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   462134篇
  免费   4665篇
  国内免费   1468篇
化学   215948篇
晶体学   5353篇
力学   24239篇
综合类   7篇
数学   84734篇
物理学   137986篇
  2020年   1999篇
  2019年   1974篇
  2018年   18854篇
  2017年   19463篇
  2016年   12486篇
  2015年   4817篇
  2014年   4824篇
  2013年   14414篇
  2012年   17672篇
  2011年   32963篇
  2010年   19552篇
  2009年   19805篇
  2008年   27357篇
  2007年   32351篇
  2006年   12613篇
  2005年   19213篇
  2004年   14754篇
  2003年   13544篇
  2002年   10093篇
  2001年   10015篇
  2000年   7623篇
  1999年   5691篇
  1998年   4501篇
  1997年   4433篇
  1996年   4568篇
  1995年   4425篇
  1994年   4148篇
  1993年   3986篇
  1992年   4429篇
  1991年   4314篇
  1990年   4000篇
  1989年   3853篇
  1988年   4160篇
  1987年   3806篇
  1986年   3708篇
  1985年   5378篇
  1984年   5470篇
  1983年   4421篇
  1982年   4805篇
  1981年   4857篇
  1980年   4603篇
  1979年   4741篇
  1978年   4751篇
  1977年   4648篇
  1976年   4642篇
  1975年   4536篇
  1974年   4375篇
  1973年   4594篇
  1972年   2576篇
  1971年   1872篇
排序方式: 共有10000条查询结果,搜索用时 125 毫秒
1.
Pomogaev  V. A.  Lee  H. J.  Goh  E.  Tchaikovskaya  O. N.  Kononov  A. I.  Avramov  P. V. 《Russian Physics Journal》2022,64(11):2076-2081
Russian Physics Journal - Theoretical calculations of excited states in the complexes of gold and silver three-atom nanoclusters with carbon quantum nanodots are performed using the M062X...  相似文献   
2.
Structural Chemistry - In the present work, the energy contribution of the sulfur atom in a heterocycle and in a disulfide bond in solid and gas phases was calculated. To achieve this goal,...  相似文献   
3.
The European Physical Journal A - The goal of the present paper is twofold. First, a novel expansion many-body method applicable to superfluid open-shell nuclei, the so-called Bogoliubov in-medium...  相似文献   
4.
Transport in Porous Media - Membrane filtration of feed containing multiple species of particles is a common process in the industrial setting. In this work, we propose a model for filtration of a...  相似文献   
5.
Carnicer  J. M.  Khiar  Y.  Peña  J. M. 《Numerical Algorithms》2022,90(4):1691-1713
Numerical Algorithms - An inverse central ordering of the nodes is proposed for the Newton interpolation formula. This ordering may improve the stability for certain distributions of nodes. For...  相似文献   
6.
Journal of Solid State Electrochemistry - Sodium-ion batteries have emerged as an exciting alternative to commercially dominant lithium-ion batteries for electric vehicles and other applications....  相似文献   
7.
Atopic dermatitis is characterized by leukocyte migration into the skin dermis and typically driven by excessive chemokine production at the site of inflammation. Conventional topical formulations such as gels, creams, and ointments are insufficient for this treatment because of low penetration of drug molecules into the targeted skin tissues. Herein, using a simple, green, sustainable strategy, we have developed novel primary zein nanoparticles embedded in curcumin (Cur) and coated with silk sericin (ZHSCs) for the topical delivery of Cur to penetrate into the dermis and exercise anti-dermatitis effects on the lesion with minimal side-effects. Transdermal delivery experiments and porcine skin fluorescence imaging indicated that ZHSCs facilitate the penetration of Cur across the epidermis layer of skin to reach deep-seated sites. Notably, ZHSCs = 1:0.25 (zein-to-silk sericin mass ratios of 1:0.25) markedly elevated the skin permeability and cumulative turnover of Cur transferred, which were provided a greater than a 3.8-fold increase relative to free Cur. The special nanoparticles of ZHS = 1:0.25 possessed the deepest localization depth and experience a transition of the particle structure and core-shell separation after penetrating into the dermis of skin. In a cell model of dermatitis induced by tumor necrosis factor α/interferon γ co-stimulation, compared with free Cur, Cur-loaded ZHS nanoparticles down-regulated the generation of inflammatory cytokines and chemokines in keratinocytes through suppression of the nuclear translocation of NF-κBp65 and hence exerted an anti-dermatitis effect. This strategy may provide new avenues and direction for the demanding issues of valid topical delivery systems.  相似文献   
8.
Saikia  D.  Parnami  Sugam  Borah  J. P. 《JETP Letters》2022,116(7):444-448
JETP Letters - The magnetic properties of Co-doped CdS has been investigated by ab initio calculations using the GGA + U approximation. The study reveals the ferromagnetic ordering of Co-doped CdS...  相似文献   
9.
Theoretical and Mathematical Physics - An Erratum to this paper has been published: https://doi.org/10.1134/S0040577922060034  相似文献   
10.
Applied Mathematics and Mechanics - Mechanical models of residually stressed fibre-reinforced solids, which do not resist bending, have been developed in the literature. However, in some residually...  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