全文获取类型
收费全文 | 775篇 |
免费 | 9篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 37篇 |
废物处理 | 33篇 |
环保管理 | 82篇 |
综合类 | 98篇 |
基础理论 | 140篇 |
环境理论 | 2篇 |
污染及防治 | 234篇 |
评价与监测 | 96篇 |
社会与环境 | 61篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 5篇 |
2022年 | 18篇 |
2021年 | 17篇 |
2020年 | 10篇 |
2019年 | 17篇 |
2018年 | 30篇 |
2017年 | 31篇 |
2016年 | 41篇 |
2015年 | 24篇 |
2014年 | 32篇 |
2013年 | 102篇 |
2012年 | 35篇 |
2011年 | 54篇 |
2010年 | 39篇 |
2009年 | 25篇 |
2008年 | 38篇 |
2007年 | 37篇 |
2006年 | 40篇 |
2005年 | 24篇 |
2004年 | 21篇 |
2003年 | 20篇 |
2002年 | 15篇 |
2001年 | 8篇 |
2000年 | 10篇 |
1999年 | 6篇 |
1998年 | 3篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1992年 | 7篇 |
1991年 | 3篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1978年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1966年 | 1篇 |
1960年 | 2篇 |
1959年 | 4篇 |
1958年 | 2篇 |
1957年 | 1篇 |
1956年 | 5篇 |
排序方式: 共有785条查询结果,搜索用时 31 毫秒
691.
Crnković D Ristić M Jovanović A Antonović D 《Environmental monitoring and assessment》2007,125(1-3):75-83
Polycyclic aromatic hydrocarbons (PAHs) were analysed in 39 soil samples (0–10 cm upper layer) collected in Belgrade, the
capital of Serbia. The sampling sites were randomly selected from urban, urban/recreational and rural areas; the samples were
collected in April and December 2003 and July and October 2004.
The sum of the 16 PAHs corresponding to the recreational zone (298 μg/kg) was close to the urban zone (375 μg/kg). Mean soil
ΣPAH concentration from rural areas was 18 μg/kg dry weight. Comparing to values observed in the urbanized locations around
the world, the overall levels of PAHs in this study are low. The PAH ratios obtained pointed to a domination of pyrogenically
formed PAHs in the examined soils. The dominant PAHs in soil samples in urban zones were fluoranthene, benz[a]anthracene, phenanthrene and pyrene, mostly emitted from noncatalyst vehicles which are still in use in Serbia. The total
carcinogenic potency for each sampling site was calculated. Regardless of the used carcinogenic activity factors, carcinogenic
potency of 7 sites were 3–9 times higher than the reference ones indicating the increased carcinogenic burden of soils from
these sites. 相似文献
692.
A 3-D version of the MECCA model (Model of Estuarine and Coastal Circulation Assessment) is used to simulate the dynamics of the Eastern part of the English Channel. This area is characterized by a strong tidal turbulent regime and a frontal zone identified near the French coast by a low-salinity band. The model uses the upwind scheme to approximate the advective terms. Results show that the model overestimates the band width of the frontal zone and that this anomaly is definitely caused by the numerical diffusion introduced by the so-called upwind scheme (first-order approximation). In this paper, we study the flux-limiter schemes as an alternative to the upwind method in order to reduce this non-physical diffusion. To illustrate the improvements provided by this type of schemes, a comparison in 2-D schematic cases is made between the upwind and centered scheme with more recent higher-order schemes combined with limiter namely Minmod, Superbee, Van Leer and Monotonized Centered (MC) (called also MUSCL scheme). Respecting the CFL condition, our numerical simulations show that the flux-limiter schemes reduce the numerical diffusion and eliminate the oscillations caused by the non-limited higher-order schemes. For the schematic and realistic cases, the Superbee limiter is a good compromise between shape preservation and computational cost. 相似文献
693.
Cruz JV Pacheco D Coutinho R Cymbron R Mendes S Antunes P Fontiela J Freire P 《Journal of environmental monitoring : JEM》2010,12(12):2216-2225
Chemical monitoring of water quality on a total of 16 rivers in the Azores archipelago (Portugal), since 2003, made it possible to identify the major pressures and spatial geochemical variations along main course of the rivers. River water pollution is to a large extent associated to point sources, namely domestic wastewater discharges, especially in urban areas, and diffuse sources, associated with pasture land, and explain the high values on BOD(5) and nutrients (P and N). Heavy metals and metalloids, as well as hydrocarbons and pesticides, are generally under the detection limits of the analytical methods. Generally, river water reflects pollution loads according to a simple model, derived from land use in the watershed: in the upper part conditions are pristine, in the intermediate portion of the basin pasture land dominates and near the coast urban discharges are increasingly important. Results stress the role that an approach based on the watershed scale, coupled with land use management measures, are crucial to water management procedures and a successful WFD implementation in small river basin districts like the Azores. The paper also shows the need for full compliance regarding EU directives on urban wastewater and nitrate pollution due to agriculture. 相似文献
694.
Juliana V. Teixeira Sandra Miranda Ricardo A. R. Monteiro Filipe V. S. Lopes Joana Madureira Gabriela V. Silva Nazaré Pestana Eugénia Pinto Vítor J. P. Vilar Rui A. R. Boaventura 《Environmental monitoring and assessment》2013,185(1):59-72
The main objective of this work was to quantify and characterize the major indoor air contaminants present in different stages of a municipal WWTP, including microorganisms (bacteria and fungi), carbon dioxide, carbon monoxide, hydrogen sulfide ammonia, formaldehyde, and volatile organic compounds (VOCs). In general, the total bacteria concentration was found to vary from 60 to >52,560 colony-forming units (CFU)/m3, and the total fungi concentration ranged from 369 to 14,068 CFU/m3. Generally, Gram-positive bacteria were observed in higher number than Gram-negative bacteria. CO2 concentration ranged from 251 to 9,710 ppm, and CO concentration was either not detected or presented a level of 1 ppm. H2S concentration ranged from 0.1 to 6.0 ppm. NH3 concentration was <2 ppm in most samples. Formaldehyde was <0.01 ppm at all sampling sites. The total VOC concentration ranged from 36 to 1,724 μg/m3. Among the VOCs, toluene presented the highest concentration. Results point to indoor/outdoor ratios higher than one. In general, the highest levels of airborne contaminants were detected at the primary treatment (SEDIPAC 3D), secondary sedimentation, and sludge dehydration. At most sampling sites, the concentrations of airborne contaminants were below the occupational exposure limits (OELs) for all the campaigns. However, a few contaminants were above OELs in some sampling sites. 相似文献
695.
Distribution of heavy elements in urban and rural surface soils: the Novi Sad city and the surrounding settlements, Serbia 总被引:1,自引:0,他引:1
Biljana Škrbić Nataša Đurišić-Mladenović 《Environmental monitoring and assessment》2013,185(1):457-471
Concentrations of ten heavy elements (Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn), as well as the pH values, organic matter contents, and electrical conductivities were measured in the surface soil samples collected from 21 sites of urban areas in the city of Novi Sad, the second largest city in Serbia, its suburban settlement and the nearby villages. Range of the heavy element concentrations was from 0.16 mg/kg (for Hg) to 18,994 mg/kg (for Fe). Significantly higher Hg and Mn concentrations were observed in subgroups with rural and market garden samples in comparison to the subgroups with urban and grassland samples, respectively, while the contents of Pb found in the grasslands subgroup were significantly higher than in the subgroup with market garden soils. Only one sample of urban soil exceeded the maximum permissible value for Zn set by the relevant Serbian legislation. According to the Dutch soil quality standard, the Cd and Co concentrations in majority of the examined soils were higher than the target values for unpolluted soil. The content of Hg was above the target value in 52% of the samples, most of them belonging to the subgroup of market garden soils. The results for the Novi Sad city area were compared to the relevant data available for other cities in the Western Balkan Countries. Principal component analysis of data revealed seven outlying samples, while the rest of the analyzed samples were grouped together indicating similar heavy element patterns most probably due to mixed emission sources. 相似文献
696.
Vilicić D Terzić S Ahel M Burić Z Jasprica N Carić M Caput Mihalić K Olujić G 《Environmental monitoring and assessment》2008,142(1-3):199-218
Phytoplankton distribution and environmental characteristics were determined in a shallow, highly stratified and oligotrophic estuary (Zrmanja, eastern Adriatic). Samples were collected in two contrasting seasons; winter (February 2000), when river discharge was high, and in summer (July 2003), a period of drought. Phytoplankton distribution was closely related to salinity gradients, nutrient levels, and water residence time. Microscopic analysis revealed that phytoplankton was composed mainly of marine diatoms, dinoflagellates, cryptophytes, green flagellates, and coccolithophorids. The dominant biomarker pigments were fucoxanthin, alloxanthin and 19'-hexanoyloxyfucoxanthin, while lower, but indicative contributions of peridinin and chlorophyll b were also noted. Maximum abundance and biomass were found in the middle estuary in winter and in the upper estuary in summer. The estuary is mostly P-limited. Development of chain-forming marine diatoms was evident in winter. Due to the reduced nutrient input in summer, the biomass accumulated in the upper estuary (1,000 ng chlorophyll a l(-1)) was composed mostly of nanoplanktonic unicellular diatoms, nanoplanktonic marine dinoflagellates, cryptophytes, and chlorophytes. The concentrations of about 200 ng l(-1) hex-fuco, suggested that the contribution of prymnesiophytes to total biomass was comparable to that of diatoms and dinoflagellates. In the middle estuary and coastal sea, PO(4) and TIN were 3.5 times lower, resulting in a fivefold decrease in biomass (<100 ng chlorophyll a l(-1)). The oligotrophic Zrmanja and other karstic rivers discharging in the eastern Adriatic Sea, provide insufficient source of nutrients and low productivity of the eastern Adriatic Sea. 相似文献
697.
Dubravka Relić Dragana Đorđević Aleksandar Popović Milka Jadranin Predrag Polić 《Environmental monitoring and assessment》2010,171(1-4):229-248
Thirty-five alluvial sediments of the River Danube and 12 groundwater samples were taken within the Pan?evo Oil Refinery (Serbia). The results for groundwater samples exceed European primary drinking water standards for Fe (obtained results, >200 μg/l) and Mn (obtained results, >50 μg/l), while the levels of the trace metals are below the thresholds for drinking water quality. Sediments were treated by sequential extraction procedure with five different solutions, each having a higher extraction capacity than the previous one. We also wanted to determine the possible relationships among trace metals and between sediment properties and elemental concentrations. These solutions partitioned metals into CH3COONH4 extractable (F1); HCl carbonate extractable and NH2OH·HCl easily reducible (F2); (NH4)2C2O4/H2C2O4 moderately reducible (F3); H2O2–HNO3 organic/sulfide extractable fractions (F4); and HCl acid-soluble residue (F5). The sum of trace metals Ni, Pb, Cu, and Zn associated with the first two fractions (exchangeable, carbonate, and easily reducible) is significant and extremely important because it represents the proportion of heavy metals that can be easily remobilized by changes in environmental conditions such as pH, redox potential, salinity, etc. Sediments located nearer the groundwater flow are exposed to stronger groundwater fluctuation and had a higher quantity of amorphous and less stable substrates of trace metals. Principal component analysis was used to understand and visualize the associations between the trace metals and certain geological forms within analyzed sediments. The observed association between Cr with total sulfur and Mn from the acid-soluble residue could indicate that Cr is in the form of reduced, less toxic Cr(III), which is from the ecochemical point of view very important. 相似文献
698.
Stambuk-Giljanović N 《Environmental monitoring and assessment》2008,140(1-3):109-117
The objective of this paper is to study the hydrological characteristics and origin of the hydrogen sulphide spring water
from the Split spa in Southern Croatia in 1987, 1988 and 2003. This paper presents the results of monitoring the content of
chlorides and hydrogen sulphide as well as the temperature of the hydrogen sulphide spring water. Since the hydrogen sulphide
content during the dry periods significantly differs from the hydrogen sulphide content during rainy periods, this paper also
compares the results obtained for those two periods. Under the influence of great quantities of rainfall during cold periods
(winter and the beginning of spring) the ratio between seawater and surface water changes and thus the reduction of chlorides
and other minerals occurs. The lowered temperature also reduces hydrogen sulphide which can disappear completely. The concentration
of 12‰ chlorides (76–94.4% days/year) and 12 mg/L hydrogen sulphide (66.7–88.9% days/year) has been taken as a limit value
between water with a normal typical content and water in cold rainy periods. According to the monitoring results it can be
concluded that hydrogen sulphide spring water consists of seawater and hydrogencarbonate surface water with a fairly constant
content during dry periods while the hydrogencarbonate content increases during rainy periods. 相似文献
699.
Analysis of mosses and topsoils for detecting sources of heavy metal pollution: multivariate and enrichment factor analysis 总被引:2,自引:0,他引:2
In order to assess the contribution of emission sources to the pollution of areas remote from industrial facilities, a combined approach of enrichment factor analysis and multivariate statistics was used for detecting the origin of heavy metal pollution in the Zlatibor ecosystem, in Serbia. Samples of moss (Pleurozium schreberi, Hylocomium splendens, Scleropodium purum, Hypnum cupressiforme and Thuidum delicatulum) and of topsoil (0-5 cm) were collected in 2005. The concentrations of seven heavy metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) were determined in moss and soil samples by atomic absorption spectrometry. The results obtained by enrichment factor analysis and two multivariate statistical methods, principal component analysis and cluster analysis, enabled discrimination of the lithologic and anthropogenic sources of heavy metals in the mosses. Enrichment factors, calculated to evaluate the contribution to the metal content in moss from anthropogenic sources, revealed pollution of the investigated area by Cd and Pb, originating from long-range transport and fossil fuel burning. 相似文献
700.
Araújo Leylia K. F. Albuquerque Allan A. Ramos Weslley C. O. Santos Alef T. Carvalho Sandra H. V. Soletti João I. Bispo Mozart D. 《Environment, Development and Sustainability》2021,23(8):11732-11750
Environment, Development and Sustainability - The activated biochar is a carbonaceous material obtained from thermal degradation of biomass with high adsorption potential. On the other hand, the... 相似文献