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71.
72.
M. Cvetič-Krivec B. Golli N. Mankoč-Borštnik M. Rosina 《Physics letters. [Part B]》1981,99(6):486-488
The nonstrange resonances which cannot decay in the NN, NΔ or ΔΔ channels or which can decay in these channels only with the and tensor quark-quark interaction, are presented in the nonrelativistiv quark model with six quarks grouped in two clusters. The GCM calculation gives energies of 3203 MeV, 2540 MeV and 2814 MeV for the resonances (T = 0, S = 0, L = 0), (T = 0, S = 1, L = 1) and (T = 1, S = 0, L = 1), respectively. 相似文献
73.
F.D. Becchetti P.R. Christensen V.I. Manko R.J. Nickles 《Physics letters. [Part B]》1973,43(4):279-283
The spectroscopic factors deduced from a finite-range DWBA analysis of the (16O, 15N) reaction show systematic discrepancies with those obtained from (τ,d), and (α,t) and (d,n) reactions depending on whether or . The results depend sensitively on the selection rules used, however. 相似文献
74.
Norma Susana Mankoč Mankoč Borštnik 《International Journal of Theoretical Physics》2001,40(1):315-338
Polynomials in Grassmann algebra can be used to describe the internal degrees, spins and charges of spinors, scalars, and vectors. It was shown by Manko Bortnik and Nielsen that Kähler spinors can be generalized to describe spins of vectors as well as spins and charges of scalars, vectors, and spinors. In dimensions 14 and higher, the spontaneous breaking of symmetry leads gravity in d dimensions to manifest in 4-dimensional subspace as ordinary gravity and all needed gauge fields as well as the Yukawa couplings. Both approaches, Kähler's one (if generalized) and ours, manifest four generations of massless fermions, which are left-handed SU(2) doublets and right-handed SU(2) singlets. A possible way of spontaneously breaking symmetries is pointed out at the level of canonical momentum. 相似文献
75.
Synthesis and characterization of mesoporous indium tin oxide possessing an electronically conductive framework 总被引:2,自引:0,他引:2
The new mesoporous transparent conducting oxide based on indium-tin-oxide, meso-ITO, has been synthesized by a modified sol-gel method, using CTAB as the surfactant. Critical was the employment of triethanolamine to control the rate of hydrolysis and inhibit deposition of the bulk oxides. Removal of the surfactant by calcination yielded a relatively well-ordered worm-hole motif arrangement of pores visible in the TEM and stable to 400 degrees C. BET measurements revealed no hysteresis in the absorption-desorption isotherm, consistent with a narrow pore-size distribution (between 20 and 40 A depending on the In:Sn ratio); surface areas ranged between 270 and 310 m2/g. This colorless material is the first mesoporous oxide exhibiting substantial framework conductivity, with a conductivity at 25 degrees C of 1.2 x 10-3 S/cm. This distinguishes it from mesoporous mixed-valence transition-metal oxides that exhibit weak hopping semiconductor behavior and much lower conductivity. 相似文献
76.
77.
This paper considers the extended classical Blasius and Sakiadis equations, by considering a uniform free stream parallel
to a fixed or moving flat plate, which has more practical significance. It is assumed that the plate is subjected to a constant
heat flux, and moves in the same or opposite direction to the free stream. The resulting system of nonlinear ordinary differential
equations is solved numerically using a finite-difference method. Numerical results are obtained for the skin friction coefficient
and the local Nusselt number as well as the velocity and temperature profiles for some values of the governing parameters,
namely the velocity ratio parameter and the Prandtl number. The results indicate that dual solutions exist when the plate
and the free stream move in the opposite directions. 相似文献
78.
79.
In this paper, the unsteady three‐dimensional boundary layer flow due to a stretching surface in a viscous and incompressible micropolar fluid is considered. The partial differential equations governing the unsteady laminar boundary layer flow are solved numerically using an implicit finite‐difference scheme. The numerical solutions are obtained which are uniformly valid for all dimensionless time from initial unsteady‐state flow to final steady‐state flow in the whole spatial region. The equations for the initial unsteady‐state flow are also solved analytically. It is found that there is a smooth transition from the small‐time solution to the large‐time solution. The features of the flow for different values of the governing parameters are analyzed and discussed. The solutions of interest for the skin friction coefficient with various values of the stretching parameter c and material parameter K are presented. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
80.
The induced unsteady flow due to a stretching surface in a rotating fluid, where the unsteadiness is caused by the suddenly stretched surface is studied in this paper. After a similarity transformation, the unsteady Navier–Stokes equations have been solved numerically using the Keller-box method. Also, the perturbation solution for small times as well as the asymptotic solution for large times, when the flow becomes steady, has been obtained. It is found that there is a smooth transition from the small time solution to the large time or steady state solution. 相似文献