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391.
This article discusses the various phases in petroleum product consumption in India from 1960 to 1996, and analyses the changes in consumption patterns. Consumption is growing rapidly although the intensity of petroleum use and the proportion of petroleum in the overall secondary energy consumption is actually on the decline, especially since the mid-1980s. The proportion of middle distillates in total consumption, especially HSD (High Speed Diesel) which accounts for 45%, is very high mainly because of distortions caused by Government subsidies. The article also analyses expected demand for petroleum products up till the year 2010, emphasizing the need to address the particularly fast growing demand for middle distillates. Further, the article discusses various policy issues pertaining to upstream and downstream activities of oil and gas supply, and emphasizes the need for increased investment in exploration and development, better management of existing reserves, rationalization of pricing policies and the creation of modern infrastructure to meet growing needs.  相似文献   
392.
393.
394.
HSE项目管理体系中环境保护专业的作用   总被引:1,自引:0,他引:1  
在对比国内建设项目环保管理体系和HSE环保管理体系的基础上,总结了PMC项目环保管理工作的经验,对HSE项目管理运作模式中环保专业的职能和作用进行了一定程度的探讨。  相似文献   
395.
Rapid detection of aneuploidy using chromosome-specific repetitive DNA probes and the potential diagnostic accuracy of fluorescence in situ hybridization (FISH) on interphase cells of chorionic villus samples (CVS) are presented. Analyses demonstrated the ability to correctly identify aneuploidy using FISH in uncultured CVS. Our preliminary investigation suggests that this technique offers a significant clinical potential to circumvent problems of culture, time, and cost in cytogenetic analysis.  相似文献   
396.
针对海化集团自备热电厂1300t/h煤粉炉原有除尘系统存在的问题进行全面的分析,在此基础上结合厂方提出的要求,确定了改造方案,并捏造了改造设计。改造后实际运行情况表明:1#米除尘系统运行良好,除尘效率超出了厂方提供的要求,达到98.5%以上。  相似文献   
397.
张华  肖雪峰 《环境科技》2000,13(4):45-46
概述了我国“白色污染”的现状及其危害。针对目前“白色污染”的严峻态势,作者提出了对其根治应采取的具体措施。  相似文献   
398.
The wastewater discharged from tanneries lack biodegradability due to the presence of recalcitrant compounds at significant concentration. The focal theme of the present investigation was to use chemo-autotrophic activated carbon oxidation(CAACO) reactor, an immobilized cell reactor using chemoautotrophs for the treatment of tannery wastewater. The treatment scheme comprised of anaerobic treatment, sand filtration, and CAACO reactor, which remove COD, BOD, TOC, VFA and sulphides respectively by 86%, 95%, 81%,71% and 100%. Rice bran mesoporous activated carbon prepared indigenously and was used for immobilization of chemoautotrophs. The degradation of xenobiotic compounds by CAACO was confirmed through HPLC and FT-IR techniques.  相似文献   
399.
Mass level of fine particles (PM2.5) in main cities in China has decreased significantly in recent years due to implementation of Chinese Clean Air Action Plan since 2013, however, O3 pollution is getting worse than before, especially in megacities such as in Shanghai. In this work, O3 and PM2.5 were continuously monitored from May 27, 2018 to March 31, 2019. Our data showed that the annual average concentration of PM2.5 and O3 (O3-8 hr, maximum 8-hour moving average of ozone days) was 39.35 ± 35.74 and 86.49 ± 41.65 µg/m3, respectively. The concentrations of PM2.5 showed clear seasonal trends, with higher concentrations in winter (83.36 ± 18.66 µg/m3) and lower concentrations in summer (19.85 ± 7.23 µg/m3), however, the seasonal trends of O3 were different with 103.75 ± 41.77 µg/m3 in summer and 58.59 ± 21.40 µg/m3 in winter. Air mass backward trajectory, analyzing results of potential source contribution function model and concentration weighted trajectory model implied that pollutants from northwestern China contributed significantly to the mass concentration of Shanghai PM2.5, while pollutants from areas of eastern coastal provinces and South China Sea contributed significantly to the mass level of ozone in Shanghai atmosphere. Mass concentration of twenty-one elements in the PM2.5 were investigated, and their relationships with O3 were analyzed. Mass level of ozone had good correlation with that of Ba (r = 0.64, p < 0.05) and V (r = 0.30, p > 0.05), suggesting vehicle emission pollutants contribute to the increasing concentration of ozone in Shanghai atmosphere.  相似文献   
400.
TiO_2 films have received increasing attention for the removal of organic pollutants via photocatalysis. To develop a simple and effective method for improving the photodegradation efficiency of pollutants in surface water, we herein examined the preparation of a P25-TiO_2 composite film on a cement substrate via a sol–gel method. In this case, Rhodamine B(Rh B)was employed as the target organic pollutant. The self-generated TiO_2 film and the P25-TiO_2 composite film were characterized by X-ray diffraction(XRD), N_2 adsorption/desorption measurements, scanning electron microscopy(SEM), transmission electron microscopy(TEM), and diffuse reflectance spectroscopy(DRS). The photodegradation efficiencies of the two films were studied by Rh B removal in water under UV(ultraviolet) irradiation. Over 4 day exposure, the P25-TiO_2 composite film exhibited higher photocatalytic performance than the self-generated TiO_2 film. The photodegradation rate indicated that the efficiency of the P25-TiO_2 composite film was enhanced by the addition of the rutile phase Degussa P25 powder. As such, cooperation between the anatase TiO_2 and rutile P25 nanoparticles was beneficial for separation of the photo-induced electrons and holes. In addition, the influence of P25 doping on the P25-TiO_2 composite films was evaluated. We found that up to a certain saturation point, increased doping enhanced the photodegradation ability of the composite film. Thus, we herein demonstrated that the doping of P25 powders is a simple but effective strategy to prepare a P25-TiO_2 composite film on a cement substrate, and the resulting film exhibits excellent removal efficiency in the degradation of organic pollutants.  相似文献   
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