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131.
利用克氏螯虾触角电位监测水体Hg~(2+)污染的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
随着工业的发展,水体污染日趋严重。一定量的重金属对生物体和人体的生理生化功能具有多方面的毒性作用。水环境中高浓度的Hg~(2+)对生物的危害极大,无机汞中又以HgCl_2为最。在水污染生物监测的研究领域内,国外已有用螯虾作为实验动物的报道。然而,迄今尚未见有Hg~(2+)影响淡水螯虾触角感觉功能的报道。  相似文献   
132.
The research was aimed at determining the depth to the watertable, aquifer thickness and subsurface geology of the studyarea thus revealing its groundwater distribution as well as its potential as a substitute to the surface water resources.Vertical electrical soundings were carried out in the study area with maximum electrode spread. The Schlumberger electrode configuration technique was adopted. VES data were processedusing Schlumberger analysis package. Lithologic logs of alreadyexisting boreholes in the study area were collected, evaluatedand comparison were carried out. The results reveal alternatinglayers of sands, sandstones, gravel and clay. The lithologiclogs revealed that the study area is underlain by coastal sands (Benin formation). The water table varies from 10–64 m and thickness of the aquifer ranges from 20–80 m. Results show that the study area is underlain by a thick extensive aquifer that has a transmissivity of 2.8 × 10-2m2 s-1 to 3.3 × 10-1m2 s-1 and storativity 1.44 × 10-4 to 1.68 × 10-3m s-1 values. The specific yield is about 0.31.The sandy component of the study area forms more than 90% ofthe sequence, therefore the permeability, the transmissivity andthe storage coefficient are high with an excellent source of groundwater resources.  相似文献   
133.
介绍了低压电器高原环境适应性技术研发平台建设的主要内容及关键技术,平台的成功建设填补了我国大容量低压电器高原环境模拟试验能力的空白,为高原型低压电器及成套设备的研发提供有效手段。  相似文献   
134.
对大型多功能公共建筑的电气设计中的负荷分级、负荷计算、用电计量与电费计收、低压电气主接线形式等几个方面的问题进行了探讨  相似文献   
135.
The article establishes an evaluation index system of the intensive land use from the perspective of enterprises. It is based on the questionnaire survey and evaluates the levels of the intensive use of the land in the electrical machinery and equipment manufacturing industry in Changzhou, Nantong, and Yancheng of Jiangsu Province. The evaluation result shows that there is obvious difference in the levels of the intensive use of the land in this industry in the three cities. The present article makes a detailed analysis on the causes of the difference. The analysis shows difference in results of the socio-economic and urban development stage, industrial features, population density, and technological progress. Finally, it proposes some suggestions to improve the efficiency of the industrial land use.  相似文献   
136.
This paper presents an overall design method to better consider the energy consumption of electrical and electronic equipment during the use phase. This aspect is often considered as the most important environmental aspect in active electrical and electronic equipment during its life cycle. The proposed method, called ‘Synergico’, characterises the product energy efficiency according to its modes, its functions and its sub-assemblies. It also articulates three tools: one assessment tool, one improvement tool and one environmental check tool. These tools are integrated along a typical product design process. The method therefore helps designing more energy-efficient products without compromising other performances such as ergonomics, functional performances, security, recyclability or costs. The three tools and the overall method are presented. A case study illustrates the way it works and is discussed.  相似文献   
137.
The aim of this research was to define a sequence of actions to guide redesign propositions for electrical and electronic equipment products, which minimise negative consequences to the environment after the end of their useful life. Current practices mainly encourage the examination of individual problems as disassembly process and identification of suitable product end-of-life (EOL) treatment strategies. There also exist previous studies that try to incorporate EOL concerns in product design phase. In most cases, the main problem is the limited available EOL information because of its delayed retrieval. The proposed method focuses primarily on minimising this problem. The steps of the analysis performed include the selection of the optimal EOL treatment strategy and, afterwards, the evaluation of its results concerning the environment. In parallel, product design characteristics are grouped and examined concerning their expected significance for the environment in the EOL stage. The results from the previous stages are combined and product improvement actions are proposed for further examination in the redesign stage. The general framework used to conduct all these actions is lean thinking methodology. In the end, results concerning the application of the proposed method on a distribution transformer are presented.  相似文献   
138.
The study consisted of describing, using a questionnaire, the musculoskeletal symptoms in two industries in the electrical sector. The questionnaire was distributed to more than 600 workers in the two industries. The questionnaire described four types of variables: usual population data (age, gender, experience, etc.), certain work variables, the regions of the body affected in the past 12 months and in the past 7 days, and the severity of the symptoms. Ten variables were used to provide a symptom severity index. In the two plants, the women reported more frequent and more serious problems than the men and the least experienced workers were the most affected. In Plant 1, the questionnaire pinpointed two work sectors, whereas in Plant 2, the problems were found not to be concentrated in a few sectors, but distributed among different jobs throughout the entire plant.  相似文献   
139.
新版标准GB 4706.1《家用和类似用途电器的安全第1部分:通用要求》中,19.11.4对带有电子断开开关、待机等的家用电器产品有新的要求,引用了EMS的标准,测试项目较多,且不合格原因复杂,因此本文详细介绍了此类电器产品的试验及不合格对策,以供试验人员参考。  相似文献   
140.
高尚  高强 《环境技术》2013,(1):24-28
振动试验是汽车产品设计验证和质量检验重要试验方法。本文主要从试验标准、试验条件、振动试验中主要参数的计算推导及应用、试验工装的设计、试验中应注意的问题等方面对电动汽车电机及其控制器的振动试验进行介绍。  相似文献   
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