双材料平面斜裂纹问题超奇异积分方程方法

由双材料平面问题的弹性力学基本解，应用互等功定律和坐标变换，得到双材料平面任意斜裂纹问题位移场及应力分量表达式，经代入裂纹岸应力边界条件，获得以裂纹岸位移间断作为基本未知量的超奇异积分方程组；通过适当的积分变换，用有限部积分原理处理超奇异积分，建立该问题的相应数值算法。文中对任意位置的裂纹问题进行计算，并较为系统地分析界面对裂纹应力强度因子的影响，当裂纹垂直或平行于双材料界面时，计算结果与已有结果一致。     

基于有限元分析的冰箱端盖数值分析与结构优化

有限元法在结构设计中应用将越来越广泛,在冰箱设计中设计者可以充分利用有限元工具,在满足设计要求下开发设计出结构优化、成本更加低廉的产品.本文针对冰箱门端盖开裂的问题,运用有限元分析工具进行分析与优化,并通过应力应变测试系统进行矫正,最终通过对门端盖结构优化解决了门端盖开裂的问题.     

Pilot scale treatment of low turbidity water using compound bioflocculant and polymerized aluminium ferrum chloride

To investigate the application of compound bioflocculant (CBF) in drinking water treatment at pilot plant,CBF and polymerized aluminium ferrum chloride (PAFC) coagulant were used to treat raw water taken from Longhupao Reservoir in Heilongjiang Province for the removal of turbidity,COD,UV254 and residual Al. Coagulation test shows that the coagulation enhanced by CBF and PAFC exhibits more effective performance than that enhanced by the individual of them,and the total combination dosage is lower than that of the individual. The residual Al from PAFC can be removed efficiently by CBF. The removal efficiency of turbidity reaches 76.6% by combining CBF of 2 mg/L and PAFC of 15 mg/L,COD is decreased from 3.80 mg/L to 1.62 mg/L,and the concentration of residual Al is only 0.033 mg/L in the product water. It can be speculated that adsorption-bridging and sweep-coagulation processes are predominant in the flocculation process by the combination of CBF and PAFC.