Structure studies on porous titanium nickelide made by high-temperature self-propagating synthesis

Structure studies are reported on martensite transformations in porous TiNi alloy made by high-temperatures self-propagating synthesis. The transformations occur over a large temperature range and are incomplete. The structure data are used in reconstructing the heat release during the transition, where it is shown that it is determined by the superposition of martensite transformations occurring locally at various temperatures. Tomsk State Architectural and Building Academy. Kuznetsov Siberian Technical Physics Institute, Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 20–24, January, 1997.     

Fast electrons generation by RF and random fields near the antenna I. One dimensional model and regular fields

Test particle motion and acceleration has been explored in strong radio frequency (RF) fields, for which quasilinear ponderomotive force approximation is not valid. By nonlinear acceleration in spatially varying wave amplitude of RF travelling wave, electrons may be accelerated to time averaged velocities significantly larger than the RF wave phase velocity, and than the boundary plasma thermal velocity, in RF fields of several Volts per centimeter at wave frequency of 7 MHz. It is also demonstrated that even weak spatial gradients, much weaker than those expected in experiments, of the RF wave field amplitude, have significant consequences for the particle motion. Estimates are presented of the total energy transferred from the near antenna RF field to the plasma due to the nonlinear electron acceleration effects.     

Excitation of metal spectra in combined glow discharge

Consideration is given to the special features of the excitation of spectra of metals (Ag, Au, Fe, Hg, Pt, and Sb) that manifest themselves in investigating spectral sources with combined glow discharge (glow discharge and capillary discharge). It is established that the proposed method for introducing a substance into a plasma makes it possible to realize two fundamentally different regimes: without evaporation and with complete evaporation and matrix atomization. It is shown that a spectral source of combined glow discharge with a nonequilibrium plasma has significant advantages for the most important analytical characteristics over quasi-equilibrium combined discharge at atmospheric pressure. The gold and platinum sensitivity in combined glow discharge is 10⁻⁷%, and the reproducibility of spectral determinations is 0.001–0.100, depending on the measurement range. A fractional separation of elements that makes it possible to analyze the phase composition of substances, particularly metals, with high sensitivity is revealed in glow discharge. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 2, pp. 143–147, March–April, 1997.     

Transient radiation of acoustic waves at the atmosphere-earth interface

Using the contour integration method, we solved the problem on the transient radiation of acoustic waves by a mass-production source which moves uniformly in a gas in the direction normal to the interface of homogeneous gaseous and elastic half-spaces and vanishes at the moment of the solid surface contact. Asymptotic formulas are derived for the transient radiation field which are valid at the fronts of spherical and lateral waves. An exact analytical expression is obtained for the transient radiation field at observation points in the source trajectory. The total internal reflection effects in the transient radiation of sound are analyzed. Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 40, No. 4, pp. 420–431, April, 1997.     

Relativistic four-quark equations and exotic mesons

The relativistic four-quark equations are found in the framework of the dispersion relation technique. The behaviour of the low-energy four-particle amplitude is determined by its leading singularities in the pair invariant masses. The approximate solutions of these equations using the method based on the extraction of leading singularities of the amplitudes are obtained. The mass values of lowest exotic mesons are calculated.     

On a New Non-Geometric Element in Gravity

In this essay a generalized notion of flavor-oscillation clocks is introduced. The generalization contains the element that various superimposed mass eigenstates may have different relative orientation of the component of their spin with respect to the rotational axis of the gravitational source. It is found that these quantum mechanical clocks do not always redshift identically when moved from the gravitational environment of a non-rotating source to the field of a rotating source. The non-geometric contributions to the redshifts may be interpreted as quantum mechanically induced fluctuations over a geometric structure of space-time.     

Universal elementary constituents of potential transformations shifting waves (qualitative theory)

It is shown that the potential perturbation that shifts a chosen standing wave in space is a block of potential barrier and well for every wave bump between neighbouring knots. The algorithms shifting the range of the primary localization of a chosen bound state in a potential well of finite width are as well applicable to the scattering functions if states of the continuous spectrum are considered as bound states normalized to unity but distributed on an infinite interval with vanishing density. The potential perturbations of the same type on the half-axis concentrate the scattering wave at the origin, thus creating a bound state embedded into the continuous spectrum (zero width resonance).     

Generation of mesoscopic magnetic structures by local laser action

New effects are observed wherein the internal structure of the domain walls in a thin magnetic iron garnet film are modified by the action of focused laser radiation. A single laser pulse with increasing power gives rise to the following: 1) displacement of vertical Bloch lines in a domain wall; 2) generation of a pair of vertical Bloch lines on initially line-free walls; and, 3) an irreversible change in shape of a domain wall and the domain structure as a whole. The mechanism leading to the generation and displacement of Bloch lines is connected with the motion of domain walls which is induced by a local change in the distribution of demagnetizing fields as a result of a heating-induced decrease of the magnetization in the focal spot of the laser radiation. Pis’ma Zh. éksp. Teor. Fiz. 66, No. 6, 398–402 (25 September 1997)