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   391276篇
  免费   4221篇
  国内免费   1355篇
化学   206708篇
晶体学   4651篇
力学   17495篇
综合类   5篇
数学   41985篇
物理学   126008篇
  2018年   3847篇
  2017年   3723篇
  2016年   5904篇
  2015年   3883篇
  2014年   6087篇
  2013年   16928篇
  2012年   11966篇
  2011年   14884篇
  2010年   10400篇
  2009年   10311篇
  2008年   13659篇
  2007年   13783篇
  2006年   13100篇
  2005年   11862篇
  2004年   10983篇
  2003年   9807篇
  2002年   9054篇
  2001年   11345篇
  2000年   8505篇
  1999年   6538篇
  1998年   5281篇
  1997年   5381篇
  1996年   5118篇
  1995年   4937篇
  1994年   4831篇
  1993年   4775篇
  1992年   5353篇
  1991年   5329篇
  1990年   5108篇
  1989年   5100篇
  1988年   5058篇
  1987年   4984篇
  1986年   4683篇
  1985年   6415篇
  1984年   6638篇
  1983年   5366篇
  1982年   5657篇
  1981年   5597篇
  1980年   5401篇
  1979年   5680篇
  1978年   6042篇
  1977年   5791篇
  1976年   5840篇
  1975年   5416篇
  1974年   5421篇
  1973年   5458篇
  1972年   3719篇
  1971年   3105篇
  1968年   3328篇
  1967年   3342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.
Journal of Thermal Analysis and Calorimetry - The paper focuses on the analytical analysis of the propagation of a normal shock wave in an adiabatic gas flow with nanoparticles. A modified...  相似文献   
3.
Annals of Operations Research - In recent years, operations research in agriculture has improved the harvested yield, reduced the cost and time required for field operations, and maintained...  相似文献   
4.
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   
5.
Journal of Applied Spectroscopy - Three simple, sensitive, precise, and rapid spectrophotometric methods are developed and optimized for the assay of vardenafil in pharmaceutical formulations. The...  相似文献   
6.
Statistical Inference for Stochastic Processes - The class of autoregressive (AR) processes is extensively used to model temporal dependence in observed time series. Such models are easily...  相似文献   
7.
Balygin  K. A.  Kulik  S. P.  Molotkov  S. N. 《JETP Letters》2022,116(2):128-132
JETP Letters - A simple fundamental modification of quantum key distribution protocols has been proposed: it is not required to protect the results of avalanche detectors from an eavesdropper, but...  相似文献   
8.
Crystallography Reports - A surface structural analysis of two ceramic samples of zirconium oxide (ZrO2) sintered at 1550°C, stabilized in the tetragonal form, before and after hydrothermal...  相似文献   
9.
Russian Journal of Applied Chemistry - A method for the disposal of hydrolysis lignin waste based on its modification with ZnCl2 and FeCl3 and subsequent carbonization at 800°C was proposed....  相似文献   
10.
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   
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