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Simulation of Modes of Ionosphere Alfven Resonator with High Quality Factors in the Case of Oblique Geomagnetic Field

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Journal of Electromagnetic Analysis and Applications 2012年第5期4卷 192-198页

作者： Volodymyr Grimalsky Svetlana Koshevaya anatoliy kotsarenko Marco A. Cruz Chavez Autonomous University of State Morelos (UAEM) CIICAp Morelos Mexico Center of Geoscience UNAM is Autonomous National University of Mexico (UNAM) Queretaro Mexico

The properties of the ionosphere Alfvén resonator (IAR) in the general case of an oblique geomagnetic field are investigated. The modes at the frequencies f = 0.2 - 10 Hz well localized within the ionosphere are considered, which are important for the lithosphere—ionosphere coupling. An attention is paid to the modes with quite high quality factors , where . A proper selection of calculated eigenfrequencies has been realized. Two independent simulation algorithms have been proposed. The resonant frequencies and the profiles of magnetic field components of the modes have been calculated. The modulation of electron and ion concentrations at the heights 170 - 230 km leads to essential shifting the resonant frequencies.

关键词： Alfvén Resonator Resonant Modes Quality Factors Modulation

Influence of Geological Factor on Indoor Radon Concentrations in Dwelling of Queretaro,Mexico

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Open Journal of Geology 2014年第12期4卷 627-635页

作者： Rocio García Martínez anatoliy kotsarenko Roman Pérez Enriquez Jose Antonio López Cruz Abeyro Svetlana Koshevaya Jesús Efrén Ospina Norena Centro de Ciencias de la Atmósfera Universidad Nacional Autónoma de MéxicoCiudad UniversitariaMéxico CityMéxico Universidad Autónoma del Carmen(UNACAR) Facultad de IngenieríaCiudad del CarmenMéxico Centro de Geociencias Universidad Nacional Autónoma de MéxicoCampus JuriquillaQuerétaroMéxico CIICAp Autonomous University of State Morelos(UAEM)CuernavacaMéxico Programa de Investigación de Cambio Climático Universidad Nacional Autónoma de MéxicoCiudad UniversitariaMéxico CityMéxico

In this study, radon-222 concentrations were measured within 34 houses distributed in the northern, southern, and central areas of the city of Querétaro in 2007. The objective of this study was to establish the spatial distribution of radon with respect to geological faults and its relation to certain environmental variables. For each sampling site, the radon-222 concentration was analyzed as a function of various climate variables, relative humidity, temperature, and atmospheric pressure, in addition to the ventilation of the house and distance of each site from any geological faults in the area. A multivariate statistical technique was used to analyze these variables based on two components. For component 1, the relative humidity and temperature had the greatest weight, 0.677 and 0.492, respectively, while for component 2, the greatest weights corresponded to radon and the temperature with 0.693 and 0.609, respectively. The average radon concentration across the entire sampling period was 38.92 Bq/m3, the minimum detected value was 6.01 Bq/m3?for site 91GAG0607, and the maximum detected value was 225.95 Bq/m3?for site 91CAM20907. This last value is outside the standards permitted by the Environmental Protection Agency of the United Stated, which is 148 Bq/m3?for indoor environments. With respect to geological faults and their relationship to radon-222, the concentrations for the sampling sites had no relationship to the closeness or distance to these faults.

关键词： Indoor Radon Geology Building Characteristics and Seasonal Variations

Detailed Study of Radon Spatial Anomaly in Tlamacas Mountain Area, Volcano Popocatepetl, Mexico

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Open Journal of Geology 2016年第3期6卷 158-164页

作者： Anatolyi kotsarenko Vsevolod Yutsis Vladimir Grimalsky Svetlana Koshevaya Facultad de Ingeniería Universidad Autónoma del Carmen Cd. del Carmen México División de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnológica San Luis Potosí Mexico Centro de Investigación en Ingeniería y Ciencias Aplicadas Universidad Autónoma del Estado de Morelos Cuernavaca México

Results of a soil radon survey accomplished by 2 different methods during 2 different periods in the area of Tlamacas Mountain are presented. The first study, carried out from 15-APR-2010 to 09-MAY-2010 in 30 measurement sites by means of CR39 solid state nuclear detectors, shows 2 active zones with intensive radon emanation with a characteristic dimension of about 300 meters located in the northwestern and western parts of the Mountain. The second survey, made on 05-JUL-2011 in 23 measurement sites with 10 min sampling by a SARAD RTM 1688 Radon/Thoron monitor, in contrast, revealed a sizeable area depleted in radon and 3 active areas of increased radon release in the lateral Mountain sides. These observed phenomena strengthen our assumption about the presence of an active geological structure in Tlamacas Mountain connected with a geodynamical processes in volcano Popocatepetl.

关键词： Radon Tlamacas Mexico Anomaly Popocatepetl Monitoring

Transparency of Cosmic Radio Waves Caused by Seismic and Volcano Activities

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Journal of Electromagnetic Analysis and Applications 2014年第11期6卷 335-341页

作者： S. Koshevaya Yu. kotsarenko J. A. Escobedo A. kotsarenko V. Yutsis CIICAp Autonomous University of State Morelos (UAEM) Cuernavaca Mexico Universidad Autónoma del Carmen Facultad de Ingeniería Ciudad del Carmen Mexico San Luis Potosi Institute of Scientific Research and Technology Applied Geoscience Department San Luis Potosi Mexico

The generation of different waves in the atmosphere and ionosphere caused by seismic and volcano activities has changed the transparency for cosmic radio waves. It is possible to analyze two cases: the first case caused by the atmospheric acoustic wave, which creates a periodic structure of the electron density in the ionosphere. It is shown that the resonant passing of the radio waves takes place, when the length of the acoustic wave is equal to one or a few lengths of the radio wave. The second case produces the electron density decrease in the F-layer of the ionosphere resulting in an increase in the transparency of the ionosphere for cosmic radio waves. The review of these phenomena is provided in this work and both cases have been confirmed experimentally.

关键词： Transparency Plasma Radio Waves

Superheterodyne Amplification for Increase the Working Frequency

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Journal of Electromagnetic Analysis and Applications 2017年第3期9卷 43-52页

作者： Svetlana Koshevaya Vladimir Grimalsky Yuriy kotsarenko Margarita Tecpoyotl Jesus Escobedo Autonomous State University of Morelos Cuernavaca Mexico

The amplification of microwaves in n-GaAs films has been widely studied. On the other hand, using nonlinear parametric effects in microwave, millimeter, and THz ranges has a large potential. In this paper the resonant nonlinear phenomena are investigated in active n-GaAs semiconductor and in films on its base. The phenomena are the nonlinear interactions of space charge waves, including the frequency multiplication and mixing, and the three-wave interaction between two THz electromagnetic waves and a single space charge wave. This three-wave interaction results in the superheterodyne amplification of THz waves. The electron velocity in GaAs is the nonlinear function of an external electric field. If the bias electric field is more E0>Ecrit ≈3KV/cm , it is possible to obtain a negative differential mobility (NDM and space charge waves). The space charge waves have phase velocity of electrons equal to v0=v(E0), E0=V0/Lz , where V0 is the voltage, producing the bias electric field E0?in GaAs film. The superheterodyne amplification and the multiplication of microwaves are very promising for building active sensors in telecommunications system, radiometers, and radio telescopes. The superheterodyne mechanism has an advantage related to decreasing noise because of increasing of frequency in the process of amplification. It is used in the process of amplification of longitudinal space charge waves that in turn causes the transfer of energy from longitudinal wave into transverse one with increasing frequency. This is realized due to parametric coupling of two transverse waves and a single space charge wave in GaAs.

关键词： Space Charge Waves Superheterodyne Amplification

Comparison of Excitation of Acoustic-Electromagnetic Wave in Piezoelecric Crystal and Crystal with Potential of Deformation

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Journal of Electromagnetic Analysis and Applications 2015年第10期7卷 259-264页

作者： S. Koshevaya V. Grimalsky Y. kotsarenko J. Escobedo-Alatorre Autonomous University of Morelos State CIICAp Cuernavaca Mexico

In this article, the comparison of excitation in high frequencies of acoustic-electromagnetic wave in piezoelecric crystal and crystal with potential of deformation GaAs is investigating. Possible mechanisms of coupling different hybrid waves are the piezoeffect and the deformation potential. As a model it is analyzing a film of crystal places between two symmetrical substrates with the other materials without an acoustic contact. This film includes 2D electron gas with a high negative differential conductivity and uniform initial distribution of electrons. The hybrid acoustic-electromagnetic wave and hybrid space charge wave interact. Amplification of space charge wave takes place due to negative differential conductivity in GaAs. This amplification of space charge waves is causing the amplification of acoustic-electromagnetic wave. It is to show that the symmetric modes, emerging as transverse ones, interact more effectively with the space charge waves. Another important result is the following: at the frequencies f ≈ 10 GHz, the excitation efficiency of acoustic-electromagnetic wave with transverse displacement due to piezoeffect is more effective, but at higher frequencies, the deformation potential is dominating.

关键词： Piezoelectric Crystal Deformation Potential Acoustic-Electromagnetic and Space Charge Waves

Explosions and seismic phenomena based on exciting of acoustic-electromagnetic waves

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Natural Science 2012年第8期4卷 652-658页

作者： S. Koshevaya V. Grimalsky G. Urquiza M. Tecpoyotl A. kotsarenko V. Yutsis N. Makarets Center of Geosciences National Autonomous University of Mexico (UNAM) Juriquilla ZP 76230 Qro. Mexico CIICAp Autonomous University of State Morelos (UAEM) Cuernavaca ZP 62209 Mor. Mexico Faculty of Earth Sciences Autonomous University of Nuevo Leon (UANL) Linares ZP 67700 NL Mexico Physical Faculty T. Shevchenko National University Kyiv ZP 01033 Ukraine

During earthquakes and strong underground explosions it is possible to observe two different effects. The first one is connected with the destruction of media, and this causes acoustic and later hybrid acoustic-electromagnetic waves in an epicenter in the atmosphere and in the ionosphere. Another one is connected with cracks in crystals of rocks, which seems more interesting, because it is possible to recognize the natural earthquakes and industrial explosions. In the first effects due to nonlinear elastic modules the acoustic waves move through the lithosphere and transform their spectra from VLF (very low frequencies ~ 1 - 10 kHz) at the depth of about 30 km into the lower part of ELF (extremely low frequencies, ~ 3 Hz - 1 kHz) on the Earth’s surface, then they pass the atmosphere and penetrate into the ionosphere. During the nonlinear acoustic passage through the atmosphere and the ionosphere, the spectrum transforms from ELF into ULF (ultra low frequencies, < 1 Hz) range. In this review article the classification of spectrum and analysis of two cases of the destruction of rocks in the lithosphere is presented. The rocks possess piezoelectric and piezomagnetic properties. In this case the electromagnetic emission is excited by the fracturing in plates of crystals. The difference of emission from piezoelectric and magnetic plates in cases of industrial explosions and natural seismic events including volcanic phenomena gives a possibility to analyze the method of its identification. The consideration is based on the model of the plate of a finite size with an uniformly moving crack.

关键词： Underground Explosion Nonlinear Passing of Acoustic Waves Piezoelectric and Magnetic Plates Difference Between Natural Seismic Volcanic and Industrial Events

Simulation of Waves Processes in Dusty Emission of Volcano

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Open Journal of Geology 2011年第1期1卷 10-16页

作者： V.V. Grimalsky M.A. Cruz Chavez S.V. Koshevaya A. kotsarenko M. Hayakawa R. Pérez Enriquez Autonomous University of Morelos (UAEM) Cuernavaca ZP 62209 Mor. Mexico

A general method of simulation of processes in dusty based on special programs is presented here. It is pos-sible to prepare the modeling of the dusty in volcano like the dust sound waveguides. Dusty is in state of the plasma .Waveguides are formed by the distribution of dusty particles with various masses m = m(x) in trans-verse coordinate. The dust sound waves propagate along the longitudinal z-direction. In the case of contact of dusty plasma with a semi-infinite dielectric, there exists the dust acoustic mode that possesses the negative group velocity (backward wave) in the specified interval of wave numbers. For analysis it is necessary to use the special numerical methods of calculation of the equations with boundary conditions. Simulation of ion sound wave propagation shows a new dispersion between frequency and wave vector. In some region of pa-rameters of dusty the negative dispersion of wave takes place. This means that the phase and group velocities of wave are opposite (negative dispersion). This phenomenon takes place, when the mass of dust particles has the maximum in the center of the waveguide. The negative dispersion caused the instability in dusty, which open the possibility to create a new phenomenon in dusty including the high temperature and the flame.

关键词： Dusty Plasma Dispersion Negative Group Velocity