The M$\stackrel{..}{o}$ssbauer oxygen parameter of ferrite spinels
The M$\stackrel{..}{o}$ssbauer oxygen parameter of ferrite spinels
V.I. Nikolaev, V.S. Rusakov, A.M. Shipilin
Data about the spectral shifts for ferrite-spinels which contain Fе$^{3+}$ ions in both cation sublattices may be used to acquire the values of the oxygen parameter u and its changes caused by different factors. The basis of this method is a formalism from the theory of molecular orbitals which makes it possible to quite precisely calculate the dependence of the contributions to spectral shifts caused by "covalency effects" on the cation to anion distances in the structure of the spinel. A correlation of change in the difference in the shifts of partial spectra and internal reordering of the structure with a preservation of symmetry is established.
Show AbstractThe effect of compensational disorder on the mobility and Hall factors in high resistance silicon
The effect of compensational disorder on the mobility and Hall factors in high resistance silicon
V.V. Ostroborodova, L.G. Radovil'skaya
The galvanomagnetic properties of undoped n- and p-type silicon with shadow specific resistances of $\rho=1-100$ k$\Omega\cdot$cm are investigated. The dependences of the Hall constant $R$ and the effective "magnetic resistance" $\rho^{\ast}$ on the magnetic field $B$ in a range of $B=0,3\div 22$ kG and on the photomagnetic currents $i_{\text{PM}}$ at $B\leq 15$ kG were measured at SOK. The patterns of admixture bipolarity in the presence of a compensating disorder in the samples are discussed. It is established that the relations $R(B)$ and $\rho^{\ast} (B)$ may serve as indicators of the heterogeneity of this type.
Show AbstractPerturbations in the external orbit of the multiple star system ${\xi}$Ursa Major
Perturbations in the external orbit of the multiple star system ${\xi}$Ursa Major
A.A. Orlov, N.A. Solovaya
Perturbations are calculated in the external orbit of the multistar system ${\xi}$Ursa Major using formulas from a theory developed by the authors. A comparison is performed of the changes in the $i_{2}$, $\omega_{2}$, and $\Omega_{2}$ elements calculated using formulas from the theory and deduced by Heintz from observation. The comparison shows that the order of magnitude of these changes in any case is the same, although their numerical values are different. For a more precise comparison of the results, new processing of observations of the ${\xi}$Ursa Major system must be performed, with which the perturbations of the external orbit should be calculated using the authors' formulas.
Show AbstractQuasiconventional oscillation modes of certain nonlinear systems of differential equations with delay
Quasiconventional oscillation modes of certain nonlinear systems of differential equations with delay
G.N. Medvedev, B.I. Morgunov
Oscillations of links of manipulators are examined. The resulting movements of the manipulators are a superposition of programmed movements and small, rapid oscillations. The delay in the movement equation is taken into consideration. The quasiconventional oscillation modes are investigated using an averaging method.
Show AbstractExoatmospheric study of the spectrum of nuclei of the iron group in an energy range of 100-1000 GeV/nucleon
Exoatmospheric study of the spectrum of nuclei of the iron group in an energy range of 100-1000 GeV/nucleon
I.P. Ivanenko, N.L. Grigorov, Yu.V. Basina, P.V. Vakulov, Yu.Ya. Vasil'ev, R.M. Golynskaya, L.B. Grigor'eva, D.A. Zhuravlev, V.I. Zatsepin, D.I. Il'ichev, A.K. Kazakova, V.D. Kozlov, I.P. Kumpan, Yu.A. Laputin, L.G. Mishchenko, V.M. Nikanorov, L.P. Papina, V.V. Platonov, D.M. Podorozhnyi, I.D. Rapoport, G.A. Samsonov, L.G. Smolenskii, V.A. Sobinyakov, V.K. Sokolov, G.E. Tambovtsev, Ch.A. Tret'yakova, Yu.V. Trigubov, I.M. Fateeva, L.A. Khein, L.O. Chikova, V.Ya. Shestoperov, V.Ya. Shiryaeva, B.M. Yakovlev, I.V. Yashin
An installation consisting of an ionization calorimeter and two Cerenkov charge detectors was irradiated on a satellite. Data about the spectrum of nuclei of the iron group in an energy range of $10^{12}-10^{14}$ eV are acquired.
Show AbstractA Gunn diode microwave generator stabilized by a dielectric disk resonator
A Gunn diode microwave generator stabilized by a dielectric disk resonator
I.I. Minakova, V.I. Panov, B.G. Simeonova (Bulgaria)
The results are cited of experimental investigations of the frequency characteristics of a microwave (MW) generator stabilized by a multimode dielectric resonator with modes which have different quality factors. The possibility of even change in the type of frequency curve and selection of stable modes through adjusting the resonating communication line between the generator and the stabilizing resonator is shown.
Show AbstractConsideration of distortions of a crystalline structure near the surface in the theory of slipping X-ray diffraction
Consideration of distortions of a crystalline structure near the surface in the theory of slipping X-ray diffraction
M.A. Andreeva
A matrix theory is developed for radiation propagation in a plane-layered medium with slipping X-ray diffraction in conditions of full external reflection (FERXD) for the case of a gradual change in the "degree of amorphization" of the surface layer of a crystal.
Show AbstractCertain characteristics of the charged states of oxygen in high resistance gallium arsenide
Certain characteristics of the charged states of oxygen in high resistance gallium arsenide
V.A. Morozova, V.V. Ostroborodova
Investigations are performed of the dark and photo-Hall parameters, the optical absorption, and the photoconductivity of gallium arsenide samples doped with oxygen with varying filling of the deep donor (D) level with O electrons. It is explained that in a temperature range of 10-300 K in maximally high resistance GaAs with $\rho=2{\cdot}10^{9}$ $\Omega\cdot$cm there are no noticeable rechargings of the D-level with O, while at 10-50 K neutral scattering dominates in such material. A conclusion is drawn about the concentration and nature of the D-centers. The energy of ionization of the D-level of oxygen is $\varepsilon_{\text{D$\nu$}}\approx$0.76 eV and is not changed with temperature in the range of 10-300 K.
Show AbstractThe role of In$^{3+}$ ions in the formation of the magneticproperties of ferrite-spinel
The role of In$^{3+}$ ions in the formation of the magneticproperties of ferrite-spinel
K.P. Belov, A.N. Goryaga, A.I. Kokorev
The temperature relations of magnetization and the magnetocaloric effect of NiInFeO$_{4}$ ferrite are identified and they are compared with the analogous results for the Ni$_{0,2}$Zn$_{0,8}$Fe$_{2}$O$_{4}$ ferrite, in which the magnetic structure has a frustrated character. It is established that the diamagnetic field ions In$^{3+}$ not being magnetic vacancies, participate in indirect exchange interaction; a Neel spin ordering is observed in the investigated ferrite.
Show AbstractTransformation of low frequency internal waves over medium scale underwater obstacles
Transformation of low frequency internal waves over medium scale underwater obstacles
M.B. Timonov, N.K. Shelkovnikov
A perturbation method is used to find approximate analytical solution to the problem about transformation of a low frequency internal wave in a two-layer rotating liquid over a localized underwater obstacle of a mesoscale length. It is shown that the perturbation of a wave in the upper layer is proportional to its relative thickness and for actual oceanic stratification in the presence of the seasonal pycnocline is insignificant even for obstacles whose height is comparable with the thickness of the lower layer.
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