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691.
青藏高原冰川雪坑中离子浓度的区域特征及来源分析 总被引:3,自引:1,他引:3
研究了青藏高原古仁河口冰川、小冬克玛底冰川和玉珠峰冰川中的离子浓度特征. 使用离子色谱对这3条冰川雪坑中的样品进行了分析,并运用相关分析法探讨了离子的主要来源. 结果表明,Ca2+、Mg2+、Na+、Cl-和SO2-4的浓度从古仁河口冰川、小冬克玛底冰川到玉珠峰冰川依次升高,即从高原南部到北部依次升高. 反映了从青藏高原的南部到北部,陆源物质成分所占比重越来越大的特征. 玉珠峰冰川中Cl-、Na+和SO2-4浓度比古仁河口冰川和小冬克玛底冰川高几倍,可能是由于玉珠峰冰川北侧柴达木盆地盐湖的蒸发及盐类矿物风化的结果. NO-3、K+ 和NH+4的来源比较复杂,对环境的指示意义不够显著. 相似文献
692.
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694.
泾河支流地表水地下水的水化学特征及其控制因素 总被引:1,自引:16,他引:1
为研究泾河支流(黑河流域)的水化学特征及其控制因素,2014~2015年先后采集枯水期及汛期地表水和地下水的水样242个,综合运用Piper三线图、相关性分析和Gibbs图等方法,分析了黑河流域水化学特征,并探讨了黑河流域的水化学演化规律.结果表明,研究区水体均呈弱碱性,2014年枯水期地表水和地下水阳离子以Na+为主,分别约占阳离子总量的56%和58%;阴离子以SO_4~(2-)为主,分别约占地表水和地下水阴离子总量的33%和39%;其它3个时期主要地表水和地下水组成阴阳离子均以HCO_3~-和Na~+为主,约占阴离子和阳离子总量的44%~46%和42%~56%.枯水期地表水TDS在上中游波动较大,汛期地表水和地下水的TDS由上游到下游沿河道逐渐增加.由枯水期到汛期,地表水的水化学类型由Na-Mg-Cl-SO4型转变为Ca-Mg-HCO3型,地下水由Mg-Cl-SO_4型转变为Ca-Na-HCO_3型.水化学样品点大部分分布在Gibbs图左中上部,说明流域水化学离子形成主要受岩石风化和蒸发-浓缩作用的影响,而人类活动对水化学的影响在枯水期较汛期更显著. 相似文献
695.
Xi Cheng Hong Li Yujie Zhang Yuping Li Weiqi Zhang Xuezhong Wang Fang Bi Hao Zhang Jian Gao Fahe Chai Xiaoxiu Lun Yizhen Chen Jian Gao Junyi Lv 《环境科学学报(英文版)》2018,30(9):150-167
Continuous observation of isoprene, α-pinene and β-pinene was carried out in a typical urban area of Beijing from March 2014 to February 2015, using an AirmoV OC online analyzer. Based on the analysis of the ambient level and variation characteristics of isoprene, α-pinene and β-pinene, the chemical reactivity was studied, and their sources were identified. Results showed that the concentrations of isoprene, α-pinene and β-pinene in the urban area of Beijing were lower than those in richly vegetated areas; the concentrations of isoprene were at a moderate level compared with those of previous studies of Beijing. Concentrations of isoprene, α-pinene and β-pinene showed different seasonal, monthly, daily and diurnal variations, and all of the three species showed higher level at night than those in the daytime as a whole, the variations of isoprene, α-pinene and β-pinene mainly influenced by emission of sources, photochemical reaction, and meteorological parameters. Isoprene was the largest contributor to the total OFP values than α-pinene and β-pinene. α-Pinene was the largest contributor to the total SOAFP values than isoprene and β-pinene in autumn, while isoprene was the largest one in other seasons. Isoprene, α-pinene and β-pinene were derived mainly from biological sources; and α-pinene level were also affected by industrial sources. To reduce the concentrations of isoprene, α-pinene and β-pinene, it is necessary to scientifically select urban green plant species, and more strict control measures should be taken to reduce the emission of α-pinene from industrial sources, such as artificial flavors and resins synthesis processes. 相似文献
696.
涪陵页岩气田一期工程环境影响调查 总被引:1,自引:0,他引:1
采用现场调研与实地监测相结合的方法对涪陵页岩气田一期工程污染源和区域环境质量现状进行深入调查研究,剖析涪陵页岩气开发对环境产生的影响。结果表明,涪陵页岩气田开发过程中废水实行循环利用,钻屑固体废物固化填埋,企业环保措施基本落实,短期内页岩气开发未对区域环境产生明显不良影响。指出修建井场、池体、道路等设施对生态环境具有一定影响,且随着时间推移,钻屑固化填埋对周围土壤及水环境也具有潜在影响。 相似文献
697.
Paul D. Jensen Lauren BassonEmma E. Hellawell Malcolm R. Bailey Matthew Leach 《Resources, Conservation and Recycling》2011,55(7):703-712
Geographic proximity is said to be a key characteristic of the resource reuse and recycling practice known as industrial symbiosis. To date, however, proximity of symbiont companies has remained an abstract characteristic. By conducting a statistical analysis of synergies facilitated by the United Kingdom's National Industrial Symbiosis Programme during their first five years of operation, this article attempts to quantify geographic proximity and in the process provide practitioners with an insight into the movement trends of different waste streams. Among other it was found that the median distance materials travelled within a symbiotic relationship is 20.4 miles. It is argued that quantitative information of this form is of practical value for the effective deployment of industrial symbiosis practitioners and wider resource efficiency planning. The results and discussion presented within this article are specific to industrial symbiosis opportunities facilitated within the United Kingdom; the methodology and assessment of resource movement influences are, however, expected to be relevant to all countries in which industrial activity is similarly mature and diversified. 相似文献
698.
699.
Perrino C Canepari S Cardarelli E Catrambone M Sargolini T 《Environmental monitoring and assessment》2008,136(1-3):69-86
A field study was carried out at six locations in the Lazio region (Central Italy) aimed at characterising atmospheric particulate
matter (PM10 and PM2.5) from the point of view of the chemical composition and grain size distribution of the particles, the mixing properties of
the atmosphere, the frequency and relevance of natural events. The combination of four different analytical techniques (ion
chromatography, X-ray fluorescence and ICP for inorganic components, thermo-optical analysis for carbon compounds) yielded
sound results in terms of characterisation of the air masses. During the first three months of the study (October–December
2004), many pollution events of natural (sea-salt or desert dust episodes) or anthropogenic nature were identified and characterised.
More than 90% of the collected mass was identified by chemical analysis. The central role played by the mixing properties
of the lower atmosphere when pollution events occurred was highlighted. The results show a major impact of primary anthropogenic
pollutants on traffic stations and a homogeneous distribution of secondary pollutants over the regional area. An evaluation
of the sources of PM and an identification of possible reliable tracers were obtained using a chemical fractionation procedure. 相似文献
700.
Subba Rao N 《Environmental monitoring and assessment》2008,136(1-3):437-447
Trace elements are essential for human health. However, excess concentrations of these elements cause health disorders. A
study has been carried out in Visakhapatnam environs, Andhra Pradesh, India to ascertain the causes for the origin and distribution
of iron content in the groundwaters. Fifty groundwater samples are collected and analyzed for iron. The content of iron ranges
from 400 to 780 μg/l. A comparison of groundwater data with rock and soil chemistry suggests that the concentration of iron
(400–530 μg/l) in the groundwaters is derived from the rocks and soils due to geogenic processes. This concentration is taken
as a natural occurrence of iron in the groundwaters of the study area for assessing the causes for its next higher content
(>530 μg/l). Relatively higher concentration of iron (540–550 μg/l) is observed at some well waters, where the wells are located
nearby municipal wastewaters, while the very high concentration of iron (610–780 μg/l) is observed in the industrially polluted
groundwater zones, indicating the impact of anthropogenic activities on the groundwater system. These activities mask the
concentration of iron caused by geogenic origin. Hence, both the geogenic and anthropogenic activities degrade the groundwater
quality. Drinking water standards indicate that the iron content in all the groundwater samples exceeds the permissible limit
(300 μg/l) recommended for drinking purpose, causing the health disorders. Necessity of close monitoring of groundwater quality
for assessing the impact of geogenic and anthropogenic sources with reference to land use/land cover activities is emphasized
in the present study area to protect the groundwater resources from the pollution. 相似文献