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<正>1.Introduction And now we have Parxit.On 1 June 2017,President Trump issued the highly unpopular announcement that the United States will withdraw from the 2015 Paris Agreement on Climate Change.In this brief piece,I will try to explain the reasons for this nearly unprecedented act of foreign policy folly(Ronald Reagan did pull out of the Law of the Sea  相似文献   

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Conventional control strategies for volatile organic compounds (VOCs), a precursor to ozone, are identified. The control measures have been adopted by states in their efforts to attain the national ambient air quality standard for ozone by statutorily mandated deadlines. An inventory of viable control approaches for VOCs is presented, rather than a discussion of the approaches' comparative merits or of available alternatives. Focus is placed upon the technologies and control measures that U.S. EPA has identified as “reasonably available”, considering such criteria as effectiveness, costs, and associated energy and environmental impacts. These regulatory approaches include such strategies as vapor control in gasoline marketing, low solvent technologies and/or add-on control equipment for surface coating operations, and vehicle inspection and maintenance programs. By adopting these and additional control measures, as required, most states are projecting attainment of the ozone standard by 1987.  相似文献   

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Sustainable engineering is a conceptual and practical challenge to all engineering disciplines. Although the profession has experience with environmental dimensions of engineering activities that in some cases are quite deep, extending the existing body of practice to sustainable engineering by including social and cultural domains is a significant and non-trivial challenge. Nonetheless, progress is being made, as a recent study undertaken by the Center for Sustainable Engineering in the United States demonstrates.
Brad AllenbyEmail:
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ABSTRACT

The US National Science Foundation collects biennial data on views about science and technology (S&T). Analyses have typically focused on the degree to which demographics, knowledge, and attitudes predict S&T support or views about specific technologies or issues. Published efforts do not appear to have focused on identifying latent classes within the data. Initial analyses using latent profile analysis suggests that Americans can be categorized into six substantive audience groups when it comes to views about S&T. These groups vary by demographics, including scientific background and ideology, as well as in views about S&T. Post hoc analyses explore how “class-focused” analyses may provide additional insight beyond what can be obtained from “variable-focused” analyses.  相似文献   

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Because of the similarities in European and North American dietary exposure, it has been suggested that the order of magnitude higher body burdens in North Americans may be due to international variations in exposure via ingestion of indoor dust. Furthermore, ingestion of indoor dust has been suggested as a possible source of PBDEs in the blood serum of New Zealanders. Hence, polybrominated diphenyl ethers (PBDEs) were measured in domestic indoor dust from: Amarillo/Austin, Texas, US; Birmingham, UK; Toronto, Canada; and Wellington, New Zealand. Concentrations of BDE 209 in two UK samples were - at 520,000 and 100,000 ng g(-1) - the highest ever recorded in a domestic (or office) indoor dust sample. Median concentrations in ng g(-1) were: in Canada 620 and 560 for Sigmatri-hexa-BDEs and BDE 209 respectively; in New Zealand 96, BDE 209 not determined; in the UK 59 and 2,800; and in the US 1600 and 1300. With respect to BDE 209, concentrations were in the order: UK approximately US>Canada. For Sigmatri-hexa-BDEs, the order of concentrations was US approximately Canada>New Zealand approximately UK. Combined with principal component analysis of congener patterns, this suggests that, while North American dusts are contaminated by both Deca- and Penta-BDE commercial formulations, UK dusts are contaminated predominantly by Deca-BDE. The Octa-BDE formulation appears of minimal importance in accordance with available market demand figures. Despite the commercial formulations of PBDEs never having been manufactured in, nor imported into New Zealand, their presence in dusts from that country suggests international trade in PBDE-containing goods is an important pathway effecting their global distribution.  相似文献   

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A survey of selected radiochemical laboratories in the United States was conducted to estimate the relative numbers and types of analyses performed nationwide for the measurement of environmental radio-activity and to identify the regulatory requirements which affect the selection of analytical procedures and media. Information was sought from each laboratory regarding its parent facility, whether the laboratory performs its own analyses or contracts them out, and the technical and regulatory requirements for which the laboratory performed analyses.Analyses of water, air-particulate, and soil and sediment samples contribute the greatest workload. Many fewer vegetation, milk, diet, gas, or bioassay samples are processed. The most common measurements, especially for water, are for gross-α and gross-β activity. More than 50 different specific-radionuclide analyses are being performed with varying degree of regularity by the 161 laboratories surveyed. γ-spectrometry is the most frequently used method for specific-radionuclide analyses; the use of Ge (Li) detectors for γ-spectrometric measurements now exceeds that of NaI (Tl) detectors. Other radionuclides for which specific analyses are frequently performed by a large percentage (25–75%) of the laboratories include 90Sr, 131I, 226Ra, 238,239Pu, 234,235,238U, and tritium in water (HTO).  相似文献   

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美国政府在引导和规范国内气象经济发展的过程中,始终关注并有效抑制国有气象部门的垄断企图,及时果断地采取措施消除不利于气象事业顺应社会经济和技术发展要求的陈规陋习,适时坚定地扶持充满创造活力的民间资本的竞争努力.可以说,没有这种理智而清醒的管理理念,没有这种不昧于时的前赡眼光和超脱手法,没有这种不拘于内的国际视野和全球战略,是断难有其今天的作为的.我国气象经济的起步较美日等发达国家要晚近40年,更因发展思路不明至今已远远落后于诸多国家.如今面对国内社会经济发展对气象信息日益广泛而精细化的迫切需求,面对全球"气候政治"氛围愈益浓烈的全新形势.特别是"WTO'冲击渡带来的沉重的竞争压力,中国气象经济市场势必将在格局和规则方面进行重大调整.我国在推进气象服务市场化进程中亟需借鉴"美国经验",以确保我国气象事业的健康、协调、可持续发展.  相似文献   

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水权是现代水治理体系中的关键环节;合理的水权制度有助于水资源的优化配置。我国旧有的水资源管理模式中水权不明晰、水权制度尚未建立健全,因而无法适应市场经济发展和水资源高效可持续利用的需要。美国的水权制度与其发达的市场经济相适应,其经验可资借鉴。美国的水资源治理实践表明,建立在市场经济基础之上、以法律和制度为保障的水权制度,对于水资源的高效配置和可持续利用具有积极的促进作用。对水资源财产权的明晰界定是美国水权制度的基石;水权的取得及其权责范围均有明确的法律规定并受法律保护。在保护私有水权的同时,美国水权制度兼顾联邦和地方利益,同时避免外部性产生。各州对水权的确权和管理因各自人文和自然状况的差异而异,但对水资源"合理有益的使用"是各州共有的理念。美国的水治理理念正从偏重水资源的经济价值转向日渐重视水的环境及人文价值。社会公平、效率的增进、交易成本的降低是美国水权制度演进的内在动力。经历了漫长的历史演化,美国的水权管理体系已日臻成熟,但依旧存在不同层面的水权冲突,因此仍然在实践中不断修正调适。我国应学习借鉴美国水治理的有益经验,并积极探索美国经验的中国转化。本文对美国现行水权体系中水权的取得、水权的范围以及水权的变更与中止进行了系统总结,并在此基础上对中国的水权制度建设提出构想,包括:以立法确立和保障水权、建立市场导向的水价形成机制、运用水价杠杆实施有效的水资源需求管理、培育水权交易市场、构建区域性水权管理规范等。  相似文献   

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