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91.
在完成国家"863"项目"重点城市群大气复合污染综合防治技术与集成示范"(3c-star)的过程中,我们研发了具有自主知识产权的"区域大气环境综合管理和辅助决策系统",其中创造性地利用NetCDF、Silverlight、WebGIS、粒子系统、多媒体等技术实现了空气污染预测动态可视化数据展示。本文阐述了工作的背景、技术要点及成果。  相似文献   
92.
地下渗滤系统处理农村生活污水的研究   总被引:10,自引:1,他引:9  
在天津武清区一村落构建了2个并行的地下渗滤系统,考察了其对农村生活污水的处理效果。该系统水力负荷为10 cm/d,处理能力为50 t/d。填充介质选用土壤、陶粒、炉渣和两种自然有机质,按5∶2∶2∶1的比例配置的人工土层。结果表明地下渗滤系统对污水中各种主要污染因子均有一定的去除效果,在进水COD和C/N较低的不利条件下,COD、总磷、氨氮、总氮、悬浮物均得到有效去除,出水中各项污染指标平均浓度均达到《城镇污水处理厂污染物排放标准》中的一级A标准;具体到不同的污染指标,添加了不同有机质的2个并行系统的处理效果也有所不同。总体上看,地下渗滤系统作为农村生活污水的处理设施有很好的应用前景。  相似文献   
93.
Heavy metal pollution in road runoff had caused widespread concern since the last century. However, there are little references on metal speciation in multiple environmental media (e.g., rain, road sediments, and road runoff). Our research targeted the investigation of metal speciation in rain, road sediments, and runoff; the analysis of speciation variation and mass balance of metals among rain, road sediments, and runoff; the selection of main factors by principal component analysis (PCA); and the establishment of equation to evaluate the impact of rain and road sediments to metals in road runoff. Sequential extraction procedure contains five steps for the chemical fractionation of metals. Flame atomic absorption spectrometry (Shimadzu, AA-6800) was used to determine metal speciation concentration, as well as the total and dissolved fractions. The dissolved fractions for both Cu and Zn were dominant in rain. The speciation distribution of Zn was different from that of Cu in road sediments, while speciation distribution of Zn is similar to that of Cu in runoff. The bound to carbonates for both Cu and Zn in road sediments were prone to be dissolved by rain. The levels of Cu and Zn in runoff were not obviously influenced by rain, but significantly influenced by road sediments. The masses for both Cu and Zn among rain, road sediments, and road runoff approximately meet the mass balance equation for all rainfall patterns. Five principal factors were selected for metal regression equation based on PCA, including rainfall, average rainfall intensity, antecedent dry periods, total suspended particles, and temperature. The established regression equations could be used to predict the effect of road runoff on receiving environments.  相似文献   
94.
This study is a bibliometric analysis of solid waste research to evaluate the current trends, using the literature in the Science Citation Index (SCI) database from 1993 to 2008. Analyzed aspects included document type, language, and publication output as well as distribution of journals, subject category, countries, institutes, title-words, author keywords, and ‘Keywords Plus’. An evaluating indicator, h-index, was applied to characterize the solid waste publications. The trend of publication outputs during 1993–2008 coincided with a power and an exponential model. Based on the exponential model during 2001–2008, the number of articles on solid waste in 2013 is predicted to be twice that in 2008. The most common subject category is environmental science and the most productive journal is Waste Management. The USA with most publications and China with the highest growth rate were compared. Finally, author keywords, words in title, and ‘Keywords Plus’ were analyzed to provide research emphasis. The results showed that mainstream research was centered on the following methods: recycling, landfilling, composting and waste-to-energy. Heavy metals, fly ash and sewage sludge were considered recent research hotspots.  相似文献   
95.
采用混凝-超滤膜短流程工艺对大伙房水库原水进行处理,考察其除污染性能和膜污染情况,并对该短流程工艺参数进行优化。结果表明,当利用超滤膜直接过滤原水时,膜污染较重,并且对污染物质的去除率较低;而采用混凝-超滤短流程工艺时,膜污染得到一定程度上的缓解;当絮凝剂投加量为7 mg/L、膜清洗周期为30 min时,对浊度、CODMn和UV254的去除率分别为95.61%、40.42%和37.12%,出水水质能够满足生活饮用水卫生标准。  相似文献   
96.
The concentrations, compositional profiles, and possible sources of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF) in water column and surface sediment samples from the lower reaches of the Yangtze River were investigated, and the potential risks posed by these chemicals were evaluated. Concentrations of the 17 2,3,7,8-substituted PCDD/PCDF in the water and sediment samples ranged from 0.45 to 10.0 pg TEQ/L (mean 2.34 pg TEQ/L) and from 0.31 to 51 pg TEQ/g dw (mean 5.25 pg TEQ/g dw), respectively. Water and sediments from the Nanjing–Nantong sections of the Yangtze River were found to have elevated PCDD/PCDF levels, and the PCDD/PCDF TEQ concentrations in 13 sediment samples exceeded the probable effect levels (PEL), above which adverse biological effects are likely. Multivariate statistical analysis indicated that the principal PCDD/PCDF contamination source for the water and sediment was the production and use of pentachlorophenol (PCP) or sodium pentachlorophenate (PCP-Na). PCDD/PCDF concentrations were stable over time near the Yangtze River Estuary but had increased sharply in recent decades in the Nanjing–Nantong section, which will have been related to the growth in industrial activities and other anthropogenic PCDD/PCDF sources. Total organic carbon (TOC) and PCDD/PCDF concentrations correlated significantly (R?=?0.474, P?<?0.01), suggesting that TOC plays an important role in the transport and re-distribution of PCDD/PCDF in the Yangtze River basin.  相似文献   
97.
PRB强化垂直流人工湿地系统处理煤矿废水   总被引:1,自引:0,他引:1  
针对常规人工湿地系统处理高浊含氮磷的有机煤矿废水不佳的问题,采用PRB与人工湿地耦合的方法,进行砂箱模拟实验研究。实验结果表明,由无烟煤、钢渣及沸石构建的PRB强化垂直流人工湿地系统对NH4+-N、PO34--P、Mn2+、COD、SS的去除率分别达到88.84%、96.08%、98.98%、85.78%和94.00%,与常规人工湿地相比,具有处理效率高、水力负荷大、占地面积小等特点,更便于运行管理。  相似文献   
98.
The effectiveness of homologous and heterologous formats in a nanocolloidal gold-based immunoassay for pesticide residue determination was investigated. Parathion, one of the most toxic organophosphorus pesticides, was used as the target analyte. One-step homologous and heterologous test strips based on a nanocolloidal gold-labeled monoclonal antibody were developed for the rapid detection of parathion residues. The results showed that the heterologous format was more effective than the homologous format, being more sensitive, more specific to parathion and more tolerant of matrix interferences. The best competitive hapten was found to have a moderate heterology and the opposite electronic distribution to the immunizing hapten. The detection limits for parathion using the preferred heterologous strip were 1 μg/L in water samples and 5 μg/kg in soil and food samples.  相似文献   
99.
超滤膜深度处理染整废水的膜污染机理   总被引:1,自引:0,他引:1  
付乐乐  李方  吴亮  王歌 《环境工程学报》2013,7(4):1313-1318
实验采用不同规格和材料的超滤膜进行染整二级尾水分离实验,对超滤膜污染机理及影响因素进行了分析。实验采用红外光谱分析了聚醚(PES)膜、聚砜(PSF)膜和聚醚酰亚胺(PEI)膜3种超滤膜材料,对比了污染前后膜面的接触角以及不同切割分子量对膜通量及出水水质的影响,并利用线性化的Herman堵塞模型拟合了不同分子量超滤膜的堵塞模型,初步探讨了超滤膜的污染机理。实验结果表明,膜材料表面亲水性基团的多少与初始膜通量大小成正比,出水COD值随超滤膜切割分子量减小而减小。切割分子量同为2 000 Da的3种超滤膜中,PES膜的处理效果最佳,出水COD平均值为47.81 mg/L;PEI膜通量最高,平衡通量可达50 L/(m2.h);切割分子量为1 000、10 000的超滤膜堵塞机理符合滤饼过滤模型,100 000的超滤膜堵塞机理更接近于完全堵塞模型;1 000的聚醚砜材质膜(PES)更适合此类废水的深度处理。  相似文献   
100.
Evenly distributed sampling design is generally considered as an efficient sampling design. It is widely used in sampling for the environmental survey. In this paper, we present a novel method for generating N evenly distributed samples within a given irregular polygon via simulating the movements of some ideal homogeneous point charges. Initially, charges are randomly put into the sampling region; then, they are freed and held orderly; and after enough runs, the charges will finally reach a stable state with all of them having a zero resultant force and velocity; and so they distribute evenly within the region. Their layout can thus be considered as an evenly distributed sampling design. The main advantages of this method are: (1) it is easy to understand and implement; (2) it is efficient in both running and generating better designs. Analysis and experimental results indicate that this method is an efficient and robust method for generating even sampling designs for 2D polygonal sampling region.  相似文献   
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