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891.
Concentrations of atmospheric PM10 and chemical components (including twenty-one elements, nine ions, organic carbon (OC) and elemental carbon (EC)) were measured at five sites in a heavily industrial region of Shenzhen, China in 2005. Results showed that PM10 concentrations exhibited the highest values at 264 μg/m3 at the site near a harbor with the influence of harbor activities. Sulfur exhibited the highest concentrations (from 2419 to 3995 ng/m3) of all the studied elements, which may be related to the influence of coal used as fuel in this area for industrial plants. This was verified by the high mass percentages of SO42-, which accounted for 34.3%-39.7% of the total ions. NO3-/SO42- ratios varied from 0.64-0.71, which implies coal combustion was predominant compared with vehicle emission. The anion/cation ratios range was close to 0.95, indicating anion deficiency in this region. The harbor site showed the highest OC and EC concentrations, with the influence of emission from vessels. Secondary organic carbon accounted for about 22.6%-38.7% of OC, with the highest percentage occurring at the site adjacent to a coal-fired power plant and wood plant. The mass closure model performed well in this heavily industrial region, with significant correlation obtained between chemically determined and gravimetrically measured PM10 mass. The main constituents of PM10 were found to be organic materials (30.9%-69.5%), followed by secondary inorganic aerosol (7.9%-25.0%), crustal materials (6.7%-13.8%), elemental carbon (3.5%-10.8%), sea salt (2.4%-6.2%) and trace elements (2.0%-4.9%) in this heavily industrialized region. Principal component analysis indicated that the main sources for particulate matter in this industrial region were crustal materials and coal/wood combustion, oil combustion, secondary aerosols, industrial processes and vehicle emission.  相似文献   
892.
The stamp-charging coke making process has some advantages of improving the operation environment, decreasing fugitive emission, higher gas collection efficiency as well as less environmental pollution. This article describes the different structure strength and high temperature thermal properties of 4 different types of coke manufactured using a conventional coking process and the stamp-charging coke making process. The 4 kinds of cokes were prepared from the mixture of five feed coals blended by the petrography blending method. The results showed that the structure strength indices of coke prepared using the stamp-charging coke method increase sharply. In contrast with conventional coking process, the stamp-charging process improved the coke strength after reaction but had little impact on the coke reactivity index.  相似文献   
893.
The microwave radiation oxidation process, Fenton as catalytic agent, was used to remove the thiocyanate from the industrial wastewater. The effects of microwave power, radiation time, pH and the feeding in ways of catalyst on the degradation rate of synthetic wastewater were investigated using the microwave radiation oxidation process by orthogonal experiment. The results show Fenton catalyst ratio was 1:20, the microwave radiation power was 900 W, the microwave radiation time was 7 min and the value of pH was 3. Under the optimum conditions, the removal of KSCN can reach over 90%. The apparent kinetics of removal was studied, which conformed to kinetics first-class reaction. In short, for the thiocyanate from the industrial wastewater, microwave-Fenton oxidation method is feasible and effective.  相似文献   
894.
河流污染主要是指污染物直接或间接地通过地表径流或其他方式进入河流而引起河流自净能力和环境功能下降的现象,主要表现为水体黑臭和富营养化。目前,随着城镇化、工业化进程的加快,人口的急剧增长,导致我国河流污染日益严重。河流污染程度与净流量、产业结构及人口规模密切相关。坚持走可持续发展道路,转变先污染后治理的传统观点,积极落实总量控制制度,彻底解决水环境污染问题。  相似文献   
895.
Tai Lake (Ch: Taihu) has attracted international attention forcyanobacteria blooms. However, the drivers of cultural eutrophication, especially long-term socio-economic indicators have been little researched. The results of research demonstrate how socio-economic development affected quality of water and how it has been improved by anthropogenic activities. This study described variability in indicators of water quality in Tai Lakeand investigated thedrivers. Significant relationships existed between concentrations of annual mean total nitrogen (TN), total phosphorous (TP), chemical oxygen demand (COD) and biological oxygen demand (BOD), and population, per capital gross domestic production (GDP) and sewage discharge (p?<?0.05). However, mechanisms causing change varied among TN, TP, COD and BOD. Before 2000, the main contributors to increases in concentrations of TN were human population, GDP and volumes of domestic sewage discharges. After 2000, discharges of industrial sewage become the primary contributor. After 1998, the regressions of annual mean TN, TP and COD on per capital GDP, population and domestic sewage discharge were reversed compared to the former period. Since 1999, an apparent inverted U-shaped relationship between environmental pollution and economic development has developed, which indicated that actions taken by governments have markedly improved quality of water in Tai Lake. The statistical relationship between BOD and per capital GDP didn’t conform to the Kuznet curve. The U-shaped Kuznet curve may offer hope for the future that with significant environmental investments a high GDP can be reached and maintained without degradation of the environment, especially through appropriate management of industrial sewage discharge.  相似文献   
896.
897.
针对海上油气处理系统在恶劣的作业环境下可靠性低的特点,采用RAM分析技术对某海上石油平台油气处理系统进行可靠性和可用度分析,建立可靠性数学模型,用可靠性分析的算法计算出系统主要设备的可靠性值和系统在寿命周期内可用度变化趋势。应用结果表明:运用RAM分析技术能够计算出寿命周期内油气处理系统的可用度分布规律以及辨识出系统薄弱环节,为提高油气处理系统的可靠性以及改进系统配置等方面提供措施及建议。  相似文献   
898.
随着海绵城市规划建设的陆续开展,低影响开发(LID)的理念也深入人心并得到广泛应用,国内各地均结合自身实际情况提出了年径流总量控制率的目标.事实上,各地在实践中也都逐渐总结出,将年径流总量控制率的目标转化为控制的雨量更容易落地实施,而实现目标的其中一个关键抓手就是雨水调蓄设施.通过对调蓄设施的类型、用途及标准等内容的分析和思考,提出规划建设中应当注意的问题和建议,为海绵城市建设提供一些参考,促进调蓄设施更好的发挥作用.  相似文献   
899.
This study aimed to provide a greater understanding of the systemic factors involved in coal mine accidents and to examine the relationships between the contributing factors across all levels of the system. Ninety-four extraordinarily major coal mine accidents that occurred in China from 1997 to 2011 were analyzed using the human factors analysis and classification system (HFACS). The empirical results showed that the frequencies of unsafe behaviors, inadequate regulation and failure to correct hidden dangers were the highest among five levels, 14 categories and 48 indicators, respectively. The odds ratio technique was applied to quantitatively examine the relationships between contributing factors. Various statistically significant associations were discovered and should receive greater attention in future attempts to develop accident measures. In addition, several strategies concerning the main contributing factors and routes to failure are proposed to prevent accidents from reoccurring in an organization.  相似文献   
900.
本文应用全国排污申报数据 ,按 1 /6°× 1 /6°网格精度估算了 1 995年长江三角洲地区固定燃烧源SO2 、NOx、CO和HC的排放分布。  相似文献   
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