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Tolerance of Physocypria kraepelini (Crustacean, Ostracoda) to water-borne ammonia, phosphate and pH value

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Journal of Environmental sciences 2009年第11期21卷 1575-1580页

作者： YU Na, CHEN Shimei, LI Erchao, CHEN Jiayan, CHEN Liqiao School of Life science, east china Normal {3., shanghai 200062, china [a]School of Life science East China Normal University Shanghai 200062 China

This study evaluated the median lethal concentration （LC50） and safe concentration of water-borne ammonia, phosphate and pH value on Physocypria kraepelini, a freshwater Ostracoda with a static renewal test system. The results indicated that the LC50 values of ammonia for P. kraepelini were 1026.71, 859.98, 771.79 and 583.82 mg/L at 24, 48, 72 and 96 h exposure, respectively, and the safe concentration range of ammonia for the long-term survival of P. kraepelini was less than 58.3. mg/L. The safe range of pH value for the survival of P. kraepelini was from 6.59 to 7.61. P. kraepelini has a high tolerance to ammonia, phosphate and pH value which are the main environmental factors in the serious eutrophication water.

关键词： ammonium phosphate Physocypria kraepelini

Characteristics of fMRI BOLD signal and its neurophysiological mechanism

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Progress in Natural science:Materials International 2007年第6期17卷 630-638页

作者： Zhao Xiaohu1,2, Wu Yigen3.and Guo Shengli3.1. College of Life sciences, Zhejiang university, Hangzhou 3.0058, china 2. Imaging Department of Tongji Hospital of Tongji university, shanghai 200065, china 3. College of Mathematics and Physics, Nanjing university of Information science and technology, Nanjing 210044, china) College of Life sciences Zhejiang University Hangzhou 310058 China Imaging Department Tongji Hospital Tongji University Shanghai 200065 China College of Mathematics and Physics Nanjing University of Information Science and Technology Nanjing 210044 China

The functional magnetic resonance imaging (fMRI) based on blood oxygen level dependent (BOLD) contrast has emerged as one of the most potent noninvasive tools for mapping brain function and has been widely used to explore physiological, pathological changes and mental activity in the brain. Exploring the nature and property of BOLD signal has recently attracted more attentions. Despite that great progress has been made in investigation of the characteristics and neurophysiological basis, the exact nature of BOLD signal remains unclear. In this paper we discuss the characteristics of BOLD signals, the nonlinear BOLD response to external stimuli and the relation between BOLD signals and neural electrophysiological recordings. Furthermore, we develop our new opinions regarding nonlinear BOLD response and make some perspectives on future study.

关键词： functional magnetic resonance imaging blood oxygen level dependent nonlinear response neural electrophysiological activity.

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 {3. and technology.shanghai 20023.,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

FOURIER PSEUDOSPECTRAL-FINITE DIFFERENCE METHOD FOR INCOMPRESSIBLE FLOW

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Journal of Computational Mathematics 1994年第4期12卷 312-329页

作者： Guo Ben-yu Xiong Yue-shan(shanghai university of science and {3., shanghai, china ) shanghai UNIV SCI & TECHNOL SHANGHAIPEOPLES R CHINA

A Fourier pseudospectral-finite difference scheme is proposed for unsteady Navier-Stokes equation. It is showed that the numerical solution keeps semi-discrete conservation. The strict error estimation is established.... 详细信息

关键词： Math FOURIER PSEUDOSPECTRAL-FINITE DIFFERENCE METHOD FOR INCOMPRESSIBLE FLOW

Thermal stability conditions of a weakly interacting Fermi gas in a weak magnetic field

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Progress in Natural science:Materials International 2009年第1期19卷 121-124页

作者： Fudian Mena,Hui Liub,Houyu Zhua a College of Physics science and technology,china {3. of Petroleum(east china),Dongying 257061,china b College of science,Anhui science and technology {3.,Fengyang 23.100,china [a]College of Physics science and technology China University of Petroleum (East China) Dongying 257061 China [b]College of Science Anhui Science and Technology University Fengyang 233100 China

On the basis of the results derived from pseudopotential method and ensemble theory,thermal stability of a weakly interacting Fermi gas in a weak magnetic field is studied by using analytical method of *** exact analytical expressions of stability conditions at different temperatures are given,and the effects of interactions as well as magnetic field on the stability of the system are *** is shown that there is an upperlimit magnetic field for the stability of the system at low temperatures,and there is an attractive dividing value at high *** attractive interaction is lower than the critical value,the stability of the system has no request for magnetic field,but if attractive interaction is higher than the dividing value,a lower-limit magnetic field exists for the stability of the system.

关键词： Fermi gas Interaction Heat capacity Stability

s-ordering operator expansions of quantum-mechanical fundamental representations and their applications

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science china(Physics,Mechanics & Astronomy) 2011年第12期54卷 2150-2154页

作者： FAN HongYi 1,3., XU YeJun 2 & YUAN HongChun 3.4 1 Department of Materials science and Engineering, university of science and {3. of china, Hefei 23.026, china 2 Department of Physics Electronic and Engineering, Chizhou university, Chizhou 247000, china 3.Department of Physics, shanghai Jiao Tong university, shanghai 20003., china 4 College of Optoelectronic Engineering, Changzhou Institute of {3., Changzhou 213.02, china 1. Department of Materials science and Engineering University of Science and Technology of China Hefei 230026 China3. Department of Physics Shanghai Jiao Tong University Shanghai 200030 China2. Department of Physics Electronic and Engineering Chizhou University Chizhou 247000 China4. College of Optoelectronic Engineering Changzhou Institute of Technology Changzhou 213002 China

We show that the quantum-mechanical fundamental representations, say, the coordinate representation, the coherent state representation, the Fan-Klauder entangled state representation can be recast into s-ordering operator expansion, which is elegant in form and has many applications in deriving new operator identities. This demonstrates that Dirac's symbolic method can be merged into Newton-Leibniz integration theory in a broad way.

关键词： s-ordering operator expansion operator identities quantum mechanical representation

A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： GE GuiXian1,JING Qun1 & LUO YouHua2,3.1 Key Laboratory of Ecophysics and Department of Physics,Normal College,Shihezi university,Xinjiang 83.003.china 2 School of science,{3. china university of science and technology,shanghai 20023.,china 3.Institute of Theoretical Physics,School of Physics and Information Optoelectronics,Henan university,Kaifeng 475004,china 1. Key Laboratory of Ecophysics and Department of Physics Normal College Shihezi University Xinjiang 832003 China2. School of Science East China University of Science and Technology Shanghai 200237 China3. Institute of Theoretical Physics School of Physics and Information Optoelectronics Henan University Kaifeng 475004 China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1 clusters with B *** geometries of CrnB clusters are similar to that of Crn+1 clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3.,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coupling way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties

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 {3. and technology. shanghai 20023.) 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

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 {3. and technology, shanghai 20023., china) (2Automation Institute, east china university of {3. and technology, shanghai 20023., 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