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   253篇
  免费   1篇
  国内免费   12篇
安全科学   7篇
废物处理   26篇
环保管理   19篇
综合类   20篇
基础理论   31篇
污染及防治   131篇
评价与监测   20篇
社会与环境   10篇
灾害及防治   2篇
  2023年   4篇
  2022年   44篇
  2021年   33篇
  2020年   9篇
  2019年   17篇
  2018年   14篇
  2017年   17篇
  2016年   10篇
  2015年   8篇
  2014年   17篇
  2013年   17篇
  2012年   10篇
  2011年   10篇
  2010年   6篇
  2009年   5篇
  2008年   13篇
  2007年   5篇
  2006年   9篇
  2005年   1篇
  2004年   2篇
  2003年   2篇
  2002年   5篇
  2001年   1篇
  2000年   2篇
  1996年   2篇
  1995年   1篇
  1992年   1篇
  1991年   1篇
排序方式: 共有266条查询结果,搜索用时 15 毫秒
101.
Environmental Science and Pollution Research - Methanol intoxication is a global problem with serious morbidities and mortalities. Apart from the lifelong disabilities experienced by methanol...  相似文献   
102.
Removal efficiencies, kinetics and degradation pathways of aldrin, endosulfan α and endosulfan β in vegetable waste were evaluated during rotary drum and conventional windrow composting. The highest percentage removal of aldrin, endosulfan α and endosulfan β in rotary drum composting was 86.8, 83.3 and 85.3% respectively, whereas in windrow composting, it was 66.6%, 77.7% and 67.2% respectively. The rate constant of degradation of aldrin, endosulfan α and endosulfan β during rotary drum composting ranged from 0.410–0.778, 0.057–0.076 and 0.009–0.061 day?1 respectively. The pathways of degradation of these pesticides in composting process were proposed. Metabolites dieldrin and 1 hydroxychlorodene formed during composting of aldrin in the vegetable waste indicated the occurrence of epoxidation reaction and oxidation of bridge carbon of aldrin containing the methylene group. Formation of chloroendic acid and chloroendic anhydride during composting of endosulfan containing vegetable waste support the occurrence of endosulfan sulfate and dehydration reaction respectively.  相似文献   
103.
Lahore, Pakistan is an emerging megacity that is heavily polluted with high levels of particle air pollution. In this study, respirable particulate matter (PM2.5 and PM10) were collected every sixth day in Lahore from 12 January 2007 to 19 January 2008. Ambient aerosol was characterized using well-established chemical methods for mass, organic carbon (OC), elemental carbon (EC), ionic species (sulfate, nitrate, chloride, ammonium, sodium, calcium, and potassium), and organic species. The annual average concentration (±one standard deviation) of PM2.5 was 194 ± 94 μg m?3 and PM10 was 336 ± 135 μg m?3. Coarse aerosol (PM10?2.5) was dominated by crustal sources like dust (74 ± 16%, annual average ± one standard deviation), whereas fine particles were dominated by carbonaceous aerosol (organic matter and elemental carbon, 61 ± 17%). Organic tracer species were used to identify sources of PM2.5 OC and chemical mass balance (CMB) modeling was used to estimate relative source contributions. On an annual basis, non-catalyzed motor vehicles accounted for more than half of primary OC (53 ± 19%). Lesser sources included biomass burning (10 ± 5%) and the combined source of diesel engines and residual fuel oil combustion (6 ± 2%). Secondary organic aerosol (SOA) was an important contributor to ambient OC, particularly during the winter when secondary processing of aerosol species during fog episodes was expected. Coal combustion alone contributed a small percentage of organic aerosol (1.9 ± 0.3%), but showed strong linear correlation with unidentified sources of OC that contributed more significantly (27 ± 16%). Brick kilns, where coal and other low quality fuels are burned together, are suggested as the most probable origins of unapportioned OC. The chemical profiling of emissions from brick kilns and other sources unique to Lahore would contribute to a better understanding of OC sources in this megacity.  相似文献   
104.
Biosorption potential of new low cost biosorbent prepared from vegetable waste, composed of 1:1 mixture of potato and carrot peels for the removal of Ni(II) from aqueous solution was determined. The residual metallic ion concentrations were determined using an atomic absorption spectrophotometric technique (AAS). Batch experiments were conducted to optimize parameters such as initial pH, temperature, contact time, initial metal ion concentration and biosorbent dose and the results showed that maximum adsorption of Nickel (79.32 %) occurs when the contents were stirred for 75 min with 3.0 g of biosorbent at 35 °C and pH 4. Kinetic studies of the reaction revealed that it follows a pseudo-second order reaction. The experimental results were analyzed in terms of Langmuir and Freundlich isotherms. The Langmuir isotherm model fits well to data of Ni(II) biosorption by the prepared biomass as compared to the model of Freundlich. Both neat and Ni loaded biosorbent samples were analyzed by AAS using a dry ashing process in a furnace and also by use of a FT-IR spectrophotometer and an X-Ray florescence spectrometer in order to confirm the biosorption of Ni(II) and the results have revealed that a significant amount of Ni is present in the spent biosorbent.  相似文献   
105.

Sources of renewable energy have received wide attention in the literature because of serious threats to the environment. However, some renewable resources, including biomass energy role is debatable in the energy economics literature. This empirical work focuses to analyze the role of biomass energy in carbon dioxide (CO2) emissions using the framework of the environmental Kuznets curve (EKC) in Pakistan over the period from 1980 to 2015. The bound testing approach suggests there is cointegration among study variables. The study uses an auto-regressive distributed lag model (ARDL) with a structural break in the series. To summarize the findings of the study, it can be inferred that biomass energy increase CO2 emissions. In addition, biomass energy helps to form a U-shaped relationship between income and CO2 emissions that support the EKC hypothesis. Also, the feedback hypothesis is found between biomass energy and CO2 emissions. The findings would guide policymaker with practical guidelines to formulate policies to utilize a high amount of biomass energy in a sustainable manner.

  相似文献   
106.
Economic potential of recycling business in Lahore, Pakistan   总被引:1,自引:0,他引:1  
The state of household waste recycling in Lahore city, Pakistan with a population of 7.2 million was analyzed. Data on solid waste recycling were gathered from residents of low-, middle- and high-income groups, as well as from scavengers and junkshops. The recycling activities in Lahore exert a significant impact on resource conservation, creation of jobs, provision of economic opportunity and reduction in the magnitude of waste disposal problems. A cost analysis is presented to show the income that can be generated through a well-planned recycling program. It is shown that 21.2% of all recyclable waste in Lahore is recycled, and it generates an amount of Rs. 271 million (US dollars 4.5 million) per year through the informal sector. However, if the recycling practice is owned by the formal sector, it can save an amount of Rs. 65 million by reducing the collection cost. If recycling is adopted as an industry, it can generate revenues of Rs. 530 million (US dollars 8.8 million) per year and can also save enormous amount of energy, as well as the natural resources.  相似文献   
107.
The leaves of date palms were evaluated as a possible biomonitor of heavy metal contamination in Ma’an city, Jordan. Concentrations of (Fe), (Pb), (Zn), (Cu), (Ni), and (Cr) were determined in washed and unwashed leaves and soil samples collected from different sites with different degrees of metal contamination (urban, suburban, industrial, highway and rural sites); separate leaves were taken from outside the city to be used as a control sample. Samples collected from industrial sites were found to have high concentrations of all metals except those of Cu, Ni and Pb, which were found at high levels in the highway site samples which is associated with the road traffic. The difference between unwashed and washed samples showed that metal pollutants exist as contaminants, particularly Pb, Zn and Ni, which varied in concentration, depending on the source of the metal.  相似文献   
108.
Dichlorodiphenyltrichloroethane (DDT) belongs to one of the most hazardous groups of chemicals called persistent organic pollutants. Many organochlorine pesticides including p,p(')-DDT are long lasting due to their non-degradability can travel to distant places and being fat soluble can accumulate in animals and human bodies. Due to the persistent nature of p,p(')-DDT, its adverse environmental and health impacts, the present study was undertaken to examine the residual p,p(')-DDT in and around abandoned p,p(')-DDT manufacturing factory in Amman Gharh, Nowshera, NWFP. Samples of soil, sediments and water were collected in and around the factory area, nearby p,p(')-DDT stores, main factory drain leading to river Kabul and nearby villages. Standard procedures were used for the collection, transportation and storage of samples for analyses. Extraction of each sample for p,p(')-DDT analyses was carried out in triplicates using Soxhelt extraction. p,p(')-DDT contents in the samples were analyzed by capillary GC with electron capture detector. Most of the samples collected up to half kilometer distance from the site of the DDT factory were found contaminated. Further the level of p,p(')-DDT decreased with increasing depth from top to bottom and with distance from the site. The results indicate that there is no immediate threat to underground water reservoirs.  相似文献   
109.
Environmental Geochemistry and Health - Arsenic (As) and lead (Pb) are highly toxic and carcinogenic metal(loid)s. The present study evaluated the human exposure risk via estimating As and Pb...  相似文献   
110.
Environmental Science and Pollution Research - India is predominantly a fossil fuel-intensive South Asian country that has traditionally settled for higher economic gains at the expense of lower...  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