全文获取类型
收费全文 | 1481篇 |
免费 | 59篇 |
国内免费 | 2篇 |
专业分类
化学 | 986篇 |
晶体学 | 46篇 |
力学 | 19篇 |
数学 | 187篇 |
物理学 | 304篇 |
出版年
2023年 | 15篇 |
2022年 | 13篇 |
2021年 | 20篇 |
2020年 | 40篇 |
2019年 | 31篇 |
2018年 | 14篇 |
2017年 | 22篇 |
2016年 | 41篇 |
2015年 | 29篇 |
2014年 | 53篇 |
2013年 | 81篇 |
2012年 | 64篇 |
2011年 | 76篇 |
2010年 | 30篇 |
2009年 | 34篇 |
2008年 | 59篇 |
2007年 | 50篇 |
2006年 | 49篇 |
2005年 | 32篇 |
2004年 | 29篇 |
2003年 | 26篇 |
2002年 | 15篇 |
2001年 | 15篇 |
2000年 | 22篇 |
1999年 | 18篇 |
1997年 | 19篇 |
1995年 | 14篇 |
1994年 | 9篇 |
1993年 | 13篇 |
1992年 | 10篇 |
1991年 | 11篇 |
1989年 | 17篇 |
1988年 | 15篇 |
1987年 | 17篇 |
1986年 | 18篇 |
1985年 | 12篇 |
1984年 | 24篇 |
1983年 | 16篇 |
1982年 | 9篇 |
1981年 | 19篇 |
1980年 | 19篇 |
1979年 | 16篇 |
1978年 | 14篇 |
1976年 | 16篇 |
1975年 | 9篇 |
1974年 | 14篇 |
1927年 | 10篇 |
1925年 | 11篇 |
1908年 | 9篇 |
1907年 | 10篇 |
排序方式: 共有1542条查询结果,搜索用时 15 毫秒
1.
Designs, Codes and Cryptography - We study security functions which can serve to establish semantic security for the two central problems of information-theoretic security: the wiretap channel, and... 相似文献
2.
Dr. Liat Avram Dr. Václav Havel Ronit Shusterman-Krush Dr. Mark A. Iron Dr. Moritz Zaiss Prof. Vladimír Šindelář Dr. Amnon Bar-Shir 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(7):1687-1690
The accumulated knowledge regarding molecular architectures is based on established, reliable, and accessible analytical tools that provide robust structural and functional information on assemblies. However, both the dynamicity and low population of noncovalently interacting moieties within studied molecular systems limit the efficiency and accuracy of traditional methods. Herein, the use of a saturation transfer-based NMR approach to study the dynamic binding characteristics of an anion to a series of synthetic receptors derived from bambusuril macrocycles is demonstrated. The exchange rates of BF4− are mediated by the side chains on the receptor (100 s−1<kex<5000 s−1), which play a critical role in receptor-anion binding dynamics. The signal amplification obtained with this approach allows for the identification of different types of intermolecular interactions between the receptor and the anion, something that could not have been detected by techniques hitherto used to study molecular assemblies. These findings, which are supported by a computational molecular dynamic study, demonstrate the uniqueness and added value of this NMR method. 相似文献
3.
Moritz Kohn 《Monatshefte für Chemie / Chemical Monthly》1923,43(5):373-376
Ohne ZusammenfassungHerrn Ingenieur E. Hofmann danke ich fÜr seine bewährte UnterstÜtzung. 相似文献
4.
Operators on manifolds with corners that have base configurations with geometric singularities can be analysed in the frame of a conormal symbolic structure which is in spirit similar to the one for conical singularities of Kondrat'ev's work. Solvability of elliptic equations and asymptotics of solutions are determined by meromorphic conormal symbols. We study the case when the base has edge singularities which is a natural assumption in a number of applications. There are new phenomena, caused by a specific kind of higher degeneracy of the underlying symbols. We introduce an algebra of meromorphic edge operators that depend on complex parameters and investigate meromorphic inverses in the parameter-dependent elliptic case. Among the examples are resolvents of elliptic differential operators on manifolds with edges. 相似文献
5.
A. G. Milekhin A. I. Nikiforov M. Yu. Ladanov O. P. Pchelyakov S. Schulze D. R. T. Zahn 《Physics of the Solid State》2004,46(1):92-96
This paper reports on the results of resonant Raman scattering investigations of the fundamental vibrations in Ge/Si structures with strained and relaxed germanium quantum dots. Self-assembled strained Ge/Si quantum dots are grown by molecular-beam epitaxy on Si(001) substrates. An ultrathin SiO2 layer is grown prior to the deposition of a germanium layer with the aim of forming relaxed germanium quantum dots. The use of resonant Raman scattering (selective with respect to quantum dot size) made it possible to assign unambiguously the line observed in the vicinity of 300 cm?1 to optical phonons confined in relaxed germanium quantum dots. The influence of confinement effects and mechanical stresses on the vibrational spectra of the structures with germanium quantum dots is analyzed. 相似文献
6.
Julie Clutterbuck Oliver C. Schnürer Felix Schulze 《Calculus of Variations and Partial Differential Equations》2007,29(3):281-293
We prove stability of rotationally symmetric translating solutions to mean curvature flow. For initial data that converge
spatially at infinity to such a soliton, we obtain convergence for large times to that soliton without imposing any decay
rates.
The authors are members of SFB 647/B3 “Raum – Zeit – Materie: Singularity Structure, Long-time Behaviour and Dynamics of Solutions
of Non-linear Evolution Equations”. 相似文献
7.
N. Ahmad C. Nanjundayya W. G. Chace M. A. Ssobolew M. M. Tschilikin A. T. Iwanowa F. Kalmanowitsch A. Kolotyrewa C. F. Cross E. J. Bevan A. Eavenson J. W. Creely J. H. Skinkle O. Viertel A. J. Hall W. N. Udalskaja D. A. Clibbens A. H. Little Karin Schulze S. M. Edelstein E. Lindemann F. Schütz W. Klauditz P. Winterfeld F. H. Guernsay L. T. Howells F. Schroeder R. Finlay G. Hasse Niederhauser H. Ris R. D. Nutting W. Lesnianski F. Fabrowicz und Coch 《Fresenius' Journal of Analytical Chemistry》1938,115(1-2):51-57
Ohne Zusammenfassung 相似文献
8.
9.
C. Mahr H. Bergmann P. Zuman J. Sunkel K. -J. Range K. -H. König W. Schermann G. Manecke A. Sippel E. Best K. Hartl J. Volke H. Kübler P. Moritz H. H. Pfeiffer E. Knickmann H. Lüken 《Colloid and polymer science》1967,218(2):158-171
Ohne Zusammenfassung 相似文献
10.