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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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A joint conference for the fifth straight year cosponsored by the Air & Waste Management Association’s EM-3, EM-4, and ITF-2 technical committees, and the Atmospheric Research and Exposure Assessment Laboratory (AREAL) of the U.S. Environmental Protection Agency, was held in Raleigh, North Carolina, May 1–4, 1990. The technical program consisted of 187 presentations, held in 20 technical sessions, on recent advances in the measurement and monitoring of toxic and related pollutants found in ambient and source atmospheres. Covering a wide range of measurement topics and supported by 66 exhibitors of instrumentation and consulting services, the symposium was attended by more than 850 professionals from the United States and other countries. This overview highlights a selection of the technical presentations. A synopsis of the keynote address to the symposium is also included.  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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This study was undertaken to identify seasonal and source effects on the par-ticulate contaminants of the New York City atmosphere and ultimately to relate the concentrations of these contaminants to the tissue concentrations in residents of New York City. Continual weekly samples of particulates have been collected at three stations in the New York area on 8 by 10 in. glass fiber filters at a flow rate of 20 cfm.

The sample is ashed with a Tracerlab Low Temperature Asher and leached with nitric acid. Metals analyzed by the Atomic Absorption method include Pb, V, Cd, Cr, Cu, Mn, Ni, and Zn. Lead-210, total particulate, and benzene and acetone soluble organic material are also determined.

The data have been related to various meteorological parameters over a one year period to define significant seasonal and source influences, as well as site to site variations. Very significant inverse correlations to temperature are obtained for suspended particulates, vanadium, and nickel at both Manhattan and Bronx sites. Particulates show a less significant inverse correlation to temperature In lower Manhattan. Oil-fired space heating sources appear to account for as much as 50% of the particulates in the Bronx at the peak demand period.

Lead, copper, and cadmium show a general inverse correlation to average wind speed, and a direct correlation to temperature. The latter is most likely due to an inverse relation between wind speed and temperature. The heating season input for particulates, vanadium, and nickel is so great as to overcome most of the dilution effect due to winds. The other elements having more constant nonseasonal inputs, definitely reflect the effects of the wind.

The most significant site effect occurs with cadmium, which has a concentration in lower Manhattan three times that of the Bronx over a period of six to seven months in the summer and fall. The differences observed for cadmium and particulates may be explained by emission source factors which have not as yet been studied.  相似文献   
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