Kinetics of disilane molecule decomposition on the growth surface of silicon in vacuum gas-phase epitaxy reactors

The range of the characteristic decomposition rates of dihydride molecule radicals adsorbed by the silicon surface in the temperature interval 450?C700°C is experimentally found for a number of kinetic models. A relationship between the rate of silicon atom incorporation into a growing crystal and the characteristic rate of disilane molecule pyrolysis on the silicon surface is found. The temperature dependence of the rate of disilane fragment decomposition on the silicon surface is nonmonotonic, and its run depends on temperature conditions. It is shown that the temperature dependence of the molecular decomposition rate on the growth surface is described by a superposition of two activation curves with various activation energies. The activation energies depend on the peculiarity of interaction between the molecular beam and the silicon surface when the filling of surface states with hydrogen is low and high.     

High-Speed Composite Microactuator Based on Ti<Subscript>2</Subscript>NiCu Alloy with Shape Memory Effect

Samples of microactuators are made of a bimorph composite of Ti₂NiCu alloy with a thermoelastic martensitic transition and the shape memory effect, and their response rate is investigated. The active layer of the composite actuator is a layer of the rapidly quenched Ti₂NiCu alloy, pseudoplastically prestretched, and an amorphous layer of the same alloy is used as an elastic layer. Typical sizes of the microactuator are 30 × 2 × 2 μm. The controlled amplitude of the displacement of the microactuator tip is approximately 1 μm. The response rate of the microactuator was investigated by scanning electron microscopy. Activation of the microactuator was achieved by heating when electric pulses were passed through it. Full activation of the microactuator at frequencies up to 1 kHz was demonstrated; partial activation was observed at frequencies up to 8 kHz. The possibility of operating the device in a self-oscillating mode at frequencies of the order of 100 kHz is demonstrated.     

Test problem generation for quadratic-linear pessimistic bilevel optimization

A generation method of quadratic-linear bilevel optimization test problems in a pessimistic formulation is proposed and justified. Propositions about the exact form and the number of local and global pessimistic solutions in generated problems are proved.     

Mathematical Modeling of the Au-Doping Effect on the Radiative Properties of Porous Polymers in Experiments with Laser and Heavy-Ion Beams

We present results of a theoretical study of the radiative opacity characteristics of plasmas produced by indirect heating of porous carbohydrate (CHO) substances (foams) by laser pulses. The plasma targets are created for further interaction with heavy-ion beams. We consider two different foam substances, namely, cellulose triacetate (TAC, C₁₂H₁₆O₈) and TAC with a small admixture of gold. We discuss important features of the theoretical model, known as the ion model (IM) of plasma, which is used to study the radiative opacity characteristics of complex plasma compositions. Also we study the influence of a small admixture of gold on the radiative opacity characteristics and gas-dynamic processes in the plasma.     

Silicon production from phosphate industry waste (Na2SiF6)

Production of salable goods from industrial waste can become an additional innovative component of liquid-metal technology of atomic engineering. In this paper, we used sodium silicofluoride (Na₂SiF₆), i.e., phosphate Ca(HPO₄)₂ production waste. Fundamentals of a worldwide unique ecologically clean low-temperature technology of Si reduction from Na₂SiF₆ and Si deposition on substrates in a liquid-metal loop in a single process was developed, as well as a gas-phase technology of Si reduction by sodium from gaseous SiF₄ released during thermal dissociation of Na₂SiF₆.     

Effects of some 5-anilino-1,2,4-thiadiazole derivatives onto leukemic cells

Russian Chemical Bulletin - The antileukemic activities of some thiadiazole derivatives in the forms of hydrochlorides and salicylates have been determined. The insertion of salicylate ion in the...     

2-(2-ARYL-2-OXOETHYL)-4H-BENZO-1,4-THIAZIN-3-ONES AS PRODUCTS OF THE REACTION OF 2-AMINOTHIOPHENOL WITH β-AROYLACRYLIC ACIDS

Interaction of 2-aminothiophenol with β-aroylacrylic acids and their dibromo derivatives led to 2-(2-aryl-2-oxoethyl)-4H-benzo-1,4-thiazin-3-ones. The structure of synthesized compounds was confirmed by IR, ¹H, and ¹³C NMR spectra and X-ray analysis.     

Internal rotation in mononitro-n-alkyl radicals

Internal rotation in the C·H₂(CH₂) _n NO₂ (n ≤ 7) type radicals has been studied. 44 potential functions of the internal rotation, V(φ), have been calculated taking advantage of the B3LYP/6-311++(3df,3pd) and MP2/6-311++(3df,3pd) methods. The trends observed in the series of parameters characterizing the internal rotation have been explained in view of the electron clouds conjugation, the inductive effect of the end groups, the gauche effect, and the rotation tops interaction. The coefficients of V(φ) have been shown to depend predominantly on the nearest surrounding of the rotation axis. Based on this, the generalized functions, V _av(φ), have been developed, their coefficients being dependent exclusively on the rotating bond position. Such functions are convenient for molecular modeling applications.