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   6197篇
  免费   56篇
  国内免费   25篇
安全科学   88篇
废物处理   391篇
环保管理   422篇
综合类   888篇
基础理论   1322篇
环境理论   9篇
污染及防治   2190篇
评价与监测   561篇
社会与环境   392篇
灾害及防治   15篇
  2023年   71篇
  2022年   178篇
  2021年   220篇
  2020年   84篇
  2019年   82篇
  2018年   218篇
  2017年   198篇
  2016年   318篇
  2015年   175篇
  2014年   363篇
  2013年   596篇
  2012年   396篇
  2011年   388篇
  2010年   302篇
  2009年   222篇
  2008年   363篇
  2007年   382篇
  2006年   304篇
  2005年   224篇
  2004年   179篇
  2003年   159篇
  2002年   146篇
  2001年   85篇
  2000年   67篇
  1999年   52篇
  1998年   25篇
  1997年   19篇
  1996年   17篇
  1995年   34篇
  1994年   24篇
  1993年   15篇
  1992年   11篇
  1991年   10篇
  1990年   14篇
  1989年   9篇
  1985年   7篇
  1967年   9篇
  1966年   13篇
  1965年   16篇
  1964年   31篇
  1963年   12篇
  1962年   17篇
  1961年   11篇
  1960年   9篇
  1959年   27篇
  1958年   37篇
  1957年   20篇
  1956年   14篇
  1955年   19篇
  1954年   7篇
排序方式: 共有6278条查询结果,搜索用时 15 毫秒
131.
Environmental Science and Pollution Research - It is well known that road transport emits various trace elements into the environment, which are deposited in soils in the vicinity of roads,...  相似文献   
132.
Environmental Science and Pollution Research - A linear algebra theorem like Cramer’s rule was used for the analysis of a system of equations obtained from UV spectroscopy, and results were...  相似文献   
133.
Environmental Science and Pollution Research - Glyphosate is the most used herbicide worldwide. Many studies have reported glyphosate risks to aquatic organisms of different trophic levels....  相似文献   
134.

The presence of potentially hazardous elements (PHEs) in playground soils is generally associated with anthropogenic sources such as vehicle traffic, industries, construction sites, and biomass burning. Studies indicate that PHEs are harmful to human health and may even be carcinogenic. Therefore, the aim of this study was to evaluate the physicochemical, morphological, and mineralogical properties of soil samples from three public playgrounds located in the cities of Bogota, Medellin, and Barranquilla. Besides, the possible impacts caused by the aerodynamics of particles in Colombian cities were verified. The morphology, composition, and structure of the nanoparticles (NPs) (< 100 nm) present in these soils were evaluated by field emission scanning electron microscopy (FE-SEM) equipped with high-precision field emission (FE) and high-resolution transmission electron microscopy (HR-TEM). Soil samples were predominantly feldspar, quartz, and, to a lesser extent, clay minerals, carbonates, and hematites. The average content of PHEs was anthropogenically enriched in relation to the upper continental crust. As and Sn showed a large spatial variation, indicating the influence of local sources, such as vehicle traffic and industries. There is an inverse relationship between the total concentrations of some elements and their leachable fractions. The accumulation of traffic-derived PHEs has a negative impact on human health and the environment, which is alarming, especially for elements such as Pb, Sb, or As. Therefore, the presence of PHEs should receive greater attention from public health professionals, and limits should be set and exposures controlled. This study includes the construction of a baseline that provides basic information on pollution, its sources, and exposure routes for humans in the vicinity of Colombia’s major cities, characterized by their increasing urbanization and industrialization.

  相似文献   
135.

Natural products may be applied in a wide range of domains, from agriculture to food and pharmaceutical industries. In this study, the antioxidant properties and the capacity to inhibit some enzymatic activities of Euphorbia resinifera and Euphorbia officinarum aqueous extracts and honeys were assessed. The physicochemical characteristics were also evaluated. Higher amounts of iron, copper and aluminium were detected in E. officinarum honey, which may indicate environmental pollution around the beehives or inadequate storage of honey samples. This honey sample showed higher amounts of total phenols and better capacity for scavenging superoxide anion free radicals and DPPH free radicals as compared with E. resinifera honey, but poorer capacity for inhibiting lipoxygenase, acetylcholinesterase, tyrosinase and xanthine oxidase. The ratio plant mass:solvent volume (1:100) and extraction time (1 - 2 h) were associated with higher total phenols and better antioxidant activities and lipoxygenase, acetylcholinesterase and tyrosinase inhibitory activities, regardless of the plant species. The aqueous extracts had systematically higher in vitro activities than the respective honey samples.

  相似文献   
136.
Environmental Science and Pollution Research - A theoretical physicochemical and thermodynamic investigation of the adsorption of heavy metals Zn2+, Cd2+, Ni2+, and Cu2+on carbon-based adsorbents...  相似文献   
137.
Environmental Science and Pollution Research - A complete survey is presented on the inorganic composition of the euhalophyte annual succulent species Salicornia patula (Chenopodiaceae), including...  相似文献   
138.
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   
139.
Environmental Science and Pollution Research - This work studies the effects of different bromide-based ionic liquids, with phosphonium and ammonium cations, towards several environmental...  相似文献   
140.
Norovirus (NoV) is recognized as the most common cause of foodborne outbreaks. In 2014, an outbreak of acute gastroenteritis occurred on a cruise ship in Brazil, and NoV became the suspected etiology. Here we present the molecular identification of the NoV strains and the use of sequence analysis to determine modes of virus transmission. Food (cream cheese, tuna salad, grilled fish, orange mousse, and vegetables soup) and clinical samples were analyzed by ELISA, conventional RT-PCR, qRT-PCR, and sequencing. Genogroup GII NoV was identified by ELISA and conventional RT-PCR in fecal samples from 5 of 12 patients tested (41.7%), and in the orange mousse food sample by conventional RT-PCR and qRT-PCR. Two fecal GII NoV samples and the orange mousse GII NoV sample were successfully genotyped as GII.Pe (ORF 1), revealed 98.0–98.8% identities among them, and shared phylogenetically distinct cluster. Establishing the source of a NoV outbreak can be a challenging task. In this report, the molecular analysis of the partial RdRp NoV gene provided a powerful tool for genotyping (GII.Pe) and tracking of outbreak-related samples. In addition, the same fast and simple extraction methods applied to clinical samples could be successfully used for complex food matrices, and have the potential to be introduced in routine laboratories for screening foods for presence of NoV.  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