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41.
In this paper,taking Nb-Mo alloy system as an example,the equations of concentration of characteristic atoms of alloys in BCC structure were obtained on the basis of the idea of systematic science of alloys and the number of coordination atoms.The concentrations of characteristic atoms in B2-NbMo type ordered alloys were calculated as functions of ordering degree(s) and composition xMo.When s=smax,the concentrations of characteristic atoms of stoichiometric B2-NbMo intermetallic compound are equal to that o...  相似文献   
42.
With the models of stress corrosion and pressure solution, by Yasuhara et al., two computation conditions were designed for a hypothetical nuclear waste repository in an unsaturated dual-porosity rock mass: (i) the fracture apertures are changed with the stress corrosion and pressure solution (the porosity of rock matrix is also a function of stress); (ii) the fracture apertures and the porosity of rock matrix are constants. Then the corresponding two-dimensional FEM analyses for the coupled thermohydro-mec...  相似文献   
43.
Experimental and numerical researches were conducted to investigate the cooling performance of a single row of consoles (converging slot-hole) on a large-scale flat-plate model. The results show that the coolant flow from a row of consoles shows good lateral uniformity of adiabatic effectiveness, with regions of slightly enhanced cooling occurring between the consoles. For the console cooling geometry, the interaction between coolant jet from inclined console and the mainstream flow results in reasonable vo...  相似文献   
44.
Moderate or intense low oxygen dilution(MILD)combustion plays a significant role in the mitigation of combustion-generated pollutants and greenhouse gases whilst meeting thermal efficiency needs.However,due to the lack of the fundamental knowledge on this combustion,there is a misconception that MILD combustion should be established by high preheating of the air,which has limited its application.Our research and development on this combustion has been performed for several years. We have found that the requ...  相似文献   
45.
Owing to the deficiency in early warning for high concrete dam,a formula was established to characterize the deformation behavior of high concrete dam as a whole.The early warning index of spatial deformation was calculated by low probability principle on the basis of the deformation entropy formula proposed.The steps were as follows.Firstly,the probability method was utilized to define the degree of order and degree of chaos for each survey point.Secondly,the weight distribution among the survey points was...  相似文献   
46.
SnO2 electrodes have many advantages in the degradation of toxic or bio-refractory organic wastewater,and SnO2 is a kind of anode material which has the potential to be widely used.Electrocatalytic effi-ciency and service life of Ti\SnO2 electrodes are key factors that can influence its applications.In order to enhance the electrocatalytic characteristics of Ti\SnO2 electrodes,a type of electrocatalytic electrode with nanocoating was prepared by direct current(DC)electrodeposition method and thermal oxidati...  相似文献   
47.
张海 《粘接》1993,14(5):24-26
本文介绍一种仿瓷环氧胶粘剂,该胶耐酸耐碱,可室温固化,在室温下粘接不锈钢试样,其剪切强度可达30.7MPa;而在130℃时其剪切强度为1.7MPa。可用于修复搪瓷,粘接金属和陶瓷等。  相似文献   
48.
聚碳酸酯(PC)综合性能好,其消费与生产增长举世瞩目,在世界五大通用工程塑料中占有重要地位。国内PC生产及消费量虽不大,但潜在市场不可忽视,发展与开拓工程塑料,特别是PC的应用与生产的开发,是我国化学和石化工业发展需要之一。  相似文献   
49.
Fe-Al intermetallics with remarkable high-temperatureintensity and excellent erosion,high-temperatureoxidation and sulfuration resistance are potential lowcost high-temperature structural material.ProducingFe-Al/WC composite coating by high velocity arcspraying(HVAS)on structural materials would notonly obviate the problems faced in fabrication of thesealloys into useful shapes,but also allow the effectiveuse of their outstanding high-temperature performance,which might thus promisingly mak…  相似文献   
50.
Easy and hard magnetization curves of Nd_2Co_(14)B compound have been measured withextracting-sample-magnetometer(μ_0H_(max)=6T)at 10~300 K.Magnetic anisotropy constants K_1 and K_2have been determined by fitting the hard magnetization curves,in which only K_1 ,K_2 and misalignment anglehave been taken as fitting parameters.The values of K_1 and K_2 at 4.2 K were derived by extrapolation.Anisotropy coefficients,x_2~° and x_4~°were derived from the anisotropy constants.The anisotropy constant K_2increases rapidly with increasing temperature when TT_(sr).The temperature depen-dence of the magnetic anisotropy coefficient x_2~° was fitted with the formula.The anisotropy coefficients x_2~°can be well described by the tenth-power law from 4.2 K to T_(sr)and by the sixth-power law from T_(sr_ to 300 K.  相似文献   
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