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排序方式: 共有261条查询结果,搜索用时 15 毫秒
71.
J. D. Pandey Siddharth Pandey Shikha Gupta A. K. Shukla 《Journal of solution chemistry》1994,23(9):1049-1059
Viscosities of ternary liquid mixtures containing benzene + cyclohexane + carbon tetrachloride and the three possible binary combinations were measured at 25°C, and the excess viscosities were computed. Theoretical expressions for viscosity were developed on the basis of the Flory theory, the significant structure theory and a theory based on a method of estimating the properties of multi-component systems from those of binary systems. Reasonable agreement between experimental and theoretical viscosities is found. 相似文献
72.
Ugur Yahsi 《Journal of Polymer Science.Polymer Physics》1999,37(9):879-887
A new model for zero‐shear viscosity, η, is proposed. The model combines the Simha–Somcynsky (SS) statistical thermodynamic theory of liquids with the Eyring Significant Structure (ESS) transport theory. Using the new model, a successful linearization of the experimental viscosity vs. hole fraction data was obtained. A comparison between the new model and Utracki's relation, ln η = a0 + a1/(h + a2) was also made. The former was found to be more successful for both linear and nonlinear structures, provided that an appropriate choice of the degrees of freedom of normal and activated states was made. The proportionality constant of the activation energy and transmission coefficient were also calculated for each species. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 879–887, 1999 相似文献
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指出现行大学物理实验教材中有效数字的概念存在不足之处,提出在大学物理实验教学中有效数字的新解释:任何测量值都是有效数字,所有的有效数字都包含有准确值和存疑值,有效数字的位数由有效位数来确定。 相似文献
76.
This paper investigates variability in the occurrence of different event sequences on an annual basis during the operation of a proposed nuclear facility. During the operational period of a nuclear facility, the annual radiological dose received by workers or members of the public depends on the number of event sequence occurrences. Based on the facility design, some combinations of event sequences will be expected to occur at least once during the operational period, and some combinations will not. This paper provides analytical solutions for calculating the expected number of combinations of independent event sequences. These analytical solutions agree with numerical solutions for an example problem. Although uncertainties can be incorporated into the method, only point-estimate parameter values are used in the example problem presented. The main objectives of this paper are to present calculational approaches to (i) identify which combinations of event sequences within the same year are expected to occur at least once during the operational life of a proposed facility and (ii) determine the annual doses from those identified combinations. Facility performance based on some proposed design is evaluated against the operational dose limits. Because the operational dose limits tend to be annual quantities that may not be exceeded in any year of operation, calculation of the doses resulting from combinations of event sequences that are expected to occur at least once can provide insight on the maximum annual dose expected during the operation of a proposed facility. 相似文献
77.
The scattering and absorption differential cross sections for nonlinear QED process such as double photon Compton scattering
have been measured as a function of independent final photon energy. The incident gamma photons are of 0.662 MeV in energy
as produced by an 8 Ci137Cs radioactive source and thin aluminum foils are used as scatterer. The two simultaneously emitted photons in this process
are detected in coincidence using two Nal(T1) scintillation detectors and a slow-fast coincidence set-up of 30 nsec resolving
time. The measured values of scattering and absorption differential cross sections agree with theory within experimental estimated
error. 相似文献
78.
Bursty events and incremental diffusion in a local diffusion and multi—scale convection system
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A one-dimensional cellular automaton is defined without the critical gradient rule (Δh>Δh_c) which is essential to the existence of avalanches in self-organized criticality (SOC) models. Instead, only the local diffusion rule is used, however, the characteristics of SOC, such as the bursty behaviour, power-law decay in fluctuation spectra, self-similarity over a broad range of scales and long-time correlations, are still observed in these numerical experiments. This numerical model is established to suggest that the bursty events and the incremental diffusion observed universally in fusion experiments do not necessarily imply the submarginal dynamics. 相似文献
79.
Richard A. Becker Linda A. Clark Diane Lambert 《Journal of computational and graphical statistics》2013,22(3):277-283
Abstract Cave plots are a good way to compare data from two or more time series, even if the two series are observed at irregular times. Cave plots can show thousands of measurements, but they are readily understood, preserve individual values, highlight short-term, long-term, and periodic fluctuations, and make correlation (or lack of correlation) between two time series apparent. We have used a page of cave plots to show millions of measurements on network reliability and tens of thousands of measurements on air quality. The plots highlight features of the data that warrant a closer look. 相似文献
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