全文获取类型
收费全文 | 8111篇 |
免费 | 296篇 |
国内免费 | 314篇 |
专业分类
安全科学 | 335篇 |
废物处理 | 117篇 |
环保管理 | 2407篇 |
综合类 | 2598篇 |
基础理论 | 865篇 |
环境理论 | 7篇 |
污染及防治 | 167篇 |
评价与监测 | 162篇 |
社会与环境 | 1831篇 |
灾害及防治 | 232篇 |
出版年
2024年 | 12篇 |
2023年 | 64篇 |
2022年 | 116篇 |
2021年 | 151篇 |
2020年 | 149篇 |
2019年 | 132篇 |
2018年 | 118篇 |
2017年 | 215篇 |
2016年 | 206篇 |
2015年 | 171篇 |
2014年 | 212篇 |
2013年 | 545篇 |
2012年 | 441篇 |
2011年 | 517篇 |
2010年 | 380篇 |
2009年 | 340篇 |
2008年 | 308篇 |
2007年 | 500篇 |
2006年 | 501篇 |
2005年 | 417篇 |
2004年 | 404篇 |
2003年 | 383篇 |
2002年 | 389篇 |
2001年 | 310篇 |
2000年 | 339篇 |
1999年 | 278篇 |
1998年 | 202篇 |
1997年 | 176篇 |
1996年 | 121篇 |
1995年 | 121篇 |
1994年 | 88篇 |
1993年 | 89篇 |
1992年 | 58篇 |
1991年 | 27篇 |
1990年 | 35篇 |
1989年 | 12篇 |
1988年 | 16篇 |
1987年 | 11篇 |
1986年 | 17篇 |
1983年 | 7篇 |
1982年 | 23篇 |
1981年 | 8篇 |
1980年 | 15篇 |
1979年 | 20篇 |
1978年 | 11篇 |
1977年 | 9篇 |
1975年 | 7篇 |
1974年 | 7篇 |
1973年 | 6篇 |
1971年 | 14篇 |
排序方式: 共有8721条查询结果,搜索用时 147 毫秒
301.
红外和热分析联用在化工产品研究中的应用 总被引:1,自引:0,他引:1
运用实例论述了红外光谱分析与热分析联用在化工产品的产品开发和检测方面的应用。 相似文献
302.
实施循环经济推动大型煤炭企业可持续发展 总被引:2,自引:0,他引:2
经济发展与环境保护之间的矛盾,一直是困扰国有大型煤炭企业发展的大问题,循环经济模式能够从根本上解决这一矛盾.本文以龙口矿业集团公司为例,论述了发展循环经济是实现煤炭企业可持续展的必由之路. 相似文献
303.
B. Y. Aminuddin M. H. Ghulam W. Y. Wan Abdullah M. Zulkefli R. B. Salama 《Water, Air, & Soil Pollution: Focus》2005,5(1-2):89-101
Cameron Highlands is a mountainous region with steep slopes. Gradients exceeding 20∘ are common. The climate is favourable to the cultivation of tea, sub-tropical vegetables and flowers (under rain-shelter).
Crop production is sustained by high fertiliser and manure applications. However, agriculture in this environment is characterised
by high levels of soil erosion and environmental pollution. A study on the sustainability of these agro-ecosystems was conducted.
Results indicated that soil loss was in the range of 24–42 ton/ha/yr under vegetables and 1.3 ton under rain-shelter. Sediment
load in the vegetable sub-catchment reached 3.5 g/L, 50 times higher than that associated with flowers under rain-shelter
and tea. The sediments contained high nutrient loads of up to 470 kg N/ha/yr. The N, P and K lost in runoff from cabbage farms
was 154 kg/season/ha, whereas in chrysanthemum farms it was 5 kg. In cabbage farms, the N, P, and K lost through leaching
was 193 kg/season/ha. The NO3–N concentration in the runoff from the cabbage farms reached 25 ppm but less than 10 ppm in runoff from rain-shelters. Inorganic
pollution in the rivers was within the acceptable limit of 10 ppm. The sustainability of the agro-ecosystems is in the order
of tea { > } rain–shelter ≫ vegetables. 相似文献
304.
从地域优势、农产品特征、生态条件等方面,论述了新疆发展有机食品生产的适宜性和重要意义.认为新疆发展有机食品生产可以利用得天独厚的气候、水土等自然资源,以及工业污染环境影响较小的有利条件,保护和改善农村生态环境,充分发挥独特的农产品资源优势,提高农产品附加值,变资源优势为经济优势,并结合新疆区情,从多方面提出了新疆发展有机食品的思路和措施. 相似文献
305.
306.
307.
宁阳县发展循环经济过程中所取得的初步成果,同时对当前存在的突出问题,提出了相应的对策和改进措施:制定促进循环经济发展的相关政策;构筑循环经济基本模式,推动建立生态工业园;建立循环经济发展的技术支撑体系;制定发展循环经济的长远规划;提高全民发展循环经济意识和公众参与水平. 相似文献
308.
The relationship between tourism development and vegetated landscapes is analyzed for the Luya Mountain Nature Reserve (LMNR),
Shanxi, China, in this study. Indices such as Sensitive Level (SL), Landscape Importance Value (LIV), information index of
biodiversity (H’), Shade-tolerant Species Proportion (SSP), and Tourism Influencing Index (TII) are used to characterize vegetated
landscapes, the impact of tourism, and their relationship. Their relationship is studied by Two-Way Indicator Species Analysis
(TWINSPAN) and Detrended Correspondence Analysis (DCA). TWINSPAN gives correct and rapid partition to the classification,
and DCA ordination shows the changing tendency of all vegetation types based on tourism development. These results reflect
the ecological relationship between tourism development and vegetated landscapes. In Luya Mountain Nature Reserve, most plant
communities are in good or medium condition, which shows that these vegetated landscapes can support more tourism. However,
the occurrence of the bad condition shows that there is a severe contradiction between tourism development and vegetated landscapes. 相似文献
309.
The development and effective introduction of strategies designed to ensure the ecologically and economically sustainable utilization of coastal and marine resources is perhaps the major challenge for Small Island Developing States (SIDS). In response, the 1994 Barbados Programme of Action (BPoA) called upon the SIDS to implement appropriate coastal and marine strategies and, crucially, ensure that such strategies were integrated into sustainable national development plans (NDPs). This article examines the extent to which contemporary NDPs and donor support programmes have incorporated the fisheries sector — arguably the most important coastal/marine resource for many SIDS — into such documents. Applying an assessment methodology, originally developed to identify levels of environmental mainstreaming within World Bank country assistance strategies to NDPs and donor support programmes, we are able to identify those SIDS who have most effectively integrated the fisheries sector into such documents. Comparison with data indicating the importance of the sector to the national economy (in terms of generating foreign exchange, employment generation and/or supporting domestic protein consumption levels) enables us to pinpoint those countries with substantial fisheries sectors, but a correspondingly lower than expected degree of sectoral mainstreaming. We suggest that the January 2005 review of the BPoA offers an opportune moment for such countries to redress these omissions. 相似文献
310.
Dalia Streimikiene 《Natural resources forum》2005,29(4):322-333
This article summarizes some of the results from the application of the indicators for sustainable energy development (ISED) tool for analyzing Lithuania's energy sector, in terms of trends, setting energy policy goals and monitoring progress towards these goals. This experience illustrates the potential applicability of the ISED methodology for energy policy development in economies in transition, using Lithuania as an example. The article presents a summary of the results achieved and conclusions arrived at from the analysis of six priority areas in the context of the research project coordinated by the International Atomic Energy Agency, and provides recommendations for the development of sustainable energy policy using the ISED approach. 相似文献