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481.
外源稀土La在沉积物中的形态及其生物可利用性   总被引:1,自引:0,他引:1  
将沉积物中的外源稀土La分为可溶解态、酸可提取态、有机质及硫化物结合态,研究了小球藻(Chlorella Vulgaris Beijerinck)对这三种形态La的生物可利用性.研究结果表明:这三种形态的La在沉积物中的含量与其在藻中的含量有很好的相关关系.其中可溶解态La的生物可利用性最大,这说明,沉积物中La的释放对其生物可利用性至关重要.  相似文献   
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A review of the use of planning and design briefs by local authorities in the United Kingdom was carried out in 1982–83 to test whether the role of the brief as an instrument of local policy and as a promotional tool in the development process was being fully exploited. The paper provides a state of the art review, presents a summary of the findings and offers some comments on the results. It concludes that most authorities now use briefs as part of their normal planning procedures, but that there is potential which is not yet being exploited.  相似文献   
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ABSTRACT: The desirable proportion of citizen input into policy making and the proper mechanism for that input engender substantial conflict in the water resources arena. Nevertheless, discussions of citizen participation in water policy formation generally occur within narrow perspectives both with regard to the issues involved and the alternative mechanisms by which that participation can be realized. This paper examines the historical and current contexts of the controversies and presents a discussion of the alternative processes for citizen influence - called linkage. The linkage processes discussed include direct participation, citizen advisory committees, the pressure group model, the electoral model and the bureaucratic model. Each linkage process is discussed in terms of who is considered the public, how the public influence works, the limitations of the process, and what available water policy-related data suggest regarding the adequacy of the process.  相似文献   
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Yu Qingkang 《Disasters》1982,6(3):202-206
This paper describes the necessity and the possibilities for mitigating the effects of natural disasters as exemplified by the Chinese experiences in Tangshan and Sichuan etc. With the dynamic viewpoint as a guiding concept the paper advocates the “prevention first” policy as well as planning strategies for human settlements in disaster-prone areas. It covers emergency and reconstruction planning as well as recommendations for prevention and mitigation planning. The paper also reviews the Chinese experience.  相似文献   
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21世纪住区建设   总被引:1,自引:0,他引:1  
面对世界发展趋势和中国建设高潮期,21世纪住宅建设需体现可持续发展,引入信息技术和新材料等高新技术,适应居住生活的发展。本文概述了当前世界发展趋势和国家住宅建设目标,住宅建设面临的科技问题,着重论述21世纪住区建设的规划设计原则。  相似文献   
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Comstock RD  Mallonee S 《Disasters》2005,29(3):277-287
The authors compared the effect of the 3 May 1999 F5 and 8 May 2003 F3 tornadoes on the community of Moore, Oklahoma, by canvassing damaged areas after both tornadoes and surveying residents. Significantly more 1999 than 2003 residents reported property damage and injuries. Television and tornado sirens were the most common warnings each year, however, more 1999 residents received and responded to television warnings. Importantly, storm shelters were used more frequently in 2003. Fifty-one per cent of residents who experienced both tornadoes took the same amount of protective action in 2003 as they had in 1999; 22% took less; and 27% took more. Residents who took less action said that the reason for doing so was inadequate warning and shelter. First-hand experience of tornadoes prompts people to heed warnings when adequate notification is received and to take effective protective action when adequate shelter is available.  相似文献   
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