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51.
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Freeman J. Dyson 《Communications in Mathematical Physics》1970,19(3):235-250
Exact analytical expressions are found for the joint probability distribution functions ofn eigenvalues belonging to a random Hermitian matrix of orderN, wheren is any integer andN. The distribution functions, like those obtained earlier forn=2, involve only trigonometrical functions of the eigenvalue differences. 相似文献
53.
This paper contributes to the literature on the problem of allocation of resources to a set of risky investments. Our objective is to develop the ideas in the context of a research and development laboratory. A mathematical programming approach to the resource allocation problem is taken, and various forms for an objective function under risk are discussed. A probabilistic objective function appropriate to R & D is isolated and tested on a small hypothetical example. Parametric linear programming is used to yield a near-optimum allocation. 相似文献
54.
T.J. Watson-Yang B.N. Harmon A.J. Freeman 《Journal of magnetism and magnetic materials》1976,2(4):334-344
The magnetic field induced magnetization density and neutron magnetic form factor of Pd metal is obtained from an abinitio APW energy band study of its electronic structure and properties. The magnetization consists of the spin density calculated for states on the Fermi surface and a much smaller orbital contribution. The solid state wavefunctions are found to yield a spatial localization of the spin density which is greater than that of the very contracted Hartree-Fock density of the free Pd2+ ion. The theretical magnetic form factor, which is dominated by the contribution of the fifth band, is found to be in excellent agreement with the measurements of Cable, Wollan, Felcher, Brun and Hornfeldt. 相似文献
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Low temperature 1H NMR and 13C NMR, and IR suggest that the -chloroperbenzoic acid (MCPBA) oxidation of neopentyl neopentanethiolsulfinate leads to the formation of (E)- and (Z)-2,2-dimethylpropanethial S-oxide, neopentyl neopentanethiolsulfonate, and other products. 相似文献
58.
Chad?A?Dickey Marcia?N?Gordon Donna?M?Wilcock Donna?L?Herber Melissa?J?Freeman Dave?MorganEmail author 《BMC neuroscience》2005,6(1):7
Background
The pathology of Alzheimer's disease (AD) is comprised of extracellular amyloid plaques, intracellular tau tangles, dystrophic neurites and neurodegeneration. The mechanisms by which these various pathological features arise are under intense investigation. Here, expanding upon pilot gene expression studies, we have further analyzed the relationship between Na+/K+ ATPase and amyloid using APP+PS1 transgenic mice, a model that develops amyloid plaques and memory deficits in the absence of tangle formation and neuronal or synaptic loss. 相似文献59.
Valiente-Dobón JJ Steinhardt T Svensson CE Afanasjev AV Ragnarsson I Andreoiu C Austin RA Carpenter MP Dashdorj D de Angelis G Dönau F Eberth J Farnea E Freeman SJ Gadea A Garrett PE Görgen A Grinyer GF Hyland B Jenkins D Johnston-Theasby F Joshi P Jungclaus A Lieb KP Macchiavelli AO Moore EF Mukherjee G Napoli DR Phillips AA Plettner C Reviol W Sarantites D Schnare H Schumaker MA Schwengner R Seweryniak D Smith MB Stefanescu I Thelen O Wadsworth R 《Physical review letters》2005,95(23):232501
Three rotational bands in 74Kr were studied up to (in one case one transition short of) the maximum spin I(max) of their respective single-particle configurations. Their lifetimes have been determined using the Doppler-shift attenuation method. The deduced transition quadrupole moments reveal a modest decrease, but far from a complete loss of collectivity at the maximum spin I(max). This feature, together with the results of mean field calculations, indicates that the observed bands do not terminate at I = I(max). 相似文献
60.