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911.
Ventilation requirements in occupied spaces have traditionally derived largely from odor control. The requirements have rested on the notion that an environment that seems subjectively acceptable to a visitor will in fact be healthful and comfortable for both visitor and occupant alike. Ventilation requirements have derived secondarily from criterion concentrations of notable contaminants (e.g., carbon dioxide). The present investigation looked again at both sensory (odor, irritation) and physical criteria of acceptability, paying particular attention to the difference between smoking and nonsmoking occupancy in a well-controlled environmental chamber. More than 200 persons (visitors) made judgments of odor intensity and acceptability under various conditions of occupancy (up to 12 nonsmoking occupants; a temperature of up to 25.5°C; up to 16 cigarettes smoked per hour). The results implied that under nonsmoking conditions and moderate humidity only about 7.5 cfm (3.8 L sec−1) of fresh air per occupant sufficed to satisfy visitors, but that under smoking conditions at least 5 times as much fresh air is necessary. Our estimate of ventilation requirements for smoking were derived in part from measurements of carbon monoxide and total suspended particulate (TSP) mass concentration. Levels of TSP achieved during realistic smoking and ventilation rates exceeded levels deemed acceptable outdoors. Surfaces in the chamber played an important role in the elimination of particles, presumably via adsorption. Use of an electrostatic precipitator could keep TSP levels under control. Nevertheless, it remains to be seen whether control of TSP will eliminate the need for enormous ventilation for odor control during smoking occupancy.  相似文献   
912.
913.
The U. S. Nuclear Regulatory Commission has established a Working Group to evaluate methods for improving control of devices containing radioactivity in industry. These devices include radiography equipment and moisture/density gauges. The Working Group was the result of a number of incidents in which these devices were inadvertently shipped to scrap dealers and steel recycling facilities. The resulting release of radioactivity when the devices were processed has cost millions of dollars to clean up. This article discusses the Working Group's conclusions and the potential impact of these conclusions on the remediation industry. It also makes recommendations for both current and prospective owners of devices containing radioactivity on how to prepare for regulatory changes likely to occur as a result of the Working Group's conclusions.  相似文献   
914.
This paper relates the long-neglected Douglas/New Age texts to contemporary concerns at the relationship between economic activity and environmental degradation. Although completed by the early 1920s, these texts anticipated the adverse social and environmental impacts of an increase of centralisation and globalisation of finance upon local policy formation.  相似文献   
915.
Assessing the genetic structure of natural populations differentially impacted by anthropogenic contaminants can be a useful tool for evaluating the population genetic consequences of exposure to pollution. In this study, measures of genetic diversity at variable-number-tandem-repeat loci in six dandelion populations (3 urban and 3 rural) showed patterns that may have been influenced by exposure to environmental contaminants. Mean genetic similarity among individuals within a population was significantly and positively correlated with increasing levels of airborne particulate matter ( 10 m, PM10) and soil concentrations of four metals (Cd, Fe, Ni and Pb). In addition, mean genetic similarity was always significantly higher at the urban sites compared to rural sites. There was a significant negative correlation between the number of genotypes at a site and increasing amounts of PM10, concentrations of five soil metals (Cd, Cu, Fe, Ni and Pb), leaf tissue levels of Fe and a significant positive correlation between the extent of clonality at a site and levels of PM10 and soil concentrations of five metals (Cd, Cu, Fe, Ni and Pb). Although, this study does not directly establish a causal link between the specific contaminants detected at the study sites and differences in genetic diversity, our data are consistent with the hypothesis that pollution-induced selection has contributed in some fashion to the lower genetic diversity found at the urban sites.  相似文献   
916.
The U.S. Department of Energy is conducting a project to accelerate remediation through the use of monitored natural attenuation and enhanced attenuation for chlorinated ethenes in soils and groundwater. Better monitoring practices, improved scientific understanding, and an advanced regulatory framework are being sought through a team effort that engages technology developers from academia, private industry, and government laboratories; site cleanup managers; stakeholders; and federal and state regulators. The team works collaboratively toward the common goals of reducing risk, accelerating cleanup, reducing cost, and minimizing environmental disruption. Cutting‐edge scientific advances are being combined with experience and sound environmental engineering in a broadly integrated and comprehensive approach that exemplifies socalled “third‐generation R&D.” The project is potentially a model for other cleanup activities. © 2004 Wiley Periodicals, Inc.  相似文献   
917.
We synthesized nine studies that examined the influence of land use at different spatial scales in structuring biotic assemblages and stream channel characteristics in southeastern Minnesota streams. Recent studies have disagreed about the relative importance of catchment versus local characteristics in explaining variation in fish assemblages. Our synthesis indicates that both riparian- and catchment-scale land use explained significant variation in water quality, channel morphology, and fish distribution and density. Fish and macroinvertebrate assemblages can be positively affected by increasing the extent of perennial riparian and upland vegetation. Our synthesis is robust; more than 425 stream reaches were examined in an area that includes a portion of three ecoregions. Fishes ranged from coldwater to warmwater adapted. We suggest that efforts to rehabilitate stream system form and function over the long term should focus on increasing perennial vegetation in both riparian areas and uplands and on managing vegetation in large, contiguous blocks. Minnesota Cooperative Fish and Wildlife Research Unit is jointly sponsered by U.S. Geological Survey Biological Resources Division, the University of Minnesota, The Minnesota Department of Natural Resources, and the Wildlife Management Institute.  相似文献   
918.
Reviews     
Shadrach Woods, The Man in the Street, Harmondsworth, Penguin, 1975

W. Houghton Evans, Planning Cities, London, Lawrence & Wishart, 1975, £7

R. Taylor, M. Cox & I. Dickens eds., Britain's Planning Heritage, London, Croom Helm for The Royal Town Planning Institute, 1975. £5.75 (hardcover) £3.50 (paperback)

Development Plan Evaluation and Robustness: Application of an Analytical Programme and a Review of Measures of Performance, Department of the Environment Research Report 5 Local Government Operations Research Unit Report C217, 1976. Gratis.

J. Appleton, The Experience of Landscape, London, John Wiley, 1975

J. D. Hunt & P. Willis eds., The Genius of the Place: The English Landscape Garden 1620–1820, London, Paul Elek, 1976. £12.50

N. Pevsner, Staffordshire, Harmondsworth, Middx., Penguin Buildings of England Series, 1974, £3.50 (hardcover)

R. Bailey & M. Brake eds., Radical Social Work, London: Edward Arnold, 1975. £4.25 (hardcover) £1.95 (paperback)

and

The Use of Action Research in Developing Urban Planning Policy: Report of Colloquium, Bristol, June 1975 London, Department of the Environment, 1975.

M. Harloe, Swindon: A Town in Transition, London, Heinemann for the centre for Environmental Studies, 1975.

D. W. Pearce ed., The Economics of Natural Resource Depletion, London, Macmillan, 1975.

J. B. Goddard, Office Location in Urban and Regional Development

B. Fullerton, The Development of British Transport Networks

B. T. Robson, Urban Social Areas

P. L. Knox, Social Well‐Being: A Spatial Perspective

Four volumes in the Theory and Practice in Geography series, edited by J. W. House, A. S. Gouldie & J. H. C. Patten and published by Oxford University Press, 1975. All paperback at £0.90.

James A. Swan & William B. Stapp eds., Environmental Education: Strategies Toward a More Liveable Future, Halstead Press — John Wiley, 1974.

A. G. Wilson & M. J. Kirkby, Mathematics for Geographers and Planners, Oxford: Clarendon Press, 1975  相似文献   

919.
Synthesis and speciation of polyaluminum chloride for water treatment   总被引:1,自引:0,他引:1  
In this study, synthesis and speciation of polyaluminum chloride (PAC) for application in water treatment was investigated using a colorimetric speciation method. It was possible to produce stable preparations of PAC solutions in which a relatively stable cationic polymer predominated. The mode of preparation has a dramatic effect on the composition of PAC preparation. Some important parameters such as hydroxyl ligand number, mixing intensity, base injection rate and method, and aging were identified in this study.  相似文献   
920.
This article covers the strategic, organizational, and operational decisions involved in one automobile manufacturer's efforts to balance its goals of productivity and high quality with the more elusive goal of environmental responsibility. The case material is based on the real-life experiences of Honda of America's two manufacturing plants in East Liberty and Marysville, Ohio. The case unfolds as the environmental manager in charge of the two plants faces the pending visit of her corporate boss from Tokyo, who has made it clear that environmental issues are of growing importance in Honda's overall direction. ISO 14000, the new environmental quality standards being adopted by some other manufacturers, serves as a focusing issue for the environmental manager's thinking, but this issue is really representative of a wider challenge facing the Ohio plants: balancing Honda's core mission of producing the best cars at the lowest cost possible, and being a responsible actor in the environmental arena. Complicating this challenge, the environmental manager has to negotiate another tension common in global manufacturing firms today: balancing the influence of Honda's corporate headquarters in Japan with the local and regional context at its American plant sites.  相似文献   
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