全文获取类型
收费全文 | 253篇 |
免费 | 7篇 |
国内免费 | 45篇 |
专业分类
安全科学 | 12篇 |
废物处理 | 22篇 |
环保管理 | 13篇 |
综合类 | 70篇 |
基础理论 | 41篇 |
污染及防治 | 110篇 |
评价与监测 | 23篇 |
社会与环境 | 9篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 11篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 12篇 |
2017年 | 16篇 |
2016年 | 6篇 |
2015年 | 11篇 |
2014年 | 7篇 |
2013年 | 35篇 |
2012年 | 12篇 |
2011年 | 22篇 |
2010年 | 15篇 |
2009年 | 14篇 |
2008年 | 23篇 |
2007年 | 13篇 |
2006年 | 9篇 |
2005年 | 15篇 |
2004年 | 4篇 |
2003年 | 12篇 |
2002年 | 11篇 |
2001年 | 6篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 2篇 |
1997年 | 5篇 |
1996年 | 6篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有305条查询结果,搜索用时 31 毫秒
21.
SO2 remains a common air pollutant, almost half of the world’s population uses coal and biomass fuels for domestic energy. Limited evidence suggests that exposure to SO2 may be associated with neurotoxicity and increased risk of hospitalization and mortality of many brain disorders. However, our understanding of the mechanisms by which SO2 causes harmful insults on neurons remains elusive. To explore the molecular mechanism of SO2-induced neurotoxic effects in hippocampal neurons, we evaluated the synaptic plasticity in rat hippocampus after exposure to SO2 at various concentrations (3.5 and 7 mg m−3, 6 h d−1, for 90 d) in vivo, and in primary cultured hippocampal neurons (DIV7 and DIV14) after the treatment of SO2 derivatives in vitro. The results showed that SYP, PSD-95, NR-2B, p-ERK1/2 and p-CREB were consistently inhibited by SO2/SO2 derivatives in more mature hippocampal neurons in vivo and in vitro, while the effects were opposite in young hippocampal neurons. Our results indicated that in young neurons, SO2 exposure produced neuronal insult is similar to ischemic injury; while in more mature neurons, SO2 exposure induced synaptic dysfunctions might participate in cognitive impairment. The results implied that SO2 inhalation could cause different neuronal injury during brain development, and suggested that the molecular mechanisms might be involved in the changes of synaptic plasticity. 相似文献
22.
Kim SS Lee SM Park KH Kwon DW Hong SC 《Journal of the Air & Waste Management Association (1995)》2011,61(5):552-558
This study investigated the effect of adding vanadium (V) to natural manganese oxide (NMO) in ammonia (NH3) selective catalytic reduction (SCR). The addition of V to NMO decreased the catalytic activity at low temperatures by blocking the active site. However, the enhancement of catalytic activity was achieved by controlling NH3 oxidation at high temperatures. From the NH3 temperature programmed desorption and oxygen on/off test, it was confirmed that the amount of Lewis acid site and active lattice oxygen of the catalyst affects the catalytic performance at low temperature. 相似文献
23.
24.
Eom YS Hong JH Lee SJ Lee EJ Cha JS Lee DG Bang SA 《Journal of the Air & Waste Management Association (1995)》2006,56(11):1518-1524
The development of local, accurate emission factors is very important for the estimation of reliable national emissions and air quality management. For that, this study is performed for pollutants released to the atmosphere with source-specific emission tests from the semiconductor manufacturing industry. The semiconductor manufacturing industry is one of the major sources of air toxics or hazardous air pollutants (HAPs); thus, understanding the emission characteristics of the emission source is a very important factor in the development of a control strategy. However, in Korea, there is a general lack of information available on air emissions from the semiconductor industry. The major emission sources of air toxics examined from the semiconductor manufacturing industry were wet chemical stations, coating applications, gaseous operations, photolithography, and miscellaneous devices in the wafer fabrication and semiconductor packaging processes. In this study, analyses of emission characteristics, and the estimations of emission data and factors for air toxics, such as acids, bases, heavy metals, and volatile organic compounds from the semiconductor manufacturing process have been performed. The concentration of hydrogen chloride from the packaging process was the highest among all of the processes. In addition, the emission factor of total volatile organic compounds (TVOCs) for the packaging process was higher than that of the wafer fabrication process. Emission factors estimated in this study were compared with those of Taiwan for evaluation, and they were found to be of similar level in the case of TVOCs and fluorine compounds. 相似文献
25.
金荞麦药理作用研究进展 总被引:2,自引:0,他引:2
金荞麦能抗菌消炎、抑制肿瘤,同时还可以增强巨噬细胞的吞噬功能,提高机体的免疫能力;药理实验证明金荞麦还具有降脂降糖、祛痰镇咳和抑制血小板聚集等作用.参36. 相似文献
26.
Eupolymnia nebulosa (Montagu) is a widely distributed terebellid polychaete that builds its tubes on the coastal shelf in areas with mixed soft
and hard bottoms. From a long-term survey in the Bay of Banyuls, France (NW Mediterranean), we found an advancement of the
timing of the spawning period coincident with a delayed breakdown of the thermocline. We postulate that persistent high temperatures
can influence gamete development by stimulating oocyte growth, resulting in earlier spawning. During 1992 and 1993, we used
a between-individuals experimental approach to assess the possible effect of temperature on oocyte growth based on: (1) determination
of the growing fraction of the oocyte population (i.e. oocyte net growth); (2) identification of differences in oocyte growth-rate
among females; (3) comparison of non-significantly different size-distributions of the growing oocyte fraction (net oocyte
size-distributions) at the beginning of the experiments with those at the end. No effect of temperature on oocyte growth was
detectable at the population level, but a positive individual response to prolonged high temperature was evident. Thus, the lack of a significant response by the population to prolonged
high temperature does not imply a lack of individual response. We propose a model of oocyte-growth dynamics based on temperature
that incorporates previous observations of extended oogenesis and oocyte growth during periods of both increasing and decreasing
temperature and on the scattered pattern of oocyte size-distributions at the onset of spawning.
Received: 4 November 1996 / Accepted: 18 January 1997 相似文献
27.
本文以煤气化工程的典型实例分析为基础,通过对气源厂经济效益的分析,提出了以气化替煤量和节煤量两项指标,进行宏观经济效益、社会效益和环境效益的综合效益分析的步骤及相应的计算公式与方法。 相似文献
28.
Microwave process for volatile organic compound abatement 总被引:5,自引:0,他引:5
The CHA Corporation has completed the U.S. Air Force Phase II Small Business Innovation Research program to investigate the feasibility of using a novel microwave-based process for the removal and destruction of volatile organic compounds (VOCs) in effluents from noncombustion sources, such as paint booth ventilation streams. Removal of solvents by adsorption, followed by the regeneration of saturated granular activated carbon (GAC) by microwave energy, was achieved in a single fixed-bed reactor. Microwave regeneration of the fixed-bed-saturated carbon restored the original GAC adsorption capacity. After 20 adsorption/regeneration cycles, the adsorption capacity dropped from 13.5 g methyl ethyl ketone (MEK)/100 g GAC to 12.5 g MEK/100 g GAC. During microwave regeneration of the GAC fixed bed, the concentrated desorbed paint solvent was oxidized by passing the solvent mixture through a fixed bed of an oxidation catalyst mixed with silicon carbide in a microwave reactor. A 98% oxidation efficiency was consistently achieved from the oxidation of VOCs in the microwave catalytic reactor. 相似文献
29.
Choi JH Kim YH Joo DJ Choi SJ Ha TW Lee DH Park IH Jeong YS 《Journal of the Air & Waste Management Association (1995)》2003,53(1):92-101
The characteristics of ammonia removal by two types of biofilter (a standard biofilter with vertical gas flow and a modified biofilter with horizontal gas flow) were investigated. A mixture of organic materials such as compost, bark, and peat was used as the biofilter media based on the small-scale column test for media selection. Complete removal capacity, defined as the maximum inlet load of ammonia that was completely removed, was obtained. The modified biofilter showed complete removal up to 1.0 g N/kg dry material/day. However, the removal capacity of the standard biofilter started to deviate from complete removal around 0.4 g N/kg dry material/day, indicating that the modified biofilter system has higher removal efficiency than the standard upflow one. In kinetic analysis of the biological removal of ammonia in each biofilter system, the maximum removal rate, Vm, was 0.93 g N/kg dry material/day and the saturation constant, Ks, was 32.55 ppm in the standard biofilter. On the other hand, the values of Vm and Ks were 1.66 g N/kg dry material/day and 74.25 ppm, respectively, in the modified biofilter system. 相似文献
30.
Microwave regeneration of activated carbon used for removal of solvents from vented air 总被引:4,自引:0,他引:4
A microwave regeneration of activated carbon used to remove organic solvents from vented air has been investigated. Methyl ethyl ketone (MEK), acetone, and tetrachloroethylene (TCE) vapors were removed from vented air through adsorption onto granular activated carbon. The saturated carbon was then regenerated in a microwave field, where the solvent was quickly desorbed and recovered from the inner pores of the carbon granules. The microwave-induced regeneration restored the original adsorption capacity and surface area of the activated carbon. 相似文献