奥氏体不锈钢低温气体渗碳过程中温度对渗碳层的影响

利用扫描电镜、电子探针、显微硬度计、CS电化学工作站研究AISI316奥氏体不锈钢经低温气体渗碳处理后渗碳层显微组织及力学特性的变化。结果表明,在450,470,500 ℃温度条件下,在AISI316奥氏体不锈钢表面获得10~33 μm的硬化层,随温度的不同,渗层深度、硬度梯度、耐蚀性能呈现不同的变化规律。     

基于物理模型的烟雾模拟

在分析研究流体物理特性算法基础上,提出一种新的烟雾模拟实现方法。该方法基于物理模型的求解简化方程模拟烟雾的动态变化过程。模型中采用了非粘性欧拉方程,通常它比其他用粘性Navier-Stoke方程建模的更适合用来对气体进行建模并且减少计算量。实验验证该模型还可以正确处理烟雾与移动的物体之间的相互作用。     

Phase field computations for surface diffusion and void electromigration in {mathbb{R}^3}

We consider a finite element approximation of a phase field model for the evolution of voids by surface diffusion in an electrically conducting solid. The phase field equations are given by a degenerate Cahn–Hilliard equation with an external forcing induced by the electric field. We describe the iterative scheme used to solve the resulting nonlinear discrete equations and present some numerical experiments in three space dimensions. The first author was supported by the EPSRC grant EP/C548973/1.     

奢华与经典集结羊城——第三届广州国际奢侈品展综述

尽管世界经济的大气候正倍受席卷全球的金融海啸的剧烈挤压,集奢华与经典于一体的第三届广州国际奢侈品展仍然于2008岁末（12月6～8日）在地处羊城繁华商业中心的广州锦汉展览中心隆重上演。历时3天的展会围绕“体验奢华盛典、品味尊贵人生”这一高端定位,为广州、深圳乃至南中国财富时尚人士体验奢侈品所蕴藏的深刻内涵,为国内外奢侈品牌搭建了一个展示和互动的舞台。     

Mesostructured mixed Mo–V–Nb oxides for propane ammoxidation

Mesostructured Mo–V–Nb mixed oxide phases were prepared by reacting inorganic precursors in the presence of cationic, anionic and alkylamine surfactants. The occurrence of these mesostructured phases was explained in part by charge-matching considerations at the inorganic–organic interface. Other interactions, such as covalent bonding between the surfactant headgroup and metal atoms, could direct the self-assembly process. Despite of the limited thermal stability of the mesophases, the air-calcined phases were catalytically active and selective for propane ammoxidation to acrylonitrile and acetonitrile. The selectivities to acrylonitrile and acetonitrile were as high as 26 and 49 mol%, respectively, at 66% propane conversion.     

传统风格建筑钢框架结构拟静力试验研究

为研究传统风格建筑的钢框架结构的破坏形态和抗震性能,以位于抗震设防烈度8度区的一传统风格建筑钢框架结构为原型,按1∶2缩尺比例制作了试验模型,对其进行了低周反复加载试验。试验中观察了钢框架结构的受力过程及破坏形态,得到了结构的荷载-位移滞回曲线、骨架曲线、应变特征、延性、耗能性能、刚度与承载力退化等。试验结果表明: 传统风格建筑钢框架结构的斗、栱构件在水平荷载作用下可作为第一道抗震防线,梁端塑性铰发展充分,满足“强柱弱梁、强节点弱构件”的抗震要求;滞回曲线出现捏拢现象,呈Z形变化,表现出剪切滑移特征,与常规钢框架结构有明显的差异;在加载前期刚度退化较为显著;结构破坏时,极限位移角达到1/20,承载力退化系数接近0.9,表现出良好的抗倒塌能力和稳定的承载力。     

探究我国建筑管理教育模式的创新

随着经济全球化、经济体制改革的进一步发展,技术和知识成为了国家可持续发展的重要因素。我国在建筑管理以及整个建筑行业,依托天然资源的优势随着环境资源的匮乏已逐渐衰退,新经济时代需要知识和创新技术的支持。这其中建筑管理教育模式成为重中之重,我国在建筑管理教育模式上虽然在不断改革和完善,但是仍有诸多需要探讨的问题。本文针对现阶段建筑管理教育模式的现状,就创新方面给出几点浅薄的意见。     

Home-making practices and social protection across borders: an example of Turkish migrants living in Germany

This article explores how Turkish migrants in Germany turn their physical houses into homes through actual day-to-day practices. It does so by drawing on participant observation and qualitative interviews. Rather than referring to home merely as a physical place, this article investigates in detail migrants’ home-making practices, particularly those activities related to social protection. In making their homes, migrants simultaneously make reference to multiple locales, material artifacts, and social relationships in countries of emigration and immigration. Through the examination of home-making practices, this article is an attempt to portray the symbolic and material expressions with transnational elements of the home unfolding in migrants’ everyday life.