Magnetic resonance in a Cu-Cr-S structure

A layered Cu-Cr-S structure composed of single-crystal CuCrS₂ layers and thin CuCr₂S₄ plates embedded in them has been investigated by the magnetic resonance and scanning electron microscopy methods. The Curie temperature and saturation magnetization of the spinel phase of the investigated samples have been determined. The thickness of the CuCr₂S₄ layers has been estimated. The dependence of the growncrystal topology on synthesis conditions has been established. An interpretation of the anomalous behavior of the magnetostatic oscillation intensity is offered.     

A Silver-Based Electrocontact Material Dispersion-Strengthened with Zinc,Tin, and Titanium Oxides

Technical Physics - A new silver-based electrocontact material dispersion-strengthened with nanopowders of zinc, tin, and titanium oxides has been obtained. The microstructure and elemental...     

Microwave synthesis of hydroxyapatite and physicochemical study of its properties

Method for microwave liquid-phase synthesis of hydroxyapatite samples was developed. The composition of the synthesis products obtained and natural hydroxyapatite was studied by X-ray phase and X-ray fluorescence microanalysis. IR spectra were measured and the dispersity of hydroxyapatite powders obtained, their solubility in water at 20°C, and structural parameters were determined in comparison with natural hydroxyapatite and that produced by the common (“classical”) liquid-phase technique. The microwave-synthesized hydroxyapatite compares well in its properties with the biological and “classical” hydroxyapatites.     

Study of Diffusion Bonding of 45 Steel through the Compacted Nickel Powder Layer

The microstructure of the transition zone and powder spacer, the concentration distribution of chemical elements over the width of the diffusion-bonded joint, and microhardness of 45 steel–compacted Ni powder spacer–45 steel layered composites formed by diffusion bonding have been investigated. It has been shown that the relative spacer thickness χ < 0.06 is optimal for obtaining a high-quality joint has been formed under a compacting pressure of 500 MPa. The solid-state diffusion bonding is accompanied by sintering the nickel powder spacer and the formation of the transition zone between the spacer and steel. The transition zone consists of solid solution of nickel in the α-Fe phase and ordered solid solution of iron in nickel (FeNi₃).     

Study of the microstructure and distribution of elements in diffusion welded joints of tantalum with copper and VT14 titanic alloy

The microstructure of transition areas of welded joints of tantalum with M1 copper and VT14 alloy is investigated. The concentration curve distributions of chemical elements are obtained and the width of transition areas is computed. The coefficients of interdiffusion and the isothermic holding time for obtaining the required width of transition area are computed.     

NMR and the phase transition in hydrated zinc fluotitanate

The NMR spectra of ¹⁹F in polycrystalline zinc fluotitanate ZnTiF₆·6H₂O and ZnTiF₆·6D₂O have been studied between 77 K and room temperature at a frequency of 194.48 MHz. A phase transition at (182 ± 1) K accompanied by large motions of [TiF₆]^2? octahedra was observed. The peculiarity of the NMR spectra above and below the transition is reported.     

Microstructure and properties of a copper electrocontact material with a nanodispersed titanium dioxide additive

The influence of TiO₂ nanopowder additive on the microstructure, physicomechanical properties, and performance characteristics of a copper-based composite is studied. The properties of the composites are compared with those of pure copper compacts. The microstructure and state of the composite’s working surface after performance tests are examined. It is shown that, when the amount of TiO₂ grows, the hardness of the material rises and the arc quenching effect is enhanced.     

Surface Morphology and Structure of Plasma Coatings

Technical Physics - Specific features of the structure formation in rapidly quenched high-cobalt alloy coatings formed by plasma sputtering have been investigated. The structural state of the...     

Magnetooptics and magnetic ordering in ferrite nanoparticles in glass doped with iron and rare-earth elements

Magnetic circular dichroism and X-ray diffraction were used to investigate the structure and magnetooptical properties of nanoparticles formed in potassium-aluminum-germanium-boron glass doped with iron and rare-earth elements. It is demonstrated that in thermally processed glass, the main magnetic phase of the formed nanoparticles is γ-Fe₂O₃ maghemite.     

Fluorine magnetic shielding parameters in the [TiF6]2− octahedral anion

Magnetic shielding tensors of fluorine nuclei in the [TiF₆]²⁻ octahedral anion were measured by¹⁹F NMR. Representative experimental data show them to be independent of the crystal environment of the anion. L. A. Kirenskii Institute of Physics, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 4, pp. 68–75, July–August, 1994. Translated by L. Smolina