全文获取类型
收费全文 | 12008篇 |
免费 | 1825篇 |
国内免费 | 1081篇 |
专业分类
化学 | 8794篇 |
晶体学 | 478篇 |
力学 | 1344篇 |
综合类 | 41篇 |
数学 | 288篇 |
物理学 | 3969篇 |
出版年
2024年 | 14篇 |
2023年 | 151篇 |
2022年 | 298篇 |
2021年 | 416篇 |
2020年 | 702篇 |
2019年 | 473篇 |
2018年 | 419篇 |
2017年 | 438篇 |
2016年 | 699篇 |
2015年 | 690篇 |
2014年 | 728篇 |
2013年 | 944篇 |
2012年 | 647篇 |
2011年 | 810篇 |
2010年 | 717篇 |
2009年 | 719篇 |
2008年 | 795篇 |
2007年 | 814篇 |
2006年 | 714篇 |
2005年 | 561篇 |
2004年 | 556篇 |
2003年 | 557篇 |
2002年 | 373篇 |
2001年 | 317篇 |
2000年 | 252篇 |
1999年 | 189篇 |
1998年 | 172篇 |
1997年 | 121篇 |
1996年 | 106篇 |
1995年 | 69篇 |
1994年 | 75篇 |
1993年 | 52篇 |
1992年 | 52篇 |
1991年 | 48篇 |
1990年 | 41篇 |
1989年 | 31篇 |
1988年 | 17篇 |
1987年 | 21篇 |
1986年 | 23篇 |
1985年 | 15篇 |
1984年 | 17篇 |
1983年 | 18篇 |
1982年 | 14篇 |
1981年 | 7篇 |
1980年 | 2篇 |
1979年 | 6篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1971年 | 6篇 |
1957年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 610 毫秒
991.
992.
993.
B. Ruzicka A. Brglez B. Malic L. Degiorgi D. Mihailovic 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,13(2):205-208
We present the results of a dc transport and optical investigation of WO3 and NaxWO3 with x
=0.01. Upon Na-doping we find a (Drude) metallic component in the optical conductivity, while the transport data display a crossover
from an activated to a variable range hopping regime around 210 K. We suggest the possible formation of polarons (and bipolarons)
and speculate that superconductivity could be induced, provided the dc percolation threshold is achieved.
Received 28 March 2000 相似文献
994.
本文论述了用显微金刚石池研究高分子弹性材料,方法简便、快速和精确。 相似文献
995.
本文将报告对硅纳米线、多孔硅、Si C纳米棒和碳纳米管等一维纳米体系的本征拉曼光谱及其特征的研究结果 ,并讨论拉曼光谱在上述材料的几何和物理特性研究中的应用。 相似文献
996.
Lowe Terry C. Bishop Alan Burns Carol Hartford Allen Parkin Don Trewhella Jill 《Journal of nanoparticle research》2000,2(3):249-266
Research in the emerging field of nanoscale science and technology has grown steadily at Los Alamos National Laboratory since 1990. This article summarizes some of this work, examining research highlights within the seven key categories of nanoscience in which Los Alamos has ongoing projects, capabilities, and facilities: (1) Materials and chemistry, (2) Theory and modeling, (3) Bioscience, (4) Investigative tools and facilities, (5) Sensors and devices, (6) Synthesis and fabrication, and (7) Education and outreach. Future research horizons are indicated throughout while institutional strategies for advancing nanoscale science are summarized at the end. 相似文献
997.
Stephen R. Elliott C. N. R. Rao John M. Thomas 《Angewandte Chemie (International ed. in English)》1986,25(1):31-46
This article sets out to describe and account for the chemical and physical consequences of the presence of gross disorder in solids. Knowledge of the structure of such disordered materials is an obvious prerequisite to a further understanding of other properties and behavior, and our current knowledge of the structure of various noncrystalline systems is discussed together with the experimental techniques which need to be employed in order to obtain such information. The so-called glass transition, which takes place as a liquid is supercooled below the crystallization temperature, is discussed in terms of the various models which have been proposed to account for this phenomenon. The effect of noncrystallinity on electronic properties is also discussed, and we highlight new developments in the understanding of electron localization and transport processes. Finally, two applications of amorphous solids are considered in some detail: optical fibers for use in communication networks and “superionic” glasses for possible use in solid-state batteries. 相似文献
998.
L.Q. Cao 《Journal of Mathematical Analysis and Applications》2008,343(2):1103-1118
In this paper, we study the optimal control on the boundary for parabolic equations with rapidly oscillating coefficients arising from the heat transfer problems and the optimal control on the boundary of composite materials or porous media. The multiscale asymptotic expansion of the solution for the problem in the case without any constraints is presented. We derive the proofs of all convergence results. 相似文献
999.
1000.