全文获取类型
收费全文 | 17097篇 |
免费 | 409篇 |
国内免费 | 220篇 |
专业分类
化学 | 1585篇 |
晶体学 | 71篇 |
力学 | 154篇 |
综合类 | 19篇 |
数学 | 14628篇 |
物理学 | 1269篇 |
出版年
2023年 | 49篇 |
2022年 | 53篇 |
2021年 | 69篇 |
2020年 | 93篇 |
2019年 | 407篇 |
2018年 | 432篇 |
2017年 | 235篇 |
2016年 | 184篇 |
2015年 | 210篇 |
2014年 | 483篇 |
2013年 | 920篇 |
2012年 | 558篇 |
2011年 | 1023篇 |
2010年 | 842篇 |
2009年 | 1136篇 |
2008年 | 1182篇 |
2007年 | 1249篇 |
2006年 | 921篇 |
2005年 | 655篇 |
2004年 | 516篇 |
2003年 | 467篇 |
2002年 | 401篇 |
2001年 | 353篇 |
2000年 | 333篇 |
1999年 | 418篇 |
1998年 | 404篇 |
1997年 | 320篇 |
1996年 | 373篇 |
1995年 | 417篇 |
1994年 | 389篇 |
1993年 | 330篇 |
1992年 | 305篇 |
1991年 | 188篇 |
1990年 | 197篇 |
1989年 | 194篇 |
1988年 | 126篇 |
1987年 | 121篇 |
1986年 | 115篇 |
1985年 | 146篇 |
1984年 | 149篇 |
1983年 | 89篇 |
1982年 | 146篇 |
1981年 | 104篇 |
1980年 | 98篇 |
1979年 | 74篇 |
1978年 | 91篇 |
1977年 | 59篇 |
1976年 | 55篇 |
1975年 | 14篇 |
1974年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
51.
52.
We shall give a direct proof of the independence result of a Buchholz style-Hydra Game on labeled finite trees. We shall
show that Takeuti-Arai's cut-elimination procedure of and of the iterated inductive definition systems can be directly expressed by the reduction rules of Buchholz's Hydra Game.
As a direct corollary the independence result of the Hydra Game follows.
Received: August 23, 1994 / Revised: July 24, 1995 and May 9, 1996 相似文献
53.
Modifying complex plane rotations, we derive a new Jacobi-type algorithm for the Hermitian eigendecomposition, which uses only real arithmetic. When the fast-scaled rotations are incorporated, the new algorithm brings a substantial reduction in computational costs. The new method has the same convergence properties and parallelism as the symmetric Jacobi algorithm. Computational test results show that it produces accurate eigenvalues and eigenvectors and achieves great reduction in computational time.The work of this author was supported in part by the National Science Foundation grant CCR-8813493 and by the University of Minnesota Army High Performance Computing Research Center contract DAAL 03-89-C-0038.The work of this author was supported in part by the University of Minnesota Army High Performance Computing Research Center contract DAAL 03-89-C-0038. 相似文献
54.
Summary. We study a diffusion model of an interacting particles system with general drift and diffusion coefficients, and electrostatic
inter-particles repulsion. More precisely, the finite particle system is shown to be well defined thanks to recent results
on multivalued stochastic differential equations (see [2]), and then we consider the behaviour of this system when the number
of particles goes to infinity (through the empirical measure process). In the particular case of affine drift and constant diffusion coefficient,
we prove that a limiting measure-valued process exists and is the unique solution of a deterministic PDE. Our treatment of
the convergence problem (as ) is partly similar to that of T. Chan [3] and L.C.G. Rogers - Z. Shi [5], except we consider here a more general case allowing
collisions between particles, which leads to a second-order limiting PDE.
Received: 5 August 1996 / In revised form: 17 October 1996 相似文献
55.
Dorina Mitrea Marius Mitrea Jill Pipher 《Journal of Fourier Analysis and Applications》1997,3(2):131-192
We study boundary value problems for the time-harmonic form of the Maxwell equations, as well as for other related systems
of equations, on arbitrary Lipschitz domains in the three-dimensional Euclidean space. The main goal is to develop the corresponding
theory for Lp-integrable bounday data for optimal values of p's. We also discuss a number of relevant applications in electromagnetic scattering. 相似文献
56.
Guido Cortesani 《Annali dell'Universita di Ferrara》1997,43(1):27-49
Let Ω be an open and bounded subset ofR
n
with locally Lipschitz boundary. We prove that the functionsv∈SBV(Ω,R
m
) whose jump setS
vis essentially closed and polyhedral and which are of classW
k, ∞ (S
v,R
m) for every integerk are strongly dense inGSBV
p(Ω,R
m
), in the sense that every functionu inGSBV
p(Ω,R
m
) is approximated inL
p(Ω,R
m
) by a sequence of functions {v
k{j∈N with the described regularity such that the approximate gradients ∇v
jconverge inL
p(Ω,R
nm
) to the approximate gradient ∇u and the (n−1)-dimensional measure of the jump setsS
v
j converges to the (n−1)-dimensional measure ofS
u. The structure ofS
v can be further improved in casep≤2.
Sunto Sia Ω un aperto limitato diR n con frontiera localmente Lipschitziana. In questo lavoro si dimostra che le funzioniv∈SBV(Ω,R m ) con insieme di saltoS v essenzialmente chiuso e poliedrale che sono di classeW k, ∞ (S v,R m ) per ogni interok sono fortemente dense inGSBV p(Ω,R m ), nel senso che ogni funzioneu∈GSBV p(Ω,R m ) è approssimata inL p(Ω,R m ) da una successione di funzioni {v j}j∈N con la regolaritá descritta tali che i gradienti approssimati ∇v jconvergono inL p(Ω,R nm ) al gradiente approssimato ∇u e la misura (n−1)-dimensionale degli insiemi di saltoS v jconverge alla misura (n−1)-dimensionale diS u. La struttura diS vpuó essere migliorata nel caso in cuip≤2.相似文献
57.
58.
Summary. We present a simple proof, based on modified logarithmic Sobolev inequalities, of Talagrand’s concentration inequality for
the exponential distribution. We actually observe that every measure satisfying a Poincaré inequality shares the same concentration
phenomenon. We also discuss exponential integrability under Poincaré inequalities and its consequence to sharp diameter upper
bounds on spectral gaps.
Received: 10 June 1996 / In revised form: 9 August 1996 相似文献
59.
Kevin Houston 《Inventiones Mathematicae》2002,147(3):471-485
The disentanglement of certain augmentations is shown to be the topological join of a disentanglement and a Milnor fibre.
The kth disentanglement of a finite map is defined and for corank 1 maps from ℂ
n
to ℂ
n
+1 it is shown that they are homotopically equivalent to a wedge of spheres. Applications to the Mond conjecture are given.
Oblatum 24-VII-2000 & 5-VII-2001?Published online: 12 October 2001 相似文献
60.