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971.
Air pollution has been associated with daily mortality in numerous studies over the past decade. However most of these studies were conducted in the United States and Europe with relatively few done in Asia. In the current study, the association between ambient air pollution and daily mortality in Taipei, Taiwan's largest city which has a subtropical climate was undertaken, for the period 1994-1998 using a case-crossover analysis. This design is an alternative to Poisson time series regression for studying the short-term adverse health effects of air pollution. The air pollutants examined included particulate matter (PM(10)), sulfur dioxide (SO(2)), ozone (O(3)), nitrogen dioxide (NO(2)), and carbon monoxide (CO). The largest observed effect, which was without statistical significance, was seen for NO(2) and CO levels on deaths due to respiratory diseases (ORs=1.013 and 1.014, respectively). The well established link between air pollution levels and daily mortality may not be as strong in cities in subtropical areas, although other factors such as differences in pollutant mix or the underlying health of the population may explain the lack of a strong association in this study. Further studies of this type in cities with varying climates and cultures are needed.  相似文献   
972.
Environmental Science and Pollution Research - Copious amounts of cucumber vine (CV) derived from crop growing and harvesting are casually discarded in the field, posing severely negative impacts...  相似文献   
973.
A series of hierarchical macro-/mesoporous silica supports (MMSs) were successfully synthesized using dual-templating technique employing polystyrene (PS) spheres and the Pluronic P123 surfactant. Pd was next loaded on the hierarchical silica supports via colloids precipitation method. Physicochemical properties of the synthesized samples were characterized by various techniques and all catalysts were tested for the total oxidation of o-xylene. Among them, the Pd/MMS-b catalyst with tetraethoxysilane/polystyrene weight ratio of 1.0 exhibited superior catalytic activity, and under a higher gas hourly space velocity (GHSV) of 70000 h–1, the 90% conversion of o-xylene has been obtained at around 200°C. The BET and SEM results indicated that Pd/MMSb catalyst possesses high surface area and large pore volume, and well-ordered, interconnected macropores and 2D hexagonally mesopores hybrid network. This novel ordered hierarchical porous structure was highly beneficial to the dispersion of active sites Pd nanoparticles with less aggregation, and facilitates diffusion of reactants and products. Furthermore, the Pd/MMS-b catalyst possessed good stability and durability.  相似文献   
974.
Dedicated, skilled and relatively cheap manpower coupled with efficient manufacturing techniques has elevated China’s status as the world’s factory. China is now capable of producing virtually any product, from cheap toys to some of the most sophisticated goods and equipment. The resultant economic benefits and associated enormous consumption due to rise in per capita income are accompanied by an equally unprecedented negative environmental impact arising from the huge increase of end-of-life (EoL) products. This study aims to understand and prioritise EoL product reverse logistics (RL) factors from Chinese manufacturing sector perspective. Multiple case studies in five different industries within the manufacturing sector have been carried out and analytic hierarchy process (AHP) has been employed to prioritise the governing factors for the successful RL implementation in the Chinese manufacturing sector. Results indicate that Chinese firms are unlikely to embark on RL operations without external factors such as strict government legislation.  相似文献   
975.
Environmental Geochemistry and Health - In this study, soil washing is applied for the remediation of heavy-metal (Pb, Cu and Zn) contaminated paddy soil located near an abandoned mine area. FeCl3...  相似文献   
976.
• China’s rural industrial land (RIL) area quadrupled from 1990 to 2015. • RIL expansion cost 9% of China’s crop production and threatened human/ecosystem safety. • The underprivileged population bears a disproportionally large share of the risks. China’s rural industrialization has been a major driver for its rapid economic growth during the recent decades, but its myriad environmental risks are yet to be fully understood. Based on a comprehensive national land-use data set, our study shows that the area of China’s rural industrial land (RIL) quadrupled during 1990–2015, reaching 39000 km2 in 2015, comparable to urbanization in magnitude but with a much greater degree of landscape fragmentation which implies stronger ecological and environmental impacts. About 91% of the protected areas in the central China were within 50 km from rural industrial land, thus exposed to industrial disturbances. Accelerated rural industrial land expansion, particularly in regions under high geo-hazard risks, led to dramatically increased environmental risks, threatening the safety and health of both rural industrial workers and residents. Moreover, negative effects from rural industrial land expansion could partially offset the crop production growth in recent decades. The underprivileged rural population in the west bears a disproportionally large share of the increased environmental risks. China urgently needs to design and implement sustainable policies to restrict and reshape its rural industrialization. This study aims to inspire policy makers and researchers to rethink the current model of industrial expansion and improve rural industrial land planning, which is important for achieving the sustainable development goals of China.  相似文献   
977.
农药生产建设项目环境影响评价的探讨   总被引:1,自引:0,他引:1  
分析了农药生产建设项目环境影响评价中存在的诸多问题。结合实际工作经验,就农药生产建设项目中的产业政策评价、环境影响的识别、环境风险评价、清洁生产评价和环保治理措施的确定进行了探讨。  相似文献   
978.
常天海  尹俊勋  汪志成  黎曦 《安全》2006,27(6):20-22
介绍了静电放电电磁辐射场的理论模型;针对长导体模型分析了其数学模型的建立方法;讨论了长导体模型实验仿真方法与结果.  相似文献   
979.
In the low-pressure chemical vapor deposition (LPCVD) process, there are many factors that could affect the thin film thickness and homogeneity in the thin film deposition process. Besides temperature, the volume flow rate of the reactant gas, the Mole fraction, and pressure are all affecting factors. On the basis of the forecast mode result of the thermal model of wafer temperature distribution in the previously published article, this study used the optimal method to calculate the conversion rate of the surface of each wafer under simulated conditions of various furnace temperatures and Mole fractions, as well as silane flow rates and pressures, and finally calculated the thin film growth rate and homogeneity of the surface of each wafer.This study validated four types of process conditions, and found that the results were very close to the experimental values in the previous studies, when conditions such as temperature, Mole fraction of silane, flow rate and pressure in the process were changed. This study thus concluded that the proposed process film thickness mode could meet the requirement of the process capacity. This study found that adjusting the heating zone temperature to regulate the film thickness growth rate was able to control uniformity of the film thickness. These feasible adjustment measures could be very effective on the industry commercial processes.Furthermore, the film thickness mode established in this study was used to discuss the application level of the inherently safer design strategies. This study mode could be used to adjust the temperature, mole fraction (mf), flow rate (F) and pressure (P) in the process for a single machine. Under the condition of meeting the film thickness process recipes required by the process, the silane flow rate was lowered through the adjustment of the control system. The study took the silane supply system as the basis of the case study. Based on a daily required silane consumption of 64.4 L, the daily required amount was 1.5 cylinders in the case of using 40 L high-pressure cylinders. The total daily required amount would be three 40 L high-pressure cylinders, including one more reserve amount on top of the daily required amount, which could match the inherently safer design philosophy and the principles of intensification, attenuation and limitation of effects.In terms of the factory evaluation, among all of the 12-inch furnace machines in Taiwanese wafer factories, nine out of 47 sets use silane, and the total daily consumption reaches 579.6 L. The total required amount, including the reserve, is 27 cylinders for 40 L high-pressure cylinders. As for the setting of the gas cabinet, the required amount could be reduced, since the gas supply pipeline could be designed in a multiple circuit. The minimum reactant gas input amount could be obtained in combination with the proposed film thickness mode, and the safety could be improved greatly, in accordance with the inherently safer design philosophy and the principles of intensification, attenuation and limitation of effects. In addition to the process capacity, this study also took the elevation of the inherently safer level into consideration, which could be provided to the industry for more comprehensive design consideration.  相似文献   
980.
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