全文获取类型
收费全文 | 3021篇 |
免费 | 27篇 |
国内免费 | 37篇 |
专业分类
安全科学 | 90篇 |
废物处理 | 157篇 |
环保管理 | 326篇 |
综合类 | 526篇 |
基础理论 | 640篇 |
环境理论 | 3篇 |
污染及防治 | 861篇 |
评价与监测 | 264篇 |
社会与环境 | 197篇 |
灾害及防治 | 21篇 |
出版年
2023年 | 40篇 |
2022年 | 94篇 |
2021年 | 124篇 |
2020年 | 66篇 |
2019年 | 60篇 |
2018年 | 113篇 |
2017年 | 115篇 |
2016年 | 144篇 |
2015年 | 89篇 |
2014年 | 136篇 |
2013年 | 187篇 |
2012年 | 147篇 |
2011年 | 195篇 |
2010年 | 131篇 |
2009年 | 123篇 |
2008年 | 134篇 |
2007年 | 120篇 |
2006年 | 90篇 |
2005年 | 121篇 |
2004年 | 158篇 |
2003年 | 154篇 |
2002年 | 100篇 |
2001年 | 76篇 |
2000年 | 34篇 |
1999年 | 35篇 |
1998年 | 17篇 |
1997年 | 26篇 |
1996年 | 17篇 |
1995年 | 22篇 |
1994年 | 18篇 |
1993年 | 9篇 |
1992年 | 12篇 |
1991年 | 17篇 |
1990年 | 10篇 |
1989年 | 11篇 |
1988年 | 6篇 |
1987年 | 10篇 |
1986年 | 8篇 |
1985年 | 10篇 |
1984年 | 10篇 |
1983年 | 11篇 |
1982年 | 5篇 |
1981年 | 7篇 |
1979年 | 8篇 |
1977年 | 3篇 |
1975年 | 3篇 |
1970年 | 4篇 |
1966年 | 3篇 |
1964年 | 4篇 |
1961年 | 3篇 |
排序方式: 共有3085条查询结果,搜索用时 12 毫秒
91.
A sustainable future for olive production on sloping land? 总被引:1,自引:0,他引:1
92.
In Ireland, dairy farmyard washwater commonly comprises farmyard run-off and dairy parlour washings. Land-spreading is the most widely used method for treating this wastewater. However, this method can be labour intensive and can cause, in some cases, the degradation of surface and ground waters, mainly due to nitrogen contamination. In this study, a horizontal flow biofilm reactor (HFBR) with step-feed was constructed and tested in the laboratory, to remove organic carbon and nitrogen from a agricultural strength synthetic washwater (SWW). The HFBR had an average top plan surface area (TPSA) of 0.1002 m(2) and consisted of a stack of 45 polystyrene horizontal sheets--15 sheets embedded with 25 mm deep frustums above 30 sheets with 10 mm deep frustums. The frustums acted as miniature reservoirs. The sheets were alternately offset to allow the wastewater to flow horizontally along each sheet and vertically from sheet to sheet down through the reactor. Biofilms developed on the sheets and treated the wastewater. During the 212-d study, the total hydraulic loading rate based on the TPSA of the sheets was 35 l m(-2) d(-1). SWW was pumped for 10 min each hour, in a step feed arrangement at a rate of 23.33 l m(-2) d(-1) on to the top sheet during Phases 1 and 2, and 11.67 l m(-2) d(-1) onto Sheet 16 during Phase 1 (days 1-92) and onto Sheet 30 during Phase 2 (days 93-212). The substrate loading rate during Phases 1 and 2 was 94.8 g total chemical oxygen demand (COD) m(-2) d(-1) and 10.5 g total nitrogen (TN) m(-2) d(-1), based on the TPSA. At steady state in Phase 2, the unit achieved excellent carbon removal of 99.7% 5-day biochemical oxygen demand (BOD(5)) and 96.7% total COD, equivalent to TPSA removal rates of 67.5 g BOD(5)m(-2)d(-1) and 91.7 g COD m(-2) d(-1). The nitrogen removal percentages were 98.3% total ammonium-nitrogen (NH(4)-N(t)) and 72.8% TN, which equated to TPSA removal rates of 4.8 g NH(4)-N(t) m(-2) d(-1) and 7.6g TN m(-2) d(-1). No sloughing of solids or clogging of media occurred during the study. The unit was simple to construct and operate, with little maintenance. 相似文献
93.
94.
Sónia?Roxo José?António?de?AlmeidaEmail author Filipa?Vieira?Matias Herlander?Mata-Lima Sofia?Barbosa 《Environmental monitoring and assessment》2016,188(3):129
This paper proposes a multistep approach for creating a 3D stochastic model of total petroleum hydrocarbon (TPH) grade in potentially polluted soils of a deactivated oil storage site by using chemical analysis results as primary or hard data and classes of sensory perception variables as secondary or soft data. First, the statistical relationship between the sensory perception variables (e.g. colour, odour and oil–water reaction) and TPH grade is analysed, after which the sensory perception variable exhibiting the highest correlation is selected (oil–water reaction in this case study). The probabilities of cells belonging to classes of oil–water reaction are then estimated for the entire soil volume using indicator kriging. Next, local histograms of TPH grade for each grid cell are computed, combining the probabilities of belonging to a specific sensory perception indicator class and conditional to the simulated values of TPH grade. Finally, simulated images of TPH grade are generated by using the P-field simulation algorithm, utilising the local histograms of TPH grade for each grid cell. The set of simulated TPH values allows several calculations to be performed, such as average values, local uncertainties and the probability of the TPH grade of the soil exceeding a specific threshold value. 相似文献
95.
Ana Carolina Feitosa Cruz Marcela Bergo Davanso Giuliana Seraphim Araujo Lucas M. Buruaem Sandra Tédde Santaella Rodofley Davino de Morais Denis M. S. Abessa 《Environmental monitoring and assessment》2014,186(11):7035-7046
This study aimed to evaluate the sediment quality in the estuarine protected area known as Cananéia-Iguape-Peruíbe (CIP-PA), located on the southeastern coast of Brazil. The study was designed considering possible negative effects induced by the city of Cananéia on the sediment quality of surrounding areas. This evaluation was performed using chemical and ecotoxicological analyses. Sediments were predominantly sandy, with low CaCO3 contents. Amounts of organic matter varied, but higher contents occurred closer to the city, as well as did Fe and Total Recoverable Oils and Greases (TROGs) concentrations. Contamination by Cd and Cu was revealed in some samples, while concentrations of Zn were considered low. Chronic toxicity was detected in all tested sediments and acute toxicity occurred only in sediments collected near the city. The principal component analysis (PCA) revealed an association among Cd, Cu, Fe, TROG, fines, organic matter, CaCO3, and chronic toxicity, whereas acute toxicity was found to be associated with Zn and mud. However, because Zn levels were low, acute toxicity was likely due to a contaminant that was not measured. Results show that there is a broad area within the CIP-PA that is under the influence of mining activities (chronic toxicity, moderate contamination by metals), whereas poorer conditions occur closer to Cananéia (acute toxicity); thus, the urban area seems to constitute a relevant source of contaminants for the estuarine complex. These results show that contamination is already capable of producing risks for the local aquatic biota, which suggests that the CIP-PA effectiveness in protecting estuarine biota may be threatened. 相似文献
96.
AA Carbonell-Barrachina A Ramírez-Gandolfo X Wu GJ Norton F Burló C Deacon AA Meharg 《Journal of environmental monitoring : JEM》2012,14(9):2447-2455
Spanish gluten-free rice, cereals with gluten, and pureed baby foods were analysed for essential macro-elements (Ca and Na), essential trace elements (Fe, Cu, Zn, Mn, Se, Cr, Co and Ni) and non-essential trace elements (As, Pb, Cd and Hg) using ICP-MS and AAS. Baby cereals were an excellent source of most of the essential elements (Ca, Fe, Cu, Mn and Zn). Sodium content was high in pureed foods to improve their flavour; fish products were also rich in Se. USA pure baby rice samples had the highest contents of all studied essential elements, showing a different nutrient pattern compared to those of other countries. Mineral fortification was not always properly stated in the labelling of infant foods. Complementary infant foods may also contain significant amounts of contaminants. The contents of Hg and Cd were low enough to guarantee the safety of these infant foods. However, it will be necessary to identify the source and reduce the levels of Pb, Cr and As in Spanish foods. Pure baby rice samples contained too much: Pb in Spain; As in UK; As, Cr and Ni in USA; and Cr and Cd in China. 相似文献
97.
98.
de Figueiredo DR Ferreira RV Cerqueira M de Melo TC Pereira MJ Castro BB Correia A 《Environmental monitoring and assessment》2012,184(1):471-485
The information on bacterial community composition (BCC) in Portuguese water bodies is very scarce. Cértima River (central
western Portugal) is known to have high levels of pollution, namely organic. In the present work, the BCC from a set of 16
water samples collected from Cértima River Basin and its main tributaries was characterized using 16S rDNA–denaturing gradient
gel electrophoresis, a culture-independent molecular approach. Molecular data were related to environmental parameters through
multivariate analysis to investigate potential impact of water pollution along the river. Principal component analysis using
environmental data showed a water quality gradient from more pristine waters (at the mountain tributaries) to waters with
increasingly eutrophic potential (such as Fermentelos Lake). This gradient was mainly defined by factors such as organic and
inorganic nutrient sources, electrical conductivity, hydrogen carbonate concentration, and pH. Molecular results showed variations
in BCC along Cértima River Basin but in the main river section, a Bacteroidetes phylotype (Flavobacterium sp.) proved to be dominant throughout the river course. Multivariate analysis suggests that spatial variation of BCC along
the Cértima River Basin depended mainly on parameters such as Chl a, total suspended solid (TSS), total organic carbon, electrical conductivity, and HCO
_boxclose^-_{3}^{-} levels. Bacteroidetes phylotypes were all related to higher electrical conductivity and HCO3-_{3}^{-} levels although some of these were also correlated with high SO42-_{4}^{2-} and others with high soluble reactive phosphorus, nitrate, TN, and Kjeld-N levels. The Gammaproteobacteria occurrence was correlated with high SO42-_{4}^{2-} levels. One of the Betaproteobacteria phylotypes showed to correlate with low redox potential (Eh) and high temperature, pH, TSS, and Chl a levels while another one showed a negative correlation with Chl a values. 相似文献
99.
de Andrade Brito I Arruda Freire C Yamamoto FY Silva de Assis HC Rodrigues Souza-Bastos L Cestari MM de Castilhos Ghisi N Prodocimo V Filipak Neto F de Oliveira Ribeiro CA 《Journal of environmental monitoring : JEM》2012,14(2):615-625
Paraíba do Sul River is located at a very densely inhabited region of Brazil crossing the three most industrialized states of the country (S?o Paulo, Minas Gerais and Rio de Janeiro states). As a result, industrial and farming residues as well as urban sewage are frequently disposed without appropriate treatment. The current study aimed at investigating the water quality in three reservoirs along the Paraíba do Sul River (Ilha dos Pombos, Santa Cecília and Santa Branca), through physiological, morphological, biochemical, and genetic biomarkers. The bioindicator chosen was the catfish Pimelodus maculatus, sampled during the dry (June 2008) and rainy (February 2009) seasons. Also, some water physicochemical parameters were analyzed from the sampling sites, but displayed no alterations according to the Brazilian Agency for Water Quality Legislation. Branchial carbonic anhydrase activity was inhibited in the dry season, while renal carbonic anhydrase activity was inhibited in the rainy season in the Santa Branca reservoir, indicating disturbance of osmoregulatory and acid-base regulation processes. Histopathological alterations were observed in the gills (neoplasic and tissue hyperplasia processes) and liver (necrosis), indicating serious damage to the functional integrity of these organs. A high incidence of melanomacrophage centers was observed in the liver, suggesting an intense immune response in all reservoirs. Acetylcholinesterase and catalase activity showed also differences corroborating some morphological results. Likewise, the induction of the micronucleus and DNA damage indicate genotoxicity, but mainly in the Santa Branca reservoir. Thus, the health status of P. maculatus warrants caution in the use of the water from the 3 reservoirs for direct human consumption, particularly after the accidental spill of endosulfan in November 2008, three months before the rainy season sampling. 相似文献
100.
Nédia de Castilhos Ghisi Marta Margarete Cestari 《Environmental monitoring and assessment》2013,185(4):3201-3207
The glyphosate-based herbicide, Roundup®, is one of the most used pesticides worldwide. In concert with the advent of transgenic crops resistant to glyphosate, the use of this pesticide has led to an increase in agricultural yields. The objective of this study was to evaluate the genotoxic effect that the herbicide Roundup® (at a concentration of 6.67 μg/L, corresponding to 3.20 μg/L glyphosate) can have on the fish Corydoras paleatus. Treatment groups were exposed for 3, 6, and 9 days, and effects were analyzed using the piscine micronucleus test (PMT) and comet assay. A group subjected to filtered water only was used as a negative control. The PMT did not show differences between the control and exposed groups for any of the treatment times. In contrast, the comet assay showed a high rate of DNA damage in group exposed to Roundup® for all treatment times, both for blood and hepatic cells. We conclude that for the low concentration used in this research, the herbicide shows potential genotoxic effects. Future research will be important in evaluating the effects of this substance, whose presence in the environment is ever-increasing. 相似文献