Do the VOCs that evaporate from a heavily polluted river threaten the health of riparian residents?

To understand the potential threat of volatile organic compounds (VOCs) to the health of residents living close to a heavily polluted river, this study investigated the species and the concentration of VOCs evaporating from a river and surveyed the health condition of the nearby residents. Air samples were taken seasonally at the upstream, midstream, and downstream water surfaces of the river, and at different locations at certain distances from the river. These samples were analyzed qualitatively and quantitatively through gas chromatography and electron capture detector (GC/ECD) for chlorinated organic compounds, and through gas chromatography and flame ionization detector (GC/FID) for ordinary hydrocarbons. The health data obtained from valid health questionnaires of 908 residents were analyzed through Statistical Package for Social Science (SPSS) software. Twenty-six species of VOCs were identified in the environment adjacent the river, many of which are carcinogenic or believed to be carcinogenic to humans. However, results of this study shows that the VOCs evaporating from the polluted river have not been definitively identified as a major factor of cancer in the residents. However, the risk of suffering from certain chronic diseases may increase in residents living less than 225 m away from the river due to the high levels of evaporated VOCs. Residents living less than 225 m away from the river and with nearby specific industries are 3.130 times more at risk of suffering from chronic diseases than those with no nearby specific industries.     

高腐蚀率钢筋混凝土梁抗弯性能研究

对4根未腐蚀和16根腐蚀钢筋混凝土梁进行抗弯试验,研究重复荷载下高腐蚀率对钢筋混凝土梁变形、裂缝、承载力及破坏机理的影响。提出重复荷载下受腐蚀钢筋混凝土梁承载力计算公式。同时拟合出钢筋腐蚀率对钢筋混凝土受弯开裂的影响,并提出受腐蚀梁在重复荷载下的开裂荷载计算公式。     

浅谈解决三相变压器直流电阻不平衡率的问题

通过对三相变压器直流电阻不平衡率实例的分析,总结出了解决三相变压器直流电阻不平衡率的方法。     

浅谈临时用电市场的开拓

临时用电市场是电力公司非常优质的市场,发展临时用电市场可给供电企业带来明显的效益,也有助于提高市场占有率,同时为客户提供了生产电力,降低了生产成本。临时用电比较分散、隐蔽,信息不易掌握,供电存在难度。以甘肃省为例,通过分析临时用电的特点及存在的问题,提出了适合于开拓临时用电市场的具体措施。     

中国电力工业CO2减排战略分析

对电力工业主要的碳减排方式的减排成本、减排潜力及对化石能源消耗量的影响进行分析对比,并在此基础上对中国电力工业的碳减排战略进行了分析预测.研究结果表明:各种减排方式综合应用是我国电力工业碳减排的必然趋势,其中节能、核电以及水电、风电和太阳能发电等可再生能源发电在2050年的CO2减排潜力均可达到10亿吨以上,且可以节约大量化石能源,是应优先发展的重要减排技术.     

基于水下钢球法的水工混凝土磨损影响因素研究

为了预测水工泄水建筑物抗冲磨混凝土在含推移质水流作用下的使用寿命,需了解磨损介质粒径和水流速度对混凝土破坏程度的影响.为此,分别采用12.6mm、19.0mm、25.4mm、30.0mm四种直径的钢球作为磨损介质,并在近底水流速度约1.8m/s和1.5m/s两种水流速度下,进行两种强度等级抗冲磨混凝土的水下钢球法试验....     

高速补充信道对cdma2000-1x前向链路功率分配的影响

分析了cdma2000-1x系统的前向信道发射功率分配。通过仿真试验及理论推导，给出了导频信道和业务信道信号质量之间的相互依赖关系并绘出导频信号和业务信道之间的相关性曲线：根据这种相关性曲线，从而发现使总发射功率最小的最佳导频功率；最后提出并分析了高速补充信道对cdma2000-1x前向链路功率分配的影响。     

PDP荧光粉浆料用有机载体的研制

使用混合溶剂,得到了具有层次挥发性的PDP(等离子体显示板)荧光粉浆料用有机载体,研究了有机载体对烧结后荧光粉亮度的影响。结果表明:使用了载体的荧光粉浆料烧结后亮度比达98%(147nm),包膜荧光粉亮度比可达106%(147nm)。此载体可以用于配制PDP荧光粉浆料。     

多串口转GPRS组网方式的基站监控应用

在无有线传输资源的移动基站中,基站内智能设备通过多串口转GPRS传输方式实现了对基站的远程监控,提高了监控覆盖率。GPRS技术使用方便,成本较低,可以稳定地传送数据,有利于大规模网络的建立。     

基于数字平台罗经的舰载雷达大惯量伺服系统设计

介绍了一种在低数据率的数字平台罗经接口下某舰载雷达伺服系统对大惯量稳定平台进行稳定跟踪的设计方法。该伺服系统采用全数字的伺服控制模块作为其位置环的控制核心,利用伺服电机驱动器实现伺服电机速度电流双闭环,组成了一个有良好位置控制性能的数字伺服系统。