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Science china Chemistry 2009年第9期52卷 1417-1422页

作者： LOU LanLan1, YU Yi1, YU Kai2, JIANG Shu1, DONG YanLing1 & LIU ShuangXi1 1 institute of New Catalytic Materials Science, College of Chemistry, Nankai University, tianjin 3.0071, china 2 College of Environmental Science and Engineering, Nankai University, tianjin 3.0071, china institute of New Catalytic Materials Science College of Chemistry Nankai University Tianjin China College of Environmental Science and Engineering Nankai University Tianjin China

An imidazole modified mesoporous material has been prepared through a co-condensation procedure and adopted to covalently anchor chiral Mn(Ⅲ) salen complex. The active centers in the as-synthesized catalyst were presented in the form of ionic species. The results of XRD, FTIR, DRUV-Vis, and N2 sorp-tion confirmed the successful immobilization of chiral Mn(Ⅲ) salen complex inside the channels of the modified support and the maintenance of the mesoporous structure of parent support in the immobi-lized catalyst. This heterogeneous catalyst exhibited comparable catalytic activity and enantioselectiv-ity to those of the homogeneous counterpart in the asymmetric epoxidation of unfunctionalized olefins. Furthermore, notably high turnover frequencies have been obtained over this heterogeneous catalyst for the relatively short reaction time and low catalyst amount, due in part to the ionic property as well as the uniform distribution of the active centers.

关键词： imidazole-functionalized mesoporous material chiral Mn(Ⅲ) salen complex co-condensation asymmetric epoxidation unfunctionalized olefins

Study on the Interaction of Water Waves with Semi-Circular Breakwater

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china Ocean Engineering 1999年第1期14卷 73-80页

作者： JIA Donghua Engineer, The First Design institute of Navigation Engineering, Ministry of Communications of china, tianjin 3.0222, P. R. china. First Design institute of Navigation Engineering Ministry of Communications of China Tianjin 300222 China

The present study investigates the interaction of steep waves with semi-circular breakwater with the complex plane's Cauchy boundary integral theorem. The boundary integral method is used to transform the calculation in fluid domain into its boundary alone. In the calculation the computation domain is moved with the propagation of waves. A numerical solution is obtained for incident Stokes waves passing the submerged obstacles. This method has been extended to the calculation of wave run-up on a slope for estimating wave overtopping.

关键词： semi-circular breakwater water waves interaction Cauchy boundary integral

APPROXIMATE SUBDIFFERENTIALS AND NONSMOOTH ANALYSIS FINITE DIMENSIONS

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Systems Science and Mathematical Sciences 1992年第1期5卷 84-96页

作者： WANG Yuntong (Nankai institute of Mathematics,tianjin 3.0071,china) 南开大学天津

Ioffe’s approximate subdifferentials are reviewed and some of his resultsare *** extension of the calculus of the approximate subdifferentials forthe sums to any finite number of functions is provided along with a generalizationof the Dubovitzkii-Milyutin *** presentation also indicates some of thelimitations of nonsmooth analysis and *** to the class offunction which is suitable for most of the purposes in nonsmooth optimization issuggested.

关键词： Approximate subdifferentials Dini subdifferential Clarke generalized gradient contingent cone Clarke tangent cone normal cone regular function strong general position property subdifferential calculus

Design of Metal-clad Ti: LiNbO3.Polarizer

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Chinese Journal of Lasers 1996年第5期B5卷 444-450页

作者： HU H. Z., CHENG G.(Department of applied Pysics, tianjin University, tianjin 3.0072, china)GEN F SONG Q., LI C. F., ZHAO C.(The 83.8 {3. of CASC, tianjin 3.0192, china) tianjin Univ Tianjin China

ＤｅｓｉｇｎｏｆＭｅｔａｌ－ｃｌａｄＴｉ：ＬｉＮｂＯ＿３ＰｏｌａｒｉｚｅｒＨＵＨ．Ｚ．，ＣＨＥＮＧＧ．（ＤｅｐａｒｔｍｅｎｔｏｆａｐｐｌｉｅｄＰｙｓｉｃｓ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙ，Ｔｉａｎｊｉｎ３０００７... 详细信息

ＤｅｓｉｇｎｏｆＭｅｔａｌ－ｃｌａｄＴｉ：ＬｉＮｂＯ＿３ＰｏｌａｒｉｚｅｒＨＵＨ．Ｚ．，ＣＨＥＮＧＧ．（ＤｅｐａｒｔｍｅｎｔｏｆａｐｐｌｉｅｄＰｙｓｉｃｓ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙ，Ｔｉａｎｊｉｎ３０００７２，Ｃｈｉｎａ）ＧＥＮＦ；ＳＯＮＧ...

关键词： integrated optics polarizer UNbO3.waveguide

Study on the Performance of the nonlinear Joint Transform Correlator

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Chinese Journal of Lasers 1997年第2期B6卷 122-130页

作者： QIN Yuwen GE BaozhenCHEN Ximing ZHANG Yimol JIAN Shuisheng(institute of Lightwave Technology,Northern Jiaotong University, Beijing 100044)(institute of Optoelectronic and Precision Engineering , tianjin University, tianjin 3.0072 china) Northern Jiaotong Univ Beijing China

We present the nonlinear joint transform correlation computer simulation results and the optical experimental results of the scale and rotation varying objects, as well as the statistical experimental results of the autocorrelation peak distribution of the object. The given experimental results show clearly that the optical experimental system is a nonlinear joint transform correlation system and the distribution of the autocorrelation peak is to some extent random. Correlation peak signal intensity of the nonlinear joint transform correlation system has no obvious variation when the scale variation of the object is less than 10% or the rotation angle variation of the object is less than 5 degrees.

关键词： optical pattern recognition real-time joint transform correlation nonlinear joint transform correlation

A Method of Problem Situation Decomposing to Support Goal Finding

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Systems Science and Systems Engineering 1996年第3期6卷 349-355页

作者： DING Ronggui HAN Wenxiu(institute of Systems Engineering, tianjin University tianjin, 3.0072, {3.)

DSS have been taken as hopfull supports tools for decision making for more than 20 years. There are a lot of literatures on DSS, but unfortunately most of them are not so practical as the designers expected. This paper points out the crux of this situation and argues that the research on DSS should pay some more attention to the decision making activities before the model using stage. A method named "Problem Situation Decomposing Graph (PSDG)" is presented in this paper for helping the decision maker (DM) elicite the problem systems. A PSDG is an acycle AND/OR logical directed graph, which includes all the factors, based on the DM’s knowledge, affecting the problem situation. The logical relationship and utility determining methods in a PSDG can reflect the DM’s decision making style. A method named "Critical Factor Method (CFM)" aided by a logical graph searching algorithm is used to analysis and derive the critical factors which the DM should take into account with priority, and thus supports him to find the decision making goals half artificially and half automatically.

关键词： Dss graph decision making problem goal.

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气测录井中真空蒸馏脱气自动控制系统的研究

石油学报 2004年第3期25卷 110-114页

作者：何宏靳世久郝庭柱薛京生李莺莺天津大学精密测试技术及仪器国家重点实验室天津理工学院光电信息与电子工程系天津3.0191 天津理工学院光电信息与电子工程系天津大学电子信息工程学院

气测录井是综合录井过程中发现和评价油气层的重要手段。针对我国气测录井的特点 ,提出了一种自动真空蒸馏脱气的新方法 (简称AVMS) ,实现了样品气真正意义上的无基础性失真 ,克服了使用传统常规脱气方法中样品气不受控制而混入空气 ,... 详细信息

气测录井是综合录井过程中发现和评价油气层的重要手段。针对我国气测录井的特点 ,提出了一种自动真空蒸馏脱气的新方法 (简称AVMS) ,实现了样品气真正意义上的无基础性失真 ,克服了使用传统常规脱气方法中样品气不受控制而混入空气 ,造成基础性失真的缺陷。给出了系统设计的理论依据 ,AVMS的工作原理、气路流程及特点 ,实验证明 ,该系统提供的样品气总烃含量比常规脱气器脱出的气体含量高出 10倍以上。

关键词：气测井含气饱和度烃类检测全烃气体浓度自动控制系统

PALYNOLOGICAL ASSEMBLAGES FROM THE ZHIDAN GROUP OF HUATING AND LONGXIAN REGION,SOUTHWESTERN PART OF ORDOS BASIN

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西北地质科学 1989年第25期 79-96页

作者： Zhang Zifu (Xi’an institute of Geology and mineral resources,CAGS)Miao Shujuan ({3. institute of Geology and mineral resources,CAGS)

The working area is distributed from the Huating County of Gansu Pro-vince to Longxian County of Shaanxi Province in the southwestern Ordos Ba-sin. The Zhidan Group in this area, a series of terrestrial sediments, may be subdivided into five formations as follows(from lower to upper): Yijun-Luohe,Huanhe-Huachi, Luohandong, Jingchuan and Fengshan Formations. All samples were coliected from 1

关键词：未定种图版 PALYNOLOGICAL ASSEMBLAGES FROM THE ZHIDAN GROUP OF HUATING AND LONGXIAN REGION,SOUTHWESTERN PART OF ORDOS BASIN 希指相似种近似种单沟鄂尔多斯盆地西南部罗汉松罗汉杉罗汉松属陇县地区西安地质矿产研究所金毛狗

The isometric extension of “into” mappings on unit spheres of AL-spaces

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Science china Mathematics 2008年第10期51卷 1904-1918页

作者： DING GuangGui School of Mathematics Science, Chern institute of Mathematics and LPMC, Nankai University, tianjin 3.0071, china School of Mathematics Science Chern Institute of Mathematics and LPMC Nankai University Tianjin 300071 China

In this paper, we show that if V0 is an isometric mapping from the unit sphere of an AL-space onto the unit sphere of a Banach space E, then V0 can be extended to a linear isometry defined on the whole space.

关键词： isometric extension (atomic) AL-space

Trihalomethanes adsorption on activated carbon fiber

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Journal of Environmental Sciences 1996年第2期8卷 167-172页

作者： Li Junwen Yu Zuobin Gao Ming Cai Xinpei Chao Fuhuan (institute of Hygiene and Environmental Medicine, tianjin 3.0050, china) Inst. of Hyg./Environmental Medicine Tianjin 300050 China

The mechanism of activated carbon fiber (ACF) adsorption trihalomethanes (THMs) was studied. It was found that ACF adsorption THMs was exothermic, the physico-adsorption principally, but not a complete monolayer adsorption. The adsorptive capacities of ACF increased as the four species of THMs became more hydrophobic, and as the chlorine atoms in CHCls were substituted by more bromine atoms. The result of fixed-bed reactor adsorption was fitted to that of isotherm experiments.

关键词： trihalomethanes adsorption ACF.