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101.
The effect of dissolved oxygen(DO) on the stress corrosion cracking(SCC) of 310 S in supercritical water was investigated using slow-strain-rate tensile tests.The tensile properties, fracture morphology, and distribution of the chemical composition of the oxide were analyzed to evaluate the SCC susceptibility of 310 S. The results showed that the rupture elongation decreased significantly as the degree of DO increased. A brittle fracture mode was observed on the fracture surface, and only intergranular cracking was observed on the surface of the gauge section, regardless of the DO. Cracks were widely distributed on the gauge surface near the fracture surface.Oxides were observed in the cracks with two-layered structures, i.e., a Cr-rich inner oxide layer and an Fe-rich outer oxide layer.  相似文献   
102.
SF_6断路器灭弧室内三维电场数值模拟   总被引:3,自引:2,他引:1  
运用有限元法FEM对罐式SF6断路器断口附近三维电场进行了数值计算 ,以计算机辅助绘图为支撑 ,完成了SF6断路器三维电场的数值模拟。在三维电场数学模型的建立中考虑了屏蔽罩和并联电容器组的存在 ;对断路器不同三维剖面的等电位线分布及电场分布情况进行了分析 ;并将计算结果进行三维图形可视化处理及显示。  相似文献   
103.
铸件缩孔与缩松的图像模拟   总被引:1,自引:0,他引:1  
为了直观地显示铸件缩机与缩松的数值计算结果,设计了1种称之为仿X-Ray探测效果的显示技术。采用该技术来显示铸件的缩孔、缩松,可以达到类似X-Ray无损探伤的效果,提供给用户1幅透明的铸件模型图象使缩孔、缩松的位置一目了然。该技术已成功地应用于BUAA-CAST铸造过程仿真系统中。  相似文献   
104.
CLINICAL OBSERVATIONS: Three patients with previous pulmonary infections were recently admitted with rapidly progressive renal failure. Renal biopsy showed crescentic glomerulonephritis with deposits of IgA, C3c and C3d. Serology disclosed P-ANCA with high-titer anti-myeloperoxidase antibodies. Two out of three patients became dialysis dependent despite immunosuppression with methylprednisolone and cyclophosphamide. Renal function improved in both patients after 2 weeks and 9 months, respectively, permitting termination of hemodialysis. All patients benefited from immunosuppressive treatment which is currently still being continued. CONCLUSION: The data suggest that early immunosuppression is beneficial in patients presenting with crescentic rapidly progressive IgA GN and anti-myeloperoxidase antibodies, which may represent a novel subset of crescentic IgA GN associated with high-titer anti-myeloperoxidase antibodies constituting an overlap group between microscopic polyangiitis and IgA GN.  相似文献   
105.
程伟  崔航  曾二贤 《土工基础》2011,25(2):38-43,50
为了研究路面结构的振动特性,基于2.5D有限单元方法建立了高速公路路面结构和下卧层地基在交通荷载作用下的三维耦合振动模型。通过计算分析了路面振动加速度的变化规律和路面结构的面层、基层和底基层中的应力分布,考虑了车辆运行速度、荷载振动频率、路面分层结构形式、路面材料和下卧层地基模量等因素的影响。结果表明:车辆运行速度和荷载振动频率对路面结构的振动响应有着显著影响;同时随着路面材料刚度的提高,路面结构振动会降低,在实际工程中可通过选用合适刚度的路面材料以获得路面性能的较大改善。  相似文献   
106.
Apolipoprotein B (ApoB) plays a crucial role in lipid and lipoprotein metabolism. The effects of APOB locus variants on lipid profiles, metabolic syndrome, and the risk of diabetes mellitus (DM) in Asian populations are unclear. We included 1478 Taiwan Biobank participants with whole-genome sequence (WGS) data and 115,088 TWB participants with Axiom genome-wide CHB array data and subjected them to genotype–phenotype analyses using APOB locus variants. Five APOB nonsynonymous mutations, including Asian-specific rs144467873 and rs13306194 variants, were selected from participants with the WGS data. Using a combination of regional association studies, a linkage disequilibrium map, and multivariate analysis, we revealed that the APOB locus variants rs144467873, rs13306194, and rs1367117 were independently associated with total, low-density lipoprotein (LDL), and non-high-density lipoprotein (non-HDL) cholesterol levels; rs1318006 was associated with HDL cholesterol levels; rs13306194 and rs35131127 were associated with serum triglyceride levels; rs144467873, rs13306194, rs56213756, and rs679899 were associated with remnant cholesterol levels; and rs144467873 and rs4665709 were associated with metabolic syndrome. Mendelian randomization (MR) analyses conducted using weighted genetic risk scores from three or two LDL-cholesterol-level-associated APOB variants revealed significant association with prevalent DM (p = 0.0029 and 8.2 × 10−5, respectively), which became insignificant after adjustment for LDL-C levels. In conclusion, these results indicate that common and rare APOB variants are independently associated with various lipid levels and metabolic syndrome in Taiwanese individuals. MR analyses supported APOB variants associated with the risk of DM through their associations with LDL cholesterol levels.  相似文献   
107.
Based on the conservation of energy, a coupling heat‐transfer physical model and a set of mathematical equations are put forward to calculate the main components of the thruster, including the capillary injection tube, the aggregate organ, the injection plate, and the bracket when they are exposed to a space cryogenic environment. The typical temperature drop course of a 10N monopropellant thruster has been calculated by this computational model. The calculation results agree well with test data in a vacuum cryogenic simulation experiment performed on the ground. The temperature of the injection tube provides the thermal boundary conditions for the propellant temperature drop calculation while flowing through it. This provided the criterion to judge whether the propellant freezes or not. The upper stage has no air conditioning, so the injection tube is a weak link for the cryogenic reliability work of the thruster. This is considered one of the most important areas of the whole for reliability research. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(2): 85–95, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20144  相似文献   
108.
This paper examines a previous empirical study on the complexity of structured programming techniques and finds that all five structured solutions contain programming errors, although they are all based on Nassi-Schneiderman diagrams. The programming errors, of course, invalidate the previous empirical results on the complexity of structured programming techniques. An elegant programming solution to the multi-level control break reporting logic problem is then presented.  相似文献   
109.
视频通信中的错误掩盖方法研究   总被引:2,自引:0,他引:2  
误码几乎是不可避免出现在数字视频通信中,其在空间和时间上的扩散对重建图像质量有着不良影响,错误掩盖技术即是用来解决这个问题的重要途径之一。文章论述了国内外错误掩盖技术的现状及其典型算法,分析了它们的应用范围和性能,并指出了其发展前景。  相似文献   
110.
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