Mathematical Medel for Heat Transfer on Solididing Ladle of Hot Metal

In this paper,solidifinG ladle of hot metal has been studied from the point ofview of heat transfer.A mathematical model,which is applied to predict the shape and the thicknessof solidifing layer,has been developed. The theoretical calculated results agree with the appliedresults in preduction. The effects of various paramenters,such as the circulating times, the inner-surface temporature of ladle and the different refractories,on the shape and the thickness ofsolidifing layer have been discussed.These are contributed to reduce the solidifing ladle of hot metal.     

Application of Water Quality Standand Leuel Method in Eualuazing Status Quo of Heauy-Metals Pollution in Riuers

The status quo of heauy-metals pollution in water phase of course of Long-Tan hydropower statian was eualuated by water Quality Standand Level Method. With this special method,mone objectiue and definite results were obtained.     

METAL MATRIX PARTICULATE COMPOSITES BY SPRAYING CODEPOSITION

The spraying codeposition process is used to produce metal matrix paniculate composites, whose technical procedure and main processing parameters are analyzed. The microstructure of the composites is examined and the properties are tested. The solidification characteristics in the spraying deposition and solidification process are discussed. The results indicate that several problems involved in conventional methods can be overcome with this technique to preduce metal matrix paniculate composites. The reinforce particles are dispersed in the matrix homogeneously without solidification segregation. Compared with the matrix alloy,the composite proves to be harder and has excellent wear resistance.     

污水灌溉条件下作物对土壤重金属吸收特征比较

通过采样和化学测试，对污水灌溉条件下，小麦、水稻、蚕豆和油菜果实中Cu、Zn、Pb、Cr和Cd的含量及土壤中重金属本底浓度进行测定和分析。结果表明，污水灌溉对4种作物吸收土壤重金属的能力影响不显著，而不同作物种类对这种吸收能力的影响表现出显著的差异。     

板料参数对抗皱性的综合影响研究

应用多元统计分析方法进行板料参数对抗皱性的综合影响研究，得到的全回归方程能客观地反映各种参数对抗皱性的影响程度和影响方式。为分析板料在成型过程中产生的缺陷和生产具有高抗皱性的板材提供依据。     

活塞中凸型线数控加工的一种逼近方法

针对发动机活塞纵剖面型线的不规则性,提出了采用3次样条插值和双圆弧拟合相结合逼近加工曲线的方法,推导出了适用于计算机编程的3次样条插值计算公式;分析了双圆弧拟合的原理,并对逼近误差进行分析,满足了加工拟合曲线的要求。     

35CrMo旋转接头激光表面硬化技术的试验研究

用L9(34)正交试验法研究35CrMo旋转接头激光相变硬化工艺参数优化组合,分析了旋转接头激光相变硬化方法.试验结果表明:激光相变硬化层硬度比渗氮淬火提高了30%,耐磨性提高了1倍,表面残余应力为压应力;满足了旋转接头工作要求,为改进旋转接头表面处理方法提供了依据.     

厌氧消化系统中硫酸盐对重金属化学形态的转化作用

本文对城市污水处理厂污泥厌氧消化过程中不同浓度的硫酸盐对铜、锌、镍三种重金属化学形态变化的影响进行了分析研究。结果表明，硫酸盐的存在能够促进污泥中重金属向稳定的硫化物形态转变。     

重型柴油车加载减速工况烟度排放特性

应用加载减速工况排放测试方法对1500多辆在用重型柴油车进行了烟度排放测试,通过对试验结果进行统计分析,研究了车辆烟度排放值与车辆行驶里程、车龄、车辆质量、发动机吸气方式的关系,通过回归分析得出了烟度的排放值与车辆行驶里程、车龄、车辆质量的数学关系式,以及相应的相关系数。结果表明车辆行驶里程150000km以内,烟度的排放值随里程增大而增大,但150000~300000km段烟度值变化平缓;车龄从3年增长到10年,烟度排放值增长约40%以上;车辆烟度值随车辆总质量的增大而下降;增压式柴油机的烟度较自然吸气式柴油机烟度低10%以上。