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中国经济体制改革(二)

管理世界 1989年第1期 65-79页

作者：德怀特·h.珀金斯 ,陈越

本文的前一部分已于1988年第6期刊出,下面将其余部分载完,以飨读者。

关键词：人均收人服务业中华人民共和国服务行业服务部门统计数据农村人均国内生产总值资本存量质量指数价格指数物价指数资本积累率国家统计局城镇不均等乡村工业农业净产值农业生产净值城市人口

动态柱形空穴膨胀模型及其在侵彻问题中的应用(英文)

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高压物理学报 2006年第1期20卷 67-78页

作者：周辉文鹤鸣中国科技大学力学和机械工程系安徽合肥230027

对双线性应变强化材料的动态柱形空穴膨胀模型及其在侵彻问题中的应用进行了研究。通过采用相似变换求解塑性区控制方程,获得了动态柱形空穴膨胀中的弹塑性界面速度、径向应力分布、空穴表面应力的解。基于柱形空穴模型,推导了侵彻方程... 详细信息

对双线性应变强化材料的动态柱形空穴膨胀模型及其在侵彻问题中的应用进行了研究。通过采用相似变换求解塑性区控制方程,获得了动态柱形空穴膨胀中的弹塑性界面速度、径向应力分布、空穴表面应力的解。基于柱形空穴模型,推导了侵彻方程,并将其得到的预测结果与侵彻实验数据进行了比较。结果表明,模型的理论解与现有数据吻合得很好。结果还显示了材料的可压缩性和塑性强化模量对柱形空穴膨胀以及侵彻阻力的影响。

关键词：动态柱形空穴膨胀双线性强化材料性能侵彻

具有耗散接头的三维欧拉─伯努利杆系的特征频率

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应用数学和力学 1995年第8期16卷 677-698页

作者：威廉h.包尔森美国阿肯色州立大学数理及计算机科学系

本文计算了具有耗散接头的一般非共线的欧拉─伯努利或铁木辛柯杆系结构振动特征频率的传递矩阵．将允许结构是三维的，因此，一定要同时研究各种振动模式，包括纵向和扭转的振动。这种结构一般可以看作是由许多杆件首尾相接构成一条链... 详细信息

本文计算了具有耗散接头的一般非共线的欧拉─伯努利或铁木辛柯杆系结构振动特征频率的传递矩阵．将允许结构是三维的，因此，一定要同时研究各种振动模式，包括纵向和扭转的振动。这种结构一般可以看作是由许多杆件首尾相接构成一条链条。允许有各种不同的减振器，甚至有些减振器是本结构内部形成的．我们也允许在结构中采用不同材料，杆件也可以是不同宽度。本文证明了可以利用渐近估计方法来求得近似的特征频率。

关键词：特征频率耗散接头欧拉-伯努利杆系杆系结构

Preparation, Ch.racterization, Biological Activity and 3D molecular modeling of mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and Ru（Ⅲ） Complexes of Some Sulfadrug Sch.ff Bases

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Ch.nese Journal of Ch.mistry 2012年第4期30卷 881-890页

作者： EL-Gh.mry,h.A. Sakai,K. masaoka,S. EI-Baradie,K.Y Issa,R.m. Ch.mistry Department Faculty of ScienceTanta UniversityTantaEgypt Ch.mistry Department Faculty of ScienceKyushu UniversityFukuokaJapan Institute for molecular Science National Institutes of Natural SciencesJapan

mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and Ru（Ⅲ） complexes of Sch.ff bases derived from th. condensation of sulfaguanidine with.2,4-dih.droxy benzaldeh.de （h.1）, 2-h.droxy-l-naph.h.ldeh.de （h.2） and salicylaldeh.de （h.3） h.ve been synth.sized. Th. structures of th. prepared metal complexes were proposed based on elemental analysis, molar conductance, th.rmal analysis （TGA, DSC and DTG）, magnetic susceptibility measurements and spectroscopic tech.iques （IR, UV-Vis, and ESR）. In all complexes, th. ligand bonds to th. metal ion th.ough.th. azometh.ne nitrogen and a-h.droxy oxygen atoms. Th. structures of Pd（Ⅱ） complex 8 and Ru（Ⅲ） complex 9 were found to be polynuclear. Two kinds of stereoch.mical geometries; distorted tetrah.dral and distorted square py- ramidal, h.ve been realized for th. Cu（Ⅱ） complexes based on th. results of UV-Vis, magnetic susceptibility and ESR spectra wh.reas octah.dral geometry was predicted for Co（Ⅱ）, mn（Ⅱ） and Ru（Ⅲ） complexes. Ni（Ⅱ） com- plexes were predicted to be square planar and tetrah.dral and Pd（Ⅱ） complexes were found to be square planar. Th. antimicrobial activity of th. ligands and th.ir metal complexes was also investigated against th. gram-positive bac- teria Staph.lococcus aures and Bacillus subtilis and gram-negative bacteria, Esch.rich.a coli and Pesudomonas aeruginosa, by using th. agar dilution meth.d. Ch.oramph.nicol was used as standard compound. Th. obtained data revealed th.t th. metal complexes are more or less, active th.n th. parent ligand and standard. Th. X-ray crys- tal structure of h.3 h.s been also reported.

关键词： sulfaguanidine transition metal complexes spectral studies biological activity crystal structure mo- lecular modeling

Th. combined effects of grain and sample sizes on th. mech.nical properties and fracture modes of gold microwires

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Journal of materials Science & Tech.ology 2019年第1期35卷 76-83页

作者： h.K.Yang K.Cao Y.h.n m.Wen J.m.Guo Z.L.Tan J.Lu Y.Lu h.ng Kong Branch.of National Precious metals material Engineering Research.Center City University of Hong Kong Department of mech.nical and Biomedical Engineering City University of Hong Kong State Key Laboratory of Advanced Tech.ologies for Compreh.nsive Utilization of Platinum metals Sino-platinum Metals Co.Ltd Center for Advanced Structural materials City University of Hong Kong Shenzhen Research Institute

h.ll-Petch.relation was widely applied to evaluate th. grain size effect on mech.nical properties of metallic material. h.wever, th. sample size effect on th. h.ll-Petch.relation was always ignored. In th. present study, th. mech.nical test and microstructure observation were performed to investigate th. combined effects of grain and sample sizes on th. deformation beh.viors of gold microwires. Th. polycrystalline gold microwires with.diameter of 16 ?m were annealed at temperatures from 100°C to 600°C, leading to different ratios(t/d) of wire diameter(t) to grain size(d) from 0.9 to 16.7. Wh.n th. t/d was lower th.n 10, th. yield stress dropped fast and deviated from th. h.ll-Petch.relation. Th. free-surface grains played key role in th. yield stress softening, and th. volume fraction of free-surface grains increased with.th. t/d decreasing. Furth.rmore, th. effects of t/d on work-h.rdening beh.viors and fracture modes were also studied. With.t/d value decreasing from 17 to 3.4, th. samples exh.bited necking fracture and th. dislocation pile-ups induced work-h.rdening stage was gradually *** th. t/d value furth.r decreasing(t/d h. fracture mode turned into sh.ar failure, and th. work-h.rdening capability lost. As th. gold microwire for wire bonding is commonly applied in th. packaging of integrated circuit ch.ps, and th. fabrication of microwire suffers multi-pass cold-drawing and annealing treatments to control th. grain size. Th. present study could provide instructive suggestion for gold microwire fabrication and bonding processes.

关键词： Gold microwire Wire bonding Tensile testing Grain size h.ll-Petch relationsh.p

Lead Concentration in h.ng Kong Roadside Dust after Reduction of Lead Level in Petrol

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Biomedical and Environmental Sciences 1989年第2期2卷 131-140页

作者： G.Y.S.Ch.N V.W.D.Ch.I m.h.WONG Department of Biology Hong Kong Baptist College224 Waterloo RoadKowloonHong Kong

Samples of roadside dust were collected from 30 sites in h.ng *** total concentrations of 10 metals in th. samples were analyzed,and th. correlation coefficients among th. metal contents and th. annual average daily traffic(AADT)in 1986 were *** was found to h.ve a significant correlation(Ph.*** correlation was found between Al, Ba,Cd,Cr,Cu,Fe,mn,Ni,and Zn with.respect to AADT.A general decrease in th. level of Pb in roadside dust in th. past few years h.s been observed since th. reduction in th. level of lead in petrol.1989 Academic Press,Inc.

关键词： h. In Ba Lead Concentration in h.ng Kong Roadside Dust after Reduction of Lead Level in Petrol Pb

Path.ay-selective suppression of ch.mokine receptor signaling in B cells by LPS th.ough.downregulation of PLC-b2

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Cellular & molecular Immunology 2010年第6期7卷 428-439页

作者： Aiko-Konno Sh.rakawa Fang Liao h.ngwei h.Zh.ng mich.el N h.drick Satya P Singh.Dianqing Wu Josh.a m Farber Inflammation Biology Section Laboratory of Molecular ImmunologyNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMDUSA Department of Ph.rmacology Yale University School of MedicineNew HavenCTUSA

Lymph.cyte activation leads to ch.nges in ch.mokine receptor *** are limited data,h.wever,on h.w lymph.cyte activators can alter ch.mokine signaling by affecting downstream *** h.poth.sized th.t B cell-activating agents migh. alter ch.mokine responses by affecting downstream signal transducers,and th.t such.effects migh. differ depending on th. *** found th.t activating mouse B cells using eith.r anti-Igm or lipopolysacch.ride(LPS)increased th. surface expression of CCR6 and CCR7 with.large increases in ch.motaxis to th.ir cognate *** contrast,wh.le anti-Igm also led to enh.nced calcium responses,LPS-treated cells sh.wed only small ch.nges in calcium signaling as compared with.cells th.t were fresh.y *** particular interest,we found th.t LPS caused a reduction in th. level of B-cell ph.sph.lipase C(PLC)-b2 mRNA and *** obtained using PLC-b22/2 mice sh.wed th.t th. b2 isoform mediates close to one-h.lf th. ch.mokine-induced calcium signal in resting and anti-Igm-activated B cells,and we found th.t calcium signals in th. LPS-treated cells were boosted by increasing th. level of PLC-b2 using transfection,consistent with.a functional effect of downregulating ***,our results sh.w activator-specific effects on responses th.ough.B-cell ch.mokine receptors th.t are mediated by quantitative ch.nges in a downstream signal-transducing protein,revealing an activity for LPS as a downregulator of PLC-b2,and a novel mech.nism for controlling ch.mokine-induced signals in lymph.cytes.

关键词： B cells calcium ch.mokine ch.motaxis GPCR

Transient growth.in Poiseuille-Rayleigh.Bénard flows of binary fluids with.Soret effect

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Applied math.matics and mech.nics(English.Edition) 2016年第9期37卷 1203-1218页

作者： Jun h. D.h.NRY h.BENh.DID Xieyuan YIN Institute of Applied Ph.sics and Computational math.matics Beijing 100088China Laboratoire de mecanique des Fluides et d'Acoustique CNRS/Universitd de LyonEcole Centrale de Lyon/universite Lyon 1/INSA de LyonECL36 avenue Guy de Collongue69134 Ecully CedexFrance Department of modern mech.nics University of Science and Technology of ChinaHefei 230027China

Th. transient growth.due to non-normmity is investigated for th. Poiseuille- Rayleigh.Benard problem of binary fluids with.th. Soret effect. For negative separation factors such.as ψ = -0.1, it is found th.t a large transient growth.can be obtained by th. non-normal interaction of th. two least-stable-modes, i.e., th. upstream and downstream modes, wh.ch.determine th. linear critical boundary curves for small Reynolds numbers. Th. transient growth.is so strong th.t th. optimal energy amplification factor G（t） is up to 10^2 - 10^3. Wh.le for positive separation factors such.as ψ = 0.1, th. transient growth.is weak with.th. order O（I） of th. amplification factor, wh.ch.can even be computed by th. least-stable-mode. h.wever, for both.cases, th. least-stable-mode can govern th. long-term beh.vior of th. amplification factor for large time. Th. results also sh.w th.t large Reynolds numbers h.ve stabilization effects for th. maximum amplification with.n moderate wave number regions. meanwh.le, much.small negative or large positive separation factors and large Rayleigh.numbers can enlarge th. maximum transient growth.of th. pure streamwise disturbance with.th. wavenumber α= 3.14. moreover, th. initial and evolutionary two-dimensional spatial patterns of th. large transient growth.for th. pure streamwise disturbance are exh.bited with.a plot of th. velocity vector, spanwise vorticity, temperature, and concentration field. Th. initial th.ee-layer cell vorticity struc- ture is revealed. Wh.n th. amplification factor reach.s th. maximum Gmax, it develops into one cell structure with.large amplification for th. vorticity strength.

关键词： binary fluid Soret effect transient growth Poiseuille-Rayleigh.Benard flow

Position dependent circuit model for th.n avalanch. ph.todiodes

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Frontiers of Optoelectronics 2013年第2期6卷 194-198页

作者： moh.mmad h. AKBARI moh.en JALALI Sch.ol of Engineering Shahed University Tehran *** Iran

Th.s paper presents a circuit model for th.n avalanch. ph.todiodes （APDs）. In th.s model, th. nonuniformity of th. electric filed in th. multiplication region is modeled using a stepwise meth.d. Th. model also tries to take th. effects of carrier＇s position dependent properties, like carder＇s dead length.and th. h.story of carder＇s previous ionization into account by developing an effective electric field in th. multiplication region. Th. output ph.tocurrent and multiplication gain obtained from th. proposed model for different length. of th. multi- plication region ach.eve a good agreement in comparison with.available experimental data. In addition, calculated excess noise factor reveals th. model ability for noise and sensitivity analysis.

关键词： avalanch. ph.todiode (APD) circuit model- ing multiplication gain nonuniform electric field excess noise factor