全文获取类型
收费全文 | 8979篇 |
免费 | 563篇 |
国内免费 | 849篇 |
专业分类
化学 | 703篇 |
晶体学 | 2篇 |
力学 | 403篇 |
综合类 | 113篇 |
数学 | 7745篇 |
物理学 | 1425篇 |
出版年
2024年 | 17篇 |
2023年 | 128篇 |
2022年 | 119篇 |
2021年 | 120篇 |
2020年 | 191篇 |
2019年 | 215篇 |
2018年 | 188篇 |
2017年 | 241篇 |
2016年 | 218篇 |
2015年 | 211篇 |
2014年 | 401篇 |
2013年 | 693篇 |
2012年 | 352篇 |
2011年 | 480篇 |
2010年 | 435篇 |
2009年 | 547篇 |
2008年 | 629篇 |
2007年 | 663篇 |
2006年 | 570篇 |
2005年 | 543篇 |
2004年 | 432篇 |
2003年 | 420篇 |
2002年 | 323篇 |
2001年 | 293篇 |
2000年 | 259篇 |
1999年 | 258篇 |
1998年 | 237篇 |
1997年 | 222篇 |
1996年 | 157篇 |
1995年 | 102篇 |
1994年 | 84篇 |
1993年 | 71篇 |
1992年 | 62篇 |
1991年 | 64篇 |
1990年 | 36篇 |
1989年 | 35篇 |
1988年 | 39篇 |
1987年 | 23篇 |
1986年 | 34篇 |
1985年 | 44篇 |
1984年 | 32篇 |
1983年 | 20篇 |
1982年 | 25篇 |
1981年 | 35篇 |
1980年 | 19篇 |
1979年 | 26篇 |
1978年 | 25篇 |
1977年 | 17篇 |
1976年 | 16篇 |
1973年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
981.
M. Giusti G. Lecerf B. Salvy J.-C. Yakoubsohn 《Foundations of Computational Mathematics》2005,5(3):257-311
At the beginning of the 1980s, M. Shub and S. Smale developed a
quantitative analysis of Newton's method for multivariate analytic
maps. In particular, their α-theory gives an effective
criterion that ensures safe convergence to a simple isolated zero.
This criterion requires only information concerning the map at the
initial point of the iteration. Generalizing this theory to multiple
zeros and clusters of zeros is still a challenging problem. In this
paper we focus on one complex variable function. We study general
criteria for detecting clusters and analyze the convergence of
Schroder's iteration to a cluster. In the case of a multiple root,
it is well known that this convergence is quadratic. In the case of a
cluster with positive diameter, the convergence is still quadratic
provided the iteration is stopped sufficiently early. We propose a
criterion for stopping this iteration at a distance from the cluster
which is of the order of its diameter. 相似文献
982.
In this paper, existence criteria are established for the existence of periodic solutions of a second order sublinear differential equation with delay and forcing function. Our method is based on careful a priori estimation and continuation theorems, and our sublinear condition is an improvement of the boundedness condition in some recent results. 相似文献
983.
Suppose μ is a Radon measure on ℝ
d
, which may be non doubling. The only condition assumed on μ is a growth condition, namely, there is a constant C0>0 such that for all x∈supp(μ) and r>0, μ(B(x, r))⪯C0rn, where 0<n⪯d. We prove T1 theorem for non doubling measures with weak kernel conditions. Our approach yields new results
for kernels satisfying weakened regularity conditions, while recovering previously known Tolsa’s results. We also prove T1
theorem for Besov spaces on nonhomogeneous spaces with weak kernel conditions given in [7]. 相似文献
984.
In this paper, using the concept ofA-statistical convergence which is a regular (non-matrix) summability method, we obtain a general Korovkin type approximation
theorem which concerns the problem of approximating a functionf by means of a sequenceL
n
f of positive linear operators. 相似文献
985.
A Voronin-type discrete universality theorem for the L-functions of new forms is proved. 相似文献
986.
A.R.ELAMROUSS 《数学学报(英文版)》2005,21(1):129-142
This paper contains a generalization of the well-known Palais-Smale and Cerami compactness conditions. The compactness condition introduced is used to prove some general existence theorems for critical points. Some applications are given to differential equations. 相似文献
987.
Bilal Chanane. 《Mathematics of Computation》2005,74(252):1793-1801
The purpose in this paper is to compute the eigenvalues of Sturm-Liouville problems with quite general separated boundary conditions nonlinear in the eigenvalue parameter using the regularized sampling method, an improvement on the method based on Shannon sampling theory, which does not involve any multiple integration and provides higher order estimates of the eigenvalues at a very low cost. A few examples shall be presented to illustrate the power of the method and a comparison made with the the exact eigenvalues obtained as squares of the zeros of the exact characteristic functions.
988.
Anatoliy Samoilenko Manuel Pinto Sergei Trofimchuk 《Proceedings of the American Mathematical Society》2005,133(1):145-154
We apply the Krylov and Bogolyubov asymptotic integration procedure to asymptotically autonomous systems. First, we consider linear systems with quasi-periodic coefficient matrix multiplied by a scalar factor vanishing at infinity. Next, we study the asymptotically autonomous Van-der-Pol oscillator.
989.
Igor Rivin 《Proceedings of the American Mathematical Society》2005,133(5):1299-1305
We define a class of multivariate Laurent polynomials closely related to Chebyshev polynomials and prove the simple but somewhat surprising (in view of the fact that the signs of the coefficients of the Chebyshev polynomials themselves alternate) result that their coefficients are non-negative. As a corollary we find that and are positive definite functions. We further show that a Central Limit Theorem holds for the coefficients of our polynomials.
990.
Ergodic isospectral theory of the Lax pairs of Euler equations with harmonic analysis flavor 总被引:2,自引:0,他引:2
Y. Charles Li 《Proceedings of the American Mathematical Society》2005,133(9):2681-2687
Isospectral theory of the Lax pairs of both 3D and 2D Euler equations of inviscid fluids is developed. Eigenfunctions are represented through an ergodic integral. The Koopman group and mean ergodic theorem are utilized. Further harmonic analysis results on the ergodic integral are introduced. The ergodic integral is a limit of the oscillatory integral of the first kind.