全文获取类型
收费全文 | 41648篇 |
免费 | 434篇 |
国内免费 | 356篇 |
专业分类
安全科学 | 1219篇 |
废物处理 | 1582篇 |
环保管理 | 5823篇 |
综合类 | 6256篇 |
基础理论 | 11713篇 |
环境理论 | 24篇 |
污染及防治 | 11198篇 |
评价与监测 | 2537篇 |
社会与环境 | 1795篇 |
灾害及防治 | 291篇 |
出版年
2022年 | 268篇 |
2021年 | 300篇 |
2020年 | 230篇 |
2019年 | 321篇 |
2018年 | 563篇 |
2017年 | 554篇 |
2016年 | 832篇 |
2015年 | 710篇 |
2014年 | 1045篇 |
2013年 | 3288篇 |
2012年 | 1246篇 |
2011年 | 1780篇 |
2010年 | 1450篇 |
2009年 | 1511篇 |
2008年 | 1812篇 |
2007年 | 1920篇 |
2006年 | 1692篇 |
2005年 | 1417篇 |
2004年 | 1416篇 |
2003年 | 1339篇 |
2002年 | 1341篇 |
2001年 | 1677篇 |
2000年 | 1196篇 |
1999年 | 737篇 |
1998年 | 576篇 |
1997年 | 576篇 |
1996年 | 614篇 |
1995年 | 659篇 |
1994年 | 603篇 |
1993年 | 547篇 |
1992年 | 527篇 |
1991年 | 505篇 |
1990年 | 506篇 |
1989年 | 534篇 |
1988年 | 464篇 |
1987年 | 419篇 |
1986年 | 371篇 |
1985年 | 401篇 |
1984年 | 393篇 |
1983年 | 429篇 |
1982年 | 438篇 |
1981年 | 391篇 |
1980年 | 332篇 |
1979年 | 371篇 |
1978年 | 301篇 |
1977年 | 254篇 |
1976年 | 257篇 |
1975年 | 254篇 |
1973年 | 238篇 |
1972年 | 273篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
321.
322.
Athar Habib-ur-Rehman Ambreen Sarah Javed Muhammad Hina Mehwish Rasul Sumaira Zafar Zafar Ullah Manzoor Hamid Ogbaga Chukwuma C. Afzal Muhammad Al-Qurainy Fahad Ashraf Muhammad 《Environmental science and pollution research international》2016,23(18):18320-18331
Environmental Science and Pollution Research - Maize tolerance potential to oil pollution was assessed by growing Zea mays in soil contaminated with varying levels of crude oil (0, 2.5 and... 相似文献
323.
Scholz C. Jones T. G. West M. Ehbair A. M. S. Dunn C. Freeman C. 《Environmental science and pollution research international》2016,23(18):18192-18199
Environmental Science and Pollution Research - The objective of this study was to monitor a newly constructed wetland (CW) in north Wales, UK, to assess whether it contributes to an improvement in... 相似文献
324.
Bimal Kumar Mawandiya J. K. Jha Jitesh Thakkar 《International Journal of Sustainable Engineering》2016,9(5):315-328
This paper considers a two-echelon closed-loop supply chain consisting of a manufacturer and a remanufacturer at the upper echelon and a retailer at the lower echelon. The retailer faces a constant demand from customers, which is satisfied through recovered and new products received from the remanufacturer and the manufacturer, respectively. The manufacturer produces the product with finite rate, whereas the recovery of returned product is instantaneous at the remanufacturer. We develop three models to determine the optimal production-inventory policy of the players for minimizing the joint total cost of the system. In the first model, the retailer receives the product in batches from the manufacturer and the remanufacture simultaneously, whereas in the second and third models, the batches are received alternatively. In the third model, however, the procurement of raw material at the manufacturer is also considered. Numerical illustration is presented to examine the impact of certain key parameters. 相似文献
325.
S. Alvandi W. Li M. Schönemann C. Herrmann 《International Journal of Sustainable Engineering》2016,9(6):354-362
Value stream mapping (VSM) is a well-accepted tool within lean manufacturing concept which is often used for analysing and designing the flow of materials and information required to manufacture a product. However, the analysis is static and single product oriented, which fails to cope with either the variation of production plan or a multi-product environment. In addition, the environmental impact of a manufacturing system is highly associated with the dynamic consumption of energy and resources. Despite the recent integration of VSM with simulation or environmental studies (in the domain of energy efficiency), still neglected is the dynamic assessment of all the resources involved in a multi-product production environment. This paper presents a methodology for modelling multi-product manufacturing systems with dynamic material, energy and information flows with the aim to generate economic and environmental value stream maps (E2VSM). The proposed methodology is validated with an industrial case. 相似文献
326.
J.W.S. Longhurst J.G. Irwin T.J. Chatterton E.T. Hayes N.S. Leksmono J.K. Symons 《Atmospheric environment (Oxford, England : 1994)》2009,43(1):64-78
This paper considers the evolution of attempts to control and manage air pollution, principally but not exclusively focussing upon the challenge of managing air pollution in urban environments. The development and implementation of a range of air pollution control measures are considered. Initially the measures implemented primarily addressed point sources, a small number of fuel types and a limited number of pollutants. The adequacy of such a source-control approach is assessed within the context of a changing and challenging air pollution climate. An assessment of air quality management in the United Kingdom over a 50-year timeframe exemplifies the range of issues and challenges in contemporary air quality management. The need for new approaches is explored and the development and implementation of an effects-based, risk management system for air quality regulation is evaluated. 相似文献
327.
328.
329.
Reclamation and revegetation of fly ash disposal sites - Challenges and research needs 总被引:1,自引:1,他引:0
Haynes RJ 《Journal of environmental management》2009,90(1):43-53
Coal-fired power generation is a principal energy source throughout the world. Approximately, 70-75% of coal combustion residues are fly ash and its utilization worldwide is only slightly above 30%. The remainder is disposed of in landfills and fly ash basins. It is desirable to revegetate these sites for aesthetic purposes, to stabilize the surface ash against wind and water erosion and to reduce the quantity of water leaching through the deposit. Limitations to plant establishment and growth in fly ash can include a high pH (and consequent deficiencies of Fe, Mn, Cu, Zn and P), high soluble salts, toxic levels of elements such as B, pozzalanic properties of ash resulting in cemented/compacted layers and lack of microbial activity. An integrated organic/biotechnological approach to revegetation seems appropriate and should be investigated further. This would include incorporation of organic matter into the surface layer of ash, mycorrhizal inoculation of establishing vegetation and use of inoculated legumes to add N. Leaching losses from ash disposal sites are likely to be site-specific but a sparse number of studies have revealed enriched concentrations of elements such as Ca, Fe, Cd, Pb, and Sb in surrounding groundwater. This aspect deserves further study particularly in the longer-term. In addition, during weathering of the ash and deposition of organic matter during plant growth, a soil will form with properties vastly different to that of the parent ash. In turn, this will influence the effect that the disposal site has on the surrounding environment. Nevertheless, the effects of ash weathering and organic matter accumulation over time on the chemical, physical and biological properties of the developing ash-derived soil are not well understood and require further study. 相似文献
330.
Recycling plants that size, sort and wash construction and demolition waste can produce high quality aggregate. However, they also produce up to 80ton per hour of filter cake waste containing fine (<63mum) silt particles that is classified as inert waste and normally landfilled. This research investigated the potential to form geopolymers containing silt, which would allow this problematic waste to be beneficially reused as aggregate. This would significantly improve the economic viability of recycling plants that wash wastes. Silt filter cakes have been collected from a number of aggregate washing plants operating in the UK. These were found to contain similar aluminosilicate crystalline phases. Geopolymer samples were produced using silt and silt mixed with either metakaolin or pulverised fuel ash (PFA). Silt geopolymers cured at room temperature had average 7-day compressive strengths of 18.7MPa, while partial substitution of silt by metakaolin or PFA increased average compressive strengths to 30.5 and 21.9MPa, respectively. Curing specimens for 24h at 105 degrees C resulted in a compressive strength of 39.7MPa and microstructural analysis confirmed the formation of dense materials. These strengths are in excess of those required for materials to be used as aggregate, particularly in unbound applications. The implications of this research for the management of waste silt at construction and demolition waste washing plants are discussed. 相似文献