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   180篇
  免费   1篇
  国内免费   13篇
安全科学   10篇
废物处理   23篇
环保管理   18篇
综合类   18篇
基础理论   35篇
污染及防治   48篇
评价与监测   29篇
社会与环境   12篇
灾害及防治   1篇
  2023年   3篇
  2022年   21篇
  2021年   15篇
  2020年   6篇
  2019年   9篇
  2018年   15篇
  2017年   9篇
  2016年   9篇
  2015年   7篇
  2014年   5篇
  2013年   26篇
  2012年   16篇
  2011年   12篇
  2010年   8篇
  2009年   4篇
  2008年   3篇
  2007年   5篇
  2005年   5篇
  2003年   2篇
  2000年   1篇
  1999年   1篇
  1997年   3篇
  1996年   1篇
  1994年   1篇
  1993年   1篇
  1991年   1篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1984年   1篇
  1965年   1篇
排序方式: 共有194条查询结果,搜索用时 827 毫秒
51.
The river Ravi, while passing through Lahore, the second largest city of Pakistan, gets highly polluted owning heavy loads of untreated municipal sewage and industrial effluents of diverse kinds. The fish, Catla catla sampled in two different seasons from three downstream polluted sites were compared with the samples of the same fish from an upstream, a less polluted site, for their physico-chemical parameters. The data were statistically analysed to study the effect of sites, seasons and their interaction on the physico-chemical parameters of waters and mineral uptake in fish muscles. Significant differences (P?<?0.001) among the sampling sites and seasons were observed. The river appeared to be polluted as indicated by the high values of total suspended solids (909 mg/l) and sulphate (964 mg/l) in comparison to the respective values of 150 and 600 mg/l being suggested as the safer values of drinking water of the National Environmental Quality Standards. Most trace and macro elements in fish muscles were increased with the increasing pollution loads from the upstream to the downstream sites of this river. The remarkable increases in the levels of all the investigated minerals in fish muscles from the polluted sites raise concerns about the long-term health of the river Ravi ecosystem and consequently the fish and its consumer’s health. The results contradict the opinion of the local population that the riverine fish are natural, more health-promoting and precious than the pond fish. Therefore, we strongly argue for the utilization of an effect-based monitoring approach to alleviate the detrimental effects of anthropogenic activities on fish and the fish consumers’ health.  相似文献   
52.
53.
ABSTRACT: Due to the spread of Islam in the seventh century the number of pilgrims to the City of Makkah increased sharply, resulting in an acute water shortage. To solve this problem, galleries were built to collect water from the upstream of Wadi Naaman and transfer it to Makkah. Expansion of Makkah and the absence of any mapping of the galleries have resulted in the destruction of a part of the galleries. This caused a discontinuity of flow in the galleries and, consequently, the ground water table is rising at a rate of 0.48 m/yr, causing environmental problems. Research was conducted to rehabilitate the destructed part of the galleries, and to find an appropriate use for the ground water. The study found that the quality of the ground water is suitable for landscaping purposes, that is, for the irrigation of trees and ornamental plants.  相似文献   
54.
The leaves of Robinia pseudo-acacia L. (Fabaceae) were evaluated as a biomonitors of heavy metal contamination in Denizli city, Turkey. Concentrations of Fe, Zn, Pb, Cu, Mn and Cd were determined in washed and unwashed leaves and soils collected from a wide range of sites with different degrees of metal pollution (industry, urban roadside, suburban) and from a rural (control) site by atomic absorption spectrometry. All the elements that measured were found to be at high levels in samples collected at industrial sites, except for lead and copper which were found at high levels in samples collected from urban roadsides that associated with the road traffic. The strong correlation between the degree of contamination and concentrations in all plant leaves assessed display that the leaves of R. pseudo-acacia reflect the environmental changes accurately, and that they seem as an effective biomonitor of environmental quality in areas subjected to industrial and traffic pollutions.  相似文献   
55.
In assessing and deciding the prediction schemes of solar irradiation countrywide, better the accuracy means better the management of energy transition toward renewables. Consequently, the present study is on the development of new models to make the most accurate possible estimations of the global and diffuse solar irradiation based on ground measurements. Such analysis produces the most accurate estimations for the input of solar energy systems. This is utmost significant for deciding the investments on solar energy systems and their design periods. Turkey is a high-potent country whose solar energy market has been growing rapidly. She doesn’t have adequate reliable measurement network and there is no estimation methodology developed for each and every point within its territory. Moreover, installing such a measurement system network doesn’t seem to be economically feasible and technically possible, inter alia. Accordingly, this study defines a methodology to make the most accurate estimations of monthly mean daily solar irradiation on horizontal surface and its diffuse and beam components. For the global and diffuse estimations, new methodologies in linear and quadratic forms are developed, compared, and discussed. The comparison is applied by using mean bias error and root mean square error statistical comparison methods. The measured data values used for modeling and comparisons are provided from the State Meteorological Service of Turkey responsible authority for solar irradiation measurements. The results revealed that the methodologies explained in this study give very high accurate values of total solar irradiation on a horizontal surface and its diffuse component.  相似文献   
56.
57.
58.
Increasing urbanization and changes in land use in Langat river basin lead to adverse impacts on the environment compartment. One of the major challenges is in identifying sources of organic contaminants. This study presented the application of selected chemometric techniques: cluster analysis (CA), discriminant analysis (DA), and principal component analysis (PCA) to classify the pollution sources in Langat river basin based on the analysis of water and sediment samples collected from 24 stations, monitored for 14 organic contaminants from polycyclic aromatic hydrocarbons (PAHs), sterols, and pesticides groups. The CA and DA enabled to group 24 monitoring sites into three groups of pollution source (industry and urban socioeconomic, agricultural activity, and urban/domestic sewage) with five major discriminating variables: naphthalene, pyrene, benzo[a]pyrene, coprostanol, and cholesterol. PCA analysis, applied to water data sets, resulted in four latent factors explaining 79.0% of the total variance while sediment samples gave five latent factors with 77.6% explained variance. The varifactors (VFs) obtained from PCA indicated that sterols (coprostanol, cholesterol, stigmasterol, β-sitosterol, and stigmastanol) are strongly correlated to domestic and urban sewage, PAHs (naphthalene, acenaphthene, pyrene, benzo[a]anthracene, and benzo[a]pyrene) from industrial and urban activities and chlorpyrifos correlated to samples nearby agricultural sites. The results demonstrated that chemometric techniques can be used for rapid assessment of water and sediment contaminations.  相似文献   
59.
Environmental Science and Pollution Research - The World Health Organization (WHO) recognized a novel coronavirus as the causative agent of a new form of pneumonia. It was subsequently named...  相似文献   
60.
Floating roof storage tank boilover   总被引:1,自引:0,他引:1  
Storage tanks are important facilities for the major hazard installations (MHIs) to store large quantity of crude oil. There is several fire types can occur with large diameter open top floating roof storage tanks. Boilover is considered one of the most dangerous fires in large-scale oil tank. The world has witnessed many incidents due to boilover in floating roof storage tank. Boilover problem has been studied in experiments and by models to understand how to control the boilover phenomena. An experimental study has been carried out in Jebel Dhanna (JD) terminal area by Abu Dhabi Company for Onshore Oil Operations (ADCO) with support of Resource Protection International (RPI) consultant. 2.4 m diameter and 4.5 m diameters pans have been used to study the characteristics of the large oil-tank fires (i) to gain more knowledge of the boilover phenomenon of crude oil (ii) verify if the crude oil stored by ADCO would boilover (ii) estimation of rate of hot-zone growth and the period needed from ignition to boilover (iii) estimation of radiant heat and consequences of boilover. This paper presents an overview on the floating roof storage tank boilover. The paper also presents briefly boilover experimental research study carried out by ADCO.  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