全文获取类型
收费全文 | 218169篇 |
免费 | 4364篇 |
国内免费 | 752篇 |
专业分类
化学 | 122137篇 |
晶体学 | 2318篇 |
力学 | 9160篇 |
综合类 | 8篇 |
数学 | 25991篇 |
物理学 | 63671篇 |
出版年
2021年 | 1549篇 |
2020年 | 1887篇 |
2019年 | 1878篇 |
2018年 | 2228篇 |
2017年 | 2052篇 |
2016年 | 4028篇 |
2015年 | 3432篇 |
2014年 | 4000篇 |
2013年 | 10845篇 |
2012年 | 9849篇 |
2011年 | 11533篇 |
2010年 | 7063篇 |
2009年 | 6864篇 |
2008年 | 10490篇 |
2007年 | 10458篇 |
2006年 | 9752篇 |
2005年 | 9142篇 |
2004年 | 8032篇 |
2003年 | 6787篇 |
2002年 | 6080篇 |
2001年 | 6644篇 |
2000年 | 4962篇 |
1999年 | 3685篇 |
1998年 | 2737篇 |
1997年 | 2749篇 |
1996年 | 2795篇 |
1995年 | 2536篇 |
1994年 | 2493篇 |
1993年 | 2388篇 |
1992年 | 2712篇 |
1991年 | 2582篇 |
1990年 | 2308篇 |
1989年 | 2255篇 |
1988年 | 2259篇 |
1987年 | 2170篇 |
1986年 | 2046篇 |
1985年 | 3114篇 |
1984年 | 3082篇 |
1983年 | 2417篇 |
1982年 | 2672篇 |
1981年 | 2537篇 |
1980年 | 2479篇 |
1979年 | 2408篇 |
1978年 | 2483篇 |
1977年 | 2385篇 |
1976年 | 2376篇 |
1975年 | 2347篇 |
1974年 | 2251篇 |
1973年 | 2316篇 |
1972年 | 1291篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Massoumi Sina Challamel Noël Lerbet Jean Wautier Antoine Nicot François Darve Félix 《Meccanica》2022,57(8):2043-2066
Meccanica - This study is an attempt towards a better understanding of the length scale effects on the bending response of the granular beams. To this aim, a unidimensional discrete granular chain... 相似文献
2.
Ribeiro Sabrina Dias Meneguin Andria Bagliotti Barud Hernane da Silva Silva Jhonatan Miguel Oliveira Rafael L. Asuno Rosana Maria Nascimento de Tormin Thiago Faria Muoz Rodrigo Alejandro Abarza Filho Guimes Rodrigues Ribeiro Clovis Augusto 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7265-7275
Journal of Thermal Analysis and Calorimetry - Cellophane film production generates cellulosic residues from scraps, edges, and low-quality films. In this work, cellophane was used as a raw material... 相似文献
3.
Tagouegni Senghor Fotsa-Ngaffo Fernande Kenfack-Jiotsa Aurélien 《Optical and Quantum Electronics》2022,54(3):1-57
Optical and Quantum Electronics - In the past few decades, the academic research and industrial synergy is dramatically accelerating to conceptualize high data rate services. The congestion in the... 相似文献
4.
Fernández Julio R. Gallego Inés Jiménez-Losada Andrés Ordóñez Manuel 《Fuzzy Optimization and Decision Making》2022,21(4):531-551
Fuzzy Optimization and Decision Making - Cost-allocation problems in a fixed network are concerned with distributing the costs for use by a group of clients who cooperate in order to reduce such... 相似文献
5.
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.
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
7.
Caillau Jean-Baptiste Djema Walid Gouzé Jean-Luc Maslovskaya Sofya Pomet Jean-Baptiste 《Journal of Optimization Theory and Applications》2022,194(2):375-407
Journal of Optimization Theory and Applications - We consider the problem of maximization of metabolite production in bacterial cells formulated as a dynamical optimal control problem (DOCP).... 相似文献
8.
9.
Journal of Analytical Chemistry - The review considers the historical aspects of the formation and development of bioelectrochemistry and some issues of the analytical application of... 相似文献
10.
Mathematical Programming - Minimizing a convex function of a measure with a sparsity-inducing penalty is a typical problem arising, e.g., in sparse spikes deconvolution or two-layer neural networks... 相似文献