Special and extreme triple shock-wave configurations

Triple shock-wave configurations in steady supersonic flows of an inviscid perfect gas are considered. Triple configurations with special intensities of shock waves and extreme ratios of various flow parameters behind these configurations are determined. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 4, pp. 39–53, July–August, 2006.     

On the application of a single‐crystal κ‐diffractometer and a CCD area detector for studies of thin films

A multipurpose six‐axis κ‐diffractometer, together with the brilliance of the ESRF light source and a CCD area detector, has been explored for studying epitaxial relations and crystallinity in thin film systems. The geometrical flexibility of the six‐axis goniometer allows measurement of a large volume in reciprocal space, providing an in‐depth understanding of sample crystal relationships. By a set of examples of LaAlO₃ thin films deposited by the atomic layer deposition technique, the possibilities of the set‐up are presented. A fast panoramic scan provides determination of the crystal orientation matrices, prior to more thorough inspection of single Bragg nodes. Such information, in addition to a broadening analysis of families of single reflections, is shown to correlate well with the crystallinity, crystallite size, strain and epitaxial relationships in the thin films. The proposed set‐up offers fast and easy sample mounting and alignment, along with crucial information on key features of the thin film structures.     

Study of temperature fields in a rectangular plate with a temperature-dependent internal source with the aid of fast expansions

The approximate analytic solution of the problem of temperature field in a rectangular plate with an internal temperature- dependent source is obtained by the method of fast expansions. The critical value of a parameter characterizing heat release, which fundamentally affects the analytic solution form, is found. The maximum solution error is shown to amount to 0.02 at the consideration of the first three terms of the Fourier series in fast expansion. Temperature fields are presented, and an analysis of the influence of the plate sizes and the heat release magnitude on their formation is given. Recommendations on the plate shape choice are given.     

Differential Characteristics of the Overexpanded Gas Jet Flow Field in the Vicinity of the Nozzle Edge

Technical Physics - A parametric study of the features of the flow field of a plane and axisymmetric overexpanded ideal gas jet in the vicinity of the nozzle edge has been conducted over the entire...     

Analytic description of the domain of existence of triple configurations with a negative slope of reflected shock

We consider triple configurations of compression shocks in supersonic flows of an inviscid perfect gas. The boundaries of the domain of existence of shock-wave structures of a new type (triple configurations with a negative slope of the reflected shock or negative triple configurations) on a set of flow parameters have been theoretically investigated.     

Ion-selective and complexation properties, vibrational spectra, and crystal and molecular structure of 1,5-bis[2-(hydroxyethoxyphosphoryl)phenoxy]-3-oxapentane

The ion-selective properties of 1,5-bis[2-(hydroxyethoxyphosphoryl)phenoxy]-3-oxapentane H₂R² have been described. The molecular and crystal structure of H₂R² has been determined by powder X-ray crystallography and IR spectroscopy. The molecule has the twofold symmetry axis, orthorhombic crystal system, space group Pbcn, a = 16.830(2) ?, b = 8.866(15) ?, c = 15.7190(2) ?, V = 2346.1(6) ?³, Z = 4. A new CuR² · 2H₂O complex has been synthesized and characterized.     

XPS study of the oxidation of nanosize Ni/Si(100) films

The XPS (X-ray photoelectron spectroscopy) study of nickel oxide nanolayers obtained by magnetron sputtering of the metal and its subsequent oxidation in air at different temperatures (400°C and 1000°C) was performed. Silicon(100) was used as a substrate. Surface of the initial Ni/Si structure was shown to contain not only Ni metal, but also the NiO oxide. Annealing at 400°C results in a complete oxidation of the metal film. At a high-temperature annealing (1000°C), nickel interacts both with oxygen and silicon substrate to form NiSi silicide and a composite Ni-Si-O phase in transition layer. Electronconductivity of NiO films is determined by intercrystallite barriers. Activation energies of film electroconductivity in model gases (O₂, Ar, H₂) were found.