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51.
The three-dimensional unsteady problem of the action of a localized radiation pulse on an aluminum plate of finite thickness
in a tangential airflow is solved on the basis of the Euler equations in the gas phase and the heat conduction equation in
the solid. The process is accompanied by the intense evaporation of plate material and the subsequent (after the action of
the radiation pulse ceases) intense condensation of aluminum vapor and condensate particles on the surface. The problem is
solved on the assumption that the surface is not screened by its disintegration products and the processes associated with
the self-radiation of the gas are disregarded. Heat pulses of intensityq=106−107 W/cm2 and durationt
i
≈10−4 sec are investigated. Various regimes are calculated and the effect of the governing parameters on the impulse transmitted
to the surface and ablation of the target material is established. A nontraditional approach, based on the idea of statistical
modeling of the motion of an inviscid non-heat-conducting gas at the kinetic level, is used for solving the gas dynamic problem.
The application of the approach in question to the solution of problems of this class is justified.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No.1, pp. 139–146, January–February,
1994. 相似文献
52.
A. A. Abramov 《Computational Mathematics and Mathematical Physics》2011,51(1):35-39
A modification of the method proposed earlier by the author for solving nonlinear self-adjoint eigenvalue problems for linear
Hamiltonian systems of ordinary differential equations is examined. The basic assumption is that the initial data (that is,
the system matrix and the matrices specifying the boundary conditions) are monotone functions of the spectral parameter. 相似文献
53.
The character of interatomic interaction in ferrite Mg0.54Zn0.46Fe2O4 was studied using the x-ray spectroscopy technique and theoretically. It was found that the electronic structure of samples is rearranged during annealing at high temperatures (1280°C, 0.5–0.8 h). The electronic structure rearrangement was shown to be associated with multilayered ferrite metallization in which alternating layers with metallic and ionic-covalent bonds form. 相似文献
54.
Viktor Abramov 《Advances in Applied Clifford Algebras》2007,17(4):577-588
We construct a q-analog of exterior calculus with a differential d satisfying d
N
= 0, where N ≥ 2 and q is a primitive Nth root of unity, on a noncommutative space and introduce a notion of a q-differential k-form. A noncommutative space we consider is a reduced quantum plane. Our construction of a q-analog of exterior calculus is based on a generalized Clifford algebra with four generators and on a graded q-differential algebra. We study the structure of the algebra of q-differential forms on a reduced quantum plane and show that the first order calculus induced by the differential d is a coordinate calculus. The explicit formulae for partial derivatives of this first order calculus are found. 相似文献
55.
B. M. Abramov I. A. Dukhovskoy V. S. Fedorets A. I. Khanov Yu S. Krestnikov A. P. Krutenkova V. V. Kulikov M. A. Matsyuk I. A. Radkevich A. N. Starodumov A. I. Sutormin 《Zeitschrift fur Physik C Particles and Fields》1995,69(1):409-413
The effective mass spectrum of two protons from the reactionp+n→pp+π ?(backward) was investigated. The work was carried out at ITEP using a 3-meter magnet spectrometer and a proton beam of 1.98GeV/c momentum. Liquid deuterium was used as a target. The presented mass spectrum includes about 34000 events. No statistically significant signals from narrow dibaryons were found in the mass region 1.89–2.17GeV/c 2; the upper limits on narrow dibaryon production cross-section are given. At a mass of 1.8775GeV/c 2 a narrow enhancement was found. A more detailed investigation of the observed phenomenon is needed. 相似文献
56.
A new solution to modified Bloch equations for a diatomic quantum system consisting of two identical interacting atoms in a field of high-intensity continuous radiation is obtained. On the basis of this solution, the existence of nonlinear sized resonances whose properties strongly depend on the atomic spacing, on the polarization of the external field of radiation, and on the initial inversions of atoms constituting a nanostructural object is shown. Dispersion dependences of induced dipole moments and inversions of atoms of the object are investigated theoretically in the region of sized resonances for various irradiation conditions. 相似文献
57.
58.
Literature data on the structure, physicochemical properties, and transformations of imidazole-2-thiones and their benzo analogs are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1587–1599, December, 1988.Original Article submitted November 19, 1986: revision submitted March 18, 1988. 相似文献
59.
A theoretical study is made of the role of local phonon modes in a high-temperature ferroelectromagnet-superconductor. Angular states of magnetic moments of ions in the magnetic structure of a high-TC superconductor are shown to be possible. A model of ferroelectric and superconducting transition is proposed. Theoretical estimates of the physical parameters are made and compared with experimental data.Deceased.Donetsk Physicotechnical Institute, Academy of Sciences of the Ukraine. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 5–19, July, 1993. 相似文献
60.