Recurrence formulas for long wavelength asymptotics in the problem of shear flow stability

Recurrence formulas are obtained for the kth term of the long wavelength asymptotics in the stability problem for two-dimensional viscous incompressible shear flows with a nonzero average. It is shown that the critical eigenvalues are odd functions of the wave number, while the critical values of the viscosity are even functions. If the deviation of the velocity from its period-average value is an odd function of spatial variable, the eigenvalues can be found exactly.     

Schemes for excitation of rare earth monoxides in flame laser-induced molecular ionization spectrometry

Laser-induced ionization spectra of PrO, TbO, and CeO molecules in a flame were recorded in the wavelength ranges 440–480 nm and 535–575 nm. Based on study of the spectra, we propose a two-step scheme for excitation of PrO and CeO molecules in which in the first step, the molecule goes to the excited electronic state, while the excitation energy in the second step is selected so that the total energy imparted to the molecule corresponds to its ionization potential. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 4, pp. 544–546, July–August, 2006.     

Isolation of a third component of stellin — A protamine from the gonads of Acipenser stellatus

Moscow Institute of Applied Biotechnology. Translated from Khimiya Prirodnykh Soedinenii, No. 4, p. 590, July–August, 1991.     

Phytoecdysteroids of plants of the genus Lychnis

Siberian Botanical Garden, Tomsk. Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 584–585, July–August, 1991.     

Raman spectra and molecular dynamics of R2NPX2 (R=Me and Et; X=F, Cl, and Br)

The Raman spectra of compounds R₂NPX₂ (R=Me and Et; X=F, Cl, and Br) were studied. The time correlation functions of vibrational and rotational relaxations as well as the characteristic times of these processes were calculated. Conclusions concerning the mechanisms of formation of the contours of the Raman lines with frequencies in the 670–705 cm⁻¹ range corresponding to the totally symmetric vibrations of the P-N bond in the R₂NPX₂ molecules were drawan. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 961–967, May 1997.     

The formation of palladium nanocomposite catalysts on the porous silicon used as anodes of fuel cells

Palladium nanoparticles on the porous silicon were synthesized by radiation-chemical reduction in the solution of reversed micelles. The Pd nanoparticles obtained are electron deficient. The porosity, the type of conductivity, the silicon matrix pore geometry, and precursor parameters influence the size, the shape and the charge state of palladium catalysts. The mechanism of H₂ and HCOOH electrooxidation on porous silica in the presence of Pd+/Pd redox pair is proposed.     

Kinetics of the formation of Liesegang rings

The kinetics of the formation of Liesegang rings is considered and they are classified. The relationship between the position of the propagating diffusion front and the moments of the formation of Liesegang rings is shown. In order to describe the formation processes of the Liesegang rings a generalized model based on the diffusion equation hierarchy is proposed. The kinetics of changes in the dispersed phase sizes at the initial stage of the formation of Liesegang rings is studied.     

Optical and Electrical Characteristics of Polymer Films Modified with Nanostructured Silver Aggregates

To study the formation of a new dispersed phase in polymer layers, the absorption of radiation-generated silver aggregates in cellophane films was examined. Stable silver nanoparticles were prepared by the radiation-chemical reduction of silver ions in a solution of inverted micelles of the composition AgNO₃(AgClO₄)/H₂O/AOT/octane. On irradiation of cellophane films immersed in a micellar solution, the formed silver aggregates Ag^m+ _nbecame incorporated into the films. The modified films exhibited a stable yellow color. The intensity of an optical absorption band of the films with _max 420–440 nm increased proportionally to the radiation dose absorbed by an aqueous micellar solution. The light sensitivity of these films was examined. A 35-min exposure of the films at = 365 nm resulted in an increase in the intensity of the main absorption band by 17% and in a bathochromic shift of the maximum. The electrical characteristics of modified films were determined depending on the radiation dose. It was found that the incorporation of nanostructured silver clusters exhibiting the characteristic optical absorption band with _max 420–440 nm increased the conductivity of cellophane films by two to three orders of magnitude.