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951.
Terence R. Lee 《Natural resources forum》1979,3(4):401-416
This article discusses some recent developments in water management in Latin America. It is based on research done during the joint CEPAL/UNEP project on Water Development and the Environment. The author discusses the changes in water use occurring in Latin America in general, the contemporary relationship with the water resource in four major metropolitan centres, Bogotá, Colombia, Lima, Peru, and Sāo Paulo and Rio de Janeiro, Brazil. On the basis of the general and specific experiences described, general conclusions are drawn as to styles of water management current in the region and adjustments to the problem posed by the emergence of very large metropolitan concentrations of population and economic activity. Cet article reprend des développements récents en matière de gestion des ressources en eau en Amérique latine. II se base sur des recherches effectuées au cours de l'exécution du projet conjoint CEPAL/PNUE sur la mise en valeur des ressources en eau et de l'environnement. L'auteur discute des modifications intervenues dans l'utilisation des ressources en eau en Amérique latine en général et le rapport qui existe actuellement entre les ressources en eau et quatre centres principaux urbains (Bogota en Colombie, Lima au Pérou, et Sāo Paulo et Rio de Janeiro au Brésil). Sur la base des experiences générales et particulières décrites, des conclusions génèrales sont tirées quant aux modes de gestion actuelle des ressources en eau dans la région et aux améliorations apportées au problème créé par l'apparition d'énormes agglomérations urbaines à activité économique intense. Este artículo trata sobre algunos desarrollos recientes en la administración del uso de recursos de agua en Latinoamérica. El artículo está basado en la investigación realizada en el proyecto conjunto CEPAL/PNUMA sobre Desarrollo de Agua y el Medio Ambiente. El autor analiza los cambios que están ocurriendo en el uso de recursos de ague en Latinoamérica en general y las relaciones entre los recursos de agua y los usos en cuatro centros metropolitanos: Bogotá, Lima, Sāco Paulo y Rio de Janeiro. Basándose en descripciones de experiencias generales y específicas, se extraen conclusiones sobre los estilos de la administración de recursos de agua existentes en la región y sobre la solución a los problemas planteados por la emergencia de grandes concentraciones metropolitanas de población y actividad económica. 相似文献
952.
Choi MS Lin XJ Lee SA Kim W Kang HD Doh SH Kim DS Lee DM 《Journal of environmental radioactivity》2008,99(8):1319-1323
The concentrations of naturally occurring radioisotopes ((232)Th, (228)Th, (230)Th, (228)Ra, (226)Ra, and (40)K) in typical Korean foods were evaluated. The daily intakes of these radioisotopes were calculated by comparing concentrations in typical Korean foods and the daily consumption rates of these foods. Daily intakes were as follows: (232)Th, 0.00-0.23; (228)Th, 0.00-2.04; (230)Th, 0.00-0.26; (228)Ra, 0.02-2.73; (226)Ra, 0.01-4.37 mBq/day; and (40)K, 0.01-5.71 Bq/day. The total daily intake of the naturally occurring radioisotopes measured in this study from food was 39.46 Bq/day. The total annual internal dose resulting from ingestion of radioisotopes in food was 109.83 muSv/y, and the radioisotope with the highest daily intake was (40)K. These values were same level compiled in other countries. 相似文献
953.
954.
Lee Hyun-Kyu Choi Jung-Weon Kim Jin-Hee Kim Cho-Rong Choi Sang-June 《Environmental science and pollution research international》2021,28(31):42014-42023
Environmental Science and Pollution Research - Composite beads consisting of Ca alginate mixed with zinc ferrocyanide (ZnFC) and Cyanex 272 were synthesized in order to selectively adsorb Cs+ and... 相似文献
955.
Journal of Polymers and the Environment - A set of novel biocompatible aliphatic–aromatic nanocomposites, including numerous acrylic acid-grafted poly(butylene carbonate-co-terephthalate)... 相似文献
956.
Tien-Chun Cheng Tzu-Yuan Huang Chi-Fu Chen Sheng-Wei Lee Jeng-Kuei Chang 《International Journal of Green Energy》2016,13(15):1640-1647
The performance of an intermediate-temperature proton-conducting solid oxide fuel cell (pSOFC) hybrid system is investigated in this work. The hybrid system consists of a 20-kW pSOFC, a micro gas turbine (MGT), and heat exchangers. Heat exchangers are used to recover waste heat from pSOFC and MGT. The performance of the system is analyzed by using Matlab/Simulink/Thermolib. Flow rates of air and hydrogen are controlled by assigning different stoichiometric ratio (St). St considered in this study is between 2 and 3.5 for air, and between 1.25 and 1.45 for hydrogen. Results show that the combined heat and power (CHP) efficiency increases as the fuel St decreases or air St increases. This is because lowering fuel St means fewer fuel will be wasted from the fuel cell stack, so the CHP efficiency increases. On the other hand, as air St increases, the amount of recovered waste heat increases, so does the CHP efficiency. 相似文献
957.
The effect of clean energy regulations and incentives on green jobs: panel analysis of the United States, 1998–2007 下载免费PDF全文
Taedong Lee 《Natural resources forum》2017,41(3):145-155
‘Green jobs’ are often presented as a simultaneous solution for the economic downturn and the environmental crisis, particularly as they relate to sustainable development in energy and climate change. Federal, state, and municipal authorities have employed a variety of policy tools to boost job creation within their jurisdictions. This study focuses on the role that state policies play in creating green jobs. It examines two generic policy tools – regulations and incentives – each of which can be aimed at advancing energy efficiency or renewable energy production, and assesses the relative impact they have had on generating green jobs. In order to measure this impact, we utilize panel data compiled by the Pew Charitable Trusts, which contain a state‐level count of green jobs from 1998 to 2007. The results of the analysis suggest that regulations, particularly those that mandate action on renewable energy, are likely to increase the number of private sector green jobs in states. Regulations with clear guidelines and targets tend to reduce uncertainty in business, and can lead to increased private sector investment and job availability. This study provides practical lessons regarding the type and design of policy instruments and regulations on renewable energy, which effectively encourage green job growth. 相似文献
958.
Environmental degradation caused by human activities is of concern to society, government, industry, companies, and the people who are able to enjoy improved lifestyles because of industrial activities. However, all of these parties also have a responsibility to support and conserve the environment and act responsibly toward the earth. This article, which includes a systematic literature review and draws upon the authors’ practical experience, summarizes the benefits, motives, and difficulties in implementing environmental management systems using the International Organization for Standardization's (ISO) 14001 framework. 相似文献
959.
Philip R. Berke Matthew L. Malecha Siyu Yu Jaekyung Lee Jaimie H. Masterson 《Journal of Environmental Planning and Management》2019,62(5):901-920
Planning for hazard mitigation is frequently detached from other planning activities that influence development patterns in hazardous areas. Consistent integration of mitigation reduces hazard vulnerability for people and the built environment. We apply a plan integration for resilience scorecard in six US coastal cities to evaluate the integration of local networks of plans and the degree to which they target areas most vulnerable to flooding hazards. We find that plan integration scores vary widely across the six cities, and that some plans actually increase vulnerability in hazard zones. Policies also frequently support mitigation in areas with low vulnerability, rather than in areas with high vulnerability. The plan integration for resilience scorecard can generate information to improve hazard planning by allowing planners to identify conflicts between plans, assess whether plans target areas that are most vulnerable, and better inform decision makers about opportunities to mainstream mitigation into multiple sectors of planning. 相似文献
960.
Christopher J. Bellucci Mary E. Becker Mike Beauchene Lee Dunbar 《Environmental management》2013,51(6):1274-1283
Bioassessments have formed the foundation of many water quality monitoring programs throughout the United States. Like many state water quality programs, Connecticut has developed a relational database containing information about species richness, species composition, relative abundance, and feeding relationships among macroinvertebrates present in stream and river systems. Geographic Information Systems can provide estimates of landscape condition and watershed characteristics and when combined with measurements of stream biology, provide a useful visual display of information that is useful in a management context. The objective of our study was to estimate the stream health for all wadeable stream kilometers in Connecticut using a combination of macroinvertebrate metrics and landscape variables. We developed and evaluated models using an information theoretic approach to predict stream health as measured by macroinvertebrate multimetric index (MMI) and identified the best fitting model as a three variable model, including percent impervious land cover, a wetlands metric, and catchment slope that best fit the MMI scores (adj-R 2 = 0.56, SE = 11.73). We then provide examples of how modeling can augment existing programs to support water management policies under the Federal Clean Water Act such as stream assessments and anti-degradation. 相似文献