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Journal of central south university 2000年第1期12卷 29-33页

作者： LI Yuan gao,ZHANG Quan ru,FANG Zheng(college of Chemistry and Chemical Engineering, central south university of Technology, changsha 410083, china) 1. college of Chemistry and Chemical Engineering Central South University of Technology 410083 Changsha China

In order to calculate the activity coefficients of water in aqueous solution of metal electrolytes, a simplified model predicting them in ternary or multicomponent solutions with common anions from the activity data of water of the corresponding binary systems has been developed based on an assumption that the electrolytes in the solution are treated as independent particles instead of their ion forms, and the interaction of the salt( i ) salt( j ) pair in the solution is assumed to be much weaker than that of water salt pair due to the common anions of both of salts. The model was applied to the systems such as KCl H 2O NaCl, MCl H 2O M′Cl 2 (M represents Na and K, M′ represents Ca and Ba) and KCl H 2O NaCl BaCl 2 with satisfying results. The interchange energies of the studied component pairs between water and salts have also been determined by the corresponding binary aqueous solutions.

关键词： activity of water electrolyte thermodynamic model interchange energy

Preparation of well-defined polystyrene/silica hybrid nanoparticles by ATRP

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science china Chemistry 2008年第1期51卷 51-57页

作者： OU BaoLi1,2 LI DuXin2 1 college of Chemistry and Chemical Engineering,Hunan university of science and Technology,Xiangtan 411201, china 2 State Key Laboratory of Powder Metallurgy,central south university,changsha 410083, china 1. college of Chemistry and Chemical Engineering Hunan University of Science and Technology Xiangtan 411201 China 2. State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

Immobilization of the atom transfer radical polymerization (ATRP) macroinitiators at the silica nanoparticle surfaces was achieved through surface modification with excess toluene-2,4-diisocynate (TDI), after which the residual isocyanate groups were converted into ATRP macroinitiators. Structurally well-defined polystyrene chains were grown from the nanoparticle surfaces to yield individual particles composed of a silica core and a well-defined, densely grafted outer polystyrene by ATRP, which was initiated by the as-synthesized silica-based macroinitiator. FTIR, NMR and gel permeation chro-matography (GPC) were used to characterize the polystyrene/silica hybrid particles.

关键词： silica nanoparticles surface modification atom transfer radical polymerization polystyrene hybrid particle

Preparation of polystyrene/silica nanocomposites by radical copolymerization of styrene with silica macromonomer

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science china Chemistry 2007年第3期50卷 385-391页

作者： OU BaoLi1,2 & LI DuXin2 1 college of Chemistry and Chemical Engineering, Hunan university of science and Technology, Xiangtan 411201, china 2 State Key Laboratory of Powder Metallurgy, central south university, changsha 410083, china 1. college of Chemistry and Chemical Engineering Hunan University of Science and Technology Xiangtan 411201 China 2. State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

A two-stage process has been developed to generate the silica-based macromonomer through surface-modification of silica with polymerizable vinyl groups. The silica surfaces were treated with excess 2,4-toluene diisocynate (TDI), after which the residual isocyanate groups were converted into polymerizable vinyl groups by reaction with hydroxypropylacrylate (HPA). Thus, polystyrene/silica nanocomposites were prepared by conventional radical copolymerization of styrene with silica macromonomer. The main effecting factors, such as ratios of styrene to the macromonomer, together with polymerization time on the copolymerization were studied in detail. FTIR, DSC and TGA were utilized to characterize the nanocomposites. Experimental results revealed that the silica nanoparticles act as cross-linking points in the polystytene/silica nanocomposites, and the glass transition temperatures of the nanocomposites are higher than that of the corresponding pure polystyrene. The glass transition temperatures of nanocomposites increased with the increasing of silica contents, which were further ascertained by DSC.

关键词： silica nanoparticles surface modification styrene radical copolymerization nanocomposites

CALCULATION OF ELASTIC ERROR OF PLANAR MECHANISM—AN EQUIVALENT METHOD

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Journal of central south university 1999年第1期11卷 57-59页

作者： Wang Ailun Zhong Jue Chang Tiegang (college of Mechanical and Electrical Engineering, central south university of Technology, changsha 410083, china) college of Mechanical and Electrical Engineering Central South University of Technology Changsha410083 China

In rigid mechanism dynamic analysis, the equivalence theorem is often used due to its simplicity and perceivability. Based on conjugation and duality between inertia energy storing element and elastic energy storing element, the equivalence theorem is used in elastic error analysis of planar mechanism. A set of calculation formula of elastic error is introduced, and these equations are similar in expression form to the rigid dynamic equation. To demonstrate the method developed, a computation example is given.

关键词： planar mechanism elastic error equivalent flexibility

Synthesis of p-nitrophenol under normal pressure with A-1 phase transfer catalysis

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Journal of central south university of Technology 2001年第1期8卷 54-56页

作者： ZHONG Shi an, OUYANG Xi, ZHOU Chun shan, CHENG Ben cheng (college of Chemistry and Chemical Engineering, central south university, changsha 410083, china) 1. college of Chemistry and Chemical Engineering Central South University 410083 Changsha China

p nitrophenol is synthesized using p nitrochlorobenzene and sodium hydroxide with phase transfer catalyst. Several reaction factors, such as catalyst type, the amounts of catalysts and sodium hydroxide, the concentration of sodium hydroxide solution as well as reaction time, affect greatly the yield of p nitrophenol. The optimum reaction conditions are as follows: A 1 used as phase transfer catalyst whose consumption is 6% (mole fraction) of p nitrochlorobenzene; the molar ratio of sodium hydroxide to p nitrochlorobenzene is 3:1; the concentration of sodium hydroxide solution is 50% (mass fraction). Nitrobenzene, whose molar amount is 2.45 times as much as that of p nitrochlorobenzene; reaction time is 7 h at 140 ℃ under normal pressure. The final yield of p nitrophenol is 83.6%.

关键词： phase transfer catalysis p nitrophenol synthesis

Inhibitory effects of cariporide on LPC-induced expression of ICAM-1 and adhesion of monocytes to smooth muscle cells in vitro

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Acta Pharmacologica Sinica 2006年第10期27卷 1326-1332页

作者： Zhi LI Tao SONG Gui-zhen LIU Li-ying LIU~2 Department of Pharmacology,pharmaceutical college,central south university,changsha 410078,china Department of Pharmacology Pharmaceutical College Central South University Changsha 410078 China

Aim:To explore the effects of cariporide on the expression of intercellular adhe-sion molecule-1(ICAM-1)and the adhesion of monocytes to vascular smoothmuscle cells(SMC)in ***:Monocytes were isolated from humanperipheral blood by the Ficoll-Hypaque *** expression of ICAM-1 inSMC was detected by *** adhesion of monocytes to SMC was stimu-lated by lysophosphatidylcholine(LPC).The adhesion ratio of monocytes wasassayed by measuring protein *** intracellular pH([pH]i)of SMC wasmeasured with 2’,7’-bis(2-carboxyethyl)-5,6-carboxyfluorescein(BCECF).Results:Preincubation of SMC with LPC alone(5 μg/mL)for 4 h markedly enhanced theexpression of ICAM-1 in SMC and the rate of the adhesion of monocytes to SMCin a concentration-dependent and time-related *** simultaneously alsoinduced an increase of[pH]ivalue in *** concentration-dependentlyreduced the adhesion ratio of monocytes to SMC and the expression of ICAM-1in SMC induced by *** inhibitory effects of cariporide on the expression ofICAM-1 in SMC and the adhesion of monocytes to SMC also were associatedwith blocking LPC-induced elevation of the[pH]ivalue in ***:LPC-induced monocyte-SMC adhesion may be mediated via activation of theNa~+/H~+(NHE)*** action mechanism of cariporide may be related withinhibition of activation of the Na~+/H~+ exchanger of plasma membranes and ICAM-1expression on the surface of SMC induced by LPC.

关键词： Na~+/H~+ exchanger cariporide lysophosphatidylcholine intercellular adhesion molecule-l monocyte smooth muscle cells

Experiment and mechanism of vibration liquefaction and compacting of saturated bulk solid

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Journal of central south university of Technology 2001年第1期8卷 34-39页

作者： WU Ai xiang,GU De sheng,SUN Ye zhi,HU Hua (college of Resources, Environment and Civil Engineering, central south university, changsha 410083, china) 1. college of Resources Environment and Civil Engineering Central South University 410083 Changsha China

The paper studies the probability of industrial application of vibration liquefaction of bulk solid from the opposite point of view, and proposing turning its harmful effects into benefits. Utilizing a new device of vibration liquefaction and by compacting saturated bulk solid, a set of additional device for experiment was designed. These experiments examined the problems related to vibration liquefaction of fine ores and tailings on the basis of DSA 1 type direct shear apparatus, including models of straight tubes, curved tubes and a sandbox. The changing properties of tailings under vibration and the mechanism of vibration liquefaction and compacting of tailings were studied, and future application of the technique to mines has been put forward.

关键词： vibration liquefaction compacting mechanism

Effects of water phase concentration on the emulsion polymerization of polyaniline

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Journal of central south university of Technology 2001年第2期8卷 140-142页

作者： PAN Chun yue 1,CHEN Zhen hua 2,HUANG Yong li 1,HUANG Ke long 1 (1.college of Chemistry and Chemical Engineering, central south university, changsha 410083, china 2.Department of Materials science and Engineering, central south university, Cha 1. college of Chemistry and Chemical Engineering Central South University 410083 Changsha China 2. Department of Materials science and Engineering Central South University 410083 Changsha China

The emulsion polymerization of aniline in three phase system of xylene functionalized protonic acid water was carried out using (NH 4) 2S 2O 4 as oxidant. The influences of water phase concentration on the viscosity, conductivity, transmittance of polyaniline(PAN) latex and its powders were studied. The results show that the properties of PAN prepared through the emulsion polymerization are influenced by the amount of water used in the polymerization. The morphology of PAN varies with the water phase concentration used in the polymerization, which may result in the change of properties of PAN latex and its powders. When the volume fraction of water (φ) is about 20% 30%, the prepared PAN powder has higher conductivity, and the PAN latex has appropriate viscosity and particle size. The consumption of xylene was reduced at high φ value.

关键词： polyaniline emulsion polymerization water concentration property

Decentralized Robust Control for Large Scale Interconnected Uncertain Systems with Time delay

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Journal of central south university 2000年第1期12卷 49-52页

作者： TANG Zhao hui,WU Min,GUI Wei hua,XIE Yong fang (college of Information Engineering, central south university of Technology, changsha 410083, china) 1. college of Information Engineering Central South University of Technology 410083 Changsha China

For a class of interconnected time delay uncertain systems satisfing the matching conditions, the sufficient condition for decentralized stabilization feedback control laws is derived based on Lyapunov stability theorem. This condition is expressed as the solvability problem of linear matrix inequalities(LMI). It can be easily determined whether or not, it is feasible and one can easily obtain the decentralized stabilizing state feedback matrices via LMI techniques. The method overcomes the limitations of the existing algebraic Riccati equation method. The given example shows the application of the method.

关键词： uncertainties time delay linear matrix inequality decentralized control robustness

Upgrade and separation of Co from solution with low-grade Co

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中南工业大学学报：英文版 2001年第4期8卷 249-251页

作者： ZHONG Shi an,ZHOU Chun shan,OU Yang xi,CHENG Ben cheng(college of Chemistry and Chemical Engineering, central south university, changsha 410083, china) 1. college of Chemistry and Chemical Engineering Central South University 410083 Changsha China

Upgrade and separation of Co from solution with low grade Co were studied. In the solution, the content of Co is about 1 g·L -1 , while that of Ni, Zn, Mn, Mg, Si and Ca is 0.145, 1.108, 0.119, 6.672, 0.026 and 0.200 g·L -1 , respectively. After absorbed with absorbent G-1, the content of Co in the solution is less than 1 mg·L -1 , the average loss rate of Co is 0.07%, while the average loss rate of Mg is 67.92%. It is demonstrated that the absorbent has selectivity to absorb Co. After the absorbent was eluted with HCl at room temperature, the solution with higher content of Co was obtained. Through being evaporated and concentrated, the contant of Co in the solution can be upgraded to 26.6 g·L -1 . At the same time, most of Si, Mg is removed, the total recovery of Co can reach as high as 98.7%. The content of Pb, Ni, Cu, Zn, Mn in the discharge solution is 1.00, 0.26, 0.21, 0.09, 0.15 mg·L -1 , respectively, and the discharge solution can reach the national discharge standard. CoCl 2 solid can be obtained and can reach chemical purity.

关键词： Co upgrade separation