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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.
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.
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   
5.
本文介绍在没有专用量具、量仪的条件下,在双面啮合综合检查仪上用比较测量法,测出三槽丝锥的1/2M值,然后计算出中径d2的方法.  相似文献   
6.
基于ATMEGA64L微控制器和TRH031M读卡芯片设计了工作频率为13.56MHZ的RFID读写器系统,把RFID技术应用到物流系统中.  相似文献   
7.
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  
唐应辉 《电子学报》1996,24(11):18-21
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   
9.
LTE 230MHz电力无线专网是解决电网末端"最后一公里"的主要解决方案。目前230MHz电力无线通信系统有LTE-G 230MHz和IoT-G 230MHz两种技术体制,两种技术的帧结构存在明显差异,文章拟对两种技术体制的频谱效率进行分析。  相似文献   
10.
物联网本质是 ICT 与国民生产中更多行业的联姻。标准是促进物联网应用形成规模经济效应和避免碎片化的重要手段,在涉及重大基础设施建设的项目中标准更是客户采购的前提条件。通信行业达成共识成立全球性的物联网标准组织迈出了重要的一步,以业务层和终端管理的标准化作为起点是合理的步骤,也符合整个 ICT 行业的利益。  相似文献   
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