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The Practice Model and Optimization Strategy of the New-type Rural Social Old-age Insurance System

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学术界 2010年第7期 282-285页

作者： Yang Faxiang Sociology Department,east china university of science and technology

Paragraph 1 Since 1986,the exploration of national rural social old-age insurance started. In 1991,based on the practicing on experimental units,the whole work was gradually launched.

关键词： type The Practice Model and Optimization Strategy of the New-type Rural Social Old-age Insurance System

Study on Activated Bentonite Applied to tert-Butylation of Toluene

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china Petroleum Processing & Petrochemical technology 2011年第1期13卷 38-44页

作者： Chen Linbo Shi Li (Department of Petroleum Processing,east china university of science and technology,Shanghai 200237) E china Univ Sci & Technol Dept Petr Proc Shanghai 200237 Peoples R China

tert-Butylation of toluene with tert-butanol used as the alkylating agent was investigated over the activated bentonite and HY zeolite used as the *** influences of various butylation reaction parameters,including the toluene/tert-butanol ratio,the reaction temperature,and the space velocity were *** optimal results were obtained at a reaction temperature of 180 ℃,a space velocity of 4 h-1,and a mole ratio of toluene to tert-butanol equating to *** structure and acidic properties of catalyst were characterized by the BET method and the Fourier transform infrared (FTIR) *** with the HY zeolite,the activated bentonite possessed high activity for toluene conversion and high para-selectivity because it had larger pore diameter,smaller micropore surface area and higher ratio of total Lewis acids to total Br nsted acids.

关键词： t-butylation activated bentonite p-tert-butyltoluene pore diameter Lewis acid

Manufacture of the Ultrafine Grain WC/Co Cemented Carbides by Combined Sintering Processing

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 208-213页

作者： Binghai Liu Yue Zhang Shixi Ouyang Qikai Li(Institute of Technical Physics and Chemistry, east china university of science and technology , Shanghai 200237, china)(Material science and Engineering School. university of science and technology Beijing, Beijing 100083, china)(State Key Laboratory for Synthesis and Processing of Advanced Materials. Wuhan university of science and technology, Wuhan 430070, china,) E china Univ Sci & Technol Inst Tech Phys & Chem Shanghai 200237 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Wuhan Univ Sci & Technol State Key Lab Synth & Proc Adv Mat Wuhan 430070 Peoples R China

A new kind of sintering process, combined sintering process. i.e. vacuum sintering plus hot isolate pressure sintering (HIP), was introduced for producing ultrafine WC-10% Co (mass fraction. so as the follows) cemented carbides. The effects of some processing parameters on the microstructure and mechanical properties of the obtained cemented carbides were studied. The results show that the rapid shrinkage and the pronounced densification of tile cemented carbides took place during the vacuum sintering stage, which is intinaately correlated with the local liquid sintering occurred during this earl} sintering stage for the high surface activity of ultrafine WC-Co powder. The way of high pressure imposing. isothermal treatment cycle during *** sintering and HIP sintering stage directly influence the densitication of compacts and the mechanical properties of the produced WC-10%Co cemented carbides.

关键词： ultrafine WC-Co cemented carbides vacuum sintering HIP sintering

Large-eddy simulations and vortex structures of turbulent jets in crossflow

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science china(Physics,Mechanics & Astronomy) 2007年第1期50卷 118-132页

作者： GUAN Hui1,2 & WU ChuiJie2 1 School of Mechanical and Power Engineering,east china university of science and technology,Shanghai 200237,china 2 Research Center for Fluid Dynamics,PLA university of science and technology,Nanjing 211101,china 1. School of Mechanical and Power Engineering East China University of Science and Technology Shanghai 200237 China 2. Research Center for Fluid Dynamics PLA University of Science and Technology Nanjing 211101 China

Using the method of large-eddy simulation, the 3-dimensional turbulent jets in crossflow with stream-wise and transverse arrangements of nozzle are simulated, emphasizing on the dynamical process of generation and evolution of vortex structures in these flows. The results show that the basic vortex structures in literatures, such as the counter-rotating vortex pair, leading-edge vortices, lee-side vortices, hanging vortices, kidney vortices and anti-kidney vortices, are not independent physical substances, but local structures of the basic vortex structure of turbulent jets in crossflow-the 3-D stretching vortex rings originating from the orifice of the nozzle, which is discovered in this study. Therefore, the most important large-scale structures of turbulent jets in crossflow are unified to the 3-D vortex rings which stretch and twist in stream-wise and swing in transverse directions. We also found that the shedding frequencies of vortex rings are much lower than the one corresponding to the appearance of leading-edge and lee-side vortices in the turbulent jets.

关键词： turbulent jet in crossflow coherent structure large-eddy simulation

The Preparation and Application of two New Types of Oxazaborolidines

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Chinese Chemical Letters 2000年第5期11卷 381-382页

作者： Guo Bin RONG Xing Ming LI Yong ZHANG (Department of Chemistry east china university of science and technology. Shanghai 200237) E china Univ Sci & Technol Dept Chem Shanghai 200237 Peoples R China

Two new type of 1,3,2-oxazaborolidines were prepared from (Is,2s)-2-amino-1-(4-nitrophenyl)-propane-1-3-diol and were used as catalyst in the asymmetric reduction of acetophenone. The influence of the reaction temperature as well as the effect of the structure of catalyst on the enantioselectivity was investigated. The origin of the products' configuration was discussed.

关键词： oxazaborolidine asymmetric catalytic reduction prochiral ketone

CONTROLLED/"LIVING" RADICAL POLYMERIZATION OF STYRENE IN AN AQUEOUS DISPERSION SYSTEM

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Chinese Journal of Polymer science 2002年第5期20卷 445-451页

作者： Bin Zhang Zhao-bin Zhang Xiao-long Wan Chun-pu Hu Sheng-kang Ying Lab of Living Polymerization, east china university of science and technology.Shanghai 200237,china E china Univ Sci & Technol Lab Living Polymerizat Shanghai 200237 Peoples R China

Atom transfer radical polymerization (ATRP) of styrene catalyzed by cuprous (CuX)/1,10-phenanthroline (Phen) and CuX/CuX2/Phen was conducted in an aqueous dispersed system. A stable latex was obtained by using ionic surfactant sodium lauryl sulfonate (SLS) or composite surfactants, such as SLS/polyoxyethylene nonyl phenyl ether (OP-10), SLS/hexadecanol and SLS/OP-10/hexadecanol, Among which SLS and SLS/OP-10/hexadecanol systems established better dispersed effect during the polymerization, It was found that Phen was a more suitable ligand than N,N,N',N',N'-pentamethyldiethylenetriamine (PMDETA) to maintain an appropriate equilibrium of the activator Cu(I) and the deactivator Cu(II) between the organic phase and the water phase, The effect of several initiators (such as EBiB, CCl4 and 1-PEBr) and the temperature on such a kind of ATRP system was also observed. The number-average molar mass (M-n) of polystyrene (PS) increased with the conversion and the molar mass distribution (M-w/M-n) remained narrow. These experimental data show that the polymerization could be controlled except for the quick increase of monomer conversion and the number-average molar mass of PS in the initial stage of polymerization. Furthermore, the initiator efficiency was found to be low (similar to57%) in CuX/Phen catalyzed system. To overcome this problem, Cu(II)X-2 (20 mol%-50 mol% based on CuX) was introduced into the polymerization system. In this case, higher initiator efficiency (60%-90%), low M-w/M-n of PS (as low as 1.08) were achieved and the molar masses of the PS fit with the theoretical ones.

关键词： controlled/'living' radical polymerization polystyrene water dispersed polymerization 1,10-Phenanthroline

Removal of Trace Olefins from Aromatics by Catalytic Alkylation Using 1-Alkyl-3-methylimidazolium Bromochloroaluminate Catalyst

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china Petroleum Processing & Petrochemical technology 2011年第2期13卷 14-18页

作者： Sun Yu Shi Li(State Key Laboratory of Chemical Engineering,east china university of science and technology,Shanghai 200237) E china Univ Sci & Technol State Key Lab Chem Engn Shanghai 200237 Peoples R China

Removal of trace olefins from aromatic liquids had been investigated in the presence of various ionic liquids like 1-ethyl-3-methylimidazoliurn bromochloroaluminate （EMIMBr-AlCl3）, 1-butyl-3-methylimidazolium bromochloroaluminate （BMIMBr-AlCl3）, l-hexyl-3-methylimidazolium bromochloroaluminate （HMIMBr-AlCl3）, and 1-octyl-3-methylimidazolium bromochloroaluminate （OMIMBr-A1C13）. It was found that the longer the alkyl chain of ionic liquid cations was, the higher the olefins conversion would be. OMIMBr-AlCl3 （with 0.67 molar fraction of AlCl3） had an obvious performance on olefins removal. The influences of various reaction parameters such as the dosage of catalyst, the reaction temperature, and the reaction time on the reaction catalyzed by OMIMBr-AlCl3 were investigated. Under optimum reaction conditions, a higher than 99% conversion of olefins was achieved. The preliminary results revealed that the process could save time, consume less energy, separate products easier, and cause less pollution to the environment.

关键词： ionic liquids olefins removal 1-alkyl-3-methylimidazolium bromochloroaluminate aromatic

θ-PSO: a new strategy of particle swarm optimization

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Journal of Zhejiang university-science A(Applied Physics & Engineering) 2008年第6期9卷 786-790页

作者： Wei-min ZHONG1,2, Shao-jun LI1,2, Feng QIAN1,2 (1State Key Laboratory of Chemical Engineering, east china university of science and technology, Shanghai 200237, china) (2Automation Institute, east china university of science and technology, Shanghai 200237, china) State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai China Automation Institute East China University of Science and Technology Shanghai China

Particle swarm optimization (PSO) is an efficient, robust and simple optimization algorithm. Most studies are mainly concentrated on better understanding of the standard PSO control parameters, such as acceleration coefficients, etc. In this paper, a more simple strategy of PSO algorithm called θ-PSO is proposed. In θ-PSO, an increment of phase angle vector replaces the increment of velocity vector and the positions are decided by the mapping of phase angles. Benchmark testing of nonlinear func- tions is described and the results show that the performance of θ-PSO is much more effective than that of the standard PSO.

关键词： Particle swarm optimization (PSO) Phase angle Benchmark function

Ni-loaded Catalyst Containing Activated Clay for Maleic Anhydride Hydrogenation to Succinic Anhydride

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china Petroleum Processing & Petrochemical technology 2011年第4期13卷 35-40页

作者： Tian Weiping Guo Shaofei Shi Li (The State Key Laboratory of Chemical Engineering, east china university of science and technology, Shanghai 200237) E china Univ Sci & Technol State Key Lab Chem Engn Shanghai 200237 Peoples R China

In this work, the hydrogenation of maleic anhydride to succinic anhydride in the presence of 5 m%Ni/clay catalysts was investigated. These catalysts were characterized by X-ray diffraction （XRD）, H2 temperature programmed reduction （TPR） and thermogravimetric analysis （TGA） techniques. The XRD and TPR studies showed that Ni was present as Ni2＋ on the support, which indicated that there were no elemental nickel （Ni^0） and Ni203 species in the unreduced samples. Increasing of calcination temperature to 650 ℃ leads to destruction of the support structure observed in TGA, while the catalyst sample calcined at 550 ℃ exhibits better performances than other samples. The ideal conversion of maleic anhydride （97.14%） and selectivity of succinic anhydride （99.55%） were realized at a reaction temperature of 180 ℃ and a weight hourly space velocity of 4 h^-1 under a reaction pressure of 1 MPa.

关键词： maleic anhydride hydrogenation succinic anhydride nickel