Effects of Stitcing on the Buckling Strength of Stitched Composite Laminates

A theoretic model is proposed based on the mechanism of the buckling failure of the stitched composite laminates containing delaminations. The buckling strength of the stitched composite laminates under the in-plane compressive load is predicted. The critical percentage elongation of the stitching thread is taken into account as a control parameter of the buckling failure. The energy method is used to calculate the buckling strength of the stitched composite laminates, and the minimal potential energy is used to calculate that of the unstitched composite laminates. The result shows that the buckling strength of the stitched composite laminates is larger than that of the unstitched composite laminates. The effects of stitching technical parameters such as the stitch thread diameter, stitch step and stitch space on the stitched composite laminates are also analyzed.     

FEM on Coupled Hydromechanical Dynamic Response of Geogrid Reinforced Soil Retaining Wall

Geogrid reinforced soil retaining wall(GRSRW) is composed of panel,geogrid and soil,its coupled hydromechanical structural characteristics are increasingly emphasized in practice.In this paper,based on the characteristics of the reinforcement-soil interaction,the grogrid and soil around it with a definite thickness were regarded as a kind of composite material with strain-compatible condition.A saturated porous media model was introduced to simulate the soil and reinforcement-soil composite material hereby and the mathematic model for numerical analysis on structural characteristics of GRSRW was built up.The FEM equations were deduced from the standard Galerkin procedure,resolving these equations,we can gain the relevant dynamic response of saturated GRSRW.     

Composition of Application Based on Business Rule

In order to support flexibility and reusability of application composition based on Internet,with business rule and Aspect-Oriented Programming(AOP) which divides a business process into a control business process and a core business process,the authorsgive composition mechanism.A technique of implementation is analyzed.At last,the primary application of the above work in Chongqing of China is introduced,as well as some effects acquired.     

三维复合材料复合裂纹特殊边界元法

利用两相复合材料位移基本解，将受复合载荷作用下复合材料三维裂纹问题，归为求解一组超奇异积分方程，并分析了对裂纹尖端应力奇性和方程组求解理论方法；进而以反映裂纹前沿应力奇性的密度函数基本解表示位移间断，根据Taylor积分及其特征展开特性，给出方程组数值求解方法；最后，以三维矩形裂纹为例，讨论了应力强度因子（SIFs）收敛性及其变化规律。     

回流比对UASB反应器处理难降解化工综合废水运行性能的影响

本试验研究了污水回流比（R）对UASB反应器处理难生物降解的化工综合废水（BOD5／CODcr～O.3）运行性能的影响。结果表明：回流比对CODcr去除率影响明显，当R=2时（水力负荷率HLR为0.426m^3·m^-3d^-1，液体升流速UFV为0.0983m·h^-1），CODcr，最大去除率为60％，基质降解速率SDR为1.122kgCOD·m^-3d^-1。当R=3时（HLR 0.432m^3·m^-3d^-1，UFV 0.131m·h^-），CODcr最大去除率为62.2％，SDR为1.163kgCOD·m^-3d^1。回流作用强化了污染物与微生物细胞之间传质效果，可能是反应器运行性能提高的重要原因。另外，回流引起UASB反应器内部水力学特性发生改变，使基质浓度梯度减小且混合均匀，VFA的产生量减少，VFA积累引起的抑制作用被消除。     

隔膜计量泵的改良设计与汽蚀性能的提高

针对应用于石油化工装置上的进口隔膜计量泵容易产生的汽蚀问题，对隔膜泵复合隔膜、柱塞密封副、液压平衡与补偿阀结构进行了改良设计，采用较大承载能力的机座、独特阶梯式活塞、加大直径的活塞、PTFE＋NBR复合隔膜，改良放气安全阀及油浸没式补偿系统等方法，提高了隔膜计量泵的汽蚀性能；通过对改造的隔膜计量泵与原有的计量泵进行的汽蚀试验对比，给出了隔膜计量泵性能与现场使用的最佳匹配工况。改良的结构设计和新型材料的选用大大提高了计量泵的汽蚀性能。     

复合材料模型分析加筋地基承载力

利用复合材料模型模拟加筋地基，按照土塑性力学分析加筋地基的变形和破坏，并按传统滑移线解法推导出浅基础加筋地基的承载力设计公式，利用实例比较探讨了本文方法与传统极限分析法的优缺点。     

BMC材料气门罩壳的振动分析

在内燃机表面噪声中,气门罩壳是主要的噪声源之一.将BMC材料用于气门罩壳,采用有限元方法对其进行模态分析和谐响应分析,并与铸铝罩壳进行了比较,计算结果表明,BMC材料用于气门罩壳具有减振、降噪的作用.     

混农间作对兴安落叶松人工林土壤生态条件的影响

以落叶松人工纯林及落叶松与大豆混农间作人工林下土壤为研究对象,对不同林分下土壤物理性质和化学性质进行测定及比较分析,结果表明:混农林的土壤容重低于纯林,土壤总孔隙度和含水量大于纯林。另外,落叶松与大豆间作使土壤有机质含量增加,全N、速效N、P、K的含量增加,其中间作林土壤中N素含量增加尤为明显。     

资源节约型高性能竹木复合板的研制

采用多种无屑切削方式,将竹材、木材及制材、旋切剩余物——边皮、木芯,加工成不同形态的构成单元,组合成合理的复合板坯结构,热压胶合成一种竹木复合板材。检测结果表明：半成品加权平均利用率可达90．1％,成品板材的出材率为63．1％,居各类型胶合板之首;板材纵横强度之和：静曲强度为113．1MPa,弹性模量为9578MPa,是一种资源节约型高性能的竹木复合板材。