首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   139篇
  免费   0篇
  国内免费   6篇
废物处理   1篇
环保管理   8篇
综合类   10篇
基础理论   28篇
污染及防治   77篇
评价与监测   17篇
社会与环境   4篇
  2023年   2篇
  2022年   6篇
  2021年   2篇
  2020年   1篇
  2019年   1篇
  2018年   5篇
  2017年   3篇
  2016年   2篇
  2014年   4篇
  2013年   13篇
  2012年   6篇
  2011年   16篇
  2010年   6篇
  2009年   1篇
  2008年   17篇
  2007年   12篇
  2006年   8篇
  2005年   6篇
  2004年   5篇
  2003年   3篇
  2002年   7篇
  2001年   4篇
  2000年   2篇
  1999年   2篇
  1998年   1篇
  1995年   1篇
  1993年   2篇
  1991年   1篇
  1989年   4篇
  1987年   1篇
  1969年   1篇
排序方式: 共有145条查询结果,搜索用时 31 毫秒
61.
Soil and sediments collected at a former chlor‐alkali plant in coastal Georgia (United States), revealed the presence of PCDF concentrations as great as 82.3 ng/g, dry wt. PCDF congener profile in soil was typical of “chlorine pattern”; with elevated proportions of OCDF and HpCDF. Concentrations of PCDFs declined gradually by 44‐fold at a distance of about 500 m along the contamination gradient. Of PCDDs/DFs, 2,3,7,8‐substituted PCDFs accounted for 94–98% of the TCDD‐like activity, which declined by 25‐fold, corresponding with the reduction of total PCDF concentrations. Concentrations of PCDDs in sediments were as great as 17 ng/g, with an elevated contribution from OCDD. The magnitude of decline in PCDD concentrations with distance from the source was less pronounced than that for PCDFs. PBDDs and PBDFs were not detected. Polybrominated biphenyl ether (PBBE) and monobromo‐heptachloro dibenzo‐p‐dioxins and dibenzofurans (PXDDs/DFs) were found, though, at low concentrations. Their spatial distribution was similar to those of PCDDs.  相似文献   
62.
Perfluorinated compounds have been manufactured in large quantities and used in myriad industrial processes and commercial applications. The aim of this preliminary study was to generate hypotheses with regard to differences in body burdens of perfluoroalkyl acids, among a sub-sample of participants from the New York State Angler Cohort Study, over a time interval during which no known substantial changes occurred in US manufacturing practices or commercial use. Paired serum specimens, collected from 15 subjects in 1993–1994 (time 1), and in 1995–1997 (time 2), with a minimum interval of 2.5 years, were assayed for PFDA, PFHpA, PFHxS, PFNA, PFOA, PFOS, PFOSA and PFUnDA using HPLC with ES-MS/MS. By subject, differences in concentrations between time 1 and time 2 were estimated, employing paired t-tests, correlations, and multivariable linear regression to accommodate heterogeneity in duration between specimens, and in time 1 concentrations. A statistically significant (P < 0.05) adjusted mean decrease of 0.16 ng mL?1 (18.8%) between time 1 and 2 was detected for PFNA, and an adjusted mean increase of 0.54 ng mL?1 (56.8%) was detected for PFOA. The results of this study may be indicative of short-term changes in human body burdens of PFNA and PFOA in association with local exposure sources.  相似文献   
63.
建立了固相萃取(SPE)/气相色谱质谱(GC/MS)联用检测灰尘中氯代多环芳烃(ClPAHs)的方法.以正己烷和二氯甲烷混合液为提取溶剂,索氏提取灰尘样品中的20种ClPAHs,活性硅胶层析柱与活性炭混合硅胶SPE柱协同净化.净化后的提取液采用GC/MS测定,SIM模式扫描,并用质谱特征离子定量分析.结果表明,填充量为0.2 g(W(活性炭)∶W(硅胶)=1∶40)的活性炭混合硅胶SPE小柱能有效地将ClPAHs分离出来,载样后采用反向溶剂洗脱,既提高了回收率又减少了洗脱剂甲苯的用量,净化效果好.处理灰尘样品后检测分析,20种ClPAHs的平均回收率稳定在60.4%—120.1%,相关系数>0.99,检出限为0.04—0.17 ng.g-1,相对标准偏差为1.6%—10.2%.本方法前处理简单,定性、定量准确可靠,可广泛应用于环境介质中氯代多环芳烃的检测.  相似文献   
64.
The isotope dilution technique was applied for the analysis of new polybrominated diphenylethers (PBDEs) calibration standard (both labeled and non-labeled) using high-resolution gas chromatography-high-resolution mass spectrometry (HRGC-HRMS). The relative response factor (RRF) and relative standard deviation (RSD) for new calibration standard in Finnigan Thermo Electron (MAT-95XL) and Micromass (Autospec Ultima) were more or less identical with mean RRF (0.9882), RSD (0.0865) and CV% of (8.75). The results also revealed for DeBDE-209 quantification; labeled DeBDE-209 is essential. Furthermore, we recommend on column injection technique with a thin film instead of splitless injection in order to reduce the thermal degradation of DeBDE-209 and formation of octabromodibenzofurans (OBDF). Besides, analysis of human blood (n = 156) of FEBRA-intake and non-FEBRA-intake individuals elucidated frequent detection of eighteen PBDE congeners. The average PBDE concentrations in non-FEBRA intake and FEBRA-intake humans were 6000-11,000 (mean: 8400) and 5400-15,000 (mean: 9900) respectively on pg/g fat basis. Although FEBRA-intake individuals showed slightly greater PBDEs, computer-normalized concentrations of TeBDE-47 corroborate FEBRA-intake individual from four family showed reduced concentrations. The contamination profiles of PBDEs varied in between family, gender as well as geography. International comparison with predominant PBDE congener (TeBDE-47) prevailed lower levels in Japan when compared to Korea, Germany and USA nevertheless, congener specific profiles were different which is in accordance with different technical PBDE usage in between countries.  相似文献   
65.
To understand nonylphenol (NP) contamination in the northeast coastal environment in China, NP was determined in 19 sediment and 20 bivalve samples collected during November 2005. NP was identified in all sediment samples in the range of 8.8 to 1.0 × 10 3 ng/g dw (dry weight), with an average of 0.12 × 10 3 ng/g dw. Most of the bivalve samples (oysters and mussels) contained detectable amounts of NP that ranged from ND (not detected) to 7.6 × 10 3 ng/g dw, with an average value of 0.79 × 10 3 ng/g dw. These results indicated that NP is ubiquitous in sediments and bivalves from the northeast coast of China, and are even present in bivalves sold as seafood. Serious contamination with NP was recorded off the coast of Bohai Strait and in semi-enclosed coastal environment such as Jiaozhou Bay and Liaodong Bay. Possible environmental and human health implications were understood in this study.  相似文献   
66.
A study was made on the physico-chemical characteristics of water samples mixed with effluent discharged from textile industries at Chellandipalayam (Site--I), Senaparatti (Site--II) and Pasupathipalayam (Sites--III and IV) revealed the elevated levels of Ca, Mg, Na, Cr, K, Ni, Cu, Zn, CO3, SO4, NO3 and Cl- . The concentrations of these ions exceeded the limit prescribed by ISI. The increase in the concentrations of ions was revealed by higher values of electrical conductivity (EC). Water at these sites was found to be hard, brackish and unsuitable for drinking purpose. In all these sites, the seed germination of rice alone was significantly affected among the other crops tested. Irrigation of crops with ground water notably lowered the quantity of reserve food in rice, wheat (starch), and sugarcane (sugar), indicating the interference of their metabolic pathway by polluted ground water.  相似文献   
67.
The present investigation deals with an application of integrated sequential oxic and anoxic bioreactor(SOABR) and fluidized immobilized cell carbon oxidation(FICCO) reactor for the treatment of domestic wastewater with minimum sludge generation. The performance of integrated SOABR-FICCO system was evaluated on treating the domestic wastewater at hydraulic retention time(HRT) of 3 hr and 6 hr for 120 days at organic loading rate(OLR)of 191 ± 31 mg/(L·hr). The influent wastewater was characterized by chemical oxygen demand(COD) 573 ± 93 mg/L; biochemical oxygen demand(BOD5) 197 ± 35 mg/L and total suspended solids(TSS) 450 ± 136 mg/L. The integrated SOABR-FICCO reactors have established a significant removal of COD by 94% ± 1%, BOD5 by 95% ± 0.6% and TSS by 95% ± 4% with treated domestic wastewater characteristics COD 33 ± 5 mg/L; BOD59 ± 0.8 mg/L and TSS 17 ± 9 mg/L under continuous mode of operation for 120 days. The mass of dry sludge generated from SOABR-FICCO system was 22.9 g/m~3. The sludge volume index of sludge formed in the SOABR reactor was 32 mL/g and in FICCO reactor it was 46 mL/g. The sludge formed in SOABR and FICCO reactor was characterized by TGA, DSC and SEM analysis. Overall, the results demonstrated that the integrated SOABR-FICCO reactors substantially removed the pollution parameters from domestic wastewater with minimum sludge production.  相似文献   
68.
Patterns of contamination by polychlorinated biphenyls (PCBs) were investigated in fourteen samples of coastal sediments from Hong Kong. Congener-specific analyses revealed nine sediment samples from Junk Bay to contain PCBs at concentrations ranging from 31 to 2200 ng g(-1) dry weight, concentrations generally increasing with distance north in the Bay. By contrast, five sediments from the Tolo area to the north-east of Hong Kong exhibited total PCB levels of only 6.6 to 45 ng g(-) dry weight. The patterns of relative abundance of PCB congeners in the northern Junk Bay sediments suggested the existence of ongoing source(s) of PCBs in this area; biphenyls of lower chlorination were present at high concentration in these samples. Three coplanar PCBs (3', 4, 4'-tetrachlorobiphenyl; 3,3',4,4',5-pentachlorobiphenyl; and 3,3',4,4',5,5'-hexachlorobiphenyl) were found to be present in Junk Bay sediments; these are highly toxic and are cause for concern in aquatic environments. The abundance of the three coplanar PCBs in the sediments studied was similar to that in commercial PCB mixtures, suggesting that these congeners are not enriched over other PCBs by the sediments of coastal ecosystems. It is concluded that the preferential enrichment of coplanar PCBs occurs in the biosphere, rather than in sediments.  相似文献   
69.
The bioaccumulation potential of three highly toxic coplanar PCB isomers [3,3',4,4'-tetrachlorobiphenyl (T(4)CB); 3,3',4,4',5-pentachlorobiphenyl (P(5)CB); and 3,3',4,4',5,5'-hexachlorobiphenyl (H(6)CB)] was investigated using green-lipped mussels (Perna viridis Linnaeus) as a bioindicator, through a transplantation experiment at two locations in Hong Kong waters. By contrast to the relatively rapid uptake and release of many other PCB isomers, the non-ortho chlorine substituted coplanar PCB congeners exhibited slow uptake and clearance. The kinetic parameters of coplanar PCBs based on lipid weight-related data, and the degree of bioaccumulation based on the proportion of coplanar PCBs in total PCBs in mussels, clearly indicate that coplanar PCBs are highly bioaccumulative in lower organisms. On the assumption that mussels are unlikely to be particularly unusual with respect to their bioaccumulation of coplanar PCBs, it appears most likely that these highly toxic and persistent PCB congeners are concentrated by all aquatic organisms, and may reach higher consumers (including humans) in quantities of toxicological concern.  相似文献   
70.
Isomer-specific determinations of PCB congeners in a wide variety of animal species such as fish, marine mammals (whale, dolphin and porpoise) and terrestrial mammals (dog, cat and human) revealed the environmental occurrence of highly toxic coplanar 3,3',4,4'-tetrachlorobiphenyl (T(4)CB), 3,3',4,4',5-pentachlorobiphenyl (P(5)CB) and 3,3',4,4',5,5'-hexachlorobiphenyl (H(6)CB) within a range of few pg g(-1) to several ten ng g(-1) in fat tissues (except fish) on a wet weight basis. Detection of these toxic residues in wild specimens collected from remote areas such as the North Pacific suggests the already widespread distribution of coplanar PCBs as in the case of general PCB pollution. The clear positive correlations between concentrations of total PCBs and each of the three coplanar PCBs obtained in all mammals analysed suggest that the sources of coplanar PCB contamination to the environment are mainly commercial PCB preparations. Comparison of the composition of three toxic coplanar PCBs in commercial PCB mixtures and in the various animals indicates the relative metabolisability of these congeners as follows: 3,3',4,4'-T4CB>3,3',4,4',5-P5CB>3,3',4,4',5,5'-H6CB. Moreover, marine mammals seem to have lower potency to metabolise the coplanar PCBs in comparison with terrestrial mammals. In human adipose tissues, the concentrations of coplanar PCBs were found to be much higher than 2,3,7,8-tetrachlorodibenzo-p-dioxin (T(4)CDD), 2,3,4,7,8-pentachlorodibenzofuran (P(5)CDF) and other toxic congeners. 'T(4)CDD-equivalent' analysis based on the enzyme induction potencies and the residues of these toxic chemicals indicates that 3,3',4,4',5-P(5)CB may impose a greater toxic threat than dioxins and furans to the humans and probably to wildlife also.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号