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This article compares, contrasts and analyzes energy use data in five worldwide manufacturing subsectors. It documents the differences in energy input/production output ratios among industries and among countries, and outlines areas of opportunity for implementing energy conservation measures. Special attention is given to the energy use record in developing countries and to assessing their particular problems and limitations in reducing industrial energy demand.
Cet article établit des comparaisons, fait ressortir des contrastes et présente une analyse des données sur l'utilisation de l'énergie dans cinq sous-secteurs industriels mondiaux. Il explique les différences qui existent dans le taux de rendement relatif aux entrées-sorties dans les industries et les pays. Il désigne des secteurs où peuvent s'appliquer des mesures de conservation d'énergie. Une attention toute particulière est accordée aux tendances d'utilisation de l'énergie dans les pays en développement et à revaluation des problèmes et limitations qu'ils confrontent à réduire la demande d'énergie industrille.
Este artículo analiza comparativamente la información sobre uso de energía en cinco ramas industriales. Documenta los ratios insumo/producto en varios países e indica las oportunidades para establecer medidas para la conservacón de energa. Se da especial atención a los patrones de uso de energía en los países en desarrollo y evalúa los problemas particulares y limitaciones para la reducción del uso de energía en la indústria.  相似文献   
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A divergence of values has become apparent in recent debates between conservationists who focus on ecosystem services that can improve human well‐being and those who focus on avoiding the extinction of species. These divergent points of view fall along a continuum from anthropocentric to biocentric values, but most conservationists are relatively closer to each other than to the ends of the spectrum. We have some concerns with both positions but emphasize that conservation for both people and all other species will be most effective if conservationists focus on articulating the values they all share, being respectful of divergent values, and collaborating on common interests. The conservation arena is large enough to accommodate many people and organizations whose diverse values lead them to different niches that can, with good will and foresight, be far more complementary than competitive. Los Nichos Complementarios de los Conservacionistas Antropocéntricos y Biocéntricos  相似文献   
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Chytridiomycosis, caused by Batrachochytrium dendrobatidis (Bd), is widespread among amphibians in northeastern North America. It is unknown, however, whether Bd has the potential to cause extensive amphibian mortalities in northeastern North America as have occurred elsewhere. In the laboratory, we exposed seven common northeastern North American amphibian species to Bd to assess the likelihood of population-level effects from the disease. We exposed larval wood frogs (Lithobates sylvaticus) and postmetamorphic frogs of six other species to two different strains of Bd, a northeastern strain (JEL404) and a strain that caused die-offs of amphibians in Panama (JEL423), under ideal in vitro growth conditions for Bd. Exposed American toads (Anaxyrus americanus) all died; thus, this species may be the most likely to die from Bd-caused disease in the wild. Both Bd strains were associated with mortalities of wood frogs, although half the metamorphs survived. The Bd strain from Panama killed metamorphic green frogs (L. clamitans), whereas the northeastern strain did not, which means novel strains of Bd may lead to death even when local strains may not. No mortality was observed in four species (bullfrogs [L. catesbeianus], northern leopard frogs [L. pipiens], spring peepers [Pseudacris crucifer], and blue-spotted salamanders [Ambystoma laterale]) and in some individuals of green frogs and wood frogs that we exposed. This finding suggests these six species may be Bd vectors. Our results show that systematic exposures of amphibian species to Bd in the laboratory may be a good first step in the identification of species susceptible to Bd-caused declines and in directing regional conservation efforts aimed at susceptible species.  相似文献   
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A survey of academic programs in air pollution control was made. Results from the 127 schools reporting are tabulated by state. Faculty involved in air pollution instruction are identified. Some conclusions and recommendations are presented.  相似文献   
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The principle of fabric filtration has only recently been accepted for fossil fuel fired boiler particulate emissions control. Information on design criteria is, therefore, limited. The paper provides data on the few installations where baghouses have been installed and successfully operated. The general conclusion is that a strong relationship exists between air to cloth ratio and bag life.  相似文献   
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