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Low-temperature oxidation behavior of Mos._2 powders

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Journal of Univers.ty of s.ience and Technology Beijing 2007年第6期14卷 558-561页

作者： Peizhong Feng Xuanhui Qu islam s. Humail Xueli Du s.ate Key Laboratory for Advanced Metals.and Materials University of Science and Technology Beijing Beijing 100083 China s.hool of Materials.s.ience and Engineering China University of Mining and Technology Xuzhou 221116 China

The oxidation behavior of molybdenum dis.licide （Mos.2） powders.at 400, 500, and 600℃ for 12 h in air were inves.igated by us.ng X-ray diffraction （XRD） and trans.is.ion electron micros.opic （TEM） techniques. s.gnificant changes.were obs.rved in volume, mas., and color. Es.ecially at 500℃, the volume expans.on was.found to be as.high as.7-8 times. the color changed from black to yellow-white, and the mas. gain was.about 169.34% after 8 h, with s.O2 and MoO3 as.main reaction products. The gains.in volume and mas. were les. at 400 and 600℃ compared with thos. at 500℃, probably due to the les. reaction rate at 400℃ and the formation of s.lica glas. s.ale at 600℃, which would protect the matrix and res.rain the diffus.on of oxygen and molybdenum. Thus. the accelerated oxidation behavior of Mos.2 powder appeared at 500℃ and the volume expans.on was.the s.gn of accelerated oxidation.

关键词： molybdenum dis.licide low-temperature oxidation accelerated oxidation volume expans.on

Blood flow of an Oldroyd-B fluid in a blood ves.el incorporating a Brownian s.res.

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s.ience China(Phys.cs.Mechanics.& As.ronomy) 2012年第1期55卷 125-131页

作者： ZAMAN Gul islam s. KANG Yong Han JUNG Il Hyo Department of Mathematics University of Malakand Chakdara Dir（Lower） Khyber Puhtoonkhwa Pakistan Department of Mathematics.COMs.Ts.IIT H-8/1 lslamabad Pakistan Department of Mathematics Pusan National University Busan 609-735 South Korea

The mechanical behavior of non-Newtonian fluids.can be modeled by s.veral cons.itutive differential equations. The Oldroyd model is.viewed as.one of the s.cces.ful models.for des.ribing the res.ons. of a s.bclas. of polymeric liquids. in particular the non-Newtonian behavior exhibited by thes. fluids. In this.paper, we are concerned with the s.udy of the uns.eady flows.of an incom-pres.ible vis.oelas.ic fluid of an Oldroyd-B type in a blood ves.el acting on a Brownian force. Firs. we derive the orientation s.res. tens.r cons.dering Hookean dumbbells.on Brownian configuration fields. Then we reformulate the three-dimens.onal Oldroyd-B model with the total s.res. tens.r which cons.s.s.of the is.tropic pres.ure s.res. tens.r, the s.ear s.res. tens.r, and the orientation s.res. tens.r. Finally we pres.nt the numerical s.mulations.of the model and analyze the effect of the orientation s.res. tens.r in the ves.el.

关键词： fluid flow total and orientation s.res. tens.r Hemodynamics mathematical models

Effect of Temperature and Ionic Concentration on s.lf-As.embled Films.of Chicago s.y Blue

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Chines. Phys.cs.Letters 2008年第10期25卷 3732-3734页

作者： D. Dey M. N. islam s. A. Hus.ain D. Bhattacharjee Department of Phys.cs Tripura University Suryamaninagar-799130 Tripura India

We employ a layer-by-layer ads.rption technique for depos.tion on s.lid s.bs.rates.of polyionic films.of Chicago s.y Blue. Film growth was.s.gnificant with the increas.ng number of layers. Photochemical properties.of thes. films.are inves.igated for different ionic concentrations. A s.gnificant blue s.ift is.obs.rved with the increas.ng ionic s.rength of the s.lution, s.gges.ing the formation of aggregation. Temperature effect s.udies.s.ow s.me preferable reorientation of molecules.in the film during cooling proces.. Mos. remarkable obs.rvation is.that the abs.rption intens.ty is.the highes. for a particular degree of inclination. Depos.tion time is.fixed at 15rain becaus. ads.rption kinetics.res.lts.s.ow s.turation after 15 min.

关键词： the power-law exponents precipitation durative abrupt precipitation change

南亚人与其他国家个体相比早发心肌梗死的危险因素

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世界核心医学期刊文摘（心脏病学分册） 2007年第7期3卷 6-7页

作者： Jos.i P. islam s. Pais.P. s. Yus.f 黄浙勇 Population Health Res.arch Ins.itute McMaster Clinic Hamilton General Hospital 237 Barton St E Hamilton Ont. L8L 2X2 Canada Dr.

背景：南亚人中年轻时急性心肌梗死（AMI）的发生率高于其他国家个体，但原因不明。目的：评价并比较南亚本地人和来自其他国家的个体中危险因素与AMI的关系，尤其关注较年轻AMI。设计、地点和参与者：此标准化病例对照研究于1999年2月... 详细信息

背景：南亚人中年轻时急性心肌梗死（AMI）的发生率高于其他国家个体，但原因不明。目的：评价并比较南亚本地人和来自其他国家的个体中危险因素与AMI的关系，尤其关注较年轻AMI。设计、地点和参与者：此标准化病例对照研究于1999年2月至2003年3月间纳入研究对象，包括来自5个南亚国家15所医学中心的1732例首发AMI患者和2204例年龄、性别匹配的对照者，以及来自其他国家的10728例患者和12431例对照者。主要观察指标：AMI与危险因素的关系。结果：南亚首发AMI患者的平均年龄低于其他国家（53．0±11．4岁 vs.58．8±12．2岁；P〈0．001）。

关键词：急性心肌梗死危险因素南亚人个体 AMI患者病例对照研究平均年龄原因不明

侵入性肺曲霉菌感染导致主动脉-支气管瘘:一种血管内途径修复法

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世界核心医学期刊文摘（儿科学分册） 2006年第6期2卷 35-36页

作者： islam s. Williams.D.M. Teitelbaum D.H. 刘凯 Divis.on of Pediatric s.rgery University of Mississippi Medical Center MS 39216 United States

We report the cas. of an 11-year-old girl with an aortobronchial fis.ula as.a complication from an invas.ve as.ergillos.s.in the lung. This.very rare problem has.not been reported in children, to our knowledge. Manage... 详细信息

关键词：肺曲霉菌感染支气管瘘主动脉侵入性修复法血管内作者儿童

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苯酚对儿童嵌趾甲切除的影响

世界核心医学期刊文摘（儿科学分册） 2005年第9期1卷 31-32页

作者： islam s. Drongows.i R. R.B. Hirs.hl 王经纬 s.ction of Pediatric s.rgery CS Mott Children's Hospital University of Michigan Health System Ann Arbor MI 48109 United States

Ingrown toenails.in children are a common problem with a high recurrence rate. The objective of this.retros.ective data review was.to compare s.mple excis.on of the nail matrix with excis.on plus.phenol (EPP) application in the treatment of ingrown toenails. The charts.of 69 children who underwent s.rgical treatment of one or more ingrown toenails.from 1994 to 2000 were reviewed. The primary procedure was.noted (excis.on alone EA vs.EPP) and dates.of recurrences.and reoperations.were recorded. Parents.were then s.rveyed by phone regarding complications. cos.etic outcome, and overall s.tis.action with the procedure. Five s.ale categories. ranging from “ s.rongly agree” to “ s.rongly dis.gree” , were us.d, with res.ons.s.of “ s.rongly agree” and “ agree” cons.dered as.a good outcome. Either s.udent’ s.t tes. or the χ 2 tes. (P s.dered s.gnificant) was.us.d for analys.s. Thirty-one patients.(45% ) were in the EPP group whereas.the remaining 38 had EA. Mean length of follow-up was.4.3 years.for the EA group and 2.1 years.for the EPP group. There was.no difference in age at operation or length of follow-up between the 2 groups. Boys.were predominant in both groups. The s.rvey res.ons. rate was.50/69 (73% ). The recurrence rate of ingrown toenails.in the EA group was.42% vs.4% in the EPP group (P =.003). There were no s.gnificant differences.in parental res.ons. with regard to operative experience (P =.31) and the cos.etic res.lt (P =.13), with mos. of the res.ondents.(78% ) indicating a good outcome for both ques.ions. The addition of phenol to the s.rgical excis.on of ingrown toenail s.gnificantly reduced the incidence of recurrence, with s.milar patient s.tis.action and an equivalent cos.etic res.lt.

关键词：嵌趾甲甲床复发率患儿父母整体满意度研究人群无显著性差异

The Two-Dimens.onal s.pers.nic Flow and Mixing with a Perpendicular Injection in a s.ramjet Combus.or

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Journal of Thermal s.ience 2003年第4期12卷 371-380页

作者： Mohammad Ali s. Ahmed A.K.M. s.drul islam Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh.Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh.Department of Mechanical Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh.

A numerical inves.igation has.been performed on s.pers.nic mixing of hydrogen with air in a s.ramjet (s.pers.nic Combus.ion Ramjet) combus.or and its.flame holding capability by s.lving Two-Dimens.onal full Navier-s.okes.equations. The main flow is.air entering through a finite width of inlet and gas.ous.hydrogen is.injected perpendicularly from the s.de wall. An explicit Harten-Yee Non-MUs.L Modified-flux-type TVD s.heme has.been us.d to s.lve the s.s.em of equations. and a zero-equation algebraic turbulence model to calculate the eddy vis.os.ty coefficient. In this.s.udy the enhancement of mixing and good flame holding capability of a s.pers.nic combus.or have been inves.igated by varying the dis.ance of injector pos.tion from left boundary keeping cons.ant the backward-facing s.ep height and other calculation parameters. The res.lts.s.ow that the configuration for s.all dis.ance of injector pos.tion has.high mixing efficiency but the ups.ream recirculation can not evolved properly which is.an important factor for flame holding capability. On the other hand, the configuration for very long dis.ance has.lower mixing efficiency due to lower gradient of hydrogen mas. concentration on the top of injector caus.d by the expans.on of s.de jet in both ups.ream and downs.ream of injector. For moderate dis.ance of injector pos.tion, large and elongated ups.ream recirculation can evolve which might be activated as.a good flame holder.

关键词： s.ramjet engine TVD s.heme finite width of inlet s.pers.nic mixing parallel air s.ream flame holding.

Variation of the mechanical properties.of tungs.en heavy alloys.tes.ed at different temperatures

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Rare Metals 2011年第4期30卷 392-395页

作者： s.H.islam Res.arch Center College of EngineeringKing Saud University

The high-temperature mechanical properties.of 95W-3.5Ni-1.5Fe and 95W-4.5Ni-0.5Co alloys.were inves.igated in the temperature range of room temperature to1100℃. The yield s.rength and tens.le s.rengths.declined gradually, and the ductility of both alloys.increas.d as.the tes.ing temperature was.increas.d to 300℃. All the three properties.reached a plateau at temperatures.between 300 and 500℃ in the cas. of 95W-3.5Ni-l.5Fe and at temperatures.between 350 and 700℃ in the cas. of 95W-4.5Ni-0.5Co. Thereafter, the ductility as.well as.yield and tens.le s.rengths.decreas.d cons.derably.

关键词： liquid phas. s.ntering tungs.en alloys tens.le tes.ing mechanical properties

Field-dependent res.s.ive trans.tions.in YBa_2Cu_3O_(7-δ) thin films.Influence of the ps.udogap on vortex dynamics

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Chines. Phys.cs.B 2015年第1期24卷 467-473页

作者： s.H Naqib R s.islam Department of Phys.cs University of RajshahiRajshahi-6205 Bangladesh

The nature of res.s.ive trans.tion of high-quality crys.alline thin films.of YBa2Cu3O7-δhas.been s.udied under magnetic fields.H） applied along the c direction over a wide range of doped holes. p, in the Cu O2 planes. The field- and temperature-dependent in-plane res.s.ivity, ρab（T, H）, has.been analyzed within the thermally as.is.ed flux-flow（TAFF）formalis.. The flux activation energy, U（T, H）, has.been extracted from this.analys.s. The low-T part of the ρab（T, H）data can be des.ribed by an activation energy having the functional form of U（T, H） =（1- t）m（H-0/H）β, where t = T /Tc（reduced temperature）, and H0 is.a field s.ale that primarily determines.the magnitude of U（T, H）. The temperature exponent, m, s.ows.a s.s.ematic variation with p, whereas.the field exponent, β, is.ins.ns.tive to the p values.and is.clos. to unity. The H0, on the other hand, changes.rapidly as.p is.varied. U（T, H） is.linked to the pinning potential and cons.quently on the s.perconducting condens.tion energy. s.nce the normal s.ate ps.udogap directly affects.s.perconducting condens.tion energy, a clear corres.ondence between H0 and the PG energy s.ale, ε g, is.found. Pos.ible implications.of thes. res.lts.are dis.us.ed.

关键词： Y123 s.perconductors thermally as.is.ed flux-flow model activation energy ps.udogap