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991.
Compared with the extensive research on the relationship between economic growth and environmental quality in developed countries, there is a paucity of an empirical research on studying the relation for developing countries. Based upon the Environmental Kuznets Curve (EKC) theory, this paper develops regression models for investigating the relationship between economic growth and environmental quality in China. The EKC analysis based on six pollution indices is illustrated with a case study in Jiaxing of Zhejiang, China. 相似文献
992.
Yinghui Zeng Kathleen M Trauth Robert L Peyton Shankha K Banerji 《Waste management & research》2005,23(1):62-71
Waste sorts were conducted during each of the four quarters (or seasons) of 1996 at the City of Columbia Sanitary Landfill. A detailed physical sampling protocol was outlined. Weight fractions of 32 waste components were quantified from all geographic areas that contribute to the Columbia Sanitary Landfill using a two-way stratification method, which accounted for variations in geographical regions and seasons. Comparisons of solid waste generated between locations and seasons were conducted at the 80% confidence level. The composition of the entire waste stream was 41% paper, 21% organic, 16% plastic, 6% metal, 3% glass and 13% other waste. Paper was the largest composition and glass was the smallest composition for all geographical regions. The result of this study was also compared with a 1987 Columbia, Missouri study conducted by EIERA (1987), with studies conducted in other states such as Minnesota, Wisconsin, Oregon and with national study conducted by the USEPA (USEPA 530-R-96-001, PB96-152 160. US Environmental Protection Agency, Office of Solid Waste, Washington, DC). The results of studies from other states are different from this study due to different local conditions, different methodologies and a different scope. There was a small (5%) increase in per capita weight from 1987 to 1996. The total per capita weight in the present study was 60% greater than the national per capita weight reported by the USEPA (1996) due to that the USEPA report excluded industrial, construction and certain commercial waste. The total per capita weight agrees with the national per capita weight for municipal waste reported by Tchobanoglous (1993), which included industrial, construction and commercial sources. The geographical and seasonal effects on the waste composition are evaluated and discussed. Statistical analysis indicates that waste characteristics are different among geographical regions and seasons. The potential for waste recovery and reduction is also discussed. 相似文献
993.
995.
996.
Zhang Q Li Z Zeng G Li J Fang Y Yuan Q Wang Y Ye F 《Environmental monitoring and assessment》2009,152(1-4):123-131
In the study, multivariate statistical methods including factor, principal component and cluster analysis were applied to analyze surface water quality data sets obtained from Xiangjiang watershed, and generated during 7 years (1994-2000) monitoring of 12 parameters at 34 different profiles. Hierarchical cluster analysis grouped 34 sampling sites into three clusters, including relatively less polluted (LP), medium polluted (MP) and highly polluted (HP) sites, and based on the similarity of water quality characteristics, the watershed was divided into three zones. Factor analysis/principal component analysis, applied to analyze the data sets of the three different groups obtained from cluster analysis, resulted in four latent factors accounting for 71.62%, 71.77% and 72.01% of the total variance in water quality data sets of LP, MP and HP areas, respectively. The PCs obtained from factor analysis indicate that the parameters for water quality variations are mainly related to dissolve heavy metals. Thus, these methods are believed to be valuable to help water resources managers understand complex nature of water quality issues and determine the priorities to improve water quality. 相似文献
997.
混凝——吸附法处理油墨废水工艺研究 总被引:7,自引:0,他引:7
采用不同无机混凝剂及氧化还原剂对打印机生产中的油墨废水的混凝及脱色效果进行试验比较,确定了实验室工艺条件及各种混凝剂最佳用量及次序。结果表明,该工艺脱色率达100%,CODcr去除率达51%。 相似文献
998.
Concentration and composition of polychlorinated biphenyls (PCBs) in the typical drinking water sources in Jiangsu Province were studied by scene investigation and physical and chemical analyses as well. Total amount of PCBs in some surface water and surface microlayers exceeded the standard (20 ng/l) in the "Environmental Quality Standard of Surface Water". There were less PCBs in suspended substances and bottom mud. It reflected that there was less PCB pollution in drinking water sources in Jiangsu Province for quite a long period. The main kind of PCBs in the typical drinking water sources was dichlorobiphenyl. Monochlorobiphenyl and trichlorobiphenyl ranked next to dichlorobiphenyl. In the study of PCB distribution in drinking water sources, it was found that the concentration of PCBs in surface microlayer was higher than that in deep water. The concentration of PCBs along the Yangtze River bank was more than that in the middle of Yangtze River. PCBs in the typical drinking water sources mostly came from by-products in industrial production. 相似文献
999.
1000.
大气PM_(2.5)中很多金属元素危害人体健康,且具有源示踪性,因此,开展PM_(2.5)中金属在线监测对污染来源分析和大气污染防治有着重要意义.本研究于2017年4—5月使用美国Cooper环境空气多金属在线监测仪对深圳城市大气PM_(2.5)中金属元素进行连续观测.与同步离线采样测量的金属数据进行比对表明,10种元素(K、Zn、Cu、Mn、Fe、V、Ni、Ti、Pb、Cr)呈现良好的相关性,因而用于后续分析.观测期间大气PM_(2.5)的平均浓度24.8μg·m~(-3),其中10种金属元素总浓度为0.72μg·m~(-3),占比2.9%.Mn、Fe、Cu、Zn和Ti的浓度日变化显示了日间高、夜间低的特征,表明受到本地人为源的显著影响;而K、Pb、Cr浓度日变化无明显波动,说明受区域传输影响较大;Ni与V日变化趋势一致,主要来源为船舶排放.主成分因子分析结果表明,观测期间PM_(2.5)中金属污染来源主要为交通和扬尘源、工业排放/废物燃烧和船舶污染,方差贡献依次为54.3%、19.8%和8.8%. 相似文献