Numerical Simulations of the Transparency of Waterfront Bodies

Measured field data was used to analyze the factors which influence the transparency of the Nei River and to develop a multi-factor correlation for the transparency. A 2-D unsteady model which coupled analyses of the water flow, water quality, suspended sediments, and Chl-a was developed to simulate the changes in the transparency for various conditions. The model was then used to forecast the transparency of the Nei River. The suspended sediment concentration （SSC） was found to be the most important factor influencing the transparency, with high concentrations of CODMn and Chl-a also reducing the transparency to some extent. The transparency model is stable and precise, with relative errors between measured and calculated values of less than 15%. With the environmental scheduling schemes, the Nei River transparency can be significantly improved with a mean transparency in high-water years of 69.3 cm, normal-water years of 70.8 cm, and low-water years of 69.8 cm.     

5·12汶川地震中电力设施震害情况及其成因分析

根据5·12汶川地区地震灾害的现场考察和资料调研,首先介绍了汶川地震中四川电网的受灾状况,并对电网的地震受灾特点进行了归纳总结;然后,就四川电网的震害原因进行了分析．汶川地震中电力设施震害的主要原因是地震烈度远超出抗震设计烈度,同时,电力设施的特点及其缺陷也是震害严重的原因之一．最后,建议对现有电力设施进行抗震性能普查,新建电力设施需进行抗震设计,进一步提高我国电网的安全可靠性．     

动态回复和再结晶获得超细晶粒低碳低合金钢

利用电子背散射衍射(EBSD)技术研究了低合金钢在Ac1点以下大变形量应变(ε=1.5)过程中铁素体晶粒的细化机理,经过扫描电镜观察以及EBSD测定,其平均晶粒尺寸已细化到2μm以下,晶界主要以大角晶界为主,表明所形成的铁素体晶粒为稳定态的组织.在接近奥氏体区的温度,铁素体晶粒在强烈塑性应变条件下,其细化主要通过铁素体动态回复和再结晶完成,热加工参数Z=4×1016s-1,在Z>1×1016s-1条件下,铁素体通过动态再结晶进行细化是可以实现的.     

5·12汶川地震中电力设施震害情况及其成因分析

根据5·12汶川地区地震灾害的现场考察和资料调研,首先介绍了汶川地震中四川电网的受灾状况,并对电网的地震受灾特点进行了归纳总结;然后,就四川电网的震害原因进行了分析.汶川地震中电力设施震害的主要原因是地震烈度远超出抗震设计烈度,同时,电力设施的特点及其缺陷也是震害严重的原因之一.最后,建议对现有电力设施进行抗震性能普查,新建电力设施需进行抗震设计,进一步提高我国电网的安全可靠性.