全文获取类型
收费全文 | 676篇 |
免费 | 23篇 |
国内免费 | 94篇 |
专业分类
化学 | 18篇 |
力学 | 6篇 |
综合类 | 13篇 |
数学 | 722篇 |
物理学 | 34篇 |
出版年
2024年 | 3篇 |
2023年 | 3篇 |
2022年 | 6篇 |
2021年 | 11篇 |
2020年 | 20篇 |
2019年 | 21篇 |
2018年 | 25篇 |
2017年 | 33篇 |
2016年 | 5篇 |
2015年 | 6篇 |
2014年 | 14篇 |
2013年 | 231篇 |
2012年 | 7篇 |
2011年 | 25篇 |
2010年 | 8篇 |
2009年 | 37篇 |
2008年 | 29篇 |
2007年 | 40篇 |
2006年 | 24篇 |
2005年 | 26篇 |
2004年 | 25篇 |
2003年 | 35篇 |
2002年 | 21篇 |
2001年 | 24篇 |
2000年 | 27篇 |
1999年 | 15篇 |
1998年 | 23篇 |
1997年 | 17篇 |
1996年 | 8篇 |
1995年 | 11篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 4篇 |
1988年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有793条查询结果,搜索用时 375 毫秒
151.
Inside Cover: Kinetics of Reactive Modules Adds Discriminative Dimensions for Selective Cell Imaging (ChemPhysChem 10/2016)
下载免费PDF全文
![点击此处可从《Chemphyschem》网站下载免费的PDF全文](/ch/ext_images/free.gif)
152.
We study the so-called weakly Koszul modules and characterise their Koszul duals. We show that the (adjusted) associated graded module of a weakly Koszul module exactly determines the homology modules of the Koszul dual. We give an example of a quasi-Koszul module which is not weakly Koszul. 相似文献
153.
We give conditions under which an n-star module extends to an n-star module, or an n-tilting module, over a ring extension R of A. In case that R is a split extension of A by Q, we obtain that is a 1-tilting module (respectively, a 1-star module) if and only if is a 1-tilting module (respectively, a 1-star module) and generates both and (respectively, generates ), where is an injective cogenerator in the category of all left A-modules. These extend results in [I. Assem, N. Marmaridis, Tilting modules over split-by-nilpotent extensions, Comm. Algebra 26 (1998) 1547–1555; K.R. Fuller, *-Modules over ring extensions, Comm. Algebra 25 (1997) 2839–2860] by removing the restrictions on R and Q. 相似文献
154.
冯国 《纯粹数学与应用数学》2007,23(2):221-225,230
利用加权Ditzin-Totik 光滑模ω2φλ(f;t)w,借助Peetre K-泛函研究了Meyer-K(o)nig-Zeller算子,给出其特征刻画. 相似文献
155.
Rü diger Gö bel Saharon Shelah 《Proceedings of the American Mathematical Society》2007,135(6):1641-1649
A module is called absolutely indecomposable if it is directly indecomposable in every generic extension of the universe. We want to show the existence of large abelian groups that are absolutely indecomposable. This will follow from a more general result about -modules over a large class of commutative rings with endomorphism ring which remains the same when passing to a generic extension of the universe. It turns out that `large' in this context has a precise meaning, namely being smaller than the first -Erdos cardinal defined below. We will first apply a result on large rigid valuated trees with a similar property established by Shelah in 1982, and will prove the existence of related `-modules' (-modules with countably many distinguished submodules) and finally pass to -modules. The passage through -modules has the great advantage that the proofs become very transparent essentially using a few `linear algebra' arguments also accessible for graduate students. The result closes a gap of Eklof and Shelah (1999) and Eklof and Mekler (2002), provides a good starting point for Fuchs and Göbel, and gives a new construction of indecomposable modules in general using a counting argument.
156.
157.
Let A be a noetherian commutative Z[1/2]-algebra of Krull dimension d and let P be a projective A-module of rank d. We use derived Grothendieck-Witt groups and Euler classes to detect some obstructions for P to split off a free factor of rank one. If d?3, we show that the vanishing of its Euler class in the corresponding Grothendieck-Witt group is a necessary and sufficient condition for P to have a free factor of rank one. If d is odd, we also get some results in that direction. If A is regular, we show that the Chow-Witt groups defined by Morel and Barge appear naturally as some homology groups of a Gersten-type complex in Grothendieck-Witt theory. From this, we deduce that if d=3 then the vanishing of the Euler class of P in the corresponding Chow-Witt group is a necessary and sufficient condition for P to have a free factor of rank one. 相似文献
158.
Ghislain Fourier 《Advances in Mathematics》2009,222(3):1080-1293
We provide combinatorial models for all Kirillov-Reshetikhin crystals of nonexceptional type, which were recently shown to exist. For types , , we rely on a previous construction using the Dynkin diagram automorphism which interchanges nodes 0 and 1. For type we use a Dynkin diagram folding and for types , a similarity construction. We also show that for types and the analog of the Dynkin diagram automorphism exists on the level of crystals. 相似文献
159.
Raghad Saeed Hasan Shelan Khasro Tawfeeq Nahla Qader Mohammed Ahmed Ismael Khaleel 《Chinese Journal of Physics (Taipei)》2018,56(1):385-391
True random number generators are essential components for communications to be confidentially secured. In this paper a new method is proposed to generate random sequences of numbers based on the difference of the arrival times of photons detected in a coincidence window between two single-photon counting modules. 相似文献
160.
介绍非有限阶化无中心Virasoro超代数的概念,并通过具体计算给出了非有限阶化无中心Virasoro超代数的一类中间序列模. 相似文献