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Microstructure,Properties and Heat Treatment Process of Powder Metallurgy Superalloy FGH95

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Journal of Iron and Steel Research International 2006年第5期13卷 65-68页

作者： GUO Wei-min wu jian-tao ZHANG feng-ge ZHAO Ming-han High Temperature Materials Research Institute Central Iron and Steel Research Institute Beijing 100081 China

Microstructure and properties of nickel based powder metallurgy （PM） superalloy were presented. Effects of nonmetallic inclusions and heat treatment on microstructure and properties were. discussed. Development tend... 详细信息

关键词： microstructure property PM superalloy heat treatment

Dioxyxanthones from Polygala hongkongensis and Their Cytotoxicity

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Chemical Research in Chinese Universities 2011年第5期27卷 777-779页

作者： wu jian-feng TU Peng-fei ZHAN Hai-tao GAO Jing-chun College of Medicine Foshan University Foshan 528000 P. R. China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Health Science Center Beijing 100191 P. R. China Department of Biology and Chemistry City University of Hongkong Hong Kong SPR P. R. China

Two new dioxyxanthones, polyhongkongenoxanthones A and B（1 and 2） were isolated from the herbs of Polygala hongkongensis, together with six known xanthones. Their structures were elucidated on the basis of chemical and spectroscopic evidence. The isolates were tested for their cytotoxicity against three tumor cell lines（HepG2, GLC-82 and MCF-7, HepG2=human hepatocellular carcinoma cells; GLC-82=human lung carcinoma cells; MCF-7= human breast carcinoma cells） by MTT assay, among which polyhongkongenoxanthone B（2）, 1,7-dihydroxy-2,3- methylenedioxyxanthone（3） and 1,7-dihydroxy-3,4,8-trimethoxyxanthone（6） are potential antitumor candidate due to their significant cytotoxic effects on the three cell lines..

关键词： Polygala hongkongensis Polygalaceae Dioxyxanthone Polyhongkongenoxanthone A and B Cytotoxicity

Megastigmane Glycosides from Polygala hongkongensis Hemsl

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Chemical Research in Chinese Universities 2007年第5期23卷 530-532页

作者： wu jian-feng CHEN Si-bao GAO Jing-chun wu Li-jun CHEN Shi-lin TU Peng-fei School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 P. R. China School of Pharmaceutical Sciences Peking University Health Science Center Beijing 100083 P. R. China State Key Laboratory of Chinese Medicine and Molecular Pharmacology Department of Applied Biology and Chemical Technology College of Medicine Foshan University Foshan 528000 P. R. China Institute of Medicinal Plant Development Chinese Academy of Medical Science Peking Union Medical College Beijing 100094 P. R. China

Two new megastigmane glycosides,7Z-roseoside,and 7Z-trifostigmanoside Ⅰ,as well as,four known compounds,trifostigmanoside Ⅱ,epimedin C,3＇,7-dihydroxy-4＇-methoxyisoflavone-7-D-glucopyranoside,and formenonetin,were isolated from Polygala hongkongensis *** structures of the isolated compounds were established on the basis of UV,IR,NMR,and MS spectral *** glycosides（1-3）were isolated from the family Polygalaceae for the first time.

关键词： Poiygala hongkongensis Polygalaceae Megastigmane glycosides 7Z-Roseoside 7Z-Trifostigmanoside I

Vapor-liquid equilibria of CH_4, CO_2 and their binary system CH_4 + CO_2: A comparison between the molecular simulation and equation of state

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Science China(Technological Sciences) 2015年第4期58卷 650-658页

作者： YANG Zhi GONG Mao Qiong ZHOU Yuan DONG Xue Qiang LI Xiao Dong LI Hui Ya wu jian feng Key Laboratory of Cryogenics Technical Institute of Physics and Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences School of Energy and Power Engineering Beihang University

An accurate knowledge about phase behaviors of CH4, CO2 and their binary mixture is crucial in fields of natural gas liquefaction and refrigeration applications. In this work, two all-atom force fields of TraPPE-EH and EMP2 were used for the components CH4 and CO〉 respectively. Then the vapor-liquid equilibria （VLE） of CH4, CO2 and their binary system were calculated via the NVT- and NpT Gibbs Ensemble Monte Carlo Simulations. Meanwhile the traditional method using Equation of State （EoS） to correlate the VLE properties was also investigated. The EoSs considered in this work were three classic cubic RK, SRK, PR and another advanced molecular-based PC-SAFT equations. For pure components, both molecular simulations and the PC-SAFT EoS could obtain satisfactory predictions for all the saturated properties. However, the saturated liquid densities calculated by the cubic EoSs were not so good. It was also observed that the TraPPE-EH force field had a good representation for CH4 molecule, while the EMP2 force field was not enough accurate to represent CO2 molecules. For the mixture CH4 ＋ CO2, SRK and PR showed the best predictions for the saturated pressure-component property, while good results were also obtained via molecular simulations and PC-SAFT EoS. It was suggested that special combining rules or binary interaction parameters were important to obtain enough accurate prediction of the mixed phase behavior. Compared with the cubic EoS, the PC-SAFT and molecular simulation method showed better adaptabilities for both the pure and mixture systems. Besides, the accurate molecular parameters used in the PC-SAFT and molecular simulations could bring about direct and deep understanding about the molecular characteristics.

关键词： molecular simulation equation of state CH4 CO2 vapor-liquid equilibrium

A BRIEF INTRODUCTION TO MERIDIAN PROJECT

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空间科学学报 2002年第Z1期22卷 35-38页

作者： WEI fengsi XIAO Zuo wu jian GUO jianshan feng Xueshang Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Department of Geophysics Peking University P.R. China Institute of Radio Propagation Ministry of Information Industry P.R.China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China Center for Space Science and Applied Research The Chinese Academy of Sciences Beijing 100080 P.R. China

　　Early in 1994, sponsored by Chinese Academy of Sciences (CAS) and then the State Science and Technology Commission of China (SSTC, now Ministry of Sci ence and Technology), Chinese space scientists (including scientists from Taiwan) gathered together to discuss issues on the development of space physics researches in China. Following it, several special seminars were held to continue the discus sion which finally led to a proposal to CAS and SSTC for establishing a station chain along the 120°E to monitor the space environment. This proposal was care fully reviewed and thoroughly evaluated by many leading scientists in the com munity and then listed in the State Plan of Chinese Central Government in June 1997. The project then has been formally called as "Meridian Chain of Compre hensive Ground-Based Space Environment Monitors in the Eastern Hemisphere" "Meridian Project". After several years of preparations the project has been par tially initiated with the efforts devoted by institutes and universities involved.……

关键词： space environment Science and Technology

Synthesis and Microstructure of Doped Alumina Composite Membrane by Sol-Gel Process

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Journal of wuhan University of Technology(Materials Science) 2003年第3期18卷 15-19页

作者：徐晓虹 School of Materials Science and Engineering Wuhan University of Technology

The supported membranes of Al 2O 3 and its modification membranes were *** 2O 3,Al 2O 3 SiO 2 TiO 2 and Al 2O 3 SiO 2 TiO 2 ZrO 2 membranes were mamufatured by the slip casting process using mixing boehmite,silicate,titania and zirconia sols under proper conditions,then the composite membrane was *** structure and characteristics of the membrane were determined by XRD,SEM and AFM *** conditions of preparation of the membrane are *** thickness of the layer is about 1-2μm,the diameter of an average pore is 200-300nm and has a narrow pore distribution without crack *** changing the ratios of Al∶Si∶Ti∶Zr(mol),variations of surface pore size of Al 2O 3 SiO 2 TiO 2 ZrO 2 membrane can be gained.

关键词： doped alumina composite membrane sol gel process

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不同开挖深度下基坑桩——撑式支护结构研究

铁道工程学报 2013年第10期30卷 26-30页

作者：吴剑锋铁道第三勘察设计院集团有限公司天津300142

研究目的:随着开挖深度不同的基坑工程越来越多,其围护结构的位移和内力的计算也更加复杂。本文运用有限元程序ANSYS建立分析模型,研究不同开挖深度下支护结构的变形及内力,为深基坑支护结构设计提供重要依据。研究结论:(1)围护结构侧... 详细信息

研究目的:随着开挖深度不同的基坑工程越来越多,其围护结构的位移和内力的计算也更加复杂。本文运用有限元程序ANSYS建立分析模型,研究不同开挖深度下支护结构的变形及内力,为深基坑支护结构设计提供重要依据。研究结论:(1)围护结构侧向位移、弯矩随着基坑的开挖而变化,侧向位移、桩身弯矩的最大值一般发生在基坑的开挖面附近;(2)在不同挖深情况下,基坑两侧围护结构的位移、内力都存在差异,在设计时需要分别考虑结构参数;(3)本文对不同挖深基坑支护结构的设计有一定的参考意义。

关键词： ANSYS 基坑开挖深度位移内力

Numerical modeling of water yield of mine in Yangzhuang Iron Mine, Anhui Province of China

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Journal of Groundwater Science and Engineering 2015年第4期3卷 352-362页

作者： YANG Yun wu jian-feng LIU De-peng School of Earth Sciences and Engineering Hohai University Key Laboratory of Surficial Geochemistry Ministry of EducationDepartment of HydrosciencesSchool of Earth Sciences and EngineeringNanjing University East China Geological Exploration Bureau of Nonferrous Metals Jiangsu Province

This study develops a three-dimensional heterogeneous numerical model to simulate the water inrush process and predict the water yield for mineral exploration in Yangzhuang Iron Mine in Anhui Province. To identify the hydrogeological parameters of the aquifer in the study area, the model was calibrated and validated using the observed heads through the integrated trial-and-error and automated techniques. Also, the sensitivity analysis of the model was performed to evaluate the uncertainty associated with the calibrated model. According to the mine construction plan at different mining levels of-500 m,-600 m, and-700 m, the calibrated model was then applied to predict the water yields dependent on the different mining levels. As indicated by the prediction results, the numerical simulation model can systematically describe the groundwater system in the mining area and determine the source of water inrush in this iron mine. In conclusion, numerical analyses carried out in this study can provide guidance to decision-makers in balancing the iron ore mining and mine dewatering in the future.

关键词： Fracture-karst aquifer Numerical simulation Sensitivity analysis Water yield of mine Mine dewatering Yangzhuang Iron Mine

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基于反馈神经网络的动态化工过程建模

计算机与应用化学 2001年第2期18卷 105-110页

作者： wu jian-feng 吴建锋何小荣陈丙珍 Department of Chemical Engineering Tsinghua University北京100084

针对非线性动态化工过程建模存在的问题 ,提出了一种新的反馈神经网络结构 ,并将状态反馈、时间序列延迟以及集中节点的概念结合起来 ,用于提高反馈神经网络的性能 ,同时又使得网络结构不至于太复杂。在用此网络结构建模的时候 ,成功地... 详细信息

针对非线性动态化工过程建模存在的问题 ,提出了一种新的反馈神经网络结构 ,并将状态反馈、时间序列延迟以及集中节点的概念结合起来 ,用于提高反馈神经网络的性能 ,同时又使得网络结构不至于太复杂。在用此网络结构建模的时候 ,成功地将BP算法用于网络模型的训练。文中将这种反馈神经网络结构分别对一个单输入单输出 (SISO)的非线性动态系统和一个多输入单输出 (SIMO)的连续全混釜 (CSTR)模型进行建模 ,并将所得模型与基于静态BP神经网络所得的模型在模型输出精度和抗干扰性等方面进行了比较 ,证明了该反馈神经网络在动态过程建模中能够比静态BP模型更好地反映出动态过程的输入输出关系 ,并具有一定的抗干扰能力。

关键词：反馈神经网络集中节点非线性动态化工过程系统建模