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The Severo-Ketskaya parametric well was drilled by AO NPC Nedra to a depth of 5200 m in the period 2021-2023. The well is located in the southwestern part of the Pre-Yenisei sedimentary basin in the dome zone of the large anticlinal structure of the same name, buried under the Meso-Cenozoic cover. The well uncovered a new carbonate-terrigenous section of the Vendian and carbonate deposits, presumably of Riphean age, for the Pre-Yenisei sedimentary basin. The article substantiates the stratigraphic boundaries of the Vendian on the basis of geophysical correlations with typical sections of the south-west Siberian Platform, presents the general lithological characteristics of the Vendian section and the exposed part of the Riphean (?). According to the data of the preliminary core study, the results of geophysical studies and tests of objects, the deposits of the Upper and Middle Danilovsky subhorizons are the most promising for oil and gas accumulation in the Vendian rock formations in the borehole drilling area. The results of geochemical studies of sections of parametric wells do not allow us to associate high oil and gas potential with the Proterozoic deposits of the Pre-Yenisei sedimentary basin.

We present the fundamental principles of our technology - GeoArrhenius/SpectrOptim for the justification and reconstruction of compositional kinetic spectra. The advantage of this technology is the reliable separation of gaseous hydrocarbons on the chromatogram and the reconstruction of multicomponent (with an arbitrary number of components) kinetic spectra at the early catagenesis based on neural network modeling. Applying this technology in hydrocarbon system modeling provides the opportunity to accurately assess the volumes of hydrocarbons generated by a source rock and consequently enables the evaluation of hydrocarbon resources in an exploration area. This approach reduces the reliance on external and internal analogies during calculations, as well as the expert opinions of geological researchers.

A reaction mechanism for the ignition and combustion of three-component C₃H₈/nC₄H₁₀/iC₄H₁₀ surrogates of alternative fuels based on liquefied petroleum gases has been developed. The mechanism describes the ignition of the surrogates at both high and low temperatures, as well as in the region of inverse temperature dependence of ignition delay time. The mechanism includes 442 reactions for 84 components. The results of testing the mechanism are presented using experimental data: ignition delay time of isobutane mixtures, hydrocarbon gas mixtures containing propane, n-butane, and isobutane (T₀ = 670 ÷ 1478 K, ρ₀ = 1 ÷ 30 atm, φ = 0.3 ÷ 2.0), normal flame propagation velocity in isobutane-air mixtures, and the concentration of the main isobutane oxidation products in a flat-flame burner.

The excitation and propagation of exothermic reaction waves in a closed channel filled with gaseous oxygen at initial pressures of 0.1 to 2 MPa was studied. The waves were excited by a hot nichrome coil coated with a small amount of VM-4 vacuum oil or melted fat. The wave parameters and initial pressures at which flame propagation occurs in the channel were determined.

The most interesting and important gas-dynamic and kinetic parameters of combustion, explosion, and detonation of ammonia/oxygen combustible systems of stoichiometric, lean, and rich compositions with the addition of molecular nitrogen (transition from fuel-oxygen to fuel-air mixtures) are presented. The same data are presented for fuel-air mixtures ranging from the lower to the upper concentration limit and with varying initial pressures. From an explosion safety perspective, the most important data are on the critical initiation energy, which allows for an analysis of the relative hazard of various mixtures. Critical energy E_* is defined as the minimum energy of the initiator that ensures the propagation of combustion and detonation waves in the mixture under study: the lower the E_*, the more hazardous the mixture. Data on the detonation cell size, which is used to determine the characteristic parameters of combustion chambers, which have the dimension of length, are also presented.

Continuous spin and multifront detonation modes of carbon-free ammonia/hydrogen-air fuel-air mixtures were implemented for the first time in a flow-through annular cylindrical combustion chamber with a diameter of 503 mm. Binary fuel (ammonia/hydrogen) with H₂ mass fractions in the fuel of 0.105 ÷ 0.485 was studied in the range of specific mixture flow rates of 22 ÷ 347 kg/(s ∙ m²) at an excess fuel coefficient of φ= 0.47 ÷ 1.55. In ammonia/hydrogen --- air mixtures with fuel of three compositions NH₃ + 8H₂, NH₃ + 4H₂ and NH₃ + 2H₂, single-wave and two-wave modes of continuous spin detonation with a velocity of 1.15 ÷ 1.59 km/s and a wave rotation frequency of 0.73 ÷ 1.81 kHz at φ= 0.73 ÷ 1.2 are realized, and for the NH₃ + H₂ composition --- continuous multifront detonation with two counter transverse detonation waves with a frequency of about 1.0 kHz at φ= 0.72 ÷ 1.0. The region of implementation of continuous spin detonation and continuous multifront detonation modes is determined depending on the ammonia content in the binary fuel and on the pressure in the air manifold. High-frequency sensors measured pressure profiles in the air manifold and in the combustion chamber in the region of rotation of transverse detonation waves. Thrust forces and specific impulses were determined. The highest thrust impulses obtained in the chamber were 2300, 1500, 1350, and 900 s for mixtures with hydrogen mass fractions in the binary fuel of 0.485, 0.32, 0.19, and 0.105.

A study was conducted on the detonation of oxyacetylene mixtures diluted with helium or argon in an extended channel with a flow-through feed of explosive mixture components at atmospheric pressure. The steady-state detonation velocity, temperature, and dynamic pressure of the products were calculated. The limits of self-sustaining detonation in a 26 mm diameter channel were determined. These limits are achieved by diluting an equimolar and stoichiometric mixture to 92% with both helium and argon. Near these limits, near-spin detonation is initiated without a noticeable transition from combustion to detonation by a booster charge of an equimolar oxyacetylene mixture, the volume of which does not exceed 180 cm³ or 13 channel calibers. Detonation coatings made of pure titanium were obtained using both helium and argon as the purging gas. Helium produces a dense coating with a porosity of <0.5% and a microhardness of 370 HV300. Argon can be used to produce coatings with a developed surface and high (tens of percent) porosity in the surface layer, which have potential for use in catalytic reactors and the production of medical implants.

Using the Euler equations in a two-dimensional plane, we numerically study the incidence of a shock wave on a near-wall gas bubble (a transverse cylinder) filled with a hydrogen-oxygen mixture doped with xenon. Gas combustion is modeled using detailed kinetics, taking into account 19 reversible reactions. A high-order finite-difference method of the WENO class is applied. The processes of shock wave refraction and reflection, as well as the focusing of secondary shock waves, are described. Various modes of detonation initiation in the bubble are discovered: direct detonation, refraction and reflection of the wave from the wall, and focusing of shock waves on a plane of symmetry near the wall. Based on a series of calculations, the dependence of ignition modes and threshold Mach numbers of the incident wave on the bubble shape is determined. It has been shown that the combination of wave focusing on the bubble and reflection from the wall leads to a significant reduction in threshold Mach numbers, both compared to a flat layer of combustible gas in front of the wall and compared to a free bubble without a wall.

The results of an experimental study of the ignition of electrode carbon samples heated by an integrated thermal radiation flux are presented. The experiments were conducted using a Uran-1 radiation heating system in an oxygen atmosphere at different pressures (0.1 and 1.1 MPa) with a heat flux density of 75 to 314 W/cm² incident on the sample surface. Ignition temperatures and the dependence of the ignition delay time on the heat flux density were obtained. The measured dependences were used to determine the formal kinetic constants of the process within a heterogeneous ignition model.

Using a coupled combustion model of a metallized composite solid propellant, this study examines transient fuel combustion under harmonic pressure variations above the fuel surface. The combustion model takes into account chemical reactions in the condensed and gas phases. Above the fuel surface, convection and diffusion of gas mixture components, two-phase flow, velocity and thermal nonequilibrium of the phases, and combustion of aluminum particles are considered. Boundary conditions for equal mass and energy fluxes are imposed on the fuel surface. The results of a computational and theoretical study of the dependence of the fuel combustion rate on the amplitude and frequency of pressure oscillations are presented. The study was conducted for two reaction orders in the gas phase. The influence of pressure oscillation frequency on the amplitude of fuel combustion rate variations is determined.