currents obtained from satellite and in situ data are used to investigate in detail mechanisms associated with persistent extreme sea ice expansion and contraction on intraseasonal time-scales. These case studies reveal that atmospheric circumpolar waves on intraseasonal time-scales can induce contrasting anomalies of about ±20% in sea ice concentration at the Weddell and western Antarctica Peninsula margins within less than 30 d. This study shows that extreme anomalies in sea ice may lag between 5–25 d(1–5 pentads) the ocean-atmospheric forcing on intraseasonal time-scales.

关键词： sea ice extent intraseasonal time-scales ekman layer dynamics

Spatial Statistics and Age Structure of Leaf Cutting Ant Nests

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Open Journal of Statistics 2019年第2期9卷 196-217页

作者： Debora Maria Ferreira Canuto Sergio furtado dos Reis Wesley Augusto Conde Godoy Departamento de entomologia e Acarologia Escola Superior de Agricultura Luiz de Queiroz Universidade de Sao Paulo Piracicaba Brazil Departamento de Biologia Animal Universidade Estadual de Campinas Campinas Brazil

In this study, we investigated the spatial aggregation of old and incipient nests of Atta sexdens rubropilosa by fitting Poisson and Negative binomial models to nest abundance data. Our aim is to analyse the distribution of ant nests in eucalypt regrowth, Cerrado and native forest fragment. We also investigated the correlation between nest abundance and climatic factors, as well as different nest ages. When comparing nests of different ages we observed an aggregated pattern for both old and incipient nests. On the other hand, analysing the distribution of nests separately, only taking into account the different areas and respective borders, old nests exhibited an aggregated pattern and incipient nests showed a random pattern, except for native forest with ants exhibiting only an aggregated pattern. The levels of aggregation changed in response to different areas and border gradients, with more external borders showing higher aggregation than more internal borders. Temperature was the variable showing the highest correlation with nest abundance and the correlation between nests of different ages was totally depending on the different areas.

关键词： Spatial Statistics Leaf Cutting Ant Nest Aggregation Nest Age Forest Landscapes

Trichomonas vaginalis perturbs the junctional complex in epithelial cells

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Cell Research 2005年第9期 29-41页

作者： Rodrigo furtado MADeIRO da COSTA,Wanderley de SOUZA,Marlene BeNCHIMOL,John F ALDeReTe,José Andrés MORGADO-DíAZ Programa de Pós Graduao em Ciências Morfológicas Universidade Federal do Rio de Janeiro Rio de Janeiro RJ 20231- 050 Brazil Grupo de Biologia estrutural Diviso de Biologia Celular Centro de Pesquisa Instituto Nacional de Cancer Rio de Janeiro RJ 20231-050 Brazil Grupo de Biologia estrutural Diviso de Biologia Celular Centro de Pesquisa Instituto Nacional de Cancer Rio de Janeiro RJ 20231-050 Brazil Laboratório de Ultraestrutura Celular Hertha Meyer Instituto de Biofísica Carlos Chagas Filho Universidade Federal do Rio de Janeiro Centro de Ciências da Saúde Rio de Janeiro RJ 21944-900 Brazil Laboratório de Ultraestrutura Celular Universidade Santa úrsula Rio de Janeiro RJ 22231-010 Brazil Department of Microbiology University of Texas Health Science Center San Antonio TX 78229-3900 USA Grupo de Biologia estrutural Diviso de Biologia Celular Centro de Pesquisa Instituto Nacional de Cancer Rio de Janeiro RJ 20231-050 Brazil

Trichomonas vaginalis, a protist parasite of the urogenital tract in humans, is the causative agent of trichomonosis, which in recent years have been associated with the cervical cancer development. In the present study we analyzed the modifications at the junctional complex level of Caco-2 cells after interaction with two isolates of T. vaginalis and the influence of the iron concentration present in the parasite’s culture medium on the interaction effects. Our results show that T. vaginalis adheres to the epithelial cell causing alterations in the junctional complex, such as: (a) a decrease in transepithelial electrical resistance; (b) alteration in the pattern of junctional complex proteins distribution as observed for e-cadherin, occludin and ZO-1; and (c) enlargement of the spaces between epithelial cells. These effects were dependent on (a) the degree of the parasite virulence isolate, (b) the iron concentration in the culture medium, and (c) the expression of adhesin proteins on the parasite surface.

关键词： Trichomonas vaginalis Caco-2 junctional complex proteins transepithelial electrical resistance adhesins.