Peculiarities of Monitoring the State of a Flowing Medium by the Method of Nuclear Magnetic Resonance

Technical Physics Letters - Specific features of monitoring the state of a flowing medium by method of nuclear magnetic resonance (NMR) are considered. An approach to studying the state of a...     

Effect of tempering temperature on the wear resistance and corrosive properties of nitrogen-bearing austenite-martensite steel 08Kh14AN4MDB

The effect of tempering temperature on the structure, wear resistance, and corrosive properties of steel 08Kh14AN4MDB is studied. The results of mechanical and corrosion tests are used for constructing an optimization matrix for determining the optimum tempering temperature. __________ Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 29–32, February, 2007.     

Determination of the parameters of phosphor activators in thin-film electroluminescent capacitor structures

A method for determining the concentration and electron-impact excitation cross section of activated emission centers in the phosphor layer of a thin-film electroluminescent capacitor structure, based on measurements of the brightness as a function of the applied alternating voltage amplitude and frequency, is analyzed. The error of determination of the parameters of electroluminescence excited by alternating-sign ramp voltage is evaluated. The parameters of electroluminescent structures based on the ZnS:Mn, ZnS:TbF₃, and ZnS:SmF₃ films are presented.     

Electrical characteristics of (<Emphasis Type="Italic">p</Emphasis>)3C-SiC-(<Emphasis Type="Italic">n</Emphasis>)6H-SiC heterojunctions

The electrical characteristics of (p)3C-SiC-(n)6H-SiC epitaxial heterostructures obtained by sublimation epitaxy in vacuum are studied. The band discontinuities are determined and the energy band diagram of the heterojunction is constructed. It is shown that the obtained heterostructure offers a promising material for high electron mobility transistors.     

Oxidative radical generation via nitrogen dioxide dimer conversions induced by amide groups of macromolecules

The features of initiation of free radical reactions in polymers by dimers of nitrogen dioxide are considered. The conversion of planar dimers into nitrosyl nitrate in the presence of amide groups of macromolecules has been revealed. Nitrosyl nitrate initiates radical reactions in oxidative primary process of electron transfer with formation of intermediate radical cations and nitric oxide. As a result of subsequent reactions, nitrogen‐containing radicals are produced. The dimer conversion has been exhibited by estimation of the oxyaminoxyl radical yield in characteristic reaction of p‐benzoquinone with nitrogen dioxide on addition of aromatic polyamide and polyvinylpyrrolidone to reacting system. The isomerization of planar dimers is efficient in their complexes with amide groups, as confirmed by ab initio calculations. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Effect of spontaneous polarization on the energy levels in quantum wells formed at the contact between cubic and noncubic silicon carbide polytypes

We have studied the effect of spontaneous polarization, which is inherent in noncubic silicon carbide (SiC) polytypes, on the characteristics of quantum wells (QWs) formed in the cubic region at the heterojunction. The analysis is performed for various QW models, including triangular, parabolic, and exponential. Conditions for the appearance of a two-dimensional electron gas at the interface are briefly discussed.     

Investigation of the parameters of deep centers in n-6HSiC epitaxial layers obtained by gas-phase epitaxy

Epitaxial layers of 6H-SiC obtained by gas-phase epitaxy have been investigated by capacitance spectroscopy methods. It is shown that deep centers are present in the test samples. Such centers were previously observed in SiC epitaxial layers obtained by sublimation epitaxy. However, the total density of deep acceptors in structures prepared by gas-phase epitaxy is two to three orders of magnitude lower than in epitaxial films obtained by sublimation epitaxy with the same value of N _d -N _a . It is suggested that the conditions of growth of the epitaxial layers influence the density and the type of defects formed in them. Fiz. Tekh. Poluprovodn. 31, 1049–1051 (September 1997)