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

作者： Elizaveta v.Batishcheva Nikolay N.Smirnov natal.a v.bobrova Maria P.Sokolova 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 conductivity of the membranes reaches 1.5 and 3.1 mS·cm^(-1)(60 ℃ and 98% relative humidity) when they are saturated with water or H_2SO_4(1 mol·L^(-1)) electrolyte,respectively. 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 achieved at current density 1 A·g^(-1). Retaining of 90% of initial capacitance after 10000 of charge-discharge cycles proves high electrochemical stability of prepared ICM.

关键词： Bacterial cellulose Ion conductivity Porous membrane Supercapacitor

Self-healable and Robust Film Based on Electroactive 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.Sokolova vitaly K.vorobiov Nikolay N.Smirnov Ivan S.Kuryndin natal.a v.bobrova Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

The aim of this study was to develop self-healable and robust elect roconductive film based on polyaniline copolymer for application as electrode in flexible *** this purpose,the electroconductive polymer brushes(EPB)was *** synthesis of EPB is based on graft polymerizations of acrylamide(AAm)on poly(vinyl alcohol)(PvA)with formation of PvA-PAAm polymer brush and subsequent graft copolymerization of aniline and p-phenylenediamine on PvA-PAAm resulting in formation of EPB with electroconducting copoly(aniline-co-pphenylenediamine)(PAPh DA).It was found that the ratio between PvA 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 reveal more uniform distribution of PAPhDA in EPB in comparison with reference PvA-PAPhDA and PAAm-PAPhDA *** was demonstrated that mechanical cha racteristics and electrical conductivity values of films restore at large extent after curring and self-healing under optimal relative humidity level(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

Synergistic effect of chitin nanofibers and polyacrylamide on electrochemical performance of their ternary composite with polypyrrole

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Journal of Energy Chemistry 2018年第3期27卷 843-853页

作者： Michael A.Smirnov Maria P.Sokolova natal.a v.bobrova Alexander M.Toikka Pierfrancesco Morganti Erkki Lahderanta Lappeenranta University of Technology 53850 LappeenrantaFinland Institute of Macromolecular compounds Russian Academy of Sciences199004 Saint PetersburgRussia St.Petersburg State University PeterhofSaint Petersburg 198504Russia Dermatological Institute II University of Naples80138 NaplesItaly

Development of simple methods for preparation of polymeric electrode materials with nanofibrous network structure is a perspective way toward cheap supercapacitors with high specific capacitance and energy density. In this work one-pot synthesis of electroactive ternary composite based on polypyrrole, polyacrylamide and chitin nanofibers with beneficial morphology was elaborated. Ternary system demonstrates better electrochemical performance in comparison with both polypyrrole–polyacrylamide and polypyrrole–chitin binary composites. Possible mechanism of synergistic effect of simultaneous influence of polyacrylamide and chitin nanofibers on the formation of composite＇s structure is *** highest attained specific capacitance of electroactive polypyrrole in ternary composite reached 249 F/g at 0.5 A/g and 150 F/g at 32 A/g. Symmetrical supercapacitor was assembled using the elaborated electrode material. High specific capacitance 89 F/g and good cycling stability with capacitance retention of 90% after 3000 cycles at 2 A/g were measured.

关键词： Energy materials Nanocomposites Natural fibers Electrical properties

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Current Zoology 2024年第1期70卷 1-12页

作者： Lucia v.Sommaro Juan J.Martinez Marina B.Chiappero Andrea R.Steinmann Cristina N.Gardenal JoséW.Priotto Laboratorio de Ecologia Evolutiva y Biogeografia Instituto de Ecorregiones Andinas(INECoA)Universidad Nacional de Jujuy-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)San Salvador de JujuyJujuyArgentina Instituto de Diversidad y Ecologia Animal(IDEA) Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)and Universidad Nacionalde CordobaCordobaArgentina Catedra de Genética de Poblaciones y Evolucion Facultad de Ciencias ExactasFisicas y NaturalesUniversidad Nacional de CordobaCordobaArgentina Grupo de Investigaciones en Ecologia Poblacional y Comportamental(GIEPCO) Instituto de Ciencias de la TierraBiodiversidad y Ambiente(ICBiA)Universidad Nacional de Rio Cuarto-Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)Rio CuartoCordobaArgentina

The sex-biased dispersal and kinship dynamics are important factors shaping the spatial distribution of individuals and are key parameters affecting a variety of ecological and evolutionary ***,we studied the spatial distribution of related individuals within a population of corn mice Calomys musculinus in a seasonal cycle to infer dispersal *** sampling was carried out from spring 2005 to winter 2006 in field borders of intensively managed *** data from 346 individuals with 9 microsatellites showed spatial genetic structure was weak for males,but not for *** results indicate a complex spatial kinship dynamic of related females across all ***,contrary to our expectations,dispersal distances decrease with the increase of the population ***,male dispersal distances were greater when population abundance increased and thus the availability of active *** disperse greater distances to mate and sire offspring with distant females as a possible inbreeding avoidance *** study shows that *** is capable of much greater scattering distances than previously reported and that dispersal occurs fluidly and without barriers across the *** indirect benefit of dispersal on individual fitness could be related to relaxing the competition in the natal.area and increasing the mating *** study highlights the value of combining genetic relatedness,fieldwork observations,and behavioral data to estimate dispersal at a fine geographical scale.

关键词： dispersal distances kinship dynamics microsatellite small mammals spatial autocorrelation

Long-Term Impact of Acute Retinoic Acid Supplementation at the Young Age on Testicular Architecture of Wistar Albino Rats

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Advances in Reproductive Sciences 2024年第1期12卷 1-13页

作者： Mama Sy Racha Kamenda Ibondou Fatoumata Bah Robert Foko Ndiaga Diop Mame vénus Abdoulaye Séga Cheikh Diop Mamadou Fall Oumar Faye Laboratory of Histology Embryology and Cytogenetics Faculty of Medecine Cheikh Anta Diop University Dakar Senegal

Introduction: Inappropriate and excess vitamin supplementation, particularly for vitamin A, is increasingly recognized as a public health problem in developed countries. On the other hand, blind supplementation of vitamin A, for children in developing countries is a subject of controversy in the literature. The crucial role of vitamin A in the process of spermatogenesis in adult rodents is well established, but only a few publications are consecrated to the long-term effect of vitamin A intake at a young age on testicular development and differentiation. Objectives: Our study aimed to evaluate the long-term effects of acute supplementation at an early age, in the post-natal period, on spermatogenesis and testicular trophicity at adult age. Material and Methods: Young Wistar Albinos rats of 22 days received an acute high dose of supplementation of vitamin A (retinyl palmitate). The control group, group 1, received only extra virgin olive oil, Group 2 a dose of 7000 IU/kg of retinyl palmitate, group 3, 14,000 IU/kg, and Group 4 a dose of 28,000 IU/kg. At 10 weeks of age, the testes’ testosterone levels were measured by ELISA. For histological assessment, sections were stained with Hematoxylin eosin, and the Johnsen score was used to evaluate spermatogenesis in the seminiferous tubules. Results: The average testicular weights of rats were significantly lower in group 4 (p vel in the testis compared to the control group (p .01). Most of the seminiferous tubules were concerned by an arrest of spermatogenesis and the Johnsen score was decreased with a mean score of 5.96 ± 1.60 (p .001) in that Group. In Group 3, Johnsen’s score was significantly better than the one obtained with the control. Conclusion: We observed a negative effect in the long term with a high acute dose of supplementation of retinyl palmitate at a young age, on testicular development and differentiation. Despite a return to normal diet after that supplementation, d

关键词： vitamin A Retinyl Palmitate Spermatogenesis Testis-Wistar Albino Rats

Radial density profile and stability of capillary discharge plasma waveguides of lengths up to 40 cm

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High Power Laser Science and Engineering 2021年第2期9卷 31-40页

作者： M.Turner A.J.Gonsalves S.S.Bulanov C.Benedetti N.A.bobrova v.A.Gasilov P.v.Sasorov G.Korn K.Nakamura J.van Tilborg C.G.Geddes C.B.Schroeder E.Esarey Lawrence Berkeley National Laboratory BerkeleyCAUSA Keldysh Institute of Applied Mathematics RAS MoscowRussia ELI Beamlines DolníBˇrežanyCzech Republic

We measured the parameter reproducibility and radial electron density profile of capillary discharge waveguides with diameters of 650µm to 2 mm and lengths of 9 to 40 *** the best of the authors’knowledge,40 cm is the longest discharge capillary plasma waveguide to *** length is important for≥10 Gev electron energy gain in a single laser-driven plasma wakefield acceleration *** of waveguide parameter variations showed that their focusing strength was stable and reproducible toverage on-axis plasma electron density tovariations explain only a small fraction of laser-driven plasma wakefield acceleration electron bunch variations observed in experiments to *** of laser pulse centroid oscillations revealed that the radial channel profile rises faster than parabolic and is in excellent agreement with magnetohydrodynamic simulation *** show that the effects of non-parabolic contributions on Gaussian pulse propagation were negligible when the pulse was approximately matched to the ***,they affected pulse propagation for a non-matched configuration in which the waveguide was used as a plasma telescope to change the focused laser pulse spot size.

关键词： capillary plasma waveguide laser-driven plasma wakefield acceleration plasma telescope matched laser guiding

Linking sedimentary provenance,climate and tectonics in the Neoproterozoic SeridóBelt,Borborema Province(NE Brazil)

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Geoscience Frontiers 2023年第6期14卷 414-431页

作者： Carlos v.A.Ribeiro Marcos C.C.Sales Armando L.S.de Oliveira Ricardo Sallet Programa de Pós-graduação em Geologia Instituto de GeociênciasUniversidade de Brasília(UnB)CEP 70910-900 BrasíliaDFBrazil Programa de Pós-Graduação em Geociências Universidade Federal de PernambucoDepartamento de GeologiaCentro de Tecnologia e GeociênciasAv.da ArquiteturaCEP 50740-530 RecifePEBrazil Departamento de Geologia Universidade Federal do Rio Grande do NorteCEP 59078-970 NatalRNBrazil

The SeridóBelt,at the extreme northeast of Brazil,is one of the several Neoproterozoic mobile belts related to the Brasiliano/Pan-African Orogeny in Western *** lithostratigraphy of the SeridóBelt comprises basal quartzites and metaconglomerates(Equador Formation)overlain by hornblende-bearing paragneisses,calc-silicate rocks and marbles(Jucurutu Formation)and biotiteschists(SeridóFormation).We investigated the sedimentary provenance of these rocks based on an integration of compiled whole-rock geochemistry,Sm-Nd isotopes,U-Pb detrital zircon ages and a new set of whole-rock trace elements *** Formation quartzites have major and trace elements patterns that resemble cratonic sandstones,with a typical felsic provenance consistent with the isotopic composition of plutonic Archean to Paleoproterozoic basement *** proxies suggest that these rocks were deposited in fresh waters under anoxic conditions and moderate to intense weathering conditions(CIA=58–79).A shift in provenance led to an increase in intermediate-mafic sources during the deposition of the Jucurutu and Seridó*** elements from rock types in these units are nearly identical,yet they differ on the contents of some high field-strength elements(e.g.,Sc,v and Ni),which are higher in the SeridóFormation than average *** proxies show similar depositional environments,with brackish to marine conditions for the Jucurutu and Seridóformations under anoxic to euxinic *** conditions are consistently lower in the Jucurutu Formation(CIA=58–66)in comparison with the SeridóFormation(CIA=60–88).Compiled U-Pb data suggest maximum depositional ages of 633±11 Ma and 633±6 Ma for Jucurutu and Seridóformations,respectively,suggesting deposition following the ca.645–635 Ma Marinoan *** compared the geochemistry of the SeridóFormation schists with currently exposed basement rocks and showed a strong affinity with Neoproterozoic arc-related

关键词： Whole-rock geochemistry Marinoan Glaciation U-Pb detrital zircon Brasiliano Orogeny

Prenatal radiographic evaluation of congenital transverse limb deficiencies:A scoping review

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World Journal of Orthopedics 2023年第3期14卷 155-165页

作者： Neeraj vij Luis F Goncalves Aaron Llanes Sean Youn Mohan v Belthur Department of Orthopedic Surgery Phoenix Children’s HospitalPhoenixAZ 85016United States Department of Radiology Phoenix Children's HospitalPhoenixAZ 85016United States Department of Orthopedics University of Arizona College of Medicine-PhoenixPhoenixAZ 85004United States

BACKGROUND Congenital transverse deficiencies are horizontal deficiencies of the long bones that occur with a reported incidence as high 0.38%.They can occur alone or represent a manifestation of a various clinical *** has tradi-tionally comprised of conventional radiography and prenatal imaging *** has been much advancement regarding prenatal imaging modalities to allow for early diagnosis and appropriate *** To summarize the current state of knowledge on congenital transverse limb deficiencies and to provide an update regarding the radiographic evaluation of congenital transverse limb *** This IRB-exempt scoping review followed the PRISMA-ScR checklist for scoping reviews *** search engines were searched for a total of 265 *** authors reviewed these during the screening *** these,51 studies were included in our *** magnetic resonance imaging(MRI),3D Ultrasound,and multidetector Computed tomography(CT)exist are emerging modalities that have the potential to improve *** Use of the appropriate classification system,three-dimensional ultrasonography with a maximum intensity projection,and appropriate use of prenatal MRI and prenatal CT can improve diagnosis and inter-provider *** Further scholarly efforts are required to develop improve standardized guidelines regarding the pre-natal radiographic evaluation of congenital limb deficiencies.

关键词： Terminal deficiencies Roentgenographic evaluation Pediatric skeletal deficiencies Early diagnosis Patient-centered care Prenatal imaging©The Author(s)2023.Published by Baishideng Publishing Group Inc.All rights reserved.

Red-emitting CaWO4:Eu^(3+),Tm^(3+)phosphor for solid-state lighting:Luminescent properties and morphology evolution

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Journal of Rare Earths 2022年第2期40卷 226-233,I0002页

作者： L.X.Lovisa I.M.P.da Silva A.A.G.Santiago M.Siu Li E.Longo C.A.Paskocimas M.R.D.Bomio F.v.Motta Institute of Physics and Chemistry.Federal University of Itajubd(UNIFEI) ItajubdMG37500-903Brazil LSQM-Laboratory of Chemical Synthesis of Materials-Department of Materials Engineering Federal University of Rio Grande Do NorteP.O.Box 152459078-900Natal RNBrazil IFSC USPAv.Trabalhador Sao Carlense400CEP 13566-590Sao CarlosSPBrazil CDMF-LIEC UFSCarP.O.Box 67613565-905Sao Carlos.SPBrazil

CaWO_(4):xEu^(3+),yTm^(3+)crystals were obtained by facile synthesis at low temperature by the microwaveassisted hydrothermal method(MAH).The phase formation,morphology,luminescent properties and ene rgy transfer were *** X-ray diffraction(XRD)re sults show the formation of a scheelitelike tetragonal structure without the presence of secondary *** growth mechanism of hierarchical micro structures based on self-assembly and Ostwald-ripening processes was evaluated,obtaining different types of *** luminescence spectra of CaWO_(4):Eu^(3+),Tm^(3+)at 325 nm excitation show the predominance of red emission at the 5 D0→7 F2(Eu^(3+))transition at 624 *** feature signals dominant behavior of the electric dipole *** presence of Tm^(3+)is notably evident in the absorption spectra by the related excitation transitions:3 H6→1 G4,3 H6→3 F3 and 3 H6→3 *** parameters are discussed to characterize CaWO_(4):Eu^(3+),Tm^(3+)*** study of the emission spectrum as a function of the concentration of Eu^(3+)(x mol%)and Tm^(3+)(y mol%)indicates that the CaWO_(4):Eu^(3+),Tm^(3+)phosphors show stronger red emission intensity and exhibit the CIE value of x=0.63 and y=*** photoluminescence results show 97%high color purity for CaWO_(4):4 mol%Eu^(3+),a high CRI(92%)and a low CCT of 1085 *** results demonstrate that the CaWO_(4):Eu^(3+),Tm^(3+)red phosphors are promising as color converters for application in white light-emitting diodes and display devices.

关键词： CaWO_(4):Eu^(3+),Tm^(3+)microwave-assisted hydrothermal method Photoluminescence Red phosphor Rare earths

A novel protocol for reviving of oil and natural gas wells

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Petroleum Research 2019年第3期4卷 276-281页

作者： R.v.v.Ramana Murthy Naresh Kumar Katari N.Satya Sree Sreekantha B.Jonnalagadda Division of Chemistry Vignan's Foundation for ScienceTechnology and Research UniversityVadlamudiGuntur 522213 Andhra PradeshIndia Department of Chemistry GITAM deemed to be UniversityHyderabad502329TelanganaIndia School of Chemistry&Physics Westville CampusUniversity of KwaZulu-NatalP Bag X 54001Durban 4000South Africa

For effective cleaning of oil and gas wells and their revival,a novel fluid composition of enzyme-G with acid mixture together with corrosion inhibitor and selected additives is *** and field experiments endorse the effectiveness of the new fluid *** testing and analyzing the results with various treatment combinations,the procedure is *** efficacy is validated by treating various oil and natural gas *** communication provides a comprehensive description of the method for cleaning the oil and gas wells and their stimulation for improving the *** novel enzymes-G composition developed,effectively removes the impurities from the face of the wellbore,improve pore formation and create additional artificial channels to enhance the production of oil and *** developed protocols could also be used in injection wells to improve the injection rates.

关键词： Well stimulation Polymers breaking Acidization Fragmentation Corrosion inhibitor Enzyme G