检索结果-南通市图书馆

Thermo-and pH-sensitive Polymer with Pendant Spacer-linked Imidazole Cycles

在线全文

学校读者我要写书评

暂无评论

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

作者： Natalya v.Zakharova Stanislav N.Zelinskiy mariya S.Strelova Elena N.Danilovtseva vadim 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 removed from the main chain by a spacer of five bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13C-NmR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and viscometry. The observed 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 actively than poly(1-vinylimidazole), which is of interest for gene delivery applications. The polymer cross-linked with epichlorohydrin gives micro-relief coatings on the plastic surface, and the modified surface is able to attach negatively charged objects. This thermo-and pH-sensitive polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitivity The modified surface DNA immobilization

Hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第5期88卷 239-265页

作者： Boris I.Kharisov Oxana v.Kharissova Lucy T.González Yolanda Peña méndez Igor E.Uflyand Idalia Gómez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico Department of Chemistry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials *** particular,carbon allotropes are widely used in these composites being widely applied for medical *** a gap of insufficient generalization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and *** composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,*** composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CvD,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling,3D printing,electrospinning,and lyophilisation,among *** of various synthesis techniques can be also carried out for composite *** or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from *** biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic *** these composites,especially with O-containing functionalizing groups,HA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,chemical stability and biocompatibility,as well as possessing antibacterial ***→G reduction and higher HA decoration were obs

关键词： Hydroxyapatite Carbon nanotubes Graphene Quantum dots Fullerenes Nanodiamonds

Exploring the potential of drill cuttings for reservoir characterization:A case study from the volga-Ural basin,Russia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Research 2024年第2期9卷 193-205页

作者： Ibrahem Yousef v.P.morozov Kazan Federal University Institute of Geology and Petroleum Technologies420008Russian Federation

The research objectives are to assess the possibility of using drill cutting analysis to obtain information about the mineralogical and geochemical properties of the reservoir *** cutting samples were collected from a vertical well that penetrated the Domanik sediments(Semiluksk Formation)in one of the oil fields in the volga-Ural petroleum *** sections from drill cuttings were examined using an optical polarizing microscope(Axio Imager A2).X-ray diffraction(XRD)analyses were performed using a Brucker D2 Phaser X-ray powder *** properties were studied using an STA 449 F3 Jupiter *** pyrolytic studies were performed using the Rock-Eval *** inspection showed that the studied sediments are alternations of carbonates and siliceous-carbonate *** section examinations revealed that the carbonates are mainly limestone(mudstone and wackestone)and are characterized by a dense texture and up to 30%organic *** siliceous-carbonate rocks are dominated by siliceous mudstones and are characterized by dark colours,layered structure,and an enrichment in organic *** analyses showed that the carbonate rocks are mainly composed of calcite,dolomite,quartz,feldspar,and mica,which are minor *** siliceous-carbonate rocks are dominated by quartz,followed by calcite,although they also contain feldspars,mica,dolomite,and pyrite as *** to the simultaneous thermal analysis,the average total hydrocarbon in the carbonate and siliceous-carbonate rocks is 13.6%(for the core samples)and 11.5%(for the drill cutting samples).The content of heavy hydrocarbons in the rocks is higher than the content of light hydrocarbons,indicating the immature nature of organic *** is found sporadically in siliceous-carbonate *** to the pyrolytic studies,average S1 is 4.4 mg/g and average S2 is 19.8 mg/g(for the core samples);average S1 is 2.1 mg/g and average S2 is 17.8 mg/g(for the

关键词： Drill cuttings Reservoir characterization Domanik Semiluksk volga-Ural Russia

Preface–Introduction to the Special Issue for Chinese-Russian Workshop on Biophotonics and Biomedical Optics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Innovative Optical Health Sciences 2024年第5期17卷 1-3页

作者： Tingting Yu Dan Zhu valery v.Tuchin Britton Chance Center for Biomedical Photonics-moE Key Laboratory for Biomedical Photonics Advanced Biomedical Imaging FacilityWuhan National Laboratory for Optoelectronics–Advanced Biomedical Imaging FacilityHuazhong University of Science and TechnologyWuhan 430074China Department of Optics and Biophotonics Science Medical CenterSaratov State UniversitySaratov 410012Russia Laboratory of Laser Diagnostics of Technical and Living Systems Institute of Precision Mechanics and ControlFRC“Saratov Scientic Centre of the Russian Academy of Sciences”Saratov 410028Russia Laboratory of Laser molecular Imaging and machine Learning Tomsk State UniversityTomsk 634050Russia

The Chinese-Russian Workshop on Biophotonics and Biomedical Optics 2023 was held online twice on 18–21 September and 25–26 September *** bilateral workshop brought together both Russian and Chinese scientists,engineers,and clinical researchers from a variety of disciplines engaged in applying optical science,photonics,and imaging technologies to problems in biology and *** the workshops,two plenary lectures and twenty invited presentations were *** special issue selects some papers from both Russian and Chinese sides,consisting of one review and seven original research articles.

关键词： Russian photonics Biomedical

Nonlinear-Optical Analogies in Nuclear-Like Soliton Reactions:Selection Rules,Nonlinear Tunneling and Sub-Barrier Fusion–Fission

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2024年第8期41卷 1-7页

作者： T.L.Belyaeva v.N.Serkin Universidad Autonoma del Estado de mexico Av.Instituto Literario 100C.P.50000TolucaMexico Benemerita Universidad Autonoma de Puebla Av.4 Sur 104C.P.72001PueblaMexico

The main goal of our study is to reveal unexpected but intriguing analogies arising between optical solitons and nuclear physics,which still remain hidden from *** consider the main cornerstones of the concept of nonlinear optics of nuclear reactions and the well-dressed repulsive-core *** the base of this model,we reveal the most intriguing properties of the nonlinear tunneling of nucleus-like solitons and the soliton selfinduced sub-barrier transparency *** describe novel interesting and stimulating analogies between the interaction of nucleus-like solitons on the repulsive barrier and nuclear sub-barrier *** main finding of this study concerns the conservation of total number of nucleons(or the baryon number)in nuclear-like soliton *** show that inelastic interactions among well-dressed repulsive-core solitons arise only when a“cloud”of“dressing”spectral side-bands appears in the frequency spectra of the *** property of nucleus-like solitons is directly related to the nuclear density distribution described by the dimensionless small shape-squareness *** the Fourier spectra of nucleus-like solitons are similar to the nuclear form *** show that the nuclear-like reactions between well-dressed solitons are realized by“exchange”between“particle-like”side bands in their spectra.

关键词： solitons soliton Nonlinear

morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

在线全文

学校读者我要写书评

暂无评论

Journal of mountain Science 2024年第4期21卷 1246-1258页

作者： Dmitrii N.KOZLOv Ekaterina v.LEBEDEvA Institute of marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of Geography Russian Academy of SciencesMoscow 119017Russia

volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric *** has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal *** lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric *** was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were *** observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake Shtyubel has averaged 1-1.6 m per year over the past 25 *** analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their *** results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： volcanic lakes Echolocation survey volcanism Gashydrotherms Kamchatka Kuril Islands

BaTiO3 solid solutions co-doped with Gd3+ and Eu3+:Synthesis,structural evolution and dielectric properties

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第10期42卷 1920-1926页

作者： R.martínez-López m.Pérez-Labra J.A.Romero-Serrano F.R.Barrientos-Hernández m.Reyes-Pérez m.I.valenzuela-Carrillo G.Urbano-Reyes v.E.Reyes-Cruz G.I.Dávila-Pulido Academic Area of Earth Sciences and materials Autonomous University of Hidalgo State metallurgy and materials Department ESIQIE-IPNUPALM Autonomous University of Coahuila Boulevard Adolfo López Mateos S/n

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO3solid solutions codoped with rare earth elements(Gd3+and Eu3+) prepared using the solid-state reaction method are *** pure precursor powders of BaCl3,TiO2,Gd2O3,and Eu2O3were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 mPa and sintered at 1300℃ in air atmosphere for 6 h to obtain Ba1-3xGd2xTi1-3xEu4xO3（x=0,0.0015,0.01 and0.1）.X-ray diffraction（XRD） and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO3for the samples with x=0,0.0015 and 0.01, as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd3+and Eu3+in the BaTiO3structure is reached for the sample with x>0.01,and the orthorhombic Eu2TiO5and monoclinic BaTi2O5secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO3around 716 cm-1（LO of A1 symmetry）,515 cm-1（TO of A1 symmetry）,and 305 cm-1（B1）.The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃ with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the *** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO3 Doping Europium Gadolinium Rare earths Synthesis

Electrostatic Interaction-directed Construction of Hierarchical Nanostructured Carbon Composite with Dual Electrical Conductive Networks for Zinc-ion Hybrid Capacitors with Ultrastability

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Energy & Environmental materials 2024年第1期7卷 184-192页

作者： Changyu Leng Zongbin Zhao Xuzhen Wang Yuliya v.Fedoseeva Lyubov G.Bulusheva Alexander v.Okotrub Jian Xiao Jieshan Qiu State Key Lab of Fine Chemicals School of Chemical EngineeringLiaoning Key Lab for Energy Materials and Chemical Engineering Dalian University of TechnologyDalian 116024China Nikolaev Institute of Inorganic Chemistry Siberian Branch of the Russian Academy of Sciences3 Acad.Lavrentiev Ave.Novosibirsk 630090Russia College of Chemical Engineering Beijing University of Chemical Technology Beijing 100029China

metal-organic framework(mOF)-derived carbon composites have been considered as the promising materials for energy ***,the construction of mOF-based composites with highly controllable mode via the liquid-liquid synthesis method has a great challenge because of the simultaneous heterogeneous nucleation on substrates and the self-nucleation of individual mOF nanocrystals in the liquid ***,we report a bidirectional electrostatic generated self-assembly strategy to achieve the precisely controlled coatings of single-layer nanoscale mOFs on a range of substrates,including carbon nanotubes(CNTs),graphene oxide(GO),mXene,layered double hydroxides(LDHs),mOFs,and SiO_(2).The obtained mOF-based nanostructured carbon composite exhibits the hierarchical porosity(v_(meso)/v_(micro)∶2.4),ultrahigh N content of 12.4 at.%and"dual electrical conductive networks."The assembled aqueous zinc-ion hybrid capacitor(ZIC)with the prepared nanocarbon composite as a cathode shows a high specific capacitance of 236 F g^(-1)at 0.5 A g^(-1),great rate performance of 98 F g^(-1)at 100 A g^(-1),and especially,an ultralong cycling stability up to 230000 cycles with the capacitance retention of 90.1%.This work develops a repeatable and general method for the controlled construction of mOF coatings on various functional substrates and further fabricates carbon composites for ZICs with ultrastability.

关键词： carbon composite electrostatic interaction metal-organic framework coating self-assembly zinc-ion hybrid capacitor

Ambispective epidemiological observational study of varicella-zoster virus infection: An 18 year-single-center Bulgarian experience

在线全文

学校读者我要写书评

暂无评论

World Journal of virology 2024年第3期13卷 82-88页

作者： Hristiana m Batselova Tsvetelina v velikova Department of Epidemiology and Disaster medicine Medical UniversityPlovdivUniversity Hospital“St George”Plovdiv 4000Bulgaria medical Faculty Sofia University St.Kliment OhridskiSofia 1407Bulgaria

BACKGROUND varicella(chickenpox)and herpes zoster(shingles)are outcomes of varicella-zoster virus(vZv)infection,and understanding their incidence trends is vital for public health *** To conduct an ambispective epidemiological study by analyzing the main epidemiological characteristics of vZv infection during an 18 year-period(2000-2018).mETHODS We used descriptive and epidemiological methods to characterize chickenpox in Bulgaria,the city of Plovdiv and the region for a period of 18 years(2000-2018).RESULTS The average incidence of varicella-zoster infection for the period 2000–2018 in the Plovdiv region was estimated at 449.58‰.The highest relative share of the infection was assessed in the month of January at 13.6%,and the lowest in the months of August and September at 2.9%(both months).The age group most affected by the infection was 1-4 years,followed by 5-9 *** corresponds to the so-called"pro-epidemic population"-a phenomenon typical for airborne infections,confirming their mass impact on the perpetuation of vZv *** Our findings reveal significant insights into vZv epidemiology,including age-specific incidence rates,clinical manifestations,and vaccination *** comprehensive analysis contributes to the broader understanding of vZv infec-tion dynamics and may inform evidence-based preventive measures.

关键词： varicella-zoster virus Epidemiology Incidence trends Chickenpox Shingles Public health Pro-epidemic population Age-specific incidence Clinical manifestations vaccination impact