钢管混凝土的等效本构关系研究

在总结现有钢管混凝土本构关系分析的基础上,将钢管混凝土简化为同一尺度的横观各向同性体来研究,并在弹性条件下利用应变能相等原理得到了宏观弹性系数,同时根据试验结果假设进入弹塑性阶段后各模量为二次抛物线变化,建立了钢管混凝土这种组合结构新的等效本构关系.并结合具体算例研究了弹性条件下材料强度变化和含钢率对各模量的影响,同时与前人的研究结果进行了比较,结果表明,该本构关系具有理论依据明确,参数易确定,能很好地反映组合构件材料物理性能的优点,为钢管混凝土结构进一步进行数值分析奠定了基础.     

The effect of some instrument operating conditions on the x-ray microanalysis of particles in the environmental scanning electron microscope

The objective of this investigation was to evaluate the practical effects of electron beam broadening in the environmental scanning electron microscope (ESEM) on particle x-ray microanalysis and to determine some of the optimum operating conditions for this type of analysis. Four sets of experiments were conducted using a Faraday cage and particles of copper, glass, cassiterite, andrutile. The accelerating voltage and chamber pressure varied from 20 to 10 kV and from 665–66 Pa (5.0 to 0.5 torr), respectively. The standard gaseous secondary electron detectors (GSED) and the long environmental secondary dectectors (ESD) for the ESEM were evaluated at different working distances. The effect of these parameters on the presence of artifact peaks was evaluated. The particles were mounted on carbon tape on an aluminum specimen mount and were analyzed individually and as a mixture. Substrate peaks were present in almost all of the spectra. The presence of neighboring particle peaks and the number of counts in these depended upon the operating conditions. In general, few of these peaks were observed with the long ESD detector at 19 mm working distance and at low chamber pressures. More peaks and counts were observed with a deviation from these conditions. The most neighboring peaks and counts were obtained with the GSED detector at 21.5 mm working distance, 10 kV accelerating voltage, and 665 Pa (5.0 torr) chamber pressure. The results of these experiments support the idea that the optimum instrumental operating conditions for EDS analysis in the ESEM occur by minimizing the gas path length and the chamber water vapor pressure, and by maximizing the accelerating voltage. The results suggest that the analyst can expect x-ray counts from the mounting materials. These tests strongly support the recommendation of the manufacturer to use the long ESD detector and a 19 mm working distance for EDS analysis. The results of these experiments indicate that neighboring particles millimeters from the target may contribute x-ray counts to the spectrum.     

考虑风电接入和气电转换的综合能源系统日前区间优化

针对气电综合能源系统优化调度中未充分挖掘可调度因素、未充分考虑风电预测误差不确定性的现状,研究含风电的气电综合能源系统日前区间优化调度方法。首先,基于区间数学对风电出力的不确定性进行区间描述,综合考虑抽水蓄能、气电双向转换以及需求响应等资源和技术,并用区间数学表示优化目标和优化约束,构建含高比例风电的气电综合能源系统日前优化模型,综合优化系统的经济性、环保性。然后,基于区间序关系和可能度的方法将区间优化模型转化为确定性优化模型,继而采用Jaya算法进行求解,保证求解的高效性和解空间的可行性。最后,进行算例分析,仿真结果验证了综合利用抽水蓄能、气电双向转换以及需求响应等要素对系统进行区间优化,能取得优化效果上的优势,并能为系统调度人员提供风电不确定度对系统优化影响的信息。     

利用铜尾矿烧制水泥熟料的技术研究

利用给定铜尾矿在系统分析的基础上,掺加其它一些原料,在实验室烧制高标号水泥熟料。     

用神经网络求解TSP的一种改进算法

对利用神经网络求解ＴＳＰ问题的算法进行了改进,在保持算法优点的基础上,使得所需神经元的数目减少,对提高计算效率以及神经网络的硬件实现有参考价值。     

船舶最小能量消耗的控制指标

本文介绍了一种船舶自动航行时,使推进能量消耗为最小的控制指标,它同目前存在的各种指标相比,具有一定的优点.     

对皖北地区500kV输电线路耐雷性能的研究

根据安徽电网皖电东送通道8条500 kV线路的运行情况,结合皖北地区500 kV输电线路跳闸原因,分析输电线路设备耐雷状况,提出了综合防治措施,以便改进皖北地区500 kV线路的耐雷性能,提高其安全稳定运行水平。     

循环流化床锅炉启动能耗大的原因分析及对策

针对平朔电厂300 MW循环流化床锅炉点火能耗大的问题,详细分析了现有的点火状况以及影响启动能耗的因素,并在床料量的选取、点火一次风量的调整、油枪的出力选取、投煤温度点的选取以及启动时间上进行了相应的调整,调整后的运行方式在实际运行中得到了很好的应用,并取得了良好的经济效益。     

基于超大电容器储能的独立光伏系统的建模研究

Eestor电容功率密度大、能量密度高且使用安全无污染,是理想的储能器件。设计了一种基于Eestor电容储能的独立光伏系统的系统模型,建立其小信号模型,用Simulink仿真对其运行特性进行了分析,结果表明,系统在光伏输入功率大幅波动以及负载突变时具有很好的稳定性,为其进一步应用于可再生能源发电系统提供了参考。     

我国发电行业能效状况分析

发电行业在完成能源转换的同时,也是自身消耗能源较大的重点行业。文章简要介绍了我国发电行业的节能成绩和效益,分析了不同机组能效情况和主要技术经济指标,指出了“十一五”发电能效影响因素和节能目标,提出了主要技术政策措施建议。