Invasion zone modeling using water- and oil-based muds

The hydrodynamic processes of displacement of reservoir fluids in an oil-saturated reservoir in vertical well drilling are studied by numerical simulation accounting for the drilling conditions and the type of mud (water-clay or oil-based). The influence of the hydrodynamic characteristics of the invasion zone on the specific electrical resistance depending on the type of mud is studied. The results of numerical simulations for the interpretation of high-frequency electromagnetic logs were used to construct geoelectric and hydrodynamic models in the reservoirs with different fluid saturations.     

The general class of the vacuum spherically symmetric equations of the general relativity theory

The system of the spherical-symmetric vacuum equations of the General Relativity Theory is considered. The general solution to a problem representing two classes of line elements with arbitrary functions g ₀₀ and g ₂₂ is obtained. The properties of the found solutions are analyzed.     

Thermal stability of alkylbiphenyls in the subcritical,critical, and supercritical states

The kinetics of gas-phase thermal transformations of 4-methyl-, 4,4′-dimethyl-, 4-tert-butyl-, and 4,4′-di-tert-butylbiphenyls was studied over the temperature ranges 813–848, 733–793, 703–763, and 703–763 K, respectively. Competition between cracking and alkyl substituent isomerization at aromatic nuclei of the initial substance and products formed was observed for tert-butylbiphenyls. The kinetic parameters of the overall transformation of alkylbiphenyls (ABPs) were determined. Recommendations for the determination of the critical temperatures of ABPs, their synthesis, processing, and use of articles with structural fragments in molecules identical to those studied in this work were given. It was found experimentally that 2-, 3-, and 4-methylbiphenyls and their mixtures with toluene were thermally unstable over the whole composition range at critical temperatures (600–780 K).     

Superyoung EAS with N e>107. The ?Hadron? experiment

Summary The combined (EAS+EC) ?Hadron? experiment was made at Tien-Shan Station during 1985–1991. A large statistic of gamma-hadron families, combined with EAS, is now analysed. The result of the leader effect disappearance forN _e>10⁷ was reported earlier and at this Conference too. Here we present new results about the existence of Super Young Showers (SYS) with ageS<0.1, containing gamma-hadron families with visible energy ≥10 TeV. Namely, SYS have anomalous soft-energy spectra of particles at gamma-hadron families. These events may be connected with Young Air Showers (YAS) and Narrow Air Showers (NAS). Paper presented at the Special Session on very high-energy cosmic-ray interactions (superfamilies) of the XXIV International Cosmic-Ray Conference, Rome, August 28–September 8, 1995.     

Investigation of primary cosmic rays at energies above 10<Superscript>14</Superscript> eV

A search for sources of primary cosmic rays at energies of 10¹⁴–10¹⁵ eV was performed using the special independent KLARA+Khronotron unit at the Tien Shan Mountain Cosmic Ray Station in a joint experiment of the Lebedev Physics Institute (LPI) and the Central Research Institute for Physics (KFKI). A full data bank of standard events, consisting of 30 million extensive air showers (EASes), was analyzed. Analysis results are presented as maps of the directions of EAS arrival in equatorial coordinates in which the standard deviation of the number of events exceeds a certain value. These could be directions from which neutral primary cosmic particles (e.g., gamma ray photons) arrive from sources of primary cosmic rays. A match is found between separate directions with results, obtained on other stations, and the location of pulsars.     

The possibility of using specific markers of certain types of medicinal plant raw material for the analysis of multicomponent plant teas and phytoteas

Thirteen multicomponent plant teas and phytoteas are studied to determine specific components in the given product. The validity of the chromato-mass-spectrometry method based on markers contained in the plant raw material for the external control of the composition of plant teas, phytoteas, and other phytopreparations is shown.