Growth kinetics of RF-sputtered nickel films in the beginning stages

By the analysis of X-ray reflectivity angle dependence the existence of a characteristic nucleus height h in the island stage of nickel growth have been found. As the condensation time τ rises, the value of h increases according to a linear law, and the portion of substrate surface occupied by nuclei is described by a curve with saturation. The formation latent period of the fraction with preferential size h is extremely small, that, in principle, allows to produce smooth surfaces, even if the effective thickness is only about several atomic layers. The kinetic characteristics are identical both at growing on monocrystalline silicon and amorphous SiO_x substrates.     

New composite material based on polycarbonate and long-persistent phosphor

Spectral-energy and inertial properties of very long-persistent (> 10 h) phosphor SrAl₂O₄:Eu²⁺, Dy³⁺ were studied using semiconductor light-emitting diodes and other optical radiation sources in the blue and near-ultraviolet regions. The light store accumulated in this phosphor (up to 1 · 10¹⁶ photon/cm²) was estimated and its luminescence kinetics was discussed. The prospects of its application, including phosphor grain introduction into films, were considered.     

The Thermal Decomposition of Magnesium(II) Complexes with Acetic and Halogenacetic Acids

Thermogravimetry (TG), differential thermal analysis (DTA) and other analytical methods have been applied to the investigation of the thermal behaviour and structure of the compounds Mg(Ac)₂ × 2H₂ O(I), Mg(ClAc)₂ ×2H₂ O(II) and Mg(Cl₂ Ac)₂ ×H₂ O(III) (Ac =CH₃ COO⁻ , ClAc =ClCH2COO⁻ , Cl ₂ Ac =Cl₂ CHCOO⁻ ). The solid phased intermediate and resultant products of thermolysis had been identified. The possible scheme of destruction of the complexes is suggested. The halogenacetato magnesium complexes (II–III) are thermally more stable than the acetatomagnesium complex I. The final products of the decomposition of compounds were MgO. Infrared (IR) data suggest to a unidentate coordination of carboxylate ions to magnesium ions in complexes I–III. This revised version was published online in August 2006 with corrections to the Cover Date.     

Optimal Cubature Formulae and Recovery of Fast-Oscillating Functions from an Interpolational Class

The method of limit functions is used to construct optimal-by-accuracy and optimal-by-order (with constant not exceeding two) cubature formulae for the integration of fast oscillatory functions given by their values at a finite number of fixed nodes in a square region. The construction is based on explicit forms of the majorant and minorant in the given interpolational class C _1,L,N ² and the solution of the problem of optimal-by-accuracy recovery of functions from this class. It is shown that an appropriate choice of the grid in this interpolational class leads to a substantial reduction in a priori information required for the application of the proposed approach.This revised version was published online in October 2005 with corrections to the Cover Date.     

Coupled nonlinear effects in modeling field emission from CNTs

Field emission from carbon nanotubes (CNTs) is a complex process involving a range of physical effects and phenomena. In this paper, we systematically develop a multiphysics model to describe this process. We integrate the model numerically to estimate the output current from a CNT based field emission device. Numerical simulations have been able to capture the transients in current as observed in actual experiments. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Dynamics of Explosive Volcano Degassing

We construct a one-dimensional nonstationary model of explosive degassing for a volcano with plugged conduit. The motion of the plug is assumed to be due to the presence of a gas cavity under it into which a gas flows from the underlying magma, which increases the pressure. We show that periodic explosions of gas occur in the system that are separated by long quiescent stages, which agrees with the data of field observations.     

Effect of the nature of the anion on the composition and structure of cobalt complex with monoethanolamine

A number of products formed in reactions of cobalt(II) salts with monoethanolamine (HEtm) in a neutral medium were synthesized and studied. X-Ray diffraction study showed that the nitrate and acetate form the dimers [Co(HEtm)₃][Co(Etm)₃](NO₃)₃ and [Co(HEtm)₃][Co(Etm)₃](CH₃COO)₃ · 8H₂O, respectively. In chloride solutions, cobalt is partially oxidized to give the trinuclear complex [Co^II{Co^III(Etm)₃}₂]Cl₃ · H₂Etm · 2H₂O. The reaction of the chelate [Co(Etm)₃] · 3H₂O with nitric acid is accompanied by complete protonation of the coordinated aminoethanolate ions, and the reaction with formic acid involves complete replacement of the coordinated ligand by acid residue anions and water molecules to give the coordination polymer {Co₂(μ-HCOO)₄(H₂O)₄} _n .