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991.
Methods and algorithms for the solution of spectral problems of singular and regular pencils D(λ, μ)=A(μ)-λB(μ) of polynomial
matrices A(μ) and B(μ) are suggested (the separation of continuous and discrete spectra, the computation of points of a discrete
spectrum with the corresponding, Jordan chains, the computation of minimal indices and a minimal basis of polynomial solutions,
the computation of the determinant of a regular pencil). Bibliography: 13 titles.
Translated by V. N. Kublanovskaya
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 202, 1992, pp. 26–70 相似文献
992.
I. N. Shchitov 《Ukrainian Mathematical Journal》1993,45(4):598-608
Under the condition that a degenerate system has an exponentially stable integral manifold, an asymptotic expansion of the Cauchy problem that generalizes the well known Vasil'eva expansion is constructed for a perturbed system.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 4, pp. 552–560, April, 1993. 相似文献
993.
994.
995.
996.
G. A. Stergioudis 《Zeitschrift für Physik B Condensed Matter》1993,93(1):1-4
The tendency of boron-containing, iron-based glasses to show non monotonic changes of Curie Temperature (T
c
) and room temperature saturation magnetization (SM) was examined by magnetic measurements and Mossbauer spectroscopy. Depending on B/Fe ratio theT
c
and SM first increased up to a maximum value and then steadily decreased, probably because of a shortrange ordering, due to the strong chemical interaction between iron and boron atoms, leading iron atoms in vicinity with Fe-atoms rather than another TM-atom. Finally, the phenomenon becomes analogous to the order-disorder phenomenon in crystalline alloys. An observed unusual crystallization behaviour, consisting of heterogeneous nucleation, was also ascribed to this ordering, which leads to the formation of associations, acting as the first nuclei of crystallization. 相似文献
997.
998.
999.
This review generalizes the latest advances in the chemical synthesis of the plant growth regulators brassinosteroids in 1990–1994.Institute of Bioorganic Chemistry, Belarus Academy of Sciences, 220141, Minsk, ul. Zhodinskaya, 5/2. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 507–544, July–August, 1997. 相似文献
1000.
By noting changes in the color of samples in a polarization microscope with varying degree of birefringence, the effect of
a weak static magnetic fields (2 and 4 kOe) on molecules of glassy polymers has been observed. Variations in the nonmonotonicity
of the rate of discontinuous creep at +18° were studied interferometrically. It is shown that the abruptness of the deformation
jumps varies in a magnetic field, where this abruptness is assumed to be due to the existence of strong physical junctions
between the kinetic units of deformation. The reactivity of the polymers to the magnetic field stands in satisfactory correspondence
with their magnetic susceptibilities. Results show that such nonmagnetic materials as glassy polymers can noticeably alter
their deformational properties in response to the action of magnetic fields.
Fiz. Tverd. Tela (St. Petersburg) 39, 1690–1692 (September 1997) 相似文献