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Laser glazing study of Co-based alloy and Ni-Nb-Cr alloy coating

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Chinese Journal of Lasers 1994年第4期B3卷 377-384页

作者： TIAN Nailiang(department of Applied Physics,tianjin Institute of Science and Technology, tianjin 300191,china)YANG Yongqiang(department of mechanics, tianjin Institute of Textile Science and Technology,tianjin 300160, china) tianjin Inst of Science and Technology Tianjin China

ＬａｓｅｒｇｌａｚｉｎｇｓｔｕｄｙｏｆＣｏ－ｂａｓｅｄａｌｌｏｙａｎｄＮｉ－Ｎｂ－Ｃｒａｌｌｏｙｃｏａｔｉｎｇ￥ＴＩＡＮＮａｉｌｉａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓ，ＴｉａｎｊｉｎＩｎｓｔｉ... 详细信息

ＬａｓｅｒｇｌａｚｉｎｇｓｔｕｄｙｏｆＣｏ－ｂａｓｅｄａｌｌｏｙａｎｄＮｉ－Ｎｂ－Ｃｒａｌｌｏｙｃｏａｔｉｎｇ￥ＴＩＡＮＮａｉｌｉａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓ，ＴｉａｎｊｉｎＩｎｓｔｉｔｕｔｅｏｆＳｃｉｅｎｃｅａｎｄＴ...

关键词： Metallic glass cladding layer Co-based

Preparation of two triflate precursors for O-(2.[^(18)F] fluoroethyl)-L-tyrosine used in positron emission tomography (PET)

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Science china Chemistry 2009年第12期52卷 2195-2199页

作者： LIU ChunYan1,2.& JIANG ShenDe1 1 School of Pharmaceutical Science and Technology,tianjin University,tianjin 300072.china 2.{2. of Pharmacy,North china Coal Medical College,Tangshan 063000,china 1. School of Pharmaceutical Science and Technology Tianjin University Tianjin 300072 China 2. department of Pharmacy North China Coal Medical College Tangshan 063000 China

Two novel triflate precursors for radiolabelling of L-tyrosine in positron emission tomography (PET) for tumor imaging,O-(2.trifluoromethanesulfonyloxyethyl)-N-(tert-butoxycarbonyl)-L-tyrosine methyl ester 9a and O-(2.trifluoromethanesulfonyloxyethyl)-N-(tert-butoxycarbonyl)-L-tyrosine tert-butyl ester 9b,are synthesized. The triflate agent,9a or 9b,is prepared by esterification of methanol or transesterification of tert-butyl acetate with L-tyrosine,protection of the amine group with di-tert-butyl dicarbonate,alkylation with chlorohydrin,and triflation with trifluoromethanesulfonic anhydride in four steps with overall yields of 30% and 15%,respectively.

关键词： positron emission tomography triflate L-tyrosine [18F]FET precursor PET imaging

Research progress of the NSFC Major Research Plan “Dynamic Disaster Evolution of Major Engineering Structures”

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Science china(Technological Sciences) 2010年第2期53卷 592-594页

作者： RU JiPing1, LI DaPeng1, LI ZhongXian2.1 department of Engineering & Materials Science, NSFC, Beijing 100085, {2. 2.School of Civil Engineering, tianjin University, tianjin 300072, {2. 1. department of Engineering & Materials Science NSFC Beijing 100085 China2. School of Civil Engineering Tianjin University Tianjin 300072 China

The NSFC Major Research Plan aims to conduct researches at the international research frontiers on modeling of strong earthquake ground motions and strong wind or typhoon fields, and investigating the damage and failure evolution process of the major engineering structures under dynamic actions, focusing on the following two key scientific problems: (1) characteristics and laws of strong earthquake ground motions and strong wind or typhoon fields, and (2. process and mechanism of dynamic disaster evolution of the major engineering structures. For these goals, the research work is targeted at (1) modeling and predicting of strong earthquake ground motion and strong wind or typhoon fields, (2. identifying critical parameters influencing the dynamic disaster evolution of the major engineering structures, (3) analyzing the whole dynamic disaster evolution process of the major engineering structures, and (4) integration and verification of simulation systems for dynamic disaster evolution of the major engineering structures.

关键词： major engineering structures dynamic disaster evolution research progress

STRONG CONVERGENCE OF MONOTONE HYBRID METHOD FOR FIXED POINT ITERATION PROCESSES

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Journal of Systems Science & Complexity 2008年第3期21卷 474-482页

作者： Yongfu su Xiaolong QIN department of Mathematics Tianjin Polytechnic University Tianjin 300160 China

K. Nakajo and W. Takahashi in 2.03 proved the strong convergence theorems for nonex-pansive mappings, nonexpansive semigroups, and proximal point algorithm for zero point of monotone operators in Hilbert spaces by using the hybrid method in mathematical programming. The purpose of this paper is to modify the hybrid iteration method of K. Nakajo and W. Takahashi through the monotone hybrid method, and to prove strong convergence theorems. The convergence rate of iteration process of the monotone hybrid method is faster than that of the iteration process of the hybrid method of K. Nakajo and W. Takahashi. In the proofs in this article, Cauchy sequence method is used to avoid the use of the demiclosedness principle and Opial＇s condition.

关键词： Hybrid method nonexpansive mapping nonexpansive semigroup proximal point algorithm strong convergence

Research on Rapid Response Schematic Design for Flexible Transfer Line CAPP-Based

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厦门大学学报（自然科学版） 2002年第S1期41卷 174-175页

作者： GAO Ju-hong 1, XU Yan-shen 2.(1. department of Industrial Engineering, School of Management, tianjin University, 2. department of Mechanical Engineering, School of Management, tianjin Univers ity, tianjin 300072, china)

To meet the market requirements for Flexible Transf er Line (FTL), which consists of modular NC machining tools of high quality and co st saving, the methodologies and technologies of client-oriented FTL rapid resp onse schematic design CAPP-based, one of the key techniques, are presented in t his paper. In order to achieve this purpose, an integrated system for integrated design of CAD/CAPP/FTL with box-type parts is realized. In this paper, firstly the theory of the conceptual design of FTL based on CAPP is established and the software architecture is developed. The global-domain pr oduct model is put forward to meet with data representation. After the manufactu ring feature is analyzed and decomposed for machining operations, the feature-b ased part unified data model object-oriented is built. Secondly the knowledge- based CAPP system data model is established. The process planning unit model is formed by work element (WE), which is tool-cell based function abstraction meth od, and has unified layers with respect to designing and manufacturing. With WEs through dynamic response and simultaneous structure in process planning, the pr inciple solution for CAPP function system can be implemented. Lastly the mapping from process domain to module design domain is built. The unidirectional select ion process based on fuzzy matching technology is easily dealt with computer. Th e algorithm of decision with fuzzy synthetic evaluation method and technology is applied to estimate the feasibility of the results in local working procedure o f modular NC machine tools and make decision of designs in overall FTL, which co nsists of many different factors. The example shows that the rapid response desi gn in bidding-based FTL scheme design is realized.

关键词： CAPP flexible transfer line product model rapi d response design

Automorphisms with order three of affine Lie algebras

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Chinese Science Bulletin 1998年第21期43卷 1793-1798页

作者： JIN Quanqin 1,2.and HOU Zixin 2.1. department of Mathematics, Hebei University, Baoding 071002. {2. 2. department of Mathematics, Nankai University, tianjin 300071, {2. department of Mathematics Hebei University Baoding China department of Mathematics Nankai University Tianjin China

Some properties of automorphisms of affine Lie algebras are presented. Automorphisms with order three are classified up to conjugacy, and their fixed point sets are also computed. As a corollary, it is proved that two... 详细信息

关键词： affine Lie algebra automorphism of order three first (second) kind of automorphism.

AN EXPERIMENTAL STUDY OF THE LARGE SCALE COHERENT STRUCTURES IN A FORCED FREE SHEAR LAYER

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Acta Mechanica Sinica 1990年第1期6卷 9-14页

作者： Zhang Hongquan Shu Wei, department of mechanics, Tianfin University, {2., china 1. department of mechanics Tianjin University Tianjin China

The dynamic characteristics of the large scale coherent structures in a forced free shear layer are experi- mentally studied by means of flow visualization. The quantitative measurements are acquired by the use of a LDV. It is shown that the development of the coherent structures can be greatly influenced by upstream artificial perturbations and as a result the mixing in the layer can be controlled. Like vortex merging, vortex splitting is also a common evolu- tion pattern in the development of the coherent structures.

关键词： large scale coherent structure vortex merging vortex splitting

RuCl_3·3H_2. Mediated Olefin Isomerizations in Ionic Liquids: A Highly Recyclable System for Olefin Isomerizations

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Chemical Research in Chinese Universities 2012年第1期28卷 67-69页

作者： SHAO Ming-bo1, LIU Gui-yan2. ZHAO Jing-jing1, WANG Xiao-yu1 and WANG Jian-hui1 1. department of Chemistry, College of Science, tianjin University, tianjin 300072, P. R. china 2. tianjin Key Laboratory of Structure and Performance for Functional Molecule, College of Chemistry, tianjin Normal University, tianjin 300387, P. R. china department of Chemistry College of Science Tianjin University Tianjin 300072 College of Chemistry Tianjin Normal University Tianjin Key Laboratory of Structure and Performance for Functional Molecule Tianjin 300387

Herein lies a convenient and highly efficient method of olefin isomerization in the presence of RuCl3？3H2. in ionic liquid（IL）. More importantly, RuCl3？3H2. is a robust and recyclable catalyst. Nine cycles of RuCl... 详细信息

关键词： Ruthenium trichloride Ionic liquid Olefin isomerization

Experimental study on the effect of gaseous and particulate emission from an ethanol fumigated diesel engine

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Science china(Technological Sciences) 2010年第12期53卷 3294-3301页

作者： YAO ChunDe1, ZHANG ZhiHui1,2. CHEUNG ChenShun2.& XU GuangLan1 1 State Key Laboratory of Engines, tianjin University, tianjin {2., china 2.department of Mechanical Engineering, The Hong Kong Polytechnic University, Hong Kong, china 1. State Key Laboratory of Engines Tianjin University Tianjin 300072 China2. Department of Mechanical Engineering The Hong Kong Polytechnic University Hong Kong China

Experiments were conducted on a four-cylinder direct-injection diesel engine with 10% and 2.% of the engine load taken up by fumigation ethanol injected into the air intake of each cylinder, to investigate the gaseous, particulate mass (PM) emissions, and number concentration and size distribution of the engine under five engine loads at the maximum torque engine speed of 1800 r/min. The experimental results show that at low engine loads, the brake thermal efficiency (BTE) decreases with increase in fumigation ethanol; but at high engine loads, the BTE is not significantly changed by fumigation ethanol. Fumigation ethanol can effectively decrease in brake specific nitrogen oxides (BSNOx), particulate mass and number emissions but significantly increase in brake specific hydrocarbon (BSHC), brake specific carbon monoxide (BSCO) and proportion of BSNO/BSNO2. Also, the geometrical mean diameter of the particles (GMD) increases with increase in engine load but the diameter is not changed by fumigation ethanol in all cases.

关键词： diesel engine ethanol particulate number emissions