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  • 11
    Electronic Resource
    Electronic Resource
    New electron energy transfer and cooling rates by excitation of O2 (1998)
    Springer
    Annales geophysicae 16 (1998), S. 1007-1013 
    Details
    ISSN: 0992-7689
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract In this work I present the results of a study of the electron cooling rate, the production rates of vibrationally excited O2, and the production frequency of the O2 vibrational quanta arising from the collisions of electrons with O2 molecules as functions of the electron temperature. The electron energy transfer and cooling rates by vibrational excitation of O2 have been calculated and fitted to analytical expressions by use of the revised vibrationally excited O2 cross sections. These new analytical expressions are available to the researcher for quick reference and accurate computer modeling with a minimum of calculations. It is also shown that the currently accepted rate of electron energy loss associated with rotational transitions in O2 must be decreased by a factor of 13.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00585-998-1007-8
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  • 12
    Electronic Resource
    Electronic Resource
    Subauroral red arcs as a conjugate phenomenon: comparison of OV1-10 satellite data with numerical calculations (1997)
    Springer
    Annales geophysicae 15 (1997), S. 984-998 
    Details
    ISSN: 0992-7689
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract This study compares the OV1-10 satellite measurements of the integral airglow intensities at 630 nm in the SAR arc regions observed in the northern and southern hemisphere as a conjugate phenomenon, with the model results obtained using the time-dependent one-dimensional mathematical model of the Earth ionosphere and plasmasphere (the IZMIRAN model) during the geomagnetic storm of the period 15–17 February 1967. The major enhancements to the IZMIRAN model developed in this study are the inclusion of He+ ions (three major ions: O+ H+ and He+ and three ion temperatures), the updated photochemistry and energy balance equations for ions and electrons, the diffusion of NO+ and O+2 ions and O(1D) and the revised electron cooling rates arising from their collisions with unexcited N2, O2 molecules and N2 molecules at the first vibrational level. The updated model includes the option to use the models of the Boltzmann or non-Boltzmann distributions of vibrationally excited molecular nitrogen. Deviations from the Boltzmann distribution for the first five vibrational levels of N2 were calculated. The calculated distribution is highly non-Boltzmann at vibrational levels v 〉 2 and leads to a decrease in the calculated electron density and integral intensity at 630 nm in the northern and southern hemispheres in comparison with the electron density and integral intensity calculated using the Boltzmann vibrational distribution of N2. It is found that the intensity at 630 nm is very sensitive to the oxygen number densities. Good agreement between the modeled and measured intensities is obtained provided that at all altitudes of the southern hemisphere a reduction of about factor 1.35 in MSIS-86 atomic oxygen densities is included in the IZMIRAN model with the non-Boltzm-ann vibrational distribution of N2. The effect of using of the O(1D) diffusion results in the decrease of 4–6% in the calculated integral intensity of the northern hemisphere and 7–13% in the calculated integral intensity of the southern hemisphere. It is found that the modeled intensities of the southern hemisphere are more sensitive to the assumed values of the rate coefficients of O+(4S) ions with vibrationally excited nitrogen molecules and quenching of O+(2D) by atomic oxygen than the modeled intensities of the northern hemisphere.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00585-997-0984-3
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  • 13
    Electronic Resource
    Electronic Resource
    Mechanisms of the electron density depletion in the SAR arc region (1996)
    Springer
    Annales geophysicae 14 (1996), S. 211-221 
    Details
    ISSN: 0992-7689
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract This study compares the measurements of electron density and temperature and the integral airglow intensity at 630 nm in the SAR arc region and slightly south of this (obtained by the Isis 2 spacecraft during the 18 December 1971 magnetic storm), with the model results obtained using the time dependent one-dimensional mathematical model of the Earth’s ionosphere and plasmasphere. The explicit expression in the third Enskog approximation for the electron thermal conductivity coefficient in the multicomponent mixture of ionized gases and a simplified calculation method for this coefficient presents an opportunity to calculate more exactly the electron temperature and density and 630 nm emission within SAR arc region are used in the model. Collisions between N2 and hot thermal electrons in the SAR arc region produce vibrationally excited nitrogen molecules. It appears that the loss rate of O+(4S) due to reactions with the vibrationally excited nitrogen is enough to explain electron density depression by a factor of two at F-region heights and the topside ionosphere density variations within the SAR arc if the erosion of plasma within geomagnetic field tubes, during the main phase of the geomagnetic storm and subsequent filling of geomagnetic tubes during the recovery phase, are considered. To explain the disagreement by a factor 1.5 between the observed and modeled SAR arc electron densities an additional plasma drift velocity \sim-30 m s−1 in the ion continuity equations is needed during the recovery phase. This additional plasma drift velocity is likely caused by the transition from convecting to corotating flux tubes on the equatorward wall of the trough. The electron densities and temperatures and 630 nm integral intensity at the SAR arc and slightly south of this region as measured for the 18 December 1971 magnetic storm were correctly described by the model without perpendicular electric fields. Within this model framework the effect of the perpendicular electric field \sim100 mv m−1 with a duration \sim1 h on the SAR arc electron density profiles was found to be large. However, this effect is small if \sim1-2 h have passed after the electric field was set equal to zero.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00585-996-0211-7
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  • 14
    Electronic Resource
    Electronic Resource
    The role of vibrationally excited oxygen and nitrogen in the ionosphere during the undisturbed and geomagnetic storm period of 6–12 April 1990 (1998)
    Springer
    Annales geophysicae 16 (1998), S. 589-601 
    Details
    ISSN: 0992-7689
    Keywords: Ion chemistry and composition ; Ionosphere – atmosphere interactions ; Ionospheric disturbances
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract We present a comparison of the observed behavior of the F-region ionosphere over Millstone Hill during the geomagnetically quiet and storm periods of 6–12 April 1990 with numerical model calculations from the IZMIRAN time-dependent mathematical model of the Earth’s ionosphere and plasmasphere. The major enhancement to the IZMIRAN model developed in this study is the use of a new loss rate of O+(4S) ions as a result of new high-temperature flowing afterglow measurements of the rate coefficients K1 and K2 for the reactions of O+(4S) with N2 and O2. The deviations from the Boltzmann distribution for the first five vibrational levels of O2(v) were calculated, and the present study suggests that these deviations are not significant. It was found that the difference between the non-Boltzmann and Boltzmann distribution assumptions of O2(v) and the difference between ion and neutral temperature can lead to an increase of up to about 3% or a decrease of up to about 4% of the calculated NmF2 as a result of a respective increase or a decrease in K2. The IZMIRAN model reproduces major features of the data. We found that the inclusion of vibrationally excited N2(v 〉 0) and O2(v 〉 0) in the calculations improves the agreement between the calculated NmF2 and the data on 6, 9, and 10 April. However, both the daytime and nighttime densities are reproduced by the IZMIRAN model without the vibrationally excited nitrogen and oxygen on 8 and 11 April better than the IZMIRAN model with N2(v 〉 0) and O2(v 〉 0). This could be due to possible uncertainties in model neutral temperature and densities, EUV fluxes, rate coefficients, and the flow of ionization between the ionosphere and plasmasphere, and possible horizontal divergence of the flux of ionization above the station. Our calculations show that the increase in the O+ + N2 rate factor due to N2(v 〉 0) produces a 5–36% decrease in the calculated daytime peak density. The increase in the O+ + O2 loss rate due to vibrationally excited O2 produces 8–46% reductions in NmF2. The effects of vibrationally excited O2 and N2 on Ne and Te are most pronounced during the daytime.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00585-998-0589-5
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  • 15
    Electronic Resource
    Electronic Resource
    Cooling rate of thermal electrons by electron impact excitation of fine structure levels of atomic oxygen (1999)
    Springer
    Annales geophysicae 17 (1999), S. 919-924 
    Details
    ISSN: 0992-7689
    Keywords: Atmospheric composition and structure (thermosphere - composition and density) ; Ionosphere (mid-latitude ionosphere; modelling and forecasting)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The atomic oxygen fine structure cooling rate of thermal electrons based on new effective collision strengths for electron impact excitation of the ground-state 3P fine-structure levels in atomic oxygen have been fitted to an analytical expression which is available to the researcher for quick reference and accurate computer modeling with a minimum of calculations. We found that at the F region altitudes of the ionosphere the new cooling rate is much less than the currently used fine structure cooling rates (up to a factor of 2–4), and this cooling rate is not the dominant electron cooling process in the F region of the ionosphere at middle latitudes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00585-999-0919-2
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  • 16
    Electronic Resource
    Electronic Resource
    Comparison of the measured and modelled electron densities and temperatures in the ionosphere and plasmasphere during 20/30 January, 1993 (2000)
    Springer
    Annales geophysicae 18 (2000), S. 1257-1272 
    Details
    ISSN: 0992-7689
    Keywords: Ionosphere (ionospheric disturbances; ionosphere-magnetosphere interactions; plasma temperature and density)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract We present a comparison of the electron density and temperature behaviour in the ionosphere and plasmasphere measured by the Millstone Hill incoherent-scatter radar and the instruments on board of the EXOS-D satellite with numerical model calculations from a time-dependent mathematical model of the Earth’s ionosphere and plasmasphere during the geomagnetically quiet and storm period on 20/30 January, 1993. We have evaluated the value of the additional heating rate that should be added to the normal photoelectron heating in the electron energy equation in the daytime plasmasphere region above 5000 km along the magnetic field line to explain the high electron temperature measured by the instruments on board of the EXOS-D satellite within the Millstone Hill magnetic field flux tube in the Northern Hemisphere. The additional heating brings the measured and modelled electron temperatures into agreement in the plasmasphere and into very large disagreement in the ionosphere if the classical electron heat flux along magnetic field line is used in the model. A new approach, based on a new effective electron thermal conductivity coefficient along the magnetic field line, is presented to model the electron temperature in the ionosphere and plasmasphere. This new approach leads to a heat flux which is less than that given by the classical Spitzer-Harm theory. The evaluated additional heating of electrons in the plasmasphere and the decrease of the thermal conductivity in the topside ionosphere and the greater part of the plasmasphere found for the first time here allow the model to accurately reproduce the electron temperatures observed by the instruments on board the EXOS-D satellite in the plasmasphere and the Millstone Hill incoherent-scatter radar in the ionosphere. The effects of the daytime additional plasmaspheric heating of electrons on the electron temperature and density are small at the F-region altitudes if the modified electron heat flux is used. The deviations from the Boltzmann distribution for the first five vibrational levels of N2(v) and O2(v) were calculated. The present study suggests that these deviations are not significant at the first vibrational levels of N2 and O2 and the second level of O2, and the calculated distributions of N2(v) and O2(v) are highly non-Boltzmann at vibrational levels v 〉 2. The resulting effect of N2(v 〉 0) and O2(v 〉 0) on NmF2 is the decrease of the calculated daytime NmF2 up to a factor of 1.5. The modelled electron temperature is very sensitive to the electron density, and this decrease in electron density results in the increase of the calculated daytime electron temperature up to about 580 K at the F2 peak altitude giving closer agreement between the measured and modelled electron temperatures. Both the daytime and night-time densities are not reproduced by the model without N2(v 〉 0) and O2(v 〉 0), and inclusion of vibrationally excited N2 and O2 brings the model and data into better agreement.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00585-000-1257-6
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  • 17
    Electronic Resource
    Electronic Resource
    Method of adjusting the basic parameters of a monoatomic beam and correcting its spatial position based on spectral analysis of the radiation from the atoms (1997)
    Springer
    Atomic energy 83 (1997), S. 723-729 
    Details
    ISSN: 1573-8205
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02414109
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  • 18
    Electronic Resource
    Electronic Resource
    Repair processes in the liver and adrenal cortex of rats after an experimental vascular crisis (1978)
    Springer
    Bulletin of experimental biology and medicine 85 (1978), S. 105-108 
    Details
    ISSN: 1573-8221
    Keywords: rat liver and adrenal cortex ; orthostasis ; regeneration ; morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Repair processes in the liver and adrenal cortex of hemiadrenalectomized female rats with an acute disturbance of the circulation resulting from orthostasis were studied by quantitative methods (cytometry, karyometry, nucleolometry, determination of the cell composition and of the nucleo-cytoplasmic and nucleolo-nuclear ratios). Regeneration of the organs studied showed some common features. During the first days after the experiment the number of dying cells in the organs was increased. Meanwhile the number of amitoses and of binuclear cells increased in the liver. By the 15th day in the adrenal and by the 45th day in the liver the cell composition of the organs was stabilized. During the first week after orthostasis mitotic activity of the epithelial cells was increased in both organs. In the later stages regeneration took place at the intracellular level (activation of the nuclear apparatus and hypertrophy of the cytoplasm of the cells).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00801470
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  • 19
    Electronic Resource
    Electronic Resource
    Morphofunctional changes in the thyroid gland in different variants of chronic experimental stress (1993)
    Springer
    Neuroscience and behavioral physiology 23 (1993), S. 352-356 
    Details
    ISSN: 1573-899X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Conclusions 1. The TG increases the secretion of TH into the circulatory bed under the conditions of chronic experimental stress. 2. A decrease in the secretory activity of the TG is observed in the presence of Stressor exhaustion of the organism's adaptive reactions. 3. The pathogenetic features of the experimental adaptation syndrome depend in many respects on the specific characteristics of the methodological approach to its reproduction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01183028
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  • 20
    Electronic Resource
    Electronic Resource
    Effect of electrode processes on transmission coefficient of a flow transducer for an electromagnetic flowmeter (1977)
    Springer
    Measurement techniques 20 (1977), S. 1464-1467 
    Details
    ISSN: 1573-8906
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00824269
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