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931.
环境生物样品预处理中的微波溶样技术 总被引:2,自引:1,他引:2
微波溶样是近年产生的一种崭新的有前途的样品预处理技术,本文评述这一技术在环境、生物样品消解方面的近期应用。 相似文献
932.
933.
Morris L. Maslia Mustafa M. Aral Robert C. Williams Allan S. Susten Janet L. Heitgerd 《Journal of the American Water Resources Association》1994,30(6):1025-1041
ABSTRACT: Simulation of ground-water flow and fate of contaminants in the subsurface environment constitutes a major phase of most environmental assessment and site remediation studies. These simulation studies yield information on spatial and temporal distributions of contaminants in the subsurface media. An important use of this information is to conduct exposure assessment studies. Spatial and temporal distributions of both chemical concentrations and exposed populations render this integrated exposure analysis task rather difficult. Geographic Information Systems (GIS), on the other hand, provide a platform in which layered, spatially distributed databases can be manipulated with ease, thereby simplifying exposure analysis tasks significantly. In this paper, we describe procedures that combine the simulation models and demographic databases under a GIS platform to automate the exposure assessment phase of a typical health assessment study. Procedures developed herein significantly simplify the post-processing phase of the analysis, and render the overall task more ‘user friendly.’ A site-specific application is included as a demonstration of the proposed process. 相似文献
934.
Malcolm J. R. Clark Paul H. Whitfield 《Journal of the American Water Resources Association》1994,30(6):1063-1079
ABSTRACT: Current conventions for reporting analytical results from environmental samples brings the objectives of laboratory scientists into conflict with those of environmental scientists. The objective of chemical analyses is to provide estimates of the true composition of samples. Reported results must reflect the analytical uncertainty. Current conventions require left-censoring of those results below the Limit of Detection. The objective of statistical interpretation of environmental data is to provide estimates of the characteristics of ecosystems. Such statistical analyses are often confounded by left-censoring of analytical results. We review the different points of view and propose a compromise which recognizes these conflicting perspectives. 相似文献
935.
Teresa N. Malafi Marlene A. Devine Larry L. Lesher 《Journal of Polymers and the Environment》1994,2(4):219-223
This paper summarizes a study evaluating the acceptance and perceived performance of disposable cutlery made from starch-based biodegradable resins relative to nondegradable polystyrene cutlery. Two hundred forty-three sailors onboard three U.S. Navy vessels ate their lunch using either biodegradable cutlery made with resins manufactured by one of two commercial companies or polystyrene cutlery. The cutlery was rated on several sensory and performance dimensions as well as for overall acceptability. Results indicated that sailors rated both the biodegradable and the polystyrene utensils as easy to hold. There were also no differences in the perceived ease of using each of the spoons. However, compared to the polystyrene utensils, both types of biodegradable utensils were viewed as less sturdy, as having a less attractive color, and as being less acceptable overall. The biodegradable forks and knives were also rated as more difficult to use for piercing and cutting food than the polystyrene ones. In addition, several significant differences emerged between the two types of biodegradable cutlery. The results are discussed in terms of the need for continued consumer testing of products developed from biodegradable polymeric materials. 相似文献
936.
Dr. Hana L. Ayala 《Environmental management》1987,11(2):141-147
We are witnessing a growing concern with the global dimension of many environmental issues, reflected in the increase in the number and significance of international environmental organizations. Yet there is no internationally applicable strategy for environmental research which is management oriented. A new type of research policy, which integrates ideas derived from environmental and human ecology, is required in order to deal with cultural and ecological diversity and their interactions as reflected in the ecology of landscapes. The newly defined concept of environmental health is proposed to fill this gap. This concept integrates the latest developments in landscape evolutionary ecology and environmental health, bringing out a conflict between making the environment conducive to human health and increasing the available options for supporting the essential biological and ecological processes of the environment. Lessons derived from the evolution of human environments are used in order to illustrate how health may become un umbrella for developing an environmental research policy, which could also serve as a catalyst for international environmental projects. 相似文献
937.
The design and integration of models projecting the effects of management on environmental systems is one step in the environmental planning process. Interactions between resources produced on the same unit of land under current and future management can be examined only when assumptions and processes of these dynamic environmental systems are quantified. Multiresource interaction models have generally been large and cumbersome while also suffering from an inadequate amount of detail. This article presents a conceptual framework for integrating individual resource models to project multiresource interactions at a regional scale. Land management impact projections require common definitions of the total land base and common definitions of management activities applied to the same land unit. A case example focusing on the resources of timber, forage, wildlife, fish, and water for the southern United States is presented. 相似文献
938.
E. Ann Clark 《Journal of Agricultural and Environmental Ethics》1988,1(4):275-289
Changes in global patterns of grain production have affected the profitability of commercial, cash-crop agriculture in North America. The current financial crisis has highlighted a perceived conflict between the priorities of (1) strengthening net farm profit, (2) maintaining the productive potential of the land base, (3) enhancing the health and cohesiveness of the agricultural community, and (4) addressing societal demands for safe foodstuffs. Reducing input costs by reducing the need for privately owned machinery can minimize the scale-dependence of agricultural practices, as illustrated with examples involving silage and intensively managed pasture in Ontario. This approach could improve farming opportunities for nontraditional, part-time farmers, and at the same time, create a niche for professional custom operators and managers. Enhancing the viability of nontraditional farm operations, a historically neglected component of the farming community, as well as commercial farms is viewed as one approach to sustaining and improving both the agricultural land base and the agricultural community. Applying resource-extensive rather than resource-intensive approaches to forage management reveals that these apparently divergent priorities are, in fact, interlocking pieces of the same puzzle. 相似文献
939.
论区域环境规划与区域开发环境影响评价在区域开发环境管理中的作用和地位 总被引:3,自引:0,他引:3
回顾了国内外区域开发环境管理的发展历程,简要论述了区域环境规划与区域开发环境影响评价在区域开发环境管理中的作用和地位以及两者的相互关系。 相似文献
940.
五氯酚对环境污染及居民健康影响研究 总被引:2,自引:0,他引:2
中国长期以来使用五氯酚纳盐杀灭亡血吸虫的中间宿主──—钉螺.为评价它对环境的污染及居民健康危害,1990-1993年在我省开展了五氯酚环境污染及对居民健康影响研究.在研究区采集环境样品(空气、水体、土壤及底泥、蔬菜、肉、蛋、鱼等)共173份;生物材料(人血、尿)共457份,分析五氯酚浓度.结果在明,在五氯酚使用区,环境中PCP浓度稍高于对照区,而生物材料尿、血中PCP浓度明显高于对照区.全血胆碱脂酶活性用药区明显低于对照区,统计学分析有显著差异(P<0.001),证实了长期低剂量使用可造成环境及生物蓄积. 相似文献