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904.
河北省钢铁工业主要大气污染物减排潜力分析 总被引:1,自引:0,他引:1
通过对河北省钢铁工业存在问题的分析,得出我省钢铁行业主要大气污染物为二氧化硫和粉尘.结合我省钢铁企业的实际情况,从工程技术、政策管理等方面提出相应治理措施,并对"十一五"期间我省钢铁行业二氧化硫和粉尘减排效益进行预测.预测结果显示:采用所建议的减排措施后,我省钢铁工业二氧化硫减排量对全省"十一五"减排计划的贡献率为81.4%;粉尘可减排60%. 相似文献
905.
在对传统室内设计基本观点阐述与理解的基础上分析其整体性、可持续发展,并着重探讨在物质文明和精神文明高度发展的今天,现代室内设计在个性化、自然性、现代性、艺术性等方面发展的新趋势.通过对现代室内设计特点和发展趋势的分析,创造出一个适合人们现代生活的理想空间. 相似文献
906.
固相微萃取(SPME)技术在水质监测中的应用 总被引:3,自引:0,他引:3
固相微萃取技术(SPME)作为一种样品前处理技术,具有方便、快捷、不使用有机溶剂、灵敏度高、价格低廉等优点,已被广泛地应用于环境样品的分析.本文综合评述了采用SPME法预处理环境水体中的有机物、无机离子等污染物的监测情况,并对SPME法在环境水质监测中的应用以及对国外的研究进展进行了展望. 相似文献
907.
Guoyi Zhou Ge Sun Xu Wang Chuanyan Zhou Steven G. McNulty James M. Vose Devendra M. Amatya 《Journal of the American Water Resources Association》2008,44(1):208-221
Abstract: It is critical that evapotranspiration (ET) be quantified accurately so that scientists can evaluate the effects of land management and global change on water availability, streamflow, nutrient and sediment loading, and ecosystem productivity in watersheds. The objective of this study was to derive a new semi‐empirical ET modeled using a dimension analysis method that could be used to estimate forest ET effectively at multiple temporal scales. The model developed describes ET as a function of water availability for evaporation and transpiration, potential ET demand, air humidity, and land surface characteristics. The model was tested with long‐term hydrometeorological data from five research sites with distinct forest hydrology in the United States and China. Averaged simulation error for daily ET was within 0.5 mm/day. The annual ET at each of the five study sites were within 7% of measured values. Results suggest that the model can accurately capture the temporal dynamics of ET in forest ecosystems at daily, monthly, and annual scales. The model is climate‐driven and is sensitive to topography and vegetation characteristics and thus has potential to be used to examine the compounding hydrologic responses to land cover and climate changes at multiple temporal scales. 相似文献
908.
In order to evaluate the municipal sewage treatment systems used at Harbin municipal sewage treatment plant for their pollutant removal efficiency, raw sewage and effluent samples at different treatment stages from the sewage treatment systems were taken, priority pollutants (PPs) were identified and quantified using gas chromatography-mass spectrometry (GC-MS) and inductively coupled plasma-atomic emission spectrograph (ICP-AES). The test results indicated that there were one hundred and fifty species of organic pollutants identified in the raw sewage sample, and only ten species of PPs in all the sewage samples. The levels of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), di-n-octyl phthalate (DnOP) in the sewage samples were 0.779-0.111 microg l(-1), 1.977-0.022 microg l(-1), 6.411-2.194 microg l(-1) and 7.152-2.953microg l(-1), respectively, and most of these phthalate esters (PAEs) were removed through anaerobic/aerobic (A/O) process; The levels of alachlor, acetochlor, atrazine were 0.074-0.021 microg l(-1), 0.160-0.096 microg l(-1) and 0.238-0.184 microg l(-1), respectively, and the total removal efficiency of atrazine was poorest through the sewage treatment systems. The levels of Cu, Cr, Se, Hg, Ni and Zn were 0.0030-0.2327 mg l(-1). It is therefore concluded from these results that the sewage treatment systems were efficient in removing most of the organic and inorganic compounds in this study, and so, the discharged effluent could cause little of the secondary pollution of the aquatic environment. 相似文献
909.
Mineralization of 2,4-dichlorophenol (DCP) was studied by ozone with Mn(2+) as an ozonation catalyst. Laboratory scale semi-batch ozonation experiments were conducted at room temperature. The results showed that trace amount of Mn(2+) accelerated the mineralization of DCP. Total organic carbon removal rate was independent on Mn(2+) dosage at its range of 0.1-0.5 mgL(-1). Dissolved ozone concentration in the solution remained low level in the catalytic ozonation process, which indicated that Mn(2+) catalyzed decomposition of ozone. DCP mineralization was inhibited in catalytic ozonation by the addition of carbonate. Electron spin resonance/spin-trapping technique was used to determine hydroxyl radicals, and the results showed that larger amounts of hydroxyl radicals were produced in catalytic ozonation system than those of single ozonation. Intermediates mainly including aliphatic carboxylic acids were determined qualitatively and semi-quantitatively by GC-MS. And, a general pathway for mineralization of DCP was proposed. 相似文献
910.
Constructed wetlands are considered to be important sources of nitrous oxide (N(2)O). In order to investigate the contribution of nitrification in N(2)O formation, some environmental factors, plant species and ammonia-oxidizing bacteria (AOB) in active layers have been compared. Vegetation cells indicated remarkable effect of seasons and different plant species on N(2)O emission and AOB amount. Nitrous oxide data showed large temporal and spatial fluctuations ranging 0-52.8 mg N(2)O m(-2)d(-1). Higher AOB amount and N(2)O flux rate were observed in the Zizania latifolia cell, reflecting high potential of global warming. Roles of plants as ecosystem engineers are summarized with rhizosphere oxygen release and organic matter transportation to affect nitrogen transformation. The Phragmites australis cell contributed to keeping high T-N removal performance and lower N(2)O emission. The distribution of AOB also supported this result. Statistical analysis showed several environmental parameters affecting the strength of observed greenhouse gases emission, such as water temperature, water level, TOC, plant species and plant cover. 相似文献