Russian Journal of Physical Chemistry B最新文献

This study reports the efficient synthesis of novel bicyclic benzylidene thiazole-pyrimidin-3(5H)-one derivatives, including (4-(4-fluorophenyl)-6-phenyl-2-thioxo-1,2,3,4-tetrahydropyrimidin-5-yl)(phenyl)methanone (4), (Z)-6-benzoyl-2-benzylidene-5-(4-fluorophenyl)-7-phenyl-5H-thiazolo[3,2-a]pyrimidin-3(2H)-one (7a), (Z)-6-benzoyl-2-(4-fluorobenzylidene)-5-(4-fluorophenyl)-7-phenyl-5H-thiazolo[3,2-a]pyrimidin-3(2H)-one (7b), (Z)-6-benzoyl-5-(4-fluorophenyl)-2-(4-(methylthio)benzylidene)-7-phenyl-5H-thiazolo[3,2-a]pyrimidin-3(2H)-one (7c), (Z)-6-benzoyl-2-(3,4-dimethoxybenzylidene)-5-(4-fluorophenyl)-7-phenyl-5H-thiazolo[3,2-a]pyrimidin-3(2H)-one (7d), and (Z)-6-benzoyl-2-(3,4-bis(trifluoromethyl)benzylidene)-5-(4-fluorophenyl)-7-phenyl-5H-thiazolo[3,2-a]pyrimidin-3(2H)-one (7e), were comprehensively characterized using IR spectroscopy, ¹H and ¹³C NMR, melting point analysis, and thin-layer chromatography (TLC). To evaluate their pharmacological potential, in silico drug-likeness assessments were performed using SwissADME, BOILED-Egg, and ProTox-II, revealing favorable solubility, gastrointestinal absorption, blood-brain barrier permeability, and toxicity profiles. Notably, molecular docking analyses against critical oncogenic and neurotherapeutic targets—D(2) Dopamine receptor (PDB: 6CM4), Nerve Growth Factor (NGF; PDB: 6NPT), and Melanocortin receptor 4 (MC4R; PDB: 6W25)—demonstrated strong ligand-protein interactions, suggesting their potential therapeutic relevance. Furthermore, molecular dynamics (MD) simulations, including root-mean-square deviation (RMSD) and root-mean-square fluctuation (RMSF) analyses, provided insights into the conformational stability of ligand-receptor complexes, reinforcing their potential as drug candidates. Computational toxicity evaluations classified the compounds under Toxicity Class 4, with LD50 values around 2000 mg/kg, while BOILED-Egg predictions highlighted their differential permeability and absorption properties. Notably, molecules 7a, 7b, 7c, and 7e exhibited blood-brain barrier (BBB) toxicity, and 7e demonstrated immunotoxicity. Binding affinity predictions underscored molecule 7c as the strongest D(2) Dopamine binder (–8.603 XP GScore), while molecule 7b exhibited optimal Nerve Growth Factor (NGF) interactions (–6.677 XP GScore) and molecule 7d showed enhanced binding with MC4R (–7.825 XP GScore). Structural insights from torsional profile analyses further emphasized conformational stability and ligand flexibility, crucial parameters for optimizing lead compounds in drug development.

Flame acceleration in an acetylene-oxygen-nitrogen mixture in a channel due to the formation of a vortex flow on the boundary layer scale is studied numerically. The simulation is carried out using the complete system of gas dynamics equations for a reacting medium, taking into account the reduced mechanism of combustion kinetics in a setup simulating the gas flow in a channel by specifying the motion of the side walls. It is shown that when the flow regime changes from stable to unstable, an exponential increase in the flame propagation velocity occurs. The results obtained in this paper qualitatively describe the relationship between the instability of the boundary layer and the flame evolution scenario in the channel.

Germanium/tin-containing silicon oxide [SiO–(GeO/SnO)] nanoclusters have been designed with different Si/Ge/Sn content and charchterized as electrodes for magnesium-ion batteries (MIBs) due to forming MgBe[SiO–GeO], MgBe[SiO–SnO], MgCa[SiO–GeO] and MgCa[SiO–SnO] complexes. In this work, alkaline earth metals of magnesium (Mg), berelium (Be) and calcium (Ca) have studied in hybrid Mg-, Be-, Ca-ion batteries. A vast study on H-capture by MgBe[SiO–(GeO/SnO)] or MgCa[SiO–(GeO/SnO)] complexes was probed using computational approaches due to density state analysis of charge density differences (CDD), total density of state (TDOS), electron localization function (ELF) for hydrogenated hybrid clusters of MgBe[SiO–GeO], MgBe[SiO–SnO], MgCa[SiO–GeO] and MgCa[SiO–SnO]. Higher Ge/Sn to Si content can increase battery capacity through MgBe[SiO–GeO], MgBe[SiO–SnO], MgCa[SiO–GeO] and MgCa[SiO–SnO] nanoclusters for Hydrogen adsorption process and might improve the rate performances by enhancing electrical conductivity. Besides, [SiO–(GeO/SnO)] anode material may advance cycling stability by preventing electrode collapse and enhances the capacity due to higher surface capacitive effects.

We have studied the influence of pressure and the concentration of a substance being micronized in solution on the size and morphology of salbutamol sulfate particles produced via supercritical antisolvent (SAS) precipitation. The results demonstrate that SAS micronization from ingle-phase and two-phase methanol–CO₂–salbutamol sulfate systems leads to the formation of amorphous spherical particles and crystalline particles elongated in one direction, respectively. If the process is run in the single-phase system, we observe precipitation of considerably smaller particles in comparison with the two-phase region. Moreover, the size of the particles prepared by the SAS method via micronization from the two-phase and single-phase systems decreases and increases with increasing salbutamol concentration in solution, respectively. The main cause of this distinction is related to the mechanisms of mixing of the antisolvent and solution. In the case of the two-phase system, crystallization occurs in droplets at a considerably larger fraction of the solvent in comparison with the single-phase system and, accordingly, at a lower degree of local supersaturation.

As electromagnetic wave absorption material, a kind of porous carbon microsphere was obtained through the high-temperature carbonization of the pre-prepared flower-like urea-formaldehyde resin microspheres. The study investigated urea-formaldehyde resin-based carbon microspheres prepared under different formaldehyde-to-urea molar ratios and carbonization temperatures. The morphology and structure of the carbon microspheres were analyzed by SEM and Raman spectroscopy. The results show that the carbon microspheres have abundant folds and pores, good dispersion and high specific surface area. Through the evaluation of electromagnetic wave absorption performance, it was determined that urea-formaldehyde resin-based carbon microspheres synthesized under the conditions of the formaldehyde-to-urea molar ratio of 1.0 and carbonization temperature of 800°C exhibited optimal performance. At a thickness of 2 mm, the maximum reflection loss at 16.38 GHz reached –40.66 dB, with the maximum effective absorption bandwidth exceeding 6.02 GHz. The excellent electromagnetic wave absorption performance of the materials can primarily be attributed to the complex reflection and scattering processes induced by its porous structure and irregular morphology, as well as the effective attenuation of microwaves facilitated by the porous carbon structure.

Mathematical models of solubility of various groups of organic substances in supercritical carbon dioxide are proposed. The developed models are based on the method of quantitative structure–property relationship (QSPR). The key feature of the method is the construction of a dependence between the predicted property and parameters that numerically reflect the features of the molecular structure (molecular descriptors). In the study, molecular descriptors affecting solubility are selected and dependencies of the solubility of organic substances in supercritical carbon dioxide (SC–CO₂) are constructed using the multiple linear regression method. The models are developed using the developed software and analytical package and an original database containing information on the solubility of substances in SC–CO₂ and information on the molecular descriptors of dissolved substances. The predictive ability of the developed models is evaluated. Based on the obtained results, a conclusion about the prospects of using the developed models for predicting the solubility of substances in supercritical carbon dioxide is made.

The dependencies of the reaction mixture density on temperature are analyzed for the following processes: (1) catalytic CO₂ hydrogenation and (2) conversion of phenol and cyclohexanol in sub- and supercritical water. Density measurements were performed using a Lazerokhim fiber-optic densitometer. The state of the waveguide end face surface after measurements at elevated temperature was analyzed by scanning electron microscopy (SEM). It was found that for nonaqueous reaction mixtures, the laser-optical density monitoring method is applicable in a wide range of temperatures and pressures. In the case of water and water–organic mixtures, correct determination of densities is possible only at temperatures of 25–190°C, since an increase in the temperature above 200°C leads to irreversible etching of the silicate optical waveguide end face surface by the aqueous fluid.

We report an experimental study of oxidation of aluminum with sub- and supercritical water in the range 350–410°C for 60 to 300 min. The results demonstrate that oxidation under such conditions yields aluminum hydroxides and oxides with a large surface area. The specific surface area of the oxidation products has been shown to vary nonmonotonically with process temperature, which is caused the formation of various compounds and aluminum oxide phases. Calcination of the oxidation products at 550°C led to the formation of γ-, χ- and α-Al₂O₃, in relative amounts determined by the temperature and duration of oxidation in water.

A magnetic-activated carbon nanocomposite was synthesized through the ZnCl₂–FeCl₃ activation of tea waste residue by optimizing the synthesis conditions. The typical nanocomposite was created at 600°C for 1 h, employing a 1 : 1 activator: feed soaking ratio. The BET surface area, FESEM, VSM, pore volume, XRD, and EDX of the nanocomposite were identified. The nanocomposite had a specific surface area of 928.77 m²/g and a 2.80 nm mean pore diameter, demonstrating its mesoporosity. Dibenzothiophene adsorption from model oil (200 ppm dibenzothiophene /hexane) and Cr(VI) from an aqueous solution (200 mg/L) were tried by this adsorbent. The maximum elimination efficiency of dibenzothiophene from the solution was 99.02%, utilizing 0.35 g of the nanocomposite at 25°C for 30 min. Simultaneously, the highest elimination efficiency of Cr(VI) from aqueous solution amounted to 97.50%, implementing 0.20 g of the nanocomposite at 25°C for 120 min. Also, the nanocomposite ascertained its ability to remove S-compounds from real gasoline fuel and Cr(VI) from its solution in actual water. Adsorption of pollutants from their liquid phases by the nanocomposite fitted best with the Langmuir adsorption isotherm and the pseudo-2nd-order model. The reusability studies of the spent adsorbent showed its activity even after 5 reuse cycles with an efficiency exceeding 91.0%. In conclusion, the nanocomposite originated from waste tea residue can be recommended as a potential adsorbent to strip various pollutants from different liquid phases.

In this work, the structural characteristics, electronic, elastic, optical properties of chiral semiconductor Ag₃AuTe₂ under pressure were calculated using the first-principle calculation method. The computed structural parameters have good agreement with experimental data. For the first time, the obtained elastic constants reveal the chiral semiconductor Ag₃AuTe₂ is mechanically stable between 0 and 12 GPa. The mechanical parameters such as the bulk modulus, shear modulus, Young’s modulus, and elastic anisotropy as a function of pressure are calculated from the obtained elastic constants. All these polycrystalline elastic moduli exhibit a monotonic feature as a function of pressure. The Poisson’s ratio, and Pugh’s criterion indicate that the chiral semiconductor Ag₃AuTe₂ is ductile against pressure. In optical properties, frequency dependent parameters such as real and imaginary parts of dielectric function, refractive index, reflectivity, absorption coefficient and extinction coefficient are calculated and analyzed under pressure.