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The basic software package of a JXA-8230 microanalyzer, like its predecessor JXA-8100, uses the long-established ZAF correction method (with some differences) for a quantitative analysis: Calculation of mass absorption coefficients is based on Chantler’s theoretical data. The core of this method is quantum-mechanical calculation of the cross section of the interaction between an X-ray photon and atomic electrons. This innovation has had a positive influence on the trueness of X-ray microanalysis. Control tests on specimens where the absorption effect is dominant have demonstrated that the results of this analysis are slightly lower (by less than 2%) independently of the matrix absorption interval in which the analytical line is located. As a consequence, the selection of comparison specimens becomes easier: It is sufficient that the specimen under study and the comparison specimen belong to the same isomorphic series and that the intensity of the analytical line of the comparison specimen allows for the measurement with the required accuracy.

In order to determine the seismotectonic activity of faults in the Holocene, we performed trench studies of the ruptures produced by the catastrophic Mogod earthquake (5 January 1967, М = 7.5-7.8, I ₀ = 9-10) in the junction zone of the N-S striking Hulzhin Gol fault and the NW striking Tullet fault. Paleoseismic interpretation of seismic-deformation sections and radiocarbon dating of the samples allowed determining the kinematics and obtaining, for the first time, the absolute ages of paleoevents preceding the Mogod earthquake. Analysis of the tectonic conditions for realization of earthquake sources has shed light on the complex structure of ruptures in the area of the Mogod earthquake epicenter, within which three segments differing in the displacement amplitudes and kinematics have been identified. The research data indicate the repeated activation of the Tulet and Hulzhin Gol faults in the Late Pleistocene-Holocene. The absolute age of the latest activation is 596-994 AD for the Tulet fault and 11,379-6235 BC for the Hulzhin Gol fault. The cumulative deformation from paleoearthquakes in the trench sections in the Tulet fault zone points to at least two displacements of thrust kinematics, with the latest of them having an amplitude of 2.8 m. The paleoearthquake in the Hulzhin Gol fault zone is characterized by the presence of lateral slip. The amplitudes of deformations attest to earlier earthquakes similar in energy to the 1967 Mogod event or even stronger in the fault node. The obtained data on the timing of these earthquakes and the amplitudes of the accompanying displacements made it possible to estimate slip rates along the faults: 0.2-0.3 m/kyr horizontal-slip rates on the Hulzhin Gol fault and 0.5-0.7 m/kyr vertical-slip rates on the Tulet fault.

The Gobi-Altai, Mongolia, includes high mountain ranges that have accommodated the compressional stresses derived from the collision between the Eurasian and Indian Plates. The Gurvan Bogd, which is one of the main mountain ranges in the Gobi-Altai, is a restraining bend along the Bogd sinistral fault. Although surface ruptures did not form near the Artz Bogd during the M_w = 8.1 Gobi-Altai earthquake of 1957, it is still active, as evidenced by a growing topography (i.e., forebergs). Six foreberg ridges have formed in the foreland of the Artz Bogd, which are considered to be the result of surface deformation of alluvial fans due to thrusting. One stream has cut down to expose a foreberg tip, providing the opportunity to explore the slip evolution of the region. Here we map a growing fault structure related to blind thrusting. We identify five faulting events from an analysis of the outcrop and apply optically stimulated luminescence dating to the faulted sedimentary layers, yielding an average slip rate of 0.045 ± 0.007 m/kyr and an earthquake recurrence interval of 5.8 ± 0.5 kyr over the last ~32 kyr. Furthermore, the long-term (~600 kyr) uplift rate of the foreberg is 0.067 ± 0.007 m/kyr, as deduced by dividing the vertical displacement of the alluvial fan surface by the ¹⁰Be surface exposure ages of boulders on the fan. The discrepancy (20-30 %) between these two deformation rates may be due to the different timescales they cover and an along-strike gradient in slip rate.

Terraces at four hypsometric levels were studied in the Vuoksa River basin (northern part of the Karelian Isthmus, NW Russia). New data on nine sections of late Quaternary-Holocene sediments have been obtained. Their age has been determined (for the first time for surface deposits in the studied region) in the interval from 90 to 2 ka. The terrace sediments are disturbed by deformations (faults, folds, and liquefaction) caused by six strong earthquakes in that period. The relationships among the terrace levels, ages, stratigraphy, and structures of loose sediments point to their formation under the impact of differentiated tectonic motions triggered by the activation of the ancient “Vuoksa” fault zone in the late Neopleistocene and Holocene.

In the present paper, the results of a study of the influence of textile materials on the structure of the aerodynamic wake behind blunt-body models in the form of quasi-two-dimensional and cantilever cylinders are reported. The fabrics used were previously examined in the works by co-authors while determining the drag coefficient of a two-dimensional cylinder. The change in diameter in the latter case proved to be not more than 1%, and it was considered insignificant. The use of fabrics has made it possible to reduce the critical Reynolds number to about 2·10⁵. The two- and three-dimensional flows turned out to be similar in terms of fluctuation level, whereas some narrowing of the wake behind the cantilever cylinder occurred due to the three-dimensional structure of the flow. Based on the results of spectral analysis, complete similarity between three- and two-dimensional flows was demonstrated, both for the flow around a smooth cylinder and for the flows around cylinders fitted with textile materials.

Methodological aspects of stagnation-temperature measurement in high-enthalpy supersonic air flows using a thermoelectric transducer (thermocouple) with shielded measuring junction are analyzed. Specific features of thermo- and gas-dynamic processes under the conditions of interest, leading to a substantial deviation of temperatures measured using traditional measuring methods from the true temperatures, are demonstrated. Refinements to the method of determining the temperature of high-enthalpy supersonic air flows allowing one to reduce the deviation from the true temperature are introduced. A mathematical apparatus developed for analysis of experimental data and for quantitative estimation of temperature-measurement error is described. Approbation of the proposed approaches and validation of the developed mathematical models are performed using the results of experimental studies of high-enthalpy supersonic flows. A satisfactory agreement between the results of indirect temperature measurements and specified temperature values is shown. The results of the study can prove useful in the development of techniques and methods, and in the analysis of physical experiments with high-enthalpy flows.

Nano-tracer Planar Laser Scattering (NPLS) technique and pseudo-color processing technology are employed to investigate the flow field after a thickness plate of non-isobaric initial conditions. The results show that the supersonic mixing layer behind the blunt trailing edge will deflect toward the low pressure side which is consistent with the canonical mixing layer. However, there is no laminar region for any unmatched cases and the turbulent state of the mixing layer seems to be restricted for the case of the low-speed side with a higher pressure.

A physical-mathematical model of a plane supersonic boundary layer of a vibrationally excited dissociating gas in the Prandtl approximation is presented. The simplest case of a diatomic gas parameterized according to the data for nitrogen is considered. A number of simplified formulas for calculating the transport coefficients and the dissociation and recombination rates for a molecular-atomic mixture, which are admissible for typical conditions of supersonic and hypersonic boundary layers, are substantiated. Comparative calculations of numerical and locally self-similar solutions of the boundary layer equations on a flat plate for typical conditions of a high-enthalpy wind tunnel and hypersonic flight in the upper atmosphere are performed. It is shown that the atomic concentration profiles calculated on the basis of these approaches differ significantly. In this regard, in order to adequately take into account the effect of chemical reactions in the boundary layer stability calculations, it is necessary to use the profiles of hydrodynamic parameters calculated numerically on the basis of full boundary layer equations. Locally self-similar solutions can serve as initial conditions for numerical calculations.

Film cooling efficiency averaged over the length of a one-row ring of holes for the case of a flat surface with air blowing through fan-shaped holes was estimated experimentally and normalized by the respective efficiency for cylindrical holes in a wide range of injection parameters m (from 0.25 to 5.5) and blowing angles a (from 30° to 75°). Ranges of regime and geometric parameters of film cooling systems in which fan-shaped holes provide a higher cooling efficiency in comparison with cylindrical holes have been identified. With the case of α = 30° taken as an example, we show that very high injection parameters ( m = 4.5¸5.5) in the entrance region of the mixing zone ( x / d < 10) make the relative efficiency decrease from 1.7 to 1.05 with the increase of x / d . Simultaneously, the relative efficiency increases from 1.05 to 1.6 in the main mixing zone ( x / d > 10). Fan-shaped holes provide a higher film cooling efficiency at optimal and high values of m and α = 45° (under all other conditions being identical) in comparison with cylindrical holes both in the entrance region and in the main mixing zone. At α = 75°, the efficiency is higher than throughout the whole examined range of injection parameters and throughout the whole examined range of the normalized distance from the location of the injection place. The relative efficiency decreases from 4 to 1.5 in streamwise direction in the entrance region of the mixing zone ( x/d < 5), and it ranges between 1.5 and 2.5 in the main mixing zone ( x/d > 5) at all values of injection parameter considered in the paper.

Oscillations of a cantilevered rod - fuel element simulator - were experimentally studied in an annular channel with a longitudinal ascending fluid flow using an original sensor built on the basis of the electrical impedance method. The data on the trajectories of the rod axis movement and changes in amplitude and frequency of rod vibrations depending on the velocity of the axial fluid flow are given. The data on rod vibration obtained using the electrical impedance method and high-speed video recording are compared.