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431.
432.
Cleaner production has long been viewed as an environmental management tool in China and many other countries. This understanding in recent years has become a major barrier that prevents CP from playing its full functions. This article introduces the approach, results and result dissemination of a project set up by the central government of China aiming at controlling the serious pollution of the electrolytic manganese metal industry. Based on experience of this project and our practical experiences of CP audits in more than 200 companies we propose a new model for CP promotion. A preliminary definition of the new model is presented.  相似文献   
433.
Macroinvertebrates are important components of stream ecosystems, and are often used as indicator species for the assessment of river ecology. Numerous studies have shown that substrate is the primary physical environmental variable affecting the taxa richness and density of macroinvertebrates. The aim of this work is to study the effects of the characteristics of streambed substrate, such as grain size, shape, and roughness, on the composition and biodiversity of macroinvertebrates. A field experiment was done on the Juma River, a second-order mountain stream in northern China. Substrata of cobbles, hewn stones, pebbles, coarse sand, and fine sand were used to replace the original gravel and sand bed in a stretch of 30 m in length. The sampling results indicated that the macroinvertebrate assemblage is significantly affected by the grain size, porosity and interstitial dimension of the substrate, while it is rarely affected by the shape and the surface roughness of the experimental substrata. Macroinvertebrate compositions in cobbles and hewn stones were stable and changed least over time. The taxa richness and density of individuals in the substrata of cobbles, hewn stones, and pebbles are much higher than in those of the coarse sand and fine sand.  相似文献   
434.
Associated with the rapid development of the information and electronic industry, liquid crystal displays (LCDs) have been increasingly sold as displays. However, during the discarding at their end-of-life stage, significant environmental hazards, impacts on health and a loss of resources may occur, if the scraps are not managed in an appropriate way. In order to improve the efficiency of the recovery of valuable materials from waste LCDs panel in an environmentally sound manner, this study presents a combined recycling technology process on the basis of manual dismantling and chemical treatment of LCDs. Three key processes of this technology have been studied, including the separation of LCD polarizing film by thermal shock method the removal of liquid crystals between the glass substrates by the ultrasonic cleaning, and the recovery of indium metal from glass by dissolution. The results show that valuable materials (e.g. indium) and harmful substances (e.g. liquid crystals) could be efficiently recovered or separated through above-mentioned combined technology. The optimal conditions are: (1) the peak temperature of thermal shock to separate polarizing film, ranges from 230 to 240 °C, where pyrolysis could be avoided; (2) the ultrasonic-assisted cleaning was most efficient at a frequency of 40 KHz (P = 40 W) and the exposure of the substrate to industrial detergents for 10 min; and (3) indium separation from glass in a mix of concentrated hydrochloric acid at 38% and nitric acid at 69% (HCl:HNO3:H2O = 45:5:50, volume ratio). The indium separation process was conducted with an exposure time of 30 min at a constant temperature of 60 °C.  相似文献   
435.
赵晓东  段鸿业 《安全》2010,31(11):22-25
石油化工科研的试验研究、中试生产场所、试验原料及产品储存等存在着潜在的着火爆炸、中毒、机械伤害、触电等事故。我国"安全第一,预防为主,综合治理"的安全生产方针,其中要把"预防为主"贯穿于安全管理的始终,就是要采取切实有效的措施,事先对可能发生的事故进行预防和控制。  相似文献   
436.
本文介绍了应用彩红外航片,黑白航片分析呼和浩特市城市居民区、工业区、商业贸易区布局结构的技术。  相似文献   
437.
百年工业文明发展范式对自然环境的持续作用,使人类面临环境与发展的双重危机。生态文明具有内在统一性,环境法制是生态文明的应有之义。环境基本法是环境法制的基石,目的条款是环境基本法的元点。旧的目的条款沿袭工业文明发展范式,将发展经济奉为圭臬,始终无法调和人与自然的内在矛盾。修改环境基本法目的条款,融入生态文明因子具有自内而外、自外而内、自上而下以及自下而上四个方面的动力因素。  相似文献   
438.
Four models for human exposure to air pollution are discussed and compared. The simple microenvironment monitoring model measures pollutant concentrations at fixed locations, regarded as proxies for similar locations or microenvironments. Since this model does not require pollutant measurements on the individual level, it is easy to implement. However, the model can only be used to estimate the average exposure in a population, and it does not provide any estimate of the variability and distribution of individual exposures. The replicated microenvironment monitoring model provides some estimates of the variability and distribution. However, because of the possible discrepancy between the microenvironment concentration distribution and the individual concentration distribution, some adjustment might be necessary. Integrated personal monitoring allows direct estimation of the average exposure as well as the variability and distribution of individual exposures. Coupled with the appropriate time budget data, a regression analysis can be applied to estimate the contribution from each microenvironment type. However, possible collinearity problems might result in low precision in those estimates. Moreover, it might be difficult to adjust for a possible Hawthorne effect. Continuous personal monitoring has the advantage of recording exposure in each microenvironment type separately, allowing direct estimation of the average exposure as well as the variability and distribution of exposures in each microenvironment type. Moreover, it can also be conducted in conjunction with a two-stage sampling scheme, using information from a large data base on activity patterns, thereby making more efficient use of the monitoring data. It is also easier to adjust for a possible Hawthorne effect in this design.  相似文献   
439.
浙江省金衢盆地的食用笋资源丰富,开发潜力大,发展食用笋资源是该地区农村致富的重要途径之一。本文在分析该地区食用笋现状的基础上,提出了开发利用对策。  相似文献   
440.
开发楠溪江风景区旅游资源   总被引:1,自引:1,他引:0  
本文分析了楠溪江风景区旅游资源的主要特征,并针对目前旅游资源开发存在的问题,提出了开发楠溪江风景区旅游资源的对策与措施.  相似文献   
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