全文获取类型
收费全文 | 19189篇 |
免费 | 369篇 |
国内免费 | 3576篇 |
专业分类
安全科学 | 746篇 |
废物处理 | 1386篇 |
环保管理 | 2052篇 |
综合类 | 6033篇 |
基础理论 | 4663篇 |
环境理论 | 2篇 |
污染及防治 | 5289篇 |
评价与监测 | 1357篇 |
社会与环境 | 1208篇 |
灾害及防治 | 398篇 |
出版年
2024年 | 5篇 |
2023年 | 149篇 |
2022年 | 488篇 |
2021年 | 391篇 |
2020年 | 284篇 |
2019年 | 264篇 |
2018年 | 1778篇 |
2017年 | 1767篇 |
2016年 | 1560篇 |
2015年 | 673篇 |
2014年 | 825篇 |
2013年 | 1055篇 |
2012年 | 1345篇 |
2011年 | 2202篇 |
2010年 | 1363篇 |
2009年 | 1246篇 |
2008年 | 1603篇 |
2007年 | 1792篇 |
2006年 | 498篇 |
2005年 | 385篇 |
2004年 | 319篇 |
2003年 | 414篇 |
2002年 | 402篇 |
2001年 | 268篇 |
2000年 | 274篇 |
1999年 | 246篇 |
1998年 | 260篇 |
1997年 | 242篇 |
1996年 | 223篇 |
1995年 | 174篇 |
1994年 | 119篇 |
1993年 | 123篇 |
1992年 | 106篇 |
1991年 | 80篇 |
1990年 | 54篇 |
1989年 | 26篇 |
1988年 | 27篇 |
1987年 | 10篇 |
1986年 | 17篇 |
1985年 | 11篇 |
1984年 | 22篇 |
1983年 | 16篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1935年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 343 毫秒
981.
Remotely operated vehicle dive video recordings of deep-sea squid ink release were examined to determine species, ink release
type, release depth, and accompanying behavior/s. Ink release was commonly observed between the surface and 1,842.1 m in Monterey
Bay, CA, and surrounding waters. Six ink release types were observed: pseudomorphs, pseudomorph series, ink ropes, clouds/smokescreens,
diffuse puffs and mantle fills. Each species released ink throughout all or most of its depth range; inking was not limited
to shallow, sunlit waters. Individuals of each species produced one ink release type more commonly than other types, however,
multiple ink types could be released by individuals of all species. Common behaviors preceded and/or followed each release
type; pseudomorphs and pseudomorph series were generally associated with escape behaviors, while ink ropes, clouds, and puffs
normally involved the animal remaining adjacent to or amid the ink. Deep-sea squids may use ink for defensive purposes similar
to those of shallow-dwelling species when they release pseudomorphs, pseudomorph series, or large clouds, and may use ink
puffs in intra-specific communication. The function of ink ropes and mantle fills is unknown. 相似文献
982.
Mohamed F. Yassin 《Environmental monitoring and assessment》2012,184(6):3749-3760
This paper presents a model for coupling the statistics of wind velocity distribution and atmospheric pollutant dispersion.
The effect of wind velocity distribution is modeled as a three-dimensional finite-impulse response (3D-FIR) filter. A phase
space representation of the 3D-FIR filter window is discussed. The resulting pollutant dispersion is the multiplication in
the phase space of the 3-D Fourier transform of the pollutant concentration and the volume described by the filter window
coefficients. The shape of the filter window in the phase space enables representing such effects as vortex shedding thermal
currents, etc. The impact of spatial distribution of the sensors on the resulting pollutant spatial distribution and the 3-D
FIR filter model employed also discuss. The case of a neutrally buoyant plume emitted from an elevated point source in a turbulent
boundary layer considers. The results show that wind turbulence is an important factor in the pollutant dispersion and introduces
expected random fluctuations in pollutant distribution and leads to spreading the distribution due to wind mixing. 相似文献
983.
Nelzair A. Vianna Daniel Gonçalves Flavia Brandão Roberta P. de Barros Gilberto M. Amado Filho Rodrigo O. Meire João Paulo M. Torres Olaf Malm Argemiro D’Oliveira Júnior Leonardo R. Andrade 《Environmental science and pollution research international》2011,18(3):416-427
Purpose
The aims of this paper were to quantify the heavy metals (HM) in the air of different sites in Rio de Janeiro (RJ) and Salvador (SA) using Tillandsia usneoides (Bromeliaceae) as a biomonitor, and to study the morphology and elemental composition of the air particulate matter (PM) retained on the Tillandsia surface. 相似文献984.
Kuldeep Ojha 《Environment, Development and Sustainability》2011,13(1):203-215
Many Indian cities are facing serious problems in managing solid wastes with rise in population and urbanization. This article
assesses the existing state of municipal solid waste management (MSWM) in northern India with the aim of identifying the major
obstacles to its efficiency and the prospects for improvisation of the solid waste management system in the region. The existing
solid waste management system in the region is found to be highly inefficient. Primary and secondary collection, transportation
and open dumping are the only activities practiced that too in a non-technical manner. Many cities in region face serious
problems in managing solid wastes. The annual waste generation increases in proportion to the rises in population and urbanization.
This paper systematically assesses the obstacles in the existing solid waste management system in the urban areas of region
and also tries to assess the potentials for its improvisation. 相似文献
985.
986.
987.
Wei-Bo Chen Wen-Cheng Liu Nobuaki Kimura Ming-Hsi Hsu 《Environmental monitoring and assessment》2010,168(1-4):407-428
A three-dimensional hydrodynamic model was created to study the Danshuei River estuarine system and adjacent coastal ocean in Taiwan. The model was verified using measurements of the time-series water surface elevation, tidal current, and salinity from 1999. We conclude that our model is consistent with these observations. Our particle-tracking model was also used to explore the transport of particles released from the Hsin-Hai Bridge, an area that is heavily polluted. The results suggest that it takes a much longer time for the estuary to be flushed out under low freshwater discharge conditions than with high freshwater discharge. We conclude that the northeast and southwest winds minimally impact particle dispersion in the estuary. The particles fail to settle to the bottom in the absence of density-induced circulation. Our model was also used to simulate the ocean outfall at the Bali. Our experimental results suggest that the tidal current dominates the particle trajectories and influences the transport properties in the absence of a wind stress condition. The particles tend to move northeast or southwest along the coast when northeast or southwest winds prevail. Our data suggest that wind-driven currents and tidal currents play important roles in water movement as linked with ocean outfall in the context of the Danshuei River. 相似文献
988.
Dynamic Games in the Economics and Management of Pollution 总被引:1,自引:0,他引:1
Steffen Jørgensen Guiomar Martín-Herrán Georges Zaccour 《Environmental Modeling and Assessment》2010,15(6):433-467
The paper provides a survey of the literature which utilizes dynamic state-space games to formulate and analyze intertemporal,
many decision-maker problems in the economics and management of pollution. 相似文献
989.
Katrine Banke Nørgaard Nina Cedergreen 《Environmental science and pollution research international》2010,17(4):957-967
Background, aim and scope
The ergosterol biosynthesis-inhibiting (EBI) fungicide prochloraz can enhance the effect of other pesticides in a range of animal species. Approximately 50% of the fungicides used in Denmark are EBI fungicides. Hence, if they all have synergising potential, a risk assessment of pesticide mixtures based on additivity might not suffice. This study investigates the synergising potential of six different EBI fungicides representing the imidazoles (prochloraz), the triazoles (epoxiconazole, propiconazole and tebuconazole), the piperidines (fenpropidin) and the morpholines (fenpropimorph) together with the pyrethroid insecticide alpha-cypermethrin. 相似文献990.
Sumit Sinha Xiaofeng Liu Marcelo H. Garcia 《Environmental Modeling and Assessment》2013,18(5):567-592
As outfalls from various water reclamation plants, pumping stations, and combined sewer overflow outfalls discharge into the Chicago Area Waterway System (CAWS), an enhanced understanding of the final fate of crucial water quality state variables is of utmost importance. This paper reports the development and application of a 3D water quality model for a modified CAWS combined with the hydrodynamic kernel of Environmental Fluid Dynamics Code (EFDC). The modified CAWS is used to demonstrate the usefulness of the model while eliminating complications beyond the scope of this initial effort. The water quality model developed and presented in this research is a simplistic dissolved oxygen (DO)—biochemical oxygen demand model with the facility to account for the interaction between the water column and the bed. The aforementioned model is applied for the month of May 2009. The results from the hydrodynamic (EFDC) and water quality model is validated with the help of the observed data obtained from United States Geological Survey gaging stations and Metropolitan Water Reclamation District of Greater Chicago monitoring stations present inside the modeled domain. The 3D modeling captured the hydrodynamic and water-quality processes in CAWS in a satisfactory manner. Furthermore, modeling results showed and proved the interdependence of water quality characteristics in Bubbly Creek and CAWS with the effluent concentration from Racine Avenue Pumping Station situated at the head of Bubbly Creek, South Fork of South Branch of Chicago River. 相似文献