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   205篇
  免费   2篇
安全科学   7篇
废物处理   12篇
环保管理   7篇
综合类   41篇
基础理论   34篇
污染及防治   66篇
评价与监测   33篇
社会与环境   6篇
灾害及防治   1篇
  2023年   4篇
  2022年   5篇
  2021年   9篇
  2020年   1篇
  2019年   4篇
  2018年   3篇
  2017年   11篇
  2016年   12篇
  2015年   5篇
  2014年   19篇
  2013年   32篇
  2012年   5篇
  2011年   8篇
  2010年   18篇
  2009年   8篇
  2008年   8篇
  2007年   5篇
  2006年   6篇
  2005年   3篇
  2004年   2篇
  2003年   2篇
  2002年   2篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1997年   1篇
  1995年   1篇
  1994年   1篇
  1991年   2篇
  1987年   2篇
  1985年   1篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
  1970年   2篇
  1969年   1篇
  1967年   1篇
  1966年   1篇
  1964年   2篇
  1961年   1篇
  1960年   2篇
  1959年   1篇
  1958年   3篇
  1957年   2篇
  1956年   1篇
  1955年   1篇
  1954年   2篇
排序方式: 共有207条查询结果,搜索用时 46 毫秒
101.
Landfill leachate (LL) usually contains low concentrations of heavy metals due to the anaerobic conditions in the methanogenic landfill body after degradation of easily degradable organic matter and the neutral pH of LL, which prevents mobilization and leaching of metals. Low average concentrations of metals were also confirmed in our extensive study on the rehabilitation of an old landfill site with vegetative landfill cover and LL recirculation after its treatment in constructed wetland. The only exception was chromium (Cr). Its concentrations in LL ranged between 0.10 and 2.75 mg/L, and were higher than the concentrations usually found in the literature. The objectives of the study were: (1) to understand why Cr is high in LL and (2) to understand the fate and transport of Cr in soil and vegetation of landfill cover due to known Cr toxicity to plants. The total concentration of Cr in LL, total and exchangeable concentrations of Cr in landfill soil cover and Cr content in the plant material were extensively monitored from May 2004 to September 2006. By obtained data on Cr concentration in different landfill constituents, supported with the data on the amount of loaded leachate, amount of precipitation and potential evapotranspiration (ETP) during the performance of the research, a detailed picture of time distribution and co-dependency of Cr is provided in this research. A highly positive correlation was found between concentrations of Cr and dissolved organic carbon (r = 0.875) in LL, which indicates the co-transport of Cr and dissolved organic carbon through the system. Monitoring results showed that the substrate used in the experiment did not contribute to Cr accumulation in the landfill soil cover, resulting in percolation of a high proportion of Cr back into the waste layers and its circulation in the system. No negative effects on plant growth appeared during the monitoring period. Due to low uptake of Cr by plants (0.10–0.15 mg/kg in leaves and 0.05–0.07 mg/kg in stems of Salix purpurea), the estimated Cr offtake from LL by plants represented only a small proportion of the LL Cr mass load during the observation period, resulting in no dispersion of Cr into the environment through leaf drop.  相似文献   
102.
ABSTRACT

Thirty-five actinobacterial isolates, obtained from button mushroom (Agaricus bisporus) substrates (i.e., compost in different phases of composting, black peat or casing layer) in Serbia in 2014–2016 were tested in vitro against the causal agents of green mold in cultivated mushroom. Out of six most promising isolates, A06 induced 42.4% in vitro growth inhibition of Trichoderma harzianum T54, and 27.6% inhibition of T. aggressivum f. europaeum T77. The novel strain A06 was identified as Streptomyces flavovirens based on macroscopic and cultural characteristics and 16S rDNA sequence and used in mushroom growing room experiments. Actinobacteria had no negative influence on mycelial growth of the cultivated mushroom in compost in situ. Isolate S. flavovirens A06 enhanced mushroom yield significantly, up to 31.5%. The A06 isolate was more efficient in enhancing yield after inoculation with the compost mold T. aggressivum (26.1%), compared to casing mold T. harzianum (8%). Considering disease incidence, actinobacteria significantly prevented green mold in compost caused by T. aggressivum (6.8%). However, fungicide prochloraz-Mn had a more significant role in reducing symptoms of casing mold, T. harzianum, in comparison with actinobacteria (24.2 and 11.8%, respectively). No significant differences between efficacies of S. flavovirens A06 and the fungicide prochloraz-Mn against T. aggressivum were revealed. These results imply that S. flavovirens A06 can be used to increase mushroom yield and contribute to disease control against the aggressive compost green mold disease caused by Trichoderma aggressivum.  相似文献   
103.
Bioaccumulation of cadmium, chromium, copper, manganese, nickel, lead and zinc in small terrestrial rodents – voles and their cestode parasite Paranoplocephala dentata was studied. Contents of Pb, Mn, Ni and Zn in the parasite were found to be higher than in the kidney and liver of the parasitized animals. Lead level in the cestode was 37 fold higher than in the liver of the infected rodents. Bioaccumulation factors of zinc, nickel and manganese in the cestode are mostly in the range from 2 to 4.5. Considering the different contents of manganese and zinc in livers of non-parasitized and parasitized rodents, kidney tissue was found to be more reliable than liver as an indicator of environmental pollution by manganese and zinc; the kidneys of parasitized animals showed no significant change in the concentrations of those elements that are accumulated in the cestode.  相似文献   
104.
Indicators were devised to classify air pollution monitoring sites according to the type of expected photochemical pollution. The indicators are based on measured ozone volume fractions, the most frequently monitored component of photochemical pollution, and in particular on two contributions: one due to the ratio of daily maximum-to-minimum ozone volume fractions and the other to observed peak values. The two contributions regarded as independent are logically connected by “and” and therefore mathematically combined by multiplication. The criterion of classification is mainly described by the mentioned ratio and incidences of ozone volume fractions exceeding the limit of 80 ppb. Twelve monitoring stations within the European network (Cooperative programme for monitoring and evaluation of long-range transmission of air pollutants in Europe, EMEP) were classified according to this indicator predicting what ozone levels can be expected at the particular sites during the growth season (April through September) into three groups: clean, medium, and polluted, based on the data for the 7 years (1997 to 2003).  相似文献   
105.
Aims. The aim of this study was to examine self-perceived compassion fatigue and compassion satisfaction among family physicians in Bosnia and Herzegovina and describe potential contributing factors. Methods. The cross-sectional study enrolled 120 family physicians. Professional quality of life compassion satisfaction and fatigue version 5 (ProQOL5) was used to assess compassion satisfaction and two components of compassion fatigue, secondary traumatic stress and burnout. The symptoms of chronic fatigue were evaluated using the Chalder fatigue scale. Results. The majority of family physicians had moderate levels of compassion satisfaction (70%), burnout (75%) and secondary traumatic stress (55.8%). Family physicians with higher levels of secondary traumatic stress reported chronic fatigue (p?=?0.001), longer length of service (p?=?0.024) and residency training (p?=?0.041). Chronic fatigue (p?=?0.001), living in a rural environment (p?=?0.033), larger size of practice (p?=?0.006) and high number of patients with chronic disease (p?=?0.001) were associated with a higher risk of burnout. Conclusion. Family physicians with large practices, long years of experience, a high number of chronically ill patients and experiencing chronic fatigue are at risk of developing compassion fatigue. A systematic exploration of compassion fatigue in relation to working conditions might provide an appropriate starting point for the development of preventive interventions.  相似文献   
106.
If there are no clearly defined management procedures, medical waste may represent a source of serious health hazards. Medical waste management was evaluated at the three hospitals in the Nisava and Toplica district, in Serbia. All the stages of existing waste management (segregation, collection, storage, transportation and disposal of waste) were examined by interviewing the personnel involved in the management of waste. The generated waste was a mixture of hazardous and non-hazardous waste. The study found that waste management performance in this district was poor and that there were problems in every stage of management. The results indicate that the waste generation rate was 1.92 kg bed(-1) day(-1) and consisted of 98.7% general waste and 1.3% sharps. Inappropriate segregation practices were the biggest problem and led to increased quantities of general waste. There were no specific regulations for the segregation of the medical waste. None of the surveyed hospitals have a system to refine wastewater and there were no training courses about hospital waste management.  相似文献   
107.
Not much has been written about air cleaning from ozone. The aim of this paper was to demonstrate the possibility of adsorption air cleaning from ozone. The second aim was to investigate the dependence of the efficiency of ozone removal from the air on the height of the adsorber layer and on concentrations of ozone, and to obtain empirical formulas for calculating the efficiency of ozone treatment. Equipment for air cleaning from ozone and nitrogen and sulphur dioxides is suggested.  相似文献   
108.
Pollen data have been recorded at Novi Sad in Serbia since 2000. The adopted method of producing pollen counts has been the use of five longitudinal transects that examine 19.64% of total sample surface. However, counting five transects is time consuming and so the main objective of this study is to investigate whether reducing the number to three or even two transects would have a significant effect on daily average and bi-hourly pollen concentrations, as well as the main characteristics of the pollen season and long-term trends. This study has shown that there is a loss of accuracy in daily average and bi-hourly pollen concentrations (an increase in % ERROR) as the sub-sampling area is reduced from five to three or two longitudinal transects. However, this loss of accuracy does not impact on the main characteristics of the season or long-term trends. As a result, this study can be used to justify changing the sub-sampling method used at Novi Sad from five to three longitudinal transects. The use of two longitudinal transects has been ruled out because, although quicker, the counts produced: (a) had the greatest amount of % ERROR, (b) altered the amount of influence of the independent variable on the dependent variable (the slope in regression analysis) and (c) the total sampled surface (7.86%) was less than the minimum requirement recommended by the European Aerobiology Society working group on Quality Control (at least 10% of total slide area).  相似文献   
109.
The interdependence of social and ecological processes is broadly acknowledged in the pursuit to enhance human wellbeing and prosperity for all. Yet, development interventions continue to prioritise economic development and short-term goals with little consideration of social-ecological interdependencies, ultimately undermining resilience and therefore efforts to deliver development outcomes. We propose and advance a coevolutionary perspective for rethinking development and its relationship to resilience. The perspective rests on three propositions: (1) social-ecological relationships coevolve through processes of variation, selection and retention, which are manifest in practices; (2) resilience is the capacity to filter practices (i.e. to influence what is selected and retained); and (3) development is a coevolutionary process shaping pathways of persistence, adaptation or transformation. Development interventions affect and are affected by social–ecological relationships and their coevolutionary dynamics, with consequences for resilience, often with perverse outcomes. A coevolutionary approach enables development interventions to better consider social–ecological interdependencies and dynamics. Adopting a coevolutionary perspective, which we illustrate with a case on agricultural biodiversity, encourages a radical rethinking of how resilience and development are conceptualised and practiced across global to local scales.  相似文献   
110.
Environmental Science and Pollution Research - The effect of soil amendments, i.e., compost, zeolite, and calcium oxide, on the chemical properties of soil contaminated with Cr(III) and Cr(VI) and...  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