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1.
d 《European Journal of Combinatorics》2002,23(8):1079
Assume that d ≥ 4. Then there exists a d -dimensional dual hyperoval in PG(d + n, 2) for d + 1 ≤ n ≤ 3 d − 7. 相似文献
2.
J. Kircher M. Cardona M. Alouani S. Gopalan O. Jepsen O. K. Andersen
E. Kaldis
J. Karpinski S. Rusieki 《Physica C: Superconductivity and its Applications》1992,200(3-4):413-417We report results of ellipsometric measurements of the dielectric tensor of YBa2Cu4O8 as well as calculations employing density functional theory in the local density approximation (LDA). For the computation of the one-electron eigenvalues and states the linear-muffin-tin-orbital method (LMTO) was used. Measured and calculated results show good agreement. In particular, the calculation predicts different band structures for YBa2Cu3O7 and YBa2Cu4O8 in the vicinity of the Fermi energy which lead to significant differences in the optical spectra. One such difference is a region of small ε2 in the near infrared which is a fingerprint of the high (relative to the top of the highest fully occupied band) Fermi energy as compared to the situation in YBa2Cu3O7. Our experimental results confirm the theoretical findings. 相似文献
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6.
S. V. Meshkov
D. V. Berkov
《Physics letters. A》1992,170(6):448-453We investigate this problem by two methods. In the first one the density of states is determined from its moment expansion. In the second approach an imaginary time Green function obtained by a special world line Monte Carlo algorithm is analytically continued to the real frequency axis. 相似文献
7.
Sam I. Ahonkhai
Andreas N
llePeter Behr
Horst Heydtmann 《Journal of photochemistry and photobiology. A, Chemistry》1994,80(1-3):389-392Experimental results are presented of a Fourier transform IR product study at 298 K of the reaction system CFO+O2 at oxygen pressures between 3 and 250 mbar. Pulsed photolysis of oxalyl fluoride (CFO)2 or formyl fluoride (CHFO) at 193 nm was used to produce CFO. As stable products we detected bis-fluoroformyl peroxide, carbonyl fluoride and carbon dioxide. The yields of the peroxide and of CF2O were measured as a function of [O2]/[precursor] and are discussed qualitatively. 相似文献
8.
王同科 《高等学校计算数学学报(英文版)》2002,11(2):213-225
1 IntroductionFinitevolumeelementmethodorFVEMusesavolumeintegralformulationofthedif ferentialequationwithafinitepartitioningsetofvolumetodiscretizetheequation ,thenre strictstheadmissiblefunctionstoalinearfiniteelementspacetodiscretizethesolution ([1 -4 ] ) .… 相似文献
9.
V. I. Karpman
A. G. Shagalov
《Physics letters. A》1991,160(6):538-540The self-focusing described by the nonlinear Schrödinger equation with a higher-order derivative term is investigated numerically. We demonstrate that, depending on the sign before this term, it may lead in the final stage either to defocusing or to a steady homogeneous wave beam. In both cases the transition to the final state is shown to be oscillatory. 相似文献
10.
A. Yu. Khodjamirian
A. G. Oganessian
《Nuclear Physics B》1992,380(3):431-443The leading nonperturbative contribution to the cross section of charm production in two-photon collisions is calculated in QCD. Operator expansion is used and the c-quark interaction with vacuum gluon condensate is taken into account. As a result, the moments of the charm contribution to the photon structure function are obtained. The moments with sufficiently high numbers turn out to be sensitive to the gluon condensate. 相似文献