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   222942篇
  免费   2836篇
  国内免费   727篇
化学   124272篇
晶体学   3467篇
力学   8724篇
综合类   14篇
数学   22643篇
物理学   67385篇
  2018年   1763篇
  2017年   1662篇
  2016年   3129篇
  2015年   2361篇
  2014年   3175篇
  2013年   9129篇
  2012年   6847篇
  2011年   8378篇
  2010年   5517篇
  2009年   5381篇
  2008年   7546篇
  2007年   7612篇
  2006年   7162篇
  2005年   7027篇
  2004年   6497篇
  2003年   5589篇
  2002年   5076篇
  2001年   6390篇
  2000年   4989篇
  1999年   3896篇
  1998年   3073篇
  1997年   3071篇
  1996年   3120篇
  1995年   2847篇
  1994年   2714篇
  1993年   2635篇
  1992年   3118篇
  1991年   2928篇
  1990年   2830篇
  1989年   2834篇
  1988年   2757篇
  1987年   2753篇
  1986年   2568篇
  1985年   3489篇
  1984年   3487篇
  1983年   2876篇
  1982年   3071篇
  1981年   2999篇
  1980年   2917篇
  1979年   3023篇
  1978年   3293篇
  1977年   3071篇
  1976年   3017篇
  1975年   2849篇
  1974年   2821篇
  1973年   2818篇
  1972年   1809篇
  1968年   1948篇
  1967年   2148篇
  1966年   1937篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
51.
52.
53.
54.
55.
Journal of Solid State Electrochemistry - In this work, the use of neodymium electrodes as a basis for the immobilization of magnetite nanoparticles has been carried out. The sensitivity and...  相似文献   
56.
Active anodes, especially those consisting of metal mixed oxides (MMOs) containing Ru and/or Ir oxides, have been applied in the treatment of wastewater, especially when chloride ions are present. Their characteristics continuously drive the study of applications of these materials, be they in the degradation of different organic molecules, the preparation of new electrode materials and in the association of various processes to increase pollutant removal. Thus, this brief review aims to present some of the recent advances in the application of active anode materials in environmental electrochemistry. Focussing on the 2018–2020 period, it is possible to note many applied studies, using commercially available materials, covering a wide range of target pollutants. Still other studies aim to modify the catalyst surfaces to increase the mineralization capacity, and the use of these anodes in the production of free chlorine species to mediate indirect organic reduction is observed.  相似文献   
57.
Annals of Operations Research - The vehicle routing problem is a traditional combinatorial problem with practical relevance for a wide range of industries. In the literature, several specificities...  相似文献   
58.
Exosomes are nanovesicles secreted by most cellular types that carry important biochemical compounds throughout the body with different purposes, playing a preponderant role in cellular communication. Because of their structure, physicochemical properties and stability, recent studies are focusing in their use as nanocarriers for different therapeutic compounds for the treatment of different diseases ranging from cancer to Parkinson's disease. However, current bioseparation protocols and methodologies are selected based on the final exosome application or intended use and present both advantages and disadvantages when compared among them. In this context, this review aims to present the most important technologies available for exosome isolation while discussing their advantages and disadvantages and the possibilities of being combined with other strategies. This is critical since the development of novel exosome‐based therapeutic strategies will be constrained to the effectiveness and yield of the selected downstream purification methodologies for which a thorough understanding of the available technological resources is needed.  相似文献   
59.
Journal of Solid State Electrochemistry - In this study, galvanostatic electrolysis, through the use of the platinum supported on Ti (Ti/Pt) and Ti/TiO2-nanotubes/PbO2 anodes, was conducted in an...  相似文献   
60.
Xu  H. J.  Zhang  Q. G.  Debenest  G. 《Transport in Porous Media》2021,140(3):625-627
Transport in Porous Media - The theme of coupling problems for adsorption, absorption and thermochemical transport in porous media is very important for engineering applications. Based on 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