Ultrafast magnetization reversal dynamics investigated by time domain imaging

Spatiotemporal magnetization reversal dynamics in a Ni(80)Fe(20) microstructure is studied using ps time scale scanning Kerr microscopy. Time domain images reveal a striking change in the reversal associated with the reduction in switching time when a transverse bias field is applied. Magnetization oscillations subsequent to reversal are observed at two resonance frequencies, which sensitively depend on the bias field strength. The oscillation at f = 2 GHz is caused by the damped precession of M, while the lower frequency approximately 0.8 GHz mode is interpreted in terms of domain wall oscillation.     

Evidence for changing of cosmic ray composition between 10(17) and 10(18) eV from multicomponent measurements

The average mass composition of cosmic rays with primary energies between 10(17) and 10(18) eV has been studied using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum and the muon density as a function of energy. The results show that the composition is changing from a heavy to lighter mix as the energy increases.     

Study on the isomeric ratios of (γ,p) photonuclear reactions with isotopes 40 92 Zr and 74 183 W in the giant dipole resonance region

We have carried out the study on the isomeric ratios in (γ,p) photonuclear reactions with isotopes ₄₀ ⁹² Zr and ₇₄ ¹⁸³ W in the giant dipole resonance (GDR) region. The targets were irradiated with bremsstrahlungs produced by electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, Dubna, Russia. Spectra of the irradiated samples were measured with a spectroscopic system consisting of 8192-channel analyzer CANBERRA and high-energy resolution semiconductor detector CANBERRA. The results were discussed and compared with those of other authors. The text was submitted by the authors in English.     

Time dependence of the inducing signal of the E. coli SOS system under ultraviolet irradiation

On the basis of the analysis of experimental data for relative concentration of the LexA protein, relative concentrations of single stranded DNA are calculated for active and inactive conformation of the RecA protein. Opportunities of further theoretical and experimental investigations are discussed     

q-Deformation of the Virasoro algebra and lattice conformal theories

A natural definition of the q-deformation of the Virasoro and superconformal algebras is suggesteded. New Liealgebraic symmetries describe a lattice version of the continual theory. A close link between the deformation constructed in this paper and the lattice version of the Faddeev-Takhtadjian-Volkov Virasaro algebra is shown. 18 titles. Published inZapiski Nauchnykh Seminarov POMI, Vol. 235, 1900, pp. 217–227.     

Some capabilities of microwave remote sensing of the atmosphere from drifting vehicles

We study the physical conditions for balloon-borne radiometric sounding of the humidity height profile in the 3-mm atmospheric transparency window, an unusual spectral band for such problems, using a balloon drifting in the tropopause. We solve the inverse problem and discuss the accuracy of reconstruction of the humidity profiles. Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 43, No. 3, pp. 207–216, March 2000     

Efficiency of the even-frequency method for estimating the parameters of a three-parameter compound Poisson distribution

Point estimation issues are investigated for the three-parameter family of compound Poisson distributions. Formulas for parameter estimators and their covariance matrix are derived by the even-frequency method; the asymptotic efficiency of the estimators is expressed with an informant in series form. The efficiency of even-frequency estimation is computed and analyzed for the parameter characteristics. __________ Translated from Prikladnaya Matematika i Informatika, No. 25, pp. 99–106, 2007.     

Influence of free surface energy of polymers on formation of their interphase contact with oxyethylated isononylphenol

The interconnection of the surface energy characteristics of polymers in a wide range of acid-base constituents of the free surface energy and their adhesive interaction with adducts of ethylene oxide and isononylphenol was investigated. It was shown that the content of the polar groups in the polymer surface layer and the length of the oxyethylene chain additively influence the wetting ability and the work of adhesion. The peculiarities of the adhesive interaction of high pressure polyethylene with oxyethylated compounds depending on the thermal oxidation of polymer and the acidity parameters of the surface were revealed.     

Alternating copolymerization of ethylene with carbon monoxide on a supported palladium catalyst

The kinetics of the alternating copolymerization of ethylene with carbon monoxide has been studied in the presence of a palladium catalyst immolized on a polymer support in various media (methanol, toluene, heptane). In the case of hydrocarbon solvents, the activity of the supported catalyst is commensurable with the activity of a homogeneous system in methanol. The melting temperature of the resulting copolymer and its molecular mass depend on the solvent nature. The IR reflectance spectra of the active palladium complex and the ethylene-carbon monoxide copolymer are measured.