深过冷Cu-20Wt%Pb亚偏晶合金的凝固行为

采用熔融玻璃净化和循环过热相结合的方法，使Cu-20wt％Pb亚偏晶合金获得了208K的深过冷，在宽过冷范围内研究了Cu-Pb亚偏晶合金的组织演化规律。结果表明，过冷合金熔体初生相为α(Cu)，在0～146K的过冷度范围内，均有两次再辉现象；在183～208K的过冷范围内，只出现一次再辉。当△T≤98K时，合金凝固组织为粗大枝晶α 枝晶间Pb相；当116K△≤T≤146K时，凝固组织已无明显的枝晶形貌，组织由细密α基体 细小的Pb颗粒组成；当△T≥183K时，凝固组织与中等过冷度下的组织相似，只是Pb相更细小，分布更均匀。当△T≥133K时试样出现裂纹。     

The fate of injectant coal in blast furnaces: The origin of extractable materials of high molecular mass in blast furnace carryover dusts

The aim of the work was to investigate the fate of injectant coal in blast furnaces and the origin of extractable materials in blast furnace carryover dusts. Two sets of samples including injectant coal and the corresponding carryover dusts from a full sized blast furnace and a pilot scale rig have been examined. The samples were extracted using 1-methyl-2-pyrrolidinone (NMP) solvent and the extracts studied by size exclusion chromatography (SEC). The blast furnace carryover dust extracts contained high molecular weight carbonaceous material, of apparent mass corresponding to 10⁷?10⁸ u, by polystyrene calibration. In contrast, the feed coke and char prepared in a wire mesh reactor under high temperature conditions did not give any extractable material. Meanwhile, controlled combustion experiments in a high-pressure wire mesh reactor suggest that the extent of combustion of injectant coal in the blast furnace tuyeres and raceways is limited by time of exposure and very low oxygen concentration. It is thus likely that the extractable, soot-like material in the blast furnace dust originated in tars is released by the injectant coal. Our results suggest that the unburned tars were thermally altered during the upward path within the furnace, giving rise to the formation of heavy molecular weight (soot-like) materials.     

Influence of overpressure on coalbed methane reservoir in south Qinshui basin

In theory, from the high temperature and pressure during the coal generating gas to the present low temperature and pressure of coalbed methane reservoir, the accumulation of coalbed methane was from oversaturated to undersaturated. The gas content of the coalbed methane reservoir in the south Qinshui basin was 12-35.7 m3/t. According to the isotherm and measured gas content of No. 3 coal, the adsorbed gas content in some wells was highly saturated and oversaturated, which was hard to theoretically understand. In addition, there were no thermogenic and biogenic gases at the late stage in the south Qinshui basin. This article proposed that the overpressure was the main reason for the present high saturation of the coalbed methane reservoir. In early Cretaceous, the coalbed methane reservoir was characterized by overpressure and high saturation caused by gas generation from coal measure source rocks. In late Cretaceous, the coalbed methane reservoir was rapidly uplifted, and with the temperature and pressure decreasing, the pressure condition of adsorbed gas changed from overpressure to normal-under pressure, which resulted in the high saturation and gas content in the present coalbed methane reservoir.     

基于输出的供应链分销阶段绩效改进方法

总结了标杆学习中目标企业选择和学习途径确定的方法·研究了基于输出的绩效评价和改进的标杆方法,给出了特定输出增长等定义和有关数据包络分析(C2GS2)的扩展模型·模型中所有被评价企业均视为具有相同输入、输出的决策单元·指出最小特定输出增长为绩效改进的最短路径,所对应企业为最佳标杆学习对象·在供应链分销阶段,该方法更易于操作,企业可保持现有投入,通过提高输出元素水平改进绩效·     

高师数学"方法论教学法"的实践与探索

高师数学的教学改革，应有自己的特色，以现代教育理论、数学方法论以及高师数学专业学生应具备的数学思想方法、能力、素质等要求为依据；给出了高师数学“方法论教学法”的理论体系、系统设计、教学模式、教学原则、实施方案，并对实验效果和存在的问题进行了分析．     

带机器准备时间的同类机在线与半在线排序问题

研究带机器准备时间的m台同类机(uniform machines)在线和半在线排序问题，目标函数为极小化最大机器(工件)完工时间。对于在线情形，证明了LS算法的最坏情况为ρ=｛（1 √5）/2，m=2,1 √2m-2/2,m≥3，并且当m=2，LS算法是最好的近似算法；当m=2，3，…，6时界是紧的，特别地，当s1=s2=…=sm-1,sm≥l时，证明了LS算法的最坏情况界为ρ=｛（1 √5）/2，m=2,3-4/m 1,m≥3，而且界是紧的；对于已知加工时间递减的半在线排序问题，证明了LS算法的最坏情况界为2—2/(m 1)。     

HDTV视频同步与消隐时序控制信号的CPLD设计

ATSC HDTV视频输出采用了SMPTE的相应标准．将像素计数与行计数相结合，采用统计行分类编码的算法对SMPTE274M、SMPTE296M、SMPTE293M和SMPTE295M标准的同步与消隐时序控制信号进行了多平台的仿真分析，并在ALTERA公司的EPM7128上最终实现了本设计．     

数学建模在对企业经营业绩评价分析中的应用

本论文通过CT总公司所属9个分公司财务指标即：财务效益状况指标，资产营运状况指标，偿债能力状况指标，发展能力状况指标和稳固程度状况指标5个方面的财务状况数据，采用数理统计方法进行数据分析，建立数学模型，设定了评分办法，给出了评分标准。做出了物资总公司所属9个分公司1998年，1999年，及2000年的经营业绩（量化）评价结果。     

高压受限电弧等离子体发生器实验研究

电热化学发射中，等离子体发生器的放电是电能转化为热能的重要阶段。该文在自由喷射等离子体发生器实验装置上分别对不同毛细管几何参数、不同贮能水平以及不同毛细管材料等3种情况进行了放电实验研究及分析，得出了负载效率、峰值电流、平均电阻等测量参数与贮能水平和毛细管几何参数之间的关系。     

21世纪先进发射药:低敏感高能发射药(1)--新材料和新实验技术

现代先进武器系统对弹药提出了大威力和高生存能力的要求，研究开发低敏感高能发射药必将成为21世纪发射药及其装药发展的大趋势。该文讨论了低敏感高能发射药的研究背景和意义。详细讨论和分析了发达国家在低敏感高能发射药领域涉及的新材料和新实验技术方面的最新研究进展和成果。指出了我国正处于跨越低易损性发射药的发展阶段，可直接制定并实施兼具低易损性和高能特点的低敏感高能发射药的研究计划。