Conditions under which a thermal instability arises in friction

We investigate the one-dimensional, stationary problem of the temperature distribution and rate of plastic deformation in a uniform material under the influence of friction on the surface. The temperature distribution in the material is found by numerically solving the nonlinear heat conduction equation taking into account heat released both at the surface and in the sample interior. We modeled the rate of plastic deformation as a power-law function of temperature. We observed a phenomenon in the solution that might be called a thermal instability wherein stable solution exist only for loads lighter than some critical load. The temperature and plastic deformation distribution have a macroscopic character, and cannot be explained by the formation of a thin, highly deformed surface layer that is usually observed experimentally.Institute of Strength and Materials Research Physics, Russian Academy of Sciences, Siberian Branch. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 23–27, February, 1994.     

Electroinjection analysis. The introduction of a new variant of flow-injection analysis and comparison with electrophoretically-mediated microanalysis

A new method of mixing sample and reagent due to the difference in their electrophoretic mobilities is introduced. Unlike electrophoretically-mediated microanalysis, sample and reagent are injected from the opposite ends of a capillary tube. This method is compared with electrophoretically-mediated microanalysis. Experiments are performed showing the possibilities of this new method.     

Free vibrations of a thin rectangular plate

An asympototic method developed by V.V. Kucherenko and the author is applied to the problem of free vibrations of a thin plate strip in a state of a plane strain. The first few terms of an asymptotic expansion of the natural frequencies are calculated. The results are compared with those obtained by using the classical and refined theories.     

Phase-transfer catalysed ion-radical perfluoroalkylation of thiols

It has been shown that under conditions of phase-transfer catalysis under UV-irradiation perfluoroalkyl iodides react with aliphatic and aromatic thiols in the water-organic solvent media to form alkyl or aryl perfluoroalkyl sulfides in 60–80% yield.     

Resonant generation of even-order harmonics in metal vapors

Generation of the second- and fourth-order harmonics of laser radiation is reported in Mg vapor at the forbidden 3s ²¹ S _o–4s ¹ S _o transition. The conversion efficiency for the second-order harmonics has been measured to be 10^–2% and for the fourth one 10^–8%.     

Abnormal broadening in triplet-to-triplet absorption spectra caused by aromatic solvents

The triplet-triplet absorption spectra of a number of aromatic molecules were shown to be broadened in low temperature matrices formed by aromatic solvents (toluene, 4-isopropylbiphenyl) as compared with those in aliphatic solvents (ethanol, methylcyclohexane, triethylamine). The effect is exponentially dependent on the energy of the upper triplet state of the solute molecule. The phenomenon is discussed in terms of a strong exchange-resonance interaction between the triplet states of solute and solvent.