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751.
David D. Parrish William C. Kuster Min Shao Yoko Yokouchi Yutaka Kondo Paul D. Goldan Joost A. de Gouw Makoto Koike Tomoko Shirai 《Atmospheric environment (Oxford, England : 1994)》2009,43(40):6435-6441
Ambient measurements of hydrocarbons, carbon monoxide and nitrogen oxides from three mega-cities (Beijing, Mexico City, Tokyo) are compared with similar measurements from US cities in the mid-1980s and the early 2000s. The common hydrocarbon pattern seen in all data sets suggests that emissions associated with gasoline-fueled vehicles dominate in all of these cities. This commonality suggests that it will be efficient and, ultimately, cost effective to proceed with vehicular emission controls in most emerging mega-cities, while proceeding with development of more locally appropriate air quality control strategies through emissions inventory development and ambient air monitoring. Over the three decades covered by the US data sets, the hydrocarbon emissions decreased by a significant factor (something like an order of magnitude), which is greater than suggested by emission inventories, particularly the EDGAR international inventory. The ambient hydrocarbon and CO concentrations reported for the three non-US mega-cities are higher than present US ambient concentrations, but lower than those observed in the 1980s in the US. The one exception to the preceding statement is the high concentrations of CO observed in Beijing, which apparently have a large regional contribution. 相似文献
752.
针对城市生活垃圾焚烧发电的排放问题,以重庆市某垃圾焚烧炉为原始模型,在炉膛两侧炉壁的适当位置设置二次配风口,并采用CFD(计算流体动力学)方法对炉膛内气体的二次燃烧过程进行数值模拟。通过观察对比有无二次配风以及二次配风口位置不同时炉膛内气体的温度场、气体在炉膛内的停留时间分布以及炉膛内气体的混合程度和湍动能等,重点分析了二次风在气体燃烧过程中所起的作用,并对2种不同二次配风口位置时抑制二恶英产生的效果进行了评价。通过对垃圾焚烧炉二次风的优化数值模拟,获得了适合本焚烧炉的比较合理的二次配风条件,可为焚烧炉的设计和改进提供一些有价值的参考。 相似文献
753.
754.
Kim JY Lee BT Shin KH Lee KY Kim KW An KG Park YS Kim JY Kwon YH 《Environmental monitoring and assessment》2007,129(1-3):79-85
Ecological health in a temperate stream impacted by acid mine drainage (AMD) was evaluated by using a multimetric approach
of the Index of Biological Integrity (IBI) based on natural fish assemblage. Recently, this approach has been widely used
in many developed countries as a tool for ecological risk assessments of water environments. We used 10 metric systems, instead
of 12 metrics suggested by Barbour, M. T., Gerritsen, J., Snyder, B. D., & Stribling, J. B. (1999). Rapid Bioassessment Protocols for Use in Streams and Wadeable Rivers: Periphyton, benthic Macroinvertebrates and Fish, 2nd edn. EPA 841-B-99-002. Washington, DC: U.S. Environmental Protection Agency, Office of Water, for a development of the
regional IBI model, and used trophic guilds, habitat guilds, and richness variables for the calculation of IBI values. In
the model, the attributes of four of 11 metrics were modified for the regional application. IBI values in the stream averaged
20.6 (n = 5), indicating a “poor condition” in terms of ecological health according to the modified criteria of U.S. EPA (1993).
Fish Field and Laboratory Methods for Evaluating the Biological Integrity of Surface Waters. EPA 600-R-92-111. Environmental Monitoring systems Laboratory – Cincinnati office of Modeling, Monitoring systems, and quality
assurance Office of Research Development, U.S. EPA, Cincinnati, Ohio, 45268. In particular, mean IBI values in the impacted
areas of sites 2 and 3 were 13, and this health condition was categorized as “very poor condition.” IBI values in the impacted
sites were significantly lower than the values found in the control. Also, we found that fishes in site sites 2 and 3 were
not present during the study, and morphological deformity of Rhynchocypris oxycephalus was observed in site 4, influenced directly by sites 2 and 3, indicating a chemical impact in the sites. From the results
of experiments in which AMD was treated with marine shells at stagnant condition, pH increased up to 6.0 from 3.1, and Fe
and Al were removed up to 99% within 6 h. In the reactor experiment considering field application, pH of effluent maintained
around 7.0. In addition, concentrations of Fe, Al, and heavy metals decreased remarkably in the effluents, and bottom-opened
screen between neutralizer basins showed high effectiveness in the treatment of AMD. 相似文献
755.
The effects of different heavy metals (Cd, Pb), cationic surfactants cetyltrimethylammonium bromide (CTAB), anionic surfactant sodium dodecylbenzenesulfonate (SDBS) and the chemistry of the solution (pH and ionic strength) on the sorption of bisphenol A (BPA) to sediment were studied. Results showed that the presence of Cd and Pb caused a significant increase on the sorption of BPA to sediment and the sorption isotherms were in good agreement with Freundlich equation. The effect of surfactants on the adsorption of BPA onto sediment was found to strongly depend on the type of the surfactants. The presence of CTAB promoted BPA sorption and the amount of BPA adsorbed onto sediment increased linearly with concentration of CTAB. In contrast, the presence of anionic surfactant (SDBS) caused a slight reduction on the sorption of BPA. It was also found that the sorption behavior of BPA was affected by solution pH and ionic strength. The larger amount of BPA was absorbed with higher ionic strength and lower pH. This study may provide important insights into the understanding of the transport and fate of BPA in the environment. 相似文献
756.
Xu T Wang BM Sheng W Li QX Shao XL Li J 《Journal of environmental science and health. Part. B》2007,42(2):173-177
The present study outlines applications of an enzyme-linked immunosorbent assay (ELISA) for the analysis of clenbuterol residues. Antisera were raised from rabbits immunized with diazotized clenbuterol-bovine serum albumin (BSA) conjugate. The assay was specific to clenbuterol with a half-maximum inhibition concentration (IC(50)) of 1.8 ng/mL and 2.5 ng/mL in blank swine urine and phosphate buffer solution, respectively. The assay had high cross-reactivity (86%) with mabuterol, but low with other adrenergic agonists and antagonists. The average recovery of clenbuterol, as measured with the ELISA, ranged from 90% to 112% in swine urine samples and from 86% to 95% in feeds, respectively. This new assay was compared with commercial ELISA test kits. An excellent correlation (r(2) = 0.98) between the two methods and satisfactory recoveries suggest that the new assay can be suitable for the determination of clenbuterol residues in real samples. The assay was used to analyze clenbuterol residues in 103 swine urine samples and 68 feed samples collected from northern China. Approximately 50% of the urine samples and 25% of the feed samples analyzed were found positive (concentration of clenbuterol > or = 1 ppb). The results indicate that clenbuterol was misused in some of the areas surveyed. 相似文献
757.
Preliminary study on the occurrence and distribution of polycyclic musks in a wastewater treatment plant in Guandong, China 总被引:5,自引:0,他引:5
The occurrence and distributions of six polycyclic musks were studied in influent, primary and effluent waters from a municipal wastewater treatment plant (WWTP) in Guangdong. Five polycyclic musk compounds, 1,2,3,5,6,7-hexahydro-1,1,2,3,3-pentamethyl-4H-inden-4-one (DPMI), 4-acetyl-1,1-dimethyl-6-tert-butylindan (ADBI), 6-acetyl-1,1,2,3,3,5-hexamethylindan (AHMI), 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta(g)-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN) were found in wastewater in the WWTP. DPMI, HHCB and AHTN were measured at 0.38-0.69, 11.5-146, 0.89-3.47 microg/l, respectively, in influents. Meanwhile 0.06-0.10 microg/l DPMI, 0.95-2.05 microg/l HHCB, 0.10-0.14 microg/l AHTN were detected in effluents, ADBI and AHMI were also detected in some primary waters and effluents. The results suggested that wastewater from cosmetic plants cause high loadings of polycyclic musks to this WWTP. Under the currently applied treatment technology, the removal efficiencies achieved were 61-75% for DPMI, 86-97% for HHCB and 87-96% for AHTN by transfer to sludge as the main removal route. 相似文献
758.
预浓缩-GC-MS技术研究室内空气中挥发性有毒有机物 总被引:17,自引:0,他引:17
研究了广州市8种典型室内环境中62种挥发性有毒有机物(VOCs)的特征和分布,结果表明:(1)从低至高,家庭、歌舞厅、宾馆、餐厅、图书馆、办公室、大型商业城和停车库室内空气中总挥发性有毒有机物(TVOCs)平均浓度分别为:0.241,0.271,0.471,0.476,0.556,0.910,1.177和2.190mg·m-3;刑室外环境背景参照点白云山平均浓度为0.213mg·m-3,略低于家庭;(2)室内空气污染物具有明显的源特征,根据其VOCs标志化合物和它们的混合比例可以初步判断其来源. 相似文献
759.
Ni-Bin Chang Ho-Wen Chen Shu-Kuang Ning Hsin-Yi Hsu Kwang-Tsao Shao Tsu-Chang Hung 《Environmental Modeling and Assessment》2010,15(5):329-344
Sizing a new reservoir is a challenging task, which normally requires simultaneously a cost-effective, risk-informed, and
forward-looking decision analysis with respect to basin-wide hydrological features, environmental quality, and biological
integrity. Such a sustainable planning approach takes into account the global trend to balance the needs of economic growth,
ecological conservation, and environmental protection. To achieve the goal of sustainability, emphasis in this paper was placed
upon the correlation of three physical, chemical, and biological indices, including the dissolved oxygen (DO), the 5-day biochemical
oxygen demand (BOD5), and the index of biotic integrity (IBI), for the optimal planning of a reservoir in a river basin. This new methodological
paradigm has been employed for sizing an off-stream reservoir in the Hou-Lung River Basin, central Taiwan. The internal linkage
between the water quality parameters (DO and BOD5) and the IBI levels further enables us to formulate a special biotic integrity constraint which reflects fish community attributes
to suit a relatively low-density and unspecialized freshwater fish fauna in response to the changing water quality conditions
in the river basin. The tradeoffs among economic, environmental, and ecological aspects for reservoir sizing can then be based
on the river flow patterns, the water demand, the water quality standards, and the anticipated biological integrity in some
critical river reaches. Findings in a preliminary case study suggest that an optimal pumping scheme may be smoothly maintained
on a yearly basis within a combined multicriteria and multiobjective decision-making process. 相似文献
760.
Jiang-Wen Fan Quan-Qin Shao Ji-Yuan Liu Jun-Bang Wang Warwick Harris Zhuo-Qi Chen Hua-Ping Zhong Xin-Liang Xu Rong-Gao Liu 《Environmental monitoring and assessment》2010,170(1-4):571-584
Inter-annual dynamics of grassland yield of the Three Rivers Headwaters Region of Qinghai–Tibet Plateau of China in 1988–2005 was analyzed using the GLO-PEM model, and the herbage supply function was evaluated. The results indicate that while grassland yield in the region showed marked inter-annual fluctuation there was a trend of increased yield over the 18 years of the study. This increase was especially marked for Alpine Desert and Alpine Steppe and in the west of the region. The inter-annual coefficient of variation of productivity increased from the east to the west of the region and from Marsh, Alpine Meadow, Alpine Steppe, Temperate Steppe to Alpine Desert grasslands. Climate change, particularly increased temperatures in the region during the study period, is suggested to be the main cause of increased grassland yield. However, reduced grazing pressure and changes to the seasonal pattern of grazing could also have influenced the grassland yield trend. These findings indicate the importance of understanding the function of the grassland ecosystems in the region and the effect of climate change on them especially in regard to their use to supply forage for animal production. Reduction of grazing pressure, especially during winter, is indicated to be critical for the restoration and sustainable use of grassland ecosystems in the region. 相似文献