大源渡水电枢纽工程纵堰拆除控制爆破的安全监控与施工

介绍了大源渡水电枢纽工程纵堰拆除爆破中所采取的减震措施;对爆破过程进行了动态监控。试验表明, 爆破震动监测可以及时反馈信息, 指导设计与施工, 有助于工程施工安全。     

高发射率金属氧化物涂料的制备与性能

以改性粘结剂、Cr2O3、MnO2为主要原料,辅以ZrSiO4、Fe2O3、MgO等多种氧化物,分别在950、1100和1250℃下保温2 h,水淬急冷出料,然后采用高温熔烧法在不锈钢表面制备高发射率涂层。采用X射线衍射仪、扫描电镜、红外辐射测量仪对涂料样品物相、形貌和辐射性能进行了测试表征,并测试了涂层抗热震性能。结果表明:不同温度下煅烧生成不同的尖晶石结构,1250℃煅烧后生成多种复杂尖晶石及其固溶体结构,表现出最佳的红外辐射性能,在1～22μm波段法向发射率可达0.90;涂层试样的抗热震次数可达25次(室温至800℃),表明涂层结合强度较高。     

Effect of granite gravel content on improved granular mixtures as railway subgrade fillings

The improved granular mixtures are widely used as the fillings of railway 8ubgrade, and in order to investigate the effect of coarse grain content on granular mixtures, a series of field tests were conducted. The experimental results indicate that the permeability coefficient increases significantly with the increment of granite gravel content, especially in the range of 60%-70%. Thcrc exists a coarse grain content limit defined as 53%-58.5% to reform the permeable granular skeleton. Beyond this limit, the permeable granular skeleton is efficiently formed, and the macro pores between the separate gravels are partially filled, which is the explanation lbr the permeability increase. The investigations indicate the subgrade resistance modulus （ks0, Ev2, and Evd） depends on the granite gravel content, and the resistance modulus increases significantly beyond granite gravel content of 50%. The skeletons of granitc gravel clayey sand mixture change in the long-term deformation objected to the train-induced dynamic load, which involves three main repeated and circular deformation stages. Generally, the long-time deformation is explained as the gravel crushing and filling the internal porous space with crushed gravel fragments. Through these investigations, the C40-G60 or C30-G70 is recommended as an optimum soil mixture for the good permeability and high resistance modulus.     

窑尾排风机温度检测报警电路的误动作分析

水泥生产中有很多大功率、高压、高频的设备，它们在启动、运行过程中往往会产生很多高频电磁波，对附近的自动化仪表检测装置产生影响，使其发出错误的检测报警信号，导致保护装置误动作，从而造成生产设备的误停机。下面以窑尾排风机为例，介绍我们的处理方法。     

拓扑学的新应用——三维块体的几何识别

描述了通过岩体中不连续面交叉形成多面块体的一种新方法，该方法体现了拓扑学单纯同调论原理在形成多面体中的用途，给出详尽的计算公式和实施步骤，几何问题的代数转化使整个融会体现了该方法的新颖性。     

Deformation characteristics of coarse-grained soil with various gradations

By using large scale triaxial shearing apparatus, consolidated-drained shear tests were conducted on coarse-grained soil with different gradations. In order to describe their deformation rules, three main characteristics of tangent Poisson ratio curves were summarized and the reason was revealed by dividing the movement of soil particles into two kinds： the movement of fine particles and the movement of coarse particles. Then, a volumetric strain expression and a tangent Poisson ratio expression were put forward, and two defects of widely used Duncan-Chang model were fixed. Results calculated from them agree well with test results. There are three parameters, namelyL,G andF, in this new model. ParameterL reflects the dilatancy of a specimen andL=4 can be used as a criterion to estimate whether a certain kind of soil has dilatancy quality or not. ParametersG andF relate to the initial slope of tangent Poisson ratio curves, andG=F=0 indicates a special situation which happens in dense granular material of the same diameter. Influences of various gradations on volume deformation are mainly reflected in parameterL which is smaller when there are more gravels in specimens.     

基于C51控制的无线电子标签设计与应用

针对传统大型超市商品信息显示方法和仓储拣选作业流程的分析,提出了一种利用C51单片机和无线通信技术,通过LCD实现电子标签显示商品信息的方案.详细地介绍了系统的硬件结构和软件设计思想,叙述了接收模块的程序设计方法并给出了程序流程图和源代码,实践结果表明,该系统抗干扰性好,实现简单,提高了商品的管理效率,并大大降低了拣货的出错率,应用前景十分广阔.     

自适应遗传算法在电厂主汽温控制系统优化中的研究与应用

电厂中的热工系统是一个复杂的系统,由于其特有的复杂性,使得模型的获取有一定的难度．PID调节是热工系统最主要的控制策略,它直接影响机组的安全、经济运行．自适应遗传算法作为一种智能优化算法,它是在解空间进行高效启发式搜索,而非盲目地穷举或完全随机搜索,应用遗传算法对主汽温系统控制器参数进行优化,实验表明,应用遗传算法优化控制器参数,能够获得令人满意的效果．     

Effects of stress conditions on rheological properties of granular soil in large triaxial rheology laboratory tests

In order to study the rheological properties of red stone granular soil,a series of rheological experiments were executed on large tri-axial rheological apparatus.Under 100,200 and 300 kPa confining stress conditions,the rheological tests were carried out.These experiment results showed that the stress conditions,especially the stress level were the critical influencing factors of the rheological deformation properties.Under the low stress level(S=0.1),the granular soil showed the elastic properties,and there was no obvious rheological deformation.Under the middle stress level(0.20.8) creep curves showed the non-linear viscous plastic rheological properties.Especially,under the stress level of S=1.0,the accelerated rheological phase of creep curves occurred at early time with a trend of failure.The stress level had obvious effects on the final rheological deformation of the soil sample,and the final rheological deformation increments nonlinearly increased with stress level.The final rheological deformation increment and step was little under low stress level,while it became large under high stress level,which showed the nonlinearly rheological properties of the granular soil.The confining pressure also had direct effects on final rheological deformation,and the final rheological deformation linearly increased with confining pressure increments.