首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   163篇
  免费   2篇
  国内免费   4篇
安全科学   3篇
废物处理   4篇
环保管理   15篇
综合类   43篇
基础理论   32篇
环境理论   1篇
污染及防治   38篇
评价与监测   10篇
社会与环境   22篇
灾害及防治   1篇
  2023年   1篇
  2022年   1篇
  2021年   3篇
  2020年   3篇
  2019年   1篇
  2018年   6篇
  2017年   6篇
  2016年   10篇
  2015年   8篇
  2014年   7篇
  2013年   13篇
  2012年   9篇
  2011年   12篇
  2010年   5篇
  2009年   12篇
  2008年   7篇
  2007年   11篇
  2006年   10篇
  2005年   10篇
  2004年   5篇
  2003年   8篇
  2002年   7篇
  2000年   1篇
  1998年   1篇
  1995年   1篇
  1994年   1篇
  1993年   1篇
  1992年   2篇
  1991年   1篇
  1990年   1篇
  1984年   1篇
  1977年   1篇
  1971年   1篇
  1961年   1篇
  1959年   1篇
排序方式: 共有169条查询结果,搜索用时 15 毫秒
1.
Environmental Fluid Mechanics - A 3D dry deposition scheme for particulate matter (PM) is presented as a Free-Libre and Open-Source Software (FOSS) library, DePaSITIA (RSE SpA). This combines some...  相似文献   
2.
The biodegradability of a multicomponent system based on biotechnological occurring polyester (poly(-hydroxybutyrate-co--hydroxyvalerate) (PHBV)) with inclusion of acrylate elastomer (polybutylacrylate) (PBA) was investigated. A bacterium which produced extracellular enzymes that degrades PHBV even when blended with PBA was isolated and tentatively designated asAureobacterium saperdae. It was observed, by morphological investigation, that, while the bacterial degradation was permitted for PBA content of 20% by weight, it was inhibited for PBA content of 30%, owing to the occurrence of a rubbery layer that prevents to the bacteria an easy accessibility in the PHBV-rich regions. In fact, owing the bacterial growth, only PHBV was metabolized, whereas no degradation of PBA was detected for blend samples. It was confirmed that the degradation proceeded via surface erosion of PHBV also in the blends. Finally, mechanical tests on PHBV/PBA specimens as a function of degradation extent have shown different behavior of the blends at different the PBA content. Thermal analysis of blends and PHBV has been reported, too  相似文献   
3.
Prenatal diagnosis of heterozygous achondroplasia at 25 weeks is described. First-level fetal ultrasonography demonstrated short long bones of the lower limbs. Second-level examination showed a large head; shortened femur, fibula, and tibia; a ‘trident’-shaped hand; and an abnormal facial profile.  相似文献   
4.
Regional Environmental Change - The spread of non-native species into natural communities is a noticeable phenomenon linked to global change. Drivers of such invasions, however, may differ...  相似文献   
5.
n-Alkanes and polycyclic aromatic hydrocarbons (PAHs) bound to atmospheric particulate matter (PM1) were investigated in a traffic site located in an urban area of Venice Province (Eastern Po Valley, Italy) during the cold season. Considering the critical situation affecting the Veneto Region concerning the atmospheric pollution and the general lack of information on PM1 composition and emission in this area, this experimental study aims at determining the source profile, their relative contributions and the dispersion of finer particles. Four sources were identified and quantified using the Positive Matrix Factorization receptor model: (1) mixed combustions related to the residential activities, (2) agricultural biomass burning in addition to the resuspension of anthropogenic and natural debris carried by the wind, (3) gasoline and (4) diesel traffic-related combustions. The role of local atmospheric circulation was also investigated to identify the pollutant sources.  相似文献   
6.
Accurate knowledge of the quality and environmental impact of the highway runoff in Pear River Delta, South China is required to assess this important non-point pollution source. This paper presents the quality characterization and environmental impact assessment of rainfall runoff from highways in urban and rural area of Guangzhou, the largest city of Pear River Delta over 1 year’s investigation. Multiple regression and Pearson correlation analysis were used to determine influence of the rainfall characteristics on water quality and correlations among the constituents in highway runoff. The results and analysis indicates that the runoff water is nearly neutral with low biodegradability. Oil and grease (O&G), suspended solids (SS) and heavy metals are the dominant pollutants in contrast to the low level of nutrient constituents in runoff. Quality of highway runoff at rural site is better than that of at urban site for most constituents. Depth and antecedent dry period are the main rainfall factors influencing quality of highway runoff. The correlation patterns among constituents in highway runoff at urban site are consistent with their dominant phases in water. Strong correlations (r ≥ 0.80) are found among chemical oxygen demand (COD), total phosphorus, Cu and Zn as well as conductivity, nitrate nitrogen and total nitrogen. O&G, COD, SS and Pb in highway runoff at urban site substantially exceed their concentrations in receiving water of Pear River. The soil directly discharged by highway runoff at rural site has contaminated seriously by heavy metals in surface layer accompanying with pH conversion from original acidic to alkaline at present.  相似文献   
7.
Successful remediation of contaminated soils is often limited by the low bioavailability of hydrophobic pollutants, which may slow the process significantly. In this study we investigated the benefits of high temperature in enhancing hydrocarbon degradation rates and evaluated the effect of different biostimulants. Hexadecane polluted soil microcosms with various amendments were incubated both at 60 degrees C and room temperature (18 degrees C) and analyzed periodically up to 40d for the degradation of hydrocarbon and the response of the microbial population. Natural attenuation showed a satisfactory intrinsic degradative capability at 60 degrees C and the addition of inorganic N, P and K increased the degradation rates by 10%. The addition of rhamnolipid biosurfactant further enhanced the bioavailability of alkane to microbial degradation resulting in up to 71% removal at 60 degrees C and 42% at 18 degrees C. Significant input to hexadecane degradation occurred at 60 degrees C (70%) as a result of the bioaugmentation with thermophilic Geobacillus thermoleovorans T80, which did not take place at 18 degrees C. Coupling high temperature to all amendments resulted in 90% removal of the hexadecane from soil after 40d which was also accompanied with an increase in bacterial numbers. The results suggest that thermally enhanced bioremediation may be an efficient technology for the treatment of hydrocarbon-contaminated soils.  相似文献   
8.
The river Lambro is the most polluted tributary of the river Po in North Italy and was chosen as a representative water course discharging industrialized areas. Water and sediment samples of the river Lambro were investigated regarding the presence of endocrine disrupting compounds. A combined procedure was used consisting of solid-phase extraction and HPLC based fractionation of samples, of screening for (anti)androgenic activity using the yeast androgen screen (YAS) and of chemical analysis using HPLC-MS/MS and GC-MS. Androgenic and antiandrogenic activities were found in specific fractions of the water and sediment while the total extracts showed antiandrogenic activity only. The chemical analysis of the fractions and total extracts with antiandrogenic activities revealed the presence of compounds with suspected antiandrogenic potency such as bisphenol A, iprodione, nonylphenol, p,p'-DDE and tert-octylphenol but other unknown compounds contributed mainly to the observed antiandrogenic activities. The antiandrogenic load of the river Lambro ranged between 1.34 and 17.1 microM flutamide-equivalents and may pose a risk to aquatic environments. Future screenings for EDC in the environment that have the potential to interfere with reproduction of aquatic organisms should be extended to different modes of actions including (anti)androgenic ones.  相似文献   
9.
Fenamidone is an imidazolinone fungicide recently introduced in viticulture practices. This work reports the validation and assessment of global uncertainty of a gas chromatographic with mass spectrometry method to analyze fenamidone in grapes and wines. This method consists in a simple and fast liquid-liquid extraction step followed by chromatographic determination. Limits of detection for fenamidone in grapes and wines were, respectively, 0.05 mg/kg and 0.06 mg/L, precision was below 9.4% and average recovery was 89 +/- 5%. In the concentration range from 0.05 to 1.00 mg/kg (or mg/L) of fenamidone, global uncertainty calculated following the EURACHEM/CITAC rules, and also by the Horwitz function, was below 25%. The EURACHEM/CITAC global uncertainty budget used gave lower estimates than those obtained from the Horwitz function.  相似文献   
10.
In order to characterize the different sources of exposure to arsenic (As), urinary excretion of total As, the sum of inorganic As+MMA+DMA determined by the hydride generation-atomic absorption spectrophotometry technique, and the species As(3), As(5), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and arsenobetaine were determined in 49 workers at a steel foundry, with presumed occupational exposure to As, and 50 subjects from the general population, all males. No evidence of occupational exposure to As resulted from environmental monitoring performed in the foundry, although the analysis of minerals used as raw materials showed the presence of As, particularly in fossils and fine ores. The urinary concentrations of As(3), MMA, DMA, the sum of inorganic As+MMA+DMA and total As were not different in the two groups, while arsenobetaine appeared significantly higher in the controls than in the workers. The different species of urinary As were all significantly correlated. Urinary excretion of As(3) was associated with the consumption of mineral water and with residence in an industrial zone, while MMA, DMA, arsenobetaine, the sum of inorganic As+MMA+DMA and total As urinary excretion were associated with the consumption of crustaceans and/or shellfish 3 days or less before urine collection. Multiple regression analysis confirmed these results. In conclusion, in populations with a high consumption of seafood, living in areas characterized by coastal/marine As pollution, only speciation of As can identify a prevalent role of environmental sources, like the consumption of seafood contaminated by As, in determining urinary As excretion, and exclude an occupational origin of the exposure.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号