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41.
In this paper,we research general Defective Cion Problem under the model S,i.e,the number d of Defective cions is not fixed. For d=O,1,or 2. we get some good results. 相似文献
42.
基于粗糙集理论的知识约简及应用实例 总被引:5,自引:0,他引:5
在保持分类能力不变的前提下 ,通过利用粗糙集理论中的知识约简方法 ,在保护知识库分类不变的条件下 ,删除其中不相关或不重要的知识 ,从而导出问题的决策 .利用基于决策表的粗糙集模型算法 ,实例分析如何数字化表示决策表 ,并对其进行属性约简和属性值的约简 ,从而提取决策规则 . 相似文献
43.
S. Yu. Podzorov 《Algebra and Logic》2003,42(2):121-129
S. Goncharov and S. Badaev showed that for
, there exist infinite families whose Rogers semilattices contain ideals without minimal elements. In this connection, the question was posed as to whether there are examples of families that lack this property. We answer this question in the negative. It is proved that independently of a family chosen, the class of semilattices that are principal ideals of the Rogers semilattice of that family is rather wide: it includes both a factor lattice of the lattice of recursively enumerable sets modulo finite sets and a family of initial segments in the semilattice of
-degrees generated by immune sets. 相似文献
44.
We introduce a class of set-functions on the set of natural numbers, which are called super-measures. Super-measures are then
utilized to characterize a certain class of topological measures (previously called quasi-measures, see below) which arises
naturally. The members of this class of topological measures are called finitely defined, and are shown to be dense in the
set of all topological measures.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
45.
A -frame is a lattice in which countable joins exist and binary meets distribute over countable joins. In this paper, the category MFrm, of metric -frames, is introduced, and it is shown to be equivalent to the category MLFrm
u, of metric Lindelöf frames.Finally, it is shown that the complete metric -frames are exactly the cozero parts of complete metric Lindelöf frames. 相似文献
46.
胡迪鹤 《数学物理学报(B辑英文版)》2003,23(2)
The structure of any a.s. self-similar set K(w) generated by a class of random elements {gn,wσ} taking values in the space of contractive operators is given and the approximation of K(w) by the fixed points {Pn,wσ} of {gn,ow} is obtained. It is useful to generate the fractal in computer. 相似文献
47.
Rafael O. Ruggiero Vladimir A. Rosas Meneses 《Bulletin of the Brazilian Mathematical Society》2003,34(2):263-274
In this paper, we show that the Pesin set of an expansive
geodesic flow in compact manifold with no conjugate points and
bounded asymptote coincides a.e with an open and dense set of
the unit tangent bundle. We also show that the set of hyperbolic
periodic orbits is dense in the unit tangent bundle. 相似文献
48.
The second part of this paper deals with the systolic implementation of the computational kernel for factorial data analysis, defined in Part I, on special-purpose hardware. The framework of the study is that a sequence of different algorithms has to be performed on a unique hardware array. This fact has led us to the design of the programmable systolic array SARDA: this is a triangular array which consists of programmable nodes with local memory and programmable orthogonal connections. 相似文献
49.
为实时恢复天文或空间目标的湍流退化成像,提出一种适应大气湍流动态变化的多通道自适应光学图像恢复方法.以自适应光学校正后不同时刻的目标成像作为多个通道,建立求解系统点扩散函数的线性方程,根据解出的点扩散函数利用超拉普拉斯算法,求解待观测目标的估计值.结果表明:不同时刻的点扩散函数之间存在互质关系,满足多通道盲识别的理论要求.利用建立的线性方程求解出的点扩散函数与原点扩散函数的均方误差在10^-30~10^-27量级,采用超拉普拉斯算法恢复出的目标成像与原始目标之间的均方误差在10^-5~10^-4量级.本文研究为湍流退化图像的实时恢复提供了理论基础. 相似文献
50.
An implantation terminal for the preparation of p-n junction particle detectors was set up on a multipurpose isotope separator. To provide for homogeneous implantation. the ion beam is swept in the horizontal direction and the samples are moved vertically. In order to be able to implant samples with different geometry two different sample moving systems can be mounted in the implantation chamber. A rotating drum is used for round wafers. a rotating disc in connection with a rotating diaphragm is provided for very elongated samples. Implanted resistive layers on a wafer have resistances which differ by less than ±1 %. 相似文献