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This study examines the geochemical and petrographic characteristics of seven bituminite shales from the Kapurdi mine in the Rajasthan, NW India, in order to assess their organic matter inputs and evaluate the oil-prone potentials. These bituminite shale samples exhibit high total organic carbon (TOC) content (up to 45.11 wt.%). The high TOC contents were correlated with low total sulfur content of less than 1 wt.% and suggest that these bituminite shales were deposited in a fresh lacustrine environment. The dominance of such lacustrine environmental setting was confirmed by the presence of the Botryococcus algae. The analyzed bituminite shales are characterized by a bimodal distribution of normal alkanes and relatively low isoprenoid Pr/Ph, Pr/n-C17 and Ph/n-C18 ratios. These characteristics suggest that these bituminite shales contain a blend of organic matter that was derived primarily from algal lacustrine and other aquatic organic matter, with terrigenous land plants and deposited under suboxic to anoxic environmental conditions. Such findings of the organic matter (OM) input and environmental conditions are consistent with mainly Types I and II kerogen and small amounts of Type II/III kerogen, thus yielding both oil and gas prone to higher concentrations of oil generation potential. The dominance of hydrogen-rich kerogen and oil generation potential is in agreement with the findings of high hydrogen index (HI = 240–425 mg HC/g TOC) and H/C atomic ratio of more than 1.20. The abundance of n-alkene and n-alkane doublets in the pyrolysis–gas chromatography (Py–GC) also indicates that these bituminite shales have potential to generate high concentrations of paraffinic waxy oil. Most of the maturity indicators show that the bituminite shales from the Kapurdi mine have not yet entered the main stage of oil generation window, exhibiting a range of immature stages. Therefore, as highlighted in this study, these bituminite shales can be considered as a good candidate for oil shale reoterting processes to release commercial amounts of oil upon using artificial heating techniques such as hydrothermal conversion.

In this work, the process of low salinity water injection (LSWI) into reservoirs at various salt concentrations was simulated in order to study the change in the oil recovery factor during oil production. The simulation results of the recovery factor were compared with the experimental data. The results demonstrated that the simulation data were in good agreement with the experimental results. In addition, the formation damage (rock permeability reduction) in carbonate core samples was evaluated through coreflood experiments during LSWI in the range of salt concentration and temperature of 1500–4000 ppm and 25–100 °C, respectively. In the worst scenario of LSWI, the rock permeability has reached about 83% of the initial value. Our previous correlation was used to predict the formation damage in LSWI. In this case, the R-squared value between predicted and experimental data of rock permeability ratios was more than 0.97. Furthermore, the recovery factor during LSWI was analyzed with and without the use of DTPMP scale inhibitor (diethylenetriamine penta (methylene phosphonic acid)), and various nanoparticles (TiO2, SiO2, Al2O3). The results of the coreflood experiments showed that the use of scale inhibitor provides an increase in the recovery factor by more than 8%. In addition, the highest recovery factor was observed in the presence of SiO2 nanoparticles at 0.05 wt.%. The oil displacement during LSWI in the porous media with SiO2 particles was better than TiO2 and Al2O3. The recovery factor in the presence of SiO2, TiO2, and Al2O3 with DTPMP was 72.2, 62.4, and 59.8%, respectively. Among the studied nanoparticles, the lowest values of the oil viscosity and interfacial tension (IFT) between oil and water were observed when using SiO2. Moreover, the contact angle was increased by increasing the brine concentration. The contact angle with the use of SiO2, TiO2, and Al2O3 at 0.05 wt.% was reduced by 11.2, 10.6, and 9.9%, respectively.

Recently, interest in on-site heat generation has increased due to injection of thermochemical fluids as a complex effect on well productivity. The method of thermochemical treatment with H2O2 while restoring and increasing the filtration characteristics of the bottomhole formation zone is a relatively new and insufficiently studied technology. The article discusses the key factors affecting the exothermic decomposition of this fluid when this fluid is injected into the well. The heat effects, pressure growth and decomposition time of H2O2 were determined depending on the salinity of the water, the composition of terrigenous rock, and various concentrations of H2O2. Physical 1-D modeling of H2O2 injection was carried out on rock models with mobile and stationary oil, which demonstrated a sharp increase in temperature by 100–240 °C caused by the decomposition of H2O2 due to the catalyst and the presence of catalytic active sites in the rock. As a result of this thermochemical treatment, the rock was partially cleaned of immobile oil and heavy sediments. Injection of H2O2 with a catalyst has shown the effectiveness of displacement of mobile oil from the filled sand model. Thus, the results of this study can provide a preliminary assessment of the effectiveness of H2O2 thermochemical treatment in fields operated at a later stage of development.

A kinetic study of the effect of thermoheliox (inhalation of a helium and oxygen mixture, 70 °C) on the functional hemodynamics of the human brain by functional magnetic resonance imaging was carried out. The dynamic responses of the BOLD signal were found to be biphasic. An empirical equation describing the first phase of the hemodynamic response to visual stimulus was proposed. It was shown that preliminary inhalation of thermoheliox stimulates the hemodynamic responses by slowing down the vasoconstriction.

Molecular modeling tools were applied to design a potential covalent inhibitor of the main protease (Mpro) of the SARS-CoV-2 virus and to investigate its interaction with the enzyme. The compound includes a benzoisothiazolone (BZT) moiety of antimalarial drugs and a 5-fluoro-6-nitropyrimidine-2,4(1.H,3H)-dione (FNP) moiety mimicking motifs of inhibitors of other cysteine proteases. The BZT moiety provides a fair binding of the ligand on the protein surface, whereas the warhead FNP is responsible for efficient nucleophilic aromatic substitution reaction with the catalytic cysteine residue in the Mpro active site, leading to a stable covalent adduct. According to supercomputer calculations of the reaction energy profile using the quantum mechanics/molecular mechanics method, the energy of the covalent adduct is 21 kcal mol−1 below the energy of the reactants, while the highest barrier along the reaction pathway is 9 kcal mol−1. These estimates indicate that the reaction can proceed efficiently and can block the Mpro enzyme. The computed structures along the reaction path illustrate the nucleophilic aromatic substitution (SNAr) mechanism in enzymes. The results of this study are important for the choice of potential drugs blocking the development of coronavirus infection.

The paper systematically considers methods of changing the execution of known standard cryptographic primitives, symmetric and asymmetric, as well as cryptographic protocols using short (low-entropy) keys and small parameters that allow increasing their strength. The proposed changes are related to the introduction of asymmetry in the complexity of the work of legitimate users, which should lead to an increase in the complexity of decryption algorithms for an adversary or cryptanalyst. Security is considered in relation to the use of standard and universal attack methods by the adversary, such as the method of full testing of keys due to the small size of these keys, as well as methods for solving problems of discrete logarithm or factorization of large integers, the size of which is limited by the small size of the cryptosystem parameters. Security is considered in relation to the use of standard and universal attack methods by the adversary, such as the method of full testing of keys due to the small size of these keys, as well as methods for solving problems of discrete logarithm or factorization of large integers, the size of which is limited by the small size of the cryptosystem parameters. This work is of an overview nature, which allows you to look at what is common in the proposed methods for different situations of using cryptography with short keys and small parameters.

Four oil samples were collected from oilfields in the western Siberian Basin, and analyzed using conventional geochemical and physical methods. The results of this study were used to evaluate the oil samples, focusing on the characteristics of their source rocks, including the origin of organic matter input; redox depositional conditions and degree of thermal maturity of their probable source rock were studied. The obtained SARA results show that the examined oils are paraffinic oils owing to their high saturated hydrocarbon fraction values of greater than 70% volume. The observed API gravity values (23.55° to 32.57°) and low sulfur content of less than 0.25% wt indicate that the examined oils are sweet oils and were generated from source rock containing Type-II, with low sulfur content. The low sulfur content combined with the vanadium (V) and nickel (Ni) ratios indicates that the examined oils were scoured from a mixture of aquatic and terrestrial organic matter, depositing under generally suboxic environmental conditions. The n-alkane and isoprenoid distributions, with their ratios and parameters further suggest that the examined oil samples were generated from source rock containing a mixed organic matter input and deposited under suboxic to relatively oxic environmental conditions. Bulk compositions and distributions of n-alkane and isoprenoid indicate that the oil samples were generated from mature source rock.

In this study, bimetallic catalysts based on transition metals CuFe2O4, CoFe2O4 and NiFe2O4 are proposed for catalyzing aquathermolysis reaction during steam-based EOR method to improve in-situ heavy oil upgrading. All upgrading experiments were carried out under a nitrogen atmosphere for 24 h in a 300-ml batch Parr reactor at 250 and 300 °C under high pressure 35 and 75 bar, respectively. To evaluate the catalytic performance of the bimetallic catalysts used, comprehensive studies of changes in the physical and chemical properties of the improved oils, including the viscosity, elemental composition and SARA fractions of oils before and after upgrading processes were used. Furthermore, individual SARA fractions were characterized in detail by Gas Chromatography (GC), High-Performance Liquid Chromatography (HPLC) and Carbon-13 Nuclear Magnetic Resonance (13C NMR), respectively. The results showed that bimetallic catalysts have high catalytic performance at 300 °C for the upgrading of heavy crude oil in viscosity reduction, increasing the amount of saturates (especially alkanes with low carbon number) as a result of thermal decompositions of high molecular weight compounds like resin and asphaltenes leading to their increasing. Furthermore, the upgrading performance is reflected in the improvement of the H/C ratio, the removal of sulfur and nitrogen through desulfurization and denitrogenation procedures, and the reduction in polyaromatic content, etc. CoFe2O4 gives the best performance. Generally, it can be concluded that, used bimetallic based catalysts can be considered as promising and potential additives improving in-situ upgrading and thermal conversion the heavy oils.

The process of organoyttriumoxanealumoxanes co-condensation with chromium acetylacetonate has been studied, as a result chromium-containing organoyttriumoxanealumoxanes were obtained, which are ceramic-forming oligomers and may have fiber-forming properties. Their physicochemical characteristics have been determined by NMR, IR spectroscopy, SEM, TGA, XRD and elemental analysis. It has been found that when the molar ratio of chromium-containing organoyttriumoxanealumoxanes is Al/Y ≈ 2 and Al/Cr ≈ 180 they have fiber-forming properties. Polymer fibers were produced from chromium-containing organoyttriumoxanealumoxanes by melt spinning. The process of thermochemical transformation of synthesized chromium-containing organoyttriumoxanealumoxanes into the ceramic phase has been studied. It is found out that the pyrolysis of chromium-containing organoyttriumoxanealumoxanes leads to the formation of Y3(CrxAl1−x)5O12, YAlyCr1-yO3 and α-(Al2−xCrxO3). That is, these oligomers can be used to create a new generation of heatresistant, optically-transparent, corrosion—and radiation-resistant multicomponent ceramics based on aluminum, yttrium and chromium oxides.

A large amount of crude oils located in front of the combustion front experience low-temperature oxidation (LTO) reactions under relatively constant temperatures over a long period, as a result of the quite slow advancing speed of combustion front during an in situ combustion process. However, the isothermal LTO characteristics of crude oils are still less well understood. In this work, the evolution of mass losses and evolved gases of one crude oil and its saturates–aromatics–resins–asphaltenes (SARA) components during LTO under isothermal conditions was investigated using thermogravimetry connected with Fourier transform infrared spectroscopy. The results suggested that the mass loss at the LTO region was mostly caused by the evaporation of hydrocarbons. Almost no CO2 was emitted from 50 to 350 °C for saturates, aromatics, and resins, whereas the absorbance of CO2 was observed at 300 °C for asphaltenes. During LTO of the oil and its SARA components between 150 and 350 °C, the signal of compounds with C=O group was notably higher than that of compounds with C–O group. Additionally, the effect of the interactions between SARA components on the evolved gases and LTO reaction rate was analyzed. The interactions between SARA components promoted the formation of products with carbonyl group at 100 and 300 °C but inhibited the formation of these products at 200 °C. A better understanding to the gas products emitted by heavy oil LTO could be achieved based on this investigation on the SARA components.

A device for installing the femoral component of hip joint endoprostheses was developed. This provides highly accurate positioning of the stem of the endoprosthesis in primary and revision endoprosthetization surgery. This device provides for intraoperative assessment of offset, limb length, torsion, and alignment of the femoral component of the endoprosthesis with the femur, as well as the comparison of the results with preoperative planning data.

To measure N-acetyl aspartyl glutamate (NAAG) and N-acetyl aspartate (NAA) concentrations in visual cortex activated by a continuous stimulation in a 3 T field. NAAG and NAA spectra were obtained with MEGA-PRESS pulse sequence (TE/TR = 140/2000 ms; δONNAAG/δOFFNAAG = 4.61/4.15 ppm; δONNAA/δOFFNAA = 4.84/4.38 ppm) in 14 healthy volunteers at rest and upon stimulation by a radial checkerboard flickering at a frequency of 8 Hz. Spectra of all subjects were frequency and phase aligned and then averaged. Additionally, to obtain the time-dependency data, spectra were divided into time sections of 64 s each. The intensities of NAA, NAAG and lactate + macromolecular (Lac + MM) signals were defined by integration of the real part of spectra. The heights of the central resonance of NAAG and NAA signals were measured. The NAAG and NAA concentrations, measured with 2.5% and 0.5% error, respectively, were unaffected by visual activation. A significant increase in the Lac + MM signal by ~ 12% is clearly observed. No stimulation-induced time dependency was found for NAAG or NAA, while the increase in Lac + MM was gradual. The concentration values in visual cortex are in good agreement with the 7 T MRS measurements: [NAAG] = 1.55 mM, [NAA] = 11.95 mM. The MEGA-PRESS pulse sequence together with the spectral preprocessing techniques allowed to demonstrate that the concentrations of NAAG and NAA in the visual cortex remain constant during continuous visual stimulation within the margin of error. An increase in the lactate signal intensity signifies the activation of the anaerobic glycolysis in activated visual cortex.

The paper presents the results of studies of the contact physicochemical interaction of a high-temperature nickel alloy with an investment casting shell material of Al2O3–Al2O3 composition. A comparative assessment of the quality of the surface layer of cast products obtained in conventional ceramic shells of the Al2O3–SiO2 composition has been performed. It is found that, unlike the Al2O3–SiO2 investment casting shell mold, the Al2O3–Al2O3 casting mold interacts with the melt to a much lesser extent. The introduction of non-metallic inclusions occurs to a depth of 10–20 μm (Al2O3–Al2O3 ceramic shell mold), which is noticeably lower than that of cast products obtained in the Al2O3–SiO2 ceramic shell mold (up to 40–70 μm). The roughness value of the casting produced in the Al2O3–Al2O3 ceramic shell mold is 2.5–5.0 μm, and in conventional Al2O3–SiO2 shells this value is 3.5–6.5 μm. The process of interaction of a ceramic shell mold material of the Al2O3–Al2O3 composition with a nickel-based superalloy was investigated.

A kinetic model is proposed to describe the key features of development of an acute viral infection, accumulation of antibodies, and immune response in the human body. The general features of immune system stimulation by thermoheliox are described. The model can be used for developing the basis for the application of thermoheliox in the treatment of patients affected by coronavirus.

A kinetic model describing the dynamics of synaptic “discharge”, taking into account the kinetics of the neurotransmitter injection into the synaptic cleft, pH dependence of the enzyme catalytic activity, and proton removal by diffusion was proposed and studied. In the framework of the kinetic model, functioning of the cholinergic synapse was considered. The results of mathematical modeling of the change in the acetylcholine level, induced pH impulse, and the effect of the impulse transmission frequency and acetylcholinesterase inhibition are presented. A physicochemical interpretation was given for a number of key important physiological phenomena, such as neuromuscular paralysis, the mechanism of information recording and storage in the neurological memory, the action of nerve poisons and toxins, and Alzheimer’s disease.

Ceramic-forming organochromiumoxane yttriumoxane alumoxane oligomers with a given molar ratio of Al: Cr and Al: Y, hydrolytically stable in air, have been synthesized. The materials demonstrate fiber-forming properties. It is established that thermal treatment of the obtained oligomers leads to the formation of high purity, heat-resistant multicomponent ceramics based on aluminum, yttrium and chromium oxides, in particular, alumina and garnet fibers modified with chromium oxides.

This article investigates the phase behavior of n-octacosane (C28H58) in the form of an aqueous dispersion with a particle size of about 100 nm. Samples of stable dispersions were prepared by ultrasonication without the addition of surfactants. Studies at various concentrations of n-alkane were performed by differential scanning calorimetry (DSC), powder X-ray diffraction, and light scattering methods. At low n-alkane concentrations, the sensitivity of DSC is not sufficient to detect the paraffin phase transitions. The light scattering method allows determining the phase transition temperatures (melting, crystallization, rotator phases) of n-alkane even in the 10−4 mass% dispersion.

A kinetic model of the development of acute viral infection is proposed and the dynamic behavior of key variables, including the concentrations of viral particles, infected cells, and pathogenic microorganisms, is described. The change in the hydrogen ion concentration in the lungs and pH dependence of the activity of carbonic anhydrase, a key respiration enzyme, are critical factors. An acute bifurcation transition determining either the life or collapse of the system is demonstrated. The transition is associated with exponential increase in the concentrations of participants in the process and with functioning of the key enzyme, carbonic anhydrase. A physicochemical interpretation is given for the therapeutic effect of temperature rise and potential therapeutic effect of "thermoheliox", that is, breathing by heated helium-oxygen mixture.

The proteome of exhaled breath condensate was analyzed by mass spectrometry before and immediately after the thermoheliox procedure and after a 3 h relaxation. The major part of the proteome remained unchanged and there was no extensive cell destruction.

In this research, combustion behaviour of three crude oils with different °API gravities was analysed. The thermogravimetric analyser (TGA) and differential scanning calorimeter (DSC) experiments were performed using three different heating rates (2, 5, and 10 °C min−1) under air atmosphere. The reaction regions, burn-out temperatures, and peak temperatures were determined accordingly. Two main reaction regions, particularly the low-temperature oxidation (LTO) and high-temperature oxidation (HTO) reactions, were figured out in TGA and DSC curves, which suggested exothermic behaviour. Kinetic parameters of the crude oils were determined using model free methods (Ozawa–Flynn–Wall, OFW, and Kissinger–Akahira–Sunose, KAS), which allows the calculation of kinetic properties at progressive conversion degrees without the requirement of any reaction models and f(α) estimations. The variation in activation energy with respect to the conversion degree pointed out that the LTO reaction stage can be subdivided into three subzones. The results indicated that the activation energies were changing depending on the conversion degree, which is an indication of complex reaction mechanisms. The change in activation energy with respect to conversion degree showed slight variation for heavy crude oil compared with that in light crude oil.

The kinase RIP1 acts in multiple signaling pathways to regulate inflammatory responses and it can trigger both apoptosis and necroptosis. Its kinase activity has been implicated in a range of inflammatory, neurodegenerative, and oncogenic diseases. Here, we explore the effect of inhibiting RIP1 genetically, using knock-in mice that express catalytically inactive RIP1 D138N, or pharmacologically, using the murine-potent inhibitor GNE684. Inhibition of RIP1 reduced collagen antibody-induced arthritis, and prevented skin inflammation caused by mutation of Sharpin, or colitis caused by deletion of Nemo from intestinal epithelial cells. Conversely, inhibition of RIP1 had no effect on tumor growth or survival in pancreatic tumor models driven by mutant Kras, nor did it reduce lung metastases in a B16 melanoma model. Collectively, our data emphasize a role for the kinase activity of RIP1 in certain inflammatory disease models, but question its relevance to tumor progression and metastases.

A kinetic inhibitor of methane hydrate formation was developed on the basis of amphiphilic polyurethane. The efficiency of the new reagent was evaluated in a high-pressure reactor with agitation by measuring the time for the beginning of hydrate formation and the change of pressure in the system. The results show the excellent inhibiting effect of amphiphilic polyurethane in increasing the induction time (by 15 times) and reducing the growth rate of hydrates (by 2.5 times) compared with a system with pure water In addition, the urethane-based inhibitor did not show significant growth of methane hydrates after nucleation.

Staphylococcus aureus hibernation promoting factor (SaHPF) is a 22,2 kDa protein which plays a crucial role in 100S Staphylococcus aureus ribosome formation during stress. SaHPF consists of N-terminal domain (NTD) that prevents proteins synthesis by binding to the 30S subunit at the P- and A-sites, connected through a flexible linker with a C-terminal domain (CTD) that keeps ribosomes in 100S form via homodimerization. Recently obtained 100S ribosome structure of S. aureus by cryo-EM shown that SaHPF-NTD bound to the ribosome active sites, however due to the absence of SaHPF-NTD structure it was modeled by homology with the E. coli hibernation factors HPF and YfiA. In present paper we have determined the solution structure of SaHPF-NTD by high-resolution NMR spectroscopy which allows us to increase structural knowledge about HPF structure from S. aureus.