Time and Temperature Factors in Construction of Rock Strength Criteria

Using the synthesis of the kinetic concept on solid strength and the Coulomb - Mohr strength theory as the base, the failure conditions taking into account the time and temperature factors are obtained.     

Ultrasonic properties of hexagonal ZnS at nanoscale

Higher order elastic constants have been calculated in ZnS at 300 K and 500 K following the interaction potential model. Ultrasonic attenuation, velocity and other related parameters have been calculated using the higher order elastic constants for the different size of the material at 500 K. The size dependency of the ultrasonic properties is discussed in correlation with elastic, thermal and electrical properties. It has been found that the thermal conductivity is the main contributor to the behaviour of the ultrasonic attenuation as a function of the size and the responsible cause of attenuation is phonon-phonon interaction. The semiconducting nature of ZnS film has been achieved with the study of size variation of thermal relaxation time and ultrasonic attenuation.     

基于自然地理形态的道路测设及其曲线方程的拟合

在山区村镇及风景旅游名胜区的建设中，其道路的曲线测设，往往要基于自然地理形态进行，也就是路径的选择，有时具有不可选择性，且要求与实地具有最大的符合性。因此，其测设的作业方法不同于一般意义的道路测设；其曲线方程的建立，也是极其困难的。本就基于自然地理形态的道路测设工作的曲线类型的选择、曲线的拟合方法、曲线方程的建立及其数据的计算，提出了利用CAD技术进行曲线拟合、曲线方程的建立、曲线计算的实用技术方法。     

用于皮带及链传动的一种恒张力张紧装置

指出了皮带及链传动现有张紧方法的缺点，设计了一种结构简单、工作可靠的用于皮带及链传动的恒张力控制装置，该装置能自动调整压在皮带或链上的力，在很大挠角范围内保持其张力基本恒定。     

高坝洲电站碾压混凝土纵向围堰拆除爆破设计与实践

介绍了高坝洲电站碾压混凝土下游纵向围堰现场爆破试验成果,在分析爆破试验效果的基础上进行碾压混凝土围堰拆除爆破设计,详细分析了拆除爆破实施效果及主要影响因素.     

基于人文关怀的信号配时方法研究

在传统的信号配时中，都是以减少车辆的总延误为目标，这样并不能很好地体现出整个社会中人的时间价值。现以减少所有通过交叉口的出行者的总延误为目标，在传统的信号配时方案的基础上，提出了一套新的配时方案，同时以减少全部出行者的总延误时间为目标给出了相应的延误评价公式，最后以杭州市文一路-古翠路口的实测交通数据进行分析，论证了本配时方案的有效性。     

一种简单的S参数去嵌入技术

介绍了在低成本夹具上，任意微带结构二端口网络S参数去嵌入的方法；该方法用于获取放大器模块的S参数，根据这些参数设计的C波段的放大器实测结果与仿真一致。     

控制张紧力,延长钢丝绳芯胶带使用寿命

钢丝绳芯胶带是一种优质高效的运输带 ,影响它使用寿命的因素很多。本文重点介绍了张紧力对钢丝绳芯胶带的影响 ,阐述了实际工作中如何及时调节张紧力 ,并提供了几种调整张紧力的方法。     

Non-steady-state model for kinetics of free radical polymerization, 4. Direct thermal initiation

This paper deals with the non-steady-state kinetics of direct thermal initiated polymerization. The initiation is assumed to be a bimolecular reaction of the monomer. The relationship between the radical concentration and the monomer conversion is rigorously derived. In further treatment a few very close approximations are introduced based on the fact that the number of monomer molecules reacting in the initiation step is much less than that consumed in the propagation step for a process producing high polymer, and the value of the rate constant for propagation or chain transfer is much lower than that for chain termination. Expressions for various molecular parameters, such as molecular weight distribution, number-average and weight-average degrees of polymerization, and dispersity, are given. Several numerical examples are provided.     

旋波媒质基本参数的一种测试方法

本文提出了直接利用旋波材料板的Ｓ参数获得其基本参数的方法。通过自由空间测量旋波材料板的反射场和透射场，可以反演得到媒质的复介电常数、复磁导率、旋波量以及透射场的轴比和旋转角，测试程序简单，结果精度高。