全文获取类型
收费全文 | 381篇 |
免费 | 31篇 |
国内免费 | 62篇 |
专业分类
化学 | 27篇 |
力学 | 18篇 |
综合类 | 12篇 |
数学 | 381篇 |
物理学 | 36篇 |
出版年
2024年 | 1篇 |
2023年 | 4篇 |
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 13篇 |
2019年 | 14篇 |
2018年 | 9篇 |
2017年 | 16篇 |
2016年 | 8篇 |
2015年 | 12篇 |
2014年 | 9篇 |
2013年 | 45篇 |
2012年 | 14篇 |
2011年 | 14篇 |
2010年 | 15篇 |
2009年 | 18篇 |
2008年 | 23篇 |
2007年 | 36篇 |
2006年 | 21篇 |
2005年 | 20篇 |
2004年 | 18篇 |
2003年 | 18篇 |
2002年 | 25篇 |
2001年 | 16篇 |
2000年 | 15篇 |
1999年 | 19篇 |
1998年 | 11篇 |
1997年 | 12篇 |
1996年 | 5篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 6篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1987年 | 1篇 |
1985年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有474条查询结果,搜索用时 15 毫秒
81.
陈历敏 《纯粹数学与应用数学》2005,21(4):317-318,324
我们对带零逆半群定义了0-对偶预同态的概念,给出并证明了0-对偶预同态的一个等价条件. 相似文献
82.
We prove that the free metabelian Lie algebra M 3 of rank 3 over an arbitrary field K admits strictly nontame primitive elements. 相似文献
83.
研究了围长为2的无限布尔方阵的本原性,通过无限有向图D(A)的直径给出了这类矩阵的本原指数的上确界,最后证明了直径小于等于d且围长为2的本原无限布尔方阵所构成的矩阵类的本原指数集为Ed^0={2,3,…,3d}. 相似文献
84.
研究了p是正奇素数的情况下,有限域的原根在剩余理论中的应用.利用有限域Fp上原根的性质,给出了一类集合与平方剩余之间的关系,获得了这类集合所包含元素个数之间的关系,并且这个结论把关于这方面的结果从r=0推广到了r=0和2. 相似文献
85.
Curves in the Minkowski space are very well suited to describe the medial axis transform (MAT) of planar domains. Among them, Minkowski Pythagorean hodograph
(MPH) curves correspond to domains where both the boundaries and their offsets admit rational parameterizations (Choi et al.,
Comput Aided Design 31:59–72, 1999; Moon, Comput Aided Geom Design 16:739–753; 1999). We construct MPH quintics which interpolate two points with associated first derivative vectors and analyze the properties
of the system of solutions, including the approximation order of the ‘best’ interpolant.
相似文献
86.
FRIED Michael D. 《中国科学 数学(英文版)》2012,55(1):1-72
Davenport’s Problem asks:What can we expect of two polynomials,over Z,with the same ranges on almost all residue class fields? This stood out among many separated variable problems posed by Davenport,Lewis and Schinzel.By bounding the degrees,but expanding the maps and variables in Davenport’s Problem,Galois stratification enhanced the separated variable theme,solving an Ax and Kochen problem from their Artin Conjecture work.Denef and Loeser applied this to add Chow motive coefficients to previously introduced zeta functions on a diophantine statement.By restricting the variables,but leaving the degrees unbounded,we found the striking distinction between Davenport’s problem over Q,solved by applying the Branch Cycle Lemma,and its generalization over any number field,solved by using the simple group classification.This encouraged Thompson to formulate the genus 0 problem on rational function monodromy groups.Guralnick and Thompson led its solution in stages.We look at two developments since the solution of Davenport’s problem.Stemming from MacCluer’s 1967 thesis,identifying a general class of problems,including Davenport’s,as monodromy precise.R(iemann)E(xistence)T(heorem)’s role as a converse to problems generalizing Davenport’s,and Schinzel’s (on reducibility).We use these to consider:Going beyond the simple group classification to handle imprimitive groups,and what is the role of covers and correspondences in going from algebraic equations to zeta functions with Chow motive coefficients. 相似文献
87.
设G是一个2-(v,k,l)设计的可解区传递自同构群,且k≥3.若v〉(k(k-1)/2-1)^2,则v=p^n,其中p为素数.进一步,当n为两个不同奇素数幂的乘积时,G是旗传递的或者G≤AГL(1,p^n). 相似文献
88.
By considering the fluctuation of grand potential Ω around equilibrium with respect to small one-particle density fluctuations δρα\vec{r}, the phase instability of restricted primitive model (RPM) of ionic systems is investigated. We use the integral equation theory to calculate the direct correlation functions in the reference hypernetted chainapproximation and obtain the spinodal line of RPM. Our analysis explicitly indicates that the gas-fluid phase instability is induced by k=0 fluctuation mode, while the fluid-solid phase instability is related to k≠0 fluctuation modes. The spinodal line isqualitatively consistent with the result of computer simulations by others. 相似文献
89.
A graph Г is said to be G-locally primitive, where G is a subgroup of automorphisms of Г, if the stabiliser Ga of a vertex α acts primitively on the set Г( α ) of vertices of Г adjacent to α. For a finite non-abelian simple group L
and a Cayley subset S of L, suppose that L ⊴ G ⩽ Aut( L), and the Cayley graph Г = Cay ( L, S) is G-locally primitive. In
this paper we prove that L is a simple group of Lie type, and either the valency of Г is an add prine divisor of |Out(L)|, orL =PΩ
8
+
(q) and Г has valency 4. In either cases, it is proved that the full automorphism group of Г is also almost simple with the
same socle L. 相似文献
90.
素GPI-环广义形心扩张的本原性 总被引:1,自引:0,他引:1
类似于中心扩张,本文引入了广义形心扩张的概念,且研究了广义形心扩张的本原性。 相似文献