Tunneling Relaxation Mechanisms of the Jahn–Teller Complexes in a CaF2:Cr2+ Crystal

JETP Letters - The temperature dependences of attenuation and the velocity of ultrasonic waves at frequencies of 26–158 MHz in a CaF2 fluorite crystal at the substitution of...     

Special Features of Thermal and Stress Hysteresis of B2–R–B19' Martensitic Transformations in Aged [001]-Oriented Ti–50.6 at.% Ni Single Crystals

Russian Physics Journal - Stress-induced and thermal-induced martensitic transformations (MTs) in compression were investigated in [001]-oriented Ti–50.6 at.% Ni single crystals aged at 573 K...     

Oligomeric epoxy binders with controllable molecular characteristics: Shrinkage upon curing

Experimental data and generalized dependences of the effect of molecular characteristics of epoxy diane oligomers (EDOs) and mixtures thereof of various compositions on the value of volume shrinkage are presented. It is established that EDOs and mixtures thereof with a low molecular weight (to 400) and the content of the first fraction over 90 vol % have the highest value of shrinkage by the moment of gel formation, which allows one to obtain polymeric composite materials and adhesive joints with a low level of residual stresses and high physicomechanical characteristics.     

Ultrasonic transducers based on piezoelectric polymer films for operation in air

The paper presents the results of experimental studies of radiating piezoelectric elements made on the basis of self-supported piezoelectric polymer films. The dependences of the sensitivity of these elements on the geometric parameters and frequency are investigated within a frequency band of 10?C70 kHz. A radiating device containing an ensemble of more than 4000 piezoelectric elements is constructed.     

Low-temperature relaxation in the ZnSe : V<Superscript>2+</Superscript> crystal

Low-temperature anomalies in absorption of the fast transverse and longitudinal ultrasonic waves are revealed in a ZnSe crystal lightly doped (5.6 × 10¹⁸ cm^?3) with V²⁺ ions. These anomalies are interpreted as a manifestation of the Jahn-Teller effect. The temperature dependence of the relaxation time of the impurity 3d electrons is established.     

Iron-Alloyed Vanadium Dioxide Analysis Using X-Ray Photoelectron Spectroscopy Technique

Russian Physics Journal - The paper presents the qualitative and quantitative elemental analysis of V0.93Fe0.07O2 compound powder performed by the X-ray photoelectron spectroscopy (XPS) technique....     

Solubility of monazite chemical components in humic acid solutions

The α-factor is a measure of the epithermal neutron flux deviation from the ideal distribution 1/E, where E is neutron energy. It defends on the position of the irradiation channel in reactor. A determination method of the α-factors in irradiation channels of Dalat reactor is presented by fitting the epithermal neutron spectrum obtained from the calculation using MCNP code. The fitting α-values were compared to those by experiment used the “Cd-ratio” method with monitors ¹⁹⁷Au–⁹⁴Zr and ¹⁹⁷Au–⁶⁴Zn. It shows that the α-values calculated from neutron spectra agree well with experimental ones. The difference between both data is about 6%.     

Phase equilibria in ternary polymer blends

The phase states and rheological properties of blends of three polymers??polystyrene, poly(methyl methacrylate), and the styrene-acrylonitrile copolymer??in the common solvent chloroform are studied. The phase diagrams are constructed and the positions of spinodals are determined via the method of turbidity points. The effect of the third polymer on the compatibility of the binary blend obeys Prigogine??s rule; that is, it is determined by the solubility of the added polymer in the first two components. The extremum composition dependence of rheological properties of ternary polymer systems in the vicinity of the separation point (the metastable region) is found. Through the method of convex-shell construction, the phase diagrams are calculated.     

Ultrasonic Determination of the Jahn–Teller Effect Parameters in Impurity-Containing Crystals

Journal of Experimental and Theoretical Physics - A method is developed to determine the symmetry properties of strains and the type of Jahn–Teller effect in crystals with impurity ions in a...     

Determining the Parameters of the Jahn–Teller Effect in Impurity Centers from Ultrasonic Experiments: Application to the ZnSe : Ni2+ Crystal

Physics of the Solid State - The earlier developed methodology of ultrasonic investigation for determining the parameters of the Jahn–Teller effect (JTE) in impurity centers in crystals is...