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Panchenko, M. V.; Terpugova, S. A.; Dokukina, T. A.; Pol’kin, V. V.; Yausheva, E. P.
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9 Citations
We consider the results of 13 years (1998–2010) of studies of the aerosol condensation activity in Tomsk. The longterm behavior of the condensation activity parameter exhibits, in addition to the annual cycle and its second harmonic, a tendency toward slower, ∼6–7year oscillations. The values were maximum in 1998–1999 and 2005–2007. The annual average values were minimum in 2003 and 2008, i.e., in years when intrusions of subtropical air masses from arid regions of Kazakhstan and Central Asia were the most frequent.
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Protasevich, A. E.; Tikhomirov, B. A.
Mathematical expressions for the shape and amplitude of a photoacoustic signal generated due to the multiphoton absorption of Gaussian laser pulses are derived. It was found that the sensitivity of a photoacoustic spectrometer increases in proportion to n^{3/4} when changing from onephoton linear absorption to nonlinear multiphoton absorption, where n is the nonlinearity exponent. Calibration of the photoacoustic spectrometer used in the measurements of multiphoton absorption cross sections is discussed.
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Belov, V. V.; Tarasenkov, M. V.
6 Citations
Three algorithms of the Monte Carlo method for the calculation of the pulse reaction in channels of laser sensing and communication are considered: the local estimation algorithm, double local estimation algorithm, and proposed modified double local estimation algorithm. Results of testing the algorithms and their comparison are shown. For the case of a homogeneous medium, the performances of the algorithms are compared. The comparison shows conditions for which the proposed algorithm has the advantage over the double local estimation algorithm. The contribution of double, triple, and higher multiplicity scattering is estimated. The high contribution of multiple scattering justifies the applicability of the Monte Carlo method for solving such problems.
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Ageev, B. G.; Sapozhnikova, V. A.; Gruzdev, A. N.; Golovatskaya, E. A.; Dukarev, E. A.; Savchuk, D. A.
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In this work, we compare the chronologies of H_{2}O and CO_{2}, and total pressure in the vacuumextracted annual ring disc gas samples of six Scots pine discs in a single region of tree growth; and analyze the results. It is shown that the discs have different annual CO_{2} distributions, the H_{2}O data weakly correlate with precipitation, but the detected cyclicity is common to all the chronologies analyzed.
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Zuev, V. V.; Zueva, N. E.; Korotkova, E. M.; Pavlinsky, A. V.
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The main factors leading to the increase in the intensity of coniferous forests focal drying in southern Siberia since the 1990s are analyzed. It is shown that a significant factor that weakens the resistance of coniferous trees could be longterm ozone depletion due to the permanent presence in the atmosphere of volcanic aerosols caused by frequent Plinian eruptions in the volcano tropical belt with VEI ≥ 4, which exposed southern Siberia to continuous exposure of high doses of shortwave UVB radiation from 1992 to 2012.
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Lukin, V. P.; Botygina, N. N.; Gladkikh, V. A.; Emaleev, O. N.; Konyaev, P. A.; Odintsov, S. L.; Torgaev, A. V.
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1 Citations
Complex measurements of atmospheric turbulence level were carried out with the use of a differential turbulence meter, a wavefront sensor, and ultrasonic weather stations. The refractive index structure constant was measured daily along horizontal optical paths at the Basic Experimental Station of the V.E. Zuev Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences. The comparative analysis of the data received is given.
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Matvienko, G. G.; Romanovskii, O. A.; Kharchenko, O. V.; Yakovlev, S. V.
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1 Citations
Possibilities of using an overtone CO laser in the midIR range for lidar measurements of air humidity and temperature profiles by the differential absorption method have been studied. Wavelengths for lidar measurements of meteorological parameters are selected. Spatially and spectrally resolved lidar signals, as well as random errors of retrieval of profiles of the atmospheric meteorological parameters, have been calculated using the wavelengths.
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Zakharenko, V. S.; Filimonov, A. P.
1 Citations
It is shown that the photochemical activity of titanium dioxide is significantly higher under the action of solar tropospheric radiation when it is not produced by the traditional way, but from the rutile monocrystal. The magnitudes and spectral dependences of the quantum yield of oxygen photoadsorption and carbon dioxide photodesorption for the titanium dioxide produced from a monocrystal are determined. A mechanism of a sharp increase of the titanium dioxide photoadsorption activity in the oxide surface absorption range is proposed.
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Marakasov, D. A.; Rytchkov, D. S.
3 Citations
A method for calculating the moments of the Wigner distribution function is proposed for laser beams having an arbitrary initial shape and propagating in a turbulent atmosphere; the spectrum of the correlation function of fluctuations of the refractive index and the profile of the structural characteristic are supposed to be arbitrary. The main relations for calculating the moments of the Wigner distribution and some parameters of the beam are presented.
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Panchenko, A. N.; Panchenko, N. A.
2 Citations
Laser parameters in He–Ar(Kr, Xe)–F_{2} and He–F_{2} gas mixtures under pumping by runawayelectron preionized diffuse discharge (REP DD) are studied. It is shown that a REP DD is an efficient XeF* and KrF* laser emission source. Lasing on transitions of molecular fluorine in the VUV region (at 157 nm) was obtained for the first time. It is shown that high homogeneity of REP DD allows an increase in the pulse length in rare gas fluorine lasers. Lasing parameters under the REP DD pumping are comparable with those obtained under pumping by commonly used transverse discharges with preionization.
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