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New insights in the aeromagnetic data over the Central Iranian Microcontinent (CIM) have revealed interesting results for future studies and exploration. This work presents the interpretation of different magnetic analyses and the calculated 3D inversion model to provide important insights into the distribution of igneous rocks in the area that may be traced under significant cover. By analyzing several hundred magnetic susceptibility data points and aeromagnetic anomalies of known igneous rocks over the area, it was determined that mafic-ultramafic intrusive rocks generally have a high magnetic susceptibility and produce a strong magnetic response. Intermediate-felsic intrusive rocks have a low magnetic susceptibility and show a smooth gradient variation and commonly regular shape. Volcanic rocks show a wide range of magnetic susceptibility; therefore, the aeromagnetic anomalies are often random or show strong amplitude with high frequency signals and are rapidly eliminated when an upward continuation is applied. Based on the results of analysis of different magnetic maps and 3D inversion of data, and combining this information with known outcropped of igneous rocks, we revealed 1215 concealed intrusive rocks and 528 volcanic rocks in the area. We also renewed the boundaries of tens outcropped igneous rocks. The known and new mapped igneous rocks can be identified as 12 regions (or zones) for intrusive rocks and 4 regions for volcanic rocks. The results indicate that the mafic-ultramafic rocks are mainly located in the Sistan suture zone of eastern Iran along the Nehbandan fault zone. They also show that the many parts of the Lut block as the main structure of CIM have been under magmatic events, so that most of concealed igneous rocks are distributed in the middle and southern part of the Lut block. Volcanic rocks are widespread in the southeastern and northern parts of the area such as the Urumieh-Dokhtar Magmatic Arc, North Lut, and Bam region.

The latest results on electromagnetic geothermometry and its use in geothermics and geothermal exploration have been covered. Temperature models for the well-known geothermal areas, Larderello-Travale (Italy), Soultz-sous-Forêts (France) and Hengill (Iceland), constructed from electromagnetic sounding data and temperature well logs have been analyzed. 2D temperature model built along the magnetotelluric profile crossing the Travale (Italy) geothermal system allowed to locate a potential supercritical reservoir at the depth between two isotherms, T_SCF ~ 400 °C and T_BDT ~ 600 °C, coinciding with the seismic reflectors, detected earlier. 3D temperature model of the Hengill (Iceland) geothermal area built up to the depth 20 km, using electromagnetic sounding data, allowed us to locate high-temperature magma pockets at shallow depth (2-5 km); these magma pockets can be regarded as targets for geothermal exploration. Joint analysis of the specific resistivity and temperature models, taking into account gravity anomalies, allowed us to locate the zones of different thermal regimes within the crust; this, in turn, explained the observed seismicity pattern by thermo-mechanical properties, rather than by crust spreading. Deep temperature model, built for the Soultz-sous-Forêts (France) geothermal area from magnetotelluric data and temperature well logs, used to locate deep heat sources and predict heat transfer mechanism at depth up to 8 km.

This paper presents the results of experimental panoramic measurements of the temperature field by a method based on the registration of laser-induced fluorescence of the hydroxyl radical (OH) upon excitation of two different transitions (two-line PLIF) in a laminar conical flame of a gas-droplet mixture of ethyl alcohol and air. Laminar flow of the uniformly mixed ethyl alcohol/air mixture with fine droplets is produced by an ultrasonic atomizer inside the liquid ethanol tank. The properties of the two-phase flow at the nozzle outlet without combustion was controlled by a time-of-flight optical sensor. The temperature field was estimated based on the excitation of the Q₁(5) and Q₁(14) lines of the (1-0) transition of the A²∑⁺ - X²π electronic system. The spatial unevenness of the energy distribution in the laser knife illuminating the central plane of the flame cone and the change in the pulse energy from frame to frame were compensated by the use of an additional camera recording the laser radiation intensity distribution in the calibration cuvette.

Structurally stressed hydrocarbons (SSHs) have improved energy performance compared to conventional liquid hydrocarbons. The ignition induction period of mixtures of SSH vapors with air has been studied as a function of temperature and excess air ratio. The results are compared with similar results for mixtures of vapor of n -alkanes with air. The ignition induction periods of mixtures of vapors of two SSH with air are determined. Data on the ignition delay of air-fuel mixtures are required to design engine combustors and to develop and evaluate the possibilities of using new fuels.

Results of studying kerosene combustion in constant-section channels for the Mach number at the channel entrance M = 1.7 are reported. The experiments are performed in channels with variations of the duct shape. The existence of flow regimes with wave structures that do not lead to the development of the pseudoshock mode of combustion is demonstrated. Critical conditions that have to be satisfied for initiation and realization of pre-detonation quasi-stationary combustion are determined.

Results of experimental investigations of the flow in a channel with sudden expansion without and with heat supply into a supersonic air flow are presented. Based on processing experimental data on the time evolution of static pressure on the channel walls, the spectral power of oscillations are determined. The analysis reveals an increase in the spectral power of pressure oscillations in the frequency range of 250 ÷ 400 Hz. The greatest increase in the spectral power is observed in the initial period of the process during ignition and at the end of flame stabilization. In the period corresponding to developed combustion, the peak value of the power spectrum of oscillations decreases, while the range of frequencies is extended to 400 ÷ 600 Hz.

Results of numerical simulations of turbulent reacting flows in a channel with sudden expansion with due allowance for injection of hydrogen jets into a supersonic (M = 4) air flow are reported. The simulations are performed in a three-dimensional unsteady formulation with the use of the ANSYS Fluent software under the test conditions of experiments performed in the IT-302M high-enthalpy wind tunnel. The computations predict a self-oscillatory regime with intense oscillations of pressure and integral heat release. The period-averaged pressure distribution is in reasonable agreement with the experimental measurements, and the frequency of pressure oscillations is within the range obtained in the experiments. Based on a detailed analysis of the flow characteristics within the full cycle of oscillations, the feedback mechanism responsible for the emergence of self-supported oscillations is refined.

Experimental data on the velocity of propagation of a combustion wave in a coal-methane-air mixture with respect to the walls of a closed channel for various concentrations of coal dust are presented. A physico-mathematical model of combustion of this mixture on the basis of equations of gas dynamics and mechanics of disperse media in the one-velocity one-temperature approximation is developed. In the proposed model, the velocity of propagation of the combustion wave with respect to the gas suspension and the burning rate of the coal dust particle are parameters of the model and are determined by providing the consistency between the computed and experimental results. A comparison of the calculated flame velocity with respect to the channel walls in a wide range of mass fractions of coal dust reveals reasonable agreement with the experiments. The proposed approach can be used for estimating the influence of coal dust combustion on the intensity of shock waves formed in coal mines in the case of accidental explosions of methane.

The influence of a relatively small additive of unsaturated gaseous hydrocarbon (propylene) on the detonation wave dynamics in a stoichiometric hydrogen-air mixture was studied by numerical simulation. The influence of the propylene concentration on the development of detonation in the mixture caused by direct initiation with an energy input from the outside in a small volume in a short time was studied at different initial temperatures of the mixture. A detailed mechanism of hydrogen combustion and key propylene hydrogenation reaction were used. Propylene is readily hydrogenated with the removal of atomic hydrogen from the reaction chain. This leads to an increase in the self-ignition delay of the mixture behind the leading shock wave, and at a sufficient concentration of the inhibitory additive, to the decomposition of the cellular detonation wave structure and detonation degeneration.

The authors discuss the influence exerted by the structural features of placers and by the distribution of useful components in them on the efficiency of the resource-saving mining. Considering clustering occurrence of gold ore seams, a geometrization error may reach 100% in some areas of operation. The errors of reserve appraisal are defined, and the applicable approaches to mineral exploration, mining and processing control are discussed. In terms of some placers in Yakutia, it is shown that the main causes of errors in gold reserve appraisal include inaccurate determination of the placer morphology and structure, the width first of all, as well as the gold content.