D. O. Kalmykov, T. S. Anokhina, R. Yu. Nikiforov, N. A. Belov, M. G. Shalygin, S. Banerjee, T. N. Rokhmanka, S. D. Bazhenov
{"title":"Physicochemical and Gas-Transport Properties of Membranes Based on Ultem and Siltem Polyetherimides for Hydrogen Recovery in Ammonia Industry Systems","authors":"D. O. Kalmykov, T. S. Anokhina, R. Yu. Nikiforov, N. A. Belov, M. G. Shalygin, S. Banerjee, T. N. Rokhmanka, S. D. Bazhenov","doi":"10.1134/S0036024425702577","DOIUrl":"10.1134/S0036024425702577","url":null,"abstract":"<p>The physicochemical and transport properties of polymer films based on polyetherimides Ultem-1000 and Siltem-1700 are presented. Using the gravimetric method, the sorption, diffusion, and permeability coefficients for a number of model gases (N<sub>2</sub>, CH<sub>4</sub>, O<sub>2</sub>, CO<sub>2</sub>) were determined, and ideal selectivities for key gas pairs (O<sub>2</sub>/N<sub>2</sub>, CO<sub>2</sub>/CH<sub>4</sub>) were calculated. It was found that membranes based on Siltem demonstrate significantly higher permeability for all gases studied, but are inferior to Ultem in selectivity. The transport of water (H<sub>2</sub>O) and ammonia (NH<sub>3</sub>) vapors through continuous polymer films was also investigated. The water vapor permeability coefficient was 2570 Barrer for Siltem and 1720 Barrer for Ultem; for NH<sub>3</sub> these values were 29 and 10 Barrer, respectively. The influence of the composition of the casting solution on the transport characteristics of Ultem membranes was studied: the highest permeability values were achieved using <i>N</i>‑methylpyrrolidone (NMP) as a solvent. The obtained data can be used in the design of membrane systems for the separation of hydrogen-containing gas mixtures, including ammonia recovery and hydrogen purification processes within the framework of low-carbon energy.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"3122 - 3129"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Study of the Effect of Carbon Nanotubes and Graphene on the Passage of Terahertz Radiation through Polysulfone Polymer Films","authors":"E. R. Khazeeva, Yu. S. Eremin, A. M. Grekhov","doi":"10.1134/S0036024425702589","DOIUrl":"10.1134/S0036024425702589","url":null,"abstract":"<p>The influence of carbon nanotubes (CNT) and graphene on the optical density of polysulfone (PSF) polymer films for radiation in the terahertz range was investigated. The influence of film thickness and nanoparticle concentration on the optical properties of composites was studied. It has been established that an increase in the concentration of nanoparticles and film thickness leads to an increase in the absorption capacity of the material. The studies of the absorption parameters of electromagnetic (EM) radiation in the terahertz (THz) range in films up to 100 µm thick showed the effect of the percolation structure of the embedded phase and the correlation of wavelengths and parameters of the composite material structures.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"3130 - 3135"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Synthesis and Physicochemical Characterization of a Choline-Tryptophan Based Ionic Liquid in Aqueous Medium at Different Temperatures","authors":"Vibek Srichandan, Prachi Prava Mohapatra, Itishree Panda, Malabika Talukdar, Sanghamitra Pradhan","doi":"10.1134/S0036024425702358","DOIUrl":"10.1134/S0036024425702358","url":null,"abstract":"<p>In the present work, synthesis, and physicochemical investigations of choline-tryptophan [Ch][Trp] based IL have been reported. The synthesized [Ch][Trp] IL was fully characterized by Fourier transform infrared (FTIR), ultraviolet (UV), fluorescence, nuclear magnetic resonance (<sup>1</sup>H and <sup>13</sup>C NMR) spectroscopy. The thermophysical properties namely density and ultrasonic velocity of the synthesized IL in aqueous medium have been monitored in the temperature range of 293.15–313.15 K at 5 K interval. Derived properties like apparent molar volume (<span>({{V}_{phi }})</span>), partial molar expansibility (<span>(E_{phi }^{0})</span>), isentropic compressibility (<span>({{K}_{{text{S}}}})</span>), isothermal compressibility (<span>({{K}_{T}})</span>), apparent molar isentropic compressibility (<span>({{K}_{{{text{s}},phi }}})</span>) and hydration number (<span>({{n}_{{text{H}}}})</span>) have been calculated.The increase in density values with rise in concentration of IL reveals that there is association between the constituents due to closeness. But as the temperature rises, the ionic mobility intensifies leading to expansion in volume and lowering of density. A decreasing trend of <span>({{V}_{phi }})</span> has been noticed at higher concentration of IL due to large engagement of water molecules in the solvation process leading to strong electrostriction and overlapping of hydration co-spheres. It has also been observed that the water molecules located in the primary hydration shells are incompressible due to electrostriction but the water molecules out of the electrostatic field are main contributors to the isentropic compressibility of the aqueous IL mixture.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"2922 - 2936"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Phase and Isotopic Equilibria between Boron Trichloride and Its Solution in Perfluorodecalin","authors":"S. I. Frolova, P. I. Ivanov, A. V. Khoroshilov","doi":"10.1134/S0036024425702565","DOIUrl":"10.1134/S0036024425702565","url":null,"abstract":"<p>The phase and isotopic equilibria between boron trichloride and its solution in perfluorodecalin have been studied. The results of experiments on saturation of perfluorodecalin with boron trichloride, performed at temperatures from 278 to 303 K, indicate high solubility of BCl<sub>3</sub> in perfluorodecalin, which varies from 16.09 ± 0.02 to 0.099 ± 0.007 mol BCl<sub>3</sub>/mol perfluorodecalin. The heat of dissolution of BCl<sub>3</sub> in perfluorodecalin is estimated at –(4–6) kJ/mol BCl<sub>3</sub>, which corresponds to the range of the van der Waals interaction. The single separation factor of boron isotopes during the dissolution of BCl<sub>3</sub> in perfluorodecalin was determined based on the results of the isotope analysis of the gas and liquid phases: α = 1.0085 ± 0.0036 and 1.0128 ± 0.0066 at 12 and 5°C, respectively.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"3108 - 3113"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. P. Nebesskaya, A. V. Balynin, A. A. Yushkin, A. S. Lyadov, V. V. Volkov
{"title":"Application of Fine Porous Ultrafiltration Pan Membranes for Used Engine Oil Treatment","authors":"A. P. Nebesskaya, A. V. Balynin, A. A. Yushkin, A. S. Lyadov, V. V. Volkov","doi":"10.1134/S0036024425702620","DOIUrl":"10.1134/S0036024425702620","url":null,"abstract":"<p>The application of polyacrylonitrile (PAN) ultrafiltration membranes to the treatment of used engine oil (UEO) was investigated. A two-stage purification scheme was developed, comprising filtration through PAN membranes with pore sizes of 23 nm (M-20) and 4.9 nm (M-5). The results demonstrated that the M-5 membrane exhibits high permeability, 2.0 ± 0.4 L/(m<sup>2</sup> h bar), and strong fouling resistance, with toluene washing restoring up to 93% of its initial permeability. Physicochemical and elemental analyses confirmed a reduction in oxygen, sulfur, metals, and high-molecular-weight compounds. Spectroscopic studies (FTIR and NMR) revealed efficient removal of polycyclic aromatic hydrocarbons and oxidation products. The two-stage filtration system employing PAN membranes provides efficient treatment of UEO, making the proposed method promising for further industrial application.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"3159 - 3166"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nanofiber Aerosol Filters","authors":"V. A. Kirsh, A. A. Kirsh","doi":"10.1134/S0036024425702590","DOIUrl":"10.1134/S0036024425702590","url":null,"abstract":"<p>Features and advantages of highly efficient fine-fiber filters for capturing submicron aerosol particles are discussed. Quality criteria for filters made of nanofibers and fibers coated with radial nanowhiskers with account for the gas slip effect at low and intermediate Knudsen numbers are determined.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"3136 - 3144"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. S. Zhamsueva, A. S. Zayahanov, V. V. Tsydypov, T. S. Bal’zhanov, A. L. Dement’eva, A. V. Starikov
{"title":"Modeling of Atmospheric Aerosol Deposition on Different Types of Underlying Surface (for the Coastal Zone of Lake Baikal As an Example)","authors":"G. S. Zhamsueva, A. S. Zayahanov, V. V. Tsydypov, T. S. Bal’zhanov, A. L. Dement’eva, A. V. Starikov","doi":"10.1134/S003602442570270X","DOIUrl":"10.1134/S003602442570270X","url":null,"abstract":"<p>Atmospheric aerosol deposition on the underlying surface in a forest area and over meadow vegetation on the southeastern coast of Lake Baikal have been studied. Based on the measurements of the height profiles of the number concentration of fine aerosol, it is shown that the aerosol concentration gradients over meadow vegetation are significantly higher than under the tree crown in the forest area and differ significantly. The concentration gradients of fine aerosol (FA) and submicron aerosol (SMA) particles under the tree crown in the forest vary within narrow ranges compared to those in the open country (meadow) and can be negative or positive (<i>dC</i>/<i>dh</i>). In experiments over meadow vegetation, the maximum concentration gradient was 180 (particles/cm<sup>3</sup>)/m for fine particles in the daytime and 4 (particles/cm<sup>3</sup>)/m for submicron aerosol in the morning. In the forest, the maximum is 110 (particles/cm<sup>3</sup>)/m for FA in the daytime and 1 (particle/cm<sup>3</sup>)/m for SMA particles. The low values of gradient under the tree canopy indicate that the tree crown has a significant effect on the deposition of aerosol particles in forest vegetation.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"3215 - 3226"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. S. Sokolov, A. E. Safronov, S. N. Diesperov, A. R. Gareev, A. A. Belogorlov
{"title":"Effect of the Non-Uniform Impregnation of Monofilaments on the Process Parameters of Automated Winding","authors":"G. S. Sokolov, A. E. Safronov, S. N. Diesperov, A. R. Gareev, A. A. Belogorlov","doi":"10.1134/S0036024425702668","DOIUrl":"10.1134/S0036024425702668","url":null,"abstract":"<p>The laser heating of a cell of a representative volume of thermoplastic tape is modeled, and the procedure for generating filaments within the cell is revised. The bi-parametric problem of finding the optimum process for automated layup and winding is solved, and samples are manufactured to determine the specific energy of delamination at the limiting process parameters of a robotic layup system.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"3186 - 3191"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Kh. Mudarisova, A. F. Vakhitova, I. V. Novoselov
{"title":"Synthesis and Spectral Characteristics of Copper Complexes Based on Pectin Modified with L-Arginine, L-Alanine, and L-Aspartic Acid","authors":"R. Kh. Mudarisova, A. F. Vakhitova, I. V. Novoselov","doi":"10.1134/S003602442570253X","DOIUrl":"10.1134/S003602442570253X","url":null,"abstract":"<p>Polymer ligands based on apple pectin modified with amino acids (<i>L</i>-arginine, <i>L-</i>alanine, and <i>L‑</i>aspartic acid) were synthesized and characterized by IR and <sup>13</sup>C NMR spectroscopy, polarimetry, viscometry, and elemental analysis. Based on the synthesized polymer ligands, new metal-polymer complexes of copper(II) were synthesized:. The stoichiometry of the resulting metal complexes and the pH ranges of their existence were determined using the spectrophotometric method and elemental analysis data. It has been established that the modification of pectin with amino acids increases the stability of copper-containing polymer complexes compared to their homoligand analogs in a medium simulating gastric juice.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"3094 - 3103"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. V. Shafigulin, K. Yu. Vinogradov, O. V. Korchagin, V. M. Davydov, E. O. Tokranova, A. V. Bulanova
{"title":"Efficient Catalysts for Oxygen Electroreduction Based on Carbon Nanotubes and Pyrolyzate of the Metalorganic Framework MIL-53(Al)","authors":"R. V. Shafigulin, K. Yu. Vinogradov, O. V. Korchagin, V. M. Davydov, E. O. Tokranova, A. V. Bulanova","doi":"10.1134/S0036024425702462","DOIUrl":"10.1134/S0036024425702462","url":null,"abstract":"<p>The electrocatalytic properties of materials synthesized on multi-walled carbon nanotubes (MWCNTs) and pyrolyzate of the metalorganic framework Pyr_MIL-53(Al) in the oxygen reduction in an alkaline medium were compared. The catalysts were obtained by doping the supports with iron and cobalt phthalocyanines and modifying them with palladium. According to the IUPAC classification, the materials are type IV adsorbents, having a hysteresis of the H3 type, which indicates the presence of slit-like pores. When the MWCNTs are doped, the ordering of the catalyst surface significantly decreases, probably due to the formation of amorphous carbon during the decomposition of phthalocyanines. When Pyr_MIL-53(Al) is doped, the surface ordering increases, which is probably associated with graphitization of the carbon of the initial Pyr_MIL-53(Al) during the joint pyrolysis with phthalocyanines. The phase composition of the obtained catalysts was studied by XRD: the metals are present in the form of alloys and oxides. In the linear voltammetry mode, the MWCNT_CoPc_FePc_Pd catalyst showed activity in the oxygen reduction reaction (ORR) comparable to that of the commercial platinum electrode; the number of electrons participating in the reaction was more than 3.8. The MWCNT_CoPc_FePc_Pd catalyst exhibited a large electrochemically active surface area and high corrosion resistance associated with the self-activation effect. The trials of the MWCNT_CoPc_FePc_Pd catalyst under membrane electrode unit (MEU) conditions showed high efficiency of the material as an oxygen reduction catalyst for alkaline fuel cells.</p>","PeriodicalId":767,"journal":{"name":"Russian Journal of Physical Chemistry A","volume":"99 12","pages":"3037 - 3049"},"PeriodicalIF":0.8,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145698402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}