全文获取类型
收费全文 | 507篇 |
免费 | 48篇 |
国内免费 | 14篇 |
专业分类
化学 | 31篇 |
力学 | 259篇 |
综合类 | 4篇 |
数学 | 61篇 |
物理学 | 214篇 |
出版年
2023年 | 5篇 |
2022年 | 5篇 |
2021年 | 8篇 |
2020年 | 11篇 |
2019年 | 6篇 |
2018年 | 6篇 |
2017年 | 10篇 |
2016年 | 14篇 |
2015年 | 9篇 |
2014年 | 21篇 |
2013年 | 21篇 |
2012年 | 15篇 |
2011年 | 33篇 |
2010年 | 22篇 |
2009年 | 13篇 |
2008年 | 21篇 |
2007年 | 26篇 |
2006年 | 37篇 |
2005年 | 31篇 |
2004年 | 31篇 |
2003年 | 20篇 |
2002年 | 24篇 |
2001年 | 14篇 |
2000年 | 20篇 |
1999年 | 12篇 |
1998年 | 12篇 |
1997年 | 12篇 |
1996年 | 10篇 |
1995年 | 17篇 |
1994年 | 8篇 |
1993年 | 17篇 |
1992年 | 7篇 |
1991年 | 16篇 |
1990年 | 18篇 |
1989年 | 5篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有569条查询结果,搜索用时 15 毫秒
31.
32.
Achamma Kurian C V Bindhu S S Harilal Riju C Issac V P N Nampoori C P G Vallabhan 《Pramana》1994,43(5):401-406
A simple method based on laser beam deflection to study the variation of diffusion coefficient with concentration in a solution
is presented. When a properly fanned out laser beam is passed through a rectangular cell filled with solution having concentration
gradient, the emergent beam traces out a curved pattern on a screen. By taking measurements on the pattern at different concentrations,
the variation of diffusion coefficient with concentration can be determined. 相似文献
33.
34.
35.
戴世强 《应用数学和力学(英文版)》1991,12(7):617-625
In this paper,we reexamine the method of successive approximation presented byProf.Chien Wei-zang for solving the problem of large deflection of a circular plate,and findthat the method could be regarded as the method of strained parameters in the singularperturbation theory.In terms of the parameter representing the ratio of the centerdeflection to the thickness of the plate,we make the asymptotic expansions of thedeflection,membrane stress and the parameter of load as in Ref.[1],and then give theorthogonality conditions(i.e.the solvability conditions)for the resulting equations,bywhich the stiffness characteristics of the plate could be determined.It is pointed out thatwith the solutions for the small deflection problem of the circular plate and theorthogonality conditions,we can derive the third order approximate relations between theparameter of load and the center deflection and the first-term approximation of membranestresses at the center and edge of the plate without solving the differential equ 相似文献
36.
Samir AL-Sadder Raid A. Othman AL-Rawi 《Archive of Applied Mechanics (Ingenieur Archiv)》2006,75(8-9):459-473
An efficient scheme, called quasi-linearization finite differences, is developed for large-deflection analysis of prismatic
and non-prismatic slender cantilever beams subjected to various types of continuous and discontinuous external variable distributed
and concentrated loads in horizontal and vertical global directions. Simultaneous equations of highly nonlinear and linear
terms are obtained when casting the derived exact highly nonlinear governing differential equation using central finite differences
on the nodes along the beam. A quasi-linearization scheme is used to solve these equations based on successive corrections
of the nonlinear terms in the simultaneous equations. The nonlinear terms in the simultaneous equations are assumed constant
during each correction (iteration). Several representative numerical examples of prismatic and non-prismatic slender cantilever
beams with different loading conditions are analyzed to illustrate the merits of the adopted numerical scheme as well as its
validity, accuracy and efficiency. The results of the present scheme are checked using large-displacement finite element analysis
by the MSC/NASTRAN program. A comparison between the present secheme, MSC/NASTRAN and available results from the literature
reveals excellent agreement. The advantage of the new scheme is that the load can be applied in one step with few iterations
(3–6 iterations). 相似文献
37.
38.
ANALYTICAL EVALUATION OF PERMANENT DEFLECTION OF A THIN CIRCULAR PLATE STRUCK NORMALLY AT ITS CENTER BY A PROJECTILE 总被引:1,自引:0,他引:1
Chen Liebin Yang Jialing 《Acta Mechanica Solida Sinica》2007,20(2):117-122
The permanent deflection of a thin circular plate struck normally at its center by a projectile is studied by an approximate theoretical analysis,FEM simulation and experiment.The plate made of rate sensitive and strain-hardening material undergoes serious local deformation but is not perforated during the impact.The theoretical analysis is based on an energy approach, in which the Cowper-Symonds equation is used for the consideration of strain rate sensitive effects and the parameters involved are determined with the aid of experimental data.The maximum permanent deflections predicted by the theoretical model are compared with those of FEM sim- ulation and published papers obtained both by theory and experiment,and good agreement is achieved for a wide range of thickness of the plates and initial impact velocities. 相似文献
39.
40.
An extension of the Elastica theory is developed to study the large deflection of an elastic-perfectly plastic horizontal
cantilever beam subjected to a vertical concentrated force at its tip. The entire process is divided into four stages: I.elastic
in the whole cantilever; II.loading and developing of the plastic region; III.unloading in the plastic region; and IV.reverse
loading. Solutions for stages I and II are presented in a closed form. A combination of closed-form solution and numerical
integration is presented for stage III. Finally, stage IV is qualitatively studied. Computed results are given and compared
with those from small-deflection theory and from the Elastica theory. 相似文献