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141.
142.
143.
Donald Richards 《Statistics & probability letters》1983,1(3):141-145
Recent articles by Kushner and Meisner (1980) and Kushner, Lebow and Meisner (1981) have posed the problem of characterising the ‘EP’ functions f(S) for which Ef(S) for which E(f(S)) = λnf(Σ) for some λn ? , whenever the m × m matrix S has the Wishart distribution W(m, n, Σ). In this article we obtain integral representations for all nonnegative EP functions. It is also shown that any bounded EP function is harmonic, and that EP polynomials may be used to approximate the functions in certain Lp spaces. 相似文献
144.
Robert T. Parfitt David E. Games Ronald F. Cookson Alan C. Richards Norman Lynaugh 《Journal of mass spectrometry : JMS》1978,13(6):341-343
A combination of electron impact, chemical ionization, field desorption and field ionization mass spectrometry has been employed to demonstrate that the LAH reduction product of 3H-1,2-benzodithiole-3-thione is the dimer, dibenzo[c,h]-3H,10H-dihydro-1,2,8,9-tetrathiecine. 相似文献
145.
Comparisons are made between various finite difference algorithms used for the numerical solution of two-dimensional viscous flow. Central difference algorithms recently developed by the authors are compared with the well established upwind difference algorithms. Some analytical solutions to the Navier-Stokes equations have been produced in order for meaningful comparisons to be made. On the basis of the results, the new central difference algorithms are recommended as being more accurate whilst requiring little additional computational effort. There is an upper limit on the grid Reynolds number for which these new methods will converge, but this will usually be when the flow would in practice be turbulent. 相似文献
146.
The near field of helium-air jets exhausting into an air environment has been experimentally investigated using an aspiration probe and flow visualization. Jets with varying density ratios and Reynolds numbers were studied. Pure helium jets with density ratios of 0.14 were found to display a self-excited behavior characterized by intense mixing. The centerline concentration decay was found to be substantially increased for the self-excited jet. Flow visualization revealed the expulsion of side jets from the potential core region of low density jets. Radial profiles of concentration provide additional evidence that side-jets produce vigorous mixing. 相似文献
147.
Palladium (II) catalyzed cleavage of phenyl-antimony and phenyl-phosphorus groups of Ph3Sb and Ph3P under carbon-dioxide or CO/NO atmosphere leading to benzoic acid, has been demonstrated. 相似文献
148.
A. Rembaum M. Chang G. Richards M. Li 《Journal of polymer science. Part A, Polymer chemistry》1984,22(3):609-621
The kinetics of the formation of polyacrolein microspheres by ionizing radiation (polymer I) were investigated. Their structure and reactivity were compared with polyacrolein microspheres prepared by base catalysis (polymer II). The study of Fourier infrared (IR) spectra of polymers I and II showed structural differences. The reaction of polyacrolein spheres with m-aminophenol indicated the presence of conjugated groups. The reaction of antibodies with polyacrolein spheres was investigated as a function of pH and the number of reactive aldehyde groups was determined by nitrogen analysis of polyacrolein-hydroxylamine adducts. Intensely fluorescent polyacrolein microspheres obtained by Co-γ-irradiation in sizes of 100 Å–4 μm have already found applications as immunoreagents for cell labeling and separation. 相似文献
149.
A simple combination of quantum mechanical and classical methods appears to lead to a new method for theoretical conformational analysis. 相似文献
150.