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121.
A.J.W Hilton 《Journal of Combinatorial Theory, Series B》1984,36(2):125-134
It is well known that K2n + 1 can be decomposed into n edge-disjoint Hamilton cycles. A novel method for constructing Hamiltonian decompositions of K2n + 1 is given and a procedure for obtaining all Hamiltonian decompositions of of K2n + 1 is outlined. This method is applied to find a necessary and sufficient condition for a decomposition of the edge set of Kr (r ≤ 2n) into n classes, each class consisting of disjoint paths to be extendible to a Hamiltonian decomposition of K2n + 1 so that each of the classes forms part of a Hamilton cycle. 相似文献
122.
123.
High-average-power Nd:YAG planar waveguide laser that is face pumped by 10 laser diode bars 总被引:2,自引:0,他引:2
A planar waveguide Nd:YAG laser is pumped with 430 W of power from 10 laser diode bars to produce a multimode output power of 150 W at an optical efficiency of 35%. Use of a hybrid resonator of the positive-branch confocal unstable type for the lateral axis and of one of the near-case I waveguide type for the transverse axis increased the laser brightness by a factor of ~26 with only 12% less power than in the multimode case. 相似文献
124.
Optical orientation of spin-polarized heavy and light holes followed by relaxation to other valence subband states has been observed unambiguously in undoped bulk GaAs in spite of the extremely short spin relaxation time. The measured relaxation time for the heavy holes is 110 fs +/-10%. The results are relevant for applications such as interpretation of spin-polarized transport in semiconductors as well as the assessment of feasibility of hole-based spin-transport devices which relies on precise knowledge of the hole-spin relaxation time. 相似文献
125.
126.
David Wilbur Wayne B. Manning Bruce D. Hilton Gary M. Muschik 《Magnetic resonance in chemistry : MRC》1982,18(2):63-67
Benz[a]anthracene-7, 12-dione, eight monomethoxybenz[a]anthracene-7, 12-diones and two dimethoxybenz[a]anthracene-7, 12-diones were analyzed by 13C and 1H NMR. All 13C and 1H resonances have been assigned. Substituent effects on the 13C chemical shifts are discussed. 相似文献
127.
We demonstrate that emission-induced self-organization of two-level atoms can effect strong damping of the sample's center-of-mass motion. When illuminated by far-detuned light, cold cesium atoms assemble into a density grating that efficiently diffracts the incident light into an optical resonator. We observe random phase jumps of pi in the emitted light, confirming spontaneous symmetry breaking in the atomic self-organization. The Bragg diffraction results in a collective friction force with center-of-mass deceleration up to 1000 m/s(2) that is effective even for an open atomic transition. 相似文献
128.
Summary By a natural process of relativization groups Extn(A, φ), πn(A, φ) are defined in any abelian category with sufficient injectives and projectives. Functoriality in φ i spro. ved and
excision properties are established; and the groups are shown to behave well under suspension. The technique involves an interplay
of different mapping-cone constructions
In memory of Guido Castelnuovo, on the occasion of the first centenary of his birth. 相似文献
129.
130.
P.R. Hilton S. Nordholm N.S. Hush 《Journal of Electron Spectroscopy and Related Phenomena》1980,18(1):101-119
The ground-state inversion method, which we have previously developed for the calculation of atomic cross-sections [ 29 ], is applied to the calculation of molecular photoionization cross-sections. These are obtained as a weighted sum of atomic subshell cross-sections plus multi-centre interference terms. The atomic cross-sections are calculated directly for the atomic functions which when summed over centre and symmetry yield the molecular orbital wave function. The use of the ground-state inversion method for this allows the effect of the molecular environment on the atomic cross-sections to be calculated. Multi-centre terms are estimated on the basis of an effective plane-wave expression for this contribution to the total cross-section. Finally the method is applied to the range of photon energies from 0 to 44 eV where atomic extrapolation procedures have not previously been tested. Results obtained for H2, N2 and CO show good agreement with experiment, particularly when interference effects and effects of the molecular environment on the atomic cross-sections are included. The accuracy is very much better than that of previous plane-wave and orthogonalized plane-wave methods, and can stand comparison with that of recent more sophisticated approaches. It is a feature of the method that calculation of cross-sections either of atoms or of large molecules requires very little computer time, provided that good quality wave functions are available, and it is then of considerable potential practical interest for photoelectron spectroscopy. 相似文献