Effective area of the antenna of the RT-22 CrAO RI radio telescope

Based on the results of calibrator observations at 13.5-mm and 8.2-mm wavelengths in 1985 and 2005, the dependence of the effective area of the RT-22 CrAO RI antenna on ambient temperature and elevation was determined. The obtained results confirm a high quality of the RT-22 antenna at millimeter wavelengths. A high accuracy of the reflector surface makes it possible to observe at millimeter wavelengths right to 2 mm. At 8.2-mm wavelength, the effective area changes by no more than 5% when the antenna is reinstalled from the zenith to 15° elevation angle. Large antennas, intended to operate at maximum frequencies, should be built either taking into account the climatic conditions of the antenna sites or taking measures to provide thermal stability of the antenna.     

The relationship between the wind and waves in the North Atlantic and atmospheric circulation oscillations

Characteristics of wind and waves are computed using the data of instrumental observations on the moored buoys in the northeastern part of the North Atlantic during the cold periods (November–March) of 2009–2013. Their comparison is carried out for different phases of the North Atlantic and East Atlantic oscillations and for the combinations of these phases.     

Studies of the quasar OH 471

Based on the 1964–1996 observations in the frequency range 0.325–90 GHz, we study peculiarities of the variability of the quasar OH 471 (z=3.4). The double-humped spectrum had peaks at frequencies near 1 and 20 GHz. The flux density of the low-frequency component first decreased and then began to increase. The high-frequency component rose to 2.5 Jy in the late 1970s. The peak frequencies were virtually constant. VLBI observations at 1.6 GHz revealed a core-jet structure with the jet extended eastward to 5 mas. The object is a powerful quasar.     

Ionospheric perturbation indices based on the low- and high-orbiting satellite radio tomography data

GPS Solutions - Methods are suggested for constructing ionospheric perturbation indices (IPIs) based on empirical radio tomographic (RT) electron density distributions taking into account...     

First Findings of Trace Fossils from the Tavda Formation (Middle–Upper Eocene) in the Southwestern Part of Western Siberia

Trace fossils have been found for the first time in the Tavda Formation shallow marine facies, and their possible indicative value has been evaluated. The results of the ichnofossil study suggest that the Tavda Basin had low hydrodynamics. Under these conditions boreal and thetic waters of different characteristics were blended, which caused periodic formation of thermohaline water stratification and anoxic conditions in bottom water levels. Such periodic events conditioned mass extinctions of a wide variety of the Eocene marine biota thus preconditioning the development of freshwater fauna in the upper levels of the Tavda Sea along with saturation of the index beds of the Tavda Formation with micro- and macrofossils.     

Observations of extragalactic radio sources at 36 GHz

The observations of 34 extragalactic radio sources with the 22-m Crimean Astrophysical Observatory radio telescope at 36 GHz in 1985–1994 are presented. Intensity variations were detected in 27 objects, which may result from the appearance of new components in their cores.     

Influence of the surface water temperature and heat flux in the North Atlantic on the atmospheric circulation

Correlation of water temperature and latent heat fluxes in winter in the North Atlantic with the atmospheric circulation in the subsequent months are analyzed based on the NCEP/NCAR reanalysis data. Monthly and daily indices of the North Atlantic Oscillation are used as characteristics of the atmosphere circulation. It is shown that conditions of the heat exchange between ocean and atmosphere in the western North Atlantic in February can influence the atmospheric circulation and air temperature in Europe in March.     

Magnetic field of solar prominences: The procedure of radio observations

The first successful radio astronomical results of measurements of the magnetic field of solar prominences are presented. The accuracy of polarization and magnetic field observations is 3 · · 10⁻⁴ and 2 G, respectively. The observations were made by the 22-meter radio telescope of the Crimean Astrophysical Observatory at wavelengths of 8 and 13.5 mm. It has been found that the value of the magnetic fields coincides with the optical one (from 7 to 30 G), but the image of radio polarization differs from the intensity.     

Microbial enhanced oil recovery—a modeling study of the potential of spore-forming bacteria

Microbial enhanced oil recovery (MEOR) utilizes microbes for enhancing the recovery by several mechanisms, among which the most studied are the following: (1) reduction of oil-water interfacial tension (IFT) by the produced biosurfactant and (2) selective plugging by microbes and metabolic products. One of the ways of bacterial survival and propagation under harsh reservoir conditions is formation of spores. A model has been developed that accounts for bacterial growth, substrate consumption, surfactant production, attachment/filtering out, sporulation, and reactivation. Application of spore-forming bacteria is an advantageous novelty of the present approach. The mathematical setup is a set of 1D transport equations involving reactions and attachment. Characteristic sigmoidal curves are used to describe sporulation and reactivation in response to substrate concentrations. The role of surfactant is modification of the relative permeabilities by decreasing the interfacial tension. Attachment of bacteria reduces the pore space available for flow, i.e., the effective porosity and permeability. Clogging of specific areas may occur. An extensive study of the MEOR on the basis of the developed model has resulted in the following conclusions. In order to obtain sufficient local concentrations of surfactant, substantial amounts of substrate should be supplied; however, massive growth of bacteria increases the risk for clogging at the well inlet areas, causing injectivity loss. In such areas, starvation may cause sporulation, reducing the risk of clogging. Substrate released during sporulation can be utilized by attached vegetative bacteria and they will continue growing and producing surfactant, which prolongs the effect of the injected substrate. The simulation scenarios show that application of the spore-forming bacteria gives a higher total production of surfactant and the reduced risk of clogging, leading to an increased period of production and a higher oil recovery.     

Oil and gas pools: the fundamentals of formation,prospecting, and exploitation

The paper deals with the main fundamental problem of oil and gas geology—compilation of a theoretical basis and elucidation of the mechanism of hydrocarbon pool formation. The temperature factor determining this mechanism is insufficient for the breaking of carbon–carbon bonds in organic molecules. It is shown that this process is provoked by the internal energy of the subsurface organic matter determined by unpaired electrons surrounding carbon nuclei. In natural processes, this phenomenon is realized as a result of sedimentary-rock consolidation on the subsidence of sedimentation basins, during subhorizontal microdislocations measured via Poisson's ratio and Protod'yakonov “arch”. This effect can be reached on hydrofracturing. A possibility of fluid hydrocarbon migration beyond the modern-day oil and gas pools is discussed, thus demonstrating that there are no traces that would suggest oil migration. Hydrocarbon pools have been revealed in clayey rocks, both bituminous and OM-poor. It is shown that the exploitation of a new type of reservoir (bazhenite) with natural hydrocarbon pools as well as technogenic (newly formed) oil and gas pools in clayey, clay-siliceous, siliceous, clay-carbonate, and clay-siliceous-carbonate bituminous rocks will significantly increase oil production in West Siberia.