Monitoring environmental electromagnetic fields. 1. Remote-sensing methods

This paper discusses monitoring electromagnetic fields (natural and artificial) in the atmosphere. Methods are described for remote sensing of the atmosphere and surface in order to examine static and alternating electromagnetic-energy fluxes in the biosphere.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 69–79, December, 1991.     

Monitoring of electromagnetic fields in the environment. II. Fluctuations in the parameters of atmospheric electricity

The problems of determining and investigating the informative parameters of atmospheric electricity are discussed. It is shown that short-period variations in atmospheric electricity are ecologically significant. An automated system for monitoring atmospheric electricity and a method of processing the results of measurements are described. V. D. Kuznetsov Siberian Physicotechnical Institute, Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 88–98, May, 1998.     

Electrical Conductivity in a Laser Beam Channel

Russian Physics Journal - Electrical conductivity in a laser beam channel has been investigated. Oscillations of the conductivity caused by the oscillation motion of electrons in laser-induced...     

Investigation of time characteristics of photodetectors based on Ge/Si nanoheterostructures

Results of investigations into the time characteristics of photosensitive layers based on Ge/Si nanoheterostructures excited by femtosecond laser pulses with a wavelength of 1.55 μm are given. It is demonstrated that the leading front duration of the photoresponse pulse for the examined specimens excited by laser pulses of 120 fs duration does not exceed 30–40 пs.     

Influence of scattering on superluminescence in composites dye solution – nanoparticles

Spectral and energy luminescence characteristics of R6G dye solutions in ethanol with addition of Ag nanoparticle suspensions in different aggregate states are experimentally investigated. It is demonstrated that incorporation of non-aggregated and aggregated nanoparticles causes the superluminescence thresholds in R6G solutions to decrease. It is established that the optical properties of the laser beam propagation channel are transformed when low-power (20 mW) cw laser radiation passes through the suspension of nanoparticles. This is manifested through the occurrence of a region with enhanced nanoparticle density in the laser beam center, on which diffraction of laser radiation is observed.     

Experimental investigation of attenuation and backscatter of laser radiation at λ=2.36 μ and λ=0.63 μ by artificial fogs and smokes

The attenuation and backscattering of laser radiation at X = 2.36 and A = 0.63 by artificial fogs and smokes is investigated experimentally. The relationship between the absorption coefficients for these wavelengths is expressed by the linear dependence (2.36) = K (0.63). For fogs with the most probable microphysical parameters K = 1.18, while for smokes, K =0.4. It is shown experimentally that the geometrical parameters of the experimental setup and the optical properties of the scattering medium have a greater effect on the intensity of backscattered radiation than does the wavelength of the incident radiation.Translated from Izvestiya VUZ. Fizika, No. 6, pp. 62–67, June, 1973.     

Reflection of narrow light beams by a dissipating medium

The brightness distribution of multiple back-scattering of radiation is investigated in a plane perpendicular to the beam axis as a function of the density of the artificial mists and smokes. The range of the distances from the beam axis (base) investigated was 0.02–1 m or 10^–4–1.8 in optical quantities. The investigations were accompanied by parallel measurements of the scattering index by using a turbidimeter, which permitted making quantitative estimates of the influence of the form of the index on the magnitude of the intensity of the multiply-scattered radiation for diverse values of the optical base. It is shown that the brightness distribution of the multiply scattered radiation takes on a smoother shape as the elongation of the index increases.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 61–65, November, 1973.