全文获取类型
收费全文 | 18663篇 |
免费 | 454篇 |
国内免费 | 271篇 |
专业分类
化学 | 1994篇 |
晶体学 | 57篇 |
力学 | 212篇 |
综合类 | 114篇 |
数学 | 15919篇 |
物理学 | 1092篇 |
出版年
2023年 | 40篇 |
2022年 | 169篇 |
2021年 | 134篇 |
2020年 | 116篇 |
2019年 | 440篇 |
2018年 | 518篇 |
2017年 | 265篇 |
2016年 | 217篇 |
2015年 | 251篇 |
2014年 | 499篇 |
2013年 | 1027篇 |
2012年 | 628篇 |
2011年 | 1037篇 |
2010年 | 1004篇 |
2009年 | 1332篇 |
2008年 | 1374篇 |
2007年 | 1307篇 |
2006年 | 979篇 |
2005年 | 649篇 |
2004年 | 561篇 |
2003年 | 510篇 |
2002年 | 423篇 |
2001年 | 407篇 |
2000年 | 446篇 |
1999年 | 464篇 |
1998年 | 435篇 |
1997年 | 383篇 |
1996年 | 360篇 |
1995年 | 375篇 |
1994年 | 373篇 |
1993年 | 312篇 |
1992年 | 277篇 |
1991年 | 218篇 |
1990年 | 212篇 |
1989年 | 233篇 |
1988年 | 144篇 |
1987年 | 129篇 |
1986年 | 155篇 |
1985年 | 143篇 |
1984年 | 150篇 |
1983年 | 76篇 |
1982年 | 141篇 |
1981年 | 91篇 |
1980年 | 115篇 |
1979年 | 79篇 |
1978年 | 86篇 |
1977年 | 46篇 |
1976年 | 29篇 |
1974年 | 6篇 |
1973年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
Mauricio D Garay 《Topology》2004,43(5):1081-1088
We introduce a cohomological approach to isochore deformation problems. We use this formulation in order to prove an isochore versal deformation theorem for holomorphic function germs. 相似文献
122.
We provide a proof of Connes’ formula for a representative of the Hochschild class of the Chern character for (p,∞)-summable spectral triples. Our proof is valid for all semifinite von Neumann algebras, and all integral p?1. We employ the minimum possible hypotheses on the spectral triples. 相似文献
123.
Aleksey Zinger 《Topology》2004,43(4):793-829
We give a formula computing the number of one-nodal rational curves that pass through an appropriate collection of constraints in a complex projective space. The formula involves intersections of tautological classes on moduli spaces of stable rational maps. We combine the methods and results from three different papers. 相似文献
124.
The aim of this note is to generalize and apply results on matrix continued fractions representing the solution of discrete matrix Riccati equations. Assuming uniform bounds for the norm of the matrix coefficients of the continued fraction, the minimal and maximal solutions of the corresponding algebraic Riccati equation can be accurately enclosed. 相似文献
125.
David Hoff 《Journal of Mathematical Fluid Mechanics》2005,7(3):315-338
We prove the global existence of weak solutions of the Navier–Stokes equations of compressible flow in a half-space with the boundary condition proposed by Navier: the velocity on the boundary is proportional to the tangential component of the stress. This boundary condition allows for the determination of the scalar function in the Helmholtz decomposition of the acceleration density, which in turn is crucial in obtaining pointwise bounds for the density. Initial data and solutions are small in energy-norm with nonnegative densities having arbitrarily large sup-norm. These results generalize previous results for solutions in the whole space and are the first for solutions in this intermediate regularity class in a region with a boundary. 相似文献
126.
For the minimal surfaces in Rn with Plateau boundary condition and establish the global existence and uniqueness of the flow as well as the continuous dependence of the initial datum. 相似文献
127.
Approximation of a laminated microstructure for a rotationally invariant,double well energy density 总被引:3,自引:0,他引:3
Mitchell Luskin 《Numerische Mathematik》1996,75(2):205-221
Summary. We give error estimates for the approximation of a laminated microstructure which minimizes the energy for a rotationally invariant, double well energy density . We present error estimates for the convergence of the deformation in the convergence of directional derivatives of the deformation in the “twin planes,” the weak convergence of the deformation
gradient, the convergence of the microstructure (or Young measure) of the deformation gradients, and the convergence of nonlinear
integrals of the deformation gradient.
Received July 25, 1995 / Revised version received November 20, 1995 相似文献
128.
Summary.
We consider a discontinuous Galerkin finite element method
applied in time to a model Volterra equation of the second kind.
A residual-based computable
Galerkin-error estimate is derived
for .
This estimate does not explicitly
contain the time step and therefore the time step
control must be based
on a heuristic criterion, the estimate can then be used to
demonstrate the integrity, or otherwise, of the finite element
solution. After performing some numerical experiments
we conclude that this approach is at least competetive
with classical discretizations since it is
computationally simple to implement,
but has the added advantage of
reliable error feedback.
Received June 25, 1995 相似文献
129.
Michael Bildhauer 《manuscripta mathematica》1998,97(3):389-406
H?lder continuity up to the free boundary is proved for minimizing solutions if they meet the supporting surface in an angle
which is bounded away from zero. The problem is localized by proving the continuity of the distance function, a result which
is also true for stationary points.
Received: 14 April 1998 相似文献
130.
This paper deals with the inversive congruential method with power of two modulusm for generating uniform pseudorandom numbers. Statistical independence properties of the generated sequences are studied based on the distribution of triples of successive pseudorandom numbers. It is shown that there exist parameters in the inversive congruential method such that the discrepancy of the corresponding point sets in the unit cube is of an order of magnitude at leastm
–1/3. The method of proof relies on a detailed analysis of certain rational exponential sums. 相似文献