烃氧化产物皂化后活性组分在油、水相的分配

用强酸酸化后测定乙醚抽出物酸量和酯量、溴甲酚绿两相滴定测定羧酸盐等方法研究了烃氧化产物皂化后活性组分在油、水相的分配。结果表明,在现行的用NaOH皂化烃氧化产物以制备水溶性石油磺酸盐的过程中有相当多的活性组分分配到油相;在水相和油相中均有大量羧酸酯存在,羧酸酯量远远超过羧酸盐量。     

Thermal design method of bayonet-tube evaporators and condensers

The paper describes an effectiveness-NTU design method of bayonet-tube evaporators and condensers. Including the effect of the wall superheat on the shell-side film coefficient, and using an energy balance on the tube, differential equations for the steady-state fluid temperatures are formulated. Because of the nonlinear nature of the governing equations, the fourth-order Runge-Kutta method is employed to the solution of the finite difference equations. The results are iterated with the combination of integration techniques. An upper bound to the numerical error being ±5% the fluid temperature distribution as well as the exchanger effectiveness are determined, and presented as a function of the Hurd number, the number of heat transfer units and the flow arrangement. For flow entering through the inner tube, the temperature distribution displays the occurrence of a minimum at a point other than the tube-tip of the exchanger. In an extension of the analysis, an effort is made to illustrate the deviation of the results obtained by uniform film coefficient from the present study, and the differences are outlined.     

AN EXPERIMENTAL AND NUMERICAL INVESTIGATION OF THE STARTING FLOW OF A UNIFORMLY ACCELERATING CIRCULAR CYLIINDER

The starting flow around a uniformly accelerated circular cylinder is investigatedby flow visualization techncque and solving N-S equations numerically in detail.The results ofthe starting flow are similar with those of the impulsively started one.At lower Re_α,numbers the“phenomenon a”is revealed;the“phenomenon β”appears at higher Re_α numbers,but withonly one secondary vortex.At the early stage of the starting vortex formation,the flow islaminar;at the later stage,the flow transforms into turbulent flow.The velocity distribution inthe flow field is measured with the multiwires installment.The calculational results are comparedwith the results of experiment,and both are in agreement with each other.     

自由飞行轨道解析解的中间轨道方法

本文给出了一组不仅能用于卫星轨道计算，同时也能用于导弹自由飞行轨道的中间轨道计算公式。引组公式的解与二体问题解有很好的可比性。由于导弹轨道与卫星轨道有很大不同，故计算中的各使用常数的取值范围也有很大不同。     

落脚河水电站引水发电系统的调节保证计算分析

水轮发电机组在运行中遇到启动、正常停机、增减负荷、事故甩负荷等工况变化时，经常会引起引水发电系统的水力过渡过程，所以在设计中必须通过调节保证计算以选择合适的导叶调节规律及其调节时间，从而优化压力引水系统的运行工况，使水电站的水工建筑物布置既经济合理又安全可靠。     

混凝土构件承载力计算的Excel实现

运用Excel软件,高效解决了混凝土结构计算中较复杂的圆形截面偏压构件的承载力计算问题。该编程计算方法同样适用于土力学、水力学、钢结构等领域。对于解决工程中的各种学科计算问题有着广阔的应用前景。     

Recursive calculation of ladder circuit frequency functions

It is shown how the transfer function as well as the input impedance and admittance of any linear time-invariant ladder circuit can be determined in closed form as frequency functions dependent upon the network element parameters. All elements of the ladder circuit must be explicitly specified by their frequency characteristics. The results are achieved with the aid of recursive algorithms. The outcome is demonstrated by means of an example.     

基于数字运算的PSD调理电路设计

介绍了基于数字运算的PSD调理电路思想及具体线路构造,该电路避免了模拟运算的缺陷,提高了精度和可靠性.     

工业建筑中钢结构的设计

钢结构已广泛应用于工业建筑中 ,本文叙述了工业建筑中钢结构的设计     

ZnO压敏陶瓷最佳掺杂含量的理论计算

从对电子薄膜材料研究中得到的最佳掺杂含量定量理论推广到ZnO陶瓷材料。该理论建立了电子薄膜材料的某一物理性能与晶体结构、制备方法和掺杂剂含量之间的联系，给出了一个能够拟合实验曲线的具有确定物理意义的抛物线方程。该方程的极值点确定了最佳掺杂含量与晶体结构和制备方法之间的定量关系，进而得到了一个掺杂最佳含量的表达式。系统地分析了ZnO压敏陶瓷的掺杂改性的实验结果，应用此表达式定量计算了ZnO压敏陶瓷的最佳掺杂含量，定量计算的结果与实验数据相符合。该理论也适用于其他薄膜材料最佳掺杂含量的理论计算。