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   4454篇
  免费   34篇
  国内免费   22篇
安全科学   54篇
废物处理   276篇
环保管理   278篇
综合类   756篇
基础理论   907篇
环境理论   5篇
污染及防治   1543篇
评价与监测   415篇
社会与环境   265篇
灾害及防治   11篇
  2023年   52篇
  2022年   134篇
  2021年   144篇
  2020年   57篇
  2019年   59篇
  2018年   169篇
  2017年   126篇
  2016年   224篇
  2015年   124篇
  2014年   254篇
  2013年   432篇
  2012年   276篇
  2011年   271篇
  2010年   202篇
  2009年   161篇
  2008年   247篇
  2007年   259篇
  2006年   238篇
  2005年   154篇
  2004年   131篇
  2003年   117篇
  2002年   94篇
  2001年   65篇
  2000年   46篇
  1999年   34篇
  1998年   15篇
  1997年   15篇
  1996年   8篇
  1995年   28篇
  1994年   18篇
  1993年   13篇
  1992年   8篇
  1990年   11篇
  1989年   10篇
  1975年   7篇
  1970年   7篇
  1967年   8篇
  1966年   11篇
  1965年   15篇
  1964年   28篇
  1963年   12篇
  1962年   18篇
  1961年   14篇
  1960年   9篇
  1959年   26篇
  1958年   26篇
  1957年   18篇
  1956年   14篇
  1955年   18篇
  1954年   9篇
排序方式: 共有4510条查询结果,搜索用时 9 毫秒
21.
Dynamic Games in the Economics and Management of Pollution   总被引:1,自引:0,他引:1  
The paper provides a survey of the literature which utilizes dynamic state-space games to formulate and analyze intertemporal, many decision-maker problems in the economics and management of pollution.  相似文献   
22.
A biomonitoring survey using the moss species Hypnum cupressiforme Hedw. was conducted in the surroundings of two steel plants located in the North of Spain. Levels of V, Cr, Ni, Cu, Zn, As, Cd, Hg, Pb and N were determined. Very high concentrations in the areas of study were detected when compared to nearby unaffected regions. Similar trends were observed for all the elements in the differently orientated transects, showing an appreciable influence of the NW prevailing winds of the region in the dispersion of pollutants, as well as a clear decreasing gradient in the concentrations of metals in mosses within a distance of 1500 meters from the facilities. A differentiation between the elements emitted by the chimney as result of the industrial activity (V, Cr, Ni, Cu and As) and those with a high presence in steel slag deposits (Zn, Cd, Hg and Pb) was observed. The range of contamination was also established by means of the Contamination Factor, indicating a category 4 out of 6 categories, which shows the high levels reported in the areas of study. A different dynamic was registered for nitrogen regarding the rest of the heavy metals analysed except for Hg, probably due to the elevated volatility and mobility of both elements, as well as their high persistence in the atmosphere.  相似文献   
23.
Indoor sources have been identified as a major contributor to the increase of particle concentration in indoor environments. The work presented here is a study of the characteristics of particulate matter number size distribution and mass concentration under controlled indoor activities in a laboratory room. The objective is to characterize particulate matter concentrations indoors resulted under the influence of specific sources. Measurements were performed in an empty laboratory (period September–October 2006) using a GRIMM SMPS+C system (particle size range between 11.1 and 1083.3 nm), a DustTrak Aerosol Monitor (TSI) and a P-Trak Ultrafine Particle Counter (TSI). The studied indoor activities included candle burning, hot plate heating, water boiling, onion frying, vacuuming, hair drying, hair spraying, smoking and burning of incense stick. The AMANpsd computer algorithm was used to evaluate the modal structure of measured particle number size distribution data. Furthermore, the change of the particle number size distribution shape under the influence of different emission sources was studied versus time. Finally the particle emission rates were computed. High particle number concentrations were observed during smoking, onion frying, candle burning and incense stick burning. The highest particle mass concentrations were measured during smoking and hair spraying. The shift of the particle size distribution to larger diameters suggests the presence of strong coagulation effect during candle burning, incense stick burning, smoking and onion frying. The size distribution was mainly bimodal during onion frying and candle burning, whereas the size distribution remained unimodal during incense stick burning and smoking experiments.  相似文献   
24.
The chemical speciation of the 16 polycyclic aromatic hydrocarbons associated to the particulate matter of conventional diesel fuel, rapeseed methyl esters, waste cooking oil methyl esters, waste cooking oil ethyl esters and their conventional fuel blends has been carried out. The speciation of these individual compounds was made by a combination of thermal extraction, solid phase micro-extraction and GC/MS analysis. This PAH speciation method was applied to a real samples obtained from a diesel engine under two different operating modes, urban and extraurban modes. The purpose of this work was to study the relationship between the amount, type and carcinogenic potency of polycyclic aromatic hydrocarbons in engine emissions and the multi-component biodiesel fuel composition.  相似文献   
25.
26.

Monitoring of body burden of toxic elements is usually based on analysis of concentration of particular elements in blood, urine and/or hair. Analysis of these matrices, however, predominantly reflects short- or medium-term exposure to trace elements or pollutants. In this work, urinary stones were investigated as a matrix for monitoring long-term exposure to toxic and essential elements. A total of 431 samples of urinary calculi were subjected to mineralogical and elemental analysis by infrared spectroscopy and inductively coupled plasma mass spectrometry. The effect of mineralogical composition of the stones and other parameters such as sex, age and geographical location on contents of trace and minor elements is presented. Our results demonstrate the applicability of such approach and confirm that the analysis of urinary calculi can be helpful in providing complementary information on human exposure to trace metals and their excretion. Analysis of whewellite stones (calcium oxalate monohydrate) with content of phosphorus <0.6 % has been proved to be a promising tool for biomonitoring of trace and minor elements.

  相似文献   
27.
Environmental Science and Pollution Research - The most common mycotoxin found in European foodstuffs, especially unprocessed grains, is deoxynivalenol (DON), which inhibits proteosynthesis and...  相似文献   
28.
Environmental Science and Pollution Research - Traditional medicine (TM) also known as folk medicine consists of medical knowledge systems that were developed over generations in various countries...  相似文献   
29.
Environmental Science and Pollution Research - This study reports how adding a membrane filter (0.45-μm cellulose nitrate filter) between a glass fibre filter and the solid phase extraction...  相似文献   
30.
Environmental Science and Pollution Research - Phytoremediation techniques have been proposed as ecological methods to clean up contaminated sites. This study is aimed to evaluate the effect of the...  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