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Journal of energy Chemistry 2002年第Z2期 165-170页

作者： Meisheng Liang, Chunhu Li, Hanxian Guo, Kechang XieState Key laboratory of Cl Chemistry and Technology, Architecture and Environmental College, Research Institute of Coal Chemical Engineering, Taiyuan University of Technology, Taiyuan 03.024, china

The adsorptions of COS, H2S and O2 were investigated over the TGH catalyst in this paper. It was found that the numbers of basic centers and basic intensities were reduced over the deactivated TGH catalyst. The PT-IR results of COS+H2S+O2 co-adsorption on the TGH catalyst show that the main causes of catalyst deactivation is the formation of element sulfur and trace sulfate.

关键词： 

The improvement of turbulence modeling for the aerothermal computation of hypersonic turbulent boundary layers

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Science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 369-379页

作者： DONG Ming & ZHOU Heng Department of Mechanics,Tianjin University,Tianjin 3.0072,china 1. Department of Mechanics Tianjin University Tianjin 300072 China

The engineering computation of turbulent flows is mainly based on turbulence modeling,however,accurate aerothermal computation of hypersonic turbulent boundary layers is still a not well-solved problem. Aerothermal computation for turbulent boundary layers on a supersonic or hypersonic blunt cone with small bluntness is done firstly by using both direct numerical simulation and BL model,and seven different cases are investigated. Then the results obtained by the two methods are compared,and the reason causing the differences is found to be the incorrect assumption in the turbulence modeling that the ratio between eddy heat conductivity and eddy viscosity is constant throughout the whole boundary layer. Based on certain theoretical arguments,a method of modifying the expression of eddy heat conductivity in the region surrounding the peak location of the turbulent kinetic energy is proposed,which is verified to be effective,at least for the seven cases investigated.

关键词： hypersonic turbulent boundary layer aerothermal supersonic cone direct numerical simulation(DNS) BL model coefficient of eddy heat conductivity

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爆炸法合成石墨烯(英文)

新型炭材料 2011年第1期26卷 21-25页

作者：王灿詹亮乔文明凌立成华东理工大学化学工程国家重点实验室

以石墨氧化物为前躯体,采用爆炸法合成石墨烯。利用XRD,SEM,XPS,TEM,SAED和Raman等测试手段对石墨烯的形貌,成份和结构进行表征。结果表明,石墨氧化物在爆炸产生的热量和冲击波的作用下发生完全剥离并被还原成石墨烯。新合成的石墨烯呈... 详细信息

以石墨氧化物为前躯体,采用爆炸法合成石墨烯。利用XRD,SEM,XPS,TEM,SAED和Raman等测试手段对石墨烯的形貌,成份和结构进行表征。结果表明,石墨氧化物在爆炸产生的热量和冲击波的作用下发生完全剥离并被还原成石墨烯。新合成的石墨烯呈透明褶皱状,含有2层～5层石墨层,并具有较好的晶体结构。

关键词：石墨烯石墨氧化物爆炸剥离

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商贸流通服务业影响力政策分析

中国流通经济 2008年第4期22卷 11-14页

作者：中国社会科学院课题组宋则中国社会科学院北京市100836 中国社会科学院财贸经济研究所

重新认识和充分发挥商贸流通服务业的影响力已成为新世纪国内外关注的重大前沿问题,更是践行科学发展观、转变发展方式、落实中央一系列战略意图的全局性问题。商贸流通服务业影响力是商贸流通服务业直接贡献和间接贡献(外溢效应或外部... 详细信息

重新认识和充分发挥商贸流通服务业的影响力已成为新世纪国内外关注的重大前沿问题,更是践行科学发展观、转变发展方式、落实中央一系列战略意图的全局性问题。商贸流通服务业影响力是商贸流通服务业直接贡献和间接贡献(外溢效应或外部性)的总称。以往商贸流通服务业影响力被低估,与忽视其溢出效应有直接关系。商贸流通服务业的外溢效应对于提高国民经济运行质量、优化国民经济流程、调整国民经济结构、扩大国内需求、增进社会总福利等全局性的潜移默化的影响能力,可能远远大于它所提供的直接贡献,低估这种外溢效应是长期以"来重生产、轻流通"的真正原因之一。

关键词：商贸流通服务业影响力实证溢出效应

EFFECT OF PARAMETERS ON DENDRITIC PATTERNS AND MICROSEGREGATION OF Ni-Cu BINARY ALLOY

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EFFECT OF PARAMETERS ON DENDRITIC PATTERNS AND MICROSEGREGAT...

负载钛催化丁二烯-异戊二烯共聚合反应动力学的研究

第五届国际材料与热加工物理模拟及数值模拟学术会议

作者： Changsheng ZHU1,2, Li FENG1, Zhiping WANG1,Rongzhen XIAO1 1 State Key laboratory of Gansu advanced Non-ferrous Metal Materials, Lanzhou University of Technology Lanzhou, 73.050, china 2 CAD Center, Lanzhou University of Technology Lanzhou, 73.050, china

The effects of various material parameters such as solid diffusivity Ds, anisotropy parameterε , interface kinetic coefficient β and surface energy σ on dendritic patterns and microsegregation is investigated by using a phase-field model which couples concentration gradient for two-dimensional simulation of binary alloy solidification. The computed results indicate that, different material parameters lead to different dendritic patterns and severity of microsegregation. The smaller Ds is, as well as the larger ε, β, σ are, the greater the dendritic tip velocity is, the more developed the side-branches are. The larger Ds is, the less drastically the solid’s solute composition undulates, and the extent of microsegregation minishes;ε affects the dendritic tip’s steady state, the larger εis, the more drastically the solid solute composition’s undulation is, and the severity of microsegregation ahead of solid/liquid interface aggravates;the larger β is, the more acutely the solid solute composition’s fluctuates, but the severity of microsegregation ahead of solid/liquid interface reduces;On increasing σ , the fluctuant extent of the solid’s solute composition reduces correspondingly, and an increased level of σ alleviates the severity of microsegregation ahead of solid/liquid interface.

关键词： Phase-field model Dendritic patterns Microsegregation Numerical simulation

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弹性体 2002年第1期12卷 1-6页

作者：贺爱华姚薇黄光兴黄宝琛焦书科胡友良中国科学院化学研究所分子科学中心工程塑料国家重点实验室北京100080 青岛化工学院高分子材料科学与工程系山东青岛266042 北京化工大学材料科学与工程学院北京100029

研究了TiCl4 /MgCl2 负载型高效催化剂催化丁二烯 -异戊二烯共聚合的动力学特征 ,并对影响聚合速率的因素进行了考察。首先通过计算排除了扩散控制对反应总聚合速率的影响 ,测定了单体浓度和催化剂浓度的反应级数和表观活化能 (2 2 .8kJ... 详细信息

研究了TiCl4 /MgCl2 负载型高效催化剂催化丁二烯 -异戊二烯共聚合的动力学特征 ,并对影响聚合速率的因素进行了考察。首先通过计算排除了扩散控制对反应总聚合速率的影响 ,测定了单体浓度和催化剂浓度的反应级数和表观活化能 (2 2 .8kJ/mol) ,建立的聚合速率方程为 :R =kp·f·[Ti]·[M]。

关键词：催化反应动力学研究丁二烯异戊二烯负载钛共聚合

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北京郊区小麦光能利用率的初步探讨

Journal of Integrative Plant Biology 1975年第1期 25-34页

作者： PHOTOENERGT UTILIZATION RESEARCH GROUP,laboratory OF AGROMETEOROLOGY,PEKING academy OF AGRICULTURE 北京市农业科学院农业气象研究室光能利用研究组

本文分析了北京地区小麦生长期内太阳总辐射特征,以及许家务、塔院大队小麦不同群体结构光能利用状况。小麦亩产800—1000斤经济产量光能利用率在0.4—0.5％间,生物学产量光能利用率在1.17—1.89％左右。生长盛期最高光能利用率可达5.09... 详细信息

本文分析了北京地区小麦生长期内太阳总辐射特征,以及许家务、塔院大队小麦不同群体结构光能利用状况。小麦亩产800—1000斤经济产量光能利用率在0.4—0.5％间,生物学产量光能利用率在1.17—1.89％左右。生长盛期最高光能利用率可达5.09％,说明北京地区先进社队小麦生产已具有相当水平。但从光能利用观点看,继续增产还有很大潜力。在分析小麦光合生产率、光合势、光能利用率与产量关系的基础上,提出了北京地区小麦适宜群体结构及提高光能利用率的增产途径。

关键词：光能利用率初步探讨经济产量小麦麦类作物光合势光合生产率净同化率生物指标总辐射量北京郊区

Characterization of a Strain Capable of Degrading a Herbicide Mixture of Quinclorac and Bensulfuronmethyl

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Pedosphere 2008年第5期18卷 554-563页

作者： Lǖ Zhen-Mei LI Zi-Mu SANG Li-Ya MIN Hang College of Life sciences Zhejiang University Hangzhou 310058 （China）

A bacterial strain,designated as LS,was isolated from a contaminated soil and was found to be capable of utilizing quinclorac,bensulfuronmethyl,and a mixture of the two as carbon and energy sources for growth. Strain LS was identified as Ochrobactrum sp. based on its physiological-biochemical properties,16S rDNA sequences,and phylogenetic analysis. The extent of degradation of quinclorac and bensulfuronmethyl at initial concentrations of 1.5 and 0.1 g L-1 was 90% and 67%,respectively,as measured by high performance liquid chromatography(HPLC) . When a herbicide mixture of 0.3. g L-1 quinclorac and 0.02 g L-1 bensulfuronmethyl was applied as carbon sources,quinclorac and bensulfuronmethyl were degraded at 95.7% and 67.5%,respectively. It appears that quinclorac is utilized more easily in a mixture than in a single state. The optimal temperature for growth of strain LS was 3. ℃. Strain LS grew well at pH 6 to 9 and had the highest degradation level for quinclorac and bensulfuronmethyl at an initial pH of 7 and 8,respectively. Addition of 0.25 g L-1 yeast extract could promote the growth and extent of degradation of quinclorac and bensulfuronmethyl by strain LS. Strain LS also showed the capability to degrade other aromatic compounds such as catechol,propisochlor,4-chloro-2-methylphenoxyacetic acid sodium(MCPA-Na) and imazethapy. The isolate LS shows a huge potential to be used in bioremediation for treating complex herbicide residues.

关键词： bensulfuronmethyl degradation herbicide mixture Ochrobactrum sp. quinclorac

Optical and acoustic phonon modes confined in gallium phosphide nanoparticles

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Rare Metals 2010年第6期29卷 561-566页

作者： ZHANG Zhaochun and ZHANG Neng School of Material Science and Engineering,Shanghai University,Shanghai 200072,china School of Material Science and Engineering Shanghai University Shanghai China

The main aim of this paper is to discuss the confinement effects on the optical and acoustic phonon vibrational modes in gallium phosphide（GaP） nanoparticles（cylindric grain）.The Raman scattering from the GaP nanoparticles was *** was found that the red-shifts of the longitudinal optical（LO） mode and transverse optical（TO） mode were 15 cm？1 and 13.8 cm？1,*** is generally accepted that the red-shifts of the optical phonon modes are due to the presence of smaller nanosized particles（～1.2 nm） acting as the nanoclustered building blocks of the GaP *** the low frequency Raman spectrum,a set of Stokes lines with almost the same spacing was clearly *** scattering feature originates from the discrete phonon density of states of the nanoclustered building *** to Lamb＇s vibrational theory,the Raman shift wavenumbers of the spheroidal mode and torsional mode of the lowest energy surface modes for the nanoclustered building blocks were *** agreement can be achieved between the calculated results and the observed scattering *** results indicate that the corresponding Raman peaks are due to scattering from the localized acoustic phonons in the nanoclustered building blocks in the GaP nanoparticles.

关键词： spectroscopy phonon mode Raman scattering gallium phosphide nanoparticles confinement effects

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多组件协作式网络安全系统的分析与设计

计算机工程与应用 2002年第23期38卷 172-175页

作者：蒋文保王常吉杨大鉴任晓明中国科学院高能物理研究所计算中心北京100039 中国科学院研究生院信息安全国家重点实验室北京100039 深圳市金海威新科技开发有限公司北京分公司北京100088

该文提出了一种集网络安全评估分析、防护、检测和响应技术为一体的多组件动态协作式网络安全系统。该系统采用多组件动态协作模型设计,主要包括防火墙、网络探测器、主机代理、扫描器、管理控制台等多种安全组件,系统中各个组件之间能... 详细信息

该文提出了一种集网络安全评估分析、防护、检测和响应技术为一体的多组件动态协作式网络安全系统。该系统采用多组件动态协作模型设计,主要包括防火墙、网络探测器、主机代理、扫描器、管理控制台等多种安全组件,系统中各个组件之间能动态地密切协作,共同维护网络安全。文中重点阐述了该系统的结构、多组件协作的具体内容及其实现,以及用于支持协作的基于PKI的身份认证及保密通信机制。

关键词：多组件协作式网络安全系统分析设计防火墙扫描器入侵检测计算机网络