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Flow regimes in wet conical spouted beds using glass bead mixtures

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Particuology 2008年第2期6卷 72-80页

作者： Marcelo s.Bacelos Jos Teixeira freire Universidade Federal de sāo Carlos Centro de Ciências Exatas e de TecnologiaPrograma de Pós-Graduacāo em Engenharia QuímicaCentro de Secagem de PastasSuspensōes e SementesRod.Washington LuizKm 23513565-905CP 676Sāo CarlosSPBrazil

Using a high-viscosity Newtonian fluid, glycerol, an experimental investigation was carried out to evaluate the stable spouting regime in conical spouted beds using four particle mixtures： a reference （monoparticles）, a binary mixture, two ternary mixtures with flat and Gaussian distributions respectively. The mixtures were selected for particle diameters （dp） ranging from 1.09 to 4.98 mm and particle diameter ratios （dpL/dps） ranging from 1.98 to 4.0. Experimental data show that pressure fluctuation signals of the bed, as indicated by changes in their standard deviations, provide suitable information to identify the range of operational conditions for stable spouting. However, the analysis of skewness of curves of pressure fluctuation as a function of air velocity appears not sufficient to identify a particular flow regime. For glycerol in the spouting regime, the standard deviation is noted to increase with increasing glycerol concentration due to the growth of interparticle forces. The implications of these research findings on the drying of suspensions in conical spouted beds using glass bead mixtures are also discussed.

关键词： Conical spouted bed Binary and ternary mixtures Processing of pastes spouting regimes spouting stability Pressure fluctuation

Effect of outplanting time on commercial cultivation of kelp Laminaria saccharina at the southern limit in the Atlantic coast,***

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Chinese Journal of Oceanology and Limnology 2009年第1期27卷 54-60页

作者： César PETEIRO óscar freire Instituto Espaíol de Oceanografía (IEO) Centro Oceanográfico de Santander Promontorio de San Martin s/n. Apdo. 240 39080 Santander Spain Universidad de A Corua (UDC) Facultad de Ciencias 15071 A Corua Spain

The aim of the study is to examine the influence of the outplanting time on the cultivation of the kelp Laminaria saccharina in the northwestern spain, close to its southern limit of distribution in the North Atlantic coast. We compared two L. saccharina cultures outplanted in February and December. We found that the starting time of outplanting affects to the yield and the substantiality value, as well as the growth rate. The yield, the substantiality value and the growth rates of L. saccharina sporophytes obtained for the trial outplanted in December were significantly higher than those in February. These results can be mainly explained by the effect of temperature on the growth of L. saccharina sporophytes during cultivation. On the other hand, our results show that even in the southern limit of distribution of L. saccharina, the cultivation of this species was very profitable in high yield and quality.

关键词： outplanting kelp farming Laminaria substantiality value yield

Drying of pasty and granular materials in mechanically and conventional spouted beds

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Particuology 2019年第1期17卷 176-183页

作者： Robson C. sousa Maria C. Ferreira Haritz Altzibar Fábio B. freire José T. freire Rural and Chemical Engineering Department Federal University of Espirito SantoAlegreES. Brazil Chemical Engineering Department Federal University of Sao CarlosSao CarlosSPBrazil Chemical Engineering Department University of Basque CountryBilbaoSpain

A contactor vessel was built to operate as either a mechanically or a conventional spouted bed for the purpose of analyzing the drying of pasty and granular materials under comparable conditions in both configurations. A classical conical–cylindrical spouted bed with a 60° conical base and an air inlet central orifice was modified to enable the switch by introducing in the vessel’s center an open helicoidal conveyor screw placed above the air inlet orifice. This screw is removable and conveniently returns the bed to its conventional spouted configuration. Experiments on drying solutions (calcium carbonate suspensions and skimmed milk) and granular materials (porous alumina particles) were performed for various bed parameter settings. The spouting pressure drop, outlet air temperature, and relative humidity were measured over time under different conditions. Mechanical agitation is proved effective in drying diluted carbonate calcium liquid suspensions and coarse porous alumina particles at an air velocity approximately 50% lower in comparison to drying in a conventional spouted bed. The conventional spouted bed performed better at drying liquid skimmed milk as the mechanical agitation combined with the axial inlet air flow is not effective in mitigating sticking and powder agglomeration in the bed when handling pastes of complex composition. Introducing mechanical agitation in the designed setup broadens the operating range of a conventional spouted bed with axial air flow in the inlet.

关键词： Characteristic curve Drying kinetic spouted-bed dynamics Mechanical agitation Alumina particles Paste drying

Increasing the detail of European land use/cover data by combining heterogeneous data sets

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International Journal of Digital Earth 2020年第5期13卷 602-626页

作者： Konštantín Rosina Filipe Batista e silva Pilar Vizcaino Mario Marín Herrera sérgio freire Marcello schiavina European Commission Joint Research Centre(JRC)IspraItaly

Data on land use and land cover(LULC)are a vital input for policy-relevant research,such as modelling of the human population,socioeconomic activities,transportation,environment,and their *** Europe,CORINE Land Cover has been the only data set covering the entire continent consistently,but with rather limited spatial *** data sets have provided much better detail,but either have covered only a fraction of Europe(*** Atlas)or have been thematically restricted(*** High Resolution Layers).In this study,we processed and combined diverse LULC data to create a harmonised,ready-to-use map covering 41 *** doing so,we increased the spatial detail(from 25 to one hectare)and the thematic detail(by seven additional LULC classes)compared to the CORINE Land ***,we decomposed the class‘Industrial and commercial units’into‘Production facilities’,‘Commercial/service facilities’and‘Public facilities’using machine learning to exploit a large database of points of *** overall accuracy of this thematic breakdown was 74%,despite the confusion between the production and commercial land uses,often attributable to noisy training data or mixed land *** learnt from this exercise are discussed,and further research direction is proposed.

关键词： Data fusion land use land cover machine learning points of interest

Body Composition,Aerobic Fitness,Isokinetic Profile,and Vertical Jump Ability in Elite Male and Female Volleyball and Beach Volleyball Players

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Journal of science in sport and Exercise 2023年第4期5卷 385-395页

作者： Raul freire Matheus Hausen Glauber Pereira Alex Itaborahy Olympic Laboratory Brazil Olympic CommitteeRio de JaneiroBrazil Laboratory of Biomechanics and Motor Behavior Institute of Physical Education and SportsRio de Janeiro State UniversityRio de JaneiroBrazil

Purpose This study aimed to compare the physical attributes of male and female Volleyball and Beach Volleyball *** Fifty-five athletes from Volleyball(Male,n=19,age 27.3±6.1 years,body mass 93.2±9.9 kg,and height 196.8±7.4 cm and Female,n=16,age 28.0±5.6 years,body mass 76.9±8.8 kg,and height 179.9±5.8 cm)and Beach Volleyball(Male,n=10,age 26.8±3.4 years,body mass 92.9±9.9 kg,and height 195.3±7.9 cm and Female,n=10,age 31.1±6.2 years,body mass 74.6±8.5 kg,and height 180.9±6.0 cm)participated in the *** tests were performed in a single visit to the laboratory in the following order:body composition,vertical jump(squat and countermovement jump),isokinetic(knees and shoulders),and cardiopulmonary exercise *** variables were analyzed using a two-way ANOVA(sex and sport factors)for independent *** Beach Volleyball athletes presented lower body fat(P=0.03;Es=0.32)and higher maximal cardiorespiratory variables(VO2,HR,and vVO2max).Only flexion bilateral difference(knee)at 60°/s was affected by sex(P=0.002;Es=0.63).For shoulders,only dominant external/internal rotation ratio presented a significant interaction for sport and sex(P=0.05;Es=0.28).Regarding vertical jumps,Volleyball male players presented a greater elastic index than BV male players(P=0.002,Es=0.67).Conclusion Beach Volleyball players are thinner and have better cardiorespiratory fitness than Volleyball ***,they presented less use of elastic properties for vertical jumping and have a greater muscle imbalance in the hamstrings than Volleyball players.

关键词： Athlete profile Court VO2max Neuromuscular sex sport

Mathematical simulation of radial heat transfer in packed beds by pseudohomogeneous modeling

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Particuology 2011年第2期9卷 107-113页

作者： Rodrigo Béttega Marcos Flávio Pinto Moreira Ronaldo Guimaraes Corrêa José Teixeira freire Federal University of Uberlandia/school of Chemical Engineering-Av.Jo o Naves ávila 2121 Uberlandia-MGCEP 38400-902Brazil Western Paraná state University-Rua da Faculdade 645 Jardim La SalleToledo-PRCEP 85903-000Brazil Federal University of s o Carlos/Department of Chemical Engineering-Rod.Washington Luiz km 235 S o Carlos-SPCEP 13565-905P.O.Box 676Brazil

Uniform flow regime and constant effective thermal conductivity inside packed beds are commonly accepted in the evaluation of the fluid dynamics and heat transfer in such systems. However, several authors have confirmed the presence of an oscillatory velocity profile caused by the effective contribu~ tion of porosity profile in the fluid dynamic behavior of packed beds, which directly influences the heat transfer inside the beds. This paper describes the application of a pseudo-homogeneous mathematical model for describing heat transfer in packed beds with oscillatory profiles of velocity and porosity, using a radius-dependent model for effective thermal conductivity kr. several temperature profiles were obtained in a packed bed system with thermal source located on the wall. The simulated temperature and effective thermal conductivity obtained from simulations were compared with experimental data and calculation from a model based on uniform kr fitting. The results indicate that the proposed mathematical modeling was capable of better reDresenting the heat transfer in the packed bed.

关键词： Packed bedHeat transferPseudohomogeneous 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

sARs-CoV-2 infection in liver transplant recipients:A complex relationship

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World Journal of Gastroenterology 2021年第44期27卷 7734-7738页

作者： Ricardo Wesley Alberca Gil Benard Gabriela Gama freire Alberca Maria Notomi sato Laboratorio de Dermatologia e Imunodeficiencias(LIM-56) Departamento de Dermatologia e Institute de Medicina TropicalFaculdade de Medicina FMUSPUniversidade de São PauloSão Paulo 01246-903Brazil Laboratorio de Dermatologia e Imunodeficiencias(LIM-56) Departamento de DermatologiaFaculdade de Medicina FMUSPUniversidade de São PauloSão Paulo 01246-903Brazil

The recent manuscript reviewed investigations involving liver damage in coronavirus disease 2019(COVID-19)patients,and COVID-19 in patients with previous chronic hepatological diseases,such as patients with liver *** literature presents several conflicting results concerning the anti-sARs-CoV-2 response in patients with solid organ transplants,in liver transplant ***,we would like to humbly state a few points for consideration involving liver transplant recipients and COVID-19,such as the time since transplantation,comorbidities,and immunosuppressive regimens.

关键词： COVID-19 sARs-CoV-2 Liver transplant Immunosuppression Infection Comorbidities

Evaluation of Physicochemical,Microbiological and sensory stability of Frozen stored Vacuum-Packed Lamb Meat

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Journal of Integrative Agriculture 2013年第11期12卷 1946-1952页

作者： Rafaella de Paula Paseto Fernandes Maria Teresa de Alvarenga freire Celso da Costa Carrer Marco Antonio Trindade Department of Food Engeneering College of Animal Science and Food Engineering of UniversitySo Paulo(FZEA/USP)Avenida Duque of Caxias Norte225Jardim ElitePirassunungaSo Paulo 13.635-900Brazil Department of Food Engineering FZEA/USPPirassunungaSo Paulo 13.635-900Brazil Department of Animal science FZEA/USPPirassunungaSo Paulo 13.635-900Brazil

Nowadays, lamb meat represents only 7% of all meat produced in the world. In recent years the demand for standardized lamb meat cuts has been considered of great importance and the marketing occurs predominantly in the form of frozen cuts. Herewith, the main of this work was to evaluate the stability and safety of lamb meat during frozen storage. Meats were vacuum packed in high barrier multilayer plastic iflms and stored during 12 mon at （-18±1）℃. The meat stability was assessed by physical and chemical （lipid oxidation, objective color, pH value, cooking losses and instrumental texture）, microbiological （total count of psychrotrophic, coliform count at 45℃, coagulase-positive staphylococci and the presence of salmonella） and sensory analysis （acceptance test and visual evaluation）. The vacuum packed lamb meat remained stable as to most physical and chemical indexes. Microbiological indexes showed good stability throughout the storage period according to Brazilian legislation standards to pathogenic microorganisms. Although a signiifcant reduction in tenderness （shear force increase from 3 to 8 kg）, it showed a good sensorial acceptance for all attributes tested, including texture, with scores of around 7 （like moderately） during the 12 mon of storage. Therefore, it can be concluded that, under the conditions applied in this study, lamb meat presents a shelf life of at least 12 mon when stored at-18℃.

关键词： acceptance test Longissimus dorsi shelf life