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101.
锡林郭勒盟煤炭资源丰富,探明储量1448亿吨,仅次于鄂尔多斯市居全区第二。大规模资源开发引起地貌、土壤、植被、水文、空气质量的环境构成要素的破坏,正在以扬沙、空气污染等方式反作用于人类。加强矿山环境保护势在必行,只要我们坚持开发、保护和治理相结合,认真处理矿产资源开发与经济发展、生态环境保护三者之间关系,矿山生态环境就会大大改善,科学发展观也就会真正落到实处。  相似文献   
102.
Coordinated voluntary approaches to Pollution Prevention are widely practiced in many western-style economies. However, little empirical research has been undertaken into the extent to which these approaches match best practice pollution prevention approaches. In this paper nine programs employed by five regional and district councils in New Zealand are evaluated against nine ‘Best Practice’ design features. All five councils’ pollution prevention programs contained some of the best practice design features in their program’s design. Perhaps not surprisingly the older programs rank highest out of the five. However, all programs have the potential to develop towards containing all of the ‘best practice’ design features, with most emphasis needed on the credibility of program monitoring. From an ongoing research perspective, and also from an overall PP program performance point of view, the biggest challenge remains the extent and depth that the programs apply each of the design features. As presented they are extremely generic. While generic design features provide for flexibility in implementation, often seen as a positive, they can also be a recipe for ‘tokenism’, something that future researchers and program managers need to be aware of. We also sought to determine if these programs were contributing to sustainable management in New Zealand. Findings in this respect were equivocal. This finding in part is due to the lack of specificity around targets, monitoring and reporting, items needing further attention from managers and researchers.  相似文献   
103.
Voluntary approaches to industry-wide pollution prevention programs have gained a global impetus. Despite this impetus relatively little research has been undertaken into identifying key features of successful programs. This research identified these features by reviewing selected programs in five countries, Australia, Canada, Japan, the United Kingdom and the United States. Nine key features have been identified, namely: Adequate and consistent funding; Collaborative relationship with industry; Single sector program focus; Setting credible goals; Info-regulation and resources available; Threat of credible enforcement; Regular and credible monitoring; Visible participant benefits; and, Transparent provision of program results. The research complements other work and while showing a high level of similarity in the features, provided also for the inclusion of two further design features, namely ‘adequate and consistent funding’, and developing a maintaining a ‘collaborative relationship with industry’. It is suggested that the nine design features alone, while important, are insufficient and that further research is required to identify these other supporting factors.  相似文献   
104.
基于关联维的事故时间序列分形特征分析   总被引:4,自引:3,他引:1  
根据我国"十五"期间事故统计数据,构造了一个事故时间序列;基于相空间重构理论,对事故序列进行了相空间重构,应用G-P算法,对事故时间序列的分形特征进行了研究,计算得出事故时间序列的关联维数。研究结果表明:当嵌入维数达到8以后,该事故动力学系统具有稳定的关联维数4.7,说明至少有5个因子在影响着事故时间序列的动态变化,并且该系统的有效自由度为8。本研究对建立事故时间序列的预测模型有较大的参考价值。  相似文献   
105.
An investigation of gaseous elemental mercury concentration in atmosphere was conducted at Beijing and Guangzhou urban, Yangtze Delta regional sites and China Global Atmosphere Watch Baseline Observatory (CGAWBO) in Mt. Waliguan of remote continental area of China. High temporal resolved data were obtained using automated mercury analyzer RA-915 . Results showed that the overall hourly mean Hg0 concentrations in Mt. Waliguan were 1.7± 1.1 ng/m3 in summer and 0.6±0.08 ng/m3 in winter. The concentration in Yangtze Delta regional site was 5.4±4.1 ng/m3, which was much higher than those in Waliguan continental background area and also higher than that found in North America and Europe rural areas. In Beijing urban area the overall hourly mean Hg0 concentrations were 8.3±3.6 ng/m3 in winter, 6.5±5.2 ng/m3 in spring, 4.9±3.3 ng/m3 in summer, and 6.7±3.5 ng/m3 in autumn, respectively, and the concentration was 13.5±7.1 ng/m3 in Guangzhou site. The mean concentration reached the lowest value at 14:00 and the highest at 02:00 or 20:00 in all monitoring campaigns in Beijing and Guangzhou urban areas, which contrasted with the results measured in Yangtze Delta regional site and Mt. Waliguan. The features of concentration and diurnal variation of Hg0 in Beijing and Guangzhou implied the importance of local anthropogenic sources in contributing to the high Hg0 concentration in urban areas of China. Contrary seasonal variation patterns of Hg0 concentration were found between urban and remote sites. In Beijing the highest Hg0concentration was in winter and the lowest in summer, while in Mt. Waliguan the Hg0 concentration in summer was higher than that in winter. These indicated that different processes and factors controlled Hg0 concentration in urban, regional and remote areas.  相似文献   
106.
我国水灾的基本特征及成因分析   总被引:1,自引:0,他引:1  
本文研究了我国水灾的基本特征,分析了水灾形成的主要原因,提出了防御洪灾的措施。  相似文献   
107.
作为科研成果的信息载体,科技期刊有着重要的作用。而处于整个出版工作的中心环节的编辑更应在求新、求快的基础上,坚持求准的原则,不断学习,才能将科技期刊越办越好。  相似文献   
108.
网络教学能很好地把信息技术和数学教学有机的整合。本文介绍了网络环境下数学课堂七步教学模式(1)明确目标(2)创设情境(3)自主探索(4)网上协作(5)师生交流(6)在线反馈(7)课题延伸;并介绍了其特征:(1)自主性(2)和谐性(3)变化性(4)创造性(5)协作性。  相似文献   
109.
杨鸿亮 《云南环境科学》2000,19(1):51-51,58
本文对保山市城市垃圾物相组成及其发热量等性质进行了研究 ,对城市垃圾的有效利用和处理提供了技术支持 ,并提出了适合其特性的处理方式  相似文献   
110.
The endangered species Melica virgata was studied with respect to geographic distribution, the recent state of cenopopulations, the characteristics of habitats, phytocenotic relationships, morphology, and specific ecological and physiological features. The data on the introduction, biochemical composition, and economic significance of M. virgata are presented, and measures aimed at species conservation are proposed.  相似文献   
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