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321.
南水北调中线工程对汉江中下游工业发展的影响 总被引:14,自引:3,他引:11
南水北调中线工程计划从丹江口水库向我国北方每年调水145亿m^3,汉江丹江口以下地区的水资源量将随之相应减少。汉江中下游地区是湖北省盐化工、机械、石油、食品、化肥、电力的重要生产地区,是湖北省的汽车工业走廊,其经济在湖北省占有举足轻重的地位。由于经济的迅速发展,下世纪工农业生产和人民生活对水资源的需求将从现在的140亿m^3增加到250亿m^3以上,需水量将达到水资源量的58%,潜伏着严重的水资源 相似文献
322.
323.
324.
Impacts on industry of Europe's emerging chemicals policy REACh 总被引:1,自引:0,他引:1
For Europe, a new regime in chemicals regulation is about to start. After the proposal of the European Commission concerning the Registration, Evaluation and Authorization of Chemicals (REACh) passed its readings in the European Parliament and some differences with the European Council of Ministers were resolved, the regulation will come into force in June 2007. This paper is focused on the question how serious the cost burdens for industry induced by REACh will be, and whether the New European Member States (NMS) which joined the European Union in May 2004 will be able to cope with the regulation. This evaluation has been done by assessing the legislative, administrative and economic framework in New Member States and by analysing real business cases in companies. The empirical showcase business impact studies are at the same time of interest for companies of EU-15 states, other European countries who may implement the regulation, and even for exporters of raw materials and chemicals outside Europe, who will also have to comply with REACh if they market in the European Community. The results give no indications that REACh adoption will bring significant drawbacks to companies in the NMS. The emerging regulation will bring challenges for individual companies, especially for small and medium-sized ones, but for the European chemical industry as a whole, there is no question that it will be able to cope with REACh burdens without losing its global competitiveness. 相似文献
325.
Marie-Claire Cordonier Segger 《Natural resources forum》2004,28(1):61-74
This article develops a practical proposal for progress on sustainable development law. It examines the prospects for an international sustainable development law to provide a framework for more effective, coherent governance. Sustainable development law is briefly defined and an analytical framework is provided. Different degrees of integration between economic, social and environmental law are described. Certain principles of international law related to sustainable development are also highlighted. It is argued that these principles may serve to guide law‐makers and jurists where social, economic and environmental law and policy conflict or overlap. Continuing, underlying questions of sustainable development governance are addressed and its global frameworks analysed. The article also focuses on the 2002 World Summit on Sustainable Development, held in Johannesburg in August‐September 2002, and its specific mandate for the United Nations Commission on Sustainable Development (UNCSD) to take related legal developments into account. The article advances a proposal: that governments, economic, social and environmental intergovernmental organizations and other actors establish a ‘network of inquiry’ with members from relevant groups, including legal and academic organizations, and other expert groups, in order to follow, research, analyse and debate legal developments in a balanced way. 相似文献
326.
金自学 《生态与农村环境学报》1996,(1)
根据对河西走廊中部荒漠植被的调查,对荒漠植被进行了分类及生态学描述,重点讨论了荒漠植被对改善河西走廊中部农村生态环境的作用,提出了保护和利用荒漠植被的措施及改善生态环境的途径。 相似文献
327.
职业高等教育法律专业的培养目标与专业课程设置初探 总被引:2,自引:0,他引:2
文章认为职业高等教育法律专业应根据自身特色规划培养目标和专业课程,尤其是从理论讲授、实际操作与社会实践三个方面对专业课程的设置作了较为深入的探讨. 相似文献
328.
观音堂库区水温变化对水生态环境影响的分析 总被引:4,自引:0,他引:4
本文用径流-库容比数法,对观音堂水库水体水温结构类型进行判断,用经验公式法和代表层水温法对观音堂水库水体水温结构和下泄水温进行了预测,预测结果表明:观音堂水库属分层型水库,在汛期表现出临时混合型的特点,水库下泄水使下游河道水温年内分布趋于均匀.这种水温变化,导致水库水质随水库深度增加而逐渐恶化,对水库下游河段水生生态系统产生不利影响。 相似文献
329.
L. Pereira C. Bastos T. Tzanov A. Cavaco-Paulo G. M. Guebitz 《Environmental Chemistry Letters》2005,3(2):66-69
A new strain of Trametes hirsuta was found to oxidize various cotton flavonoids. Here we show that laccases of this organism were responsible for oxidation
of the flavonoids morin, luteolin, rutin and quercetin. Out of two laccases produced by T. hirsuta (60.7 and 51.0 kDa) the more prominent 60.7 kDa laccase was purified and showed K
m and k
cat values of 75.5, 20.9 and 49.4 μM and 72.5, 96.3 and 32.7 s−1, hours on ABTS, syringaldazide and DMP, respectively. Pretreatment of cotton with the T. hirsuta laccase resulted in a whiteness increase of 8.5%. 相似文献
330.
二氧化硫与1—己烯的光化学反应动力学 总被引:1,自引:0,他引:1
利用GC/MS方法研究了SO2与1-己烯在无氧和有氧体系中光化学反应动力学,确定了SO2与1-己烯光化学反应的级数,给出了293-333K温度范围内总的反应速度常数K,以及K与温度的关系、反应的活化能和指前因子。另外,对反应物己醛和2-己酮的生成反应速度常数及其活化能也进行了计算和讨论。 相似文献