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71.
电器实验室在对电器产品实施安全性能检测的过程中,实验室本身存在着安全和环境污染问题。如何对实验室的日电器实验室在对电器产品实施安全性能检测的过程中,实验室本身存在着安全和环境污染问题。如何对实验室的日常运作进行安全和环境的有效监控,对于保护实验室仪器设备和生命财产安全,以及试验人员的健康,具有重要的意义。 电器实验室安全和环境问题涉及但不限于防火、防烫伤、防暴、防触电、防机械伤害、防淋水、防盗、限制区域的禁入、仪器设备的保护、试验负荷控制、环境温度、湿度、电网电压、谐波畸变、噪音、有毒有害气体、电磁渡污染等诸多方面。本文针对电器实验室存在的一些主要安全和环境问题,从经济和技术可行性方面研究有效解决方法,并提出一种利用现代科技实现远程综合监控的方案。  相似文献   
72.
轨道清扫器是起重机械上重要的安全防护装置之一.对于桥、门式起重机而言,因其轨道附近堆积物料复杂,轨道清扫器的设置与工作状况往往直接影响整机的安全.本文笔者探讨了传统轨道清扫器形式及其失效模式,自主研发的新型起重机械轨道清扫器能够很好的起到轨道清扫和避免运行车轮脱轨等危险事故地发生,保证了起重机械使用过程中运行的可靠性和...  相似文献   
73.
赵新 《环境技术》2006,24(2):39-42
中国是一个电子电器生产大国,广东又是国内家电等电子电嚣产品生产和出口的大省,是全球最大的制造基地和出口基地之一.随着家电等电子电器产品的无铅化要求,我国电子电器生产商将面临严峻的考验.本文对此进行了分析,提出了应对措施.  相似文献   
74.
The increase of electrical resistance (ER) and energy consumption (EC) during the later stage of dewatering is a major problem hindering the development of electro-dewatering (EDW) technology. As the variations of sludge characteristics are significant during the EDW process, the relationships between sludge characteristics and ER and EC during EDW remain unclear. In this study, the effects of moisture content (MC), thickness, pH, conductivity, zeta potential, temperature, and gas volume on the ER and EC during the EDW process were statistically investigated using correlation and multiple linear regression analyses. Herein, the results showed that the ER of the sludge near the anode was primarily affected by pH, whereas the sludge near the cathode was primarily affected by the MC and conductivity. Further, sludge temperature and conductivity were the most reliable indicators to predict the EC near the anode and cathode, respectively. The results of this study provide theoretical guidance useful for solving the increase of ER and EC during the later stage of the EDW process.  相似文献   
75.
电源环境应力筛选试验自动测控系统研究   总被引:1,自引:1,他引:0       下载免费PDF全文
曹金洲 《装备环境工程》2013,10(6):41-44,59
目的设计开关电源环境应力筛选测控系统。方法运用LabVIEW对仪器进行自动控制。结果实现了仪器控制,数据采集、监视与存储,数据回放等功能。结论测控系统运行稳定,操作简便,数据获取和处理便利。具有硬件配置简单、易维护,软件开发灵活等特点。  相似文献   
76.
Surface modification by material transfer during electrical discharge machining (EDM) has emerged as a key research area in the last decade. Material may be provided to the machined surface of the workpiece by the eroding tool electrode or by using powder-mixed dielectric. Breakdown of the hydrocarbon dielectric contributes carbon to the plasma channel which may also cause surface modification. The present work has investigated the response of three die steel materials to surface modification by EDM method with tungsten powder mixed in the dielectric medium. Taguchi experimental design technique was used to conduct the experiments on each work material independently. Peak current, pulse on-time and pulse off-time were taken as variable factors and micro-hardness of the machined surface was taken as the response parameter. X-ray diffraction (XRD) and spectrometric analysis show substantial transfer of tungsten and carbon to the workpiece surface and an improvement of more than 100% in micro-hardness for all the three die steels. Presence of tungsten carbide (WC and W2C) indicates that its formation is taking place in the plasma channel. Machining parameters for the best value of micro-hardness for each work material were found to be the same.  相似文献   
77.
Vetiver (Vetiveria zizanioides) has not been widely introduced in arid and semi-arid regions where irrigation, fertilization, and salinity are important factors in plant growth. The main objective of this study was to determine the response of vetiver to fertilization (fertigation) and salinity and their interactions under irrigated conditions. The experiment was conducted in a greenhouse in 10-L pots. Combined effects of three nutrients concentrations and three salinity levels of electrical conductivity (EC) 1, 3 and 6 dS/m in the irrigation water on growth and transpiration of vetiver plants and the content of different elements in their foliage were studied. Similar contents of 3.7 g/kg Na, 5.77 g/kg Ca and 2.55 g/kg Mg were found in the foliage of all the plants irrigated with the different fertilizer and salinity levels. Concentrations of 59 mg/L N and 36.1 mg/L K in the irrigation water were sufficient for vetiver plants needs at the different salinity levels tested. The salinity threshold (the maximum EC in the soil solution that does not cause a significant yield reduction) for vetiver was between 3 and 6 dS/m. A concentration of 15.2 mg/L P in the irrigation water was the optimum value for vetiver growth in the three salinity levels, resulting in an average content of 5.95 g/kg P in plant foliage. It is suggested that vetiver is sensitive to excess P (>8.66 g/kg). Increasing EC in the irrigation water to 6 dS/m decreased plant foliage biomass mainly due to an increase in the osmotic potential of the irrigation water and high Cl concentration in the foliage.  相似文献   
78.
目的针对隔离/接地开关传动轴表面维护涂层展开测试研究,并对其后续维护提出相应措施,希望通过加强检修维护与运行巡视来提高运行质量,进而保障系统安全性和可靠性。方法采用紫外光老化、中性盐雾等环境试验对现场维护后隔离/接地开关传动轴原件以及与现场隔离/接地开关传动轴相同修复工艺制作的涂层样板进行环境耐久性测试,并对涂层性能进行评级,对后续维护提出相应建议措施。结果紫外1000h后,传动轴原件表面涂层无明显缺陷,光泽保持率平均值为96.8%、色差ΔE*ab的平均值为0.62,色牢度为4~5级。盐雾1000 h后,传动轴原件表面涂层出现起泡,未出现生锈、开裂、剥落现象,起泡等级为2(S2)、生锈等级为Ri0、开裂等级为0(S0)、剥落等级为0(S0)。结论必须对变电站隔离/接地开关传动轴表面维护涂层予以足够重视。加强工艺质量管理,及时可靠地掌握设备运行状况,故障尽快查明原因排除隐患,提高系统安全性和可靠性。  相似文献   
79.
随着电子废弃物数量的日益增加和对电子废弃物资源化利用要求的提高,电子废弃物经历了由堆存到资源化利用的发展过程.目前电子废弃物资源化技术主要包括物理处理法、化学处理法和热处理法等方法,实现电子废弃物的资源化.  相似文献   
80.
电导率温度校正计算方法的改进   总被引:2,自引:0,他引:2  
通过实验,用分段函数较精确的表示出温度校正系数与温度的关系,对现行电导率温度校正公式进行了改进,可以简化测量过程,提高计算精度。  相似文献   
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