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71.
Thick films of superconducting oxides, YBa2Cu3O7-, were successfully made by conventional screen-printing technology on Al2O3, MgO, and ZrO2 substrates. Interdiffusion between the superconductive film and substrate was investigated using analytical electron microscopy. The results indicate that MgO and ZrO2 are superior to Al2O3 for substrate materials.  相似文献   
72.
Wang  Kun  Tian  Qiang  Hu  Haiyan 《Multibody System Dynamics》2021,51(1):1-19
Multibody System Dynamics - Computational prediction of 3D crutch-assisted walking patterns is a challenging problem that could be applied to study different biomechanical aspects of crutch walking...  相似文献   
73.
Rakhsha  M.  Yang  L.  Hu  W.  Negrut  D. 《Multibody System Dynamics》2021,53(1):29-57
Multibody System Dynamics - A multibody dynamics-based solution to the fluid dynamics problem is compared herein to two established Lagrangian-based techniques used by the computational fluid...  相似文献   
74.
Wu  Zheng-tian  Hu  Fu-yuan  Zhang  Yang  Gao  Qing  Chen  Zhen-ping 《中南大学学报(英文版)》2017,24(11):2717-2724
Journal of Central South University - Possessing the unique and highly valuable properties, graphene sheets (GSs) have attracted increasing attention including that from the building engineer due...  相似文献   
75.
Crystalline metal-organic framework cobalt(Ⅱ) benzenetricarboxylate Co3(BTC)2?12H2O(MOF-Co) has been prepared using solvothermal method. The reaction of cobalt(Ⅱ) nitrate and 1,3,5-benzenetricarboxylic(BTC) acid in a mixed solution of N,N-dimethylformamide(DMF)/C2H5OH/H2O(1:1:1, ν/ν) at low temperature for short reaction times produced this crystalline compound. Compared with traditional hydrothermal method, a mixed solution method for the synthesis of crystalline metal complex was found to be highly efficient. After water molecules were removed from this metal complex, its exposed nodes served as active sites. When this MOF-Co was employed in the oxidation of CO, it showed good catalytic properties causing 100% conversion of CO to CO2 at low temperature of 160 ℃.  相似文献   
76.
Based on some assumptions, the dynamic analysis model of anchorage system is established. The dynamic governing equation is expressed as finite difference format and programmed by using MATLAB language. Compared with theoretical method, the finite difference method has been verified to be feasible by a case study. It is found that under seismic loading, the dynamic response of anchorage system is synchronously fluctuated with the seismic vibration. The change of displacement amplitude of material points is slight, and comparatively speaking, the displacement amplitude of the outside point is a little larger than that of the inside point, which shows amplification effect of surface. While the axial force amplitude transforms considerably from the inside to the outside. It increases first and reaches the peak value in the intersection between the anchoring section and free section, then decreases slowly in the free section. When considering damping effect of anchorage system, the finite difference method can reflect the time attenuation characteristic better, and the calculating result would be safer and more reasonable than the dynamic steady-state theoretical method. What is more, the finite difference method can be applied to the dynamic response analysis of harmonic and seismic random vibration for all kinds of anchor, and hence has a broad application prospect.  相似文献   
77.
Hu  Chuang  Zang  Guo-Long  Luo  Jun-Tao  Liu  Qi  Zhao  Quan 《Journal of Applied Electrochemistry》2021,51(6):847-859
Journal of Applied Electrochemistry - The electrocatalytic reduction of CO2 is a promising research direction in resource utilization and sustainable energy development. However, there is still a...  相似文献   
78.
对20G高压锅炉管产生裂纹的原因进行了分析,结果表明是冷拔工艺不当所致。  相似文献   
79.
为使硫量波动的高炉铁液能适应大型离心铸造球铁铸管生产,研制了一种成本较低廉、添加操作简单的复合功能型脱硫剂。其主要组分包括强脱[S]去[O]材料钝化镁粒、碳化钙,增加石墨核心元素Zn和膨胀集渣材料珍珠岩,以及能抑制反球化作用和净化铁液的材料等。采用冲入法进行球化处理,这种脱硫剂覆盖在球化剂和孕育剂上,使用方法简单,效果良好。  相似文献   
80.
Stress distribution in the gradient multi-layered surface under a sliding contact was investigated using finite element method(FEM). The main structure parameters of layered surface discussed are total layer thickness,layer number and elastic modulus ratio of layer to the substrate. A model of multi-layered surface contact with rough slider was studied. The effect of the surface structure parameters on the elastic-plastic deformation was analyzed.  相似文献   
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