全文获取类型
收费全文 | 426篇 |
免费 | 5篇 |
国内免费 | 36篇 |
专业分类
安全科学 | 168篇 |
废物处理 | 28篇 |
环保管理 | 43篇 |
综合类 | 103篇 |
基础理论 | 25篇 |
污染及防治 | 69篇 |
评价与监测 | 25篇 |
社会与环境 | 5篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 17篇 |
2022年 | 10篇 |
2021年 | 34篇 |
2020年 | 31篇 |
2019年 | 12篇 |
2018年 | 11篇 |
2017年 | 6篇 |
2016年 | 12篇 |
2015年 | 23篇 |
2014年 | 28篇 |
2013年 | 33篇 |
2012年 | 25篇 |
2011年 | 21篇 |
2010年 | 11篇 |
2009年 | 19篇 |
2008年 | 23篇 |
2007年 | 29篇 |
2006年 | 22篇 |
2005年 | 4篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 13篇 |
2001年 | 9篇 |
2000年 | 7篇 |
1999年 | 10篇 |
1998年 | 9篇 |
1997年 | 7篇 |
1996年 | 4篇 |
1995年 | 5篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有467条查询结果,搜索用时 15 毫秒
151.
A comparison between superfine magnesium hydroxide powders and commercial dry powders on fire suppression effectiveness 总被引:1,自引:0,他引:1
Kaiqian Kuang Xin Huang Guangxuan Liao 《Process Safety and Environmental Protection》2008,86(3):182-188
The effectiveness of superfine magnesium hydroxide powders and commercial dry powder in fire suppression were compared in a laboratory-scale, immovable fire suppression apparatus. The investigation focused on their suppression effectiveness under various pressures. It likewise studied the relationship between the powders’ surface structures and their effectiveness on fire suppression. The microcosmic structure of the powders was observed by scanning electron microscope (SEM), while the Thermal Gravity Analysis (TGA) technique was used to analyze the thermal behavior of the superfine magnesium hydroxide powders. By analyzing the results, it could be concluded that the pressure, the particle size, and the microcosmic structure of the powders’ surface mainly decide the capability of the powders to extinguish the fire. Comparing this with commercial dry powders, superfine magnesium hydroxide powders extinguished the fire in less than 10 s. 相似文献
152.
The paper presents the application of thermal remote sensing for mapping hydrocarbon polluted sites. This has been achieved by mono-window algorithm for land surface temperature (LST) measurements, using multi-date band 6 data of Landsat Thematic Mapper (TM). The emissivity, transmittance and mean atmospheric temperature were used as critical factors to estimate LST. The changes in the surface emissivity due to oil pollution alter the apparent temperature, which was used as a recognition element to map out oil polluted surfaces. The LST contrast was successfully used to map spatial distribution of hydrocarbon pollution in the Burgan Oil field area of Kuwait. The methodology can be positively used to detect waste dumping, oil spills in oceans and ports, besides environmental management of oil pollution at or near the land surface. 相似文献
153.
This study investigated the sorption characteristics and recovery of selected heavy metal Cd(II) from K-feldspar and sepiolite, representative soil components, using rhamnolipid biosurfactant. Although the proposed technique was classified as a soil bioremediation process, it can also be applied to treatment of waste waters containing Cd(II) ions with minor modifications. The effect of initial Cd(II) concentration on sorption capacity was characterized by determining the sorption isotherms. Of the four models examined, the Freundlich model showed the best fit for the sorption of Cd(II) on K-feldspar, whereas the Langmuir-model was used successfully to characterize the sorption of Cd(II) on sepiolite. Although a high Cd(II) uptake of 7.49 mmol/kg by K-feldspar was obtained, sepiolite was a superior Cd(II) accumulater, with a maximum Cd(II) uptake of 24.66 mmol Cd(II)/kg. The presence of Cd(II) in the sepiolite or K-feldspar prior to addition of the rhamnolipid generally resulted in less rhamnolipid sorption to sepiolite or K-feldspar. The maximum Cd(II) desorption efficiency by rhamnolipid from K-feldspar was substantially higher than that of sepiolite and determined to be 96% of the sorbed Cd(II), whereas only 10.1% of the sorbed Cd(II) from sepiolite was recovered by rhamnolipid solution. 相似文献
154.
Spatial concentration distribution of a chemical in an indoor environment is an important factor in the evaluation of chemical nuisances. However, straightforward techniques for the determination of this distribution are not very common and usually limited in their application. Sorptive sampling using polydimethylsiloxane-coated stir bars and the combination of active and diffusive sampling were shown to allow uncomplicated spatial concentration profiling of multiple compounds in an indoor environment. The validity of the approach was demonstrated in the analysis of the spatial concentration distribution of a pyrethroid insecticide in a common bedroom. The relative concentrations of allethrin and piperonyl butoxide were profiled throughout the room upon the application of an insecticide vaporizer. 相似文献
155.
Effects of long-term soil amendment with sewage sludges on soil humic acid thermal and molecular properties 总被引:2,自引:0,他引:2
Sewage sludges are frequently used as soil amendments due to their high contents of organic matter and nutrients, particularly N and P. However, their effects upon the chemistry of soil humic acids, one of the main components of the soil organic matter, need to be more deeply studied in order to understand the relation between organic matter structure and beneficial soil properties. Two sewage sludges subjected to different types of pre-treatment (composted and thermally dried) with very different chemical compositions were applied for three consecutive years to an agricultural soil under long-term field study. Thermal analysis (TG–DTG–DTA) and solid-state 13C NMR spectroscopy were used to compare molecular and structural properties of humic acids isolated from sewage sludges, and to determine changes in amended soils. Thermally dried sewage sludge humic acids showed an important presence of alkyl and O/N-alkyl compounds (70%) while composted sludge humic acids comprised 50% aromatic and carbonyl carbon. In spite of important differences in the initial chemical and thermal properties of the two types of sewage sludges, the chemical and thermal properties of the soil humic acids were quite similar to one another after 3 years of amendment. Long-term application of both sewage sludges resulted in 80–90% enrichment in alkyl carbon and organic nitrogen contents of the soil humic acid fraction. 相似文献
156.
Because of recent volume increases, appropriate management of plastic recycling, which generates various organic compounds, is required to ensure the chemical safety of the processes. The processing temperature and resin type are the important factors determining both the efficiency of the processes and the emission of chemicals. Therefore, we studied the thermal degradation of various plastics at various temperatures from 70 to 300 °C under oxygen-present conditions to identify the semi-volatile organic compounds (SVOCs) emitted and to understand their thermal behaviors. The plastics examined were nitrogen-containing resins, such as polyamide 6, polyurethane, melamine formaldehyde, urea formaldehyde and acrylonitrile-butadiene-styrene. Major commodity plastics were also investigated for comparison. In total, more than 500 SVOCs were detected as emissions from plastics. While various nitrogen-containing SVOCs were detected from nitrogen-containing resins, the major commodity plastics released only these, which possibly were included as additives. These results indicate that the nitrogen atoms in the SVOCs emitted originated from the resins and additives, and not from ambient air at low temperature. As a result of the detection of raw materials, degradation chemicals and by-products of the polymers in the emissions, we found that the variation in chemical species is dependent on the resins. Additives were also emitted from all the resins, meaning that these chemicals were also released to the environment at the temperature examined. In most cases, the numbers and concentrations of SVOCs increased with increasing heating temperature. The variation of thermal behaviors of SVOCs was related to the origins and chemical species of SVOCs. 相似文献
157.
158.
Julius Otutu Oseji 《The Environmentalist》2007,27(2):311-314
Environmental Pollution now persist in Nigeria especially the oil-rich regions of Delta State. One of these problems is due
to gas flaring. Thermal gradient resulting from the gas flared at Kwale/Okpai gas plant is hereby reported. Surface temperature
variations with distance from the flare point were investigated for the four cardinal directions. The results show a surface
temperature elevation of about 3.7° C above the mean normal daily temperature within a radius of 270 M. Hence the thermal
equilibrium has been altered. This increase in temperature has undesirable effect on man and his environment especially on
the socio-economic lives and activities of the inhabitants. It is therefore necessary that Government Agencies empowered to
monitor environment such as Federal Environmental Protection Agency (FEPA) should embark on adequate remediation activities
in order to stop the environmental degradation before enormous and permanent damage is caused. Furthermore, the companies
involved in the gas flaring should be made to be concerned with the danger they may be causing the inhabitants in particular
and the populace in general. 相似文献
159.
Qingsong Wang Jinhua Sun Xiaolin Yao Chunhua Chen 《Journal of Loss Prevention in the Process Industries》2006,19(6):561-569
With the extensive applications of lithium-ion batteries, many batteries explosion accidents were reported. The thermal stability of lithium-ion battery electrolyte could substantially affect the safety of lithium-ion battery. The C80 micro calorimeter was used to study the thermal stability of several commonly used organic solvents and electrolytes. The samples were heated in argon atmosphere and air atmosphere, respectively. The chemical reaction kinetics was supposed to fit by an Arrhenius law, then the self-accelerating decomposition temperature was calculated. It is found that most of the samples are stable in argon atmosphere while decomposing in air atmosphere, and the single organic solvent is more stable than the electrolyte generally. 相似文献
160.