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The Role of Surfactant and Costabilizer in Controlling Size of Nanocapsules Containing TEGDMA in Miniemulsion

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Journal of wuhan University of technology({2.s {3.) 2009年第6期24卷 1004-1006页

作者：郭进新黄翠 School and Hospital of Stomatology Wuhan University Key Laboratory of Oral Biomedical Engineering of Ministry of Education Wuhan University

Nanocapsules with triethylene glycol dimethacrylate （TEGDMA） as core material and polyurethane as wall material used for self-healing bonding resin were prepared by interfacial polycondensation in miniemulsion. The influence of surfactant and costabilizer conc{2.ration on nanocapsules size and stability of nanocapsules was investigated. The size and its polydispersity of the nanocapsules were measured by light-scattering particle size analyzer. When the conc{2.ration of SDS were increased from 2.5wt% to 10wt%,the size decreases from 3.0.5 nm to 2.8.3.nm, PDI decreased from 0.2.0 to 0.111. As the conc{2.ration of HD increased, the size and PDI were both decreased, When reaching 10wt%,the size was 2.8.0 nm,PDI was 0.13.. SDS and HD play important effect in synthesis of Nanocapsules containing *** changing the surfactant and costabilizer conc{2.ration it was possible to synthesize a wide variety of nanocapsules sizes. The performance and technical parameters of nanocapsules had been researched preliminarily, which built the solid foundation for the application to the self-repairing bonding resin.

关键词： triethylene glycol dimethacrylate nanocapsules interfacial polycondensation miniemulsion

Effects of NaNbO_3.Co_2._3.Co-additive on the Properties of PZN-PZT Ceramics

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Journal of wuhan University of technology({2.s {3.) 2007年第4期22卷 722-724页

作者：邓毅华 College of material science and Engineering South China University of Technology Department of Electronic science and {2. Huazhong University of Science and TechnologyWuhan 430074China

NaNbO3.Co2.3.co-added PZN-PZT （PZCNNT） ceramics were prepared using conv{2.ional solid state reaction. The piezoelectric and dielectric properties were measured. The experim{2.al results show that the addition of 0.3.o1% Co2.3.leads to low dielectric loss （tgδ） in PZCNNT ceramics and the proper addition of NaNbO3.not only improves piezoelectric properties but also decreases intensively dielectric loss and mechanical loss. The optimal ceramic having d3.=3.0 pC/N, kp=0.59, εr=985, tgδ=0.003., Qm=13.0 was obtained.

关键词： PZN-PZT piezoelectric constant dielectric constant dielectric loss

Surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

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Progress in Natural science:materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2. FENG Zhijing1 and CHENG Kai3.1. State Key Laboratory of Tribiology, Tsinghua University, Beijing 100084, China 2. Departm{2. of material {3.s, Changchun University of {3. and technology, Changchun 13.02., China 3. Faculty of Information and Engineering Systems, City Campus, Leeds LS1 3.E, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China Department of material {2.s Changchun University of Science and Technology Changchun 130021 China Faculty of Information and Engineering Systems City Campus Leeds LS1 3HE UK

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose {2. machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.2. nm root mean square (RMS) after 2. min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

Separation of Red (Y_2._3. Eu^(3.)), Blue (Sr,Ca,Ba)_(10)(PO_4)_6Cl_2. Eu^(2.) and Green (LaPO_4:Tb^(3.),Ce^(3.)) Rare Earth Phosphors by Liquid/Liquid Extraction

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Journal of wuhan University of technology({2.s {3.) 2009年第3期24卷 418-423页

作者：梅光军 School of Resource and Environmental Engineering Wuhan University of Technology

A novel process for separation of red （Y2.3. Eu^3.）, blue （Sr, Ca, Ba）10（PO4）6Cl2. Eu^2. and green （LaPO4： Tb^3., Ce^3.） fine tricolor phosphor powders was established. First, the green phosphor was extracted and separated from three phosphor mixtures in heptane/DMF（N, N-Dimethylformamide） system using stearylamine or laurylamine （DDA） as the cationic surfactant. Then, after being treated with 99.5% ethanol, the blue and red phosphors could be separated in Heptane/DMF system in presence of 1-octanesulfonic acid sodium salt as the anionic surfactant. Satisfactory separation results have been achieved through two steps extractions with their artificial mixtures. The grades and recovery of separated products reached respectively as follows： red product was 95.3. and 90.9%, blue product was 90.0% and 95.2., and green product was 92.2. and 91.8%.

关键词： rare earth phosphor liquid-liquid extraction separation

Structure and Properties of TiB_2.Thin Films Deposited at Low Temperatures Using RF Magnetron Sputtering

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Journal of wuhan University of technology({2.s {3.) 2008年第5期23卷 666-669页

作者：戴伟张同俊 State Key Lab of material Processing and Die & Mould technology Huazhong University of Science and Technology

The TiB2.thin films were deposited on steel substrates using RF magnetron sputtering technique with the low normalized substrate temperature （0.1〈Ts/Tm〈0.2.. Microstructure of these films was obtained by field emission scanning electron microscope （FESEM） and the grazing incidence X-ray diffraction （GIXRD） characterization, while the composition of films was obtained using Auger emission spectroscopy （AES） analysis. It was found that the TiB2.thin films were overstoichiometric with the B/Ti ratio at 2.3. and the diffusion of Ti and B atoms on the substrate surface was greatly improved at 3.0 ℃. Moreover, a new dense structure, named ＂equiaxed＂ grain structure was observed by FESEM at this substrate temperature, Combined with FESEM and AES analysis, it was suggested that the ＂equiaxed＂ grain structure was located in Zone 2.at the normalized substrate temperature as low as 0.18.

关键词： TiB2.thin films structure zones 1,2.T equiaxed structure superhard coating auger electron spectroscopy

Numerical Simulation of Rock Fracturing under Uniaxial Compression Using Virtual Internal Bond Model

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Journal of Shanghai Jiaotong university(science) 2009年第4期14卷 423-428页

作者：柯长仁蒋俊玲葛修润 School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University School of Civil Engineering Hubei University of Technology Institute of Rock and Soil Mechanics The Chinese Academy of Science

A multi-scale virtual internal bond (VIB) model for the isotropic materials has been recently proposed to describe the material deformation and fracturing. During the simulation process of material fracturing using VIB, the fracture criterion is directly built into the constitutive formulation of the material using the cohesive force law. Enlightened by the similarity of the damage constitutive model of rock under uniaxial compression and the cohesive force law of VIB, a VIB density function of rock under uniaxial compression is suggested. The elastic modulus tensor is formulated on the basis of the density function. Thus the complete deformation process of rock under the uniaxial compression is simulated.

关键词： virtual internal bond rock uniaxial compression stress-strain curve

Influence of Molecular Weight of PEO on Performance of Quasi-solid-state Dye-sensitized Solar Cells

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Journal of wuhan University of technology({2.s {3.) 2010年第2期25卷 218-222页

作者：沈小林 School of materials science & Engineering Xi’an Jiaotong University

Quasi-solid-state dye-sensitized solar cells （DSCs） were prepared using gel electrolyte gelated by poly（ethylene-oxide）（PEO） with different molecular weight. With the increase in PEO molecular weight, the short circuit current densities （Jsc） increase significantly, which is related to the increase in I - diffusion due to the increase in free volume of gel electrolyte. However, only a slight increase in open voltage （Voc） is observed, which is explained by the decrease in dark current arising from the reduction of triiodide （I3.-） by conduction band electrons.

关键词： dye-sensitized solar cell poly(ethylene oxide) gel electrolyte molecular weight

Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

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Progress in Natural science:materials International 2005年第5期15卷 453-457页

作者： LI Chensha1*, WANG Dazhi1, ZHANG Baoyou2. WANG Xiaofeng1, CAO Maosheng3. and LIANG Ji1(1. Department of Mechanical Engineering, Tsinghua University, Beijing 100084, Ch{2. 2. Center for Analysis and Measurement, Harbin Institute of technology, Harbin 150001, Ch{2. 3. School of material science and Engineering, Tsinghua University, Beijing 100084, Ch{2.) Department of Mechanical Engineering Tsinghua University Beijing 100084 China Center for Analysis and Measurement Harbin Institute of Technology Harbin 150001 China School of material science and Engineering Tsinghua University Beijing 100084 China

Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carbon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

关键词： carbon nanotubes electric double-layer capacitors phenolic resin polytetrafluoroethylene.

Separation of Red (Y_2._3.Eu^(3.)), Blue (BaMgAl_(10)O_(17):Eu^(2.)) and Green (CeMgAl_(10)O_(17):Tb^3. Rare Earth Phosphors by Liquid/Liquid Extraction

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Journal of wuhan University of technology({2.s {3.) 2009年第4期24卷 603-607页

作者：梅光军 School of Resource and Environmental Engineering Wuhan University of Technology

A novel process for separation of red （Y2.3.Eu^3.）, blue（BaMgAl10O17：Eu^2.） and green （CeMgAl10O17：Tb^3. rare earth fluorescent powders was proposed. At first, the blue powder can be extracted selectively from an aqueous solution using a chelating collector 2.thenoyltrifluoroacetone （TTA） dissolved in heptane at alkaline pH condition, then, chloroform was used for extracting the green powder into organic phase. The red phosphor remains in aqueous phase with potassium sodium tartrate depressant （PST）. Therefore, three phosphors can be separated successfully from their artificial mixtures by liquid/liquid extraction, and grades and recovery of separated products reach respectively as follows： red is 96.9% and 95.2., blue is 82.7% and 98.8%, green is 94.6% and 82.6%.

关键词： rare earth phosphor solid-solid separation liquid/liquid extraction