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911.
912.
Environmental Impact Evaluation Model for Industrial Processes 总被引:4,自引:0,他引:4
This paper proposes a model to evaluate the environmental impact of manufacturing processes. This model uses the potency factor approach to classify environmental impacts into five ecological health impact groups and uses their toxicological, cancer, and physical effects as the bases to rate the seven groups of human health impacts. The environmental impacts in each impact group are reported, and their hazard scores on ecological and human health are determined. The model also generates a single score for the overall environmental impacts of a process. This single score system helps to identify, among all the viable processes, which is the most environmentally friendly process. This model can serve as a tool to highlight the potential environmental hazards of process operations and to provide information about environmental performance for decision making. The model has been developed into a computer software program, Environmental Impact Evaluation System, and is demonstrated by using the processes employed for the manufacture of paper bags. 相似文献
913.
914.
915.
高效液相色谱和离子色谱在形态分析中的应用 总被引:2,自引:0,他引:2
本文综述了高效液相色谱(HPLC)和离子色谱(IC)在形态分析方面的应用,包含:元素的价态分析、有机金属化合物的形态确定、元素存在状态确定、对映体化合物的分离与鉴定。附参考文献133篇。 相似文献
916.
W. Joseph Martin Edward L. Thackston 《Journal of the American Water Resources Association》1980,16(6):1006-1011
ABSTRACT: A retrospective benefit-cost analysis of major water resources projects in the Cumberland River basin was conducted. The U.S. Army Corps of Engineers' projects selected were Dale Hollow, Wolf Creek, Center Hill, and J. Percy Priest Reservoirs. The ex-post performance of the evaluated reservoirs were compared to the ex-ante estimates. Benefits and costs for each project were deflated to their base year and respective average annual values for each of these components were calculated. An ex-post benefit-cost ratio was determined for each project, as well as the combined system. The benefit-cost ratio for each project surpassed unity. The actual ratio as compared to the ex-ante estimate for each project is as follows: Dale Hollow, 1.24 to 1.46; Wolf Creek, 1.40 to 1.53; Center Hill, 1.17 to 2.02; and J. Percy Priest, 1.45 to 1.6. The internal rate of return was also determined for each project. The results obtained for each project are tabulated and discussed with consideration given to factors effecting the economic evaluation of the projects. 相似文献
917.
ABSTRACTThe long-standing debate on environmental policy ‘leaders’ and ‘laggards’ lends itself to a new analysis following with the advent of the 2008 economic crisis. This paper, therefore, asks the question to what extent do European Union (EU) member states have the capacity and willingness to implement EU environmental policy amid austerity, budget cuts, and rising costs over the period 2008–2014. Building upon previous studies, 26 interviews with European, Greek and United Kingdom participants and records of environmental infringements, the paper provides a contemporary picture of the environmental policy ‘leader-laggard’ dynamic in Europe. The findings demonstrate that the impact of the economic crisis seems contestable and varies amongst member states, while the reduction in environmental infringements appears to have a link with the decrease in economic activity. Although environmental policy ‘leaders’ maintain patterns of strong implementation, the improved implementation performance of some ‘laggards’ reflects a shift in their implementation patterns amid a period of intense political and economic controversies. 相似文献
918.
在对全地面多轴汽车起重机进行结构分析和受力分析的前提下,着重研究了多轴汽车起重机整机、制动系统及各组成部分对整车制动安全性能的影响,并以QYU160 为例,对整车制动安全性能进行了分析计算和试验研究,两者结果相吻合。 相似文献
919.
Blocksom KA 《Environmental management》2003,31(5):0670-0682
When biological metrics are combined into a multimetric index for bioassessment purposes, individual metrics must be scored
as unitless numbers to be combined into a single index value. Among different multimetric indices, methods of scoring metrics
may vary widely in the type of scaling used and the way in which metric expectations are established. These differences among
scoring methods may influence the performance characteristics of the final index that is created by summing individual metric
scores. The Macroinvertebrate Biotic Integrity Index (MBII), a multimetric index, was developed previously for first through
third order streams in the Mid-Atlantic highlands of the United States. In this study, six metric scoring methods were evaluated
for the MBII using measures related to site condition and index variability, including the degree of overlap between impaired
and reference distributions, relationships to a stressor gradient, within-sample index variability, temporal variability,
and the minimum detectable difference. Measures of index variability were affected to a greater degree than those of index
responsiveness by both the type of scaling (discrete or continuous) and the method of setting expectations. A scoring method
using continuous scaling and setting metric expectations using the 95th percentile of the entire distribution of sites performed
the best overall for the MBII. These results showed that the method of scoring metrics affects the properties of the final
index, particularly variability, and should be examined in developing a multimetric index because these properties can affect
the number of condition classes (e.g., unimpaired, impaired) an index can distinguish. 相似文献
920.
Age differences in safety attitudes and safety performance in Hong Kong construction workers 总被引:1,自引:0,他引:1
PROBLEM: Safety in the construction industry is a major issue in Hong Kong, representing about 46% of all occupational injuries in 1998. This study explored linear and curvilinear relations between age and safety performance (accident rates and occupational injuries), as well as safety attitudes, in construction workers in Hong Kong. METHOD: A Chinese version of the Safety Attitude Questionnaire (SAQ by Donald & Canter) was developed and administered to a sample of Chinese construction workers (N=374, 366 males, 8 females) from 27 construction sites. RESULTS: Accident rates were not related to age. Occupational injuries were related to age in a curvilinear manner, with injuries at first increasing with age, then decreasing. Two safety attitude scales were related to age with older workers exhibiting more positive attitudes to safety. If age and tenure are controlled, some attitude scales are predictors of safety performance. IMPACT ON INDUSTRY: Management/supervisors, team leaders, and workers are all responsible for safety, and any negative bias toward older construction workers is unfounded. 相似文献