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971.
The results of measuring the vertical variability of sound fields are presented for a coastal wedge off the Pacific shelf of the Kamchatka peninsula. It is shown that the vertical radius of sound field correlation can reach ~30 m for frequencies within 600–800 Hz. The scatter of the specific parameters of the variability is in rather wide limits depending on the location of a vertical chain of receiving hydrophones, the hydrological conditions, the azimuth angle of the sound source, and the relief and bottom structure of the coastal wedge. 相似文献
972.
S. M. Kostritskii Yu. N. Korkishko V. A. Fedorov M. V. Proyaeva E. A. Baranov 《Technical Physics》2002,47(1):74-79
A change in the spontaneous polarization and the nonlinear susceptibility in H: LiNbO3 waveguides is calculated from experimental data for the shift of the fundamental absorption for variously polarized rays and from IR reflection data in the range of NbO6 octahedron vibrations. It is shown that taking into account the lattice disorder provides good agreement between the theory and experiment. 相似文献
973.
Yu. N. Ovchinnikov I. A. Luk’yanchuk 《Journal of Experimental and Theoretical Physics》2002,94(1):203-215
The problem of the effective conductivity and the distributions of a field and currents is analyzed in a regular two-component system composed of regular triangles. An efficient solution method is developed that admits a generalization to multicomponent systems. 相似文献
974.
Yu. N. Uzikov 《JETP Letters》2002,75(1):5-8
Available data on large-angle nucleon-deuteron elastic scattering Nd→dN below the pion threshold give a signal for three-body forces. The problem exists of the separation of possible subtle aspects of these forces from off-shell effects in two-nucleon potentials. By considering the main mechanisms of the process Nd→dN, we show qualitatively that in the quasi-binary reaction N+d→(NN)+N with the final spin singlet nucleon-nucleon pair in the S-state, the relative contribution of the three-nucleon forces differs substantially from the elastic channel. It gives a new testing basis for the problem in question. 相似文献
975.
We show that the linear and nonlinear Lipschitz extension properties of a metric space are not changed when the original
metric is replaced by a new metric obtained by composition with an arbitrary concave function.
Submitted: January 2001, Revised: February 2001. 相似文献
976.
Popov Yu. V. Korchagina T. K. Chicherina G. V. Ermakova T. A. 《Russian Journal of Organic Chemistry》2002,38(3):350-354
New Schiff bases containing both adamantyl and phenyl fragments in a single molecule were synthesized by condensation of appropriate diamines with aromatic aldehydes. The condensation products were brought into reduction and nucleophilic addition reactions. 相似文献
977.
978.
N. L. Sergovskaya S. A. Chernyak O. V. Shekhter Yu. S. Tsizin 《Chemistry of Heterocyclic Compounds》1991,27(8):888-891
2-Acetyl-4-oxopyrazino[2,1-a]isoquinolines and 4-acyl-2-piperazinones have been synthesized, with interphase catalysis, by the intramolecular N-alkylation of the corresponding diamides.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1107–1109, August, 1991. 相似文献
979.
980.
É. Kh. Absalyamova Yu. I. Kol'tsov N. P. Matshina E. A. Nesmelov N. N. Soboleva 《Journal of Applied Spectroscopy》1991,54(1):79-83
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 54, No. 1, pp. 103–107, January, 1991. 相似文献