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Journal of Central South University of Technology 2007年第4期14卷 490-495页

作者：彭兵黄毅柴立元李国良程明明张晓飞 School of Metallurgical Science and Engineering Central South University

The effects of SN5040 and polyethylene glycol（PEG） individually and in combination on the dispersion stability of nano-TiO2 aqueous suspension were investigated by ultraviolet-visible absorption spectroscopy. The adsorption mechanism of these dispersants was detected by zeta potential, isothermal absorption and FTIR analysis. It is found that SN5040 is superior for stabilizing nano-TiO2 in aqueous suspension to PEG in basic region, and the optimum mass fraction of SN5040 addition is 3%. In the case of NaCl addition, the optimum value increases with .the increase of NaCl concentration in the solution. When the mixture of SN5040 and PEG is employed, the antagonism appears preponderant. When SN5040 and PEG are added sequentially, the synergistic reaction takes place. The synergistic reaction can be attributed to the mechanism that PEG adsorption decreases the electronic repulsion between SN5040 molecules, which results in the increase of SN5040 adsorption density. PEG is adsorbed by the interaction with the pre-adsorbed SN5040 layer. Furthermore, the modified inner wall latex paint with well dispersed nano-YiO2 suspension is endowed with excellent ultraviolet absorption and antibacterial properties.

关键词： polymer dispersant dispersion stability nano-TiO2 inner wall latex paint PEG adsorption

Preparation of SiO_2 Nanoparticles by Silicon and Their dispersion stability

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Journal of Wuhan University of Technology(Materials Science) 2005年第2期20卷 74-76页

作者：庞金兴 School of Science Wuhan University of TechnologyWuhan 430070China Prof

Silicon dioxide sol was synthesized by silicon in the presence of alkali catalyst. SiO_2 nanoparticles (size in 8-15 nm) aqueous dispersion was prepared by using dispersion and surface modification in situ. The effects of reaction time, temperature, medium pH value, dispersant and surface-modifier on their diameters, sizes distribution and dispersion stability were also *** experimental results show that the preparation method can effectively resolve the dispersion stability of SiO_2 nanoparticles in water.

关键词： nanoparticles forming in situ surface-modification size distribution dispersion stability

Preparation of SiO_2 Nanoparticles by Ion Exchanging and Study on Their dispersion stability

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Journal of Wuhan University of Technology(Materials Science) 2004年第2期19卷 7-10页

作者：黄可知 Wuhan University of Technology

By adopting sodium silicate as a major material,SiO_2 nanoparticles (size in 8-15nm) water-dispersiod was prepared by ion *** effects of sodium silicate concentration,surface-modifying time,temperature and technological conditions on their diameter,size distribution and dispersion stability were also *** result show that,the hydrophilic lipophlic and hydrophilic-lipophilic SiO_(2) nanoparticles water-dispersoid can be prepared through different kinds of surface-modifiers and the optimum reaction conditions have been determined as follows:sodium silicate solution concentration:8w%;silicone dosage:3% of the total mass of nano SiO_(2) water-dispersoid;adding way and time of surface-modifier:continual dropping for 2h;surface-modifying temperature:60-70℃.

关键词： nanoparticles ion exchanging surface-modified size distribution dispersion stability

Beneficial effects of high-pressure homogenization on the dispersion stability of aqueous hydrolysate from Mytilus edulis

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Food Science and Human Wellness 2020年第4期9卷 394-401页

作者： Fengjiao Mao Maolin Tu Fengjiao Fan Chao Wu Cuiping Yu Ming Du School of Food Science and Technology National Engineering Research Center of SeafoodDalian Polytechnic UniversityDalian 116034China College of Food Science and Engineering Nanjing University of Finance and EconomicsNanjing 210023China

Owing to the formation of aggregation and gelation during storage,certain proteins and peptides exhibit limited applications in aqueous protein food *** purpose of this study was to investigate the influence of homogenization and xanthan gum addition on the dispersion stability of Mytilus edulis hydrolysate(PHM).High-pressure homogenization(HPH)at 360 and 40 bar in the first and second values,respectively,and adding xanthan gum at a concentration of 1 mg/mL showed significantly improvement on the stability of the PHM ***-xanthan gum solutions(PHMX)showed the highest polypeptide precipitation rate and turbidity retention rate compared with those of ***,the centrifugal precipitation rate of PHMX without HPH was higher than that of homogeneous *** HPH treatment at 400 bar,the percentage of smaller particles in PHM and PHMX was increased,the aqueous system became more uniform,and the fluorescence intensity reached its *** pretreatment improved the polypeptide dispersion stability and turbidity retention rate of PHM and PHMX and reduced the fluorescence *** interactions of xanthan gum and polypeptide render the network microstructure more uniform under the conditions of homogenization,thus improving the dispersion stability of PHMX ***,under the premise of adding xanthan gum,HPH can better enhance the dispersion stability of the polypeptide in PHM.

关键词： Mytilus edulis Polypeptide Xanthan gum Homogenized mixed system dispersion stability

An IR Study of the dispersion stability of Catalyst Powders Dispersed in Solutions of Linear Saturated Polyesters

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Chemical Research in Chinese Universities 1992年第1期8卷 59-63页

作者： Gunter R.Joppien Harald Urban Technische Hochschule Darmstadt Darmstadt F. R. GermanyTechnische Hochschule Darmstadt Darmstadt F. R. Germany

The conformation of polymers at the solid-liquid interface has been the subject of considerable interest in the fundamental theory and applied practice. In paints and printing inks, dispersions of pigment or filler powders in polymeric binder solutions have to be maintained in the colloidal state. One of the stabilizing mechanisms for paint is the steric stabilization. On the other hand, in the formation reaction of polymer at the solid-liquid interface took place between monomer solutions and solid

关键词： Infrared spectrum dispersion stability Polyester Catalyst

ZrO2/PMMA Nanocomposites： Preparation and Its dispersion in Polymer Matrix

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Chinese Journal of Chemical Engineering 2013年第2期21卷 113-120页

作者： FAN Fangqiang XIA Zhengbin LI Qingying LI Zhong CHEN Huanqin School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 China

ZrO2/PMMA nanocomposite particles are synthesized through an in-situ free radical emulsion polymerization based on the silane coupling agent （Z-6030） modified ZrO2 nanoparticles, and the morphology, size and its distribution of nanocomposite particles are investigated. Scanning electron microscopy （SEM） images demonstrate that the methyl methacrylate （MMA） feeding rate has a significant effect on the particle size and morphology. When the MMA feeding rate decreases from 0.42 ml-min-1 to 0.08 ml. min-1, large particles （about ***） will not form, and the size distribution become narrow （36-54 nm）. The average nanocomposite particles size increases from 34 nm to 55 nm, as the MMA/ZrO2 nanoparticles mass ratio increased from 4 ： 1 to 16 ： 1. Regular spherical ZrO2/PMMA nanocomposite particles are synthesized when the emulsifier OP-10 concentration is 2 mg.m1-1. The nanocomposite particles could be mixed with VAc-VeoVa10 polymer matrix just by magnetic stirring to prepare the ZrOE/PMMA/VAc-VeoVal0 hybrid coatings. SEM and atomic force microscopy （AFM） photos reveal that the distribution of the ZrO2/PMMA nanocomposite particles in the VAc-VeoVal0 polymer matrix is homogenous and stable. Here, the grafted-PMMA polymer on ZrO2 nanoparticles plays as a bridge which effectively connects the ZrO2 nanoparticles and the VAc-VeoVal0 polymer matrix with improved comparability. In consequence, the hybrid coating with good dispersion stability is obtained.

关键词： ZrO2 nanoparticles core-shell structure monomer feeding rate dispersion stability

Nanolubricant additives: A review

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Friction 2021年第5期9卷 891-917页

作者： Jun ZHAO Yiyao HUANG Yongyong HE Yijun SHI College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Division of Machine Elements LuleåUniversity of TechnologyLuleå97187Sweden

Using nanoadditives in lubricants is one of the most effective ways to control friction and wear,which is of great significance for energy conservation,emission reduction,and environmental *** the scientific and technological development,great advances have been made in nanolubricant additives in the scientific research and industrial *** review summarizes the categories of nanolubricant additives and illustrates the tribological properties of these *** on the component elements of nanomaterials,nanolubricant additives can be divided into three types:nanometal-based,nanocarbon-based,and nanocomposite-based *** dispersion stabilities of additives in lubricants are also discussed in the review *** affecting factors and effective dispersion methods have been investigated in ***,the review summarizes the lubrication mechanisms of nanolubricant additives including tribofilm formation,micro-bearing effect,self-repair performance,and synergistic *** addition,the challenges and prospects of nanolubricant additives are proposed,which guides the design and synthesis of novel additives with significant lubrication and antiwear properties in the future.

关键词： nanolubricant additive dispersion stability tribological properties lubrication mechanism

Performance of Polyaniline-coated Short Carbon Fibers in Electromagnetic Shielding Coating

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Journal of Materials Science & Technology 2007年第4期23卷 529-534页

作者： Dongxiu YU Jiang CHENG Zhuoru YANG School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 China

Combined nitric acid oxidation method and polyaniline （PANI）-coated method were applied to modify the surface properties of short carbon fibers （SCF）. The electrical and mechanical properties of acrylic coatings with 50 wt pct PANI-coated carbon fiber were investigated by using scanning electron microscope （SEM）, UV-Vis spectrophotometer, four-probe method and the coaxial cable method. The results of the pH measurement and XPS （X-ray photoelectron spectroscopy） patterns showed that the oxygen functional groups, such as -OH and -COOH, were attached on the carbon fiber surfaces after oxidation treatment. The XPS analysis of PANl-coated oxidized SCF （PAOSCF） revealed that PANI may bond on the surface of oxidized SCF with chemical bonds. SEM images and surface roughness analyses showed that PANl-coated layer changed the surface morphology. Compared with SCF/acrylic coating, the surface resistivity of PAOSCF/acrylic coating decreased from17.1 to 5.3 Ω/sq and the shielding efficiency （SE） value increased from 1.54 to 23.3 dB.

关键词： Carbon fibers Polyaniline Surface treatment dispersion stability Shielding effectiveness

Surface-functionalized cellulose nanocrystals(CNC)and synergisms with surfactant for enhanced oil recovery in low-permeability reservoirs

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Petroleum Science 2023年第3期20卷 1572-1583页

作者： Zhe Li Wan-Li Kang Meng-Lan Li Hong-Bin Yang Tong-Yu Zhu Ying-Qi He Hai-Zhuang jang Bo-Bo Zhou Ji-Ting Hao Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Ministry of EducationQingdao266580ShandongPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China

Nanocellulose,a natural polymeric nanomaterial,has attracted significant attention in enhanced oil recovery(EOR)applications due to its abundance,nanoscale,high oil-water interfacial adsorption *** this study,surface-functionalized cellulose nanocrystals(SF-CNCs)were prepared via hy-drochloric acid hydrolysis and chemical modification,with adaptable nanosize and considerable dispersion stability in low-permeability *** SF-CNCs were structurally characterized by FT-IR,Cryo-TEM,which have a diameter of 5-10 nm and a length of 100-200 *** SF-CNC dispersions possessed higher stability and stronger salt-tolerance than those of corresponding CNC dispersions,due to the strong hydrophilicity of the sulfonic acid *** was synergistically used with a non-ionic surfactant(APG1214)to formulate a combined flooding system(0.1 wt%SF-CNC+0.2 wt%APG1214).The combined flooding system exhibits strong emulsification stability,low oil-water interfacial tension of o.03 mN/m,and the ability to alter the wettability for oil-wetting ***,the combined system was_able to provide an optimum EOR efficiency of 20.2%in low-permeability cores with 30.13×10^(-3)μm^(2).*** can enlarge the sweep volume and increase the displacement efficiency ***,the newly formulated nanocellulose/surfactant combined system exhibits a remarkable EoR performance in low-permeability reservoirs.

关键词： Low-permeability reservoirs Enhanced oil recovery Cellulose nanocrystals(CNC) Surfactant dispersion stability

Influence factors on thermal conductivity of ammonia-water nanofluids

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Journal of Central South University 2012年第6期19卷 1622-1628页

作者：杨柳杜垲张小松 School of Energy and Environment Southeast University

In order to investigate the mechanism of nanoparticles enhancing the heat and mass transfer of the ammonia-water absorption process,several types of binary nanofluids were prepared by mixing Al2O3 nanoparticles with polyacrylic acid(PAA),TiO2 with polyethylene glycol(PEG 1000),and TiN,SiC,hydroxyapatite(noodle-like) with PEG 10000 to ammonia-water solution,*** thermal conductivities were measured by using a KD2 Pro thermal properties *** influences of surfactant and ammonia on the dispersion stabilities of the binary nanofluids were investigated by the light absorbency ratio index *** results show that the type,content and size of nanoparticles,the temperature as well as the dispersion stability are the key parameters that affect the thermal conductivity of *** the given nanoparticle material and the base fluid,the thermal conductivity ratio of the nanofluid to the ammonia-water liquid increases as the nanoparticle content and the temperature are increased,and the diameter of nanoparticle is ***,the thermal conductivity ratio increases significantly by improving the stabilities of nanofluids,which is achieved by adding surfactants or performing the proper ammonia content in the fluid.

关键词： binary nanofluids ammonia-water thermal conductivity size effect dispersion stability