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1.
The residual intergranular strains in textured Zircaloy-2 plate samples induced by cooling from 823 K to ambient temperatures, by cold-rolling by 1.5% and 25% and by deforming in tension by 1.5% were measured by neutron diffraction. The strong rolling texture, which gives rise to two ideal orientations, permitted the interpretation of much of the data in terms of strain tensors for the two orientations. The experimental results were compared with calculations based on the elasto-plastic self-consistent model with no adjustable parameters. Close agreement was obtained for samples in the as-cooled state and deformation in tension by 1.5% but the agreement is less satisfactory for cold-rolling. 相似文献
2.
MCM-41 silicates prepared in the presence of octyltrimethylammonium bromide either by a conventional method or by post-synthesis
hydrothermal treatment were characterized by nitrogen adsorption in a wide range of relative pressure from 10-6 to 1. Hydrothermally restructured samples were found to have lower BET surface areas, lower external surface areas and thicker
silica walls than the non-treated sample. More importantly, in addition to their characteristic mesopores (ca. 3 nm), they
were shown to have considerable amounts of micropores. The relative amount of micropores and mesopores was shown to be dependent
on the treatment conditions. Thus, it is demonstrated that the postsynthesis hydrothermal restructuring is a convenient synthesis
route to MCM-41 silicates with bimodal pore size distribution involving controllable amounts of microporosity.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Jeong-Ha You 《Journal of Nuclear Materials》2005,336(1):97-109
Fibrous metal matrix composites possess advanced mechanical properties compared to conventional alloys. It is expected that the application of these composites to a divertor component will enhance the structural reliability. A possible design concept would be a system consisting of tungsten armour, copper composite interlayer and copper heat sink where the composite interlayer is locally inserted into the highly stressed domain near the bond interface. For assessment of the design feasibility of the composite divertor concept, a non-linear multi-scale finite element analysis was performed. To this end, a micro-mechanics algorithm was implemented into a finite element code. A reactor-relevant heat flux load was assumed. Focus was placed on the evolution of stress state, plastic deformation and ductile damage on both macro- and microscopic scales. The structural response of the component and the micro-scale stress evolution of the composite laminate were investigated. 相似文献
4.
Y. Dai H. Glasbrenner V. Boutellier R. Bruetsch X. Jia F. Groeschel 《Journal of Nuclear Materials》2004,335(2):232-238
Liquid-solid reaction under irradiation (LiSoR) experiments are aimed at understanding the effects of liquid lead-bismuth eutectic (LBE) corrosion and embrittlement under irradiation on structural materials, which is one of the key items of the materials R&D for the future accelerator-driven system (ADS). The LiSoR setup is basically a LBE loop with a test section irradiated with 72 MeV protons. The second irradiation was conducted for about 34 h and terminated after a leakage of LBE was detected. Post-irradiation examinations (PIE) are being performed on both the tube and tensile specimen in the test section. Optical microscopy, scanning electron microscopy, transmission electron microscopy and microhardness tests have been completed. The results show that a crack formed in the irradiation zone of the tube. In the material in the irradiation zones of both the tube and the tensile specimen dislocation cell structure is well developed, which indicates heavy deformation due to thermal fatigue. The crack should start at the inner surface and propagate to the outer surface. The fracture surfaces of the crack are dominated by a brittle cleavage fracture mode. However, on the surfaces of the tensile specimen, no microcracks are observed. 相似文献
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可修排队系统中可靠性指标的分解 总被引:2,自引:0,他引:2
本文提出了一种分析可修排队系统的新信息处理-分解法,应用该方法我们重新讨论了服务器可修的M/G/1排队系统,获得服务器在时刻t失效的概率和在(0,t]中失效的平均次数这两个主要可靠性指标的分解结果,而且进一步分析了服务器可修的GI/G1排队系统。值得注意的是本文提出的解解法新颖、简洁。 相似文献
8.
TD-SCDMA网络中3G-324M协议栈的研究与实现 总被引:1,自引:0,他引:1
本文简要介绍了3G-324M协议栈的主要内容。详细说明了3G-324M协议栈中H.223协议模块以及H.245协议模块的实现方法。描述了MONA(Media Oriented Negotiation Acceleration Procedure)协议的过程。 相似文献
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