Vladimir Poponin

Using the photon correlation spectroscopy, slowly damping quasiperiodic oscillations of long-wave density fluctuations were observed for the first time in semidiluted solutions of DNA fragments with the mean length of 25000 base pairs and the concentration above 1 mg/ml. They may be accounted for by the formation of a soft gel type microstructure.

BioSensors: Plasmonics A major goal in biosensor development is the creation and commercialization of a new, molecular, high-data-content diagnostic platform for the detection of biomarkers for individual patient care and personalized disease treatment. The fi eld of plasmonics offers the potential for creating such biosensors. Plasmonic substrate...

We investigate the critical points of the near field intensity. It is shown that there are no local maxima of the intensity outside dielectric surfaces and the only possible critical points are either local minima or saddle points. Using the boundary charge method we investigate numerically the field distribution around star-like sets of prolate sp...

The energy-momentum conservation law is used to investigate the interaction of pulses in the framework of nonlinear electrodynamics with Lorentz-invariant constitutive relations. It is shown that for the pulses of the arbitrary shape the interaction results in phase shift only.

The properties of stimulated coherent scattering of an electromagnetic wave by a relativistic electron beam were studied in the framework of a three-wave approximation for a noncollinear geometry, when the incident and the scattered waves can propagate at arbitrary angles relative to the electron beam direction. The dispersion equation was obtained...

Laser evaporation technique based on infrared CO2 laser emission was applied for obtaining thin films of molecular materials for photovoltaic cells constructing. Thin zinc phthalocyanine and fullerene single layers were sublimated. Photovoltaic behavior of TiO2 monocrystal phthalocyanine based cells was demonstrated. Photoeffects in the single laye...

Low frequency resonance Raman spectra (RRS) (from 50 cm-1 to 800 cm-1) of Langmuir-Blodgett (LB) films from cupper- iron- and cobalt-phthalocyanines (CuPc, FePC and CoPc) have been measured for the first time. Several new lines in the low frequency part of phonon spectra have been identified. The problem of the low frequency Raman lines assignment...

Using the photon correlation spectroscopy, slowly damping quasiperiodic oscillations of long-wave density fluctuations were observed for the first time in semidiluted solutions of DNA fragments with the mean length of 25000 base pairs and the concentration above 1 mg/ml. They may be accounted for by the formation of a soft gel type microstructure.

Using the photon correlation spectroscopy, slowly damping quasiperiodic oscillations of long-wave density fluctuations were observed for the first time in semidiluted solutions of DNA fragments with the mean length of 25000 base pairs and the concentration above 1 mg/ml. They may be accounted for by the formation of a soft gel type microstructure.

Specific features of the lattice Raman spectra (RS) for nucleoside - triphosphates, DNA condensed phase and chicken chromosome were studies for the first time. The RS were obtained at temperatures of 300 and 80 K under excitation by the yellow line (578.2 nm) of the copper-vapor laser. Basing on the conducted analysis of the low-temperature RS for...

A new class of chemical lasers based on electronic transitions of atoms, radicals, or molecules excited via oxidation chain reactions in the presence of catalysts is proposed and discussed. The possibility is considered of using these processes to realize four lasing schemes: directly via transitions of excited intermediate products, in an exchange...

Stimulated coherent scattering of an electromagnetic wave by a relativistic electron beam is investigated in the framework of the three-wave approximation for the case of noncollinear geometry, when both the incident and scattered waves can propagate at an arbitrary angle to the beam direction. A dispersion equation is derived with which the collec...

Calculations are made of the laser radiation intensity in the caustic of an axicon. Calculations are used to develop methods for optimizing the focusing by matching the profiles of axicon focusing elements and the intensity distribution in the initial laser beam cross section. The results are used to determine the dimensions of continuous laser spa...

(For abstract see issue 16, p. 2924, Accession no. A78-38928)

Holographic interferometry was used to study the heating of nitrogen and mixtures of CO2-N2-He at atmospheric pressure in electron-beam-controlled nonself-sustained discharges. Ionization of the discharge gap was carried out using an electron beam with an energy of 180 keV and a current density of 0.2 A/sq cm. The dependence of shock wave velocity...

(Previously cited in issue 14, p. 2354, Accession no. A77-33480)

A numerical analysis is made of a kinetic model of the processes occurring in a pulse CO2 laser excited by a non-self-sustained discharge. It is shown that the results of calculations are in satisfactory agreement with the experimental data in the range of pump powers covering long- and short-pulse regimes. The proposed model is used in the optimiz...

The presently known most perfect designs for the pulsed CO/sub 2/ laser employ a gaseous mixture of nitrogen (N/sub 2/) and carbon dioxide (CO/sub 2/) with a helium (He) additive. The results of a comparison of the effectiveness of addition of H/sub 2/ and He in two operating regimes at atmospheric pressure are presented. The present analysis gives...

(Previously cited in issue 17, p. 2537, Accession no. A75-35996)

We investigate the critical points of the near field intensity in the vicinity of dielectric bodies illuminated by the incident light. It is shown that in the electrostatic approximation there are no local maxima of the intensity outside dielectric surfaces and the only possible critical points are either local minima or saddle points. Using the bo...