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A. Yu. Prokhorov

Publications and source records attributed to A. Yu. Prokhorov.

4 recordsLinked to original sources

Low- and high-temperature anomalies in the physical properties of solid methane

Near 20.48K and in the temperature range 60--70K, anomalous behavior of thermodynamic, spectral, plastic, elastic and other properties of solid methane is observed. The anomalies in the vicinity of 20.48K are due to the phase $α-β$ transition. Anomalies in a relatively wide range of 60--70K are shown to be related to the essentially quantum nature of the collective rotation of methane molecules. The provided analysis of the high-temperature anomalies encompasses a more extensive set of phenomena in comparison with the low-temperature ones. Key words: solid methane, anomalies of physical properties, phase transition, rotational temperature, quantum-classical transition.

cond-mat.mtrl-sci

Low-frequency internal friction (LFIF) as express-method for identification of cryocrystals in pores of the solids

We show that studying of low-frequency internal friction (LFIF) of solid samples at low temperatures allows determining the presence of various gases absorbed, for some reasons, in pores and caverns of the solids. The gases come over to a solid state (cryocrystals) and exist in the pores under corresponding thermodynamic conditions giving an additional contribution to the LFIF spectra. The spectra reflect the special points of the gases (temperatures of melting or phase transitions). This information gives a real opportunity for identification of gas in the matrix, i.e. the studied solids. This may be of great importance for investigations of cosmic or geological samples, for instance, asteroids, meteorites, rock formations, etc. The LFIF method allows identification of gas media surrounding the studied sample.

cond-mat.mtrl-sci

Abnormal behavior of crystalline methane in temperature interval $60-70~K$. From experiment to theory

The paper presents an analysis of mechanical, structural, thermophysical and spectral properties of solid methane in temperature interval $0.5T_{tr} -T_{tr}$ ($T_{tr}$ is the triple point temperature) under equilibrium vapor pressure. It is shown that the anomalies of the studied properties at temperatures 60--70~K have been observed in the body of the reviewed papers. A concept of "topons" (collective excitations of rotational degrees of freedom in solid methane) is proposed. A whole of the observed anomalies can be explained in the frames of this concept. Key words: solid methane, quantum crystals, rotational degrees of freedom, thermophysical and mechanical properties of the crystals

cond-mat.mtrl-sci

Selected aspects of the condensed matter physics. Work and life of Professor B.Ya. Sukharevsky

The paper contains a short description of the scientific papers of Professor Boris Ya. Sukharevsky on condensed matter physics. His basic scientific activity was related to following directions: structural vacancies concept; influence of point defects on statics and kinetics of phase transitions; DNA crystallization and low-dimensional systems properties; phase transitions in Jahn-Teller crystals; Thermophysics of superconductors e.a. The list of most essential papers of Prof. B.Ya. Sukharevsky is included.

cond-mat.mtrl-sci