全文获取类型
收费全文 | 24604篇 |
免费 | 254篇 |
国内免费 | 231篇 |
专业分类
安全科学 | 639篇 |
废物处理 | 1091篇 |
环保管理 | 2925篇 |
综合类 | 3596篇 |
基础理论 | 6687篇 |
环境理论 | 6篇 |
污染及防治 | 6652篇 |
评价与监测 | 1793篇 |
社会与环境 | 1565篇 |
灾害及防治 | 135篇 |
出版年
2022年 | 274篇 |
2021年 | 225篇 |
2020年 | 162篇 |
2019年 | 185篇 |
2018年 | 356篇 |
2017年 | 375篇 |
2016年 | 565篇 |
2015年 | 419篇 |
2014年 | 675篇 |
2013年 | 1960篇 |
2012年 | 792篇 |
2011年 | 1094篇 |
2010年 | 941篇 |
2009年 | 944篇 |
2008年 | 1094篇 |
2007年 | 1150篇 |
2006年 | 964篇 |
2005年 | 836篇 |
2004年 | 801篇 |
2003年 | 847篇 |
2002年 | 773篇 |
2001年 | 1064篇 |
2000年 | 759篇 |
1999年 | 429篇 |
1998年 | 293篇 |
1997年 | 323篇 |
1996年 | 328篇 |
1995年 | 370篇 |
1994年 | 337篇 |
1993年 | 267篇 |
1992年 | 297篇 |
1991年 | 280篇 |
1990年 | 306篇 |
1989年 | 297篇 |
1988年 | 232篇 |
1987年 | 236篇 |
1986年 | 211篇 |
1985年 | 233篇 |
1984年 | 227篇 |
1983年 | 218篇 |
1982年 | 199篇 |
1981年 | 181篇 |
1980年 | 163篇 |
1979年 | 185篇 |
1978年 | 140篇 |
1977年 | 158篇 |
1975年 | 134篇 |
1974年 | 133篇 |
1973年 | 136篇 |
1972年 | 122篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Khan Syed Abdul Rehman Mathew Manoj Dominic P. D. D. Umar Muhammad 《Environment, Development and Sustainability》2022,24(9):10633-10665
Environment, Development and Sustainability - Environmental deterioration and global warming has created a substantial impact on international companies to incorporate eco-friendly, green supply... 相似文献
92.
Environment, Development and Sustainability - This study describes the results of groundwater table variation in Thanjavur District before and after the monsoon seasons. Groundwater-level data... 相似文献
93.
Russian Journal of Ecology - Abstract—We tested a hypothesis about the different abilities of alien and native plants to form arbuscular mycorrhizae. The studies were carried out in the... 相似文献
94.
Rate-temperature responses in scyphozoan medusae and polyps 总被引:1,自引:0,他引:1
The effects of temperature on oxygen consumption and spontaneous rhythmic activity have been investigated in various stages of the life histories of 3 species of jellyfish from the Chesapeake Bay, USA. All 3 species clearly show the ability to acclimate positively to temperature change. Thermal sensitivity of metabolism in the winter medusa Cyanea capillata fulva is fairly low at temperature intervals which are experienced in nature. Polyps of the two summer medusae, Chrysaora quinquecirrha and Aurelia aurita, show reduced metabolic sensitivity at temperatures normally accompanying high developmental activity and the onset of strobilation. 相似文献
95.
96.
97.
98.
99.
Shuyan Wang Lin Du Narcisse T. Tson Xiaotong Jiang Bo You Li Xu Zhaomin Yang Wenxing Wang 《环境科学学报(英文版)》2020,32(6):151-162
Methylglyoxal(CH_3COCHO,MG),which is one of the most abundant α-dicarbonyl compounds in the atmosphere,has been reported as a major source of secondary organic aerosol(SOA).In this work,the reaction of MG with hydroxyl radicals was studied in a 500 L smog chamber at(293±3) K,atmospheric pressure,(18±2)% relative humidity,and under different NOx and SO_2.Particle size distribution was measured by using a scanning mobility particle sizer(SMPS) and the results showed that the addition of SO_2 can promote SOA formation,while different NOx concentrations have different influences on SOA production.High NOx suppressed the SOA formation,whereas the particle mass concentration,particle number concentration and particle geometric mean diameter increased with the increasing NOx concentration at low NOx concentration in the presence of SO_2.In addition,the products of the OH-initiated oxidation of MG and the functional groups of the particle phase in the MG/OH/SO_2 and MG/OH/NOx/SO_2 reaction systems were detected by gas chromatography mass spectrometry(GC-MS) and attenuated total reflection fourier transformed infrared spectroscopy(ATR-FTIR) analysis.Two products,glyoxylic acid and oxalic acid,were detected by GC-MS.The mechanism of the reaction of MG and OH radicals that follows two main pathways,H atom abstraction and hydration,is proposed.Evidence is provided for the formation of organic nitrates and organic sulfate in particle phase from IR spectra.Incorporation of NOx and SO_2 influence suggested that SOA formation from anthropogenic hydrocarbons may be more efficient in polluted environment. 相似文献
100.
The distribution and sources of organochlorine pesticides (OCPs) in air and surface waters were monitored in Nairobi City using triolein-filled semipermeable membrane devices (SPMDs). The SPMDs were extracted by dialysis using n-hexane, followed by cleanup by adsorption chromatography on silica gel cartridges. Sample analysis was done by GC-ECD and confirmed by GC–MS. Separation of means was achieved by analysis of variance, followed by pair-wise comparison using the t-test (p≤ 0.05). The total OCPs ranged between 0.018 – 1.277 ng/m3 in the air and <LOD – 1391.000 ng/m3 in surface waters. Based on the results, the means of Industrial Area, Dandora and Kibera were not significantly different (p≤ 0.05), but were higher (p≤ 0.05) than those of City square and Ngong’ Forest. The results revealed non-significant (p≤ 0.05) contribution of long-range transport to OCP pollution in Nairobi City. This indicated possible presence of point sources of environmental OCPs in the city. The water-air fugacity ratios indicated that volatilization and deposition played an important role in the spatial distribution of OCPs in Nairobi City. This indicated that contaminated surface waters could be major sources of human exposure to OCPs, through volatilization. The incremental lifetime cancer risks (ILCR) determined from inhalation of atmospheric OCPs were 2.3745 × 10?13 – 1.6845 × 10?11 (adult) and 5.5404 × 10?13 – 3.9306 × 10?11 (child) in the order: Dandora > Kibera > Industrial Area > City Square > Ngong’ Forest. However, these were lower than the USEPA acceptable risks, 10?6 – 10?4. This study concluded that atmospheric OCPs did not pose significant cancer risks to the residents. 相似文献