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821.
Chen KS Wang HK Peng YP Wang WC Chen CH Lai CH 《Journal of the Air & Waste Management Association (1995)》2008,58(10):1318-1327
The sizes and concentrations of 21 atmospheric polycyclic aromatic hydrocarbons (PAHs) were measured at Jhu-Shan (a rural site) and Sin-Gang (a town site) in central Taiwan in October and December 2005. Air samples were collected using semi-volatile sampling trains (PS-1 sampler) over 16 days for rice-straw burning and nonburning periods. These samples were then analyzed using a gas chromatograph with a flame-ionization detector (GC/FID). Particle-size distributions in the particulate phase show a bimode, peaking at 0.32-0.56 microm and 3.2-5.6 microm at the two sites during the nonburning period. During the burning period, peaks also appeared at 0.32-0.56 microm and 3.2-5.6 microm at Jhu-Shan, with the accumulation mode (particle size between 0.1 and 3.2 microm) accounting for approximately 74.1% of total particle mass. The peaks at 0.18-0.32 microm and 1.8-3.2 microm at Shin-Gang had an accumulation mode accounting for approximately 70.1% of total particle mass. The mass median diameter (MMD) of 3.99-4.35 microm in the particulate phase suggested that rice-straw burning generated increased numbers of coarse particles. The concentrations of total PAHs (sum of 21 gases + particles) at the Jhu-Shan site (Sin-Gang site) were 522.9 +/- 111.4 ng/ml (572.0 +/- 91.0 ng/ml) and 330.1 +/- 17.0 ng/ml (or 427.5 +/- 108.0 ng/ml) during burning and nonburning periods, respectively, accounting for a roughly 58% (or 34%) increase in the concentrations of total PAHs due to rice-straw burning. On average, low-weight PAHs (about 87.0%) represent the largest proportion of total PAHs, followed by medium-weight PAHs (7.1%), and high-weight PAHs (5.9%). Combustion-related PAHs during burning periods were 1.54-2.57 times higher than those during nonburning periods. The results of principal component analysis (PCA)/absolute principal component scores (APCS) suggest that the primary pollution sources at the two sites are similar and include vehicle exhaust, coal/wood combustion, incense burning, and incineration emissions. Open burning of rice straw was estimated to contribute approximately 5.0-33.5% to the total atmospheric PAHs at the two sites. 相似文献
822.
研究了压力式接触氧化法的脱氮性能,分析了容积负荷、溶解氧和停留时间等因素对反应器脱氮效果的影响.研究表明,压力式接触氧化法具有明显的同步硝化反硝化现象,当HRT=1.8 h时,DO高达5.4 mg/L,可获得90%以上的反硝化率.当HRT=1.8 h,溶解氧4~5 mg/L,容积负荷为10~12 kg COD/(m3·d)时,氨氮去除率80%左右,总氮去除率达70%~80%. 相似文献
823.
Comparative on Causes and Accumulation of Selenium in the Tree-rings Ambient High-selenium Coal Combustion Area from Yutangba, Hubei, China 总被引:1,自引:0,他引:1
Liu G Zhang Y Qi C Zheng L Chen Y Peng Z 《Environmental monitoring and assessment》2007,133(1-3):99-103
Toxic trace elements emitted during coal combustion are the main sources of air pollution. They are released into the atmosphere
mainly in the forms of fine ash, smoke and flue, and thus adversely affect plant, animal and human health. Selenium is one
of toxic and the most volatile in coal. Large amount of atmospheric emission of selenium, as well as selenium present and
scrubber stockpiles in ash may create serious environmental problems. In the paper, on the basis of investigating the abundance
and distribution of selenium in plant-rings during recent 20 years, the bioaccumulation of selenium is explained that selenium
in plant, which were collected from the village of selenium-rich coal combustion, is much higher than that in plants collected
away from the village of selenium-rich coal combustion. The main origins of selenium are selenium-rich coal combustion and
high-selenium rock weathered. The selenium recycle by food chain and selenium will accumulate and redistribute in environments. 相似文献
824.
Yu FC Chen CY Lin SC Lin YC Wu SY Cheung KW 《Environmental monitoring and assessment》2007,132(1-3):419-428
As the embodiment of human activities, the change of regional industrial structure is an essential driving factor of global
environmental change. Consequently, the research on the change of regional industrial structure and associated effects on
the environment is one of the key issues of researches on sustainable development, human–environment relationship, and regional
response to global environment change. However, compared to the flourish of researches on environmental impact assessment
of industrial departments, few studies have been conducted to assess the environmental impact of regional industrial structure.
In this study, based on a synthetic analysis of environmental disturbances of different industrial departments, the environmental
impact coefficient of industrial department associated with the index of environmental impact of industrial structure was
constructed, so as to make a quantitative assessment of environmental impact of the change of regional industrial structure.
And the results of the case study in Lijiang City, a rural region of China, have showed that there are two obvious changes
of industrial structure in the study area from 1992 to 2003, associated with a continuous decreasing of the index of environmental
impact of industrial structure, which indicated a positive environmental effects of the change of regional industrial structure. 相似文献
825.
资源和环境的存在价值的经济学基础 总被引:5,自引:0,他引:5
资源与环境的存在价值为独立与人们对资源的现期使用的价值。在资源,环境的代际问题中,存在价值会成为重要的决策参数。本文对存在价值的同予以分陈、归纳,并以反映其特点的结构进行表述;其次对存在价值与其它类别的价值尤其是期权价值,准期作出区分。 相似文献
826.
氯酚与富里酸的缔合作用 总被引:1,自引:0,他引:1
本文用超滤膜方法证实氯酚与富里酸之间存在缔合作用,并计算出表观缔合常数在2.7*10^3--121*10^3ml.g^-1范围内。实验结果表明”PH、富里酸含量,氯酚取代氯原子个数都能够影响K值的大小。 相似文献
827.
应用D412螯合树脂治理含镍电镀废水的研究 总被引:1,自引:0,他引:1
本文研究了D412螯合树脂对Ni(Ⅱ)离子静态和动态的吸收性能,并且研究了使用D412树脂除去和回收电镀废水中镍的最佳条件。 相似文献
828.
刘鹏 《中国安全生产科学技术》2008,4(6)
随着经济全球化和世界一体化进程的加快,城市安全生产问题成为各个国家日益关注的新兴社会问题.我国城市安全生产预警系统还不健全,处理和管理危机能力不强,需要进一步完善.通过运用系统学、管理学等理论和方法,依据城市安全生产现状,构建了城市预警系统的总体框架.通过对预警系统关键技术的分析研究,使城市生产安全事故预警处置做到组织科学化、指挥智能化、处理系统化、保障统筹化,增强和保证城市安全生产综合管理能力和抗风险能力. 相似文献
829.
830.