Inverse TERS effect in methyl hydroxyethyl cellulose layers

The Raman scattering signal at the second harmonic (532 nm) of cw Nd:YAG laser in a 0.5-μm-thick methyl hydroxyethyl cellulose film on a gold substrate is found to be attenuated when a platinum-iridium probe (with a tip radius of about 10 nm) of a scanning tunnel microscope is brought close (at a distance of 6 to 8 nm) to the surface. The fluorescence signal barely changes under these conditions.     

On the inequality of partial temperatures of a homogeneous gas mixture in the thermodynamic equilibrium state

A modified definition of the state of thermodynamic equilibrium of a homogeneous multicomponent gas mixture is given. It is based on the discrete character of collisions but not on the smoothed-by-multiple-collisions dynamic structure with the physical determination of the kinetic time dt. Application of rigorous mathematical methods which adequately describe the discrete character of collisions leads to a qualitatively new structure of the distribution functions and unexpected physical consequences. It is shown that owing to the inequality of head-on and head-tail collisions of particles, partial temperatures of a homogeneous multicomponent gas mixture in thermodynamic equilibrium cannot be equal to each other. It is found that relations of the partial temperatures to the mixture temperature are dependent on the molecular weights and concentrations of the gas components.     

Positive definiteness of the gravitational radiation intensity in the theory of gravity with a nonzero graviton mass

A version of the theory of gravity is considered where the graviton mass is nonzero, and the gravitation radiation flux from an arbitrary spatially-bounded source is positive definite. The relation between energy losses by emission and the work of the source is established. It is shown that the total work includes the part produced by the interaction of the source with the radiation field and the part produced by the self-action of the field. The total work proves to be positive definite. The general form of the spectrum-angular distribution is obtained, accounting for the spin and polarization states. For spherically symmetric sources, the states with zero spin and zero projection of spin two on the momentum contribute to the emission.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 107, No. 2, pp. 329–343, May, 1996.Translated by V. I. Serdobol'skii.     

New approach to the defibrillation problem: Suppression of the spiral wave activity of cardiac tissue

A model of an excitable medium is considered for describing the development of fibrillation (i.e., spatiotemporal chaos) in cardiac tissue through the generation of a set of coexisting spiral waves. It is shown that a weak external point action on such a medium leads to the suppression of all spiral waves and, correspondingly, to the stabilization of the system dynamics. After reaching the regular regime, only the external source exists in the medium. The frequencies and amplitudes at which such stabilization occurs are determined. The case of the action of several point sources is considered. Analysis is performed using the Bray method to identify the number of spiral waves.     

An unexpected skeletal transformation of 1,4-dihydroxythioxanthen-9-one on treatment with iodic acid: the first construction of the 2-(5-oxofuran-2-ylidene)-1-benzothienyl-3-one core

Treatment of 1,4-dihydroxythioxanthen-9-one with iodic acid gives, depending on the reaction conditions, predominantly either thioxanthen-1,4,9-trione or, unexpectedly, 2-(5-oxofuran-2(5H)-yliden)-1-benzothienyl-3(2H)-one. The latter is obtained in 60% yield.