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21.
对使用国产防锈水(主要成分为亚硝酸钠和三乙醇胺)的一个工厂进行肿瘤流行病学调查,发现该厂人员恶性肿瘤发病率略有增加。经长期给大白鼠饮用防锈水实验证明,该法可导致大鼠胰腺腺泡增生和不典型增生并能诱发出对照动物所没有的胰腺癌,同时还可引起胃粘膜的增生和胃乳头状瘤。 相似文献
22.
Li Ning Li Guangming Yao Zhenya Zhao Jianfu 《Frontiers of Environmental Science & Engineering in China》2007,1(2):190-195
Catalytic wet air oxidation (CWAO) is one of the most promising technologies for pollution abatement. Developing catalysts
with high activity and stability is crucial for the application of the CWAO process. The Mn/Ce complex oxide catalysts for
CWAO of high concentration phenol-containing wastewater were prepared by coprecipitation. The catalyst preparation conditions
were optimized by using an orthogonal layout method and single-factor experimental analysis. The Mn/Ce serial catalysts were
characterized by Brunauer-Emmett-Teller (BET) analysis and the metal cation leaching was measured by inductively coupled plasma
torch-atomic emission spectrometry (ICP-AES). The results show that the catalysts have high catalytic activities even at a
low temperature (80°C) and low oxygen partial pressure (0.5 MPa) in a batch reactor. The metallic ion leaching is comparatively
low (Mn<6.577 mg/L and Ce<0.6910 mg/L, respectively) in the CWAO process. The phenol, CODCr, and TOC removal efficiencies in the solution exceed 98.5% using the optimal catalyst (named CSP). The new catalyst would
have a promising application in CWAO treatment of high concentration organic wastewater.
Translated from Techniques and Equipment for Environmental Pollution Control, 2005, 6(2): 40–44 [译自: 环境污染治理技术与设备] 相似文献
23.
环境执法,是国家行政执法的重要组成部分,也是我国环境法制建设的一个重要组成部分。从我国环境行政执法的现状出发,分析和剖析了环境执法中存在的问题及原因,并结合目前环境执法工作实际,提出切实可行的对策建议。 相似文献
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区域环境质量综合评价的一种方法——Fuzzy概率法 总被引:7,自引:1,他引:7
本文应用Fuzzy概率原理,在对区域环境内各单项污染指标进行分级评价的基础上,考虑各单项污染指标在总体中的权重,并综合各单项污染指标的作用,给出区域环境内环境“总”质量的综合评价。 相似文献
26.
本报告介绍DDT经金属对处理后降解产物的分析鉴定和有关反应机制的初步研究。 降解产物主要是用气相色谱—质谱联用分析鉴定的。水溶液中的DDT用Cu-Zn金属对还原其降解产物经鉴定是DDD、DDMS、DDE_t,它们是DDT分子脱去烷基碳原子上不同数目的氯原子的产物。而在Cu-Fe金属对作用下,水溶液中的DDT的还原则是同时得到四种不同类型的产物。它们是DDT脱去烷基碳原子上的1个和3个氯原子的DDD和DDE_t;DDT脱氯、氧化产物DBP和DBH;DDT脱去HCI生成的DDE;两个DDT分子二聚脱氯的产物TTTB和TTDB。 实验证明金属对对DDT的作用是催化还原反应,金属对起着催化剂和还原剂双重作用。通过实验结果对DDT在金属对作用下的反应机制进行了初步探讨。 相似文献
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Land use as a mitigation strategy for the water-quality impacts of global warming: a scenario analysis on two watersheds in the Ohio River Basin 总被引:4,自引:0,他引:4
This study uses an integrative approach to study the water-quality impacts of future global climate and land-use changes. In this study, changing land-use types was used as a mitigation strategy to reduce the adverse impacts of global climate change on water resources. The climate scenarios were based on projections made by the Intergovernmental Panel on Climate Change (IPCC) and the United Kingdom Hadley Centre's climate model (HadCM2). The Thornthwaite water-balance model was coupled with a land-use model (L-THIA) to investigate the hydrologic effects of future climate and land-use changes in the Ohio River Basin. The land-use model is based on the Soil Conservation Service's curve-number method. It uses the curve number, an index of land use and soil type, to calculate runoff volume and depth. The ArcView programming language, Avenue, was used to integrate the two models into a geographic information system (GIS). An output of the water-balance model, daily precipitation values adjusted for potential evapotranspiration, served as one of the inputs into the land-use model. Two watersheds were used in the present study: one containing the city of Cincinnati on the main stem of the Ohio River, and one containing the city of Columbus on a tributary of the Ohio River. These cities represent two major metropolitan areas in the Ohio River Basin with different land uses experiencing different rates of population growth. The projected hypothetical land-use changes were based on linear extrapolations of current population data. Results of the analyses indicate that conversion from agricultural land use to low-density residential land use may decrease the amount of surface runoff. The land-use practices which generate the least amount of runoff are forest, low-density residential, and agriculture; whereas high-density residential and commercial land-use types produce the highest runoff. The hydrologic soil type present was also an important factor in determining the amount of runoff and non-point-source pollution. A runoff-depth matrix and total nitrogen matrix were created for Cincinnati and Columbus to describe possible land-use mitigation measures in response to global climate change. The differences in Cincinnati and Columbus were due to differences in geographic location, air temperature, and total runoff. The results of this study may be useful to planners and policy makers for defining the possible impacts of future global climate and land-use changes on water resources. 相似文献
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