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11.
A cube factorization of the complete graph on n vertices, Kn, is a 3‐factorization of Kn in which the components of each factor are cubes. We show that there exists a cube factorization of Kn if and only if n ≡ 16 (mod 24), thus providing a new family of uniform 3‐factorizations as well as a partial solution to an open problem posed by Kotzig in 1979. © 2004 Wiley Periodicals, Inc. 相似文献
12.
Using a representation of multichannel quantum defect theory in terms of a quantum Poincaré map for bound Rydberg molecules, we apply Jung's scattering map to derive a generalized quantum map, that includes the continuum. We show that this representation not only simplifies the understanding of the method, but moreover produces considerable numerical advantages. Finally we show under what circumstances the usual semi-classical approximations yield satisfactory results. In particular we see that singularities that cause problems in semi-classics are irrelevant to the quantum map. 相似文献
13.
Dinesh Topwal U. Manju Sugata Ray S. Raj D. D. Sarma S. R. Krishnakumar M. Bertolo S. La Rosa G. Cautero 《Journal of Chemical Sciences》2006,118(1):87-92
Disordered Sr2FeMoO6 shows a drastic reduction in saturation magnetization compared to highly ordered samples, moreover magnetization as a function
of the temperature for different disordered samples shows qualitatively different behaviours. We investigate the origin of
such diversity by performing spatially resolved photoemission spectroscopy on various disordered samples. Our results establish
that extensive electronic inhomogeneity, arising most probably from an underlying chemical inhomogeneity in disordered samples, is
responsible for the observed magnetic inhomogeneity. It is further pointed out that these inhomogeneities are connected with
composition fluctuations of the type Sr2Fe1+x
Mo1-x
O6 with Fe-rich (x > 0) and Mo-rich (x < 0) regions.
Dedicated to Prof J Gopalakrishnan on his 62nd birthday. 相似文献
14.
15.
A difference between the thermal behaviour of the isotropic and liquid-crystalline state of sonicated DNA in aqueous salt solution containing poly(ethyleneglycol)(PEG) has been demonstrated. On cooling, a different degree of renaturation of thermally denaturated DNA is observed between samples which form the isotropic state and more concentrated samples which on cooling form the cholesteric state. 相似文献
16.
Carlos E. Alciaturi Thais Montero Carlos De La Cruz Marcos E. Escobar 《Analytica chimica acta》1997,340(1-3):233-240
Reduction of the representation of infrared spectra from coal samples by osculating polynomials of degree nine is discussed. The reduced representation contains polynomial coefficients of order zero to four. Mathematical models of the original spectra are obtained by linear combination of the coefficients. These compressed models are statistically correlated to coal properties, namely, volatile matter, fixed carbon, ash content, heating value, hydrogen, carbon, sulphur, nitrogen, and maximum vitrinite reflectance, and the results are compared with those previously obtained from second derivatives of the same spectra. The use of compressed data, while giving slightly better correlations for some of the properties, has the advantage of requiring less computational time. 相似文献
17.
18.
Ilda Abe Rafael E. de Ges Jos L. Fabris Hypolito J. Kalinowski Mrcia Müller Meire C. Fugihara Rosane Falate Barbara W. Diesel Ricardo C. Kamikawachi Carmen L. Barbosa 《Optics and Lasers in Engineering》2003,39(5-6):537-548
In this work, we report production and modelling of both Bragg gratings and rocking filters in high birefringence fibre optics. Bragg gratings are produced by UV (257.0 nm) external interferometric exposition of a frequency-doubled Ar+ ion laser, whereas for rocking filters formation the visible Ar+ ion laser lines in 488.0 and 514.5 nm are used in an internal method. The spectral characteristics due to the birefringence properties are studied through numerical methods and experimental techniques. The spectral responsivity of the structures under temperature changes and stress application is presented. 相似文献
19.
THE FIRST EXPERIMENT OF A THz GYROTRON WITH A PULSE MAGNET 总被引:1,自引:0,他引:1
T. Idehara H. Tsuchiya O. Watanabe La Agusu S. Mitsudo 《International Journal of Infrared and Millimeter Waves》2006,27(3):319-331
A THz gyrotron with a pulse magnet has been designed, constructed and operated in FIR FU. It is developed as one of high frequency
gyrotrons included in Gyrotron FU Series. The gyrotron has already achieved the first experimental result for high frequency
operations whose radiation frequency exceeds 1 THz. In this paper, the design detail and the operation test results for sub-terahertz
to terahertz range are described. The second harmonic operation is confirmed experimentally at the expected frequency of 1.005
THz due to TE6,11 cavity mode at the magnetic field intensity of 19.0 T. 相似文献
20.