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51.
Clement W.H. Lam 《Discrete Mathematics》1983,43(1):65-78
A matrix C of order n is orthogonal if CCT=dI. In this paper, we restrict the study to orthogonal matrices with a constant m > 1 on the diagonal and ±1's off the diagonal. It is observed that all skew symmetric orthogonal matrices of this type are constructed from skew symmetric Hadamard matrices and vice versa. Some simple necessary conditions for the existence of non-skew orthogonal matrices are derived. Two basic construction techniques for non-skew orthogonal matrices are given. Several families of non-skew orthogonal matrices are constructed by applying the basic techniques to well-known combinatorial objects like balanced incomplete block designs. It is also shown that if m is even and n=0 (mod 4), then an orthogonal matrix must be skew symmetric. The structure of a non-skew orthogonal matrix in the special case of m odd,n=2 (mod 4) and m?1/6n is also studied in detail. Finally, a list of cases with n?50 is given where the existence of non-skew orthogonal matrices are unknown. 相似文献
52.
53.
54.
D.A. Bell J.A. Buchanan M.M. Calkin J.M. Clement W.H. Dragoset M. Furić K.A. Johns J.D. Lesikar H.E. Miettinen T.A. Mulera G.S. Mutchler G.C. Phillips J.B. Roberts S.E. Turpin 《Physics letters. [Part B]》1980,94(3):310-314
We have measured the asymmetry parameter A and the spin correlation parameter Ann in pp elastic scattering, using the Argonne ZGS polarized proton beam and a polarized proton target. Angular distributions of A and Ann for |t| ? 0.2 (GeV/c)2wereobtainedateightmomentabetween 1.10 and 2if2.75 GeV/c. We find significant structure in both the energy and t-dependence of Ann at these energies. At plab ≈ 1.34 GeV/cAnn reaches a very large value of about 0.8–0.9 near θcm = 90°. 相似文献
55.
56.
Previously derived sum rules are shown to have corrections if the potential contains a hard core. The corrections represent a total loss of single-particle strength which also occurs from the low-energy observable region in the soft-core case. Estimates give a reduction of at least 5 % in the total sum rules, but negligible additional spin-dependent corrections to the partial or spin-dependent sum rules. Important consequences of this lack of spin dependence are pointed out for existing and future sum-rule analyses of spectroscopic data. 相似文献
57.
We report a novel post‐growth microwave treatment approach to selectively modify the surface morphologies of gold (Au) films coated on the polystyrene (PS) bead substrates for effectively improving the surface‐enhanced Raman scattering (SERS) effect on the analytes. The discrete dipole approximation (DDA) model was introduced to evaluate the enhancement effects by calculating the localized electromagnetic field distribution and extinction efficiency based on the sizes of the trenches and voids, and the surface roughness of the modified Au–PS bead substrates. The SERS performance of microwave‐modified Au–PS substrates on rhodamine 6G (Rh 6G) and saliva yields at least 10‐fold improvements in SERS intensities compared to the as‐grown substrates, which is also in agreement with theoretical predictions by DDA modeling. This work demonstrates both experimentally and theoretically the efficacy of the microwave heating treatment on modifying the Au–PS bead substrates for the realization of high SERS performance in biomedical applications. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
58.
M. Abdel-Bary K. -Th. Brinkmann H. Clement E. Doroshkevich S. Dshemuchadse A. Erhardt W. Eyrich H. Freiesleben A. Gillitzer R. Jäkel L. Karsch K. Kilian E. Kuhlmann K. Möller H. P. Morsch L. Naumann N. Paul C. Pizzolotto J. Ritman E. Roderburg P. Schönmeier W. Schroeder M. Schulte-Wissermann G. Y. Sun A. Teufel A. Ucar G. J. Wagner M. Wagner P. Wintz P. Wüstner P. Zupranski 《The European Physical Journal A - Hadrons and Nuclei》2006,29(3):353-361
The reaction
has been studied in a kinematically complete experiment at a single beam momentum
GeV/c (T = 759MeV). All four ejectiles have been detected in the large-acceptance time-of-flight spectrometer COSY-TOF. We analyzed
the data along the lines of the spectator model as a means to isolate the quasi-free
reaction. The spectator proton was identified by its momentum and flight direction thus yielding access to the associated
Fermi motion of the bound neutron. A comparison is carried out with Monte Carlo simulations based on two different parameterizations
of the deuteron wave function. Up to a Fermi momentum of roughly 150MeV/c no significant deviations between experimental and simulated data of various observables were found from which we conclude
that the deuteron can indeed be taken as a valid substitute for the neutron. 相似文献
59.
The problem of two-phase unsteady MHD Couette flow between two parallel infinite plates has been studied taking the viscosity effect of the two phases into consideration. Unified closed form expressions are obtained for the velocities and the skin frictions for both cases of the applied magnetic field being fixed to either the fluid or the moving plate. The novelty of this study is that we have obtained the solution of the unsteady flow using the Laplace transform technique, D’Alemberts method and the Riemann-sum approximation method. The solution obtained is validated by assenting comparisons with the closed form solutions obtained for the steady states which have been derived separately and also by the implicit finite difference method. Graphical result for the velocity of both phases based on the semi-analytical solutions are presented and discussed. A parametric study of some of the physical parameters involved in the problem is conducted. The skin friction for both the fluid and the particle phases decreases with time on both plates until a steady state is reached, it is also observed to decrease with increase in the particle viscosity on the moving plate while an opposite behaviour has been noticed on the stationary plate. 相似文献
60.
Physics of Atomic Nuclei - An Erratum to this paper has been published: https://doi.org/10.1134/S1063778822010082 相似文献