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Precision bending of high-quality components for volume applications T. WELO, F. WIDER?E Department of Engineering Design and Materials, Norwegian University of Science and Technology... cross-sectional deformations such as suck-in and volume conservation effects, along with global deformations such as springback. An analytical model was developed to determine the particular......
(1) (2) 式中:αl和αv分别为液相和气相的体积分数;ρl和ρv分别为液相和气相的密度;和分别为液相和气相的速度;和分别为液相和气相的质量分数源相;和分别为液相和气相间的质量传递. 动量方程: (3) 式中:ρ和分别为两相混合的密度和速度;为体积力;μ为黏性系数. 能量方程: (4) 式中:keff为有效热导率;Sh为能量源相. 1.3 边界条件及算法设置 本文采用的工质为R134a,工作压力为5.7×105 Pa,对应的饱和温度为20 ℃,并采用R134a的物性参数为定值,如表1所示.本文中R134a的物性参数查阅自美国国家标准技术研究所(NIST)研发的工质物性参数计算软件REFP......
the isoperibol reaction calorimetry. ΔrHm was calculated by a designed thermochemical cycle of the coordination reaction. From the results and other auxiliary quantities, the standard molar enthalpy of formation of [La2(β-ala)6*(H2O)4](ClO4)6*H2O is obtained to be ΔfHm°{[La2(β-ala)6*(H2O)4](ClO4)6*H2O} = - 7062.911 kJ*mol-1. Key words:rare earths; β-Alanine; thermochemistry; standard molar enthalpy......
studied by analysing the electrical resistance variation of the solution Cu-Ni-Si alloy in the process of aging. Due to the linear relationship between electrical conductivity and volume fraction... transformation were established. 关键词:CuNiSi alloy; aging; resistivity; volume fraction; transformation kinetics; [全文内容正在添加中] ......
Influence of the Cd/S Molar Ratio on the Optical and Structural Properties of Nanocrystalline CdS Thin FilmsM.Thambidurai1,N.Murugan2,N.Muthukumarasamy1,S.Agilan1,S.Vasantha1,R.Balasundaraprabhu331... films prepared using cadmium to thiourea molar ratio of0.3:0.3 indicate the formation of nanocrystalline CdS with grain size of 5 nm.Fourier transform infrared (FTIR)analysis shows the absorption......
Effect of Fuel to Oxidant Molar Ratio on Structural and DC Electrical Conductivity of ZnO Nanoparticles Prepared by Simple Solution Combustion MethodC.S.Naveen,M.L.Dinesha,H.S.Jayanna摘 要:ZnO nanoparticles of different sizes were prepared by varying the molar ratio of glycine and zinc nitrate hexahydrate as fuel and oxidizer(0.1,0.8,1.11,1.3,1.5,1.7,2.0......
Effect of volume fraction on microstructure and mechanical properties of Si3N4/Al compositesXIU Zi-yang, CHEN Guo-qin, WU Gao-hui, YANG Wen-shu, LIU Yan-mei(School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China)Abstract:Si3N4 particles reinforced aluminium matrix composites (Si3N4/Al) with different particle volume fractions (45%, 50%, and 55%) were......
Strain rate sensitivity and activation volume of electrodeposited nanocrystalline Ni and Ni-Co alloysLIAN Jianshe,GU Changdong,LI Guangyu,and JIANG Qing Key Laboratory of Automobile Materials... of the electrodeposited 40 nm grain sized Ni,25 nm Ni-1.7 wt.%Co,and 13 nm Ni-8.6 wt.%Co alloys at various strain rates and room temperature were reviewed with emphasis on strain rate sensitivity and activation volume......
Influence of the Aggregate Volume on the Electrical Resistivity and Properties of Portland Cement Concretes魏小胜1,肖莲珍21. School of Civil Engineering and Mechanics,Huazhong University of Science and Technology2. School of Materials Science and Engineering,Wuhan Institute of Technology摘 要:The electrical resistivity of concretes with various aggregate volume......
Mechanism of Calcined Phosphogypsum for the Volume Change of Blended Cement杨志明摘 要:<正>The paper describes an investigation into the volume change... the function of decreasing volume shrinkage to blended cement possessing steel slag and high calcium ash. In sulfate curing, calcined phosphogypsum can avoid the phenomenon of protrude apex of the blended......