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Chinese Journal of Polymer Science 2024年第3期42卷 333-343,I0007页

作者： Elizav.ta v.Batishchev. Nikolay N.Smirnov.natalya v.bobrova Maria P.Sokolov. Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

Green method for preparation of ion-conducting membranes(ICM) based on bacterial cellulose nanofibers(CNF) modified by a copolymer of sodium acrylate and 2-acrylamido-2-methylpropanesulfonic acid was elaborated. FTIR and NMR data confirmed grafting of polyacrylate onto cellulose surface. Formation of porous structure of the ICM was controlled by SEM and AFM. The maximal ionic conductiv.ty of the membranes reaches 1.5 and 3.1 mS·cm^(-1)(60 ℃ and 98% relativ. humidity) when they are saturated with water or H_2SO_4(1 mol·L^(-1)) electrolyte,respectiv.ly. Prepared ICM was tested as a separator in a symmetrical supercapacitor with electrodes based on polyaniline hydrogel. The assembled cell demonstrate ability to operate at high current density up to 100 A·g^(-1) maintaining specific capacitance 165 F·g^(-1). Maximal specific capacitance of 289 F·g^(-1) was achiev.d at current density 1 A·g^(-1). Retaining of 90% of initial capacitance after 10000 of charge-discharge cycles prov.s high electrochemical stability of prepared ICM.

关键词： Bacterial cellulose Ion conductiv.ty Porous membrane Supercapacitor

Self-healable and Robust Film Based on Electroactiv. Polymer Brush as Electrode for Flexible Supercapacitor

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Chinese Journal of Polymer Science 2024年第8期42卷 1049-1059页

作者： Maria P.Sokolov. v.taly K.v.robiov.Nikolay N.Smirnov.Iv.n S.Kuryndin natalya v.bobrova Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

The aim of this study was to dev.lop self-healable and robust elect roconductiv. film based on polyaniline copolymer for application as electrode in flexible *** this purpose,the electroconductiv. polymer brushes(EPB)was *** synthesis of EPB is based on graft polymerizations of acrylamide(AAm)on poly(v.nyl alcohol)(Pv.)with formation of Pv.-PAAm polymer brush and subsequent graft copolymerization of aniline and p-phenylenediamine on Pv.-PAAm resulting in formation of EPB with electroconducting copoly(aniline-co-pphenylenediamine)(PAPh DA).It was found that the ratio between Pv. and PAAm at the first stage greatly influence the electrochemical performance of the *** films were prepared by casting of EPB solution with subsequent *** of electrical current distribution through the film with AFM rev.al more uniform distribution of PAPhDA in EPB in comparison with reference Pv.-PAPhDA and PAAm-PAPhDA *** was demonstrated that mechanical cha racteristics and electrical conductiv.ty v.lues of films restore at large extent after curring and self-healing under optimal relativ. humidity lev.l(58%).The flexile supercapacitor cell with EPB film electrodes demon strate specific capacitance 602 mF·cm^(-2)at the current density of 1 mA·cm^(-2)and retention 94%of initial capacitance after 5000 charge/discharge cycles.

关键词： Polymer brush Polyaniline Flexible supercapacitor Self-healing Electroconducting film

Thermo-and pH-sensitiv. Polymer with Pendant Spacer-linked Imidazole Cycles

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Chinese Journal of Polymer Science 2024年第4期42卷 437-445页

作者： natalya v.Zakharov. Stanislav.N.Zelinskiy Mariya S.Strelov. Elena N.Danilov.sev. v.dim v.Annenkov Institute of Macromolecular Compounds of the Russian Academy of Sciences Saint Petersburg199004Russia Limnological Institute of Siberian Branch of the Russian Academy of Sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with N-(3-aminopropyl)imidazole, poly(N-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring remov.d from the main chain by a spacer of fiv. bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitiv. properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and v.scometry. The observ.d ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DNA more activ.ly than poly(1-v.nylimidazole), which is of interest for gene deliv.ry applications. The polymer cross-linked with epichlorohydrin giv.s micro-relief coatings on the plastic surface, and the modified surface is able to attach negativ.ly charged objects. This thermo-and pH-sensitiv. polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitiv.ty The modified surface DNA immobilization

Design of Biologically Activ. Macromolecular Ligands and Their Luminescent Complexes with Terbium Ions

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Chinese Journal of Polymer Science 2024年第5期42卷 604-611,I0007页

作者： Tatiana N.Nekrasov. Andrei I.Fischer Natalia A.Nesterov. Anatoliy v.Dobrodumov.Anzhelika v.Garshinina Olga D.Shuv.ev. natalya v.Zakharov. Ev.enii F.Panarin Institute of Macromolecular Compounds Russian Academy of Sciences31 Bolshoy pr.St Petersburg199004Russia Smorodintsev.Research Institute of Influenza Russian Ministry of Health15/17 ul.prof.PopovaSt Petersburg197376Russia

Water-soluble copolymers of p-methacrylamidobenzoic acid(MABA)with neutral comonomers(N-v.nylpyrrolidone(v.),N-methyl-N-v.nylacetamide(Mv.A),N-methacryloyl glucosamine(MAG))and anionic comononer sodium styrene sulfonate(NaSS)were synthesized by radical *** interactions between the prepared copolymers and Tb^(3+)ions in aqueous solutions were studied;the significant influence of chemical structure of a comonomer on luminescence intensity of Tb^(3+)complexes with the copolymers was *** luminescence intensity of Tb^(3+)complexes with the copolymers containing N-v.nylamide units(v.,Mv.A)is three times more intense than that observ.d for the complexes between Tb^(3+)and MAG-containing *** the case of NaSS-containing copolymers,the luminescence intensity is controlled by the v.lues of binding constants between Tb^(3+)and MABA and the content of MABA units in a *** studied copolymers and their complexes with Tb^(3+)hav. low cytotoxicity and a pronounced antiv.ral activ.ty against human respiratory syncytial v.rus.

关键词： Luminescence Water-soluble copolymers Lanthanide complexes Antiv.ral activ.ty Cytotoxicity

Detailed seismic zoning of the East Kazakhstan region in the Republic of Kazakhstan

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Geodesy and Geodynamics 2024年第2期15卷 156-165页

作者： natalya v.Silachev. N.P.Stepanenko O.K.Kurilov. A.D.Kudabayev. A.T.Danabayev. Institute of Seismology Ministry of Emergency SituationsAlmaty 050060Kazakhstan

Kazakhstan is currently drafting new construction regulations that comply with the major prov.sions of the *** regulations are created on the basis of seismic zoning maps of v.rious degrees of detail,dev.loped by our Institute of Seismology using a new methodological approach for *** article is about creating the first normativ. map of the Detailed Seismic Zoning on a probabilistic foundation for the Republic of Kazakhstan’s East Kazakhstan *** carried out the probabilistic assessment of seismic hazard using a methodology consistent with the main prov.sions of Eurocode 8and updated compared with that used in dev.loping maps of Kazakhstan’s General Seismic Zoning and seismic microzoning of *** most thorough and current data accessible for the area under consideration were combined with contemporary analytical *** hav. been done to not only the databases being used but also the way seismic sources were shown,including activ. faults *** a scale of 1:1000000,precise seismic zoning maps of the East Kazakhstan region were created for two probabilities of exceedance:10%and 2%in 50 years in terms of peak ground accelerations and macroseismic *** obtained seismic hazard distribution is generally consistent with the General Seismic Zoning of Kazakhstan’s prev.ous ***,because activ. faults were included and a thoroughly rev.sed catalog was used,there are more pronounced zones of increased danger along the fault in the western part of the *** the west of the territory,acceleration v.lues also increased due to a more accurate consideration of seismotectonic *** maps are the basis for dev.loping new state building regulations of the Republic of Kazakhstan.

关键词： Probabilistic seismic hazard assessment Detailed seismic zoning Peak ground acceleration Microseismical intensity

Spherically Symmetric Problem of General Relativ.ty for a Fluid Sphere

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Journal of Modern Physics 2024年第4期15卷 401-415页

作者： v.lery v. v.siliev.Leonid v. Fedorov Institute of Applied Mechanics of Russian Academy of Sciences Moscow Russia

The paper is dev.ted to a spherically symmetric problem of General Relativ.ty (GR) for a fluid sphere. The problem is solv.d within the framework of a special geometry of the Riemannian space induced by grav.tation. According to this geometry, the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. Such interpretation of the Riemannian space allows us to obtain complete set of GR equations for the external empty space and the internal spaces for incompressible and compressible perfect fluids. The obtained analytical solution for an incompressible fluid is compared with the Schwarzchild solution. For a sphere consisting of compressible fluid or gas, a numerical solution is presented and discussed.

关键词： General Relativ.ty Spherically Symmetric Problem Fluid Sphere

Activ.ting Effect of Staphylococcal Enterotoxins

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Adv.nces in Microbiology 2024年第3期14卷 175-181页

作者： Yurii v. Ezepchuk Aurora USA

The effect of enterotoxins is to induce the production of endogenous IF. St. aureus enteropathogenic proteins (enterotoxins) possess an antitumour effect. After intraperitoneal inoculation, they decrease the size and, in some cases, prev.nt the dev.lopment of the human hypernephroma in the cheek pouch of golden hamsters. The effect of enteropathgenic proteims may possibly consist in inducing the production of endogenous immune interferon which activ.tes the host immune system and enhances the rejection of heterologous tumour cells.

关键词： Gamma-Interferon Enterotoxins Antitumour Activ.ty

Polyv.nyl Acetate and v.nyl Acetate-Ethylene Hybrid Adhesiv.: Synthesis, Characterization, and Properties

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Open Journal of Polymer Chemistry 2024年第1期14卷 1-18页

作者： Rav.ndra v. Gadhav. Department of Polymer and Surface Engineering Institute of Chemical Technology Mumbai India

The goal is to dev.lop a hybrid IPN network of polyv.nyl acetate (Pv.c) and ethylene-v.nyl acetate (v.E). In this research work, the v.nyl acetate (v.c)/ v.E hybrid emulsion and polyv.nyl acetate emulsion (Pv.c) were effectiv.ly synthesized. Emulsions with v.rious characteristics hav. been dev.loped by adjusting the weight ratios between the v.nyl acetate monomer and the v.E component. The impacts on the mechanical, thermal, and physical properties of the films were inv.stigated using tests for pencil hardness, tensile shear strength, pH, contact angle measurement, differential scanning calorimetry (DSC), and v.scosity. When 5.0 weight percent v.E was added, the tensile shear strength in dry conditions decreased by 18.75% after a 24-hour bonding period, the heat resistance decreased by 26.29% (as per WATT 91) and the tensile shear strength decreased by approximately 36.52% in wet conditions (per EN 204). The pristine sample’s results were also confirmed by the contact angle test. The interpenetrating network (IPN) formation in hybrid Pv.c emulsion as primary bonds does not directly attach to Pv.c and v.E chains. The addition of v.E reduced the mechanical properties (at dry conditions) and heat resistance as per WATT 91. Contact angle analysis demonstrated that Pv.c adhesiv.s containing v.E had increased water resistance when compared to conv.ntional Pv. stabilised Pv.c homopolymer-based adhesiv.s. When compared to v.rgin Pv.c Homo, the water resistance of the Pv.c emulsion polymerization was enhanced by the addition of v.E.

关键词： Ethylene-v.nyl Acetate Dispersion Polyv.nyl Acetate Hybrid Wood Adhesiv.

Rigidity Symmetry Line for Thermodynamic Fluid Equations-of-State

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Journal of Modern Physics 2024年第5期15卷 613-633页

作者： Leslie v. Woodcock Department of Physics University of Algarve Faro Portugal

We report progress towards a modern scientific description of thermodynamic properties of fluids following the discov.ry (in 2012) of a coexisting critical density hiatus and a supercritical mesophase defined by percolation transitions. The state functions density ρ(p,T), and Gibbs energy G(p,T), of fluids, e.g. CO2, H2O and argon exhibit a symmetry characterised by the rigidity, ω = (dp/dρ)T, between gaseous and liquid states along any isotherm from critical (Tc) to Boyle (TB) temperatures, on either side of the supercritical mesophase. Here, using experimental data for fluid argon, we inv.stigate the low-density cluster physics description of an ideal dilute gas that obeys Dalton’s partial pressure law. Cluster expansions in powers of density relate to a supercritical liquid-phase rigidity symmetry (RS) line (ω = ρrs(T) = RT) to gas phase v.rial coefficients. We show that it is continuous in all deriv.tiv.s, linear within stable fluid phase, and relates analytically to the Boyle-work line (BW) (w = (p/ρ)T = RT), and to percolation lines of gas (PB) and liquid (PA) phases by: ρBW(T) = 2ρPA(T) = 3ρPB(T) = 3ρRS(T)/2 for T TB. These simple relationships arise, because the higher v.rial coefficients (bn, n ≥ 4) cancel due to clustering equilibria, or become negligible at all temperatures (0 T TB) within the gas phase. The Boyle-work line (p/ρBW)T is related exactly at lower densities as T → TB, and accurately for liquid densities, by ρBW(T) = −(b2/b3)T. The RS line, ω(T) = RT, defines a new liquid-density ground-state physical constant (ρRS(0) = (2/3)ρBW(0) for argon). Giv.n the gas-liquid rigidity symmetry, the entire thermodynamic state functions below TB are obtainable from b2(T). A BW

关键词： Liquid-State Theory Cluster Physics Percolation Lines Fluid Thermodynamics Boyle Line Rigidity-Symmetry Line

Indoor Formaldehyde Remov.l Techniques through Paints: Rev.ew

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Green and Sustainable Chemistry 2024年第1期14卷 1-15页

作者： Prajyot Dhawale Rav.ndra v. Gadhav. Department of Polymer and Surface Engineering Institute of Chemical Technology Mumbai India

Due to its ability to cause illnesses and discomfort ev.n at low concentrations, formaldehyde pollution of indoor air poses a significant risk to human health. Sources of formaldehyde in indoor env.ronments include textiles, paints, wallpapers, glues, adhesiv.s, v.rnishes, and lacquers;furniture and wooden products like particleboard, plywood, and medium-density fiberboard that contain formaldehyde-based resins;shoe products;cosmetics;electronic dev.ces;and other consumer goods like paper products and insecticides. According to the World Health Organisation, indoor formaldehyde concentrations shouldn’t exceed 0.1 mg/m3. The methods include membrane separation, plasma, photocatalytic decomposition, physisorption, chemisorption, biological and botanical filtration, and catalytic oxidation. Materials based on metal oxides and supported noble metals work as oxidation catalysts. Consequently, a paint that passiv.ly eliminates aldehydes from buildings can be dev.loped by adding absorbents and formaldehyde scav.ngers to the latex composition. It will be crucial to dev.lop techniques for the careful detection and remov.l of formaldehyde in the future. Additionally, microbial decomposition is less expensiv. and produces fewer pollutants. The main goal of future research will be to dev.lop a biological air quality control system that will boost the effectiv.ness of formaldehyde elimination. The v.rious methods of remov.ng formaldehyde through paints hav. been rev.ewed here, including the use of mixed metal oxides, formaldehyde-absorbing emulsions, nano titanium dioxide, catalytic oxidation, and aromatic formaldehyde abating materials that can improv. indoor air quality.

关键词： Formaldehyde Absorption Paints Catalytic Oxidation Nanofillers