Physical Interpretation of the Motion of a Laser Pulse within the Framework of the Four-Oscillator Model

A physical multidimensional local model of the propagation process of a laser pulse in air having no analogy to famous models in laser physics is constructed. It is based on the representations of classical wave mechanics characteristic of the theory of scalar wave fields.     

Evolution of dynamic spiral domains over a period of an alternating magnetic field

The stroboscopic method was applied to study the evolution of dynamic spiral domains in garnet ferrite films in an ac magnetic field. The spiral-domain shape was shown to change significantly within a field period; the basic shape transformations take place in the phase range ?π/4 to +π/4 with respect to the polarity inversion time. During the spiral-domain formation or decay, the area and shape of a hysteresis loop of the film region containing the domain gradually change. The upper boundary of the frequency range in which spiral domains form was established to be associated with transformations of the domain wall structure.     

Synthesis and Steric Structure of Aroxypropynyl Alcohols of the Tetrahydropyran and Tetrahydrothiopyran Series

Optimal conditions have been developed for the synthesis and isolation of phenoxy- and benzyloxypropynyl alcohols of the tetrahydropyran and tetrahydrothiopyran series. The structures of individual isomers have been established on the basis of the ¹H and ^13C NMR spectra. The stereochemical results of the reaction depend on the initial ketone structure.     

Effect of replacing the primary quinone by different species on the ultrafast photosynthetic electron transfer in bacterial reaction centres

Using picosecond absorption spectroscopy it has been shown that in Rhodobacter sphaeroides reaction centres the substitution of the primary quinone acceptor (QA), ubiquinone-10, by other quinone species (with redox potentials higher or lower than that of ubiquinone-10) has essentially no modifying effect on the reaction centre protein. The molecular relaxation processes that accompany the localization and stabilization of a photo-excited electron on the intermediate acceptor, bacteriopheophytin (I), are not affected, although the subsequent transfer of the electron from I to QA is slowed down. Consequently, this leads to a lower quantum efficiency of high rate of direct I-----QA reaction is normally due to the specificity of the primary quinone species and its binding site in the reaction centre protein which provide optimum steric and chemical conditions for an effective interaction between I and QA.     

Synthesis and steric structure of aryloxypropynyl alcohols of the phosphinane series

Phenoxy-and benzyloxypropynyl alcohols of the phosphinane series are synthesized. The steric structure of individual isomers is established by means of ¹H and ¹³C NMR spectroscopy. Stereodirection of the ethynylation of trans- and cis-2,5-dimethyl-1-phenyl-2-thioxo-λ⁵-phosphinane-4-ones is studied.     

The equivalence principle

For the example of the motion of an accelerated charge it is shown that an inertial frame of reference in which there is a homogeneous static gravitational field with strength g is physically inequivalent to a uniformly accelerated frame of reference moving with acceleration-g with respect to the inertial frame of reference. It follows from this that the equivalence principle does not hold in the usual formulation. The widely held opinion that such a principle is the basis of the general theory of relativity is not entirely correct. Einstein's theory of gravitation is based on an equivalence principle of a deeper content, which takes the form that the metric fieldg of a Riemannian space is declared to be a gravitational field. Such is the natural formulation of the equivalence principle at which Einstein subsequently arrived.Institute of High Energy Physics; Serpukhov. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 99, No. 1, pp. 121–140, April, 1994.     

Effect of the polyoxoanion of phosphotungstic acid on the photoconversion efficiency of dye-sensitized solar cells based on titanium dioxide

A method for fabricating form composite photoanodes based on titanium dioxide and phosphotungstic acid has been developed. The introduction of the polyoxometalate into a porous titanium dioxide layer increases the photoconversion efficiency of dye-sensitized solar cells and affects characteristics such as open-circuit voltage and short-circuit current.     

New mechanism of energy release in astrophysical objects

Conclusions The above qualitative analysis of the evolution of astrophysical objects shows that in the field theory of gravitation with minimal coupling objects in the regionM/a<1/3 of values of the mean gravitational potential are stable to small perturbations of their radius with unchanged rest mass.However, the mean gravitational potential of these objects increases when they capture matter surrounding them. When the mean potential reaches the valueM/a=1/3, the object passes abruptly from an infinitely stable state to an infinitely unstable state (with respect to small perturbations of its radius). Therefore, even small perturbations in the radius of the object once the critical value of the mean gravitational potential has been reached necessarily lead to expansion of the matter, which may be accompanied by the ejection of mass of this object and the release of energy.Therefore, instead of gravitational collapse, the outcome of the instability of astrophysical objects in general relativity, in the present theory there is a new mechanism of energy release.Scientific-Research Institute of Nuclear Physics at the Moscow State University. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 48, No. 3, pp. 275–283, September, 1981.