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151.
PCN congeners were analyzed in marine and riverine sediments of the Laizhou Bay area, North China. Concentrations of PCNs ranged from 0.12 to 5.1 ng g1 dry weight (dw) with a mean value of 1.1 ng g1 dw. The levels of PCNs varied largely, with industrial group approximately ten folds higher than those of the rural in riverine sediment. A strong impact by direct discharge from local factories was suggested. Similar compositional profiles were found within groups. High resemblance of compositional profiles between industrial samples and Halowax 1014 was observed. It was indicated that PCNs in riverine sediments were mainly from release of industrial usage, with additional contributions from industrial thermal process at certain sites. In marine sediments, it was suggested that PCNs along the coast of Laizhou Bay were mainly controlled by riverine input. While in the central bay, PCN distributions were possibly impacted by combined multiple factors.  相似文献   
152.
Dechlorane Plus (DP) has been determined in surface sediments from three Chinese coastal bays, e.g. Jiaozhou, Sishili and Taozi Bay in North China. DP concentrations ranged from <1.2 to 187 pg g−1 dry weight (dw) (mean: 24.7 pg g−1 dw) in Jiaozhou Bay, <1.2 to 135 pg g−1 dw (mean 69.9 pg g−1 dw) in Sishili Bay and <1.2 to 66.7 pg g−1 dw (mean: 40.4 pg g−1 dw) in Taozi Bay, respectively. Additionally, two dechlorinated species were quantified, which accounted for 0.6-5.1% of the ∑DP concentration.The fsyn values (syn-isomer/(syn- + anti-isomer)) in sediments from Jiaozhou Bay (mean 0.29) were close to the technical DP mixture (0.2-0.4), probably indicating local inputs of DP. In contrast, sediments in Sishili and Taozi Bay showed much lower fsyn values (mean 0.16). During transportation the DP isomers are subject to stereo selective degradation which partly resulted in the relative enrichment of anti-DP in coastal sediments.  相似文献   
153.
西北黄土地区现场石油污染土壤生物修复研究   总被引:2,自引:0,他引:2  
通过在陕北安塞油田某废弃油井建立中试试验基地,以实验室中筛选分离得到的高效降解石油的优势菌为添加的高效菌,研究土壤石油初始浓度、营养物质和高效菌对石油降解的影响.结果表明:(1)在各土壤石油初始浓度下,石油降解率总体均随降解时间的延长而升高.在土壤石油初始质量浓度为15.34 g/kg下,72 d时石油降解率为47.8...  相似文献   
154.
With the increasing number of recycling mishaps in connection with waste electronic and electrical equipment (WEEE) in the People's Republic of China, it is imperative that the handling and recycling of WEEE be sufficiently regulated in China. Regulations covering three major issues, namely, take-back issues, controls on hazardous substances in WEEE and the assurance of good environmental management in WEEE plants, were promulgated between 2006 and 2008. The evaluation in this country report shows that few of these regulatory measures have performed satisfactorily in terms of enforcement, of public acceptance and of environmental concerns. In brief, the take-back requirements and the associated financial responsibilities are only vaguely defined; the control on hazardous substances and the so-called "environmental expiry date" requirements cannot be properly enforced, and the resources needed to ensure the satisfactory enforcement of the environmental abatement and pollution control requirements in WEEE plants are overwhelming. In addition, the use of a "multiple enforcement body" approach to the control of hazardous substances in WEEE is an indication that the Chinese government lacks the determination to properly enforce the relevant legal requirements.  相似文献   
155.
A solid-phase microextration-based sampling method was employed to determine the concentrations of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its metabolites, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethene (DDE) and 1-chloro-2,2-bis(p-chlorophenyl)ethene (DDMU), in two estuarine bays, Daya Bay and Hailing Bay, of South China. Six DDT components including p,p′-DDT, o,p′-DDD, p,p′-DDD, o,p′-DDE, p,p′-DDE, and p,p′-DDMU were detected in Hailing Bay, while only p,p′-DDD was found in Daya Bay. p,p′-DDD was the most abundant DDT component in both bays, sharply different from the previous finding in the water column of the Palos Verdes Shelf, California, USA that p,p′-DDE was prevalent. In addition, the occurrence of p,p′-DDMU (with a range of 0.047-0.21 ng/L in Hailing Bay) has not been reported around the globe, and its presence in our study region appeared to stem from dehydrochlorination of p,p′-DDD, favored under aerobic conditions, but further investigations are clearly needed to confirm the mechanism for generation of DDMU in estuarine environments.  相似文献   
156.
Endosulfan in China 1—gridded usage inventories   总被引:9,自引:0,他引:9  
Background, aim, and scope  Endosulfan, an organochlorine pesticide (OCP), is genotoxic in mammalian cells and generally considered to be toxic and classified by the World Health Organization and the US Environmental Protection Agency as priority pollutants and a nominator for inclusion in a future iteration of the persistent organic pollutants treaty. Endosulfan is a currently used pesticide and still being used worldwide. The general trend of total global endosulfan use has increased continuously since the first year when this pesticide was applied. It is critical to create national endosulfan usage/emission inventories for China to carry out source–receptor relation analysis, risk assessment, and other research related to endosulfan in this country. Chinese inventories have been published for some OCPs, such as technical HCH and lindane, DDT, and chlordane; for endosulfan, however, there has not been any usage inventory available on any scales (national or provincial), although endosulfan has been widely used since 1994 in this country. This is the first part of the work. The goal of this paper is to quantify the historical production and usage of endosulfan in China and to compile gridded historical usage inventories of endosulfan for this country. Based on these usage inventories, emission and residue inventories will be created, which is the goal of the second part of the work. Materials and methods  Due to the lack of national production and usage information of endosulfan in China, a method to estimate the use of endosulfan was developed. First, information of crops on which endosulfan is applied and average endosulfan use and annual application frequencies of endosulfan on these crops were collected. Secondly, usage of endosulfan on each crop was estimated using the national cropland area for each province from Chinese government reports. Finally, with the help of GIS (geographic information system), the usage data of this insecticide was allocated to a grid system, with a 1/4° longitude by 1/6° latitude resolution, with a size for each grid cell of approximately 25 km by 25 km. Results and discussion  The use of endosulfan in agriculture in China started on cotton in 1994, and on wheat, tea, tobacco, apples, and other fruits in 1998. Endosulfan usage on cotton, wheat, tea, tobacco, and apples in China has been estimated to be approximately 25,700 t between 1994 and 2004. The province with the highest usage of endosulfan is Henan Province, with a total usage reaching 4,000 t, followed by the uses in Xinjiang Autonomous Region (3,200 t), Shandong Province (3,000 t), Hebei Province (2,100 t), and Anhui Province (1,900 t). Gridded usage inventories of endosulfan at a 1/4° longitude by 1/6° latitude resolution have been created, which indicate that the intensive endosulfan use was in the south of Hebei Province, west of Shandong Province, east of Henan Province, north of Anhui Province, east of Jiangsu Province, and some areas in Yunnan Province and Xinjiang Autonomous Region. General agreement has been found between the usage data from our estimation and the small amount of usage data published in China. Conclusions  This is the first national gridded endosulfan usage inventory produced for China. The annual applications of endosulfan from 1994 to 2004 in China were estimated based on the total areas of major crops, on which endosulfan was applied, and spatial distribution of the application was generated at provincial and prefecture levels. With the help of GIS, endosulfan usage based on prefecture was transferred to a 1/4° longitude by 1/6° latitude gridding system. The satisfaction of the inventories was supported by the consistence between the estimation of the annual usage and the reported annual production of endosulfan. Recommendations and perspectives  This gridded endosulfan usage inventory created in this study will be improved upon availability of new information of endosulfan. The usage inventories can be used to create gridded emission and residue inventories for this insecticide. It is believed that this work will pave the way for further endosulfan studies in China and beyond.  相似文献   
157.
我国旅游教育发展的初步研究   总被引:1,自引:0,他引:1  
我国旅游业的高速发展推动了旅游教育事业快速发展,同时也给旅游教育提出了更高的要求和挑战.在文献分析和整理的基础上,简要梳理了改革开放以来我国旅游教育发展所取得的显著成就,归纳出旅游专业教育在培养目标和模式、教学观念、课程设置、教学方法、师资力量、就业等方面存在的问题,最后提出了未来旅游教育发展的对策和建议.  相似文献   
158.
Household consumption is one of the important factors that induce COL emission. Based on input-output model, this article calculated the intensity of CO2 emission of different income groups and seven provinces in China, and then estimated total CO2 emission induced by urban household consumption from 1995 to 2004 in China based on statistic data of household living expenditure. The results show that CO2 emission per capita induced by household consumption had increased from 1583 to 2498 kg CO2 during 1995-2004. The ratio of consumption-induced CO2 emission to total CO2 emission had risen from 19% to 30% in the past decade. Indirect CO2 emission accounted for an important part of the consumption-induced emission, the ratio of indirect emission to consumption-induced emission had risen from 69% to 79% during the same period. A significant difference in consumption-induced CO2 emission across different income groups and different regions has been observed. COs emission per capita of higher income groups and developed regions increased faster than that of lower income groups and developing regions. Changing lifestyle has driven significant increase in CO2 emission. Especially, increases in private transport expenditure (for example, vehicle expenditure) and house building expenditure are key driving factors of growth in consumption-induced COL emission. There are big differences in the amount of CO2 emission induced by change in lifestyle across different income groups and provinces. It can be expected that lower income households and developing regions will increase consumption to improve their livings with income growth in the future, which may induce much more CO2 emission. A reasonable level of CO2 emission is necessary to satisfy human needs and to improve living standard, but a noticeable fact is that CO2 emission per capita induced by household consumption in developed areas of China had reached a quite high level. Adjustment in lifestyle towards a low-carbon society is in urgent need.  相似文献   
159.
The wide application of new information and communication technologies (ICTs) has been argued to be critical to business success of small and medium-sized enterprises (SMEs), especially to those in the developing countries. Drawing upon existing literature, this article will examine the determinants of ICTs application in SMEs in China based on data collected from interviews with top managers and/or owners of 70 SMEs. We identify 20 factors affecting ICTs application in SMEs in China and divide them into four broad categories, namely pressures, firm specific factors, technical factors and local milieu. We also pay special attention to the Chinese business environment affecting ICTs application. Our analysis shows that local ICT infrastructure, external pressures from competitors and ICT knowledge of employees are the determinants of Internet application by SMEs, while product characteristics and market target are important factors of e-commerce adoption.  相似文献   
160.
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