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691.
Song M Xu Y Jiang Q Lam PK O'Toole DK Giesy JP Jiang G 《Environment international》2006,32(5):676-681
Sediments from two rivers in China, the Haihe and Dagu Rivers, were examined for estrogenic activity using an estrogen receptor (ER)-mediated in vitro bioassay system. ER-active compounds were isolated from sediments by Soxhlet extraction, and the crude extracts were fractionated using a florisil column into three fractions. The estrogenic activity of each extract was detected by measuring luciferase activity in the human breast cancer cell line MCF-7 transfected with a luciferase receptor gene. Significant estrogenic activity was observed in each total extract. The 17beta-estradiol equivalents (E2-EQs) ranged from 8.24 to 95.28 ng E2 g(-1) dw. As a result, the relative estrogenic potencies of three fractions in this study descended in the order of Fraction 3>Fraction 2>Fraction 1. The results of the bioassay analysis indicated the heavy pollution status of these sites with estrogenic contaminants. In this study, five selected chemicals, the natural estrogens 17beta-estradiol (E2) and estrone (E1), and the xeno-estrogens 4-octylphenol (OP), 4-nonylphenol (NP), and Bisphenol A (BPA) were also analyzed using the in vitro bioassay. The estrogenic activity of these chemicals were E2>E1>NP>OP>BPA. 相似文献
692.
宋晓荣 《安全.健康和环境》2010,10(1):25-26
HSE培训是提高员THSE意识,确保安全生产稳定局面的有效途径。河南油田井下作业队伍专业化整合以来,通过制定切实可行的培训计划、合理划分培训层次,采用灵活的培训方式和持续严密的考核,使全员的HSE培训收到了预期的效果。本文结合工作实际,对如何提高全员HSE培训质量进行探讨。 相似文献
693.
Young-Doo Wang Jae-Shuck Song John Byrne Sun-Jin Yun 《Journal of the American Water Resources Association》1999,35(5):1269-1276
This study systematically evaluates residential consumer responses to a utility conservation initiative based on an econometric analysis of a sample of 510 households served by Artesian Water Company, Inc. (New Castle County of Delaware). Using a panel study approach covering the period from 1992 to 1997, this study shows that Artesian's water conservation program has had statistically significant and persistent impacts on residential water consumption. 相似文献
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切实加强我国环境教育师资队伍建设 总被引:4,自引:0,他引:4
新的世纪已经到来,实现中国教育的全面振兴,要求环境教育必须取得实质性进展,这也是我国经济、社会实现可持续发展的必要准备,环境教育师资队伍建设是推动环境教育深入开展的关键,能否稳定、扎实、有效地开展环境教育,取决于有没有一支高素质的从事环境教育的师资队伍,因为,环境教育师资队伍是顺利实现环境教育目的,目标的前提,是组织开展实践性环境教育活动的保障,因此,加强环境教育师资队伍建设意义重大。 相似文献
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Regional vegetation pattem dynamics has a great im- pact on ecosystem and climate change.Remote sensing data and geographical information system (GIS) analysis were widely used in the detection of vegetation pattern dynamics.In this study,the Yellow River Delta was selected as the study area.By using 1986, 1993,1996,1999 and 2005 remote sensing data as basic informa- tion resource,with the support of GIS,a wetland vegetation spa- tial information dataset was built up.Through selecting the land- scape met... 相似文献
700.
Regional vegetation pattern dynamics has a great impact on ecosystem and climate change. Remote sensing data and geographical information system (GIS) analysis were widely used in the detection of vegetation pattern dynamics. In this study, the Yellow River Delta was selected as the study area. By using 1986, 1993, 1996, 1999 and 2005 remote sensing data as basic information resource, with the support of GIS, a wetland vegetation spatial information dataset was built up. Through selecting the landscape metrics such as class area (CA), class percent of landscape (PL), number of patch (NP), largest patch index (LPI) and mean patch size (MPS) etc., the dynamics of vcgetation pattern was analyzed. The result showed that the change of vegetation pattern is significant from 1986 to 2005. From 1986-1999, the area of the vegetation, the percent of vegetation, LPI and MPS decreased, the NP increased, the vegetation pattern tends to be fragmental. The decrease in vegetation area may well be explained by the fact of the nature environment evolution (Climate change and decrease in Yellow River runoff) and the increase in the population in the Yellow River Delta. However, from 1999 2005, the area of the vegetation, the percent of vegetation, LPI and MPS increased, while the NP decreased. This trend of restoration may be due to the implementation of water resources regulation for the Yellow River Delta since 1999. 相似文献