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本文简要介绍了国外在开发超酸性气体过程中遇到的材料选择、腐蚀监测、水化物堵塞、超酸性气的处理和加工等问题所采取的措施和办法。     

Finite element analysis of partly wrinkled reinforced prestressed membranes

Wrinkling is a well known phenomenon experimented by tension membranes in Civil Engineering applications. This paper will present an efficient numerical technique for the computational simulation of such wrinkles in a prestressed membrane. In particular, the relaxed energy approach (Pipkin in IMA J Appl Math 36:85–99, 1986) is particularized for prestressed membranes (Gil in Textile composites and inflatable structures, CIMNE, 2003) undergoing moderate strains. Wrinkling conditions in terms of the Euler-Lagrange finite deformation tensor along principal directions will be obtained. This will provide a framework to describe properly the initial instant when wrinkles start to be encountered in a prestressed Saint Venant–Kirchhoff hyperelastic membrane. Subsequently, a modified Helmholtz’s free energy functional will be introduced with the purpose of describing the modified constitutive behaviour of the continuum after the onset of wrinkling. Consistent derivations of the stress tensor as well as the constitutive tensor will de depicted. The results will be particularized for membranes and cables in a Finite Element discretization basis. Some numerical examples will prove the accuracy and robustness of the described algorithm.     

双辊铸轧机生产工艺对组织和性能的影响

就用双辊铸轧机(TRC)生产薄、宽铸轧带技术进行研究并优化铸轧工艺。研究结果表明：3mm厚的铸轧带不仅表面变形．而且整个厚度内部层都发生变形，表面层的铝基中具有较高的合金元素饱和度。     

Cohesive stresses and size effect in quasi-brittle materials

A novel approach to the derivation of Bažant’s size effect law is presented. Contrarily to the original Lagrangian derivation which hinged on energetic consideration, a Newtonian approach based on local stress intensity factors is presented. Through this approach, it is shown that Bažant’s size effect law is the first (and dominant) term in a series expansion for the nominal stress. Furthermore, analytical expressions forB are derived for selected specimen geometries.     

材质对蜂窝纸板缓冲性能的影响

对两种不同材质的蜂窝纸板静态应力应变性能和动态缓冲结果进行了比较分析。讨论了蜂窝纸板力学性能对应变速度的敏感性及两种纸板的缓冲性能差异。缓冲试验结果表明。在不同的冲击应变率下蜂窝纸板的材质影响蜂窝纸板缓冲性能。     

如何正确选择合适的耐蚀材料

文章较全面的介绍了如何根据设备、装置、构件所处的工作环境及使用条件进行防腐蚀设计,及其防腐蚀设计的内容和注意事项,选择合适的防腐蚀材料,确保产品的使用寿命     

Development of sealing compositions with nanostructure iron-based fillers

The possibility of utilizing nanopowders of iron and Fe-Co-Ni produced bu a thermochemical method in the fabrication of sealing composition materials is investigated. It is established that such hermetic sealing composition materials function reliably under extremal conditions and guarantee elevated strength of adhesion to the surface of the metal and high corrosion and temperature stability. __________ Translated from Poroshkaya Metallurgiya, Nos. 3–4(448), pp. 112–117, March–April, 2006.     

40Cr钢复合热处理强韧化

用光学及电子显微镜(SEM.TEM)观察不同热处理的40Cr 钢的冲击及断裂韧性断口、及金相组织,阐明其间相互关系;断口结构可反映断裂特征,组织情况;细化晶粒提高强度、塑性和冲击韧性,但却减少脆断的特性距离 l 因而降低 K_(1c)模;减少碳(杂质)偏聚而使其呈较均匀地分布,从而减少可诱发塑坑的较粗大的碳(杂质)化合物的析出,即增加塑坑的间距 di 以及增加塑断组成物。从而都可增加断裂临界应变 ef,都可以提高 K_(1c)40Cr 复合热处理既靠先超高温淬、回火以减少碳(杂质)偏聚,改善其分布,以反增加位错马氏体从而提高 K_(1c),也靠后淬、回火细化晶粒而提高强度、塑性和冲击韧性,各自发挥长处达到强韧化。     

锗酸铋（Bi4Ge3O12）单晶热物理性质的研究

本文用不同的测试技术和方法测定了锗酸铋(BGO)单晶的比热(300～800K)热膨胀系数(100～1100K)和导温系数(140～700K),进而导出了 BGO 单晶不同温度下的导热系数、定容比热、德拜温度和格虑内森数。本文还对 BGO 单晶热物理性质的变化规律作了理论解释。     

Hydrolytic stability and protective properties of polyurethane oligomers based on polyester/ether/polyols

The present study deals with effect of the type and chemical character of incorporated polyester/polyether blocks on the hydrolytic stability of crosslinked polyurethane oligomers. Diffusion parameters of the investigated polyurethane oligomers, giving information concerning chemical changes taking place in neutral, basic and acidic aqueous environments, have also been determined.