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891.
A. Ádám 《Acta Mathematica Hungarica》1989,54(3-4):291-296
892.
The univariate generalized beta- and generalized F-distributions are frequently in recent statistical modellings and applications. They have richer properties than the standard beta- and Snedecor F-distributions and provide more flexibility than these distributions, of which they are natural extensions. Their connection with the Gauss hypergeometric function and Lauricella functions leads to further generalizations and important properties. This article gives a unified and up-to-date treatment of these two generalized distributions using only simple arguments. Proofs are given for some original results and a complete reference to their source is provided for established ones. The important problem of parameter estimation is also studied. 相似文献
893.
894.
A. Z. Dubničková S. Dubnička R. Baldini-Ferroli 《Czechoslovak Journal of Physics》1991,41(11):1075-1081
It is shown that all global analyses of nucleon electromagnetic form factor data predict the electron-positron annihilation into neutron-antineutron cross section (for which there are no data till now) to be in a finite energy region substantially larger than the electron-positron annihilation into the proton-antiproton one.Dedicated to the memory of M. Gmitro. 相似文献
895.
A survey of the contributions of Aldo Cossu in finite geometry is given.
Dedicated to the memory of Professor Aldo Cossu 相似文献
896.
This work describes the first catalytic bismuth-promoted synthesis of polysubstituted guanidines in good yields through the guanylation reaction of N-benzoyl or N-phenylthioureas with primary and secondary amines, but now employing equimolar amounts of each organic reagent. Both bismuth iodine and bismuth nitrate were efficient as inorganic thiophiles at only 5 mol % in relation to substrates, being the first example of inorganic thiophiles acting in guanylation at catalytic levels. 相似文献
897.
Mathematical Notes - 相似文献
898.
V. V. Shelkovnikov Z. M. Ivanova N. A. Orlova T. N. Gerasimova A. I. Plekhanov 《Optics and Spectroscopy》2002,92(6):884-891
The formation and properties of J-aggregates in thin solid films of pseudoisocyanines with long N-alkyl groups, obtained by centrifuging from solutions in organic solvents, were studied. It is shown for the first time that nonsymmetric cyanine dyes, containing a C2H5 group at one nitrogen atom and a C10H21, C15H31, or C18H37 group at another nitrogen atom, spontaneously form J-aggregates stable at room temperature and pressing a narrow absorption band with a half-width at half maximum of 200 cm?1. The thermal stability of J-aggregates in thin films of pseudoisocyanines with alkyl substituents decreases in the following order: C2H5-C2H5> C2H5-C6H13>C2H5-C18H37>C2H5-C10H21>C2H5-C15H31. By introducing 1-octadecyl-2-methylquinolinium iodide in the film, it was found that the J-aggregates studied consist of a small number (2–4) of dye molecules. 相似文献
899.
R. Euler B. Fricke T. Morović W. -D. Sepp A. Rosén 《Zeitschrift für Physik A Hadrons and Nuclei》1980,297(2):101-104
Total energy SCF calculations were performed for noble gas difluorides in a relativistic procedure and compared with analogous non-relativistic calculations. The discrete variational method with numerical basis functions was used. Rather smooth potential energy curves could be obtained. The theoretical Kr-F and Xe-F bond distances were calculated to be 3.5 a.u. and 3.6 a.u. which should be compared with the experimental values of 3.54 a.u. and 3.7 a.u. Although the dissociation energies are off by a factor of about five it was found that ArF2 may be a stable molecule. Theoretical ionization energies for the outer levels reproduce the experimental values for KrF2 and XeF2 to within 2 eV. 相似文献
900.
Pakhurova T. F. Paulin'sh Ya. Ya. Gudrinietse É. Yu. Dashkevich S. V. Ablovatskaya M. V. 《Chemistry of Heterocyclic Compounds》1982,18(11):1217-1217
Chemistry of Heterocyclic Compounds - 相似文献