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701.
可降解塑料研究现状与发展前景   总被引:4,自引:0,他引:4  
可降解塑料是近年来随着环保呼声的日渐增强而发展起来的新研究热点,主要介绍可降解塑料的种类及其推广中存在的问题,并对前景作了展望。  相似文献   
702.
The adoption of environmentally sustainable techniques by cooperatives and small companies results in specific difficulties rarely discussed in the literature. This paper describes an action-research carried out by seafood cultivators and university researchers in Guanabara Bay, which resulted in the substitution of the previous technique, based on extraction, by one without negative environmental impacts. The economic results have been satisfactory, so it can be expected that this activity may become more widespread in the region.  相似文献   
703.
试验本着农村产业结构调整,退耕还草畜养和绿洲生态农业优化管理的研究宗旨,把甜高粱作为南疆农村产业结构调整和发展生态畜牧业的优良品种在尉犁县进行栽培试验.结果表明在南疆类似尉犁县气候条件的地区,其生育期为130d,每年除收获种子外还可收割一茬牧草,年产鲜草86 400 kg/hm2、收获种子1 770 kg/hm2.  相似文献   
704.
Occupational Health and Safety in Spain has improved considerably over the last decade, most likely due to a new concept where an overall concept of safety culture is defined. Important changes in industrial safety, hygiene, and psychosocial factors present an optimistic panorama for the future of Spain. Despite this general improvement, according to the European Convergence Program, Spanish statistics still offer far from good safety results. In fact, according to 1997 official statistics, Spain had the highest incidence rate for nonfatal occupational accidents of all European Union (EU) countries, and occupied third place for fatal accidents. This paper summarizes the organizational structure of the Spanish National System of Health & Safety at Work, its effective health and safety laws, and statistics on the Spanish work environment obtained from III Spanish National Survey on Work Conditions (1997). The researchers hope that the findings of this work will have an impact on Spanish industry that will subsequently bring about improvements in work conditions and develop assessment and intervention models in occupational health and safety, from a theoretical position integrating environmental, human, and organizational factors.  相似文献   
705.
中国海滨旅游研究进展   总被引:2,自引:0,他引:2  
在阅读大量相关文献资料的基础上,试图从海滨旅游兴起的原因、海滨旅游主体、海滨旅游客体及海滨旅游主客体间关系4个方面对近年来国内有关海滨旅游的研究作一系统综述.在此基础上,对中国海滨旅游以后的研究进行了展望.  相似文献   
706.
饮用水中半挥发性有机物的GC/MS分析方法研究   总被引:1,自引:0,他引:1  
介绍用毛细管气相色谱/质谱联用技术(GC/MS)对饮用水中半挥发性有机物的分析研究。饮用水经吸附富集、洗脱、浓缩后,用GC/MS测定,定性检出50种半挥发性有机物,并对19种主要的半挥发性有机污染物进行定量分析。  相似文献   
707.
ABSTRACT: Recent developments in multiple objective decision making methods presented in the upcoming sequence of research papers are evaluated and compared with respect to their usefulness in addressing challenging problems in water resources management. Because many of the decision making techniques originated in the field of operational research, the historical evolution of this field is outlined and the current need for developing a wide range of techniques for employment in strategic decision making is pointed out. Informative attributes for classifying decision making techniques are given to allow a practitioner to select decision aids that can best model the key characteristics of the particular problems under study. By systematically applying a wide variety of multiple objective decision making techniques to many different kinds of water resources problems, the authors of the papers clearly demonstrate the effectiveness of utilizing these methods for assisting in making both tactical and strategic decisions in water resources management.  相似文献   
708.
ABSTRACT: The growing problem of nonpoint source ground water contamination from agricultural chemicals is conceptualized as an historical outcome of the production environment of capitalist agriculture in the Corn Belt. Chronic overproduction and ground water contamination reveal different aspects of the same technological treadmill. The debate over Iowa's 1987 Ground Water Protection Act symbolizes the contradiction between popular demand for clean water and structural limits on policymaking. Although the Act does provide for expanded research, education, and monitoring, a coalition of commercial farmers, local chemical dealers, and the national chemical industry defeated a tax on pesticide use. Analysis of alternate policy responses - Best Management Practices (BMPs), cross compliance, site-specific regulation of chemical use, and taxation of synthetic chemicals - reveals that all tend to founder on the same structural constraints. Without practical, profitable, low-input technologies that farmers, over time, would choose to adopt, both voluntary and regulatory approaches encounter major political or implementation difficulties. The public agricultural research agenda, therefore, emerges as a central control variable for ground water quality management and a central focus for political struggle.  相似文献   
709.
ABSTRACT: Managers of water related outdoor recreation resources want to provide facilities and recreational opportunities of high quality that are attractive to recreationists. The reported research develops a relevant site quality assessment and measurement procedure called environmental threshold modeling. This modeling procedure is based upon the idea that individuals (i.e., recreationists) have specific, identifiable evaluative criteria which can be expressed as a mathematical function of various site characteristics. The function of interest is called a threshold function because it separates acceptable recreational settings from unacceptable settings. Individual specific threshold functions can be easily aggregated to form a population specific threshold function that estimates the proportion of a population that would find the recreational setting acceptable for some specific activity. Presented in this paper are illustrative calibration results based upon survey data collected from recreational canoeists using the Pine River in Michigan's Manistee National Forest.  相似文献   
710.
ABSTRACT: The psychosocial impact of a large water impoundment project upon members of a small farming community located within central Ohio was evaluated using a study-restudy research design. Attitudes toward selected community variables were examined during the initial stages of land acquisition and reevaluated four years later at the completion of the project. The findings revealed that fragmentation of the “social fabric” of the community did not occur. Several statistically significant differences were observed between the two data sets but the findings indicated that community residents held more positive attitudes toward their community following the development action than at the beginning of the project.  相似文献   
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