Direct measurement of multiphoton molecular absorption of IR laser radiation by pyroelectric detector

The applicability of a pyroelectric detector (PED) to multiphoton absorption measurements (MPA) under ir laser excitation of molecules was examined. The possibility of MPA measurement of SF₆ molecules in the pressure range of 10⁻³÷10⁻¹ Torr with a time resolution of ∼ 7 μs has been shown. It has been demonstrated that the degree of vibrational relaxation of highly vibrationally excited molecules at PED surface does not depend on excitation level under the studied conditions.     

Search for parity-nonconservation effects in deep-inelastic μ-N interaction

The difference of the cross sections for deep inelastic scattering of muons with average momenta 21 GeV/c with right and left helicity at large angles, i.e., with large momentum transfer, has been measured. No statistically-significant dependence of cross sections on the longitudinal polarization of muons has been found, i.e. no parity-nonconservation effects in deep inelastic μN interaction have been observed. The magnitude of the cross-section asymmetry $\text{R =}\text{[〈σ}{}_{\mathrm{<mtext>R</mtext>}}\text{〉 ? 〈σ}{}_{\mathrm{<mtext>L</mtext>}}\text{〉]}\text{[〈σ}{}_{\mathrm{<mtext>R</mtext>}}\text{〉+ + 〈σ}{}_{\mathrm{<mtext>L</mtext>}}\text{〉]}$ may be represented as R = β〈Q²〉 = (? 4 ± 6) × 10^?3 〈Q², (GeV/c)²〉. The limitations G_o^(μ) = (+ 6 ± 10)G have been obtained for the constant G_o^(μ) of vector-axial interaction $\text{(}\text{G}{}_{\mathrm{<mtext>o</mtext>}}{}^{\mathrm{(\mu )}}\text{2}\text{) [}\text{μ}\text{γα(1 + γ}{}_5\text{)μ] J}{}_{\mathrm{\alpha }}{}^{\mathrm{<mtext>o</mtext>}}$ (hadron, V-A).     

X-ray study of the structure of multicomponent glasses based on mining-industry waste

The short-range order and microinhomogeneity structure of laboratory samples of glasses belonging to the diopside-orthoclase-apatite system with different percentages of components were investigated by X-ray diffraction and small-angle scattering. A correlation between a change in the chemical composition of a glass, causing its segregation, and the short-range order parameters was ascertained: an increase in the apatite content leads to a change in the short-range order parameters. The use of the X-ray small-angle scattering technique made it possible to reveal inhomogeneities of electron density in the glasses under study and the dependence of the sizes of inhomogeneities on the glass composition.     

Process optimisation of MOVPE growth by numerical modelling of transport phenomena including thermal radiation

A global transport model for the MOVPE of III–V growth based on the finite volume solution of coupled flow, heat and mass transfer, including detailed radiative transfer, multicomponent diffusion and homogeneous and heterogeneous chemical reactions, is presented. For radiative transfer modelling, a combined approach is used of grey-diffuse view-factor based heat flux exchange between the semi-transparent reactor walls through the transparent reactor interior, and a spherical harmonics approximation for the radiative-conductive heat transfer problem in participating massive quartz elements with complex shapes. The described modelling approach is applied to the horizontal multiwafer radial flow Planetary Reactor™, validated experimentally and used for process improvements. The mutual interaction of changing radiation properties at internal solid boundaries due to semiconductor coatings and thermal behaviour in that particular MOVPE reactor is discussed.     

Nitrogen-doped alumina carrier for sintering resistant gold supported catalysts

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Evolution of cylindrical waves of finite amplitude diverging in heated gas

The behavior of weak cylindrical and spherical waves of finite amplitude in a dissipative gas close to the wave front is described by a generalized Burgers equation [1]. The construction of various types of solution of this equation for large Reynolds numbers is known [1–3]. For the evolution of diverging perturbations in heated gas, a study of this equation in the region Re < 1, where Re is the effective Reynolds number at the initial time, is of interest. The direct application of the method of successive approximations to this problem is restricted by the condition Re 1, and becomes more and more difficult as the Reynolds number grows and the form of the initial wave becomes more complex. This paper describes in explicit form the construction of an approximate solution of the Cauchy problem for the generalized Burgers equation in the case of cylindrical symmetry in the region Re < 1. The initial wave selected is the arbitrary perturbation represented by a function which is absolutely integrable on the real axis. An integral estimate of the error as a function of Re is given. The question of how the structure of the solution corresponds to the Cole-Hopf transformation is discussed. All the treatment can easily be extended to the spherically symmetric case.Translated from Izvestlya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 150–153, July–August, 1985.     

Some Properties of Chemically Deposited Ni-B Coatings

The influence exerted by impurities present in dimethylaminoborane and in solutions used for deposition of nickel-boron coatings on their properties was studied.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 2, 2005, pp. 200–203.Original Russian Text Copyright © 2005 by Prusov, Makarov.     

A Study of Structure and Surface Properties of Cleaved Mica Particles

The structure of cleaved mica particles and the influence of cleavage conditions on surface prop- erties of mica were studied by IR spectroscopy.