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Polyelectrolyte Complexes between Hyperbranched and Linear Polysaccharides: Fucoidan/Chitosan

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Chinese Journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekaterina R.Gasilova Daria n.Poshina Aleksandra O.Sitnikova natalia n.Saprykina yury A.Skorik Institute of Macromolecular Compounds of the Russian Academy of Sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbranched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/L acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—OSO3 groups and 5 wt%of uronic acid units,it was a“strong-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/L AcOH and open branched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shrank;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC branches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/L AcOH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole range of FUC content(10 wt%nning electron microscopy and atomic force microscopy images of dried samples were discussed in relation to the light scattering results.

关键词： Polyelectrolyte complexes Chitosan Hyperbranched fucoidan Light scattering

Peculiarities of Ethylene Polymerization Reactions with Bis(imino)pyridyl Complexes of CoCl_(2) and FeCl_(2)

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Chinese Journal of Polymer Science 2024年第4期42卷 492-500页

作者： Laura A.Rishina yury V.Kissin Svetlana S.Lalayan Artem A.Antonov Vadim G.Krasheninnikov Alexander A.Gulin n.n.Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences4 Kosygin St.Moscow119991Russia Department of Chemistry and Chemical Biology RutgersThe State University of New Jersey123 Bevier Rd.PiscatawayNJ08854USA Boreskov Institute of Catalysis Russian Academy of Sciences5 Lavrentieva Prosp.Novosibirsk630090Russia

The article describes ethylene polymerization reactions with transition metal catalysts based on complexes of CoCl_(2) and FeCl_(2) with an n,n,n-tridentate ligand 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine. The complexes are converted into polymerization catalysts by reacting them either with polymethylalumoxane (MAO) or with a combination of Al(C2H5)2Cl and Mg(C4H9)2 at an [Al]:[Mg] ratio of ~3. Both MAO-activated complexes readily polymerize ethylene at 35 ℃ with the formation of linear, low molecular weight polymers with a narrow molecular weight distribution. The same complexes, when activated with the Al(C2H5)2Cl-Mg(C4H9)2 combination, form multi-center catalysts and generate polyethylenes with a broad molecular weight distribution.

关键词： Ethylene polymerization Bis(imino)pyridyl complexes of CoCl_(2)and FeCl_(2) Molecular-weight distribution Polymer chain structure

Degenerations of Jordan Algebras and“Marginal”Algebras

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Algebra Colloquium 2021年第2期28卷 281-294页

作者： Ilya Gorshkov Ivan Kaygorodov yury Popov Sobolev Institute of Mathematics NovosibirskRussia Universidade Federal do ABC CMCCSanto AndreBrazil Universidade Estadual de Campinas CampinasBrazil

We describe all degenerations of the variety ■3 of Jordan algebras of dimension three over *** particular,we describe all irreducible components in ■*** every n we define an n-dimensional rigid“marginal”Jordan algebra of level ***,we discuss marginal algebras in associative,alternative,left alternative,non-commutative Jordan,Leibniz and anticommutative cases.

关键词： Jordan algebra degeneration rigid algebra irreducible component marginal algebra

Quantum fluids in nanoporous media——Effects of the confinement and fractal geometry

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Chinese Science Bulletin 2011年第34期56卷 3617-3622页

作者： TAYURSKII Dmitrii LYSOGORSKIY yury Department of Physics Kazan Federal University

The complex behavior of such quantum fluids like liquid 4He and liquid 3He in nanoporous media is determined by spatial quantization because of geometrical confinement as well as by significant contribution from the surface atoms. In the present report we will review the procedure, results and discuss the issues for fractionalized nonextensive hydrodynamical approach to describe the properties of quantum fluids inside nanopores and propose consideration of strong correlated quantum liquid by means of fractionalized Schro¨dinger equation.

关键词：量子流体多孔介质分形几何薛定谔方程复杂行为报告审查力学方法量子液体

MXenes-The fastest growing materials family in the two-dimensional world

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Chinese Chemical Letters 2020年第4期31卷 919-921页

作者： Bin Xu yury Gogotsi State Key Laboratory of Organic-Inorganic Composites Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing 100029China A.J.Drexel nanomaterials Institute Department of Materials Science States and EngineeringDrexel UniversityPhiladelphiaPA 19104United States

The structural and compositional variety combined with tunable surface characteristics have rendered MXenes as one of the most versatile 2D material families with numerous rapidly expanding application *** are typically synthesized by selective etching of layered carbide and nitride precursors,such as MAX phases,which have the general formula Mn+1AXn(n=1-4),where M is an early transition metal.

关键词： MXene render carbide

Two-dimensional MXenes and their applications

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Frontiers of physics 2023年第1期18卷 1-5页

作者： Guangcun Shan Zejian Ding yury Gogotsi School of Instrumentation Science and Opto-electronics Engineering Beihang UniversityBeijing 100091China Institute of Experimental Physics Saarland University66123 SaarbrückenGermany A.J.Drexel nanomaterials Institute and Department of Materials Science and EngineeringDrexel UniversityPhiladelphiaPA 19104USA

Two-dimensional(2D)transition metal carbides,nitrides or carbonitrides(MXene)have attracted tremendous attention as a potentially the largest family of inorganic *** have a general formula Mn+1XnTx,where M is an early transition metal(2 or more can be present in a random mix or a specific order),X is C and/or n elements(oxygen can partially substitute),and T_(x)(x is variable)represent surface terminations,which can include reactive end groups(such as–OH and=O),halogens and chalcogens,and n can vary from 1 to 4(fractions are possible).All MXenes can either be produced as multilayer particles(ml-MXene)or delaminated(d-MXene)single-layer flakes.

关键词： materials. carbonitride dimensional

An aqueous 2.1 V pseudocapacitor with MXene and V-MnO_(2) electrodes

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nano Research 2022年第1期15卷 535-541页

作者： Jiabin Wu Qun Li Christopher E.Shuck Kathleen Maleski Husam n.Alshareef Jun Zhou yury Gogotsi Liang Huang Wuhan national Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Department of Materials Science and Engineering and A./.Drexel nanomaterials Institute Drexel UniversityPhiladelphiaPennsylvania 19104USA Materials Science and Engineering Physical Science and Engineering DivisionKing Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

MXenes have shown record-breaking redox capacitance in aqueous electrolytes,but in a limited voltage window due to oxidation under anodic potential and hydrogen evolution under high cathodic *** Ti3C2Tx Xene negative electrode with RuO_(2) or carbon-based positive electrodes expanded the voltage window in sulfuric acid electrolyte to about 1.5 ***,we present an asymmetric pseudocapacitor using abundant and eco-friendly vanadium doped MnO_(2) as the positive and Ti_(3)C_(2)Tx MXene as the negative electrode in a neutral 1M Li2SO4 *** all-pseudocapacitive asymmetric device not only uses a safer electrolyte and is a much less expensive counter-electrode than RuO_(2),but also can operate within a 2.1 V voltage window,leading to a maximum energy density of 46 Wh/*** study also demonstrates the possibility of using MXene electrodes to expand the working voltage window of traditional redox-capable materials.

关键词： MXene pseudocapacitors metal oxides supercapacitors manganese oxide

Possible therapeutic targets and promising drugs based on unsymmetrical hetaryl-substituted porphyrins to combat SARS-CoV-2

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Journal of Pharmaceutical Analysis 2021年第6期11卷 691-698页

作者： yury A.Gubarev natalya Sh.Lebedeva Elena S.Yurina Sergey A.Syrbu Aleksey n.Kiselev Mikhail A.Lebedev G.A.Krestov Institute of Solution Chemistry of the Russian Academy of Sciences 153045IvanovoRussia Ivanovo State University of Chemistry and Technology 153000IvanovoRussia

Coronavirus disease 2019 is a serious disease that causes acute respiratory syndrome and negatively affects the central nervous *** acute respiratory syndrome coronavirus 2(SARS-CoV-2)crosses the blood-brain barrier due to the spike(S) protein on the surface of the viral ***,it is important to develop compounds that not only have an inhibitory effect but are also capable of completely deactivating the S protein *** study describes the purposeful modification of porphyrins and proposes compounds,asymmetrically hetaryl-substituted porphyrins with benzothiazole,benzoxazole,and n-methylbenzimidazole residues,to deactivate the S protein *** docking of SARS-CoV-2 proteins with hetaryl-substituted porphyrins showed that the viral S protein,nucleocapsid(n) protein,and non-structural protein 13(nsp13) exhibited the highest binding ***-substituted porphyrins form strong complexes(13-14 kcal/mol) with the receptor-binding domain of the S protein,while the distance from the porphyrins to the receptor-binding motif(RBM)does not exceed 20 ?;therefore,RBM can be oxidized by ^(1)O_(2),which is generated by *** porphyrins interact with the n protein in the serine/arginine-rich region,and a number of vulnerable amino acid residues are located in the photooxidation *** damage complicates the packaging of viral RnA into new ***-energy binding of hetaryl-substituted porphyrins with the n-and C-terminal domains of nsp13 was *** binding blocks the action of nsp13 as an enzyme of exoribonuclease and methyltransferase,thereby preventing RnA replication and processing.A procedure for the synthesis of hetaryl-substituted porphyrins was developed,new compounds were obtained,their structures were identified,and their photocatalytic properties were studied.

关键词： Porphyrins SARS-CoV-2 Molecular docking Photoinactivation

Probiotics and autoprobiotics for treatment of Helicobacter pylori infection

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World Journal of Clinical Cases 2023年第20期11卷 4740-4751页

作者： natalia V Baryshnikova Anastasia S Ilina Elena I Ermolenko yury P Uspenskiy Alexander n Suvorov Department of Molecular Microbiology Institute of Experimental MedicineSt.Petersburg 197376Russia Internal Diseases Department of Stomatological Faculty Pavlov First St-Petersburg State Medical UniversitySt.Petersburg 197022Russia Laboratory of Medical and Social Pediatric Problems St-Petersburg State Pediatric Medical UniversitySt.Petersburg 194100Russia Clinical Department Institute of Experimental MedicineSt.Petersburg 197376Russia Department of Faculty Therapy named After V.A.Valdman St-Petersburg State Pediatric Medical UniversitySt.Petersburg 194100Russia

The article discusses various approaches for probiotic treatment of Helicobacter pylori(***)infection:Probiotics as an adjuvant treatment in the standard eradication therapy;probiotic strains as a monotherapy;and autoprobiotics as a *** refer to indigenous bifidobacteria,lactobacilli,or enterococci isolated from a specific individual,intended to restore his/her microbiota and improve his/her *** potential mechanisms of probiotic action against *** include correction of the gut microbiota,immunological effects(enhancement of humoral and cellular immunity,and reduction of oxidative stress),direct antagonistic effects against ***(such as colonization resistance and bacteriocin synthesis),and stimulation of local immunological protection(strengthening of the mucous protective barrier and reduction of gastric mucosa inflammation).The incorporation of probiotics into comprehensive eradication therapy shows promise in optimizing the treatment of *** *** can enhance the eradication rates of ***,reduce the occurrence and severity of side effects,and improve patient *** or autoprobiotic monotherapy can be considered as an alternative treatment approach in cases of allergic reactions and insufficient effectiveness of *** recommend including probiotics as adjunctive medications in *** ***,further randomized multicenter studies are necessary to investigate the effects of probiotics and autoprobiotics against ***,in order to gain a better understanding of their mechanisms of action.

关键词： Helicobacter pylori Probiotic Autoprobiotic Eradication Microbiota Gut Immunity