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Product distributions of Fischer-Tropsch synthesis over Co/AC catalyst

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Journal of Natural Gas Chemistry 2011年第4期20卷 389-396页

作者： Weixin Qian Haitao Zhang Weiyong Ying Dingye Fang Engineering Research Center of Large Scale Reactor Engineering and Technology Ministry of EducationState Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China

The product distributions of Fischer-Tropsch synthesis over Co/AC catalyst are investigated under different reaction conditions in an integral fixed bed *** is found that the product distributions deviate from the ASF *** deviation from ASF distribution is analyzed by taking the readsorption of alkenes and the following secondary reaction into *** is noted that the contents of alcohol,alkene and alkane decline with the increasing carbon number,showing a slighter declining tendency of alkanes than those of alkenes and *** is also found that high temperature,space velocity,H2/CO in feed gas and low pressure are preferential for light hydrocarbons and alcohols while against the chain *** effect of space velocity on the product distributions especially on the light products is not *** is noticed that low temperature,space velocity,H2/CO and high pressure lead to high contents of alcohols;high temperature,H2/CO and low space velocity lead to high contents of *** effect of pressure on the amounts of alkanes is not significant;high space velocity and low temperature,pressure,H2/CO are preferential for alkenes.

关键词： Fischer-Tropsch synthesis product distribution Co/AC catalyst

2500 km-10 Gbps RZ transmission system based on dispersion compensation CFBGs without electric regenerator

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Frontiers of Optoelectronics 2008年第Z2期1卷 219-222页

作者： Jihong CAO Yong CHEN Ting CHEN Shuisheng JIAN Key Lab of All Optical Network and Advanced Telecommunication Network of EMC Beijing Jiaotong University Institute of Lightwave Technology Beijing Jiaotong University

The characteristics of chirped fiber Bragg gratings（CFBGs） are optimized so that the ripple coefficient of the power reflectivity spectrum and group time delay are less than 1 dB and |± 15| ps, group delay is about 2600 ps/nm, polarization module dispersion is very small, PMD < 2 ps,-3 dB bandwidth is about0.35 nm, and insertion loss is about 4–5 d Bm. Using dispersion compensation CFBG, a 2500 km-10 Gbps RZ optical signal transmission system on G.652 fiber was successfully demonstrated without an electric regenerator by optimizing dispersion management and loss management. The RZ optical signal was generated through a two-stage modulation method. At 2081 km, the power penalty of transmission is about 3 dB(conditions: RZ signal, BER = 10-12, PRBS = 1023-1); At 2560 km, the power penalty is about 5 dB. It is superior to the system using NRZ under the same conditions.

关键词： return to zero (RZ) signal chirped fiber Bragg grating (CFBG) dispersion compensation power penalty

Effects of slope position and land use on the stability of aggregateassociated organic carbon in calcareous soils

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Acta Geochimica 2017年第3期36卷 456-461页

作者： Man Liu Guilin Han Zichuan Li Taoze Liu Xiaomin Yang Yuntao Wu Zhaoliang Song School of Water Resources and Environment China University of Geosciences (Beijing) Institute of the Surface-Earth System Science Tianjin University The State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences

Topography and land use affect soil organic carbon(SOC) storage, stabilization, and turnover, through several biogeochemical processes. This study investigated the aggregate composition and SOC content of bulk soils and aggregates at different slope positions under different land uses in a typical karst catchment of southwestern China. Our results show that the proportion of macro-aggregates and the SOC content of bulk soils and aggregates at different slope positions decreased from the upper to the lower slope. The SOC content generally increased with an increase in the mean weight diameter and proportion of macro-aggregates under different land uses. Our results indicate that macro-aggregates in forest and grassland soils make a greater contribution to both aggregate composition and SOC content than that in arable land soils. Therefore,converting farmland to forest or grassland can facilitate the accumulation of macro-aggregates as well as the storage of SOC.

关键词： Soil organic carbon Aggregate fraction Land use Slope position Karst Southwest China

Construction of expression vectors and study on single-chain antibody and reshaping single-domain antibody against CD3

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Science China(Life Sciences) 1997年第3期40卷 270-276页

作者：刘喜富萧飒顾征王勇张卫国陈艾林晴黄华梁孙健陈润生沈倍奋陈兴 Institute of Genetics Chinese Academy of Sciences Beijing 100101 China Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Institute of Basic Medicine Academy of Military Medicine Sciences Beijing 100850 China

Two vectors, pWA180 and pROH80, for expression of single-chain Fv fragments (ScFv) were con-siruciea. (?)ne anti-CD3 VH and VL genes were amplified from UCHTl cells by RT-PCR and sequenced. Both genes were cloned in pWA180 to express native ScFv and pROH80 for GST-ScFv fusion protein expression. The expression products were analysed by ELISA and Western blot. The combining site of OKT3 was modeled. Human [g LS1 and Nd were selected as acceptors of CDRs of OKT3 VL and VH to construct a reshaping antibody against CD3. By com-paring OKT3, LS1 and Nd with their own family sequences, some residues were changed and the reshaping VL and VH genes were designed. The full VH gene was assembled in three steps with eight chemically synthesized oligonu-cleotide fragments using overlapping PCR and sequenced. The VH gene was expressed as active protein in pCOMB3 and as inclusion bodies in pGEX-4T-l by ELISA and Western blot analysis.

关键词： expression vector single-chain Fv fragment (ScFv) molecular modeling reshaping antibody glutathione s-transferase (GST).

Development of the Data Processing and Analysis System Framework for ICF Experiments

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Plasma Science and Technology 2005年第3期7卷 2872-2874页

作者：杨冬虞孝麒张弛 Department of Modern Physics University of Science & Technology of China Hefei 230026China

An idea is presented about the development of a data processing and analysis system for ICF experiments, which is based on an object oriented framework. The design and preliminary implementation of the data processing and analysis framework based on the ROOT system have been completed. Software for unfolding soft X-ray spectra has been developed to test the functions of this framework.

关键词： initial confinement fusion data processing and analysis object oriented framework ROOT soft X-ray spectra

SELF-ORGANIZING ASSEMBLY MODELING BASED ON RELATIONAL CONSTRAINTS

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Chinese Journal of Mechanical Engineering 2000年第2期13卷 145-152页

作者： Tan Jianrong 浙江大学计算机辅助设计与图形学国家重点实验室浙江杭州抚顺石油学院辽宁抚顺

On the research of assembly modeling of mechanical products,current CAD systems can only support the design Process of component-to-assembly. It is difficult to realize the design process of assembly-to -*** theory of self-organizing assembly modeling based on relational constraints is proposed, which implements the product design of assembly-to-component commencing with conceptual design and supporting abstract design and step-nice refinement design.

关键词： Assembly modeling Assembly constraint Self-organizing assembly

Microstructural features and precipitation behavior of Ti,Nb and V microalloyed steel during isothermal processing

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Journal of Iron and Steel Research International 2019年第1期26卷 102-111页

作者： Qi Zhou Zhuang Li Zhan-shan Wei Di Wu Jin-yu Li Zhen-yao Shao School of Environment and Chenlical Engineering Shenyang Ligong UniversityShenyang 110159LiaoningChina College of Materials Science and Engineering Shenyang Aerospace UniversityShenyang 110136LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110004LiaoningChina

Thermal simulations of Ti,Nb and V microalloyed steel were conducled using a thermomechanical simulator,and the microstructural evolution and the precipitation behavior during isothermal processing were *** results show that with increasing holding time,the microstructural constituents change from the martensite and bainitic ferrites to granular bainite and polygonal *** maximum hardness is obtained for the specimen after isothermal holding for 5s due to the martensite strengthening *** hardness of the specimen decreases after isothermal holding for 10s,because the strengthening contribution of fine dispersed precipitates becomes *** hardness values of the specimens increase and then remain high after isothermal holding for 60 and *** is attributed to the contribution of the interphase precipitation hardening to the hardness of the studied *** precipitates in the specimen are coarsened after isothermal holding for 3600s,even though the coarsening is not *** precipitates are fee(***)(N.C)particles and belong to the MX-type *** beneficial effects of precipitation strengthening are *** hardness decreases to a minimum hardness value due to the presence of large amounts of polygonal ferrite after isothermal holding for *** coarse precipitates are the primary origin of the hardness decrease.

关键词： Microalloyed steel Isothermal holding time Microstructural constituent Precipitation Hardness

Lacunary Keggin Polyoxotungstate as Reaction-controlled Phase-transfer Catalyst for Catalytic Epoxidation of Olefins

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Chinese Journal of Chemistry 2004年第8期22卷 874-876页

作者：李明强蹇锡高杨永强 Department of Polymer Science & Materials Dalian University of Technology Dalian Liaoning 116012 China

A new reaction-controlled phase-transfer catalyst system, lacunary Keggin polyoxotungstate [C7H7N(CH3)3]9PW9O34 has been synthesized and used for catalytic epoxidation of olefins with H2O2 as the oxidant. Infrared spectra were used to analyze the behavior of the phase transfer of catalyst. In this system, the catalyst not only can act as homogeneous catalyst but also as heterogeneous catalyst to be easily filtered and reused. The epoxi- dation reaction is clean and exhibits high conversion and selectivity as well as excellent catalyst stability.

关键词： reaction-controlled phase-transfer catalyst olefins epoxidation

Electromechanical wave in power systems:theory and applications

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Journal of Modern Power Systems and Clean Energy 2014年第2期2卷 163-172页

作者： Yan XU Fushuan WEN Gerard LEDWICH Yusheng XUE School of Electrical Engineering Zhejiang UniversityHangzhou 310027China Queensland University of Technology Gardens PointBrisbaneQLDAustralia State Grid Electric Power Research Institute Nanjing 210003China

The continuum model is a key paradigm describing the behavior of electromechanical transients in power *** the past two decades,much research work has been done on applying the continuum model to analyze the electromechanical wave in power *** this work,the uniform and non-uniform continuum models are first briefly described,and some explanations borrowing concepts and tools from other fields are ***,the existing approaches of investigating the resulting wave equations are *** application named the zero reflection controller based on the idea of the wave equations is next presented.

关键词： Power system Electromechanical wave propagation Continuum model Zero reflection controller