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Application of annexation principle to the study of thermodynamic properties of Ag-Bi-In metallic melts

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Journal of university of science and technology Beijing 2003年第1期10卷 18-20页

作者： Jian ZhangMetallurgy school, university of science and technology Beijing, Beijing 100083, china Metallurgy school University of Science and Technology Beijing Beijing 100083 China

Based on the measured activities, the phase diagrams and the annexation principle, the calculating models of mass action concentrations for Ag-Bi and Ag-Bi-In melts have been formulated. The calculated results agree with practice and obey the mass action law, showing that the models formulated can reflect the structural characteristics of both melts. Meanwhile, it confirms that annexation principle is applicable to the Ag-Bi-In metallic melts. The melts involving eulectic which give rise to phase separation, and in which activities exhibit positive deviation from Raoult's law is the basic cause of melts transforming from homogeneous to heterogeneous ones.

关键词： the mass action law annexation principle two phase melts activity, mass action concentration

Calculating model of mass action concentrations for Ag-Au-Cu melts

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Rare Metals 2002年第1期21卷 43-47页

作者： ZHANG Jian Metallurgy school, university of science and technology Beijing, Beijing 100083, china Metallurgy school University of Science and Technology Beijing 北京 100083

Based on phase diagrams and measured activities, the calculatingmodel of mass action concentrations for het- erogeneous meltsAg-Au-Cu was formulated. Calculated results agree with the improvedresults of recent research work, Showing that the model formulatedcan reflect the structural characteristics of these melts. In thismodel, without the help Of any empirical parameters, only threeequilibrium constants are used, hence it is simple, lear, andfavorable to the sim- Plification of calculation.

关键词： activity mass action concentration eutectic Solid solution

Application of the annexation principle to the study of thermodynamic properties of ternary metallic melts In-Pb-Ag and In-Bi-Sb

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Rare Metals 2002年第2期21卷 142-151页

作者： ZHANG JianMetallurgical Engineering school.university of science and technology Beijing, Beijing 100083, china Metallurgical Engineering school University of Science and Technology Beijing 北京 100083

Based on the phase diagrams, measured activities an the annexationprinciple, the calculating models of mass action concentrations forin-Pb-Ag and In-Bi-Sb ternary metallic melts have been *** results of calculation both agree with practice, and obey the lawof mass action, showing that the models formulated can reflect thestructural reality of the corresponding melts and the annexationprinciple is applicable to the them.

关键词： activity mass action concnetration th annexation principle In-PB-Ag

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

Nonclassical Plane-crystallographic Groups and Their Applications IV

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 228-232页

作者： Lequan Min Xaodan zhang(Applied science school, school,university of science and technology Beijing, Beijing 100083,china) Applied science school University of Science and Technology Beijing Beijing 100083 China

Eight kinds of nonclasslcal periodic lattices with locally 8-fold rotational symmetries are *** can be described via nonclassical Planc-crystallographic groups. The periodic lattices may be interpreted bythe projections on the plane of the corresponding unit cells consisting of embedding polyhedrons, respectively. TheFourier-transform patterns of the Periodic lattices have striking approximate'8-fold rotational symmetries', some ofwhich are similar to those displaying in the electrton-diffraction patterns of so-called quasicrystals.

关键词： nonclasslcal crystallographic groups locoally 8-fold symmetry Fourier-transform patterns, quasicrystals

Manufacture of the Ultrafine Grain WC/Co Cemented Carbides by Combined Sintering Processing

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 208-213页

作者： Binghai Liu Yue Zhang Shixi Ouyang Qikai Li(Institute of Technical Physics and Chemistry, east china university of science and technology , shanghai 20023., china)(Material science and Engineering school. university of science and technology Beijing, Beijing 100083, china)(State Key Laboratory for Synthesis and Processing of Advanced Materials. Wuhan university of science and technology, Wuhan 430070, china,) E china Univ Sci & Technol Inst Tech Phys & Chem Shanghai 200237 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Wuhan Univ Sci & Technol State Key Lab Synth & Proc Adv Mat Wuhan 430070 Peoples R China

A new kind of sintering process, combined sintering process. i.e. vacuum sintering plus hot isolate pressure sintering (HIP), was introduced for producing ultrafine WC-10% Co (mass fraction. so as the follows) cemented carbides. The effects of some processing parameters on the microstructure and mechanical properties of the obtained cemented carbides were studied. The results show that the rapid shrinkage and the pronounced densification of tile cemented carbides took place during the vacuum sintering stage, which is intinaately correlated with the local liquid sintering occurred during this earl} sintering stage for the high surface activity of ultrafine WC-Co powder. The way of high pressure imposing. isothermal treatment cycle during *** sintering and HIP sintering stage directly influence the densitication of compacts and the mechanical properties of the produced WC-10%Co cemented carbides.

关键词： ultrafine WC-Co cemented carbides vacuum sintering HIP sintering

Syntheses of amphiphilic biodegradable copolymers of poly(ethyl ethylene phosphate) and poly(3-hydroxybutyrate) for drug delivery

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science china Chemistry 2009年第7期52卷 961-968页

作者： CHENG Jing1 & WANG Jun2 1 Department of Polymer science and Engineering, university of science and technology of china, Hefei 230026, china 2 Hefei National Laboratory for Physical sciences at Microscale, school of Life sciences, university of science and technology of china, Hefei 230027, china Department of Polymer science and Engineering University of Science and Technology of China Hefei 230026 China Hefei National Laboratory for Physical sciences at Microscale School of Life Sciences University of Science and Technology of China Hefei 230027 China

Biodegradable and amphiphilic triblock copolymers poly(ethyl ethylene phosphate)-poly(3-hydroxybutyrate)-poly(ethyl ethylene phosphate) (PEEP-b-PHB-b-PEEP) have been successfully synthesized through ring-opening polymerization. The structures are confirmed by gel permeation chromatography and NMR analyses. Crystallization investigated by X-ray diffraction reveals that the block copolymer with higher content of poly(ethyl ethylene phosphate) (PEEP) is more amorphous, showing decreased crystallizability. The obtained copolymers self-assemble into biodegradable nanoparticles with a coreshell micellar structure in aqueous solution, verified by the probe-based fluorescence measurements and transmission electronic microscopy (TEM) observation. The hydrophobic poly(3-hydroxybutyrate) (PHB) block serves as the core of the micelles and the micelles are stabilized by the hydrophilic PEEP block. The size and size distribution are related to the compositions of the copolymers. Paclitaxel (PTX) has been encapsulated into the micelles as a model drug and a sustained drug release from the micelles is observed. MTT assay also demonstrates that the block copolymers are biocompatible, rendering these copolymers attractive for drug delivery.

关键词： poly(3-hydroxybutyrate) polyphosphoester drug delivery polymeric nanoparticles

Numerical simulations and experimental investigations on transverse effects of two-wave mixing in a photovoltaic photorefractive crystal

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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 856-863页

作者： CAI Xin1,2,LIU JinSong1 & WANG ShengLie1 1 Wuhan National Laboratory for Optoelectronics,school of Optoelectronic science and Engineering,Huazhong university of science and technology,Wuhan 430074,china 2 school of science,Wuhan university of technology,Wuhan 430070,china 1. Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China2. School of Science Wuhan University of Technology Wuhan 430070 China

The transverse effects of two Gauss waves mixing in a photovoltaic photorefractive crystal,i.e.,the dynamical evolutions of signal beam with different parameters,are traced numerically and *** the one-dimensional numerical simulations and two-dimensional experimental investigations show that the self-focusing effect of signal beam becomes more obvious as the intensity of pump beam and the angle between the signal and pump beams *** accordance with these results,the state of two Gaussian waves mixing is controllable.

关键词： numerical simulation experimental investigation two-wave mixing transverse effects Gaussian distribution

Microstructural Features During Strain Induced Ferrite Transformation in 08 and 20Mn Steels

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Journal of university of science and technology Beijing 2001年第2期8卷 105-110页

作者： Ping Yang, Feng-e Cui, Fuming Wang (Materials science and Engineering school, university of science and technology Beijing, Beijing 100083, china) (Metallurgy school, university of science and technology Beijing, Beijing 100083, china) Univ Sci & Technol Beijing Mat Sci & Engn Sch Beijing 100083 Peoples R China Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China

The microstructure evolution during strain induced ferrite transformation was followed in thermal-simulation tests of clean 08 and 20Mn steels. The influences of carbon equivalence and initial austenite grain size on ferrite grain refinement and the volume fraction of ferrite during straining were inspected. The results revealed that the accelerating effect of ferrite transformation by strain was increased as the carbon equivalence decreased. However, finer ferrite grains were obtained at higher carbon content. At strain of similar to1.5 ferrite grains less than 3 mum and 2 mum can be obtained in 08 and 20Mn steels respectively. Whereas the ferrite grain refinement in 08 steel was due to both effects of strain induced transformation and ferrite dynamic recrystallization, that in 20Mn was mainly due to strain induced transformation. Heavy strain can produce fine ferrite grains in coarse austenite grained 08 steel, but it would lead to band microstructure in coarse austenite grained 20Mn.

关键词： clean carbon steel strain induced transformation grain refinement ferrite dynamic recrystallization