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Kinetics analysis of volume phase transition of intelligent neutral thermo-sensitive hydrogels

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Science China(Physics,Mechanics & Astronomy) 2008年第5期51卷 532-540页

作者： WANG XiaoGui1 & LI YiQuan2 1 college of mechanical engineering,Zhejiang {3. of technology,Hangzhou 3.003.,China 2 School of mechanical & Electronic engineering,Changchun {3. of Science and technology,Changchun 13.022,China 1. college of mechanical engineering Zhejiang University of Technology Hangzhou 310032 China 2. School of mechanical & Electronic engineering Changchun University of Science and Technology Changchun 130022 China

In this work,utilizing the first law of thermodynamics and the Flory mean-field theory,the kinetic deformation studies concerning the volume phase transition of the neutral thermo-sensitive hydrogels were performed *** hydrogel was assumed as a biphasic mixture medium in the framework of the continuum mixture *** the energy conservation of the thermodynamics system of the hydrogel,the governing equations for the kinetics of the nonlinear large deforma-tion were *** explicit analytical expressions of the effective stress tensor and the chemical potential of the fluid of the thermo-sensitive hydrogel PNIPA were also obtained from the Helmholtz free energy,which can model the steady-static volume phase transition quantitatively.

关键词： thermo-sensitive hydrogel volume phase transition effective stress energy conservation

Morphological Evolution of Nb_2O_5 in a Solvothermal Reaction: From Nb_2O_5 Grains to Nb_2O_5 Nanorods and Hexagonal Nb_2O_5 Nanoplatelets

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Journal of Wuhan university of technology(Materials Science) 2009年第2期24卷 245-248页

作者：胡卫兵 School of Chemical and Environmental engineering Hubei Institute for Nationalities Department of Physics Huazhong University of Science and Technology

Novel Nb2O5 nanorods and polygonal Nb2O5 platelets were generated by a simple solvothermal technique. The geometry evolution of the resultant Nb2O5 from amorphous nanoparticles to crystallized particles, from polygonal platelets to well-elongated nanorods was been studied in detail. The processing parameters, including the reaction temperature, reaction time, concentration of the precursors, and pH value of the solution, which affect the shape and size of the nanorods, were investigated. The Nb2O5 nanorods with different aspect ratios were examined by XRD, SEM and TEM. The experimental results show that Nb2O5 nanorod is the orthorhombic structure and well-crystallized. The growth of the nanorods follows their [001] direction. The successful generation of high quality Nb2O5 nanorods is not only important for transition metal oxide research, but also potentially important for further formation of new Nb-based 1-D nanostructures, such as NbS2 and NbN.

关键词： solvothermal morphological evolution Nb2O5 nanomateraials

Matching Strategies and Fuzzy URLs in Web Based Component Retrieving

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Wuhan university Journal of Natural Sciences 2001年第Z1期6卷 283-287页

作者： Wang Ying 1,2 , Sang Da yong 2, 3.1. college of Management, Xi’an Jiaotong university, Xi’an 710049,China 2.college of {3., Air Force university of {3., Xi’an 71003.,China 3. State Key Laboratory of Software {3., Wu college of Management Xi’an Jiaotong University Xi’an China college of engineering Air Force University of Engineering Xi’an China State Key Laboratory of Software engineering Wuhan University Wuhan China

The World Wide Web (WWW) has greatly changed the way of component based software reuse, for large number of components provided by different vendors become available and it's rather difficult to find and choose what we in fact need. To make large amount of the components collaborate, an information exchanging model is essential. In order to retrieve and search the suitable or usable components more effectively, some techniques should be taken into account. Among these techniques, matching strategies and fuzzy URL semantics are significant for the former help us to find components which could be reused and the other both to broaden the searching areas and use some uncertain information to make the searching more purposive. A brief discuss on an abstract component model (UACModel) is begun, which was proposed to promote the interoperability and information exchange among various reusable component libraries (RCLs), and a framework for component retrieval. Then the emphases are put on some matching strategies, especially incomplete ones that encourage reuse through component customization, and fuzzy URL extensions to be supported and realized.

关键词： component reuse interoperability model component retrieval index repository reusable component library (RCL)

Electrical Breakdown Characteristic of Nanostructured W-Cu Contacts Materials

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Journal of Wuhan university of technology(Materials Science) 2006年第4期21卷 32-35页

作者：王俊勃 School of mechanical and Electrical engineering Xi'an Polytechnic UniversityXi'an 710048 ChinaSchool of Science Xi'an Jiaotong University Xi'an 710049China

Nanostructured （ NS ）W-Cu composite powder was prepared by mechanical alloying （ MA ）, and nanostructared bulk of W-Cu contact material was fabricated by hot press sintering in an electrical vacuum furnace. The rnicrostructure, electric conductivity, hardness and break down voltage of NS W- Cu alloys were measured and compared to those of conventional W-Cu alloys prepared by powder metallurg＇y. The experimental results show that microstructural refinement and uniformity can improve the breakdown behavior and the electric arc stability of nanostructared W- Cu contacts materials. Also, the wanostructured W- Cu contact material shows the characteristic of spreading electric arcs, which is of benefit to electric arc erosion.

关键词： nanostructured materials W-Cu alloy electrical breakdown

The band structures of BSb and B_xGa_(1-x)Sb alloys

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Science China(Physics,Mechanics & Astronomy) 2009年第6期52卷 843-847页

作者： XIONG DePing1, ZHOU ShouLi2, WANG Qi3. LUO Li1, HUANG YongQing3.& REN XiaoMin3.1 School of Physics and Optoelectronic engineering, Guangdong university of technology, {3. 510006, China 2 college of Information engineering, Zhejiang university of technology, Hangzhou 3.003., China 3.Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education, Beijing university of Posts and Telecommunications, Beijing 100876, China 1. School of Physics and Optoelectronic engineering Guangdong University of Technology Guangzhou 510006 China 2. college of Information engineering Zhejiang University of Technology Hangzhou 310032 China 3. Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

The band structures of BSb and BxGa1-xSb alloys are studied using first-principles calculations in the generalized gradient approximation. By SQS-8 supercells to model a random alloy, the direct transition energy-gap (Γ15v- Γ1c) bowing of 3.0 eV is obtained for BxGa1-xSb alloys in x = 0-50%, in x = 0-11% the energy-gap is the band-gap and increases by 7 meV/%B with boron composition increasing; by SQS-16 supercells the bowing parameter is about 1.9 eV in x = 0-12.5%. The formation enthalpies of mixing, ΔH, are calculated for BxGa1-xAs and BxGa1-xSb alloys. A comparison of enthalpies indicates that BxGa1-xSb films with boron composition of 7% may be possible.

关键词： band-gap bowing parameter boride alloys

Approximation of dense-n/2-subgraph and table compression problems

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Science China Mathematics 2005年第9期48卷 1223-1233页

作者： XU Dachuan~1 HAN Jiye~2 & DU Dongle~3.1. college of Applied Sciences,Beijing university of technology,Beijing 100022,China 2. Institute of Applied Mathematics,Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100080,China 3. Faculty of Administration,university of New Brunswick,P.O.Box 4400,Fredericton,NB E3. 5A3.Canada college of Applied Sciences Beijing University of Technology Beijing 100022 China Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Faculty of Administration University of New Brunswick P.O. Box 4400 Fredericton NB E3B 5A3 Canada

We develop improved approximation algorithms for two NP-hard problems: the dense-n/2-subgraph and table *** on SDP relaxation and advanced rounding techniques,we first propose 0. 5982 and 0. 5970-approximation algorithms respec- tively for the dense-n/2-subgraph problem (DSP) and the table compression problem (TCP). Then we improve these bounds to 0. 6243.and 0. 6708 respectively for DSP and TCP by adding triangle inequalities to strengthen the SDP *** results for TCP beat the 0. 5 bound of a simple greedy algorithm on this problem,and hence answer an open question of Anderson in an affirmative way.

关键词： dense-n/2-subgraph problem(DSP) table compression problem(TCP) SDP approximation ratio

New Solution to Surface Temperature of Casting Slab Measurement Based on Preceded Reflector and Multi-Wavelength

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Journal of Iron and Steel Research International 2012年第8期19卷 12-16页

作者： LIU Jun1, MA Jiao-cheng2, YANG Feng3. XIAO Hui1, RAO Li-min1 (1. School of Nuclear engineering and technology, East China Institute of technology, Fuzhou 3.4000, Jiangxi, China 2. School of {3. engineering and Automation, Northeastern university, Shenyang 110004, Liaoning, China 3. School of Civil and Environmental engineering, East China Institute of technology, Fuzhou 3.4000, Jiangxi, China) [a] School of Nuclear engineering and technology East China Institute of Technology Fuzhou 344000 Jiangxi China [b] School of mechanical engineering and Automation Northeastern University Shenyang 110004 Liaoning China [c] School of Civil and Environmental engineering East China Institute of Technology Fuzhou 344000 Jiangxi China

The surface temperature of casting slab is an important parameter in the metallurgy field. Because the surface emissivity is uncertain and also unknown, it is difficult to measure the slab surface temperature accurately. A method based on preceded reflector and multi-wavelength was put forward to deal with the difficulty in surface temperature measurement of casting slab. On the premise of preceded reflector and non-preceded reflector, the method establishes the radiation energy equations and works out the emissivity and temperature in the equations. Also, the multilayer modeling of casting slab surface and multiple reflection-absorption process modeling were built by Monte Carlo method. The temperature measuring method had been applied in the continuous casting field. In order to verify the measured result, the thermal imaging method was adopted when the slab surface emissivity was set by repeated tests. Finally, the measured and verified temperature curves keep a same tendency and the error of the values is lower than 5℃. The comparison result shows that the method can measure temperature accurately.

关键词： casting slab emissivity surface temperature preceded reflector multi-wavelength

Study on BaTiO_3.films prepared by AC power microarc oxidation

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Science China(Technological Sciences) 2009年第8期52卷 2195-2199页

作者： HUANG WenBo, LI WenFang & HAN Bing college of Material Science and engineering, south China {3. of technology, guangzhou 510640, China 1. college of Material Science and engineering South China University of Technology Guangzhou 510640 China

BaTiO3.films were prepared by microarc oxidation (MAO) with an in-house built alternating current (AC) power supply in Ba(OH)2 solution in this study. The surface morphology, combinability with the substrate and phase composition of the films were investigated by XRD, SEM and TEM. The BaTiO3.films were annealed at a temperature range of 900 to 1200℃ and phase compositions were tested thereafter. The results showed that the BaTiO3.films were mainly composed of the primitive hexagonal phase with relatively small amount of tetragonal and amorphous phases. Moreover, the amount of amorphous phase decreased with the time of annealing. The transformation of BaTiO3.from hexagonal structure to tetragonal stucture became obvious until the annealing temperature reached 1200℃. The film consisted mainly of BaTiO3.tetragonal structure with ferroelectric property. The influence of annealing on surface morphology and mechanism of phase transformation of the films were also discussed.

关键词： microarc oxidation ferroelectric film BaTiO3 annealing phase composition

Modeling and Assessment of Buoyancy-Driven Stratified Airflow in High-Space Industrial Hall

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湖南大学学报（自然科学版） 2009年第S1期36卷 19-22页

作者： WANG Han-qing1,2,CHEN Ke1,HU Jian-jun1,3.KOU Guang-xiao2,WANG Zhi-yong2(1.School of Energy Science and engineering,Central south university,Changsha,Hunan 410083.China 2.Department of Civil engineering,Hunan university of technology,Zhuzhou,Hunan 412008,China 3.School of mechanical engineering,Purdue university,West Lafayette,USA) School of Energy Science and engineering Central South University Changsha 410083 China Department of Civil engineering Hunan University of Technology Zhuzhou 412008 China School of mechanical engineering Purdue University West Lafayette United States

In industrial environment,heat sources often are contaminant sources and health threatening contaminants are mainly passive,so a detailed understanding of airflow mode can assist in work environment hygiene measurement and *** paper presented a numerical investigation of stratified airflow scenario in a high-space industrial hall with validated commercial code and experimentally acquired boundary *** upon an actually undergoing engineering project,this study investigated the performance of the buoyancy-driven displacement ventilation in a large welding hall with big components *** results have demonstrated that stratified airflow sustained by thermal buoyancy provides zoning effect in terms of clean and polluted regions except minor stagnant eddy *** competition between negative buoyant jets from displacement radial diffusers and positive buoyant plume from bulk object constitutes the complex transport characteristics under and above stratification ***,downdraft and turbulent eddy motion complicate the upper mixing zone,but the exhaust outlet plays a less important role in the whole field *** the corresponding suggestions concerning computational stability and convergence,further improvements in modelling and measurements were given.

关键词： modelling buoyancy-driven large enclosure industrial ventilation