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   307458篇
  免费   4249篇
  国内免费   1023篇
化学   166350篇
晶体学   3296篇
力学   12890篇
综合类   6篇
数学   35741篇
物理学   94447篇
  2020年   1994篇
  2019年   1954篇
  2018年   1975篇
  2017年   1870篇
  2016年   3852篇
  2015年   3229篇
  2014年   4430篇
  2013年   14010篇
  2012年   10818篇
  2011年   13590篇
  2010年   8278篇
  2009年   8084篇
  2008年   12307篇
  2007年   12494篇
  2006年   12273篇
  2005年   11209篇
  2004年   10009篇
  2003年   8769篇
  2002年   8038篇
  2001年   9698篇
  2000年   7145篇
  1999年   5526篇
  1998年   4292篇
  1997年   4304篇
  1996年   4284篇
  1995年   4227篇
  1994年   4004篇
  1993年   3833篇
  1992年   4301篇
  1991年   4186篇
  1990年   3876篇
  1989年   3718篇
  1988年   4024篇
  1987年   3676篇
  1986年   3596篇
  1985年   5245篇
  1984年   5323篇
  1983年   4297篇
  1982年   4675篇
  1981年   4728篇
  1980年   4466篇
  1979年   4612篇
  1978年   4614篇
  1977年   4590篇
  1976年   4560篇
  1975年   4451篇
  1974年   4320篇
  1973年   4487篇
  1972年   2533篇
  1971年   1842篇
排序方式: 共有10000条查询结果,搜索用时 15 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