全文获取类型
收费全文 | 628篇 |
免费 | 13篇 |
国内免费 | 9篇 |
专业分类
安全科学 | 18篇 |
废物处理 | 54篇 |
环保管理 | 82篇 |
综合类 | 51篇 |
基础理论 | 159篇 |
环境理论 | 1篇 |
污染及防治 | 210篇 |
评价与监测 | 46篇 |
社会与环境 | 12篇 |
灾害及防治 | 17篇 |
出版年
2022年 | 9篇 |
2021年 | 9篇 |
2020年 | 5篇 |
2019年 | 9篇 |
2018年 | 12篇 |
2017年 | 15篇 |
2016年 | 16篇 |
2015年 | 13篇 |
2014年 | 21篇 |
2013年 | 52篇 |
2012年 | 35篇 |
2011年 | 30篇 |
2010年 | 24篇 |
2009年 | 36篇 |
2008年 | 38篇 |
2007年 | 47篇 |
2006年 | 29篇 |
2005年 | 23篇 |
2004年 | 25篇 |
2003年 | 25篇 |
2002年 | 17篇 |
2001年 | 15篇 |
2000年 | 9篇 |
1999年 | 11篇 |
1998年 | 7篇 |
1997年 | 3篇 |
1996年 | 7篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 6篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 6篇 |
1988年 | 7篇 |
1987年 | 7篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1981年 | 3篇 |
1979年 | 7篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1972年 | 3篇 |
1971年 | 3篇 |
1970年 | 4篇 |
1967年 | 3篇 |
排序方式: 共有650条查询结果,搜索用时 812 毫秒
641.
Summer time haze characteristics of the urban atmosphere of Gwangju and the rural atmosphere of Anmyon, Korea 总被引:4,自引:0,他引:4
An extensive visibility monitoring was carried out simultaneously in the urban area of Gwangju and the rural area of Anmyon,
Korea. This study examines patterns of visibility impairment and haze-forming pollutant concentrations on both sites resulting
from natural and anthropogenic sources of gases and particles. Optical visibility measurements by a transmissometer, a nephelometer
and an aethalometer provide aerosol light extinction, scattering, and absorption coefficients for both sites. In order to
investigate the physico-chemical characteristics of atmospheric aerosols, aerosol samples were collected by various aerosol
samplers at GJVMS (Gwangju Visibility Monitoring Station) and at KGAWO (Korea Global Atmosphere Watch Observatory), respectively.
In addition, haze characteristics causing visibility impairment at those two sites were analyzed to obtain source contributions
by regionally transported aerosols using grid analysis and display system (GrADS) from NECP reanalysis data. During the intensive
monitoring period, ammonium sulfate was dominantly responsible for the fine particle mass loading at GJVMS, whereas organic
carbon was the largest contributor at KGAWO. Light scattering by particles accounted for 52.8 to 81.3% of the range at the
urban site, GJVMS and for 72.1 to 94.2% of the range at the rural site, KGAWO. Light absorption by the EC and NO2 was between 14.5 and 34.8% at GJVMS, which was higher than the observed 1.1 ∼ 6.8% at KGAWO, respectively. Light scattering
by aerosol was higher in the rural area than in the urban area. And organic carbon concentration was observed to be significantly
higher than the concentration of elemental carbon at KGAWO. These haze-forming carbonaceous particles originate from anthropogenic
pollutants at the urban atmosphere but they can be produced by natural environments such as marine and forest at the rural
atmosphere. 相似文献
642.
An electroanalytical method has been developed for the determination of the herbicides ethalfluralin[N-ethyl-N-(2-methyl-2-propenyl)-2,6-dinitro-4-(trifluoromethyl) bezenamine] and methalpropalin [N-(2-methyl-2-propenyl)-2, 6-dinitro-N-propyl-4 (trifluoromethyl) benzenamine] by differential pulse adsorptive stripping voltammetry (DP-AdSV) on a hanging mercury drop electrode (HMDE) with universal buffer as supporting electrolyte. The optimum adsorption conditions were found to be pH 6.0, an accumulation potential of -0.6 V (HMDE vs SCE), an accumulation time of 80 s. and scan rate 45 mVs(-1). Calibration curve is linear in the range 1.30 x 10(-9) to 1.32 x 10(-5) M of ethalfluralin and 1.13 x 10(-5) to 2.0 x 10(-8) M of methalpropalin with detection limits of 1.08 x 10(-9) and 1.87 x 10(-8) M, respectively. The relative SD and correlation coefficients were found to be 1.24%, 0.998 and 1.34%, 0.995, respectively for ten replicates. The method is applied to the determination of the ethalfluralin and methalpropalin in formulations and environmental matrices. 相似文献
643.
Brett A. Bryan Stefan Hajkowicz Steve Marvanek Mike D. Young 《Environmental Modeling and Assessment》2009,14(3):375-390
We integrate information from several disparate data sources including agricultural statistics and remote sensing to quantify
and map the distribution and dynamics of agricultural returns to land and water resources from 1996/1997 to 2000/2001 in the
Murray–Darling Basin (MDB), Australia. Total profit to agriculture was estimated at AUD3.86B in 1996/1997 and AUD3.73B in
2000/2001. The mapping reveals a high spatial concentration of economic returns to land and water resources from agriculture.
Dryland agriculture covers over 82% of the study area. Irrigated agriculture covers 1.7% of the land area (2000/2001) but
returns one third of the total profit to agriculture. We found that around 80% of the profit to agriculture comes from just
over 5% of the land area. The results from this regional scale economic mapping can inform regulatory policy and public investments
in natural resource management through targeting industries and regions that provide low marginal returns to the natural resource
base. 相似文献
644.
The aim of this study was to determine if Arase dam gate removal and flushing elevated concentrations of any trace elements in Kuma River and Yatsushiro Bay sediments or caused riverine environmental change. The Arase dam gate on the Kuma River was opened in April 2010. Surface and bottom sediments were compared using 10-cm-long cores (2011) and two grain size fractions. Surface sediment data from 2002, 2012, and 2013 from the Kuma River and Yatsushiro Bay were also compared. The sediments were analyzed using XRF for 23 elements, and the grain size analysis was done. The short core surface and bottom sediments do not show major chemical changes, and therefore, may not represent post-and pre-dam sediments. Results based on 2011 samples show that the removal of the Arase dam gates in 2010 has been geoenvironmentally beneficial due to the decrease of environmentally related trace elements Pb and Zn in 2013. However, a slight increase in the levels of Cr, Cu, Zr, and Nb in 2013 indicates that periodic flushing in winter leads to elevation in these elements due to an increase in the fine fraction. Metal enrichment factors (EF) in 2002 are higher and these have decreased by 2013. Some elements exceed environmental guidelines, but this is due to natural background values, and there is no anthropogenic contamination. Thus, the environment of the river and bay has been significantly improved due to the dam opening. This result suggests that assessment and environmental monitoring studies are very important for dam management and future decision making. 相似文献
645.
Evaluation of maturity parameters and heavy metal contents in composts made from animal manure 总被引:8,自引:0,他引:8
The objective of this study was to evaluate a variety of maturity indices and heavy metal concentrations in the composting process. A full-scale study was performed on animal manures (dairy:beef:swine = 50%:30%:20%, w/w) mixed with sawdust using a self-screwed turner over a time period of 63 days. Several chemical compost characteristics and germination indices were monitored on samples collected weekly at a prototype composting facility. NH(4)-N concentrations decreased during the composting time, on the contrary NO(3)-N concentrations increased sharply after 30 days. As composting proceeded, the humic acids content increased from 1.45% to 2.70% of the organic carbon content, whereas the fulvic acids content decreased gradually. Temperature in the compost pile and concentration of NH(3) averaged 32.4 degrees C and 12.9 ppm at the initial composting phase and 69.5 degrees C and 47.3 ppm at the active bio-oxidation composting phase, respectively. Seed germination and germination index (GI) increased during the composting process, and the compost samples at the end of composting phase had GI values greater than 120. Among the composting processes, there were significant differences (p<0.05) in concentration of Zn, Cu and Pb in the compost. In conclusion, the suggested maturity parameter values and metal concentrations of composted animal manures can provide better understanding of maturation process of animal manure compost. 相似文献
646.
Kim KY Jong Ko H Tae Kim H Shin Kim Y Man Roh Y Min Lee C Nyon Kim C 《Journal of environmental management》2008,88(2):195-202
The aim of this field study was to determine the concentrations and emissions of ammonia and hydrogen sulfide in different types of pig buildings in Korea to allow objective comparison between pig housing types in Korea and other countries. Concentrations of ammonia and hydrogen sulfide in the pig buildings averaged 7.5ppm and 286.5ppb and ranged from 0.8 to 21.4ppm and from 45.8 to 1235ppb, respectively. The mean emissions of ammonia and hydrogen sulfide per pig (normalized to 75kg liveweight) and area (m2) from pig buildings were 250.2 and 37.8mg/h/pig and 336.3 and 50.9mg/h/m2, respectively. Ammonia and hydrogen sulfide concentrations and emissions were higher in the pig buildings managed with deep-pit manure systems with slats and mechanical ventilation than in other housing types. 相似文献
647.
The effects of hydroxyapatite (HAP) on dechlorination of tetrachloroethylene (PCE) by zero-valent zinc (ZVZ) were examined in batch systems. PCE was primarily transformed to trichloroethylene by ZVZ, with 1,2-trans-dichloroethylene representing a minor product. Dechlorination of PCE was accelerated by the presence of HAP, and the pseudo-first order rate constants increased with increasing amount of HAP. Zn(II), mostly generated from oxidative dissolution of ZVZ by PCE, was effectively removed from the solution by HAP. Ion substitution, coprecipitation, and adsorption are proposed as the possible mechanisms for Zn(II) removal. These reactions appeared to occur simultaneously and the contribution of each reaction to overall removal of Zn(II) was primarily dependent on HAP loading at constant ZVZ loading. The results indicate that the use of HAP in combination with conventional zero-valent metals is promising in that it can achieve both degradation of organic contaminants and stabilization of inorganic contaminants. 相似文献
648.
649.
Lee Young Su Kim Young Kwon Choi Eunhwa Jo Hyeri Hyun Hyeseung Yi Seung-Muk Kim Jae Young 《Environmental science and pollution research international》2022,29(44):66591-66604
Environmental Science and Pollution Research - The emission sources and their health risks of fine particulate matter (PM2.5) in Siheung, Republic of Korea, were investigated as a middle-sized... 相似文献
650.
Hong Myung Hwan Joo So Young Kim Dong Wook Yoon Jin-Ho 《Journal of Material Cycles and Waste Management》2022,24(1):63-72
Journal of Material Cycles and Waste Management - Owing to the increasing ACW generation, asbestos detoxification and recycling technologies are required for environmental and economic reasons.... 相似文献