全文获取类型
收费全文 | 296篇 |
免费 | 1篇 |
国内免费 | 6篇 |
专业分类
化学 | 109篇 |
晶体学 | 1篇 |
力学 | 21篇 |
数学 | 133篇 |
物理学 | 39篇 |
出版年
2022年 | 2篇 |
2021年 | 5篇 |
2019年 | 7篇 |
2018年 | 7篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 5篇 |
2014年 | 8篇 |
2013年 | 16篇 |
2012年 | 14篇 |
2011年 | 11篇 |
2010年 | 10篇 |
2009年 | 20篇 |
2008年 | 21篇 |
2007年 | 17篇 |
2006年 | 23篇 |
2005年 | 12篇 |
2004年 | 9篇 |
2003年 | 6篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1993年 | 6篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1984年 | 3篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 7篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1972年 | 3篇 |
1968年 | 2篇 |
1965年 | 3篇 |
1964年 | 3篇 |
1963年 | 2篇 |
1942年 | 1篇 |
1939年 | 1篇 |
1935年 | 2篇 |
排序方式: 共有303条查询结果,搜索用时 194 毫秒
81.
Yoshimi Egawa Ralph J. Faudree Ervin Györi Yoshiyasu Ishigami Richard H. Schelp Hong Wang 《Graphs and Combinatorics》2000,16(1):81-92
Dirac and Ore-type degree conditions are given for a graph to contain vertex disjoint cycles each of which contains a previously
specified edge. One set of conditions is given that imply vertex disjoint cycles of length at most 4, and another set of conditions
are given that imply the existence of cycles that span all of the vertices of the graph (i.e. a 2-factor). The conditions
are shown to be sharp and give positive answers to conjectures of Enomoto in [3] and Wang in [5].
Revised: July 28, 1999 相似文献
82.
Preclassification of Broadband and Sparse Infrared Data by Multiplicative Signal Correction Approach
Hafeez Ur Rehman Valeria Tafintseva Boris Zimmermann Johanne Heitmann Solheim Vesa Virtanen Rubina Shaikh Ervin Nippolainen Isaac Afara Simo Saarakkala Lassi Rieppo Patrick Krebs Polina Fomina Boris Mizaikoff Achim Kohler 《Molecules (Basel, Switzerland)》2022,27(7)
Preclassification of raw infrared spectra has often been neglected in scientific literature. Separating spectra of low spectral quality, due to low signal-to-noise ratio, presence of artifacts, and low analyte presence, is crucial for accurate model development. Furthermore, it is very important for sparse data, where it becomes challenging to visually inspect spectra of different natures. Hence, a preclassification approach to separate infrared spectra for sparse data is needed. In this study, we propose a preclassification approach based on Multiplicative Signal Correction (MSC). The MSC approach was applied on human and the bovine knee cartilage broadband Fourier Transform Infrared (FTIR) spectra and on a sparse data subset comprising of only seven wavelengths. The goal of the preclassification was to separate spectra with analyte-rich signals (i.e., cartilage) from spectra with analyte-poor (and high-matrix) signals (i.e., water). The human datasets 1 and 2 contained 814 and 815 spectra, while the bovine dataset contained 396 spectra. A pure water spectrum was used as a reference spectrum in the MSC approach. A threshold for the root mean square error () was used to separate cartilage from water spectra for broadband and the sparse spectral data. Additionally, standard noise-to-ratio and principle component analysis were applied on broadband spectra. The fully automated MSC preclassification approach, using water as reference spectrum, performed as well as the manual visual inspection. Moreover, it enabled not only separation of cartilage from water spectra in broadband spectral datasets, but also in sparse datasets where manual visual inspection cannot be applied. 相似文献
83.
Dorin Bucur Eduard Feireisl Šárka Ne?asová Joerg Wolf 《Journal of Differential Equations》2008,244(11):2890-2908
We study the asymptotic behavior of solutions to the incompressible Navier-Stokes system considered on a sequence of spatial domains, whose boundaries exhibit fast oscillations with amplitude and characteristic wave length proportional to a small parameter. Imposing the complete slip boundary conditions we show that in the asymptotic limit the fluid sticks completely to the boundary provided the oscillations are non-degenerate, meaning not oriented in a single direction. 相似文献
84.
85.
The effect of superconducting fluctuations on quasi-particle current of tunneling junction is discussed. The anomalous contribution in tunneling current from interacting across the barrier fluctuations is found. It gives rise to pseudogap minimum in Rd(V). Similar dependence is observed experimentally in NbN-I-Pb junctions. Reasons are given to suggest that there is some ultrathin layer on the surface of NbN films whose properties drastically differ from the bulk one. 相似文献
86.
87.
E. Wendehorst E. Knoche S. S. Nametkin E. A. Robinson M. J. Herbrich G. Egloff J. C. Morrell P. Truesdell O. C. Bridgeman J. C. Molitor T. H. Rogers V. Voorhees H. O. Ervin E. R. Gillis C. C. Minter und A. Dongescu 《Fresenius' Journal of Analytical Chemistry》1935,102(7-8):308-312
Ohne Zusammenfassung 相似文献
88.
This Note deals with the identifiability of non-smooth defects by boundary measurements. We prove the uniqueness of the detection by two measurements for arbitrary closed sets satisfying quasi-everywhere a conductivity assumption. This assumption is satisfied by a large class of compact sets, including all the sets which can be written as an arbitrary union of continua of positive diameter. The conductivity is a new regularity concept which is related to the thickness of the set and is to be compared to the Wiener regularity. In order to rigorously justify the numerical approach by the finite element method, we provide a stability result without any a priori smoothness assumptions. To cite this article: Z. Belhachmi, D. Bucur, C. R. Acad. Sci. Paris, Ser. I 340 (2005). 相似文献
89.
90.