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Multiphase modeling of fluid dynamic in ladle steel operations under non-isothermal conditions

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Journal of Iron and Steel Research International 2017年第9期24卷 888-900页

作者： H.gonzalez J.A.Ramos-Banderas E.Torres-Alonso g.Solorio-Diaz C.A.Hernández-Bocanegra graduate Program in Metallurgy Morelia Technological Institute(ITM)Morelia Michoacdn 58120Mexico graduate Program in Engineering Mechanical UMSNHMorelia Michoacdn 58140Mexico CATEDRAS CONACyT Benito JuarezCDMX 03940Mexico

A numerical simulation was performed to study the flow pattern,mixing time and open-eye slag produced by argon gas injection in an industrial scale steel ladle under non-isothermal *** liquid steel remains 5min before the injection,and thermal stratification and convective flows were *** different sequences in stages employing various argon-gas flow rates were *** the first case,a sequence with the highest flow rates of argon was applied,while in the second and the third sequences,the intermediate and the lowest flow rates of argon gas were used,*** determining the chemistry homogenization,the mixing time was computed and analyzed in all three *** was found that the cold steel is located near the walls while the steel with a high temperature is accumulated in the center of the ladle above the argon-gas *** higher and lower flows promote a faster chemistry homogenization owing to the secondary recirculations that are developed closer to the *** results from steel temperature drop show a good concordance with plant trial measurements.

关键词： Thermal stratification Mixing time Open-eye slag Ladle steelmaking Multiphase modeling

Solving the mystery of vanishing rivers in China

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National Science Review 2019年第6期6卷 1239-1246页

作者： Yichu Wang Jinren Ni Yao Yue Jiaye Li Alistair g.L.Borthwick Ximing Cai An Xue Li Li guangqian Wang The Key Laboratory of Water and Sediment Sciences Ministry of EducationCollege of Environmental Sciences and Engineering Peking University Beijing Innovation Center for Engineering Science and Advanced Technology Peking University State Key Laboratory of Plateau Ecology and Agriculture Qinghai University School of Water Resources and Hydropower Engineering Wuhan University State Key Laboratory of Hydroscience and Engineering Tsinghua University School of Engineering The University of Edinburgh Ven Te Chow Hydrosystems Lab Department of Civil and Environmental EngineeringUniversity of Illinois

A major controversy was sparked worldwide by a recent national water census claiming that the number of Chinese rivers with watersheds ≥100 km2was less than half the previous estimate of 50 000 rivers, which also stimulates debates on the potential causes and consequences. Here, we estimated the number of rivers in terms of stream-segmentation characteristics described by Horton, Strahler and Shreve stream-order rules, as well as their mixed mode for named rivers recorded in the Encyclopedia of Rivers and Lakes in *** a result, the number of ‘vanishing rivers’ has been found to be highly relevant to statistical specifications in addition to the erroneous inclusion of pseudo-rivers primarily generated in arid or frost-thaw areas. The modified Horton stream-order scheme reasonably depicts the configuration of complete natural streams from headwater to destination, while the Strahler largely projects the fragmentation of the named river networks associated with human aggregation to the hierarchical river systems.

关键词： vanishing rivers river network stream segmentation stream-order rules

Particles in a circulation loop for solar energy capture and storage

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Particuology 2019年第2期17卷 149-156页

作者： Q. Kang g. Flamant R. Dewil J. Baeyens H.L. Zhang Y.M. Deng KU Leuven Department of Chemical Engineering Process and Environmental Technology Lab. 2860 Sint-Katelijne-Waver Belgium Processes. Materials and Solar Energy Laboratory PROMES-CNRS 66120 Font Romeu France European Powder & Process Technology 3120 Tremelo Belgium Beijing University of Chemical Technology School of Life Science and Technology Beijing 10029 China

This study defines and assesses the selection ciiteria for suitable particulate materials to be used in an upflow bubbling fluidized bed (UBFB) or dense up-flow powder circulation system for solar energy capture and storage. The main criteria identified are based on the thermophysical and thermomechanical properties, attrition behavior, and the considerations of health and environmental hazards of the candidate powders. Finally, a cost comparison and tentative ranking of the different can didate powders is presented in addition to a weighted scoring. Significant scoring differences can be observed between the various materials. Olivine possesses the most favorable characteristics and appears to be the particulate material of choice for solid/gas suspension heat transfer fluids.

关键词： Concentrated solar power Particle-in-tube receiver Particle properties Selection criteria

Retinal nerve fiber layer and ganglion cell-inner plexiform layer thickness in children with obesity

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International Journal of Ophthalmology(English edition) 2016年第3期9卷 434-438页

作者： Selim Demir Samet ozer Sait Alim Alper günes Hüseyin Ortak Resul Yilmaz Department of Ophthalmology Faculty of Medicine Gaziosmanpasa University Tokat 60030 Turkey Department of Pediatrics Faculty of Medicine Gaziosmanpasa University Tokat 60030 Turkey

AIM：To evaluate retinal nerve fiber layer（RNFL）thickness analysis of peripapillary optic nerve head（PONH） and macula as well as ganglion cell-inner plexiform layer（gCIPL） thickness in obese children.· METHODS：Eighty-five children with obesity and 30 controls were included in the *** thicknesses of the PONH and macula of each subject＇s right eye were measured by high-resolution spectral-domain optic coherence tomography（OCT）.· RESULTS：The RNFL thicknesses of central macular and PONH were similar between the groups（all P 〉0.05）.The gCIPL thickness was also similar between the ***,the RNFL thickness of temporal outer macula were 261.7±13.7 and 268.9±14.3 μm for the obesity and the control group,respectively（P =0.034）.· CONCLUSION：Obesity may cause a reduction in temporal outer macular RNFL thickness.

关键词： ganglion cell-inner plexiform layer retinalnerve fiber layer thickness optical coherence tomography obesity

Dynamic Impact of High-Density Aluminum Foam

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Acta Mechanica Solida Sinica 2022年第2期35卷 198-214页

作者： Q.Peng J.Xie H.S.Ma X.Ling X.Liu Y.g.Wei LNM Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China School of Engineering and Technology China University of GeosciencesBeijing 100083China College of Engineering Peking UniversityBeijing 100871China

High-density aluminum foam can provide higher stiffness and absorb more energy during the impact Obtaining the constitutive law of such foam requires tri-axial tests with very high pressure,where difficulty may arise because the hydrostatic pressure can reach more than 30 *** this paper,instead of using tri-axial tests,we proposed three easier tests-tension,compression and shear to obtain the parameters of constitutive model(the Deshpande-Fleck model).To verify the constitutive model both statically and dynamically,we carried out addi-tional triaxial tests and direct impact tests,*** on the derived model,we performed finite element simulation to study the impact response of the present *** dimensional analysis,we proposed an empirical equation for a non-dimensional impact time the impact time divided by the time required for plastic wave travelling from the impact surface to the bottom surface,to det ermine the deformation charac teristic of the aluminum foam after *** the case with t_(d)≤1,the deformation tends to exhibit a shock-type characteristic,while for the case with t_(d)>5,the deformation tends to exhibit an upsetting-type characteristic.

关键词： High density aluminum Foam Deshpande-Fleck model Finite element method Impact analysis Plastic wave

Optical Design of ECEI Diagnostic System for HT-T Tokamak

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Plasma Science and Technology 2004年第1期6卷 2166-2171页

作者：王俊闻一之俞昌旋万宝年 N.C.Luhmann WangJian XiaZ.g. DepartmentofModernPhysics UniversityofScienceandTechnologyofChinaHefei230027China InstituteofPlasmaPhysics theChineseAcademyofSciencesHefei230031China DepartmentofAppliedScience UniversityofCaliforniaDavisCalifornia95616USA

Electron cyclotron emission imaging system in the frequency range of 95 gHz -125 gHz is going to be constructed for a two-dimensional diagnosis of the electron temperature profiles and fluctuations on the HT-7 Tokamak. The optical design for the ECEI diagnostic system is completed. Because of the superconducting technology used in HT-7, the vacuum chamber is rather thick (630 mm), the height of the horizontal windows is limited (maximum 450 mm), which constrains greatly the ECE imaging gaussian beam that passing through the windows. We here comes to make a design compromise between the number of the beams that can pass through the windows and the spatial resolution (around 1.1 cm). We also find that due to the field curvature of the optical system, the gaussian beams of edge channels are always overlapped. To flatten the field curvature, it is needed to insert a concave made of a material with a low refractive index (compared with the one used in the convex). But the suitable material has not been available so far, therefore the deterioration of the resolution in some channels (e.g. the edge channels) is acceptable.

关键词： electron cyclotron emission imaging optical design electron temperature and its fluctuations

Continuous live cell imaging of cellulose attachment by microbes under anaerobic and thermophilic conditions using confocal microscopy

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Journal of Environmental Sciences 2013年第5期25卷 849-856页

作者： Zhi-Wu Wang Seung-Hwan Lee James g.Elkins Yongchao Li Scott Hamilton-Brehm Jennifer L.Morrell-Falvey BioEnergy Science Center Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN 37831USA College of Food Agricultural and Environmental SciencesThe Ohio State University1328 Dover RdWoosterOH 44691USA National Institute of Advanced Industrial Science and Technology Biomass Refinery Research CenterHiroshimaJapan Department of Forest Biomaterials Engineering College of Forest and Environmental SciencesKangwon National UniversityChuncheon 200-701Korea

Live cell imaging methods provide important insights into the dynamics of cellular processes that cannot be derived easily from population-averaged *** the bioenergy field,much research is focused on fermentation of cellulosic biomass by thermophilic microbes to produce biofuels;however,little effort is dedicated to the development of imaging tools to monitor this dynamic biological *** is,in part,due to the experimental challenges of imaging cells under both anaerobic and thermophilic *** an imaging system is described that integrates confocal microscopy,a flow cell device,and a lipophilic dye to visualize *** to technical obstacles regarding suitable fluorescent markers,photodamage during imaging,and maintenance of environmental conditions during imaging are *** system was utilized to observe cellulose colonization by Clostridium thermocellum under anaerobic conditions at 60℃.This method enables live cell imaging of bacterial growth under anaerobic and thermophilic conditions and should be widely applicable to visualizing different cell types or processes in real time.

关键词： thermophile lipophilic dye cellulose biofuel confocal laser scanning microscopy biofilm

Effects of Current Stressing on Shear Properties of Sn-3.8Ag-0.7Cu Solder Joints

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Journal of Materials Science & Technology 2010年第8期26卷 737-742页

作者： X.J. Wang Q.L. Zeng Q.S. Zhu Z.g. Wang J.K. Shang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign Urbana IL 61801 USA

Effects of electromigration on microstructure, shear strength, and fracture behavior of solder joints were investigated by single-ball shear samples of eutectic Sn-3.8Ag-0.7Cu （SAC） joined by Cu plates at two sides. The electromigration tests were conducted at a current density of about 1.1×10^3 A/cm2 and a working temperature of about 83℃. The results showed that the shear strength and flow stress decreased greatly after current stressing. Such a decrease was associated with no significant loss of the fracture strain at short electromigration but a great reduction in the fracture strain after long-term current stressing. The variation of the fracture strain with the electromigration time was shown to result from the shift of the fracture surface from the center of the solder towards the intermetallic compound （IMC） interface at the cathode.

关键词： Strength Fracture strain Voids Solder

Higher Plant Proteins of Cyanobacterial Origin:Are They or Are They Not Preferentially Targeted to Chloroplasts?

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Molecular Plant 2014年第12期7卷 1797-1800页

作者： Roman g.Bayer Tina Kostler, Arpit Jain Simon Stael Ingo Ebersberger Markus Teige Department of Biochemistry and Cell Biology MFPLUniversity of ViennaDr Bohr Gasse 9A-1030 ViennaAustria CIBIV—Center for Integrative Bioinformatics Vienna MFPLDr.Bohr Gasse 9A-1030 ViennaAustria Department for Applied Bioinformatics Institute for Cell Biology and NeuroscienceGoethe UniversityMax-von-Laue Str.13D-60438 FrankfurtGermany VIB Department of Plant Systems Biology Ghent UniversityTechnologiepark 9279052 GentBelgium Department of Ecogenomics and Systems Biology University of ViennaAlthanstr 14A-1090 ViennaAustria Department of Applied genetics and Cell Biology University of Natural Resources and Life SciencesMuthgasse 18A-1190 ViennaAustria

Dear Editor, What does the evolutionary origin of a plant protein tell about its subcellular localization？ Naively thinking, one would assume that plant proteins that were originally encoded in the endosymbiont genome are targeted to the chloroplast. However, published data seem to support only a loose link between evolutionary origin and subcel- lular localization. About half of the Arabidopsis proteins with a detectable cyanobacterial ortholog are targeted to subcellular compartments other than the chloroplast （Martin et al., 2002）. H

关键词： Plant protein The origin of evolution chloroplast