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271.
This paper summarizes information on the spatial and temporal variability of selected air toxics pollutants collected on a national basis primarily for a period encompassing 1990-2003. Spatial information on pollutant concentrations is characterized in terms of within-city and between-city variability. Temporal information is summarized as diurnal and seasonal variability and in multiyear trends. The information on variability is presented in the framework of a larger need for systematic documentation of information on air toxics pollutants to assess progress in air pollution control programs.  相似文献   
272.
U.S. Environmental Protection Agency (EPA) Emission Measurement Center in conjunction with EPA Regions VI and VIII, the state of Utah, and the U.S. Department of Defense have conducted a series of long-term pilot and field tests to determine the accuracy and reliability of a visible opacity monitoring system consisting of a conventional digital camera and a separate computer software application for plume opacity determination. This technology, known as the Digital Opacity Compliance System (DOCS), has been successfully demonstrated at EPA-sponsored Method-9 "smoke schools", as well as at a number of government and commercially operated industrial facilities. Results from the current DOCS regulatory pilot study demonstrated that, under regulatory enforcement conditions, the average difference in opacity measurement between the DOCS technology and EPA Reference Method 9 (Method 9) was 1.12%. This opacity difference, which was computed from the evaluation of 241 regulated air sources, was found to be statistically significant at the 99% confidence level. In evaluating only those sources for which a nonzero visible opacity level was recorded, the  相似文献   
273.
The first nuclear explosion test, named the Trinity test, was conducted on July 16, 1945 near Alamogordo, New Mexico. In the tremendous heat of the explosion, the radioactive debris fused with the local soil into a glassy material named Trinitite. Selected Trinitite samples from ground zero (GZ) of the test site were investigated in detail for radioactivity. The techniques used included alpha spectrometry, high-efficiency gamma-ray spectrometry, and low-background beta counting, following the radiochemistry for selected radionuclides. Specific activities were determined for fission products (90Sr, 137Cs), activation products (60Co, 133Ba, 152Eu, 154Eu, 238Pu, 241Pu), and the remnants of the nuclear fuel (239Pu, 240Pu). Additionally, specific activities of three natural radionuclides (40K, 232Th, 238U) and their progeny were measured. The determined specific activities of radionuclides and their relationships are interpreted in the context of the fission process, chemical behavior of the elements, as well as the nuclear explosion phenomenology.  相似文献   
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Suppliers' development is a critical function within supply chain management. Green supplier development is also necessary for effective green supply chain management. Interestingly, there is a gap in the research on how an organization can effectively manage supplier development programs, and specifically green supplier development. The use of formal models to aid green supplier development management is virtually non-existent. This paper aims to fill this gap by introducing a formal model using rough set theory to investigate the relationships between organizational attributes, supplier development program involvement attributes, and performance outcomes. The performance outcomes focus on environmental and business dimensions. The rough set methodology utilizes an ‘incomplete’ information approach which is more realistic in some data poor environments. A multistage rough set methodology is detailed through an illustrative application. The methodology generates decision rules relating the various attributes to the performance outcomes. Included in the discussion are insights into how these rules for individual and aggregated performance (environmental, business, and joint performance) may be evaluated. Practical and research implications of this work are detailed in the paper.  相似文献   
277.
Data from the International Social Survey Programme 2000 and 2010 environment modules were analyzed to explore the relationships between attitudes, behavior, and sociodemographic variables to citizens’ preferences to aspects of environmental discourse in the Philippines. Overall, significantly more people agree to multilateralism, equity, and the link between the environment and economic progress in 2010 as compared to 2000. A series of multinomial logistic regressions were conducted to determine significant predictors to peoples’ disposition to variables related to three overarching environmental discourses. After controlling for other covariates, the study found that the more the Filipinos adhere to statements toward science and nature that are negatively connoted: the more likely they are to agree to international multilateral commitments and ascribe to equity for poorer countries in environmental efforts; and less likely to disagree to the aspects of multilateralism, equity, and the link between the environment and economic progress. Furthermore, the results showed that demographics and civic participations generally did not have a statistically significant impact on Filipino’s agreement or disagreement to environmental discourses. The paper then discusses the implications of the findings and conclusions of the study.  相似文献   
278.
ABSTRACT: The relation between landscape characteristics and water chemistry on the Delmarva Peninsula can be determined through a principal-component analysis of basin characteristics. Two basin types were defined by factor scores: (1) well-drained basins, characterized by combinations of a low percentage of forest cover, a low percentage of poorly drained soil, and elevated channel slope; and (2) poorly drained basins, characterized by a combinations of an elevated percentage of forest cover, an elevated percentage of poorly drained soil, and low channel slopes. Results from base-flow sampling of 29 basins during spring 1991 indicate that water chemistry of the two basin types differ significantly. Concentrations of calcium, magnesium, potassium, alkalinity, chloride, and nitrate are elevated in well-drained basins, and specific conductance is elevated. Concentrations of aluminum, dissolved organic carbon, sodium, and silica are elevated in poorly drained basins whereas specific conductance is low. The chemical patterns found in well-drained basins can be attributed to the application of agricultural chemicals, and those in poorly drained basins can be attributed to ground-water flowpaths. These results indicate that basin types determined by a quantitative analysis of basin characteristics can be related statistically to differences in base-flow chemistry, and that the observed statistical differences can be related to major processes that affect water chemistry.  相似文献   
279.
This article describes and tests a systems theory-based policy indicators model. The framework is used to examine propositions about linkages between states' ecological-spatial characteristics and subsequent selected solid waste management (SWM) -related environmental policies. It was hypothesized that state characteristics of: (1) population density (used as a garbage-per-land area index), (2) population convergence within urban areas, and (3) percent population change in the interval 1980–1985, could jointly explain state variation in both the number and the vigor of SWM policy outputs. Greater levels of spatial pressure were proposed to be related directly to more numerous, more convincing policies. Proposals are grounded in the literature of organizational search theory, crisis stimulation, and technological pressure. Results revealed that the sociospatial model in fact could explain a reasonable proportion of policy variation across states. However, not all hypotheses are supported. Population change shows an indirect, rather than the anticipated direct, relationship with policy output levels. In addition, when used in the model as a pollution intensity index, population density failed to contribute significantly to an explanation of differences in state SWM policy levels. The analysis raises questions about changes occurring over time in the nature and direction of linkages between sociospatial measures and policy responses. This study suggests that strengthening policy indicator models may require questioning key assumptions and theoretical bases, conducting longitudinal studies, and factoring in political, economic, and other policy environment forces.  相似文献   
280.
Hyde Tools, Inc., of Southbridge, Massachusetts, is a medium-sized firm employing about three hundred persons. In 1988, it learned of a company that eliminated its wastewater discharge after being threatened with massive Clean Water Act fines resulting from a suit brought by a Massachusetts environmental group. Hyde decided to devise a similar program to attain zero water discharge and do it within five years. More than 75 percent toward its goal, Hyde'S environmental success, detailed in this article, still relies heavily on the company'S Total Quality Management system and the efforts of a dedicated environmental staff. Hyde'S success typifies TQEM in action—showing how small continuous improvements can lead to significant financial paybacks.  相似文献   
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