全文获取类型
收费全文 | 252篇 |
免费 | 1篇 |
国内免费 | 14篇 |
专业分类
安全科学 | 18篇 |
废物处理 | 21篇 |
环保管理 | 21篇 |
综合类 | 39篇 |
基础理论 | 49篇 |
污染及防治 | 92篇 |
评价与监测 | 18篇 |
社会与环境 | 8篇 |
灾害及防治 | 1篇 |
出版年
2022年 | 3篇 |
2021年 | 5篇 |
2020年 | 2篇 |
2019年 | 5篇 |
2018年 | 15篇 |
2017年 | 8篇 |
2016年 | 13篇 |
2015年 | 6篇 |
2014年 | 13篇 |
2013年 | 23篇 |
2012年 | 20篇 |
2011年 | 22篇 |
2010年 | 16篇 |
2009年 | 4篇 |
2008年 | 15篇 |
2007年 | 15篇 |
2006年 | 11篇 |
2005年 | 13篇 |
2004年 | 9篇 |
2003年 | 13篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1998年 | 1篇 |
1997年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1967年 | 1篇 |
1965年 | 1篇 |
1959年 | 1篇 |
1958年 | 1篇 |
1957年 | 1篇 |
1921年 | 1篇 |
排序方式: 共有267条查询结果,搜索用时 484 毫秒
261.
Comparisons of polybrominated diphenyl ethers levels in paired South Korean cord blood, maternal blood, and breast milk samples 总被引:1,自引:0,他引:1
Kim TH Bang du Y Lim HJ Won AJ Ahn MY Patra N Chung KK Kwack SJ Park KL Han SY Choi WS Han JY Lee BM Oh JE Yoon JH Lee J Kim HS 《Chemosphere》2012,87(1):97-104
Polybrominated diphenyl ethers (PBDEs), commonly used flame retardants, have been reported as potential endocrine disruptor and neurodevelopmental toxicants, thus giving rise to the public health concern. The goal of this study was to investigate the relationship between umbilical cord blood, maternal blood, and breast milk concentrations of PBDEs in South Korean. We assessed PBDE levels in paired samples of umbilical cord blood, maternal blood, and breast milk. The levels of seven PBDE congeners were measured in 21 paired samples collected from the Cheil Woman’s Hospital (Seoul, Korea) in 2008. We also measured thyroid hormones levels in maternal and cord blood to assess the association between PBDEs exposure and thyroid hormone levels. However, there was no correlation between serum thyroxin (T4) and total PBDEs concentrations. The total PBDEs concentrations in the umbilical cord blood, maternal blood, and breast milk were 10.7 ± 5.1 ng g−1 lipid, 7.7 ± 4.2 ng g−1 lipid, and 3.0 ± 1.8 ng g−1 lipid, respectively. The ranges of total PBDE concentrations observed were 2.28-30.94 ng g−1 lipid in umbilical cord blood, 1.8-17.66 ng g−1 lipid in maternal blood, and 1.08-8.66 ng g−1 lipid in breast milk. BDE-47 (45-73% of total PBDEs) was observed to be present dominantly in all samples, followed by BDE-153. A strong correlation was found for major BDE-congeners between breast milk and cord blood or maternal blood and cord blood samples. The measurement of PBDEs concentrations in maternal blood or breast milk may help to determine the concentration of PBDEs in infant. 相似文献
262.
Co-contamination of arsenic and fluoride in the groundwater of unconsolidated aquifers under reducing environments 总被引:1,自引:0,他引:1
The co-contamination of arsenic (As) and fluoride (F−) in shallow aquifers is frequently observed worldwide, and the correlations between those contaminants are different according to the redox conditions. This study geochemically explores the reasons for the co-contamination and for the redox-dependent correlations by investigating the groundwater of an alluvial aquifer in Korea. Geochemical signatures of the groundwater in the study area show that the As concentrations are enriched by the reductive dissolution of Fe-(hydr)oxides, and the correlations between As and F− concentrations are poor comparatively to those observed in the oxidizing aquifers. However, F− concentrations are strongly dependent on pH. Desorption/adsorption experiments using raw soils and citrate-bicarbonate-dithionite treated soils indicated that Fe-(hydr)oxides are the important As and F− hosts causing the co-contamination phenomenon. The weaker correlation between F− and As in reducing aquifers is likely to be associated with sulfate reduction, which removes As from groundwater without changing the F− concentration. 相似文献
263.
264.
The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and polybrominated diphenylethers (PBDEs) in 33 breast milk samples collected in 2006-2007 from primipara mothers close to four industrial areas of Slovak Republic were determined. The total PCDDs/PCDFs and dl-PCBs expressed as TEQ based on WHO TEFs 1998 in breast milk samples varied from 5.0 to 51.8 pg g−1 fat (median: 13.1 pg g−1 fat; mean: 18.0 pg g−1 fat). The measurements of seven PBDE congeners (IUPAC No. 28, 47, 99, 100, 153, 154, and 183) were performed for the first time in human milk from Slovakia. PBDE levels ranged between 0.22 and 1.62 ng g−1 fat, with median and mean value of 0.43 ng g−1 fat and 0.57 ng g−1 fat respectively. No statistically significant differences were observed between studied areas in total PBDE concentrations.Furthermore, this study presents first results concerning the daily intake (DI) of PCDDs/PCDFs and dioxin-like compounds for the most vulnerable breast-fed infant population in Slovakia. The total PCDD/PCDF and dl-PCB DI for an infant during the first 2 months of life was estimated in a range from 14.4 to 230 pg TEQ kg−1 b.w., with a median value of 58.9 pg TEQ kg−1 b.w.. The DI values substantially exceeded the tolerable daily intake (TDI) 1-4 pg TEQ kg−1 b.w. recommended by WHO. The dietary infant intake concerning PBDEs was estimated to be between 0.69 and 7.1 ng kg−1 b.w. d−1, with median value of 1.7 ng kg−1 b.w. d−1. 相似文献
265.
Model-based evaluation of controlled-release systems in the remediation of dissolved plumes in groundwater 总被引:1,自引:0,他引:1
Controlled-release, semi-passive reactive barrier systems have been recently developed as a long-term treatment option for controlling the spread of contaminant plumes in groundwater. This paper describes a new computer code, and applies it to study coupled processes of solute release, reaction, and mass transport in an in situ remediation scheme using the controlled release of potassium permanganate. Confidence with the modeling approach was developed by model verifications and simulating results of a pilot-scale test-cell experiment. Sensitivity analyses indicated the possibilities of treatment inefficiencies due to inability of transverse dispersion to mix the permanganate (MnO(4)(-)) within the zone of reaction, fluctuations in source strength due to variations in flow velocity, and the small length of treatment zone due to strong soil utilization of MnO(4)(-). Although problems associated with the fluctuating source strength and strong soil utilization can be addressed by optimizing the release rate, the inefficiency of transverse dispersion to create mixing could pose a serious limitation. Through a series of model simulations, a system of injection/withdrawal wells in a doublet arrangement was developed to facilitate lateral spreading and mixing of MnO(4)(-). A well-mixed, stable MnO(4)(-) zone with predetermined size (DxL=8m x 2m) and concentration ranges (1.5-20 mg l(-1)) was created by four 1-day injection/withdrawal pumping periods over 24 d. This type of mixing zone may persist for many years with periodic well mixing and replacements of exhausted controlled-release forms. Coupled use of the generalized code with field hydrologic data will help to optimize the design and operation of controlled-release systems in practice. 相似文献
266.
Water quality modeling has been shown to be a useful tool in strategic water quality management. The present study combines the Qual2K model with the HEC-RAS model to assess the water quality of a tidal river in northern Taiwan. The contaminant loadings of biochemical oxygen demand (BOD), ammonia nitrogen (NH3-N), total phosphorus (TP), and sediment oxygen demand (SOD) are utilized in the Qual2K simulation. The HEC-RAS model is used to: (i) estimate the hydraulic constants for atmospheric re-aeration constant calculation; and (ii) calculate the water level profile variation to account for concentration changes as a result of tidal effect. The results show that HEC-RAS-assisted Qual2K simulations taking tidal effect into consideration produce water quality indices that, in general, agree with the monitoring data of the river. Comparisons of simulations with different combinations of contaminant loadings demonstrate that BOD is the most import contaminant. Streeter-Phelps simulation (in combination with HEC-RAS) is also performed for comparison, and the results show excellent agreement with the observed data. This paper is the first report of the innovative use of a combination of the HEC-RAS model and the Qual2K model (or Streeter-Phelps equation) to simulate water quality in a tidal river. The combination is shown to provide an alternative for water quality simulation of a tidal river when available dynamic-monitoring data are insufficient to assess the tidal effect of the river. 相似文献
267.
Kocí V Ocelka T Dragoun D Vit M Grabic R Sváb M 《Environmental science and pollution research international》2007,14(2):94-101
Background, Aim and Scope
The article is focused on dioxin, furan, PCB and organochlorine pesticide monitoring in the surface waters of the Central
European, protected natural reserve Krivoklatsko, under the UNESCO programme Man and Biosphere. Persistent compounds are presently
transported via different means throughout the entire world. This contamination varies significantly between sites. This raises
the question of what constitutes the naturally occurring background levels of POPs in natural, unpolluted areas, but which
are close to industrialised regions. Information of real background POP contamination can be of high value for risk assessment
management of those sites evidently polluted and for the defining of de-contamination limits.
Preserved areas should not be seen as isolated regions in which the impacts of human activities and natural factors are either
unexpected or overlooked. Every ambient region, even those protected by a law or other means, are still closely connected
to neighbouring human developed and impacted areas, and are therefore subject to this anthropogenic contamination. These areas
adjacent to natural reserves are sources of diverse substances, via entry of air, water, soil and/or biota. After an extended
period of industrial activities, organochlorine pollutants, even those emitted in trace concentrations have reached detectable
levels. For future research and for the assessment of environmental changes, present levels of contamination would be of high
importance. This work publishes data of the contamination with organochlorine pollutants of this natural region, where biodiversity
and ecological functions are of the highest order.
Materials and Methods:
Semipermeable membrane devices (SPMDs) were utilised as the sampling system. SPMDs were deployed in two small creeks and one
water reservoir selected in the central part of the Krivoklatsko Natural Reserve, where it could be expected that any possible
contamination by POPs would be lowest. The exposed SPMDs were analysed both for chemical contents of POPs and for toxicity
properties. The chemical analyses of dibenzo-dioxins, dibenzo-furans, PCBs and OCPs were analysed by GC/MS/MS on GCQ or PolarisQ
(Thermoquest). Toxicity bioassays were performed on the alga Desmodesmus subspicatus, bacteria Vibrio fischeri and crustacean
Daphnia magna. All toxicity data were expressed as the effective volume Vtox. Vtox is a toxicity parameter, the determination
of which is independent of SPMD deployment time and pre-treatment dilution (unlike, for example, the EC50 of the SPMD extract).
Results:
The following chemical parameters were monitored: 1) tetra, penta, hexa and hepta dibenzo-p-dioxins and furans; 2) all those
detectable from tri- through deca-polychloriated biphenyls (PCBs) and 3) a group of organochlorine pesticides: hexachlorobenzene
and isomers of hexachlorocyclohexane, DDE, DDD and DDT. The concentrations of dioxins and furans on the assessed sites varied
from under detection levels up to 7 pg.l-1; PCBs were detected in a sum concentration up to 2.8 ng.l-1; and organochlorine
pesticides up to 346 pg.l-1. The responses of bioassays used were very low, with the values obtained for Vtox being under
0.03 l/d.
Discussion:
Toxicity testing showed no toxicity responses, demonstrating that the system used is in coherence with the ecological status
of the assessed sites. Values of Vtox were under the critical value – showing no toxicity. The PCA of chemical analysis data
and toxicity responses resulted in no correlations between these two groups of parameters. This demonstrated that the present
level of contamination has had no direct adverse effects on the biota.
Conclusions:
The concentration values of six EPA-listed, toxic dioxins and sums of tetra-hepta dioxins; nine EPA toxic dibenzofurans and
the sums of tetra-hepta bibenzofurans are presented together with all tri-deka PCBs and organochlorine pesticides (alfa-,
beta-, gama-, delta-HCH, HCB, opDDE, ppDDE, opDDD, ppDDD, opDDT, ppDDT). These values represent possible current regional
natural background values of these substances monitored within the Central European region, with no recorded adverse effects
on the freshwater ecosystem (up until the present time).
Recommendations and Perspectives:
Assessment of dioxins, furans and other organochlorine compounds within natural reserves can be important for the monitoring
of human-induced impacts on preserved areas. No systematic monitoring of these substances in areas not directly affected by
industry has generally been realised. There is a paucity of data of the presence of any of these substances within natural
regions. Further monitoring of contamination of both soil and biota by dioxins and furans in preserve regions is needed and
can be used for future monitoring of man-made activities and/or accidents.
Semipermeable membrane devices proved to be a very good sampling system for the monitoring of trace concentrations of ambient
organochlorine compounds. Toxicity evaluation using the Vtox concept demonstrated that those localities assessed expressed
no toxicity. 相似文献