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We consider sporadic radio emission which precedes recording of geoeffective coronal mass ejections, using the data of broadband
patrol observations of the Sun in the centimeter-, decimeter-, and meter-wave ranges in some periods of the XXIst–XXIIIrd
solar-activity cycles. The total amount of used information instruments covers 339 events and includes the data from the radioastronomical
facility “Zimenki” of the Radiophysical Research Institute and from the world solar service in the radio-frequency range,
as well as the catalogs of coronal mass ejections recorded by the SMM and SOHO/LASCO instruments. On the basis of statistical
analysis, we reveal the regular features in the characteristics of sporadic microwave emissions observed in the twohour interval
before the coronagraph detection of geoeffective coronal mass ejections, which were defined as radio precursors of such coronal
mass ejections. The revealed features in the characteristics of the radio precursors of geoeffective coronal mass ejections
involve the presence of the broadband centimeter–decimeter radio emission for over 10

We discuss the results of studies of natural and artificial small-scale turbulence in the upper ionosphere. The first data
on the spectrum of sizes of irregularities at altitudes 240–340

We present the results of an experimental study of a single-sided multipactor discharge in crossed fields in a rectangular
waveguide of the 3-cm wavelength band. The discharges with the electron drift on the wide wall of the waveguide along and
across the waveguide axis in a standing wave and a traveling wave are studied. It is found that the multipactor discharge
is capable of developing and absorbing radiation intensively, if the microwave field is not uniform, and multiplying electrons
can have only a limited number (20–30) of sequential collisions on the surface intervals between the field nodes. The specific
power absorbed in the discharge amounted to several kilowatts per square centimeter for a microwave field of about 30

We consider all kinds of double and triple collisional interactions of molecules in a gas. Relation of the coefficients of
the virial equation of state to dimer and trimer equilibrium constants is analyzed. The “excluded volume” for water vapor
is estimated quantitatively. The volume is interpreted as an effective volume which is characterized by the range of molecular
repulsive forces and is related to the collisional interaction of free monomers. Empirical data on water vapor in thermodynamic
equilibrium are used for determination of the second and third virial coefficients, which serve for estimating the upper limits
of the dimer and trimer equilibrium constants of water in the temperature range 273–1273

We consider the problem of excitation of cylindrical microstrip antennas with complex-shaped radiators, which are capable
of producing radiation mainly with horizontal polarization. The problem is solved by the method of moments in the spectral
domain by using the piecewise-specified basic functions. The radiating systems under consideration are a rectangular-cylindrical
radiator with a matching coplanar transition and two pairs of coupled loop strip radiators with slots located in the azimuthal
plane. The radiators are excited by a cylindrical microstrip line, and the line, with a delta generator. Coupling of the radiating
system and the microstrip line is achieved. The possibility to produce the horizontally polarized radiation, which is isotropic
in the azimuthal plane, is demonstrated.

Content Type Journal ArticlePages 1-10DOI 10.1007/s11141-012-9331-yAuthors
A. E. Svezhentsev, A.Ya. Usikov Institute of Radiophysics and Electronics of the National Academy of Science of Ukraine, Kharkov, Ukraine

Journal Radiophysics and Quantum ElectronicsOnline ISSN 1573-9120Print ISSN 0033-8443

We report on the results of theoretical studies of the effect of wind waves on fluctuations of acoustic pulsed signals in
the context of low-mode tomography of shallow sea. Results of numerical simulations of the uncertainty function of wideband
pulses propagating along long-distance acoustic paths are also presented.

Content Type Journal ArticlePages 1-11DOI 10.1007/s11141-012-9329-5Authors
M. A. Raevsky, Institute of Applied Physics of the Russian Academy of Sciences, Nizhny Novgorod, RussiaA. I. Khil’ko, Institute of Applied Physics of the Russian Academy of Sciences, Nizhny Novgorod, Russia

Journal Radiophysics and Quantum ElectronicsOnline ISSN 1573-9120Print ISSN 0033-8443

We consider a modification of the resonant “cuvetteless” method for measuring refractive and absorption indices of liquid
dielectrics, which does not require a priori information on the liquid-layer thickness. The results of precision measurements
of the values of the refractive index and the loss tangent of modern liquid dielectrics in millimeter and submillimeter wave
ranges are shown. These materials are supposed to be used for both cooling the elements of high-power gyrotrons (with an output
power of about a megawatt in the continuous mode), in which these liquids directly interact with electromagnetic radiation,
and microwave-energy absorption in various kinds of calorimetric measuring loads and end loads absorbing the entire radiated
power.

Content Type Journal ArticlePages 1-6DOI 10.1007/s11141-012-9324-xAuthors
V. V. Parshin, Institute of Applied Physics of the Russian Academy of Sciences, Nizhny Novgorod, RussiaE. A. Serov, Institute of Applied Physics of the Russian Academy of Sciences, Nizhny Novgorod, Russia

Journal Radiophysics and Quantum ElectronicsOnline ISSN 1573-9120Print ISSN 0033-8443

We describe the main stages of the development of a gyrotron in the sub-terahertz band with a power of several hundreds of
kilowatts, a duration of the output radiation pulses of about 10

We describe a facility for testing the properties of different objects affected by a sequence of highpower pulses of the microwave
electromagnetic field. The facility performance is implemented due to the power level and stability of the single-mode generation
of a free electron maser with an output frequency of 30

Radiation spectra of pulsed quantum cascade lasers operated at about 2.6 and 3.2 THz have been studied using the Fourier-transform
technique. Tuning of the laser radiation frequency by 5.4