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571.
572.
Transfer rate of pesticide residues from medicinal plants in different types of extractive solutions
Alexandru Mihai Florea Veronica Drumea Roxana Andreea Nita Adelina Bicu Laura Olariu Ligia Elena Dutu 《毒物与环境化学》2020,102(1-4):37-61
AbstractStarting from the suspicion that the medicinal herbs may contain traces of pesticides and taking into account the risks of patients being exposed to contaminated products, the aim of this research was to evaluate the pesticide residues and the degree of their transfer (%) in three types of preparations (infusion, decoctionand cold maceration), for four medicinal plant species very often used in phytotherapy (Rosmarini folium, Menthae folium, Saturejae herba and Basilica herba). For each type of plant product, four samples were purchased from different manufacturers and they have been analyzed using gas chromatography- tandem mass spectrometry. One out of four samples of the same plant species contain at least one pesticide residue above the maximum level and shows a significant transfer of these residues in aqueous extractive solutions during extraction. The highest rate of pesticide transfer from medicinal plants was identified in infusions, recommended by many manufacturers. 相似文献
573.
采用联用技术测定中国海产品中砷的形态 总被引:7,自引:0,他引:7
1 IntroductionAtthebeginningof2 0 thcentury ,highlevelsofarsenic~mg·kg-1 werefoundinmarineorga nisms,whichattractedalotofattention ,becausearsenicisoneofthemostnotoriouselementsonaccountofitshumantoxicity.Forthisreason ,thedeterminationofthetotalamount… 相似文献
574.
PCDTs in the environment 总被引:3,自引:0,他引:3
Seija Sinkkonen 《Chemosphere》1997,34(12):2585-2594
Polychlorinated dibenzothiophenes (PCDTs) are sulfur analogues of polychlorinated dibenzofurans. Recently, PCDTs have been found in stack gas and fly ash samples, pulp mill effluents, sediments and in some aquatic organisms. PCDTs have been analyzed by high resolution GC/MS and by other GC-MS techniques. Combustion is until now the major known source of PCDTs in the environment. Tri-, tetra- and pentaCDTs in concentrations approaching those of PCDTs have been analyzed in some samples from waste incineration and metal reclamation. Concentrations of PCDTs in pulp mill effluents have been found to be quite low. 2378-TeCDT was found to be the major TeCDT isomer in some pulp mill effluents. Preliminary toxicological investigations have shown that PCDTs possess some kind of dioxin type toxicity. 相似文献
575.
Paasivirta J Kukkola J Knuutinen J Pessala P Schultz E Herve S 《Environmental science and pollution research international》2005,12(6):375-380
Background, Aim and Scope At present, large-scale paper manufacture involves delignification and bleaching by elemental chlorine free (ECF) or totally
chlorine free (TCF) processes. The wastewater is purified by secondary treatment (mechanical, chemical and biological) which
removes most of the toxic substances from the discharge. However, we found residual toxicity in the high molecular (> 1000
D) matter (HMWM) of the discharge by test of the RET (reverse electronic transfer) inhibition.
This fraction consists mainly of polydisperse lignin (LIG) and carbohydrate (CH) macromolecules. Structural units in these
molecules are studied by pyrolysis gas chromatography / mass spectrometry (Pyr-GC/MS). In the present work, our aim was to
find out those structural units which could explain the RET toxicity of LIG or CH molecules. We compared statistically RET
toxicity values of the HMWM samples from treated wastewaters of pilot pulping experiments and intensity variation of the pyrolysis
product gas chromatograms of these samples. This application is a novel study procedure.
Methods Pyrolysis products (Py-GC/MS results) and inhibition of RET (reverse electronic transport toxicity) as TU50 and TU20 of HMWM
(High Molecular Weight Material; Mw > 1000 D) were compared by multivariate statistics. The samples were from laboratory pilot
stages of TCF (Totally Chlorine Free) and ECF (Elemental Chlorine Free) manufacture of softwood pulp. Py-GC/MS was done without
and with addition of TMAH (Tetra Methyl Ammonium Hydroxide). The name and structure of each abundant fragment compound was
identified from its retention time and mass spectrum compared to authentic reference compounds or literature. Four sets of
Toxicity Units (TUs) and GC peak areas of the pyrolysis fragments were obtained. The data were normalized by division with
LIG (lignin content of each sample). TU values were dependent and the fragment values independent (explanatory) variables
in statistical treatments by SPSS system. Separate analyses of correlations, principal components (PCA) and stepwise multiple
linear regression (SMLR) were performed from the four sample sets TCF and ECF with and without TMAH.
Results and Discussion From the CH fragments, 2-furfural in TCF, and from the LIG fragments, styrene in ECF showed the highest probabilities to
originate from source structures of toxicity. Other possible compounds in concern were indicated to be CH fragment 2-methyl-2-cyclopenten-1-one
in ECF and LIG fragments 2-methoxy-4-methylphenol, 4,5-dimethoxy-2-methylphenol and 2-methylphenol in TCF. 相似文献
576.
固相微萃取-毛细管气相色谱法快速分析水中酞酸酯 总被引:10,自引:0,他引:10
用固相微萃取富集水中酞酸酯,毛细管气相色谱分离分析,整个分析过程只需50min,检出限可达0.01-40.0μg/L,实验表明,固相微萃取是一种快速、简便、集萃取浓缩进样于一体的样品前处理技术,具有分析时间短、灵敏度高、无需有机溶剂的优点,已用于地面水源、海水、饮用水中酞酸酯含量的测定。 相似文献
577.
城市污水处理厂水样中菊酯类农药残留分析 总被引:9,自引:0,他引:9
建立了基于C18固相萃取柱和气相色谱/电子捕获(GC/ECD)分析水体中环境激素类物质——菊酯类农药的分析方法,并对方法的回收率、灵敏度进行了评价,同时分析了北京市高碑店、北小河两个城市污水处理厂进水与出水中菊酯类农药的浓度,研究发现在其废水中存在联苯菊酯、氯氰菊酯、氰戊菊酯和溴氰菊酯,浓度在0.013~0.920μg/L之间。结果表明,曝气活性污泥法对菊酯类农药的去除效果较好。方法对菊酯类农药的回收率达到67.7%~96.2%,方法检测限为0.010~0.015μg/L。 相似文献
578.
Recommendations for Monitoring of Polybrominated Diphenyl Ethers in the Canadian Environment 总被引:1,自引:0,他引:1
Alaee M 《Environmental monitoring and assessment》2003,88(1-3):327-341
Polybrominated diphenyl ethers (PBDEs) have been reported in air, surface waters, suspended sediments, soil, sediment, fish, marine mammals, and bird eggs throughout Canada, from the St. Lawrence Estuary to the Strait of Georgia and the northernmost reaches of the Canadian Arctic. Canadian scientists have detected the presence of PBDEs in breast milk in every Canadian province. In fact, recent data on temporal trends strongly suggests that the concentrations of PBDEs are on the rise in the Canadian environment. These findings are similar to those reported in other nordic countries, and have prompted several countries to implement environmental monitoring programs. Among the key challenges currently facing Canada and other countries concerns how best to measure these chemicals in different matrices. In this paper, several analytical methods cited in the scientific literature for determining PBDE concentrations in different abiotic and biological matrices are reviewed. The critical criteria required for accurate determination of PBDEs in complex environmental matrices are discussed, including instrument sensitivity, reliability, potential interference's and the need for specialized instrumentation for the determination of compounds up to 975 Daltons. While a single analytical method that meets these and other criteria has not yet been perfected by scientists, GC/HRMS-based methods amenable to isotope dilution techniques warrant further refinement, and likely represent the best tools for future environmental monitoring programs. 相似文献
579.
采用GC/MS联用仪对焦化、染料废水和地表水中有机物进行定性、定量分析,探讨了污染源与受纳区的地表水中有机物种类和含量间的关系。 相似文献
580.
试验了水和废水中溴丙磷的气相色谱分析法。采用二氯甲烷萃取,HP-110m×530μm×2 65μm大口径毛细管柱分离,火焰光度检测器(FPD)检测,得到了良好的分离效果。检出限可达0 0007mg/L(萃取10倍),相对标准差为2 6%。 相似文献