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Mathematical model of micropolar fluid in two-phase immiscible fluid flow through porous channel

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Applied Mathematics and Mechanics(English Edition) 2018年第7期39卷 993-1006页

作者： p.K.YADAV S.JAISWAL b.D.ShaRMA Department of Mathematics Motilal Nehru National Institute of Technology Allahabad

This paper is concerned with the flow of two immiscible fluids through a porous horizontal channel. The fluid in the upper region is the micropolar fluid/the Eringen fluid, and the fluid in the lower region is the Newtonian viscous fluid. The flow is driven by a constant pressure gradient. The presence of micropolar fluids introduces additional rotational parameters. Also, the porous material considered in both regions has two different permeabilities. A direct method is used to obtain the analytical solu- tion of the concerned problem. In the present problem, the effects of the couple stress, the micropolarity parameter, the viscosity ratio, and the permeability on the velocity profile and the microrotational velocity are discussed. It is found that all the physical parameters play an important role in controlling the translational velocity profile and the microrotational velocity. In addition, numerical values of the different flow parameters are computed. The effects of the different flow parameters on the flow rate and the wall shear stress are also discussed graphically.

关键词： micropolar fluid immiscible fluid porous medium couple stress microp=olarity parameter

Synthesis,characterization and thermolysis of lanthanide metal nitrate complexes with 1,10-phenanthroline,part-95

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Journal of Rare Earths 2014年第6期32卷 545-552页

作者： Nibha b.p.baranwal Gurdip Singh Constantin G.Daniliuc Department of Chemistry DDU Gorakhpur University Organisch–Chemisches Institut Universitat Munster

The nitrate complexes of cerium, praseodymium and neodymium with 1,10-phenanthroline （phen） of general formula [Ln（phen）2（NO3）2（H2O）2]·NO3 （where, Ln=Ce, pr and Nd） were prepared and characterized by X-ray crystallography. Thermolysis of these complexes was investigated by simultaneous thermogravimetry （TG） and differential thermal analysis （DTA）. Isothermal TG was taken to evaluate the kinetic parameters using model fitting as well as model free isoconversional methods. The thermolytic pathways were also suggested, which involves decomposition followed by ignition. All the three complexes had coordination number ten and showed multistep decompositions. In order to evaluate the response of rapid heating, ignition delay （Di） measurements were undertaken. The activation energies for ignition were found to decrease in the order： Nd〉pr〉Ce.

关键词： crystal structure metal nitrate kinetics isoconversional model fitting ignition delay rare earths

Thermophysical properties of iridium at finite temperature

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Chinese physics b 2016年第11期25卷 404-411页

作者： priyank Kumar N K bhatt p R Vyas V b Gohel Department of Science Government PolytechnicGandhinagar Department of physics Sardar Patel University Department of physics School of Science Gujarat University

The bulk properties of materials in an extreme environment such as high temperature and high pressure can be understood by studying anharmonic effects due to the vibration of lattice ions and thermally excited *** this spirit,in the present paper,anharmonic effects are studied by using the recently proposed mean-field potential（MFp） approach and Mermin functional which arise due to the vibration of lattice ions and thermally excited electrons,*** MFp experienced by a wanderer atom in the presence of surrounding atoms is constructed in terms of cold energy using the local form of the *** have calculated the temperature variation of several thermophysical properties in an extreme environment up to melting *** results of our calculations are in excellent agreement with the experimental findings as well as the theoretical results obtained by using first principle *** conclude that presently used conjunction scheme（MFp＋pseudo potential） is simple computationally,transparent physically,and accurate in the sense that the results generated are comparable and sometimes better than the results obtained by first principle *** pseudopotential used is transferable to extreme environment without adjusting its parameters.

关键词： extreme experienced melting presently excited thermally sometimes understood comparable conclude

Synthesis,characterization and application of pVA/ionic liquid mixed matrix membranes for pervaporation dehydration of isopropanol

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Chinese Journal of Chemical Engineering 2017年第10期25卷 1402-1411页

作者： Ganesh b.Thorat Smita Gupta Z.V.p.Murthy Department of Chemical Engineering Sardar Vallabhbhai National Institute of Technology Surat 395007 Gujarat India

In this study,polyvinyl alcohol(pVA)–ionic liquid(IL) membranes were prepared for the separation of isopropyl alcohol(IpA)–water azeotropic mixtures by ***-IL composite membranes were prepared by simple solvent evaporation method using four ILs,viz.,1-n-butyl-3-methylimidazolium chloride(bMIMCl),1-hexyl-3-methylimidazolium chloride(HMIMCl),1-hexyl-3-methylimidazolium tetra fluoroborate(HMIMbF4) and 1-octyl-3-methylimidazolium chloride(OMIMCl).Three ILs were used to study the effect of alkyl chain on the pervaporation *** study had focused on the effect feed water concentration from 10%–40%and effect of feed temperature from 50–80°*** properties of all the membranes were studied using Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy(SEM) and contact angle *** Arrhenius activation energies for permeation were estimated to be in the range 4–12 kJ·mol-1 from the temperature dependent permeation values.

关键词： Composite membranes Ionic liquids Dehydration Isopropanol pervaporation

Microstructures and Mechanical properties of Al/Mg Alloy Multilayered Composites produced by Accumulative Roll bonding

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Journal of Materials Science & Technology 2011年第1期27卷 15-21页

作者： H.S. Liu b. Zhang G.p. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education School of Materials & Metallurgy Northeastern University Shenyang 110004 China

Al/Mg alloy multilayered composites were produced successfully at the lower temperature（280 C） by accumulative roll bonding（ARb） processing *** microstructures of Al and Mg alloy layers were characterized by scanning electron microscopy and transmission electron *** hardness and three-point bending tests were conducted to investigate mechanical properties of the *** is found that Vickers hardness,bending strength and stiffness modulus of the Al/Mg alloy multilayered composite increase with increasing the ARb *** and crack propagation along the interface are the two main failure modes of the multilayered composite subjected to bending *** and fracture mechanisms of the composite are analyzed.

关键词： Accumulative roll bonding(ARb) Al/Mg alloy multilayered composite Ultra-fine grains hardness bending properties

Application of phase diagram calculations to development of new ultra-high temperature structural materials

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中国有色金属学会会刊：英文版 2007年第6期17卷 1396-1404页

作者：杨莹 b.p. bewlay 陈双林 Y.A. Chang CompuTherm LLC Madison Wisconsin 53719 USA General Electric Global Research Schenectady New York 12301 USA Department of Materials Science and Engineering University of Wisconsin-Madison Madison Wisconsin 53705 USA

In-situ refractory metal intermetallic composites(RMICs) based either on (Nb, Si) or (Mo, Si, b) are candidate materials for ultra-high temperature applications (>1400 ℃). To provide a balance of mechanical and environmental properties, Nb-Si composites are typically alloyed with Ti and Cr, and Mo-Si-b composites are alloyed with Ti. phase diagrams of Nb-Cr-Ti-Si and Mo-Si-b-Ti, as prerequisite knowledge for advanced materials design and processing development, are critically needed. The phase diagrams in the metal-rich regions of multicomponent Nb-Cr-Ti-Si and Mo-Si-b-Ti were rapidly established using the Calphad (Calculation of phase diagram) approach coupled with key experiments. The calculated isotherms, isopleths, and solidification paths were validated by experimental work. The important heterogeneous multiphase equilibria in both quaternary systems identified will offer engineers the opportunity to develop materials with a balance of properties for high-temperature applications.

关键词：金属间化合高温材料 Mo-Si-b-Ti Nb-Cr-Si-Ti

Refractive Index and Electronic polarizability of Ternary Chalcopyrite Semiconductors

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Chinese physics Letters 2015年第12期32卷 147-151页

作者： KUMAR V. SINha Anita SINGH b.p. SINha A.p. Jha V. Department of Electronics Engineering Indian School of Mines

Simple models are proposed for the calculation of refractive index n and electronic polarizability α of AⅠbⅢC2Ⅵ and AⅡbⅣC2Ⅴ compounds of groups of chalcopyrite semiconductors from their energy gap data. The values family and 12 compounds of AⅡbⅣC2Ⅴ family are calculated for the work. The proposed models are applicable for the whole range of energy gap materials. The calculated values are compared with the available experimental and reported values. A fairly good agreement between them is obtained.

关键词： Te In Refractive Index and Electronic polarizability of Ternary Chalcopyrite Semiconductors

Expression of E-cadherin and α-catenin in a varicocele-induced infertility rat model

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Asian Journal of Andrology 2011年第3期13卷 470-475,514页

作者： Hong Koo ha Hyun Jun park Nam Cheol park Department of Urology Pusan National University School of Medicine Busan 602739 Korea Medical Research Institute Pusan National University Hospital Busan 602739 Korea

The roles of E-cadherin and α-catenin were evaluated in the development of varicocele-induced infertility. Analysis of the association between the expression of E-cadherinla-catenin and clinical/pathological parameters was performed. Thirty lO-week-old male rats （experimental group） were used for the experiments; the left renal vein was ligated to form a varicocele. The abdomen was incised in 30 rats （control group） and no procedure was performed on 10 rats （baseline group）. The weights of the left testis, serum reactive oxygen species （ROS）, testosterone, luteinizing hormone （LH）, follicle-stimulating hormone （FSH） and degenerative changes in the seminiferous tubules after 4 and 8 weeks were recorded. The expression of E-cadherin and α-catenin was evaluated by immunohistochemical （IHC） staining and Western blot analysis. The ROS increased in the 8-week experimental group, compared with the baseline and control groups （p〈0.001 for both）. Additionally, FSH significantly increased in the 4- and 8-week experimental group compared with the control groups （p= 0.013 and p= 0.032, respectively）. The ratio of degenerative changes in the seminiferous tubules of the experimental groups increased. The IHC staining showed that the expression of E-cadherin and a-catenin decreased in the 4- and 8-week experimental groups. Similar to the IHC staining, the experimental group had decreased reactivity on Western blot analysis. The expression of E-cadherin and a-catenin was significantly associated with the ROS and degenerative changes in the seminiferous tubules. The results of this study suggest that damage to the blood-testis barrier （bTb） is associated with varicocele-induced male infertility, and that ROS may cause damage to the bTb.

关键词： α-catenin blood-testis barrier E-cadherin varicocele infertility

Are hyoliths palaeozoic lophophorates?

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National Science Review 2020年第2期7卷 453-469页

作者： Fan Liu Christian b Skovsted Timothy p Topper Zhifei Zhang Degan Shu State Key Laboratory of Continental Dynamics Shaanxi Key Laboratory of Early Life and Environments Department of Geology Northwest University Department of palaeobiology Swedish Museum of Natural History

The phylogenetic position of hyoliths has long been unsettled, with recent discoveries of a tentaculate feeding apparatus(‘lophophore’) and fleshy apical extensions from the shell(‘pedicle’) suggesting a lophophorate affinity. Here, we describe the first soft parts associated with the feeding apparatus of an orthothecid hyolith, Triplicatella opimus from the Chengjiang biota of South China. The tuft-like arrangement of the tentacles of T. opimus differs from that of hyolithids, suggesting they collected food directly from the substrate. A reassessment of the feeding organ in hyolithids indicates that it does not represent a lophophore and our analysis of the apical structures associated with some orthothecids show that these represent crushed portions of the shell and are not comparable to the brachiopod pedicle. The new information suggests that hyoliths are more likely to be basal members of the lophotrochozoans rather than lophophorates closely linked with the phylum brachiopoda.

关键词： orthothecid the Chengjiang Lagerst¨atte Cambrian soft parts lophophore