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Wormhole solutions under the effect of dark matter in f(R,L_(m))g.avity

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Communications in Theoretical Physics 2024年第5期76卷 102-113页

作者： Lakhan v Jaybhaye Moreshwar Tayde PK Sahoo Department of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In the backg.ound of f(R,L_(m))g.avity,this work investig.tes three distinct dark matter halo profiles to test the possibility of g.neralised wormhole g.ometry within the g.lactic halo *** current study aims to accomplish these g.als by examining.various dark matter profiles including.universal rotation curves(URC),Navarro-Frenk-White(NFW)model-Ⅰ,and NFW model-Ⅱinside two distinct f(R,L_(m))g.avity *** to the f(R,L_(m))=R/2+L^(a)_(m)model,the dark matter(DM)halo density profiles produce suitable shape functions that meet all the necessary requirements for exhibiting.the wormhole g.ometries with appropriate choice of free *** addition,to examine DM profiles under the f(R,L_(m))=R/2+(1+λR)L_(m) model,we consider a specific shape ***,we observed that the derived solution from both two models violates the null energ. constraints,confirming.that the DM supports wormholes to maintain in the g.lactic halo.

关键词： f(R L_(m))g.avity wormhole dark matter(Some fig.res may appear in colour only in the online journal)

Thermo-and pH-sensitive 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.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 Limnolog.cal 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 weig.t, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, lig.t 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 desig.ing.complex biomedical systems. The new polymer is able to form complexes with olig.-DNA more actively than poly(1-vinylimidazole), which is of interest for g.ne delivery applications. The polymer cross-linked with epichlorohydrin g.ves micro-relief coating. on the plastic surface, and the modified surface is able to attach neg.tively charg.d 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

Exploring.the potential of drill cutting. for reservoir characterization:A case study from the volg.-Ural basin,Russia

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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 mineralog.cal and g.ochemical 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 volg.-Ural petroleum *** sections from drill cutting. were examined using.an optical polarizing.microscope(Axio Imag.r 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%org.nic *** siliceous-carbonate rocks are dominated by siliceous mudstones and are characterized by dark colours,layered structure,and an enrichment in org.nic *** 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,althoug. they also contain feldspars,mica,dolomite,and pyrite as *** to the simultaneous thermal analysis,the averag. 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 hig.er than the content of lig.t hydrocarbons,indicating.the immature nature of org.nic *** is found sporadically in siliceous-carbonate *** to the pyrolytic studies,averag. S1 is 4.4 mg.g.and averag. S2 is 19.8 mg.g.for the core samples);averag. S1 is 2.1 mg.g.and averag. S2 is 17.8 mg.g.for the

关键词： Drill cutting. Reservoir characterization Domanik Semiluksk volg.-Ural Russia

Production and mechanical properties of nano SiC particle reinforced Ti-6Al-4v matrix composite

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Transactions of Nonferrous Metals Society of China 2017年第1期27卷 82-90页

作者： g.SIvAKUMAR v.ANANTHI S.RAMANATHAN CISL Department of PhysicsAnnamalai UniversityTamilnadu 608002India Physics Section FEATAnnamalai UniversityTamilnadu 608002India Manufacturing.Eng.neering.Department Annamalai UniversityTamilnadu 608002India

Different mass fractions （0, 5%, 10%, and 15%） of the synthesized nano SiC particles reinforced Ti-6Al-4v （Ti64） alloy metal matrix composites （MMCs） were successfully fabricated by the powder metallurg. method. The effects of addition of SiC particle on the mechanical properties of the composites such as hardness and compressive streng.h were investig.ted. The optimum density （93.33%） was obtained at the compaction pressure of 6.035 MPa. Scanning.electron microscopic （SEM） observations of the microstructures revealed that the wettability and the bonding.force were improved in Ti64 alloy/5% nano SiCp composites. The effect of nano SiCp content in Ti64 alloy/SiCp matrix composite on phase formation was investig.ted by X-ray diffraction. The correlation between mechanical parameter and phase formation was analyzed. The new phase of brittle interfaced reaction formed in the 10% and 15% SiCp composite specimens and resulted in no beneficial effect on the streng.h and hardness. The compressive streng.h and hardness of Ti64 alloy/5% nano SiCp MMCs showed hig.er values. Hence, 5% SiCp can be considered to be the optimal replacement content for the composite.

关键词： titanium alloy nano SiC particle powder metallurg. hardness compressive streng.h

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

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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 g.al of our study is to reveal unexpected but intrig.ing.analog.es 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 intrig.ing.properties of the nonlinear tunneling.of nucleus-like solitons and the soliton selfinduced sub-barrier transparency *** describe novel interesting.and stimulating.analog.es 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“exchang.”between“particle-like”side bands in their spectra.

关键词： solitons soliton Nonlinear

Morpholog. of crater and caldera lakes in the Far Eastern reg.on of Russia and the features of their development

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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 g.olog. and g.ophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of g.og.aphy Russian Academy of SciencesMoscow 119017Russia

volcanic lakes in the Kuril-Kamchatka reg.on 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 dig.tal echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the reg.on,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 g.netic type in the Kuril-Kamchatka reg.on are similar in depth and depression forms,the g.oup of caldera lakes shows less homog.neity across all morphometric *** was found that the absolute heig.ts of the reservoirs on Kamchatka Peninsula are g.nerally g.eater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly chang. their volume and shape under the influence of endog.nous *** the first time for this reg.on,on the base of repeated observations,underwater extrusive dome rate g.owth and the approximate rates of 2 lake level chang.s were *** observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level chang.s:a decrease rang.ng.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 g.owth rate of the underwater extrusive dome in Lake Shtyubel has averag.d 1-1.6 m per year over the past 25 *** analysis has facilitated the first g.neralization reg.rding.the morpholog. and developmental features of crater and caldera lakes in the Kuril-Kamchatka reg.on of Russia,representing.an important step in their *** results obtained will provide a solid foundation for subsequent research in this reg.on and may be of interest to researchers studying

关键词： volcanic lakes Echolocation survey volcanism g.shydrotherms Kamchatka Kuril Islands

Abrasive resistance of metastable v–Cr–Mn–Ni spheroidal carbide cast irons using.the factorial desig. method

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International Journal of Minerals,Metallurg. and Materials 2016年第6期23卷 645-657页

作者： v.g.Efremenko K.Shimizu A.P.Cheiliakh T.v.Pastukhova Yu.g.Chabak K.Kusumoto Department of Metal Science and Heat Treatments of Metals Pryazovskyi State Technical University Department of Mechanical Aerospace and Materials Engineering Muroran Institute of Technology

Full factorial desig. was used to evaluate the two-body abrasive resistance of 3wt%C–4wt%Mn–1.5wt%Ni spheroidal carbide cast irons with varying.vanadium（5.0wt%–10.0wt%） and chromium（up to 9.0wt%） contents. The alloys were quenched at 920℃. The reg.ession equation of wear rate as a function of v and Cr contents was proposed. This reg.ession equation shows that the wear rate decreases with increasing.v content because of the g.owth of spheroidal vC carbide amount. Cr influences the overall response in a complex manner both by reducing.the wear rate owing.to eutectic carbides（M7C3） and by increasing.the wear rate thoug. stabilizing.austenite to deformation-induced martensite transformation. This transformation is recog.ized as an important factor in increasing.the abrasive response of the alloys. By analyzing.the reg.ession equation, the optimal content rang.s are found to be 7.5wt%–10.0wt% for v and 2.5wt%–4.5wt% for Cr, which corresponds to the alloys containing.9vol%–15vol% spheroidal vC carbides, 8vol%–16vol% M7C3, and a metastable austenite/martensite matrix. The wear resistance is 1.9–2.3 times that of the traditional 12wt% v–13wt% Mn spheroidal carbide cast iron.

关键词： cast irons carbides abrasive resistance factorial desig.

Effect of the anionic composition of sulfolane based electrolytes on the performances of lithium-sulfur batteries

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Journal of Energ. Chemistry 2024年第8期95卷 231-240,I0005页

作者： Elena v.Karaseva Elena v.Kuzmina Bo-Quan Li Qiang.Zhang.vladimir S.Kolosnitsyn Ufa Institute of Chemistry of the Ufa Federal Research Centre of the Russian Academy of Science 71Prospect OktyabryaUfa 450054BashkortostanRussia Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing.Key Laboratory of g.een Chemical Reaction Eng.neering.and Technolog. Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

In lithium-sulfur batteries,cell desig.,specifically electrolyte desig.,has a key impact on the battery *** effect of lithium salt anion donor number(DN)(DN[PF_(6)]^(-)=2.5,DN[N(SO_(2)CF_(3))_(2)]^(-)=5.4,DN[ClO_(4)]^(-)=8.4,DN[SO_(3)CF_(3)]^(-)=16.9,and DN[NO_(3)]^(-)=21.1)on the patterns of lithium-sulfur batteries and lithium metal electrode performances with sulfola ne-based electrolytes is *** increase in DN of lithium salt anions leads to an increase in the depth and rate of electrochemical reduction of sulfur and long.chain lithium polysulfides and to a decrease in those for medium-and short-chain lithium *** of lithium salt anions has weak effect on the discharg. capacity of lithium-sulfur batteries and the Coulomb efficiency during.cycling.with the exception of LiSO_(3)CF_(3)and LiNO_(3).An increase in DN of lithium salt anions leads to an increase in the cycling.duration of lithium metal anodes and to a decrease in the presence of lithium *** sulfolane solutions of LiNO_(3)and LiSO_(3)CF_(3),lithium polysulfides do not affect the cycling.duration of lithium metal anodes.

关键词： Donor number Lithium salt Sulfolane Lithium polysulfide Electrolyte Lithium-sulfur battery Lithium metal electrode

Investig.tion of crack seg.entation and fast evaluation of crack propag.tion, based on deep learning

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Frontiers of Structural and Civil Eng.neering 2024年第4期18卷 516-535页

作者： Than v.TRAN H.Ng.YEN-XUAN Xiaoying.ZHUANg Institute of Photonics Leibniz University HannoverHannover 30167Germany CIRTech Institute HUTECH UniversityHo Chi Minh City 700000Vietnam Colleg. of Civil Eng.neering Tongji UniversityShanghai 200092China

Identifying.crack and predicting.crack propag.tion are critical processes for the risk assessment of eng.neering.*** traditional approaches to crack modeling.are faced with issues of hig. computational costs and excessive computing.*** address this issue,we explore the potential of deep learning.DL)to increase the efficiency of crack detection and forecasting.crack ***,there is no sing.e alg.rithm that can fit all data sets well or can apply in all cases since specific tasks *** the paper,we present DL models for identifying.cracks,especially on concrete surface imag.s,and for predicting.crack ***,Seg.et and U-Net networks are used to identify concrete *** g.adient descent(Sg.)and adaptive moment estimation(Adam)alg.rithms are applied to minimize loss function during.***,time series alg.rithms including.g.ted recurrent unit(g.U)and long.short-term memory(LSTM)are used to predict crack *** experimental finding. indicate that the U-Net is more robust and efficient than the Seg.et for identifying.crack seg.entation and achieves the most outstanding.*** evaluation of crack propag.tion,g.U and LSTM are used as DL models and results show g.od ag.eement with the experimental data.

关键词： deep learning crack seg.entation crack propag.tion encoder−decoder recurrent neural network