全文获取类型
收费全文 | 445篇 |
免费 | 27篇 |
国内免费 | 214篇 |
专业分类
安全科学 | 36篇 |
废物处理 | 35篇 |
环保管理 | 38篇 |
综合类 | 266篇 |
基础理论 | 85篇 |
污染及防治 | 159篇 |
评价与监测 | 25篇 |
社会与环境 | 18篇 |
灾害及防治 | 24篇 |
出版年
2023年 | 15篇 |
2022年 | 17篇 |
2021年 | 20篇 |
2020年 | 22篇 |
2019年 | 20篇 |
2018年 | 24篇 |
2017年 | 24篇 |
2016年 | 26篇 |
2015年 | 42篇 |
2014年 | 37篇 |
2013年 | 54篇 |
2012年 | 50篇 |
2011年 | 38篇 |
2010年 | 33篇 |
2009年 | 29篇 |
2008年 | 26篇 |
2007年 | 39篇 |
2006年 | 17篇 |
2005年 | 16篇 |
2004年 | 10篇 |
2003年 | 13篇 |
2002年 | 20篇 |
2001年 | 8篇 |
2000年 | 10篇 |
1999年 | 17篇 |
1998年 | 8篇 |
1997年 | 6篇 |
1996年 | 8篇 |
1995年 | 10篇 |
1994年 | 6篇 |
1993年 | 8篇 |
1992年 | 7篇 |
1991年 | 1篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1981年 | 2篇 |
排序方式: 共有686条查询结果,搜索用时 843 毫秒
121.
Occurrence, sources, and inventory of hexabromocyclododecanes (HBCDs) in soils from Chongming Island, the Yangtze River Delta (YRD) 总被引:6,自引:0,他引:6
Hexabromocyclododecanes (HBCDs) is a concern due to their large usage combining with physico-chemical properties and toxicity to wildlife and human. However, very limited data were reported on HBCDs in soils, especially from rural area. In this study, 22 soil samples were collected from Chongming Island at estuary of the Yangtze River Delta, to investigate the level, diasteroisomer profile, potential sources, and mass inventory of HBCDs. The total concentrations ranged from not detected to 93.8 pg g−1 dry weight (dw) with a mean of 23.3 pg g−1 dw, which was at the low end of the global levels. The wide distribution of HBCDs in soils suggested that the local emissions of HBCD-containing materials and/or the inputs via atmospheric transport from other regions were two possible sources. Variation of HBCDs levels was observed in different types of soils. Woodland, tideland and road soils contained slightly higher HBCDs than those of farmland and grassland. Overall, γ-HBCD was the dominant diasteroisomer in soils, followed by α-HBCD and β-HBCD. Significant but weak correlations were only found between α-HBCD and β-HBCD versus TOC content in soils. Currently, the mass inventory of HBCDs in soils of Chongming Island was 5.3 kg. Based on these data, we gave perspective on human intake of HBCDs via soil ingestion by age. Local resident’s intakes ranged from 15.5 to 97.8 fg kg body weight−1 d−1, in which children are exposed more than adults. 相似文献
122.
123.
大连石化公司运用标准化法对该厂污染源进行了普查,进而对污染源做出了评价。以二蒸馏装置为例,对总排放口污染源的监测数据进行了标化处理,确定了主要的污染因子及污染源:石油类主要来自减压塔顶分离器;硫化物主要来自减压塔顶油、水分离器和常压塔顶油、水分离器;挥发酚主要来自减压塔顶油、水分离器。 相似文献
124.
中国环境基准研究重点方向探讨 总被引:6,自引:1,他引:6
环境基准是环境标准的科学依据,在国家环境质量评价和风险管理体系中处于基础地位。它主要是依据特定对象在环境介质中的暴露数据,以及与环境要素的剂量效应关系数据,通过科学判断得出的,涉及环境化学、毒理学、生态学、流行病学、生物学和风险评估等前沿学科领域。国家环境基准研究是一个长期的系统工程,本文基于环境基准研究的学科特点和国际前沿,结合国家科技需求和相关领域的研究现状,综合分析并提出了未来中国环境基准研究的重点研究方向:1)环境基准的理论与方法学;2)环境基准基础数据库;3)基准目标污染物的筛选甄别和优先排序技术;4)水体营养物基准;5)生物测试与毒性评价技术;6)人体暴露评价理论与相关技术;7)环境基准的审核和校对;8)环境基准与标准转化理论及其对环境管理支撑技术。本文从环境基准学科发展的角度,阐述了与环境基准研究紧密相关的8个重点研究方面的国内外研究进展、关键科学问题以及未来重点研究内容。同时指出,这些重要的研究方向是环境基准研究的根本,未来环境基准的长期战略发展必将是建立在各个重要方向长足发展的基础之上,环境基准研究也必带动这些方向的共同蓬勃发展,为环境地球化学、毒理学、生态学等学科领域发展注入活力。 相似文献
125.
利用1961年-2012年阿勒泰地区气象观测资料,对雾的时空分布特征和变化趋势进行分析。结果表明:阿勒泰地区雾日数在时间分布上,初春的3月出现最多;冬季(12月-翌年2月)雾出现的比例最高,占37.6%。20世纪80年代年雾出现日数最多,2000年至今最少。阿勒泰地区雾日数在空间分布上也不是很均匀,区域性为西部的吉木乃、哈巴河县最多,东部的富蕴、青河县最少。阿勒泰地区雾出现日数年变化率与各县站的变化趋势一致,均呈明显的下降趋势,在1966年出现了减少的突变现象。R/S方法分析表明,各县站未来的年雾出现日数仍会呈减少趋势,雾天对人体有一定的影响。 相似文献
126.
兰州城区大气粒子态汞的污染状况 总被引:8,自引:0,他引:8
通过调查发现在市工业区,粒子态汞浓度高,冬,夏平均值为0.91和1.00ng/m^3,最高达1.92ng/m^3,冬夏季无显著性差异,秋季浓度低,交通频繁区和交通商业混合区冬季平均值0.45ng/m^3,夏季0.49ng/m^3在清洁区大部分在0.10ng/m^3左右,最低0.070ng/m^3,显示夏季和城区粒子态汞浓度偏高的特征。工业区粒子态汞主要是由人为污染产生的气态汞吸附在同一污染源的粒尘 相似文献
127.
Source apportionment of polycyclic aromatic hydrocarbons in surface soil in Tianjin, China 总被引:15,自引:0,他引:15
Zuo Q Duan YH Yang Y Wang XJ Tao S 《Environmental pollution (Barking, Essex : 1987)》2007,147(2):303-310
Principal component analysis and multiple linear regression were applied to apportion sources of polycyclic aromatic hydrocarbons (PAHs) in surface soils of Tianjin, China based on the measured PAH concentrations of 188 surface soil samples. Four principal components were identified representing coal combustion, petroleum, coke oven plus biomass burning, and chemical industry discharge, respectively. The contributions of major sources were quantified as 41% from coal, 20% from petroleum, and 39% from coking and biomass, which are compatible with PAH emissions estimated based on fuel consumption and emission factors. When the study area was divided into three zones with distinctive differences in soil PAH concentration and profile, different source features were unveiled. For the industrialized Tanggu-Hangu zone, the major contributors were cooking (43%), coal (37%) and vehicle exhaust (20%). In rural area, however, in addition to the three main sources, biomass burning was also important (13%). In urban-suburban zone, incineration accounted for one fourth of the total. 相似文献
128.
The ageing effect on the bioaccessibility and fractionation of arsenic in soils from China 总被引:7,自引:0,他引:7
Ingestion of contaminated soil has been recognized as an important exposure pathway of arsenic for humans, especially for children through outdoor hand-to-mouth activities. An improved sequential extraction procedure was employed in an attempt to reveal the relationship between bioaccessibility and fractionation of As in five soils from China. Arsenic bioaccessibility in acidic ( approximately pH 4.5) soils reached approximately stable levels after a sharp decline within one week of ageing. In contrast, As bioaccessibility in higher pH (>6.0) soils was found to be significantly higher and took two weeks of ageing to reach stable levels. The artificially added As was more labile than indigenous As. The main proportions of added As were found in the specifically sorbed and amorphous and poorly-crystalline hydrous Fe/Al oxide-bound fractions. Correlation analysis shows that the non-specifically and specifically sorbed As are likely to constitute the main proportion of bioaccessible soil As. The soil content of amorphous and crystalline Fe/Al oxides and soil pH appear to be the key factors controlling, not only the time needed to reach a steady state, but also the magnitude of the bioaccessibility of As added to the soils. 相似文献
129.
建立潜流湿地有机污染物迁移转化模型,采用多孔介质模型描述潜流湿地的水力特性,并引入Monod方程相耦合,实现对湿地系统内部流场及水质浓度的同时模拟。通过实验,校核模型参数,并验证模型。结果表明,该模型能较好模拟潜流湿地中有机污染物的去除效果;计算条件下,在不同基质填料的潜流湿地中都会出现滞水区和快速通道,影响水力效率与污染物去除效果;预测了不同填料系统中7种典型选控性有机污染物的去除效果,其处理效率:苯胺苯酚二甲苯甲苯苯硝基苯氯苯,可通过优选填料提高吸附量和延长停留时间来提高选控性有机物的处理效果。 相似文献
130.
Seasonal variation on size distribution and concentration of PAHs in Guangzhou city, China 总被引:6,自引:0,他引:6
Size distribution aerosol samples were collected at an urban location of Guangzhou in four seasons of 2003-2004 by a MOUDI (Micro-orifice Uniform Deposit Impactor). The particle loading (PM10: 80-397 microg m(-3)) was comparable with some other Asia cities; however, much higher than that of Western Europe and North America. Polycyclic aromatic hydrocarbons (PAHs) were measured by gas chromatography with mass selective detector (GC-MS). Seasonal effects on the size distribution of PAHs are presented. Bimode (accumulation and coarse mode) and unimode (accumulation mode) distributions were observed for low-molecule-weight and high-molecule-weight PAHs. A slight shift to larger particles was found for the accumulation mode in autumn and winter, compared with that of spring and summer. One explanation is that the longer aging process of PAHs in autumn and winter would result in volatilization from finer particles followed by condensation onto coarser particles. Another is there was mixing process of local emission with long-range transported aerosol in autumn and winter. The relative higher value of IcdP/(BghiP+IcdP) and lower value of BghiP/BeP in winter also give evidences to the mixing process. The level of PAHs concentration has been much elevated in recent years. This can be attributed to the fast growth of motor vehicle and energy consumption. 相似文献