Artificial Monte Carlo interactions for solving some linear problems

A method of artificial interaction for Monte Carlo solution of ordinary differential equations with respect to probability measures is proposed. Under some conditions this method is advantageous over the standard method. A theoretical comparison of the complexity of the corresponding algorithms is provided. Also, results of numerical experiments are discussed.     

Acoustic Field Effect on Electrochemiluminescence of Organic Molecules in Solutions

Electrochemical reactions in solutions causing the production of electrochemiluminescence (ECL) have been studied already for more than ten years^1–4. In the main the ECL mechanism is established, the main regularities of this interesting phenomenon are determined. The attention is paid to the ECL in connection with the fact that its radiation gives a vast information about the electrochemical reactions in solutions. Moreover on this basis an effective and convenient transformators of the electrical signals into light can be carried out (the quantum efficiency is 20% for some solutions⁵). As a rule the ECL experiments are made under conditions controlled by an ordinary or convective diffusion. In this paper the results of investigations of the ECL upon condition of great external disturbances of solution whic occure due to the applicatin of the ultrasonic fields to the cell are given. To our Knowledge suvh investigations have not been undertaken earlier.     

Anodic Oxidation of Silver Alloys in Concentrated Sulfuric Acid Solutions

Anodic oxidation of Ag–Cu and Ag–Pd alloys in concentrated sulfuric acid solutions is studied by cyclic voltammetry. Influence of electronegative (Cu) and electropositive (Pd) constituents on the rate and mechanism of the silver electrooxidation in non-steady-state conditions is revealed. The maximum silver oxidation current increases with the copper content due to a decreased H₂SO₄ concentration in the near-electrode layer and increased solubility of passivating phase Ag₂SO₄. The mechanism of ionization of palladium-doped silver is complicated by two electrochemical reactions involving the formation of Ag₂SO₄ and Ag⁺ _solv.     

The application of thermodynamic perturbation theory to the calculation of excess free energy of small systems: 2. Excess free energy and disjoining pressure in the wetting layer of apolar liquid

Isotherms of disjoining pressure in the wetting film of apolar liquid on unmodified and modified solid surfaces were studied based on the thermodynamic perturbation theory. Specific calculations were performed for two systems: (1) the wetting film of decane on aluminum surface and (2) the wetting film of decane on aluminum surface modified by pentanol. It was shown that the results of calculation agree with experimental data.Translated from Kolloidnyi Zhurnal, Vol. 66, No. 6, 2004, pp. 850–855.Original Russian Text Copyright © 2004 by Samsonov, Rumyantsev, Khashin.     

Barkhausen effect in stepped motion of a plane domain boundary in gadolinium molybdate

Barkhausen pulses generated in stepped motion of a single plane domain boundary (PDB) are investigated experimentally in single-crystalline wafers of the extrinsic ferroelastic ferroelectric gadolinium molybdate containing artificial pinning centers of the “field inhomogeneity” type near the edges of the sample. Two scenarios of the evolution of a PDB in interaction with “defects” are proposed on the basis of analyzing the shape of the pulses in a linearly increasing field: small changes of the pulse shape in a weak field and the generation of wedge domains in a strong field. The proposed mechanism of PDB motion due to the generation of steps near the edge of the sample and their longitudinal motion provides a means for explaining the experimentally observed linear field dependence of the PDB velocity and for determining the velocity of the steps. Fiz. Tverd. Tela (St. Petersburg) 41, 301–305 (February 1999)     

Probing States of a Double Acceptor in CdHgTe Heterostructures via Optical Gating

JETP Letters - Photoconductivity spectra in a HgTe/CdHgTe double quantum well with a normal band structure have been studied. Photosensitivity bands associated with the ionization of a mercury...     

Electronic absorption spectra and acid-base and ligand properties of alkyl-substituted biladiene-a,c

The influence of the nature of a solvating medium on the chromophore properties and stability of alkyl-substituted biladiene-a,c dihydrobromide, a synthetic analogue of a bile pigment bilirubin, was analyzed. The results of the spectrophotometric study of the protonation of a tetrapyrrol ligand and of the complex formation with Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) acetates in DMF at 298.15 K were considered. Depending on the nature of a complex-forming cation and concentrations of reagents in solution the formation of complexes of three various types is possible: porphyrin-like (1:1), binuclear with different ligands (2:1), and binuclear biligand (2:2). The nature of metal cation renders essential influence on the formation of coordination polyhedra of the metal chelates with various structure.     

Polarization switching in heterophase nanostructures: PLZT relaxor ceramics

The polarization switching is experimentally investigated in hot-pressed PLZT-x/65/35 ceramics with a lanthanum content from 5 to 12 at. %. The specific features in the temperature dependence of the polarization switching in a heterophase state are interpreted by analyzing the change in the switched charge measured over wide ranges of fields and temperatures. Particular emphasis is placed on the role of depolarization fields induced by interphase boundaries. A model of the evolution of polydomain nanostructures with a change in the temperature and in the response to an external field is considered. It is assumed that the low-temperature dielectric anomaly and the temperature hysteresis are associated with the loss of stability of a large-scale domain structure and its transformation into a nanodomain state.     

Effects of crystallization temperature on the growth and doping of autoep it axial gallium arsenide films

Dope concentration measurements have been made on epitaxial gallium arsenide films of (1 11.075) A orientation; there is an optimal temperature range, which corresponds to the minimum impurity concentration and maximum electron mobility. The electrophysical properties and morphology are clearly correlated.Translated from Izvestiya VUZ. Fizika, No. 6, pp. 71–75, June, 1973.