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991.
Passive sampling devices (PSDs) sequester the freely dissolved fraction of lipophilic contaminants, mimicking passive chemical uptake and accumulation by biomembranes and lipid tissues. Public Health Assessments that inform the public about health risks from exposure to contaminants through consumption of resident fish are generally based on tissue data, which can be difficult to obtain and requires destructive sampling. The purpose of this study is to apply PSD data in a Public Health Assessment to demonstrate that PSDs can be used as a biological surrogate to evaluate potential human health risks and elucidate spatio-temporal variations in risk. PSDs were used to measure polycyclic aromatic hydrocarbons (PAHs) in the Willamette River; upriver, downriver and within the Portland Harbor Superfund megasite for 3 years during wet and dry seasons. Based on an existing Public Health Assessment for this area, concentrations of PAHs in PSDs were substituted for fish tissue concentrations. PSD measured PAH concentrations captured the magnitude, range and variability of PAH concentrations reported for fish/shellfish from Portland Harbor. Using PSD results in place of fish data revealed an unacceptable risk level for cancer in all seasons but no unacceptable risk for non-cancer endpoints. Estimated cancer risk varied by several orders of magnitude based on season and location. Sites near coal tar contamination demonstrated the highest risk, particularly during the dry season and remediation activities. Incorporating PSD data into Public Health Assessments provides specific spatial and temporal contaminant exposure information that can assist public health professionals in evaluating human health risks. 相似文献
992.
Two sediment matrices with different characteristics were amended with chars from different sources for bioaccumulation assay with filter-feeding Chironomus plumosus larvae. Chars greatly decreased porewater concentrations of PAHs (Ciw) measured using polyethylene devices in sediments. In organic rich sediment matrix-based systems where suspended char particles were absent, PAH concentrations in larvae (CiB) were significantly correlated with Ciw, and there was no difference in water-based bioaccumulation factors (BAFs) between different treatments, suggesting that water absorption was the main contaminant uptake route for larvae. In organic poor sediment matrix-based systems where suspended char particles were present, poor Pearson correlation between CiB and Ciw was found, but there was a significant linear increase of BAF values with char contents, which indicated that ingestion of suspended char particles could also be important for PAH bioaccumulation. Therefore, we need to rethink of the effectiveness and risks for the application of black carbon to sediment/soil remediation. 相似文献
993.
Laumann S Micić V Kruge MA Achten C Sachsenhofer RF Schwarzbauer J Hofmann T 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2690-2697
The release of unburnt coal particles and associated polycyclic aromatic hydrocarbons (PAHs) may cause adverse impacts on the environment. This study assessed variations in the concentration and composition of PAHs in a set of fifty coal samples from eleven coal basins worldwide. The maximum PAH concentrations at high volatile bituminous rank were recorded in samples from a single basin. Considering the entire sample set, the highest PAH concentrations were in fact found outside of this rank range, suggesting that the maceral composition and thus the coal’s origin also influenced PAH concentrations. The examination of the PAH compositions revealed that alkylated 2-3 ring PAHs remain dominant compounds irrespective of coal rank or origin. Multivariate analysis based on PAH and maceral content, bulk and maturity parameters allowed the recognition of seven groups with different rank and origin within the coal sample set. 相似文献
994.
Determination of polycyclic aromatic hydrocarbons in urban street dust: implications for human health 总被引:4,自引:0,他引:4
The determination of sixteen polycyclic aromatic hydrocarbons in urban street dust has been done. Samples were collected from 12 sampling locations in a city centre location (Newcastle upon Tyne, north east England) and extracted using in situ pressurised fluid extraction followed by gas chromatography mass spectrometry. From the results it was possible to identify three groups, with respect to PAH concentration, with PAH contents ranging between 0.6-2.3 mg kg−1, 15.6-22.5 mg kg−1 and 36.1-46.0 mg kg−1. The total PAH content of samples from these sampling sites has been compared to 22 urban locations around the world; comparable levels were found in these samples compared to the other cities around the world.The potential source of PAHs has been investigated by investigating the proportion of pyrogenic and petrogenic material in urban street dust using specific individual PAH ratios. The results indicate that the PAH content of urban street dust from the chosen sites are more likely to be due to pyrogenic sources i.e. vehicle exhaust emissions. The particle size fractions (<63 μm; 63-125 μm; 125-250 μm; 250-500 μm; 500-1000 μm; and 1000-2000 μm) of individual PAHs in three selected sampling sites was investigated. In two of the selected sites the PAH content was independent of particle size whereas in sampling site 10 elevated PAH levels are noted in the <63 μm size fraction. Sampling site 10 is located at the junction of three road tributaries which are used as major access points to the east of the city centre. Finally, the potential health risk for unintentional consumption of PAHs was assessed in terms of a mean daily intake (based on an ingestion rate of 100 mg d−1). It was found that all 4-6 membered ring PAHs had concentrations in excess of the mean daily intake thereby reflecting a potential health risk, particularly in the smallest size particle fractions. 相似文献
995.
996.
Dynamic changes in microbial activity and community structure during biodegradation of petroleum compounds: A laboratory experiment 总被引:5,自引:0,他引:5
With 110-d incubation experiment in laboratory,the responses of microbial quantity,soil enzymatic activity,and bacterial community structure to different amounts of diesel fuel amendments were studied to reveal whether certain biological and biochemical characteristics could serve as reliable indicators of petroleum hydrocarbon contamination in meadow-brown soil,and use these indicators to evaluate the actual ecological impacts of 50-year petroleum-refining wastewater irrigation on soil function in Sbenfu irrigation area.Results showed that amendments of≤1000 mg/kg diesel fuel stimulated the growth of aerobic beterotrophic bacteria,and increased the activity of soil dehydrogenase,hydrogenperoxidase,polypbenol oxidase and substrate-induced respiration.Soil bacterial diversity decreased slightly during the first 15 d of incubation and recovered to the control level on day 30.The significant decrease of the colony forming units of soil actinomyces and filamentous fungi can be taken as the sensitive biological indicators of petroleum contamination when soil was amended with≥5000 mg/kg diesel fuel.The sharp decrease in urease activity was recommended as the most sensitive biochemical indicator of heavy diesel fuel contamination.The shifts in community structure to a community documented by Sphingomonadaceae withinα-subgroup of Proteobacteria could be served as a sensitive and precise indicator of diesel fuel contamination.Based on the results described in this paper,the soil function in Shenfu irrigation area was disturbed to some extent. 相似文献
997.
Seven polycyclic aromatic hydrocarbons (PAHs) in atmospheric particulates were determinated by high performance liquid chromatography (HPLC) with fluorescence detector using direction injection and an on-line enrichment trap column.The method simplified the sample pretreatment,saved time and increased the efficiency.With the on-line trap column,PAHs were separated availably even underground injecting 1.0 ml sample with relatively high column efficiency.The recoveries of the seven PAHs were from 85% to 120% for spiked atmospheric particulate sample.The limit of detection was 15.3-39.6 ng/L (S/N=3.3).There were good linear correlations between the peak areas and concentrations of the seven kinds of PAHs in the range of 1-50 ng/ml with the correlation coefficients over 0.9970.Furthermore,it also indicated that the method is available to determine PAHs in atmospheric particulates well. 相似文献
998.
G. Andreou S. D. Alexiou G. Loupa S. Rapsomanikis 《Water, Air, & Soil Pollution: Focus》2008,8(1):99-106
The organic chemical composition of the fine fraction of atmospheric particulate matter in Athens has been studied, in order
to establish emission sources. The results of the analyses of the aliphatic fraction indicate that all samples contain n-alkanes ranging from C14 to C32, with C25, C26, C27 and C29 being the more abundant congeners. Fossil fuels biomarkers such as extended tricyclic terpanes (hopanes, steranes) and isoprenoid
hydrocarbons (pristane, phytane) were observed in our samples on a daily basis. Source reconciliation was conducted using
molecular diagnostic ratios (such as the carbon preference index – CPI). The mean CPI value (1.84) indicates the mixed origin
of the Athenian fine particles. The notable presence of an unresolved complex mixture or “hump” of hydrocarbons in our gas
chromatograms is indicative of petrogenic hydrocarbon inputs. An approximate measure of this kind of contamination is the
ratio of the concentrations of unresolved components to the resolved n-alkanes and other major compounds (U:R). The high U:R value of 25.25 further confirmed the major contribution of fossil fuels.
Yet, the percent contribution of leaf wax n-alkanes (25.15%) indicated the parallel contribution of biogenic sources. This work supports the conclusion that vehicular
emissions were the major source of aliphatic organic compounds with a smaller contribution of biogenic n-alkanes during the study period in Athens. 相似文献
999.
1000.
Ataria JM O'Halloran K Gooneratne R 《Environmental science and pollution research international》2007,14(4):256-265
Background Monitoring biological responses that are mediated via the aryl-hydrocarbon receptor (AhR) in animals exposed to environmental
contaminants can indicate both the presence to chemicals that act through this biochemical pathway and whether these chemicals
are bioavailable.
Objectives The use of an ex-situ method that incorporated biological responsiveness monitoring in mice for determining the presence of
‘biologically active’ hydrocarbons in contaminated soils was investigated.
Methods The use of C57BL/6 as a test organism was validated by determining hepatic and immune responsiveness to two polyaromatic hydrocarbons
(PAHs): 3,4 benz[a]pyrene (B[a]P) and 1,2 benz (a)anthracene (BA) administered via intraperitoneal (i.p.) injection. The responsiveness
of mice exposed to soils spiked with hydrocarbons or ex situ exposures to soil removed from two contaminated sites was also
investigated.
Results and Discussion Mice that were exposed to B[a]P via i.p. injections showed a 14-fold increase in liver microsomal ethoxyresorufin O-deethylase
(EROD) activity compared to the control group. In contrast EROD activity following BA exposure at the same level was not significantly
enhanced. Mouse immune response was significantly inhibited in a dose-dependent manner by i.p. injections of B[a]P. No significant
inhibition occurred with the same doses of BA. Following i.p. exposure, the retention of B[a]P in mouse carcasses was greater
than BA. Mice exposed to clean soils spiked with environmentally relevant concentrations of B[a]P and BA failed to show any
significantly different hepatic or immune responses. Carcass residue data indicated a limited uptake of PAH from the soil.
In contrast, EROD activity in mice exposed (ex situ) to hydrocarbon-contaminated soils removed from a fuel-loading depot and
decommissioned gas works was significantly enhanced (4- and 2-fold respectively). However, this increase in EROD activity
did not appear to correlate with either soil or carcass PAH concentrations.
Conclusions and Outlook These results support the assumption that B[a]P has a higher affinity for the aryl hydrocarbon receptor (AhR) compared to
BA. Soil parameters such as organic carbon content, structure and particle size distribution can modulate the bioavailability
of contaminants to biological receptors. These factors are implicated in the lack of responsiveness demonstrated in the spiked
soil experiments. However the responsiveness of EROD activity in mice exposed (ex situ) to soil contaminated with complex
mixtures of hydrocarbon compounds confirms the potential usefulness of this model to determine the presence of ‘biologically
active’ compounds in aged soils removed from contaminated sites. 相似文献