铜的离子浮选和溶剂浮选

以浮选过程中存在各种离子平衡为基础,从理论上推算出浮选Cu~(2+)稀溶液的最佳pH范围,并为浮选实验所证实。将C_(12)H_(25)SO_4Na(NaLS)与Cu(LS)_2作为理想的表面活性剂混合物,通过表面张力测定,算得离子对平衡常数K与Cu(LS)_2的表面过剩摩尔分数X_(Cu(?)LS_z)~3的值分别为1.77×10~3与0.917。在pH=5.6条件下,以铜萃取剂加在溶剂中的溶剂浮选,比离子浮选和溶剂萃取具有更佳的分离效率,其效率可达91.6%。     

电弧法获得的几种奇异碳纳米管的研究

用电弧法制备碳纳管时,在阴极沉积物中,伴随大量正常的离散碳纳米管的产生,发现了孪生碳纳米管、菱形碳纳米管、“Y”形短管和碳纳米纤维等几种奇异的碳纳米形态。给出了这些奇异碳纳米管的透射电镜（TEM）照片,对它们的生长、闭合过程进行了研究,认为碳原子流、电场等因素的影响是奇异碳纳米管形成的关键,借助碳纳米管以内层为模板的开口生长模型,可以定性地理解它们的形成过程及生长机理。     

山西省煤矿开采对地质环境的影响及防治措施

本文在对山西省煤炭资源进行概述的基础上,总结了煤矿开采对山西省地质环境的影响,并将其划分为四个方面:煤矿开采对矿区地表稳定、水资源、土地资源和采场环境的影响.具体表现为:矿区地面裂缝、地面塌陷,滑坡、崩塌、泥石流,地面沉降,煤层自燃;地下水疏干,地表水污染及漏失;矿区荒漠化;矿井突水、瓦斯爆炸等.最后介绍了各煤矿地质灾害的防治措施以及山西省煤矿治理工作的进程.     

A complete sequence and comparative analysis of a SARS-associated virus （Isolate BJO1）

The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-assoclated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs.We report the complete genome sequence and comparative analysis of an isolate (B J01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 20RFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS-associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to be involved in the immunoreactions between the virus and its host.Two amino acid changes have been detected in the M protein,which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides no evidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of other possible SARS-related pathogen(s).     

涡轮泵转子-石墨密封系统的振动特性

针对液体火箭发动机涡轮泵中转子-石墨接触式密封系统的接触摩擦问题,建立了涡轮泵转子-石墨密封系统的弯扭耦合动力学方程.采用Runge-Kutta法得到不平衡力激励下的振动响应,并分析了压紧力对转子振动响应的影响.响应频谱分析结果表明,在石墨密封的作用下,即使转子偏心量较小,转子振动也会出现组合频率振动和零频振动等典型弯扭耦合振动现象.随着压紧力的增大,转子振动谱图中出现连续谱及零频振动,在整个频域范围内转子出现组合共振.转速的升高和压紧力的增大都会导致转子振动趋于低频振动.研究结果表明,石墨密封摩擦作用增强了转子弯曲和扭转振动的耦合,并可能引发转子系统失稳.     

基于无线Mesh接入服务技术的校园网设计与实现

无线Mesh网简称WMN,是一种新型的无线通信网络;这是一种高容量、高速率、多跳的分布式宽带无线网络.以某体育学院校园网工程为背景,对原有校园网进行分析,提出了全新的整体规划,包括各层交换机和路由器的配置、无线接入的配置等;设计中采用三层交换结构,即接入层、汇聚层和核心层,在各个层上采用相应的配置策略;新的设计提高了校园网数据交换速率和整体性能.     

硅烷自组装膜对PPy固体铝电解电容器的影响

通过对比在固体铝电解电容器多孔性绝缘Al2O3膜表面是否进行硅烷偶联剂预处理后化学聚合得到的导电聚吡咯（PPy）薄膜的连续性、附着性与电导率以及所得PPy固体铝电解电容器的性能指标,探讨了硅烷自组装膜对PPy薄膜与PPy固体铝电解电容器性能的影响及硅烷自组装膜在多孔性Al2O3膜表面的形成机理与PPy薄膜在硅烷自组装膜上的成膜机理．PPy薄膜的电导率从5．4s·cm-1提高到了16．6S·cm-1,PPy固体铝电解电容器的损耗角正切tgδ≤0．06（120Hz,20℃）,漏电流IL≤〈0．04CV（或3μA）．     

自由基与纸浆漂白(Ⅰ)——自由基的产生及其在漂白中的作用

论述在纸浆的常用漂白剂漂白过程中自由基的产生、自由基与过渡金属离子的关系,自由基的漂白作用及其对碳水化全物的影响等。     

Delayed drainage of aquitard in response to sudden change in groundwater level in adjacent confined aquifer: Analytical and experimental studies

The problem of the groundwater dynamics and water balance of a confined aquifer in the aquifer system has been solved in previous studies, whereas that in the aquitard adjacent to the confined aquifer has seldom been considered. In reality, the groundwater dynamics of the aquitard are closely related to the exploitation of groundwater resources, groundwater contamination, underground storage utilization and land subsidence. In this paper, an analytical solution is derived to describe the drawdown variation in the aquitard when the head in the adjacent confined aquifer declines by a constant value. The characteristics of groundwater dynamics and water balance of the aquitard are analyzed using a dimensionless analytical solution. There is obvious delayed behavior in the response of groundwater dynamics in the aquitard, which is characterized by the delay index t0. The delayed behavior in the response of groundwater dynamics is not only dependent on the properties of the aquitard, but also proportional to the square of the thickness of the aquitard. The law of the delayed release of water is described in terms of the ratio of the delayed release of water. A water balance equation for the aquitard is established. Three stages of the water balance and the corresponding characteristics are presented with the water balance curves of the aquitard. The analytical solution is given to analyze the flux per unit horizontal area of the aquitard. The hydrogeological parameters of the aquitard, namely the hydraulic conductivity, specific storativity and hydraulic diffusivity, are estimated according to type-curve fitting between the analytical solution and observed flux. The parameters are identified and validated in an experiment.     

碳钢高速车削中基于量热法的切削热分配

介绍了基于量热法的碳钢高速车削切削热在切屑、工件、刀具及环境中的量化分配.采用水作为收集切削热的媒介,通过自行设计的适配于高速车床的集屑容器以及分别收集工件和刀具热量的容器,在封闭式高速车削条件下测得各容器中水和承载物的温度变化,从而计算出传入切屑、工件、刀具及环境中的热量和总热量以及热流量.通过测量切削力和设定切削速度,得到主切削力的功率.将算出的总热流量与主切削力的功率相比较,评判用量热法测量切削热时的精确程度.