Dynamic responses and damages of water-filled pre-pressurized metal tube impacted by mass

An account is given of some principal observations made from a series of experiments in which three-span pipe beams were subjected to central impact by indenters with different nose shapes. These pipes were filled and pre-pressurized with water in order to identify the main effects produced by the fluid–structure interaction. In comparison, the impact experiments of the pipes with no water were also carried out. The perforation failure modes and corresponding critical impact energies were obtained in different test conditions. The experimental results indicated that the critical perforation energy and the deformation of the wall of the pipe were significantly influenced by the presence of the water and the pressure.     

Effect of polymerization conditions on o‐phenylenediamine and o‐phenetidine oxidative copolymers

A series of new o‐phenylenediamine (OPD)/o‐phenetidine (PHT) copolymers with partly phenazine‐like structures has been successfully synthesized at three polymerization temperatures by chemically oxidative polymerization in four different polymerization media. The molecular structures and properties of the resulting OPD/PHT polymers were investigated by IR, UV–vis and high‐resolution ¹H NMR spectroscopies, and DSC, in order to ascertain the effect of reaction temperature, comonomer ratio and acid medium. The copolymerization mechanism of OPD with PHT monomers has been proposed. It is found that the statistical OPD/PHT copolymer obtained at a temperature of 118 °C has a higher degree of polymerization than that obtained at 12–17 °C. The OPD content in the copolymers calculated from NMR spectroscopic analysis is higher than that in the feed OPD content, whereas the OPD content calculated from element analysis is slightly lower than the feed OPD content. It can be predicted that denitrogenation takes place in the OPD units during the polymerization process at OPD/PHT molar ratios of 90/10 and 100/0. These OPD/PHT copolymers exhibit a much better solubility than the OPD homopolymer, hence suggesting an incorporation of PHT units into the phenazine structure of the homopolymer. The thermal behavior of the copolymers was also studied. Copyright © 2004 Society of Chemical Industry     

EXPERIMENTAL RESEARCH ON EFFECT OF MAIN-FLOW SWING ON FLOW TURBULENCE STRUCTURE

It is mentioned in this paper that the adjustment of flow structure occurs when themain-flow swings.The changes of turbulence structure and flow energy loss in the indoor rivermodel are measured.The experimental data are presented for the first time for the further studyof complicated river flow structure.     

A possible structure of the casein micelle based on high-resolution field-emission scanning electron microscopy

New electron micrographs, produced using the technique of Field Emission Scanning Electron Microscopy, showing the details of the micellar surface, are presented. The images show the micellar surfaces without any coating, and suggest that the surface of the micelle may have a much more complex structure than has previously been demonstrated. Although there appear to be no spherical subunits (submicelles), there is evidence for the organization of the caseins into tubular structures within the micelle. The surface is not smooth, and contains gaps between the substructures. The observations are discussed in terms of published models of micellar structure, where is it suggested how the depiction of the micellar surface can be used to explain certain factors of its reactivity and behaviour.     

太阳电池板结构应力-应变状态分析

多层胶接是太阳电池板的结构特点,由于不同材料的弹性模量、热膨胀系数和泊松比不同,在温度场 作用下会产生热应力应变,在多次热交变过程中热应力．应变累积最后导致结构层间剥离,因此研究温度场作用 下太阳电池板结构应力应变状态具有非常重要的实际意义。本文推导了模拟太阳电池板结构应力-应变状态的一 维模型,该模型同样适用于分析多层胶接结构应力应变状态。     

Fixed point theorems on fuzzy normed linear spaces

In this paper, definitions of strongly fuzzy convergent sequence, l-fuzzy weakly convergent sequence and l-fuzzy weakly compact set are given in a fuzzy normed linear space. The concepts of fuzzy normal structure, fuzzy non-expansive mapping, uniformly convex fuzzy normed linear space are introduced and fixed point theorems for fuzzy non-expansive mappings are proved.     

昆2井优快钻井及油气层保护技术

昆2井是一口位于柴北缘西段的昆特依凹陷潜伏Ⅰ号圈闭上的风险探井,设计井深为5950m。针对柴北缘深探井存在的主要技术难题,制定了昆2井的技术对策。通过对钻井设备的优选、井身结构的优化、钻头及钻具组合的优选、钻井参数及钻井液性能的优化、油气层保护技术的研究与应用,形成了一套适合于柴北缘的优快钻井技术,使昆2井的完钻井深达到5950m。与邻区的深探井平均水平相比,在井深增加888m、大尺寸井眼段更长的前提下,昆2井的钻井、完井周期分别缩短了98.75d、124.2d,钻机月速度增加了317m/台,平均机械钻速增加了0.82m/h。根据“理想充填新理论”,确定了保护油气层的最优复配暂堵方案,利用该方案所配制的钻井液其渗透率恢复值达到了87.5%以上,流变性能良好,滤失量低,对改善泥饼质量、增强井壁稳定性有明显的效果。     

元刊杂剧特指式反问句

详细描写了元刊杂剧特指式反问句的结构及意义，指出反问句用疑问句的形式表达与语表形式相反的“言外之意”，其基本语用意义是评价，特指式的反问意义是在具体的语言环境中形成的。     

基础锚栓预埋加固方案

结合工程实例 ,介绍轻钢结构系统基础锚栓预埋、加固解决方案 ,并介绍了加固系统的制作及使用方法 ,可供工程人员参考     

埕岛油田东部斜坡带东下段沉积特征及油藏类型研究

埕岛油田东部斜坡带下第三系油藏以三角洲、浊积扇砂体隐蔽油气藏为主，储层埋藏深、厚度变化大，油气成藏复杂。通过对该带的沉积特征、沉积体系和沉积物源的研究，指出其东下段砂体的分布主要受物源和沉积相带两方面控制，砂体只有在有效圈闭情况下才能成藏，并且从构造上总结了三种油藏类型。最后指出该带下一步勘探重点是沿主物源方向展布的、成藏条件良好的各种砂体。