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61.
化学品风险评估是化学品管理的核心科学依据和主要技术手段,构建化学品风险评估制度对我国加强化学品管理具有重要意义。总结了国际上化学品风险评估制度体系在法规制度建设、指南、模型和数据库开发、风险评估实践等方面的进展和经验,分析了我国化学品风险评估在制度建设、指南标准、科学研究和信息收集方面取得的进展和存在的问题,提出了从立法制度建设、技术体系构建、基础能力建设和调查监测完善等方面建设我国化学品风险评估制度的建议。 相似文献
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Yang Yuwen Yang Wenya .Research Center for Circular Economy Nankai University Tianjin China; . 《中国人口.资源与环境(英文版)》2011,(4):77-81
The aim of this study is to examine the relationship between environment and personal well-being using a sample of 562 urban employees from three cities in Liaoning province in the People’s Republic of China.In contrast to previous studies,this study controlled positive affectivity (PA),negative affectivity (NA),job satisfaction and Big Five personality traits.In addition,the research variables of personal well-being index (PWI),positive affectivity,negative affectivity,job satisfaction,Big Five,and environmental satisfaction are measured with multi-item scales.The research finds that environmental satisfaction is positively related to personal well-being,suggesting that improvement of the natural surroundings in the cities can improve people’s well-being. 相似文献
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Qiu Ling Fang Chuanglin Shen Yuming Liu Xiaoli .Institution of Geographic Sciences Natural Resources Research Chinese Academy of Sciences Beijing China; 《中国人口.资源与环境(英文版)》2011,(4):82-89
The five central cities-Beijing,Tianjin,Shanghai,Guangzhou and Shenzhen-of the three most important strategic regions in China,namely Beijing-Tianjin-Hebei metropolitan region,the Yangtze River Delta and the Pearl River Delta,are taken as a comparative analysis on urban producer services’ competitiveness,especially focusing on the comparative advantages and disadvantages of producer services in Beijing.Firstly,based on an integrated indicator system including one objective hierarchy,four standard hierarchies and 35 indicator hierarchies,the study applies factor analysis model and analytic hierarchy process model reformed by entropy technology to measure the comprehensive competitiveness of producer services in the above five cities.Secondly,Beijing has comparative advantages of capital resource,industrial base,scientific research resource and market scale,since it takes the first place of the five cities in the comprehensive competitiveness of producer services,the competitiveness of industrial development,business environment and living environment,only inferior to Shanghai in the competitiveness of talent capital.Thirdly,Beijing has comparative disadvantages in the level of producer services development,urban innovation capability and living environment.Finally,five proposals are put forth to enhance the competitiveness of producer services in Beijing,namely perfecting the system of laws and statutes,supporting the development of industry association,implementing scientific development planning,introducing preferential fiscal and taxation policies and strengthening human capital reserve. 相似文献
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Zhang Mingxi 《中国人口.资源与环境(英文版)》2011,9(2):84-89
Levying carbon tax is conducive to reducing carbon dioxide emissions and protecting the environment.The author firstly reviewed some relevant empirical studies on carbon tax both home and abroad,and then established the CGE model and simulated levying carbon tax in China.The study found that levying carbon tax would have little impact on China’s economy:in a short-term,China’s GDP might decrease by 0.51%,while in a long-term it might decrease by 0.08%;however,the carbon dioxide emissions would be substantially reduced.Meanwhile,levying carbon tax has some negative impact on the output of each industry in the very economic structure;of this,the mineral extractive industries would be influenced the most.Then the author summarized experience of levying carbon tax in foreign countries. 相似文献
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基于GIS与RUSLE的武陵山区小流域土壤侵蚀评价研究 总被引:1,自引:0,他引:1
以长江中下游武陵山区女儿寨小流域为研究区,基于数据观测积累及实地调查采样等方法,计算了研究区降雨侵蚀力、土壤可蚀性等因子,运用GIS与RUSLE评价了流域土壤侵蚀强度并分析了其与土地利用方式、海拔高度的关系。结果表明,流域平均土壤侵蚀强度为78844 t/(km2·a),属微度侵蚀,流域面积9518%的范围发生轻度以下的侵蚀,强烈以上侵蚀仅占1.19%。从土地利用类型来看,耕地、果园侵蚀强度较大,均达到中度侵蚀,有林地除竹林地为轻度侵蚀外均属微度侵蚀,耕地、果园、竹林地是今后水土流失防治的主要地类。不同海拔高度中,低海拔(200~400 m)区域侵蚀量占到流域侵蚀总量的6442%,是水土流失防治的重点地带。研究为应用修正通用土壤流失方程在武陵山区进行土壤侵蚀评价提供范例,为研究区防治土壤侵蚀和流域管理规划决策提供相应参考 相似文献
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To promote modern agricultural equipment level is one characteristic of constructing and developing modern agriculture in China.This paper makes up stepwise linear regression analysis model of influence factors of modern agricultural equipment level,and chooses rural labor,per capita income of rural residents,rural investment,proportion of people at secondary education level and at higher level in per hundred rural labor force and arable land area as independent variables,and total power of machine as induced variable.The major results show that the relativity of modern agricultural equipment level,rural investment and education level of peasants is remarkable,and they are the major influence factors of modern agricultural equipment level.Raising investment level of rural infrastructure construction as well as and research and development and promotion of advanced and applicable modern agricultural equipment,improving quality and education level of peasants can accelerate the development of China’s modern agricultural equipment effectively in the process of agricultural sustainable development. 相似文献
69.
全球气候变暖已经成为不容置疑的事实,同时外来入侵植物对入侵地的生态环境造成严重的危害,外来入侵植物可能对温度升高做出积极地响应。文章研究了不同温度(22、26和30℃)处理对入侵植物三叶鬼针草(Bidens pilosa L.)种子萌发、幼苗生物量分配及化感作用的影响,探讨三叶鬼针草对全球气候变暖的响应策略。结果表明;温度为22和26℃比30℃有利于三叶鬼针草种子的萌发。温度升高显著增加三叶鬼针草的株高、生物量和叶面积,三叶鬼针草幼苗增加对茎和叶的生物量投资。同时相同浓度的三叶鬼针草水浸提液对马唐(Digitaria sanguinalis(L.)Scop)和牛筋草(Eleusine indica(L.)Gaertn)的化感作用随着温度升高而增强。研究表明:温度升高促进了三叶鬼针草的生长,改变生物量分配模式同时增强了对受体植物的化感作用。温度升高可能是促进三叶鬼针草入侵的生态环境因子之一,未来全球气温变暖可能使其入侵加剧。 相似文献
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通过对膨润土的羟基铝改性实验大大提高了膨润土对染料废水的处理效率。实验结果表明:改性膨润土对变色酸有很好的去除效果,对H酸有较好的去除效果,对T酸处理效果一般,对吐氏酸几乎没有效果。 相似文献