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961.
This paper presents an experimental study on employing a pellet form of catalyst in photo-reduction of carbon dioxide with water. Water was first absorbed into titania pellets. Highly purified carbon dioxide gas was then discharged into a reactor containing the wet pellets, which were then illuminated continuously for 65 hours using UVC lamps. Analysing the products accumulated in the reactor confirmed that methane and hydrogen were produced through photo-reduction of carbon dioxide with water. No other hydrocarbons were detected. Increasing the temperature in the reactor has showed little change on the amount of methane produced.  相似文献   
962.
从安全生产意识和安全文化的角度,阐述了工地建筑安全管理的意义和方法,提出了建立安全管理体系的必要性。  相似文献   
963.
本文结合鞍钢多年安全生产工作实践,从企业领导者的角度,阐述了安全生产在企业中的地位、作用及重要性,提出了一把手安全生产负责制的对策及实施方法,这对于提高企业领导者的安全素质,搞好企业的安全生产工作具有重要的指导作用。  相似文献   
964.
ABSTRACT: Efforts by state and federal agencies to develop standards and guidelines for protecting and enhancing water quality on grazing lands have led to suggestions that grazed stubble height criteria could be used to determine when cattle should be removed from a specific pasture or grazing area. Until recently only indirect scientific evidence from agronomy and laboratory studies gave support to the stubble height concept. Consequently, a grazing study was initiated on a Montana ranch in 1997 to determine the reduction in overland sediment achieved by grazing a pasture to a predetermined stubble height. Treatments consisted of 7 cm (3 in) grazed, 7 cm (3 in) clipped or mowed, 15 cm (6 in) grazed; 15 cm (6 in) clipped and untreated or natural forage plant height. The five treatments were used in a two‐year trial spanning 1997 to 1999. At the conclusion of this study the magnitude of sediment production was related to the number of intense rain events during the March through June period rather than total precipitation. There was a significant year effect in terms of sediment accumulation (P < 0.01) but no year by treatment effect (P = 0.11). Even though a significant difference in sediment accumulation was detected between the shorter and taller stubble heights (P = 0.04) in both 1998 and 1999, the difference could not be explained by grazed stubble height alone. Close grazing (7 cm stubble) consistently ranked lowest in sediment production (P < 0.01) among all treatments, including the ungrazed control. These results suggest that changes in plant community structure and microtopographic caused by grazing influence sediment entrapment (retention) on hillslopes more than those caused by plant height.  相似文献   
965.
在环境案件调查处理过程中,证据具有重要作用.收集、制作有效的执法证据是环保部门作出具体行政行为的基础.只有掌握充分确凿的证据,才能保证正确认定案件事实,也才能正确适用法律,避免出现行政复议变更或行政诉讼败论情况的发生.在此,根据环境案件的执法的特征和特点阐述了收集、制作证据的方法和要求.  相似文献   
966.
从综合预防的角度出发,探讨环境保护的战略决策清洁生产的内涵,清洁生产审计以及建立清洁生产实施机制。  相似文献   
967.
石化企业是噪声大户,由压缩机、鼓风机、机泵等声源设备及其它背景噪声构成了各种各样的噪声源,不但单源声级峰值高,而且面源辐射面积广,治理难度非常大,辽化公司采取自难而易的原则,对纤维生产中重点噪声源进行了治理,收到了明显的成效。  相似文献   
968.
Organic waste products, potentially harmful to the human health and the environment, are primarily produced in the synthesis stage of manufacturing processes. Many such synthetic unit processes, such as halogenation, oxidation, alkylation, nitration, and sulfonation are common to a large number of organic chemical manufacture in several different industry sectors. The environmental impact of organic chemical syntheses can be significantly reduced by incorporating cleaner unit processes. A review of research and development activities shows that progress is already being made along these lines worldwide, and commercialization of cleaner organic technologies is also proceeding.  相似文献   
969.
环境影响评价中清洁生产分析存在的问题及改进建议   总被引:3,自引:0,他引:3  
论述了清洁生产分析已成为建设项目环境影响评价的重要内容,但尚存在三个主要问题,提出做好清洁生产分析的建议。  相似文献   
970.
S.C. Ray 《Resources Policy》1984,10(2):125-133
The availability of mineral resources plays an important role in India's national economy. Copper, one of the important non-ferrous metals, has various industrial uses and demand for it is increasing in India where the inventory and production of copper, though not comparable with developed countries, shows an impressive growth rate, particularly during the last decade. With an increasing rate of industrial production envisaged in future plans copper consumption is expected to rise. Logistic curves have been used to study the potential long-term production capability under the dynamic concept of reserves and resources, with curves drawn for various estimates of total available resources. The production figures shown are not final and are subject to change due to a number of factors. This approach merely provides a method for projecting trends in future production.  相似文献   
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