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81.
Stanley E. Payne 《Journal of Geometry》1988,33(1-2):113-128
A spread of PG(3,q), q an odd prime, recently constructed by R. Baker and G. Ebert, when generalized for q an odd prime power is isomorphic to a spread derived by J. A. Thas from a flock of a quadratic cone discovered by J. C. Fisher. The associated generalized quadrangle has an unusual colllneation. 相似文献
82.
J. L. Friar B. F. Gibson G. L. Payne 《Zeitschrift für Physik A Hadrons and Nuclei》1981,301(4):309-318
Three nucleon ground state wave functions are displayed graphically in configuration space. Both the Schrödinger functions and the Faddeev amplitudes from which they are constructed are plotted. It is demonstrated that for the case where the two-nucleon interaction contains strong repulsion at short distances, the Faddeev amplitude bears no resemblance to the Schrödinger function, and is not even positive definite. Furthermore, the Faddeev amplitude is a much smoother function of the three independent coordinate variables, and is therefore much easier to calculate. Certain intuitive features of the Schrödinger wave function are seen to be present. 相似文献
83.
H. A. Levine M. H. Protter L. E. Payne 《Mathematical Methods in the Applied Sciences》1985,7(1):210-222
Lower bounds for the eigenvalues of some elliptic equations and elliptic systems over bounded regions are obtained. The bounds are universal in that they depend only upon the volume of the region. Specific applications include the clamped plate, the buckling problem for the clamped plate and the equations of linear elasticity. Our results are consequences of extensions of the methods of Li and Yau (Comm. Mat. Phys. 88 (1983) 309–318) who obtained such results for the eigenvalues of the fixed membrane problem. 相似文献
84.
A general method tor the preparation of 1,4-dihydro-4-quinolone-2-carboxylic acids, especially those which carry alkyl substituents on the ring N-atom, is described. 相似文献
85.
K.W. Bell J.A. Blissett T.A. Broome H.M. Daley J.C. Hart A.L. Lintern R. Maybury A.G. Parham B.T. Payne D.H. Saxon T.G. Walker J.B. Whittaker 《Nuclear Physics B》1983,222(3):389-410
The first measurements of spin-rotation in meson-baryon scattering in the resonance region are presented. These measurements, for the reaction π?p → K0Λ, confirm the main predictions of a previous partial-wave analysis. Comments are made on resonant couplings in the reaction π?p → K0Λ. 相似文献
86.
Further details are given for the assignment of absolute stereochemistry to the acetoxyhydroxy-acid (1) from D. attenuata and the lactone (6) from the var. linearis. The latter also provided a diene-acid shown to have structure 28. Reductive cyclisation of the tosylate of the latter gives a cyclopropane derivative (31). A flavone from the var. linearis is shown to be 5,7-dihydroxy-3,4′,6-trimethoxyflavone (32). 相似文献
87.
In this paper we are concerned with the development of criteria for stabilizing inherently unstable initial-boundary value problems under small errors in the geometry of the underlying domain. We consider in particular the initial-boundary-value problem for the backward heat equation assuming that some error has been made in characterizing the geometry of the domain under consideration. It is shown that solutions which belong to an appropriately defined constraint set depend continuously in L2 on errors in the geometry. 相似文献
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