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41.
42.
The magnetic susceptibility and Knight shift of the intermetallic compounds NdCu4 and NdCu5 were investigated over the temperature range 80–850 K. The most important contributions to the magnetic susceptibility are the Curie-Weiss term, expressing the paramagnetism of the localized 4?-electrons, and a temperature independent term, both of which have been determined. The phenomenological quantity Js? between the 4?-electron and conduction electron spins was found to be ?2.46.10?3eV for NdCu4 and 1.35.10?3 eV for NdCu5. A reversal in the sign of the s-? coupling for CeCu5 was noted.  相似文献   
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44.
Penrose showed in [6] that for every complex rectangular matrix aMnxm() there exists a unique bMnxm(), the generalized inverse of a, satisfying the following four conditions: i) a a*b=a, ii) b a*a=a, iii) b b*a=b, iv) a b*b=b.These condition can be expressed in terms of the triple product  相似文献   
45.
Compacton propagation under dissipation shows amplitude damping and the generation of tails. The numerical simulation of compactons by means of dissipative schemes also show the same behaviors. The truncation error terms of a numerical method can be considered as a perturbation of the original partial differential equation and perturbation methods can be applied to its analysis. For dissipative schemes, or when artificial dissipation is added, the adiabatic perturbation method yields evolution equations for the amplitude loss in the numerical solution and the amplitude of the numerically-induced tails. In this paper, such methods are applied to the K(2,2)K(2,2) Rosenau–Hyman equation, showing a very good agreement between perturbative and numerical results.  相似文献   
46.
The electron excitation of nucleon resonances is discussed both from the theoretical and from the experimental point of view. This discussion is based on a phenomenological approach that employs the conservation of the electromagnetic and vector-meson hadronic currents and the requirements of limiting chiral invariance. For the electron excitation of Jπ=1/2±,3/2±,5/2±,... nucleon resonances, the structure functions are defined in terms of Sachs transition form factors. The resulting resonance structure functions for l+Nl+R processes are used in parametrizing smooth (background) structure functions for l+Nl+X inelastic scattering.  相似文献   
47.

When an epidemic spreads into a population, it is often impractical or impossible to continuously monitor all subjects involved. As an alternative, we propose using algorithmic solutions that can infer the state of the whole population from a limited number of measures. We analyze the capability of deep neural networks to solve this challenging task. We base our proposed architecture on Graph Convolutional Neural Networks. As such, it can reason on the effect of the underlying social network structure, which is recognized as the main component in spreading an epidemic. The proposed architecture can reconstruct the entire state with accuracy above 70%, as proven by two scenarios modeled on the CoVid-19 pandemic. The first is a generic homogeneous population, and the second is a toy model of the Boston metropolitan area. Note that no retraining of the architecture is necessary when changing the model.

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48.
Uniform elements in algebraic lattices are studied and their relationship with some nonassociative extensions of Goldie's Second Theorem is shown.

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49.
The paper is concerned with a formal treatment of data structures. The introduction outlines the main features of Generalized Data Base Management Systems and gives the general diagram of information flow in such a system. Section 1 is concerned with the structuring of data on levels. For a given real object setB, the levels of data representation as item, record, and file are discussed and the structure of the levels is characterized. In section 2 a basic algorithm for file search is given. To characterize the file data structure, the concept of directory is defined. A conventional example closes this section. In section 3 the concepts of data base and subdata base are defined as next level of data organization, and the access algorithms to such data structures are described.  相似文献   
50.
Yeast particles (YPs) are 3–5 µm hollow and porous microspheres, a byproduct of some food grade yeast (Saccharomyces cerevisiae) extract manufacturing processes. Terpenes can be efficiently encapsulated inside YPs by passive diffusion through the porous cell walls. As previously published, this YP terpene encapsulation approach has been successfully implemented (1) to develop and commercialize fungicide and nematicide products for agricultural applications, (2) to co-load high potency agrochemical actives dissolved in terpenes or suitable solvents, and (3) to identify YP terpenes with broad-acting anthelmintic activity for potential pharmaceutical applications. These first-generation YP terpene materials were developed with a <2:1 terpene: YP weight ratio. Here we report methods to increase the terpene loading capacity in YPs up to 5:1 terpene: YP weight ratio. Hyper-loaded YP terpenes extend the kinetics of payload release up to three-fold compared to the commercialized YP terpene formulations. Hyper-loaded YP-terpene compositions were further optimized to achieve high terpene storage encapsulation stability from −20 °C to 54 °C. The development of hyper-loaded YP terpenes has a wide range of potential agricultural and pharmaceutical applications with terpenes and other compatible active substances that could benefit from a delivery system with a high payload loading capacity combined with increased payload stability and sustained release properties.  相似文献   
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