全文获取类型
收费全文 | 6848篇 |
免费 | 160篇 |
国内免费 | 10篇 |
专业分类
化学 | 4422篇 |
晶体学 | 66篇 |
力学 | 83篇 |
数学 | 933篇 |
物理学 | 1514篇 |
出版年
2021年 | 47篇 |
2020年 | 62篇 |
2019年 | 65篇 |
2016年 | 97篇 |
2015年 | 89篇 |
2014年 | 110篇 |
2013年 | 218篇 |
2012年 | 190篇 |
2011年 | 239篇 |
2010年 | 167篇 |
2009年 | 123篇 |
2008年 | 210篇 |
2007年 | 209篇 |
2006年 | 197篇 |
2005年 | 229篇 |
2004年 | 201篇 |
2003年 | 180篇 |
2002年 | 155篇 |
2001年 | 152篇 |
2000年 | 154篇 |
1999年 | 97篇 |
1998年 | 64篇 |
1997年 | 66篇 |
1996年 | 113篇 |
1995年 | 81篇 |
1994年 | 112篇 |
1993年 | 92篇 |
1992年 | 86篇 |
1991年 | 93篇 |
1990年 | 78篇 |
1989年 | 75篇 |
1988年 | 78篇 |
1987年 | 95篇 |
1986年 | 98篇 |
1985年 | 98篇 |
1984年 | 102篇 |
1983年 | 84篇 |
1982年 | 95篇 |
1981年 | 109篇 |
1980年 | 85篇 |
1979年 | 78篇 |
1978年 | 98篇 |
1977年 | 96篇 |
1976年 | 92篇 |
1975年 | 81篇 |
1974年 | 87篇 |
1973年 | 65篇 |
1971年 | 54篇 |
1968年 | 49篇 |
1967年 | 62篇 |
排序方式: 共有7018条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
F. Meyer 《Fresenius' Journal of Analytical Chemistry》1885,24(1):617
Ohne Zusammenfassung 相似文献
5.
Employing a cleavable carbohydrate–peptide linker, a new strategy for single-bead analysis of multivalent cyclic neoglycopeptides based on Edman degradation is described. Edman degradation of glycopeptides is hampered by the acid lability of the glycosidic bond and potential incompatibilities of phenylthiohydantoin (PTH) derivatives of glycosylated amino acids with PTH derivatives of the proteinogenic amino acids. To overcome this problem, carbohydrates are detached from the cyclopeptide templates before single-bead analysis, allowing for micro sequencing under routine conditions. With this strategy, application of multivalent cyclic neoglycopeptides in split-mix libraries with a subsequent screening process becomes possible for the first time. 相似文献
6.
J. R. Lindle W. W. Bewley I. Vurgaftman J. R. Meyer J. L. Johnson M. L. Thomas W. E. Tennant 《Physica E: Low-dimensional Systems and Nanostructures》2004,20(3-4):558
A self-referencing, optical modulation technique was used to measure the negative luminescence efficiencies of an array of mid-wave infrared HgCdTe photodiodes with cutoff wavelength 4.6 μm as a function of sample temperature. The internal efficiency at a wavelength of 4 μm was 93% at 295 K, and nearly independent of temperature in the 240–300 K range. This corresponds to an apparent temperature reduction >50 K at room temperature and >30 K at 240 K. Moreover, the reverse-bias saturation current density was only 0.13 A/cm2. The measured transmission and emission spectra were simulated using empirical HgCdTe absorption formulas from the literature. 相似文献
7.
Geerk J. Linker G. Meyer O. Politis C. Ratzel F. Smithey R. Strehlau B. Xiong G. C. 《Zeitschrift für Physik B Condensed Matter》1987,67(4):507-511
Thin superconducting films of La1.8Sr0.2CuO4 have been prepared by magnetron sputter deposition and subsequent temperature treatment. The composition of the films has been determined by Rutherford backscattering and the structure by thin film X-ray diffraction. The onset of superconductivity was about 32 K and the midpoint near 28 K. Defect production in the films by He ion bombardment revealed a drasticT
c
reduction with a sensitivity similar to that observed in the Chevrel phases. Oxygen implantation and subsequent annealing led to an enhancement of theT
c
onset. 相似文献
8.
In spherically symmetric systems, in spite of Birkhoff's Theorem, the rates of clocks in vacuum regions on either side of moving mass shells must be continually readjusted to stay in synchrony. This shows up as time-dependence of the metric in terms of the globally meaningful time coordinate. 相似文献
9.
A. Craig W. H. Jacobson A. Meyer N. Welwart A. Seuthe H. N. Marr B. S. Evans G. E. F. Lundell J. A. Scherrer E. Stelling F. J. Mück A. Kling A. Lassieur L. Bertiaux C. C. Bissett P. de Pauw J. Heslinga A. Bartsch R. E. Lee W. H. Fegeley F. H. Reichel und E. Saz 《Fresenius' Journal of Analytical Chemistry》1927,71(1-2):83-90
Ohne Zusammenfassung 相似文献
10.
Andrzej Dabrowski Erich Robens Peter Klobes Klaus Meyer Przemyslaw Podkocielny 《Particle & Particle Systems Characterization》2003,20(5):311-322
Since a comprehensive survey published in 1999 [1] much work was done in standardizing measuring methods to characterize the surface geometry of dispersed and/or porous solids and to certify reference materials. The present paper is an extension of a short communication [2]. It gives a survey on existing standards and reports on new drafts and proposals. 相似文献