全文获取类型
收费全文 | 14806篇 |
免费 | 498篇 |
国内免费 | 1746篇 |
专业分类
安全科学 | 400篇 |
废物处理 | 970篇 |
环保管理 | 1656篇 |
综合类 | 4551篇 |
基础理论 | 4040篇 |
污染及防治 | 2620篇 |
评价与监测 | 1389篇 |
社会与环境 | 1229篇 |
灾害及防治 | 195篇 |
出版年
2024年 | 29篇 |
2023年 | 106篇 |
2022年 | 317篇 |
2021年 | 286篇 |
2020年 | 312篇 |
2019年 | 234篇 |
2018年 | 1689篇 |
2017年 | 1633篇 |
2016年 | 1465篇 |
2015年 | 467篇 |
2014年 | 422篇 |
2013年 | 481篇 |
2012年 | 918篇 |
2011年 | 1828篇 |
2010年 | 1135篇 |
2009年 | 1015篇 |
2008年 | 1242篇 |
2007年 | 1556篇 |
2006年 | 327篇 |
2005年 | 236篇 |
2004年 | 160篇 |
2003年 | 211篇 |
2002年 | 240篇 |
2001年 | 139篇 |
2000年 | 126篇 |
1999年 | 95篇 |
1998年 | 72篇 |
1997年 | 47篇 |
1996年 | 51篇 |
1995年 | 42篇 |
1994年 | 40篇 |
1993年 | 37篇 |
1992年 | 21篇 |
1991年 | 10篇 |
1990年 | 9篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 1篇 |
1984年 | 12篇 |
1983年 | 10篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1973年 | 1篇 |
1935年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
801.
金属冶炼烟气中的砷大都以颗粒物的形式存在,对环境造成污染.2010年,国家颁布了《铜、镍、钴工业污染物排放标准》( GB 25467-2010),对于废气中砷的监测,该标准中规定使用《空气和废气砷的测定 二乙基二硫代氨基甲酸银分光光度法(暂行)》( HJ 540-2009).然而该方法中对于烟气中砷的监测方法存在一定问题,高氯酸在高温消解过程中易爆炸,比较危险,另外采用在锥形瓶内加热至产生白烟的排酸方式不能有效地排净硝酸,会导致反应无法进行.为此,就该方法中有组织排放废气中砷的前处理部分提出了改进意见. 相似文献
802.
803.
根据实验室资质认定对于方法确认的要求,结合环境监测实验室的特点,提出了新项目方法确认的具体步骤,并分析了其中存在的常见问题。指出在方法确认过程中,应严格按照标准方法和监测技术规范进行全过程试验,尤其不能忽视采样现场实验、空白实验和检出限的测定。建议在精密度与准确度检验过程中,使用高、中、低不同浓度的有证标准样品,实际样品加标回收,比对试验(方法比对、人员比对、实验室间比对),增加分析次数等多种手段,确保新项目开展的可靠性。 相似文献
804.
805.
Sotiria Anastasiou Georgios K. Sylaios Vassilios A. Tsihrintzis 《Environmental monitoring and assessment》2015,187(6):392
The present study investigates the use of combined methods of optical and acoustic sensors, in collaboration with direct in situ measurements, for the calibration and validation of a model transforming acoustic backscatter intensity series into suspended particulate matter (SPM) concentration datasets. The model follows previously elaborated techniques, placing particular attention to the parameterization of the acoustic absorption index as a function of water physical properties. Results were obtained from the annual deployment (during 2007–2008) of an upward-facing acoustic Doppler current profiler (ADCP) (307 kHz), equipped with a Wave Array, and an optical backscatter sensor (OBS), at the bottom of Thassos Passage near Nestos River plume (Thracian Sea, Northern Greece). The OBS was calibrated through linear regression, using 2007 and 2012 field sampling data, exhibiting an error of 13–14 % due to chlorophyll presence. The ADCP signal was calibrated through simultaneous measurements of backscatter intensity and turbidity profiles. Harmonic analysis on the model-produced SPM concentrations explained the tidal influence on their variability, especially during the summer. Empirical orthogonal functions analysis revealed the impact of waves and wave-induced currents on SPM variability. Finally, Nestos River sediment load was found uncorrelated to the SPM change in Thassos Passage, due to the dispersal and sediment deposition near the river mouth. 相似文献
806.
Ruzica Micic Snezana Mitic Biljana Arsic Anja Jokic Milan Mitic Danijela Kostic Aleksandra Pavlovic Milan Cekerevac Ljiljana Nikolic-Bujanovic Zaklina Spalevic 《Environmental monitoring and assessment》2015,187(6):389
Zinc, copper, iron, chromium and cobalt are essential elements for human health, showing toxicity only in high concentrations, while lead and cadmium are extremely toxic even as traces. Therefore, it is important to monitor the contents of toxic metals in vegetables. Large number of vegetables is grown and used in nutrition, in Kosovo. The concentrations of selected elements in vegetables (radish, onion, garlic and spinach) from Kosovo were determined using ICP-OES method. Oral intake of metals and health risk index were calculated. Statistical analysis indicated numerous positive correlations between concentrations of selected elements in vegetables. As a result of principal component analysis, 15 new variables were obtained which were characterized by eigenvalues. The sequence of health quotients for the heavy metals followed the decreasing order Zn?=?Mn?>?Pb?>?Cu?>?Ni?>?Fe?>?Cd?>?Co?>?Cr. The health quotients for all investigated heavy metals were below 1 (one), which is considered safe. The vegetables from Kosovo are mainly safe for use in everyday diet. 相似文献
807.
Thomas Minning Darren A. Lytle Maily Pham Keith Kelty 《Environmental monitoring and assessment》2015,187(6):383
Distinguishing between soluble and particulate lead in drinking water is useful in understanding the mechanism of lead release and identifying remedial action. Typically, particulate lead is defined as the amount of lead removed by a 0.45-μm filter. Unfortunately, there is little guidance regarding selection of filter membrane material and little consideration to the possibility of the sorption of dissolved lead to the filter. The objective of this work was to examine the tendency of 0.45-μm syringe filter materials to adsorb lead. Tests were performed with water containing 40 and 24 μg/L soluble lead at pH 7 buffered with 50 mg C/L dissolved inorganic concentration (DIC). The amounts of lead sorbed greatly varied by filter, and only two filter types, polypropylene and mixed cellulose esters, performed well and are recommended. Great care must be taken in choosing a filter when filtering soluble lead and interpreting filter results. 相似文献
808.
V. Vijayasree Hebsy Bai S. Naseema Beevi Thomas Biju Mathew Thomas George George Xavier 《Environmental monitoring and assessment》2015,187(5):299
Dissipation and decontamination of chlorantraniliprole (Coragen 18.5 SC) in brinjal and okra fruits were studied following field application at single and double doses of 30 and 60 g ai ha?1, and the residues of the insecticide was estimated using LC-MS/MS. Initial residues of chlorantraniliprole at single and double doses on the fruits of brinjal were 0.72 and 1.48 mg kg?1, while on okra fruits, the residues were 0.48 and 0.91 mg kg?1, respectively. The residues reached below detectable level of 0.01 mg kg?1 on the 10th day. Half-life of chlorantraniliprole at 30 and 60 g ai ha?1 on brinjal was 1.58 and 1.80 days with the calculated waiting period of 0.69 and 2.38 days, whereas on okra, the values were 1.60 and 1.70 and 0 and 1.20 days, respectively. The extent of removal of chlorantraniliprole using simple decontaminating techniques at 2 h and 3 days after spraying was 40.99–91.37 % and 29.85–89.12 %, respectively, from brinjal fruits and 47.78–86.10 % and 41.77–86.48 %, respectively, from okra fruits. 相似文献
809.
The dynamic and residues of florasulam and flumetsulam in corn field ecosystem were investigated using quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The limits of quantification (LOQs) of the proposed method ranged from 0.005 to 0.01 mg/kg. Mean recoveries and relative standard deviations (RSDs) of the two compounds in all samples at three spiking levels ranged 94–110 % and 2.0–9.2 %, respectively. Florasulam and flumetsulam degradation followed first-order kinetics with half-lives 1.7–2.9 and 3.3–8.7 days in soil and 1.3–1.8 and 0.9–1.7 days in plant, respectively. The residues in all the samples were found to be less than the LOQs at preharvest intervals of 53 and 78 days. The results suggest that the combined use of florasulam and flumetsulam on corn is considered to be safe under the recommended conditions and can be utilized for establishing the maximum residue limit (MRL) of florasulam in corn in China. 相似文献
810.
本方法针对土壤中挥发性芳香烃顶空前处理条件进行了研究,优化了顶空密封垫的选择、顶空平衡温度、加热平衡时间、进样时间和顶空瓶压力等顶空前处理条件,测定条件科学、准确,完全能够满足土壤中挥发性芳香烃监测分析的灵敏度和准确度相关的技术要求。该方法精密度为1.7%~9.8%,准确度为34.3%~83.7%,检出限为2.0~4.2μg/kg。为制订土壤中挥发性芳香烃监测分析方法提供了技术支持。 相似文献