Laser-induced breakdown threshold and fracture versus the nanostructure of two-phase glass

The radiation hardness and mechanical strength of single-and two-phase glasses are studied for the case when nanosecond laser pulses (λ= 1.06 μm, τ_0.5 ≈ 12.5 ns) are focused inside the material. Laser interferometry is applied to measure the displacement of the free surface, find optical breakage thresholds, and carry out the fractographic analysis of damaged regions. It is shown that breakdown channels and damage regions develop in a nonlinear manner according to optical breakdown mechanisms, changing each other with an increase in the laser energy. The strength of the two-phase glass is found to be more than four times that of the single-phase glass, although their elastic properties differ insignificantly. Such a considerable difference in the hardness of these materials with chemically similar constitutents is attributed to the presence of the double-lattice nanometer-scale structure of the two-phase glass.     

Activation of cells in a cavitation flow

A cavitation flow in an expanding nozzle is numerically simulated. The cavitation activation of cells is studied experimentally.     

The study of exchange coupling in NiFe/Cu/IrMn trilayer structures by MOKE and FMR measurements

The exchange coupling strength of NiFe/Cu/IrMn trilayer films was examined with both a new magneto optical Kerr effect (MOKE) method developed for the exchange coupling field determination and ferromagnetic resonance (FMR) measurements. We found that the value for exchange coupling field obtained by the MOKE technique coincided with FMR result with high accuracy. Other peculiarities of FMR measurements due to interlayer exchange coupling such as angular dependence of resonance field on Cu spacer thickness are also shown in the article.     

Dielectric properties of liquid crystals of the cyano derivative compounds with different fragments in the molecular core

This paper reports on the results of investigations into the influence of variations in the chemical composition of the aromatic core of cyano-containing molecules of liquid crystals on their dielectric properties in the frequency range 1–2000 MHz. It is shown that the dispersion of the longitudinal permittivity is adequately described by the sum of two Debye processes with different weighting factors and relaxation times. The frequency dependence of the transverse permittivity is well approximated by the Debye process with a continuous distribution of relaxation times in a specified range. It is established that the replacement of one benzene ring in the biphenyl core of the 5CB liquid-crystal molecule by a cyclohexane (or bicyclooctane) fragment leads to a considerable decrease in both relaxation times for the longitudinal permittivity, a change in the low-frequency limit of the relaxation time range for the transverse permittivity, and the evolution of the frequency dependence of the dielectric anisotropy.     

A study of solid-state rhodium(III) sulfates

Solid-state rhodium(III) sulfates and their aqueous solutions were examined by IR and electronic absorption spectroscopy, thermogravimetry, X-ray powder diffraction analysis, and ¹⁰³Rh and ¹⁷O NMR spectroscopy. A study of the spontaneous aquation of freshly prepared solutions showed that this process results in an equilibrium between the subsystems of monomeric and oligomeric complexes. It was found that solid-state rhodium(III) sulfates vary in phase composition, basically consisting of dimeric and trimeric complexes.     

Tetrabutylammonium Salts of Ruthenium(II) Nitroso Complexes

The paper describes synthesis of (nBu₄N)₂[RuNOCl₅](I), (nBu₄N)₂[RuNOCl₄OH](II), (nBu₄N)₂×[RuNOCl₄OH]·6H₂O (III), and (nBu₄N)₂[RuNOCl₅]· 2(nBu₄N)₂[RuNOCl₄(H₂O)]·2H₂O (IV). The complexes were studied by IR spectroscopy and powder Xray and crystal Xray analyses. The structures are built up of [RuNOCl₅]^2- (I, IV), [RuNOCl₄OH]^2- (II, III), and [RuNOCl₄(H₂O)]^- (IV) complex anions, (nBu₄N)⁺ cations, and crystal water molecules (III, IV). The substances are moderately soluble in water; highly soluble in polar organic solvents, such as acetone, ethanol, chloroform, methylene chloride; and almost insoluble in carbon tetrachloride and toluene. Under storage in light, the compounds decompose from the surface; in darkness I and II are stable, whereas III and IV can lose part of the crystal water.