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排序方式: 共有404条查询结果,搜索用时 15 毫秒
1.
The zero dissipation limit of the one-dimensional non-isentropic micropolar equations is studied in this paper. If the given rarefaction wave which connects to vacuum at one side, a sequence of solution to the micropolar equations can be constructed which converge to the above rarefaction wave with vacuum as the viscosity and the heat conduction coefficient tend to zero. Moreover, the uniform convergence rate is obtained. The key point in our analysis is how to control the degeneracies in the vacuum region in the zero dissipation limit process. 相似文献
2.
A Generalization of Regular Left Acts 总被引:1,自引:0,他引:1
Liu Zhongkui 《东北数学》1997,(2)
AGeneralizationofRegularLeftActs*)LiuZhongkui(刘仲奎)(DepartmentofMathematics,NorthwestNormalUniversity,Lanzhou,730070)J.Ahsan(D... 相似文献
3.
Michael A. Zazanis 《Queueing Systems》1992,11(4):419-428
We examine level crossings of sample paths of queueing processes and investigate the conditions under which the limiting empirical distribution for the workload process exists and is absolutely continuous. The connection between the density of the workload distribution and the rate of downcrossings is established as a sample path result that does not depend on any stochastic assumptions. As a corollary, we obtain the sample path version of the Takács formula connecting the time and customer stationary distributions in a queue. Defective limiting empirical distributions are considered and an expression for the mass at infinity is derived.This research has been supported in part by NSF Grants ECS-8811003 and DDM-8905638. 相似文献
4.
介绍了函数的最大项展开式和CRM展开式及其图形表示,提出函数K图和dj图的零点的概念,并以此为基础讨论了基于零点的函数K图和dj图之间的转换方法。 相似文献
5.
用非水滴定法和Hammett系列指示剂测定了COS水解碱改性γ-Al_2O_3催化剂的表面碱强度分布.发现表面碱强度分布不均匀与表面能量分布不均匀相呼应.采用零点酸碱强度(H_(0,max))及碱中心区域分析法,Bronsted催化定律,进一步证实COS水解反应具有明显碱催化特征,较高活性催化剂的H_(0,max)一般为10左右,对COS水解反应起主要作用的碱性中心的碱强度(H_0)为4.8≤H_0≤9.8.对碱金属氧化物改性后的γ-Al_2O_3催化剂,Bronsted规律在每个碱强度分区域内是适用的. 相似文献
6.
Summary Electrophoretic mobility measurements in the pH 2‐10 range are described for several commercial HPLC silica microparticles
and a laboratory-produced product. The content of metal impurities for the silicas was also determined by AAS. An acidic/hydrothermal
treatment was used to generate a more homogenous surface for some of the silicas. The zero points of charge (zpc) for both
a native and a treated silica plus several commercial HPLC silicas were compared. The electrophoretic mobility method may
be useful in predicting the utility of certain types of silica supports for chromatographic separations. 相似文献
7.
George A. Hagedorn 《Theoretical chemistry accounts》1990,77(3):163-190
Summary We summarize the results of a mathematical study of the time-dependent Born-Oppenheimer approximation near crossings of two non-degenerate electron energy surfaces. We illustrate our techniques by relatively simple examples that contain the essential ingredients of the general cases. We discuss all generic types of crossings of two non-degenerate electron energy surfaces.Supported in part by the National Science Foundation under Grant number DMS-8801360 相似文献
8.
Enn?LustEmail author Alar?J?nes Tanel?P?rn Priit?Nigu 《Journal of Solid State Electrochemistry》2004,8(4):224-237
Electrochemical characteristics for the nanoporous carbon|Et4NBF4+acetonitrile interface have been studied by cyclic voltammetry and impedance spectroscopy methods. The influence of the electrolyte concentration and thickness of the nanoporous electrode material on the shape of the cyclic voltammetry and impedance curves has been established and the reasons for these phenomena are discussed. A value of zero charge potential, depending slightly on the structure and concentration of the electrolyte, the region of ideal polarizability and other characteristics have been established. The nanoporous nature of the carbon electrodes introduces a distribution of resistive and capacitive elements, giving rise to complicated electrochemical behaviour. Analysis of the complex plane plots shows that the nanoporous carbon|Et4NBF4+acetonitrile electrolyte interface can be simulated by an equivalent circuit, in which two parallel conduction paths in the solid and liquid phases are interconnected by the double-layer capacitance in parallel with the complex admittance of the hindered reaction of the charge transfer or of the partial charge transfer (i.e. adsorption stage limited) process. The values of the characteristic frequency depend on the electrolyte concentration and electrode potential, i.e. on the nature of the ions adsorbed at the surface of the nanoporous carbon electrode. The value of the solid state phase resistance established is independent of the thickness of the electrode material. 相似文献
9.
Ward Whitt 《Queueing Systems》1991,9(3):235-268
A fundamental principle of queueing theory isL=W (Little's law), which states that the time-average or expected time-stationary number of customers in a system is equal to the product of the arrival rate and the customer-average or expected customer-stationary time each customer spends in the system. This principle is now well known and frequently applied. However, in recent years there have been extensions, such as H=G and the continuous, distributional, ordinal and central-limit-theorem versions, which show that theL=W relation, when viewed properly, has much more power than was previously realized. Moreover, connections have been established between H=G and other fundamental relations, such as the rate conservation law and PASTA (Poisson arrivals see time averages), which show that there is a much greater unity in the overall theory than was previously realized. This paper provides a review.This paper is dedicated to the memory of our colleague Professor Peter Franken (1937–1989), who contributed greatly to the subject of this paper and to queueing theory more generally. 相似文献
10.
A novel electrochemical approach has been proposed to measure the interface potential at the electrode/solution interface based on reconstructing the three‐electrode system of a potentiostat. In this work, the method was investigated both theoretically and experimentally. Mathematical expressions, describing current? potential characteristics, were derived. Zero current potential Ezcp was defined as the potential at which the current is zero based on linear sweep voltammetry, and was determined from the I? E curve to measure the interface potential. The experimental results obtained with the couples Fe(CN)63?/Fe(CN)64? and Co(NH3)63+/Co(NH3)62+ as examples agreed well with the theory. The proposed approach exhibits an excellent performance for measuring the interface potential due to the advantages of rapidity, high stability and accuracy. 相似文献