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991.
渤海主要河口污染特征研究   总被引:32,自引:9,他引:23       下载免费PDF全文
于2000年对渤海湾主要河口及海岸带部分区域与环境毒理学相关的污染特征进行了一次探查分析。结果表明,环渤海湾河口区域部分水质和底泥的环境污染程度属中度或严重污染状态。其中,有些采样点个别重金属元素和有机污染物超过有关环境标准的状况较严重,如在海河口、辽河口及黄河口的个别样品中,有害元素铬(Cr)、镉(Cd)、镍(Ni)、汞(Hg)、砷(As)、铅(Pb)等的含量超标数倍以上,总可检出有机物达200余种,污染物可能主要来源于各类生产单位的废水排放。   相似文献   
992.
北京边界层外来污染物输送通道   总被引:51,自引:11,他引:40  
由京、津、冀气候站历史资料及激光雷达资料分析,在稳定天气条件下,北京市外来污染物各类尺度的输入通道流场分为边界层西南气流、东南气流和东风气流风带型,其中对形成北京输送汇风带的统计表明,西南风带汇发生频率占45%,东南风带汇占36%,东风风带汇占19%。输送通道是指空间和时间稳定性风带,是区域尺度、局地尺度的范围内相继出现的欧拉风场,且有多频率发生的特征。按城市间尺度流型可分为城市间东风、西南风、东南风输送通道。具有一定空间尺度和时间尺度的相继性、接续性输送特征,按配置的天气系统可分为大陆高压南部偏东风输送通道系统、海上高压后部东南风输送通道系统、河套倒槽前西南风输送通道系统、东北低槽前部偏南风输送通道系统等。3个风带流经地区恰好位于华北平原3个主要排放源群地区。   相似文献   
993.
综放开采采空区煤炭自燃特征及其控制研究   总被引:1,自引:0,他引:1  
卢平  鲍杰  韩德明  吴超  廖光煊 《火灾科学》2004,13(3):173-179
针对7201综放面煤层易自燃、回采过程中存在工作面过断层、工作面面长加大接面等影响正常回采速度的现实条件,在理论分析和实验研究基础上,确定了高温热源的位置,及时采取了优化配备工作面风量、顶板走向长钻孔压注阻化液、设置隔漏风墙、气雾阻化及煤柱预注阻化液等综合防治煤炭自燃措施,有效抑制了工作面采空区煤炭自燃,实现了易自燃煤层综放安全开采。研究结果对类似条件的综放安全开采有现实指导价值。  相似文献   
994.
Nitrogen-containing organic pollutants (quinoline, pyridine and indole) are widely distributed in coking wastewater, and bioaugmentation with specific microorganisms may enhance the removal of these recalcitrant pollutants. The bioaugmented system (group B) was constructed through inoculation of two aromatics-degrading bacteria, Comamonas sp. Z1 (quinoline degrader) and Acinetobacter sp. JW (indole degrader), into the activated sludge for treatment of quinoline, indole and pyridine, and the non-bioaugmented activated sludge was used as the control (group C). Both groups maintained high efficiencies (> 94%) for removal of nitrogen-containing organic pollutants and chemical oxygen demand (COD) during the long-term operation, and group B was highly effective at the starting period and the operation stage fed with raw wastewater. High-throughput sequencing analysis indicated that nitrogen-containing organic pollutants could shape the microbial community structure, and communities of bioaugmented group B were clearly separated from those of non-bioaugmented group C as observed in non-metric multidimensional scaling (NMDS) plot. Although the inoculants did not remain their dominance in group B, bioaugmentation could induce the formation of effective microbial community, and the indigenous microbes might play the key role in removal of nitrogen-containing organic pollutants, including Dokdonella, Comamonas and Pseudoxanthomonas. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis suggested that bioaugmentation could facilitate the enrichment of functional genes related to xenobiotics biodegradation and metabolism, probably leading to the improved performance in group B. This study indicated that bioaugmentation could promote the removal of nitrogen-containing organic pollutants, which should be an effective strategy for wastewater treatment.  相似文献   
995.
A sulfate-rich flue gas desulfurization scrubber sludge was used as a substitute backfill material in reclamation of an abandoned coal strip mine. The site was surrounded by monitor wells and the material was characterized for leaching behavior using open column experiments. A drain was placed directly beneath the 45 000 ton fill to enable sampling before dilution or attenuation. The column studies indicated that the scrubber sludge would adsorb manganese, iron, aluminium, cobalt, nickel, thallium and zinc contaminants from the water. Changes in pH appear inadequate to explain the removal by precipitation. The groundwater cleaning phenomenon has been confirmed on a field scale by the drain samples. Boron and molybdenum leach from the fly ash was used to fix the scrubber sludge and serve as marker elements enabling calibration of the dispersivity in computer models of the groundwater system at the site. The leachate front appears to be diluted by a factor of 8 : 1 within the first 15 meters. Since boron and molybdenum release are associated only with the first flush, environmental impacts will be minimal. Columns appear to create a time compression effect on the duration of leaching phenomenon. The effect for this site appears to be at least 5 : 1. The columns were effective in predicting which elements would leach or adsorb in the field and in predicting the actual source concentrations. Other shake tests such as the TCLP and the ASTM shake test were found to be less effective at predicting which elements would leach and were not helpful in predicting field concentrations.  相似文献   
996.
本文通过全程序空白试验、平行样试验及加标回收等试验,对大气手工采样的质量保证问题进行了探讨。  相似文献   
997.
我们以活性炭、TenaxGC、聚氨酯泡沫为吸附剂,采用溶剂洗脱、热解吸、回流提取三种脱附方式,以GC/MS为分析手段,对某电缆厂的漆包线涂漆、橡料加工、橡胶硫化、聚氯乙烯挤塑、聚乙烯交联五条生产工艺废气中的有机物进行了测定,共检出180种有机化合物。同时采用科学方法进行了有机物的筛选,提出了27种电线电缆行业废气中优先控制有机污染物名单  相似文献   
998.
Atmospheric change comprises many phenomena, namely climate change, acidic deposition, stratospheric ozone depletion, SMOG, increasing trend of suspended particulate matter, and hazardous air pollutants (HAPs). Among HAPs, a particular group of Persistent Organic Pollutants (POPs), such as some organochlorine pesticides, has shown a variety of toxic effects, altering the biodiversity of many ecosystems. Because of their persistence in the environment, and of their long range transport, the study of the global cycle of POPs is important in understanding how they can affect biodiversity. This can be accomplished by coupling different approaches: toxicity and ecological studies, emission estimates, and the use of global models.  相似文献   
999.
研究使用CaCO3、CaO、Fe2O3、还原铁粉、Na2CO35种金属催化剂对油漆板材进行热解,收集固、液两相产物进行产率计算和检测分析.结果表明,5种催化剂都有效提高了热解固相产物的产率,CaCO3、Na2CO3以及还原铁粉可以增加液相产品产率.钛元素在所有催化热解固相产物含量均较高,可能造成潜在的环境污染.热解液相...  相似文献   
1000.
Although investigation of microplastics (MPs) present in air environment has been intensively carried out, quantification, characteristics, and distribution of MPs released from the waste burning furnace (WBF) has been missing in literature. The aim of this study was to characterize the presence of MPs released from WBFs and analyze their associated health impacts. The examined locations were at two WBFs (nominated as TPS1 and TPS2) in Sidoarjo, Indonesia. MPs were collected using a 9 cm diameter glass beaker for a period of 8 h at two different sampling points, which are 3 and 15 m from each WBF. Several characteristics of MPs in terms of the number of particles, size, shape, color, and polymer type were comprehensively characterized. This study found that the obtained MPs were of fiber type and in the range of 46–77 and 41–59 particles at TPS1 and TPS2, respectively. In general, the polymer types of MPs were, respectively, cellophane and polytetrafluoroethylene at TPS1 and TPS2. Moreover, it was estimated that about 1.9–2.3 MPs can enter the human body via inhalation. This study offers a pilot examination of MPs released from WBF and findings from this study are crucial to provide new knowledge as a basis to carefully regulate the use of WBF particularly that are located closely to local community.  相似文献   
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