全文获取类型
收费全文 | 29519篇 |
免费 | 326篇 |
国内免费 | 221篇 |
专业分类
安全科学 | 833篇 |
废物处理 | 1061篇 |
环保管理 | 4036篇 |
综合类 | 4663篇 |
基础理论 | 8565篇 |
环境理论 | 21篇 |
污染及防治 | 7709篇 |
评价与监测 | 1743篇 |
社会与环境 | 1244篇 |
灾害及防治 | 191篇 |
出版年
2022年 | 178篇 |
2021年 | 180篇 |
2019年 | 215篇 |
2018年 | 389篇 |
2017年 | 380篇 |
2016年 | 556篇 |
2015年 | 491篇 |
2014年 | 679篇 |
2013年 | 2134篇 |
2012年 | 842篇 |
2011年 | 1252篇 |
2010年 | 1029篇 |
2009年 | 1035篇 |
2008年 | 1250篇 |
2007年 | 1332篇 |
2006年 | 1184篇 |
2005年 | 1006篇 |
2004年 | 1005篇 |
2003年 | 941篇 |
2002年 | 939篇 |
2001年 | 1241篇 |
2000年 | 860篇 |
1999年 | 549篇 |
1998年 | 427篇 |
1997年 | 435篇 |
1996年 | 442篇 |
1995年 | 483篇 |
1994年 | 441篇 |
1993年 | 398篇 |
1992年 | 414篇 |
1991年 | 375篇 |
1990年 | 376篇 |
1989年 | 412篇 |
1988年 | 347篇 |
1987年 | 301篇 |
1986年 | 277篇 |
1985年 | 306篇 |
1984年 | 286篇 |
1983年 | 321篇 |
1982年 | 322篇 |
1981年 | 271篇 |
1980年 | 244篇 |
1979年 | 270篇 |
1978年 | 229篇 |
1977年 | 195篇 |
1976年 | 200篇 |
1975年 | 192篇 |
1974年 | 172篇 |
1973年 | 171篇 |
1972年 | 198篇 |
排序方式: 共有10000条查询结果,搜索用时 656 毫秒
611.
Non-aqueous electrolyte solutions are nowadays intensively studied owing to their unique properties for their application in various electrochemical devices and procedures. Important advances have already been made in high-energy primary batteries, wet capacitors, electroplating, phase-transfer catalysis and electro-organic synthesis; advances are expected in further fields such as high-energy secondary batteries, non-emissive displays, solar cells, thin-film procedures and coating. A survey is given both for successful recent applications and expectations. 相似文献
612.
613.
614.
615.
M. Schwartz M. Super J. Schmidtke C. Buys M. Farrall D. Halley M. Krawczak J. E. Poncin D. Loukopoulos M. Devoto 《黑龙江环境通报》1988,8(8):619-624
This paper presents data collected in Europe on 107 prenatal diagnoses of cystic fibrosis (CF) using linked DNA markers. To date, 38 children have been born without CF, as predicted, demonstrating the present rapid move from research to clinical genetic service. 相似文献
616.
617.
The application of ultrasonic-electrolysis process for the removal of copper is studied.In the ultrasonic field cavitation acts as jets and agitates the solution and breaks the barrier layer between the cathode surface and the bulk of the solution.Thus increases metal deposition on the cathode surface.The results show that an ultrasonic field is successful for the removal of low copper concentrations in solution. 相似文献
618.
Colombo JC Cabello M Arambarri AM 《Environmental pollution (Barking, Essex : 1987)》1996,94(3):355-362
The biodegradation of aliphatic and aromatic hydrocarbons by natural soil microflora and seven fungi species, including imperfect strains and higher level lignolitic species, is compared in a 90-day laboratory experiment using a natural, not-fertilized soil contaminated with 10% crude oil. The natural microbial soil assemblage isolated from an urban forest area was unable to significantly degrade crude oil, whereas pure fungi cultures effectively reduced the residues by 26-35% in 90 days. Normal alkanes were almost completely degraded in the first 15 days, whereas aromatic compounds (phenanthrene and methylphenanthrenes) exhibited slower kinetics. Aspergillus terreus and Fusarium solani, isolated from oil-polluted areas, produced the more efficient attack of aliphatic and aromatic hydrocarbons, respectively. Overall, imperfect fungi isolated from polluted soils showed a somewhat higher efficiency, but the performance of unadapted, indigenous, lignolitic fungi was comparable, and all three species, Pleurotus ostreatus, Trametes villosus and Coriolopsis rigida, effectively degraded aliphatic and aromatic components. The simultaneous, multivariate analysis of 22 parameters allowed the elucidation of a clear reactivity trend of the oil components during biodegradation: lower molecular weight n-alkanes > phenanthrene > 3-2-methylphenanthrenes > intermediate chain length n-alkanes > longer chain length n-alkanes > isoprenoids approximately 9-1-methylphenanthrenes. Irrespective of the individual degrading capacities, all fungi species tested seem to follow this decomposition sequence. 相似文献
619.
Effects of ethylenediurea (EDU) on ozone-induced acceleration of foliar senescence in potato (Solanum tuberosum L.) 总被引:1,自引:0,他引:1
Experiments were conducted to examine the effects of the anti-ozonant ethylenediurea (EDU) and chronic ozone (O3) exposure on leaf physiology and senescence in an O3-sensitive potato cultivar (Solanum tuberosum L. cv. Norland). A dose-response experiment showed that an EDU concentration of 15 mg l(-1) soil (given as a soil drench) provided complete protection from accelerated foliar senescence induced by exposure to 0.1 microl l(-1) O3 for 5 h day(-1) for 11 days. EDU doses of 45 and 75 mg active ingredient l(-1) soil also gave protection but were associated with symptoms of toxicity and delayed senescence. In further experiments, plants were given 0 or 15 mg EDU l(-1) soil and exposed to clean air or 0.1 microl l(-1) O3 for 5 h day(-1) for 14 days. Chronic O3 exposure in the absence of EDU resulted in accelerated foliar senescence, characterized by early declines in net photosynthesis and Rubisco quantity in O3-treated plants relative to controls. EDU in the presence of O3 gave complete protection against symptoms of accelerated senescence. Senescence was not delayed in plants that received EDU in the absence of O3, and no symptoms of EDU toxicity were evident. The results suggest that EDU-induced tolerance to O3 was not based on 'anti-senescent' properties of this anti-ozonant. 相似文献
620.
In this experiment, the impacts of pulp mill effluent irrigation, Fraser cottonwood (Populus deltoides 'Fraser') seedlings, and pulp sludge and manure soil amendments on sodium accumulation and distribution in the soil profile were evaluated during a 6 month greenhouse study. Sludge soil amendments and wastewater irrigation did not reduce stem biomass production of the cottonwood. Increased stem biomass production associated with manure soil amendments resulted in greater total uptake of sodium into stem material. This uptake was 0.002% of wastewater sodium inputs. In containers with seedlings, sodium concentrations were less in the surface horizon and more in the lower horizons than in containers with no seedlings. Infiltration rates and total sodium accumulation in the soil profile were not affected by the presence of Fraser cottonwood or the application of sludge or manure amendments to soil. 相似文献