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Communications in Theoretical Physics 2005年第3期43卷 567-576页

作者： ZHOUShi-Qi InstituteofModernStatisticalMechanics ZhuzhouInstituteofTechnologyZhuzhou412008China

The accuracy of hard core attractive Yukawa (HCAY) potential and adhesivehard sphere (AH) potential in representing the structure factor of short range square well potentialand Asakura and Oosawa (AO) depletion potential is examined by comparing theoretical predictionswith the existing simulation data and the present numerical results from the non-linear optimizedrandom phase approximation closure for Ornstein—Zernike equation. For the case of square-well (SW)potential, it is shown that the structure factor of HCAY potential based on a recently proposedsemi-analytical expression for the radial distribution function can describe the structure factor ofSW potential with reduced well width λ ≤ 2 only if the reduced contact potential βε_(sw) ≤0.25, while the analytical expression for the structure factor of AH potential under Percus-Yevick(PY) approximation completely fails for the case of λ > 1.2. For the case of AO depletionpotential, the domain of validity of both HCAY potential and AH potential is complementary. With theabove analysis and considering the solid-liquid transition of the AH potential with an adhesiveparameter τ below 1.31 cannot be predicted by modified weighted density approximation, the roleplayed by the HCAY potential about the mapping manipulation should not be ignored.

关键词： colloidal dispersion structure factor

Aggregation and Gelation Kinetics for RLCA in Concentrated Spherical colloidal dispersion Systems

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NEW METHOD FOR EFFECTIVE VISCOSITY OF colloidal dispersionS WITH PERIODIC MICROSTRUCTURES

2007年全国高分子学术论文报告会

作者： Xie Jian-iun 1.College of Materials Science and Engineering, 2.Institute of Rheology Mechanics and Materials Engineering,Central South University of Forestry and Technology,Changsha,410004,Hunan,China

＜正＞Light scattering,including static light scattering and small-angle light scatterings is a very useful *** is used to investigate the aggregation and gelation kinetics of concentrated colloidal dispersion systems.A scattering structure factor S（q）of a colloidal gel in a q range of 4 orders of magnitude has been *** results exhibit simultaneously two types of structure information:mass fractal scaling within clusters that

关键词： Fractal Aggregation Gelation Kinetics RLCA colloidal dispersion

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Acta Mathematica Scientia 1999年第2期19卷 148-157页

作者：顾国庆余建华 School of Systems Science and Systems Engineering University of Shanghai for Science and Technology Shanghai 200093 China Department of Physics The Chinese University of Hong Kong Shatin New Territories Hong Kong

One of the central theoretical problems in the colloid field is to determine the rheological relation between the macroscopic properties of colloidal suspensions and the microstructures of the systems. In this work, the authors develop a method of transformation field by which one call calculate the effective viscosity of an incompressible: viscous fluid containing colloidal particles (either solid particles: or liquid drops) fixed at the points of a periodic lattice. The effective viscosity of a colloidal dispersion of spherical particles is calculated. The predictions of the theory are in good agreement with the Einstein's formula for suspensions and the Taylor's formula for emulsions at low particle concentrations. At higher particle concentrations, the theory reproduces the results of Nunan and Keller. The method is also applicable to the viscosity of colloidal systems with non-spherical particles.

关键词： colloidal dispersion effective viscosity suspension emulsion

A THEORETICAL RESEARCH TO EFFECTIVE VISCOSITY OF colloidal dispersionS

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Applied Mathematics and Mechanics(English Edition) 2000年第3期21卷 275-282页

作者：顾国庆余建华 School of Computer Engineering University of Shanghai for Science and Technology Shanghai P R China Physics Department The Chinese University of Hong Kong Shatin New Territories Hong Kong P R China

colloidal dispersions are common in nature with wide industrial applications. One of the central theoretical problems in the field is to determine the rheological properties of the colloidal dispersion from the microstructures of the systems. Because of the difficulties associated with the boundary-value problems of the many-particle system, existing theories for colloidal suspensions are limited to low particle concentrations. In this work, a method of transformation field is developed by which one can calculate the effective viscosity of an incompressible viscous fluid containing colloidal particles ( either solid particles or liquid drops). The predictions of the theory are in goad agreement with the Einstein's formula for suspensions and the Taylor's formula for emulsions at low particle concentrations. At higher particle concentrations, the results of Nunan and Keller are produced. The method is also applicable to the viscosity of colloidal systems with non-spherical particles.

关键词： multiphase flow colloidal dispersion suspension emulsion

Nanoscale graphene oxide sheets as highly efficient carbocatalysts in green oxidation of benzylic alcohols and aromatic aldehydes

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Chinese Journal of Catalysis 2017年第4期38卷 745-757页

作者： Alireza Sedrpoushan Masoud Heidari Omid Akhavan Department of Chemical Technologies Iranian Research Organization for Science and Technology (IROST) P.O. Box 33535‐111 Tehran Iran Department of Physics Sharif University of Technology P.O. Box 11155‐9161 Tehran Iran Institute for Nanoscience and Nanotechnology Sharif University of Technology P.O. Box 14588‐89694 Tehran Iran

Nanoscale graphene oxide(NGO)sheets were synthesized and used as carbocatalysts for effectiveoxidation of benzylic alcohols and aromatic *** oxidation of alcohols in the presence ofH2O2at80°C,the NGOs(20%mass fraction)as carbocatalysts showed selectivity toward *** rate and yield of this reaction strongly depended on the nature of substituents on the ***4‐nitrobenzyl alcohol,<10%of it was converted into the corresponding carboxylic acid *** contrast,4‐methoxybenzyl alcohol and diphenylmethanol were completely converted into thecorresponding carboxylic acid and ketone after only9and3h,*** conversion ratesfor oxidation of aromatic aldehydes by NGO carbocatalysts were higher than those for alcohol *** all the aldehydes,complete conversion to the corresponding carboxylic acids wasachieved using7%(mass fraction)of NGO at70°C within2–*** mechanisms for NGOcarbocatalyst structure‐dependent oxidation of benzyl alcohols and structure‐independent oxidationof aromatic aldehydes are discussed.

关键词： Carbocatalyst Nanoscale graphene oxide Green chemistry Oxidation Metal‐free catalyst colloidal dispersion

POLYMER COLLOIDS FORMED BY POLYELECTROLYTE COMPLEXATION OF VINYL POLYMERS AND POLYSACCHARIDES IN AQUEOUS SOLUTION

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Chinese Journal of Polymer Science 2013年第1期31卷 39-49页

作者： Hui-dan Liu Takahiro Sato Department of Macromolecular Science Osaka University

The polyelectrolyte complex formed from the polyanion and polycation was studied by turbidimetry, static and electrophoretic light scattering, and elementary analysis. Sodium salts of polyacrylate （PA） and heparin （Hep） were chosen as the polyanion, and hydrochloric salts of poly（vinyl amine）（PVA） and chitosan （Chts） as the polycation. Although these vinyl polymers and polysaccharides have remarkably different backbone chemical structures and linear charge densities, all the four combinations PA-PVA, PA-Chts, Hep-PVA, and Hep-Chts provide almost stoichiometric polyelectrolyte complexes which are slightly charged owing to the adsorption of the excess polyelectrolyte component onto the neutral complex. The charges stabilize the complex colloids in aqueous solution of a non-stoichiometric mixture, and the aggregation number of the complex colloids increases with approaching to the stoichiometric mixing ratio. The mixing ratio dependence of the aggregation number for the four complexes is explained by the model proposed in the previous study.

关键词： Polyelectrolyte complex colloidal dispersion Polyacrylate Poly(vinyl amine) Heparin Chitosan Lightscattering.

Dielectric Relaxations of PNIPAM colloidal dispersions at the Coil-Globule Transition

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Dielectric Relaxations of PNIPAM Colloidal Dispersions at th...