用MFRG和DPIR方法解三峰场中自旋为2的TIM模型

本文用平均场重整化群方法(MFRG)和离散路径积分表示(DPIR)的方法来研究自旋为2的无规横向伊辛模型在三峰分布纵场中(RFTIM)的相图和临界性质。     

Advances in Tube Hydroforming - An Enabling Technology for Low-Mass Vehicle Manufacturing-Material, Lubrication, Loading, Simulation Issues, and Alternatives

The tube hydroforming process (THF) has recently found a wide application opportunity in the automotive industry, and is of increasing interest to other industries as well. The increased interest stems from the fact that, through the THF process, manufacturers are able to produce complex, consolidated,lightweight parts with reduced number of post-processing than through alternative metal forming techniques.In order to fully realize the benefits of this technology, various aspects have been under investigation in academia and industry world-wide. In this paper, effect of loading path, incoming material variation, and lubrication on the robustness of the hydroforming process and final part specifications are summarized based on previous experimental and computational work. In addition, the simulation of hydroforming and examples are presented in comparison with experimental findings. Briefly, results emphasized the importance of the loading path design whereas material variation within the experimentally tested range was not found to be significantly effective on the final part specifications. Selection of a lubricant for hydroforming of a frame rail part was presented demonstrating several aspects of lubrication selection methodology. Results of friction experiments show that only thickness, axial feeding, and force measurements are good indications of lubricant performance as these are found to be strongly discriminative.     

揭开血红蛋白之奥秘

揭开血红蛋白之奥秘孙家明译杜克大学的研究人员对似是而非的问题非常感兴趣，他们最近又回到了探索生命最深奥的秘密上来：红血球是怎样将氧送到组织内的又是怎样将二氧比碳带出来的这个问题。现在，科学家们在今年３月２１日的帕然》杂志上报道．他们已解开了这一对矛盾...     

不同原料气体直流电弧等离子体制备金刚石薄膜的比较研究

迄今,在金刚石的热力学亚稳相气相合成金刚石薄膜已有许多成熟的方法,如热丝法、微波等离子体法、射频等离子体法、直流电弧等离子体法、空心阴极法、以及氧炔焰法等。作为原料气体的碳氢化合物一般选用甲烷,金刚石薄膜的生长机理和工艺研究多集中在     

钴酸锶镧阴极的性能及其在封离式CO2激光器中的应用

对钴酸锶镧结构、导电性及催化活性等进行了研究，结果表明，它是制作阴极的良好材料，用它制作封离式ＣＯ２激光器的阴极，可提高激光器的性能。     

内贮固体催化剂式TEACO2激光器的质谱诊断

利用自行建立的四极质谱诊断系统对内贮固体催化剂式陶瓷外壳ＴＥＡＣＯ２激光器进行了寿命过程中的质谱分析，讨论了激光输出能量与气体成分变化的对应关系，发现激光输出能量与激光器内的水蒸汽浓度密切相关。     

天然气水合物的研究现状和前景

天然气水合物是继煤、石油和天然气等能源之后的一种潜在的新型能源，是在高压、低温条件下形成的冰状固体物质，它广泛存在于极地地区，通常与永冻土带的近海和深海以及陆架和岛屿边缘密切相关。本文介绍天然气水合物的概念，物化性质等，综述了国内外天然气水合物的研究现状并指出其发展趋势，最后得出，天然气水合物的研究意义重大。