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111.
Shanghai is a cosmopolitan city and one of the most important economic centers in China, but is saddled with serious environmental problems resulting from a recent industrial transformation. This paper examines the interactive relationships between economic growth, eco-efficiency of urban metabolism, and environmental performance of the Shanghai metropolitan area since the 1990s using 15 indicators. This study has revealed an enhanced eco-efficiency of water and energy use as well as an improved overall environmental quality in the central urban districts of Shanghai. Both TGDP (total GDP) and GDP per capita increased rapidly at the annual rate of 16.28% and 15.91%, respectively. In contrast, energy consumed per 10000RMB YUAN GDP (ECG), water consumed per 10000RMB YUAN GDP (WCG), wastewater discharged per 10000RMB YUAN GDP (WWDG), and waste gases emitted per 10000RMB YUAN GDP (WGEG) decreased at the annual rate of 9.34%, 10.69%, 14.57%, and 8.52%, respectively. The rapid decline in ECG, WCG, WWDG, and WGEG indicates an enhanced eco-efficiency of urban metabolism. However, uncontrolled emission of wastes from domestic instead of industrial sources adversely affected the overall environmental quality. In addition, suburban areas have undergone rapid economic growth at the cost of human health deterioration, as measured by mortalities and relative mortality ratios of three major diseases (tumor, respiratory disease, and trauma/toxicosis). With Shanghai serving as the "locomotive" driving the economy of the Yangtze River Basin, effective pollution control policies and a network of regional coordination are urgently needed in the globalization and ecological security of the entire area.  相似文献   
112.
Lee ES  Woo NC  Schwartz FW  Lee BS  Lee KC  Woo MH  Kim JH  Kim HK 《Chemosphere》2008,71(5):902-910
Release and spreading of permanganate (MnO(4)(-)) in the well-based controlled-release potassium permanganate (KMnO(4)) barrier system (CRP system) was investigated by conducting column release tests, model simulations, soil oxidant demand (SOD) analyses, and pilot-scale flow-tank experiments. A large flow tank (L x W x D=8m x 4m x 3m) was constructed. Pilot-scale CRP pellets (OD x L=0.05 m x1.5m; n=110) were manufactured by mixing approximately 198 kg of KMnO(4) powders with paraffin wax and silica sands in cylindrical moulds. The CRP system (L x W x D=3m x 4m x 1.5m) comprising 110 delivery wells in three discrete barriers was constructed in the flow tank. Natural sands (organic carbon content=0.18%; SOD=3.7-11 g MnO(4)(-)kg(-1)) were used as porous media. Column release tests and model simulations indicated that the CRP system could continuously release MnO(4)(-) over several years, with slowly decreasing release rates of 2.5 kg d(-1) (day one), 109 g d(-1) (day 100), 58 g d(-1) (year one), 22 g d(-1) (year five), and 12 g d(-1) (year 10). Mean MnO(4)(-) concentrations within the CRP system ranged from 0.5 to 6 mg l(-1) during the 42 days of testing period. The continuously releasing MnO(4)(-) was gradually removed by SOD limiting the length of MnO(4)(-) zone in the porous media. These data suggested that the CRP system could create persistent and confined oxidation zone in the subsurface. Through development of advanced tools for describing agent transport and facilitating lateral agent spreading, the CRP system could provide new approach for long-term in situ treatment of contaminant plumes in groundwater.  相似文献   
113.
Glutaric aciduria type I (GA I) is an autosomal recessively inherited inborn error with a defect of the enzyme glutaryl-CoA dehydrogenase (GCDH), which has never been diagnosed prenatally in Taiwanese patients. We present the prenatal sonographic findings and mutational analysis data of three children in two Taiwanese families. One patient from each family was diagnosed postnatally due to macrocephaly and neurological deterioration at 4 months and 10 months, respectively. The third child, sister of the first patient, was diagnosed prenatally at 11 weeks' gestation through chorionic villus sampling (CVS). Molecular analysis revealed that the fetus and child in Family 1 were homozygous for a common mutation, IVS10 -2A>C, which has not been reported in the Caucasian population. The patient in Family 2 was a compound heterozygote for IVS10 -2A>C and a novel mutation 749T>C (L238P). After genetic counseling, the couple decided to continue the second pregnancy. However, dilatation of quadrigeminal cistern (QC) and suspicious macrocephaly were noted at 30 weeks. Progressive dilatation of the QC associated with macrocephaly, fronto-temporal atrophy and wide space of perisylvian fissure were found in the follow-up scans. The affected girl was delivered at 37 weeks' gestation by cesarean section. Postnatal magnetic resonance imaging (MRI) studies confirmed the prenatal sonographic findings. With prenatal sonographic findings and mutational analysis presented in the present cases, the feasibility of prenatal diagnosis of GA I in high-risk pregnancy can not be overlooked. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
114.
Air samples in and around refinery areas were collected over a 3-year period. The results of the analysis for polynuclear aromatic compounds listed as priority pollutants by the United States Environmental Protection Agency are presented. The particulate matters in the air were collected on glass fiber filters using high volume samplers. These samples were later Soxhlet extracted with cyclohexane, and then extracted with DMSO/pentane for isolation of the polynuclear aromatic compounds. These extracts were then analyzed using gas chromatography-mass spectrometry for specified polynuclear aromatic compounds. It was found that much higher concentrations of these aromatic compounds were found in one refinery compared to another one. In general, the number of these priority pollutants detected and their concentrations were higher in sites inside the refineries relative to a site outside the refineries.  相似文献   
115.
Lebo JA  Huckins JN  Petty JD  Cranor WL  Ho KT 《Chemosphere》2003,50(10):1309-1317
Coarse (whole) and finely ground Ambersorb 1500 and coarse and fine coconut charcoal were compared as to their efficiencies in scavenging organic contaminants desorbed from sediment. Aqueous slurries of a test sediment spiked (1 ppm) with p,p-DDE (DDE), 2,2,5,5-tetrachlorobiphenyl (TCB), naphthalene (NAP), or phenanthrene (PHEN), and containing 1% levels of the test carbons were treated by shaking at 35 °C while exposed to clusters of low-density polyethylene membrane (detox spiders). Controls consisted of spiked sediments and detox spiders but no added carbon of any kind and thus represented unimpeded bioavailabilities (to the spiders). After the treatments––agitation periods from 2.5 to 60 h, depending on contaminant hydrophobicity––the exposed detox spiders were analyzed. The fine carbon of either type was more effective than its coarser variant in obstructing contaminant bioavailabilities. The finer variants of both carbons obstructed the bioavailabilities of NAP and PHEN equally well as did the coarser variants of both. Whole Ambersorb 1500 and coarse coconut charcoal were similarly ineffective in intercepting TCB and DDE. Ground Ambersorb 1500 obstructed virtually all bioavailability of all four contaminants and was far more effective than fine coconut charcoal in intercepting DDE and TCB. An additional experiment compared the effectiveness of ground Ambersorb 1500 and fine coconut charcoal in obstructing the bioavailabilities from sediment of a broad array of spiked organochlorine pesticides. The performance of ground Ambersorb 1500 was again found to be superior; the bioavailable levels of each of the 27 pesticides were markedly lower in the presence of ground Ambersorb 1500 than in the presence of fine coconut charcoal.  相似文献   
116.
Volatile organic compounds (VOCs) in urban atmosphere of Hong Kong   总被引:21,自引:0,他引:21  
Lee SC  Chiu MY  Ho KF  Zou SC  Wang X 《Chemosphere》2002,48(3):375-382
The assessment of volatile organic compounds (VOCs) has become a major issue of air quality network monitoring in Hong Kong. This study is aimed to identify, quantify and characterize volatile organic compounds (VOCs) in different urban areas in Hong Kong. The spatial distribution, temporal variation as well as correlations of VOCs at five roadside sampling sites were discussed. Twelve VOCs were routinely detected in urban areas (Mong Kok, Kwai Chung, Yuen Long and Causeway Bay). The concentrations of VOCs ranged from undetectable to 1396 microg/m3. Among all of the VOC species, toluene has the highest concentration. Benzene, toluene, ethylbenzene and xylenes (BTEX) were the major constituents (more than 60% in composition of total VOC detected), mainly contributed from mobile sources. Similar to other Asian cities, the VOC levels measured in urban areas in Hong Kong were affected both by automobile exhaust and industrial emissions. High toluene to benzene ratios (average T/B ratio = 5) was also found in Hong Kong as in other Asian cities. In general, VOC concentrations in the winter were higher than those measured in the summer (winter to summer ratio > 1). As toluene and benzene were the major pollutants from vehicle exhausts, there is a necessity to tighten automobile emission standards in Hong Kong.  相似文献   
117.
Environment, Development and Sustainability - Eliminating ultra-poverty has received particular attention of policymakers and scholars. The ultra-poor in mountainous regions often live on...  相似文献   
118.
Little research to date has focused on understanding employee motivation to share and hide knowledge. Using self‐determination theory, we tested the premise that knowledge sharing and hiding might be differentially motivated and that work design characteristics might influence the motivation to share knowledge with colleagues. In a panel survey of Australian knowledge workers and in a Chinese knowledge‐intensive organization, we asked knowledge workers, using time‐lagged designs, about perceptions of work design, motivation to share knowledge, and self‐reported knowledge sharing and hiding behaviors. Results, largely replicated across both samples, indicated that cognitive job demands and job autonomy were positively related to future reports of knowledge‐sharing frequency and usefulness via autonomous motivation to share knowledge. Unexpectedly, task interdependence was positively related to the three forms of knowledge hiding (evasive and rationalized hiding, and playing dumb) via external regulation to share knowledge. Implications for the design of jobs that motivate knowledge sharing and demotivate knowledge hiding are discussed.  相似文献   
119.
Using the failure mode and effects analysis, this study examined biomedical waste companies through risk assessment. Moreover, it evaluated the supervisors of biomedical waste units in hospitals, and factors relating to the outsourcing risk assessment of biomedical waste in hospitals by referring to waste disposal acts. An expert questionnaire survey was conducted on the personnel involved in waste disposal units in hospitals, in order to identify important factors relating to the outsourcing risk of biomedical waste in hospitals. This study calculated the risk priority number (RPN) and selected items with an RPN value higher than 80 for improvement. These items included “availability of freezing devices”, “availability of containers for sharp items”, “disposal frequency”, “disposal volume”, “disposal method”, “vehicles meeting the regulations”, and “declaration of three lists”. This study also aimed to identify important selection factors of biomedical waste disposal companies by hospitals in terms of risk. These findings can serve as references for hospitals in the selection of outsourcing companies for biomedical waste disposal.  相似文献   
120.
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