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851.
Krein A Audinot JN Migeon HN Hoffmann L 《Environmental science and pollution research international》2007,14(1):3-4
Background, Aim and Scope
Current scientific studies and evaluations clearly show that an increase of urban dust loads, alone or combined with other
pollutants und certain meteorological conditions lead to different significant health effects. Premature death, increased
hospital admissions and increased respiratory symptoms and diseases as well as decreased lung function can be observed in
combination with high pollutant levels. Sensitive groups like elderly people or children and persons with cardiopulmonary
diseases such as asthma are more strongly affected. Because of the direct contact between fine particles and lung tissue more
information concerning the surface structure (mapping of toxic elements) is required.
Materials and Methods:
The NanoSims50 ion microprobe images the element composition at the surface of sub-micrometer air dust particles and documents
hot spots of toxic elements as a possible threat for human health.
Results:
The atmospheric fine dust consists of a complex mixture of organic and inorganic compounds. Heavy metals are fixed on airborn
particles in the form of hot spots in a nanometer scale. From a sanitary point of view, the hot spots consisting of toxic
elements are particularly relevant as they react directly with the lung tissues.
Discussion:
To what extent particles can penetrate the various areas of the lungs and be deposited there depends on the one hand on their
physical characteristics and on the other on breathing patterns and the anatomy of the lung, which is subject to change as
the result of growth, ageing or illness. Once inhaled, some particles can reach the pulmonary alveoli and thus directly expose
the lung tissues to toxic elements.
Conclusions:
Especially the mapping of toxic arsenic or heavy metals like copper on the dust particles shows local hot spots of pollution
in the dimension of only 50 nanometers.
Recommendations and Perspectives:
Imaging of elements in atmospheric particles with NanoSIMS will help to identify the material sources. 相似文献
852.
D'Emilio M Chianese D Coppola R Macchiato M Ragosta M 《Environmental monitoring and assessment》2007,125(1-3):137-146
In the framework of the development of new methods for measuring and monitoring soil pollution, this paper deals with the
use of magnetic methodologies to monitor the heavy metals presence in soils. In particular it shows a procedure for collecting
magnetic susceptibility measurements in order to interpret them as proxy variable for monitoring heavy metals in soils. Magnetic
measurements are carried out using a magnetic susceptibility meter with two different probes for in situ field surveys. The
experimental procedure is divided in two parts. In the first part we carry out laboratory tests aimed to evaluate, for both
the probes, the effective investigation depth for soil, the measurement reproducibility under different conditions, and the
influence of water content. We complete this part comparing in situ measurements obtained by means of two probes with different
characteristics. In the second part we carry out tests to evaluate the relationships between heavy metal levels and magnetic
susceptibility values of soil samples. We investigate the variability of the magnetic susceptibility measurements contaminating
different soil samples with well known concentration of heavy metals. Moreover we study the correlation between magnetic susceptibility
values and metal concentrations, determined by means of AAS, in soil samples collected during a field survey. Results suggest
that a careful check of the experimental procedure play a crucial role for using magnetic susceptibility measurements for
heavy metals in situ monitoring. This is very helpful both for improving the quality of data and for making simpler data interpretation. 相似文献
853.
Objective This study was done to estimate whether heavy metals in the air may affect endometrial chemical composition.
Materials and Methods A total of 30 albino Wistar rats were employed and randomly divided into three groups. The rats of Group 1 and 2 were acutely
and sub-chronically exposed to the gas form of heavy metals, respectively. Group 3 was used as a control group. Endometrial
tissue worth of heavy metals of the groups was measured in through using scanning electron microscope.
Results A statistically no significant difference was found for endometrial chemical composition of all of the heavy metals (chrome,
manganese, iron, cobalt, nickel, zinc and lead) between group 1 and 2 (p > 0.05). On the other hand, there was statistically significant difference for all of the heavy metals between group 1 and
group 3 (p < 0.05), while there was statistically significant difference for chrome, manganese, iron, cobalt and nickel (p < 0.05), but zinc and lead (p > 0.05) between group 2 and 3.
Conclusion Air pollutants of Pb and Zn resulting mostly from combustion of fossil fuels and certain special industrial process in Kirikkale
may be a risk factor for the high pregnancy loses by changing endometrial homeostasis. 相似文献
854.
Surface sediment samples (n = 18) were collected from the Algerian Mediterranean coasts and analyzed for seven metals using inductively coupled plasma-optical
emission spectrometry in order to asses the distribution and bioavailability of metals and to study the anthropogenic factors
affecting their concentrations. Sediment samples were size-fractionated into three sizes: 1,080–500 (coarse), 500–250 (medium),
and <250 mm (fine). Bulk sediments were subjected to both sequential extraction and total digestion to evaluate the reliability
of the sequential extraction procedure (SEP), while the fractions have been only sequentially extracted for metals speciation.
The metals were sequentially extracted into five phases namely exchangeable (P1), carbonates (P2), Fe–Mn oxides (P3), organic
(P4) and residual (P5). Metal recoveries in sequential extractions were ±20% of the independently measured total metal concentrations;
the high recovery rates indicate the good reliability of the SEP used in this study. Correlation coefficients indicated that
the grain size has an effect on the distribution of metals in the investigated samples. The order of metal levels in the fractions
was medium > fine > coarse for all the metals. The average total extractable metal concentrations for Cd, Cr, Cu, Fe, Ni,
Pb, and Zn were 1.1, 8.8, 4.7, 1,291.3, 13.9, 5.7 and 20.4 μg/g, respectively. The northeastern shelf had the lowest metal
levels while the highest were in northwestern part mainly due to the significant tourism activities in the northwestern part.
Comparison of our results to Earth’s crust values and to previous studies points out that our samples were relatively unpolluted
with respect to the heavy metals investigated; most of the metals are not from anthropogenic sources. Enrichment factors as
the criteria for examining the impact of the anthropogenic sources of heavy metals were calculated, and it was observed that
the investigated samples were not contaminated with Cr, Cu, and Fe, moderately contaminated with Ni, Pb, and Cd, and contaminated
with Cd in some sites. The P5 phase had the highest percents of Cr, Cu, Fe, Ni, and Zn. Cadmium and lead were predominant
in the P4 phase, while Cu, Fe and Zn were distributed in the order P5 > P3 > P4 > P2 > P1. The following order of bioavailability
was found with the heavy metals Pb > Cr > Cd > Ni > Zn > Cu > Fe. 相似文献
855.
Soylak M Divrikli U Saracoglu S Elci L 《Environmental monitoring and assessment》2007,127(1-3):169-176
Cellulose nitrate membrane filter was used for the preconcentration-separation of Cu, Co, Cd, Pb and Cr ions. The analyte
ions were collected on the membrane filter by the aid of carmine. Then membrane filter was dissolved by using nitric acid.
The levels of the analytes in the final solutions were determined by flame atomic absorption spectrometry (FAAS). The analytical
parameters including pH, amounts of carmine, sample volumes etc. have been optimized. No influences have been observed from
the matrix ions. The detection limits for analytes were in the range of 0.08 μg/l-0.93 μg/l. The validation of the procedure
was checked by the analysis of standard reference sediment (GBW 07309). The present method has been successfully applied for
the FAAS determinations of analyte ions in real samples including black tea and magnesium salts. 相似文献
856.
Quality parameters from 17 sampling stations from Lake Koronia and 18 from Lake Volvi were determined during sampling period
of one year. Physicochemical parameters (pH, conductivity, DO) did not show remarkable differences neither between sampling
sites nor between sampling periods. Nutrient concentrations (nitrogen and phosphorus compounds) were higher in lake Koronia
than in Volvi showing relatively small temporal and spatial variations. As far as heavy metals in sediments, lake Koronia
is considerably more polluted than Volvi lake especially with the metals Fe, Mn, Zn, Pb and Cd. The mean total concentrations
of metals in lake Koronia decrease in the order Mn > Zn > Cr > Pb > Cu > Fe > Cd. The mean total concentrations of metals
in lake Volvi decrease in the order Mn > Zn > Cr > Cu > Pb > Fe $>$ Cd. 相似文献
857.
Coal-Mine Hollow Fill and Settling Pond Influences on Headwater Streams in Southern West Virginia, USA 总被引:1,自引:0,他引:1
Merricks TC Cherry DS Zipper CE Currie RJ Valenti TW 《Environmental monitoring and assessment》2007,129(1-3):359-378
The influences of coal-mine hollow fills and associated settling ponds in three headwater streams were assessed in southern
West Virginia, USA. Fill drainage waters had elevated conductivities and metal concentrations, compared to a regional reference.
Benthic macroinvertebrate richness was not affected consistently by the hollow fill drainages, relative to a regional reference,
although a more tolerant community, lacking in Ephemeroptera taxa at most locations, was evident. Collector-filterer populations were elevated at monitoring stations directly below the
settling ponds, indicating that the ponds’ presence influenced macroinvertebrate community structure by means of organic enrichment.
Corbicula fluminea growth was enhanced in monitoring locations directly below the settling ponds, also an apparent result of organic enrichment.
Results of acute water column toxicity testing with Ceriodaphnia dubia, sediment chronic toxicity testing with Daphnia magna, and in-situ ecotoxicological assessments with C. fluminea demonstrated no mortality or toxic influence at most of the sites tested below the ponds. The settling ponds appear to serve
as sinks in collecting some, but not all, trace metals. 相似文献
858.
Park GS 《Environmental monitoring and assessment》2007,135(1-3):153-162
Spatial and temporal distribution patterns of total suspended solids (TSS) in the shallow and macrotidal regions of the Korean
peninsula indicated there were significant changes in TSS concentrations. These were seasonally influenced by the wind, river
input and tidal cycle. There were high TSS values at estuarine and river mouth stations and during low tide due to the re-suspension
of bottom sediment by strong wind action during winter months, in addition the land input through rivers and strong tidal
current during ebbing. Monthly mean values of TSS significantly correlated with wind speed and nitrate concentration (p < 0.01). This indicated that the resuspension of surface sediment was a more important source of TSS than the river input,
and that nitrate was introduced into the water column during the resuspension process. TSS were seven times higher at low
tide than in high tide. Light penetration was significantly inhibited by TSS; as >98% of incident light was absorbed within
2 m and zero photosynthetically active radiation (PAR) under 2 m in the estuarine stations during winter. Removal of heavy
metals and nutrients by TSS in the water column was evident. Over 80% of the initial concentration of nutrients was removed
within 10 min under various concentrations of TSS and also TSS contained significantly higher concentration of heavy metals
than surface sediment. The concentration levels of nutrients and chemical oxygen demand in the west coast were comparable
with the East and South Sea, even the major rivers in the Korean peninsula flow into the West Sea with major pollutant loadings
into the coastal areas. High concentration of TSS is likely to contribute to the removal process of these pollutants, resulting
in relatively lower levels of nutrients and organic materials in these coastal waters. 相似文献
859.
生物可降解螯合剂[S,S]-乙二胺二琥珀酸和乳酸乙酯提取土壤中重金属的研究 总被引:1,自引:0,他引:1
研究了生物可降解的有机螯合剂[S,S]-乙二胺二琥珀酸([S,S]-EDDS,简写为EDDS)和乳酸乙酯(EL)对重金属污染土壤中重金属的提取效率,并用X射线衍射(XRD)和红外光谱(FT-IR)分析了螯合剂提取对土壤理化性质的影响.结果表明:EDDS对土壤中的Cd、Cu、Pb和Zn有较高的提取率,效果比EL好;EDDS和EL混合提取的重金属提取率增加,但相比单独使用EDDS没有超过10%.FT-IR分析表明,提取前后FT-IR谱图中特征吸收频率没有显著改变,但强度有所改变.XRD分析表明,提取前后土壤晶格结构发生明显的变化,螯合剂提取改变了土壤微观结构. 相似文献
860.
蚯蚓活动对重金属在土柱中淋溶行为的影响 总被引:2,自引:0,他引:2
采用土柱淋溶方法,以溴离子为示踪离子,研究了蚯蚓活动形成的土壤大孔隙对铜和锌离子在土柱中迁移行为的影响.运用平衡和非平衡对流-弥散模型对溴离子和铜、锌离子在不同土柱中的穿透曲线进行拟合.结果表明,蚯蚓活动形成的蚯蚓孔能够产生明显的优势流现象,这种优势流极大地加快了重金属离子在土柱中垂直向下迁移的速度.非平衡对流-弥散模型能很好地预测溴离子和铜、锌离子在蚯蚓孔土柱中的流出趋势,而平衡对流-弥散模型适合于预测溶质在对照(匀质)土柱中的流出趋势. 相似文献