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When mining coal, detailed geological information on the structure of the coal-bearing strata and the quality of coal seams minimizes the risks associated with complicating mining and geological factors and changes in coal quality characteristics. The experience of using the mechanical logging method as an express method of operational exploration at the Olon-Shibirsk coal deposit is considered. Mechanical logging data were compared with core sampling and well logging data. As a result, the criteria for dividing the coal-bearing strata of the deposit into lithotypes were identified. According to these criteria, a general pattern can be distinguished for the considered coal-bearing strata: with a decrease in the dimension of the grains that make up the rock the drilling speed increases; with an increase in the content of organic matter in the rock, the drilling speed also increases and the maximum drilling speed characterizes coal seams. Drilling speed is a defining parameter, while other drilling parameters supplement its readings in case of ambiguity when interpreting the graph. For coal seams, the dependence of the drilling speed on the ash content of the seam was determined. At the same time, the dependence is most precise for seams with a thickness of more than 1 m. Based on the data of operational exploration using mechanical logging the morphology of coal seams and the complexity of their structure and ash content have been clarified for some areas, making it possible to clarify the reserves and quality for geological blocks. The final comparison confirmed the increase in the counting accuracy using the mechanical logging method. The practical significance of the research lies in improving the quality of operational exploration in the deposit while reducing costs. [ABSTRACT FROM AUTHOR]

The reaction of pentafluoroethyllithium with BH3·thf yields [C2F5BH3]− that is stable against H2O, OH− and air due to the electron withdrawing C2F5 group. M[C2F5BH3] (M = K, Cs) are shock sensitive solids whereas salts with organic cations such as the room temperature ionic liquid [EMIm][C2F5BH3] are stable for years. [C2F5BH3]− is a mild reducing agent, which is also reflected by its electrochemical properties. Oxidation with I2 or Br2 in the presence of Lewis bases yields the first stable adducts C2F5BH2·L. [ABSTRACT FROM AUTHOR]

A new version of the discrete ordinate method for the calculation of the transfer of monochromatic radiation in a scattering, absorbing, and emitting plane-parallel atmosphere of Earth and other planets is proposed. A feature of this version is that the system of linear equations obtained by the discrete ordinate method is solved using the block elimination method. This is an exact and computationally efficient method; moreover it is easy to implement. The computer program developed based on this method is about two times faster than the program used in the free DISORT package. [ABSTRACT FROM AUTHOR]

We consider the computations of generalized parameters in a heterogeneous feature space with the 'object-property' table. We use data mining methods for these computations. [ABSTRACT FROM AUTHOR]