全文获取类型
收费全文 | 44010篇 |
免费 | 5863篇 |
国内免费 | 3254篇 |
专业分类
化学 | 26384篇 |
晶体学 | 557篇 |
力学 | 2698篇 |
综合类 | 139篇 |
数学 | 4363篇 |
物理学 | 18986篇 |
出版年
2024年 | 48篇 |
2023年 | 720篇 |
2022年 | 879篇 |
2021年 | 1174篇 |
2020年 | 1451篇 |
2019年 | 1440篇 |
2018年 | 1317篇 |
2017年 | 1148篇 |
2016年 | 1809篇 |
2015年 | 1621篇 |
2014年 | 2174篇 |
2013年 | 2947篇 |
2012年 | 3605篇 |
2011年 | 3911篇 |
2010年 | 2609篇 |
2009年 | 2515篇 |
2008年 | 2822篇 |
2007年 | 2585篇 |
2006年 | 2497篇 |
2005年 | 1940篇 |
2004年 | 1576篇 |
2003年 | 1232篇 |
2002年 | 1146篇 |
2001年 | 1405篇 |
2000年 | 1009篇 |
1999年 | 1033篇 |
1998年 | 800篇 |
1997年 | 794篇 |
1996年 | 721篇 |
1995年 | 625篇 |
1994年 | 537篇 |
1993年 | 427篇 |
1992年 | 442篇 |
1991年 | 373篇 |
1990年 | 337篇 |
1989年 | 261篇 |
1988年 | 184篇 |
1987年 | 165篇 |
1986年 | 172篇 |
1985年 | 150篇 |
1984年 | 94篇 |
1983年 | 80篇 |
1982年 | 54篇 |
1981年 | 50篇 |
1980年 | 23篇 |
1977年 | 18篇 |
1976年 | 27篇 |
1975年 | 28篇 |
1974年 | 20篇 |
1973年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
Geometriae Dedicata - Inspired by a recent work of Grove and Petersen (Alexandrov spaces with maximal radius, 2018), where the authors studied positively curved Alexandrov spaces with largest... 相似文献
2.
International Journal of Theoretical Physics - We consider the stationary state of a spin-orbit coupled (SOC) binary Bose-Einstein condensates with dipole-dipole interaction (DDI). Our results are... 相似文献
3.
Nonlinear Dynamics - The hybrid neural model provides a computationally effective and biophysics-based neuron behavior model, which maintains its simplicity by incorporating the dynamics... 相似文献
4.
In this paper, we study the integrals of the Ricci curvature over metric balls in a Finsler manifold,which can be viewed as an L~q-norm of the Ricci curvature. By bounding such integrals from above, we obtain several Myers type theorems. 相似文献
5.
Designs, Codes and Cryptography - According to a magnific method due to I. Tamo and A. Barg, a class of polynomials over finite fields, called good polynomials, was introduced and used to construct... 相似文献
6.
Jiang Xin Zhao Dongxiao Chen Jialiang Li Wenting Li Kexin Chen Chao 《Kinetics and Catalysis》2022,63(5):470-479
Kinetics and Catalysis - A ternary synergistic photocatalyst H3PW12O40/Pt/UiO-66-NH2 was successfully fabricated for the first time through a simple solvothermal synthetic strategy. We found that... 相似文献
7.
8.
BIT Numerical Mathematics - In this paper, we introduce a novel class of embedded exponential-type low-regularity integrators (ELRIs) for solving the KdV equation and establish their optimal... 相似文献
9.
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
10.
Nonlinear Dynamics - This paper investigates the guaranteed cost positive consensus for linear multi-agent systems (MASs) with multiple time-varying delays and switching topologies. First,... 相似文献