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Journal of natural Gas Chemistry 2008年第2期17卷 175-178页

作者： Francisco E.M.Farias Fernando G.Sales fabiano a.n.fernandes Universidade Federal do Ceará Departamento de Engenharia QuímicaCampus do PiciBloco 70960455-760 Fortaleza-CEBrazil

The dependencies of Fischer-Tropsch synthesis liquid hydrocarbon product distribution on operating pressure and temperature have been studied over three potassium-promoted iron catalysts with increasing potassium molar content. The study followed an experimental planning and the results were analyzed based on surface response methodology. The effects of different operating conditions and potassium contents on the liquid product distribution were compared based on number average carbon number and dispersion. Results showed that high pressures （25 to 30 arm） favored the production of waxes that could be converted into liquid fuels through hydrocracking, while greater direct selectivity towards diesel was favored by low pressure （20 arm） using catalysts with low potassium to iron molar ratios. The liquid product distribution produced using an iron catalyst with high potassium content presented higher number-average number of carbons when compared to the distribution obtained using an iron catalyst with low potassium content.

关键词： Fischer-Tropsch synthesis liquid fuels iron-based catalyst potassium

Modeling of Fischer-Tropsch Synthesis in a Slurry Reactor with Water Permeable Membrane

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Journal of natural Gas Chemistry 2007年第2期16卷 107-114页

作者： fabiano A. n. fernandes Universidade Federal do Ceara Departamento de Engenharia QuimicaCampus Universitario do PiciBloco 70960455-760 Fortaleza-CEBrazil

Fischer-Tropsch synthesis is an important chemical process for the production of liquid fuels and olefins. In recent years, the abundant availability of natural gas and the increasing demand of olefins, diesel, and waxes have led to a high interest to further develop this process. A mathematical model of a slurry membrane reactor used for syngas polymerization was developed to simulate and compare the maximum yields and operating conditions in the reactor with that in a conventional slurry reactor. The carbon polymerization was studied from a modeling point of view in a slurry reactor with a water permeable membrane and a conventional slurry reactor. Simulation results show that different parameters affect syngas conversion and carbon product distribution, such as the hydrogen to carbon monoxide ratio, and the membrane parameters such as membrane permeance.

关键词： slurry reactor membrane reactor Fischer-Tropsch modeling

Ruthenium promotion of Co/SBA-15 catalysts for Fischer-Tropsch synthesis in slurry-phase reactors

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Journal of natural Gas Chemistry 2012年第6期21卷 722-728页

作者： Jocielys Jovelino Rodrigues Gina Pecchi fabiano Andrnarciso fernandes Meiry Glucia Freire Rodrigues Federal University of Campina Grande Academic Unit of Chemical Engineering Facultad de Ciencias Químicas Departamento de Físico-QuímicaUniversidad de Concepción Federal University of Ceara Department of Chemical Engineering

The aim of this work was to evaluate the catalytic properties of a Ru promoted Co/SBA-15 catalyst for Fischer-Tropsch synthesis （FTS）. The Ru promoted Co/SBA-15 catalyst was prepared by wet impregnation method and was characterized by X-ray diffraction, X-ray energy dispersion spectrophotometer, n2 adsorption-desorption, temperature-programmed reduction and transmission electron microscopy. The Fischer-Tropsch synthesis using the catalyst was carried out to evaluate the catalyst activity and its effect on FTS product distribution. The synthesis was carried out in a slurry reactor operating at 513 K, 20 atm, CO ： H2 molar ratio of 1 ： 1. X-ray diffraction showed that the calcined cobalt catalyst did not modify the structure of SBA-15, proving that Co was present in the form of Co3O4 in the catalyst. The addition of cobalt in SBA-15 decreased the specific superficial area of the molecular sieve. Fischer-Tropsch synthesis activity and C5＋ hydrocarbon selectivity increased with the addition of Ru. The increases in activity and selectivity were attributed to the increased number of active sites resulting from higher reducibility and the synergetic effect of Ru and Co. Ru/Co/SBA-15 catalysts showed moderate conversion （40%） and high selectivity towards the production of C5＋（80 wt%）.

关键词： SBA-15 cobalt ruthenium heterogeneous catalyst slurry reactor Fischer-Tropsch synthesis

Hydrodynamics of the interceptor on a 2-D flat plate by CFD and experiments

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Journal of Hydrodynamics 2015年第6期27卷 919-933页

作者： MAnSOORI M. fernandes A.C. Department of naval and Ocean Engineering Federal University of Rio de Janeiro

nowadays, the use of interceptor by both partial and total dynamic lift crafts is quite common. In this article, a lot of evidence is given regarding the effectiveness of interceptor. The interceptor, when placed at the stern region, changes the pressure distribution around the craft. Its presence affects drag force, lifting force and the position of pressure＇s center leading to a new trim. This study focuses on hydrodynamic effects of interceptors on a 2-D fiat plate based on both computational fluid dynamic （CFD） and experimental approaches. The Reynolds average navier-Stokes （RAnS） equations are used to model the flow around a fixed flat plate with an interceptor at different heights and attack angles. Based on finite volume method and SIMPLE algorithm which uses static structures, this model can be analyzed and the RAnS results can be compared with the experimental data obtained in the current channel of the laboratory of waves and current of COPPE/UFRJ （LOC in Portuguese acronym）. According to the results, the increase of pressure at the end of the flat plate was proportional to the interceptor height. In addition, the existence of interceptors can significantly increase the lift force coefficient at high angles of attack also proportional to the interceptor height. The presence of interceptor at the end of the fiat plate increased both the lift coefficient and the drag coefficient but hydrodynamic drag did not grow as fast as the lift coefficient did. The lift coefficient increased much more. Furthermore, the results showed that the interceptor effectiveness is proportional to the boundary layer thickness at the end of the fiat plate. As the interceptor was inside the boundary layer alterations of flow speed led to changes in boundary layer thickness, directly affecting interceptor＇s efficiency. Optimum choice of interceptor height had a great effect on its efficiency, and in choosing it the flow speed and length of the boat must be taken into consideration.

关键词： interceptor craft 2-D fiat plate lifting coefficient Reynolds average navier-Stokes (RAnS) pressure distribution,computational fluid dynamic drag

Vitamin D deficiency,functional status,and balance in older adults with osteoarthritis

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World Journal of Clinical Cases 2021年第31期9卷 9491-9499页

作者： Cláudia n Montemor Marcos Tadeu P fernandes Audrey S Marquez Regina Célia Poli-Frederico Rubens Alexandre da Silva Karen B P fernandes Laboratory of Rehabilitation Research Doctoral Program of Rehabilitation SciencesUniversity Pitágoras Unopar(UNOPAR)Londrina 86041-140ParanaBrazil Department of Anesthesiology Irmandade da Santa Casa de LondrinaLondrina 86010-160ParanaBrazil Health Sciences Research Center University Pitágoras Unopar(UNOPAR)Londrina 86041-140ParanaBrazil Doctoral Program of Rehabilitation Sciences University Pitagoras Unopar(UNOPAR)Londrina 86041-140ParanaBrazil Département des Sciences de la Santé Centre intersectoriel en santédurableLaboratoire de recherche BioNRUniversitédu QuébecàChicoutimi(UQAC)SaguenayG7H 2B1QuébecCanada Centre intégréde santéet services sociaux du Saguenay-Lac-Saint-Jean(CIUSSS SLSJ) Hôpital de La Baie-Services gériatriques spécialisésSaguenayQuébecG7H 7K9Canada

BACKGROUnD Low vitamin D levels are associated with a more severe case of knee osteoarthritis(OA).However,there are few published reports concerning an association between vitamin D deficiency and functional status of individuals with OA and no reports about postural balance in this *** To analyze the relationship between vitamin D deficiency and severity,functional status,and balance in elderly patients with *** In this cross-sectional study,105 elderly patients with hip and knee OA were *** severity was assessed by the Kellgren-Lawrence *** functional status was assessed with the Lequesne *** balance was assessed using a force platform,and center-of-pressure parameters(velocity at anteroposterior and mediolateral axis)were used as the balance *** 25(OH)vitamin D levels were measured using a chemiluminescence *** Most of the patients(mean age:70.6±6.5 years)were female(n=78,74.3%).In the group with vitamin D deficiency,43 patients(56.6%)had severe OA,while 33 patients(43.4%)had mild or moderate OA(χ^(2) test,P=0.04).Patients with vitamin D deficiency showed a higher Lequesne index score(Mann-Whitney test,P=0.04),indicating a worse functional impairment when compared to individuals with normal vitamin D ***,patients with vitamin D deficiency had worse postural balance according to the Mann-Whitney test(P=0.03).COnCLUSIOn Vitamin D deficiency is associated with worse severity,functional status,and postural balance in patients with OA.

关键词： Osteoarthritis Elderly Vitamin D Disability Severity Balance

nano-multilayered Zrn‒Ag/Mo‒S‒n film design for stable anti-frictional performance at a wide range of temperatures

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Friction 2024年第12期12卷 2826-2837页

作者： Hongbo JU Jing LUAn Junhua XU Albano CAVALEIRO Manuel EVARISTO Filipe fernandes School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Department of Mechanical Engineering CEMMPREARISEUniversity of CoimbraRua Luís Reis SantosCoimbra 3030-788Portugal TInT-Laboratory for Tribology and Interface nanotechnology Faculty of Mechanical EngineeringUniversity of LjubljanaAškerčeva 6Ljubljana 1000Slovenia CIDEM ISEP-Polytechnic of PortoRua Dr.António Bernardino de AlmeidaPorto 4249-015Portugal

A multilayer film,composed by Zrn‒Ag(20 nm)and Mo‒S‒n(10 nm)layers,combining the intrinsic lubricant characteristics of each layer was deposited using DC magnetron sputtering system,to promote lubrication in a wide-range of *** results showed that the Zrn‒Ag/Mo‒S‒n multilayer film exhibited a sharp interface between the different layers.A face-centered cubic(fcc)dual-phases of Zrn and Ag co-existed in the Zrn‒Ag layers,whilst the Mo‒S‒n layers displayed a mixture of hexagonal close-packed MoS_(2)(hcp-MoS_(2))nano-particles and an amorphous *** multilayer film exhibited excellent room temperature(RT)triblogical behavior,as compared to the individual monolayer film,due to the combination of a relative high hardness with the low friction properties of both *** reorientation of MoS_(2)parallel to the sliding direction also contributed to the enhanced anti-frictional performance at *** 400℃,the reorientation of MoS_(2)as well as the formation of MoO_(3)phase were responsible for the lubrication,whilst the hard t-ZrO_(2)phase promoted abrasion and,consequently,led to increasing wear *** 600℃,the Ag_(2)MoO_(4)double-metal oxide was the responsible for the low friction and wear-resistance;furthermore,the observed transformation from t-ZrO_(2)to m-ZrO_(2),could also have contributed to the better tribological performance.

关键词： DC magnetron sputtering Zrn‒Ag/Mo‒S‒n multilayer film tribological properties tribo-phases

Sources and implications of particulate organic matter from a small tropical river——Zuari River, India

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Acta Oceanologica Sinica 2020年第4期39卷 18-32页

作者： Dearlyn fernandes Ying Wu Prabhaker Vasant Shirodkar Umesh Kumar Pradhan Jing Zhang State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China national Institute of Oceanography(Council of Scientific and Industrial Research) Dona PaulaGoa 403004India national Institute of Oceanography(Council of Scientific and Industrial Research) Regional Centre4 BungalowsAndheri(West)400053MumbaiIndia

Transitional ecosystems,estuaries and the coastal seas,are distinctively affected by natural and anthropogenic *** matter(OM)originating from terrestrial sources is exported by rivers and forms a key component of the global biogeochemical *** previous studies focused on the bulk biochemical and anthropogenic aspects affecting these *** the present study,we examined the sources and fate of OM entrained within suspended particulate matter(SPM)of the Zuari River and its estuary,west coast of *** using amino acid(AA)enantiomers(L-and D-forms)as biomarkers,other bulk biochemical parameters *** organic carbon(POC),δ13C,particulate nitrogen(Pn),δ15n and chlorophyll a were *** no significant temporal variations were observed in the parameters analyzed;nonetheless,salinity,POC,δ13C,Pn,δ15n,glutamic acid,serine,alanine,tyrosine,leucine and D-aspartic acid exhibited significant spatial variability suggesting source *** POC content displayed weak temporal variability with low values observed during the post-monsoon season attributed to inputs from mixed *** samples were less depleted than the riverine samples suggesting contributions from marine plankton in addition to contributions from river plankton and terrestrial C3 plants *** OM was observed during the monsoon and post-monsoon seasons in the estuarine *** degraded OM was noticed during the pre-monsoon *** component analysis was used to ascertain the sources and factors influencing *** five factors were extracted explaining 84.52%of the total *** first component accounted for 27.10%of the variance suggesting the dominance of tidal influence whereas,the second component accounted for heterotrophic bacteria and their remnants associated with the particulate matter,contributing primarily to the AA *** on this study we ascertained the role of the estuarine turbidity max

关键词： Zuari River estuarine turbidity maximum(ETM) suspended particulate matter(SPM) organic matter(OM) amino acids(AA) degradation index(DI)

Acromyrmex ameliae sp. n. （Hymenoptera： Formicidae）： A new social parasite of leaf-cutting ants in Brazil

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Insect Science 2007年第3期14卷 251-257页

作者： DAnIVAL JOSE DE SOUZA ILKA MARIA fernandes SOARES TEREZInHA MARIA CASTRO DELLA LUCIA Institut de Recherche sur la Biologie de 1'Insecte Université Francois Rabelais Tours France Departamento de Biologia Animal Laboratório de Ecologia de Comunidades Departamento de Biologia Geral Universidade Federal de Vicosa MG 36570-000 Brazil

The fungus-growing ants （Tribe Attini） are a new World group of〉 200 species, all obligate symbionts with a fungus they use for food. Four attine taxa are known to be social parasites of other attines. Acromyrmex （ Pseudoatta） argentina argentina and Acromyrmex （Pseudoatta） argentina platensis （parasites of Acromyrmex lundi）, and Acromyrmex sp. （a parasite of Acromyrmex rugosus） produce no worker caste. In contrast, the recently discovered Acromyrmex insinuator （a parasite of Acromyrmex echinatior） does produce workers. Here, we describe a new species, Acromyrmex ameliae, a social parasite of Acromyrmex subterraneus subterraneus and Acromyrmex subterraneus brunneus in Minas Gerais, Brasil. Like A. insinuator, it produces workers and appears to be closely related to its hosts. Similar social parasites may be fairly common in the fungus-growing ants, but overlooked due to the close resemblance between parasite and host workers.

关键词： Acromyrmex leaf-cutting ants social evolution social parasitism

Can rainfall seasonality trigger soil water repellency in a tropical riparian forest?

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Journal of Forestry Research 2023年第3期34卷 773-780页

作者： Gleicon Queiroz de Brito Johnny Rodrigues de Melo Murta Sérgio fernandes Mendonca Filho Luiz Felippe Salemi núcleo de Estudos e Pesquisas Ambientais e Limnológicas(nEPAL) Faculdade UnB de Planaltina(FUP)Universidade de Brasília(UnB)DFVila Nossa Senhora de FátimaÁrea Universitária 1Planaltina 73345-010Brazil

Though riparian areas generally have a shallow water table and higher soil moisture compared to up slope areas,climatic seasonality may trigger water repellency in tropical riparian forests,which,if persistent,could negatively affect essential ecosystem functions related to water resources protection such as reduced overland-flow,sediment transport,and nutrient *** objective of this study was to answer the following:can tropical riparian forests develop water repellency?If so,does water repellency affect infiltration on a seasonal basis?For this,water repellency and infiltration were measured in a grid of 72points during a dry and a wet month of a tropical riparian forest with a shallow water table in a region with highly marked climatic *** repellency and infiltration were significantly different between the wet and dry *** repellency affected negatively infiltration in the dry month,its effect in the wet month was *** a result,a higher infiltration capacity was observed over the wet *** research has claimed that the development and persistence of repellency in soils could promote other hydrological processes such as overland *** findings shown here demonstrate that such phenomenon does not persist longer than the dry season.

关键词： Hydrophobicity Gallery forest Aquifer recharge Climate change Erosion

Hydrocarbons in particulate samples from wildfire events in central Portugal in summer 2010

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Journal of Environmental Sciences 2017年第3期29卷 122-131页

作者： Ana Vicente Ana Calvo Ana P.fernandes Teresa nunes Cristina Monteiro Casimiro Pio Célia Alves Centre for Environmental and Marine Studies (CESAM) Department of EnvironmentUniversity of Aveiro Department of Physics IMARENABUniversity of León

In summer 2010, twenty eight （14 PM=2.5 samples plus 14 samples PM2.5-10） smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse （PM=2.5-10） and fine （PM2.5） smoke samples. The carbonaceous content （elemental and organic carbon） of particulate matter was analysed by a thermal-optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatog- raphy into three different classes of organic compounds （aliphatics, polycyclic aromatic hydrocarbons （PAHs） and carbonyl compounds）. The organic speciation was performed by gas chromatography-mass spectrometry （GC-MS）. Emissions were dominated by the fine particles, which represented around 92% of the PM10. A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon （OC/EC） ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone 6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic com- pounds and secondary processing accounted for 97% of the apportioned PM2.5 levels.

关键词： WildfiresOrganic carbonOrganic compoundsBiomarkersParticulate matterPortugal