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991.
In 2000, 63 (polished) white rice samples were collected in eight administrative areas all over South Korea and analyzed for
16 elements by inductively coupled plasma atomic emission spectrometry (ICP-AES). Potassium had the highest content, next
to Mg, Ca, Si, Zn, Na, Al and Fe. Most of the samples contained worldwide average concentrations of essential and trace elements
in rice grains reported by various researches. For inter-area differences in those elements in the rice, the statistical analysis
showed no significant differences (p > 0.05) among the eight administrative areas, suggesting that inter-area differences were not substantial in most cases.
Thus, the present data can be used as national background levels of elements in rice produced in South Korea. Using the published
data on daily consumption of rice in South Korea, it was possible to estimate the daily intake of As, Cd, Cu, Pb and Zn via
rice. The results showed that a regular consumption of rice produced in Korea plays an important role in accumulation of essential
and trace elements in Korean, especially for farm-households consuming relatively large amounts of rice. 相似文献
992.
Freitas MC Farinha MM Ventura MG Almeida SM Reis MA Pacheco AM 《Environmental monitoring and assessment》2005,109(1-3):81-95
This paper describes concentration amounts of arsenic (As), particulate mercury (Hg), nickel (Ni) and lead (Pb) in PM10 and PM2.5, collected since 1993 by the Technological and Nuclear Institute (ITN) at different locations in mainland Portugal, featuring
urban, industrial and rural environments, and a control as well. Most results were obtained in the vicinity of coal- and oil-fired
power plants. Airborne mass concentrations were determined by gravimetry. As and Hg concentrations were obtained through instrumental
neutron activation analysis (INAA), and Ni and Pb concentrations through proton-induced X-ray emission (PIXE). Comparison
with the EU (European Union) and the US EPA (United States Environmental Protection Agency) directives for Ambient Air has
been carried out, even though the sampling protocols herein – set within the framework of ITN's R&D projects and/or monitoring
contracts – were not consistent with the former regulations. Taking this into account, 1) the EU daily limit for PM10 was exceeded a few times in all sites except the control, even if the number of times was still inferior to the allowed one;
2) the EU annual mean for PM10 was exceeded at one site; 3) the EPA daily limit for PM2.5 was exceeded one time at three sites; 4) the EPA annual mean for PM2.5 was exceeded at most sites; 5) the inner-Lisboa site approached or exceeded the legislated PMs; 6) Pb levels stayed far below
the EU limit value; and 7) concentrations of As, Ni and Hg were also far less than the reference values adopted by EU. In
every location, Ni appeared more concentrated in PM2.5 than in coarser particles, and its levels were not that different from site to site, excluding the control. The highest As
and Hg concentrations were found in the neighbourhood of the coal-fired, utility power plants. The results may be viewed as
a “worst-case scenario” of atmospheric pollution, since they have been obtained in busy urban-industrial areas and/or near
major power-generation and waste-incineration facilities. 相似文献
993.
994.
稀土元素在水体食物链生物中迁移的摸拟研究 总被引:3,自引:1,他引:3
本文用动态和静态摸拟系统分别研究了稀土元素在小球藻-大型溞-鲤鱼食物链生物上的迁移。结果表明:水生生物对稀土的生物积累作用有从水体直接摄取和从食物间接摄取两种方式,但稀土元素在该食物链上无生物放大作用,生物体中积累的稀土量和水环境中残余的稀土浓度从轻稀土向重稀土递减,稀土元素在水环境中迁移的最重要形式可能是物理-化学迁移。 相似文献
995.
贵州省原煤中微量元素的组成特征 总被引:10,自引:0,他引:10
研究了贵州省各主要煤田中主要采煤层的As,B,Ba,Be,Cd,Co,Cr,C,Hg,Li,Ni,Pb,Sb,Se,Sr,Tl,V,Zn等微量元素的组成特征,贵州省原煤中微量元素的含量总体上的世界范围内的一致,但Sb,As,Hg等有害元素则明显富集,由于煤炭成因上的特殊性,其微量元素的组成除受煤植物的影响外,后期在煤作用对其有决定性的影响。 相似文献
996.
997.
Urban geochemistry: A study of element distributions in the soils of tallinn (Estonia) 总被引:17,自引:0,他引:17
First results are presented from the Urban geochemistry of Tallinn, a project supported by the Scientific and Environmental Affairs Division of NATO. The distribution of chemical elements in 532 samples of the topsoils from the territory of the biggest industrial centre of Estonia (pop. 500,000) is interpreted. Statistical analysis and mapping of major and trace elements at the territory of the Tallinn region and of the city were performed and background values and local anomalies of chemical elements on the territory were determined. The investigation focussed on the determination of zones with anomalously high concentrations of elements and the relationships of soil contamination with different pollution sources. The increase of the element concentrations has natural as well as anthropogenic origins. A detailed comparative analysis of the element distributions and the results of a factor analysis showed that the distribution of the major chemical elements depended mainly on the composition of the underlying sedimentary rocks.The territory of Tallinn is characterised by relatively high and widespread concentrations of Ba, Cr, Ga, Ni, Ti and Zn. Especially intensive local concentrations were determined for As, Cr, Mn, Ni, Pb, S, V and Zn, which are typical for the local pollution of the soils by industrial sources. The levels of As, Cr, Mn and V are more than three times. Pb and Zn are more than five times higher in the geochemical anomalies than for background levels. For the Tallinn region two major associations of elements connected with industrial pollutions of the soil are typical: the first association includes Ba, Cr, Mn, Ni and partly Fe and the second one includes As, Pb and Zn. For the city of Tallinn an increase of Ag, Ba, Be, La, Pb, Sn and Zn concentration in the soil was detected. Ba, Cr, Mn and Ni occur in high concentrations in the soils around Maardu. Different types of contamination sources can be identified in Tallinn and its suburbs. 相似文献
998.
Eight selected elements (As, Cd, Co, Cu, Pb, Zn, Cr and Ni) were determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES) in five samples from the tailings pond (Zbiornik Gilow) and waste water stream (Zimmica) in the Kupferschiefer mining district in Southwest Poland. Waste water from mining and concentration plants was discharged into Zbiornik Gilow pond for 30 years before 1989. Below Zbiornik Gilow the water flows through Zimmica stream, and then discharges into the River Odra. The analytic results indicate that the contamination of As, Cd, Co, Cu, Pb and Zn has spread out over 5km, and the contamination by Ni and Cr extends for 1.5km along the Zimmica stream although the stream has been abandoned since 1989. These elements could still be toxic for plants, animals and humans. Polycyclic aromatic hydrocarbons (PAHs) were determined by GC and GC/MS. The results of the sediment samples show a contamination of PAHs only in trace contents. 相似文献
999.
报道了乌鲁木齐市一年的内大气TSP中28种元素含量的监测结果,污染程度及变化规律,为进一步加强环境管理和大气污染治理,改善环境质量提供科学依据。 相似文献
1000.
采用常规酸消化方法分解锑渣和铋渣固体废弃物试样.处理后的消解液直接用ICP—AES法同时测定了Cu、Ph、Mn、Cr、Ni、和Zn等多种重金属元素。方法的精密度和准确度较好,适合于常规固体环境样品的分析。 相似文献