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   126篇
  免费   2篇
  国内免费   4篇
安全科学   5篇
废物处理   5篇
环保管理   10篇
综合类   31篇
基础理论   28篇
污染及防治   38篇
评价与监测   9篇
社会与环境   6篇
  2023年   5篇
  2022年   6篇
  2021年   4篇
  2020年   2篇
  2019年   4篇
  2018年   6篇
  2017年   1篇
  2016年   12篇
  2015年   8篇
  2014年   14篇
  2013年   7篇
  2012年   15篇
  2011年   10篇
  2010年   9篇
  2009年   6篇
  2008年   5篇
  2007年   5篇
  2006年   4篇
  2005年   6篇
  2003年   1篇
  1998年   1篇
  1995年   1篇
排序方式: 共有132条查询结果,搜索用时 31 毫秒
61.
This study reports a general assessment of the organic composition of the PM2.5 samples collected in the city of Augsburg, Germany in a summer (August-September 2007) and a winter (February-March 2008) campaign of 36 and 30 days, respectively. The samples were directly submitted to in-situ derivatisation thermal desorption gas chromatography coupled with time of flight mass spectrometry (IDTD-GC-TOFMS) to simultaneously determine the concentrations of many classes of molecular markers, such as n-alkanes, iso- and anteiso-alkanes, polycyclic aromatic hydrocarbons (PAHs), oxidized PAHs, n-alkanoic acids, alcohols, saccharides and others.The PCA analysis of the data identified the contributions of three emission sources, i.e., combustion sources, including fossil fuel emissions and biomass burning, vegetative detritus, and oxidized PAHs. The PM chemical composition shows seasonal trend: winter is characterized by high contribution of petroleum/wood combustion while the vegetative component and atmospheric photochemical reactions are predominant in the hot season.  相似文献   
62.
Several species of seagrass and marine macrophytes were investigated for their biosorption performance in the removal of lead from aqueous solution. The effect of pH on the equilibrium of the seagrass Cymodocea nodosa as a biosorbent also was studied. It was found that increasing pH increased lead biosorption, with a maximum uptake of approximately 140 mg/g in the range pH 3.3 to 5. Equilibrium data at different pH levels were successfully fitted to competitive equilibrium models. In addition, the seaweeds belonging to different phyla (i.e., Chlorophyta, Heterokontophyta, and Rhodophyta) were studied for the effect of their structure on equilibrium at a constant pH 5. The brown algae (Heterokontophyta) showed the highest potential for lead sorption, with a maximum uptake of 220 mg/g for C. compressa and 140 mg/g for S. lomentaria. The green algae (Chlorophyta) showed lead uptake in the range 40 to 90 mg/g, and the red algae (Rhodophyta) was least effective, with uptake in the range 10 to 40 mg/g.  相似文献   
63.
Genetic differences in the Posidonia oceanica meadow of Monterosso al Mare (NW Mediterranean, Marine Protected Areas (MPAs) "Cinque Terre") were compared in three stations, at an increasing distance from a source of impact (beach nourishment) in the recent decade. Random amplified polymorphic DNA analysis showed a higher genetic variability (>20?%) in the area directly subjected to the stress, increasing with time. Clone integration, confirmed by phenotypic analysis, showed increases both in shoot density and leaf length connected to genetic differences observed in DNA fingerprints of new shoots. Analysis of molecular variance (AMOVA) showed 45?% individual differences within populations and 54?% among the populations. The fixation index (F (ST)?=?0.54), of the genetic differentiation, showed a marked difference between the populations at different temporal scales. Over a decade AMOVA indicated genetic variations from 28?% (1998) to 54?% (2009). These results make it clear that in the P. oceanica population examined the environment had, in ten years, selected those clones which were more resistant to the anthropogenic impact, despite being subjected to the effects of the resuspension of fine sediments. These findings could help to explain both the survival of the regressed Mediterranean P. oceanica meadows in areas subjected to moderate impacts and the extreme variability in success of revegetation experiments. Management of the ecological disturbance here described indicates also the timescale in population response to stress and its increased resilience in MPAs.  相似文献   
64.
The cathode ray tube (CRT) glass is one of the most important problem that afflicts the electronic waste disposal whose solution lies in the identification of efficient and ecofriendly processes to detoxify and reutilize lead-contained funnel glass. This study is focused on a rapid screening of different chemical and mechanochemical processes to reduce lead content in waste CRT glass downgrading the risk correlated to it. In particular, as a possibility to clean waste CRT glass, treatments of lead-containing glass with different chelating agents (EDTA, NTA, ATMP, EDTMP and HEDP) were performed to evaluate their extractive capabilities. Furthermore, the influence of the grinding, the chelating agent functional groups (polyamino-carboxylic acid, carboxylic acid, and polyamino phosphonic acid), and the time and the temperature on lead content reduction were analyzed. ESEM and EDS analysis were performed on all the samples to evaluate the lead amount before and after the treatments.  相似文献   
65.
PM10 levels have been recorded in the suburban area of Caserta (Italy) from February to October 2012. The daily limit was exceeded in 13 % of the determinations, with no significant difference between weekdays and weekends. Benzo[a]pyrene concentrations were in the range 0.01–0.46 ng/m3, thus, never exceeding the National Standard. The B(a)P-eq was 0.20 ng/m3. PM10 peaks were associated with wind from east–northeast. The same was observed for Ca concentrations, whereas no relation with wind direction was observed for organic pollutants. The results point to a local limestone quarry and cement factory as the likely major source of PM10 pollution in the area investigated.  相似文献   
66.
- DOI: http://dx.doi.org/10.1065/espr2006.01.004 Background, Aim and Scope Environmental contamination by pharmaceuticals is an emerging issue. Until recently, information on medicinal substances released into the environment was scant, but several studies have now been published. Data are, however, usually scattered and a systematic approach to this subject is generally lacking. Moreover, because of differences in the prevalence of diseases, treatment habits and options, or simply for market reasons, the pollution profile can differ significantly in different countries. The aim of this work is to review the papers dealing with environmental contamination by pharmaceuticals in Italy, with the aim of providing a comprehensive view on a national scale. Methods Papers related to environmental contamination by pharmaceuticals in Italy were reviewed, in order to offer a comprehensive view of this subject. Topics included analysis, occurrence, monitoring, modelling, treatment, control of the emissions, and ecotoxicological effects of pharmaceuticals in the environment. Results and Conclusion The literature suggests that pharmaceuticals are widespread contaminants, entering the environment from a myriad of scattered points. Patients, in case of drugs for human use, or animals for veterinary drugs, are the main sources of contamination. Pharmaceuticals can be ranked according to environmental loads, predicted by multiplying sales figures by the rate of metabolism in man or animals. Priority pharmaceuticals, i.e. the molecules of concern for the environment, can be measured in waste and surface water by liquid chromatography-tandem mass spectrometry, and the loads detected are generally comparable to the predicted ones. Pharmaceuticals are designed to stimulate a response in humans and animals at low doses, with a very specific target, so the implications for human health and the environment need to be assessed. In vitro and in vivo studies suggest that pharmaceutical principles, taken singularly or in combinations, and concentrations close to those detected in the environment, may have ecotoxicological effects. The sewage system is an important point in the control of contamination, but sewage treatment plants are not able efficiently to abate a substantial part of water-borne pharmaceuticals. Several variables play a role, however, in the processes of waste water treatment, and could be specifically adjusted to improve the efficiency of drug abatement, mitigating the potential environmental hazards. Recommendation and Perspective Pharmaceuticals in the environment are becoming a subject of global concern, with potential environmental consequences. Further knowledge of the causes, occurrence and effects of drugs as environmental pollutants is necessary for a better understanding of this ecological issue, as well as to improve abatement strategies, and to mitigate subtle environmental consequences.  相似文献   
67.
68.
69.
While both sperm number and quality are now recognized to be important in determining the outcome of sperm competition, very few studies have experimentally assessed the influence of these two parameters simultaneously. We studied the effect of sperm quality and number on competitive fertilization success in an internal-fertilizing fish, the guppy (Poecilia reticulata), which is characterized by high levels of sperm competition. We artificially inseminated virgin females with varying proportion of sperm from two competing males, while holding constant the total number of sperm transferred to the female. Sperm morphology and sperm swimming velocity were also determined prior to insemination. The paternity outcome of sperm competition trials was assessed through molecular analyses of the resulting offspring using polymorphic microsatellite loci. We found that both sperm number and sperm velocity affected the outcome of sperm competition, with males that contributed more and faster sperm achieving a greater paternity share.  相似文献   
70.
Hepatitis A virus (HAV) was detected in two samples of mixed frozen berries linked to Italian hepatitis A outbreak in April and September 2013. Both viruses were fully sequenced by next-generation sequencing and the genomes clustered with HAV complete genomes of sub-genotype IA with nucleotide identities of 95–97 %.  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