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probing the Bardeen-Kiselev black hole with the cosmological constant caused by Einstein equations coupled with nonlinear electrodynamics using quasinormal modes and greybody bounds

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Communications in Theoretical physics 2024年第6期76卷 102-119页

作者： S r Wu B Q Wang z W Long College of physics Guizhou UniversityGuiyang 550025China College pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this work,we investigate a static and spherically symmetric Bardeen-Kiselev black hole(BH)with the cosmological constant,which is a solution of the Einstein-non-linear Maxwell field *** compute the quasinormal frequencies for the Bardeen-Kiselev BH with the cosmological constant due to electromagnetic and gravitational *** varying the BH parameters,we discuss the behavior of both real and imaginary parts of the BH quasinormal frequencies and compare these frequencies with the reissner-Nordström-de Sitter BH surrounded by quintessence(rN-dSQ).Interestingly,it is shown that the responses of the Bardeen-Kiselev BH with the cosmological constant and the rN-dSQ under electromagnetic perturbations are different when the charge parameter q,the state parameter w and the normalization factor c are varied;however,for the gravitational perturbations,the responses of the Bardeen-Kiselev BH with the cosmological constant and the rN-dSQ are different only when the charge parameter q is ***,compared with the gravitational perturbations,the electromagnetic perturbations can be used to understand nonlinear and linear electromagnetic fields in curved spacetime *** interesting observation is that,due to the presence of Kiselev quintessence,the electromagnetic perturbations around the Bardeen-Kiselev BH with the cosmological constant damps faster and oscillates slowly;for the gravitational perturbations,the quasinormal mode decays slowly and oscillates *** also study the reflection and transmission coefficients along with the absorption cross section in the Bardeen-Kiselev BH with the cosmological constant;it is shown that the transmission coefficients will increase due to the presence of Kiselev quintessence.

关键词： quasinormal modes greybody factors Bardeen-Kiselev black hole with cosmological constant

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Flat Band and η-pairing States in a One-Dimensional MoiréHubbard Model

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Chinese physics Letters 2024年第4期41卷 69-76页

作者：王冉宋智 College of physics and Materials Science Tianjin Normal UniversityTianjin 300387China School of physics Nankai UniversityTianjin 300071China

A Moirésystem is formed when two periodic structures have a slightly mismatched period,resulting in unusual strongly correlated states in the presence of particle-particle *** periodic structures can arise from the intrinsic crystalline order and periodic external *** investigate a one-dimensional Hubbard model with periodic on-site potential of period n_(0),which is commensurate to the lattice *** large n_(0),the exact solution demonstrates that there is a midgap flat band with zero energy in the absence of Hubbard *** Moiréunit cell contributes two zero energy levels to the flat *** the presence of Hubbard interaction,the midgap physics is demonstrated to be well described by a uniform Hubbard chain in which the effective hopping and on-site interaction strength can be controlled by the amplitude and period of the external *** simulations are performed to demonstrate the correlated behaviors in the finite-sized Moiré Hubbard system,including the existence of an η-pairing state and bound pair *** finding provides a method to enhance the correlated effect by a spatially periodic external field.

关键词： oscillation interaction field

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Investigation of Microstructure, Microhardness and Thermal properties of Ag-In Intermetallic Alloys prepared by Vacuum Arc Meltings

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 182-187页

作者： ÇELİK Erçevik ATA ESENEr pınar ÖzTÜrK Esra AKSÖz Sezen Nevşehir HacıBektaşVeli University Department of Physics50300NevşehirTurkey Erciyes University Graduate School of Natural and Applied Sciences38039KayseriTurkey Kocaeli University Department of Physics41380KocaeliTurkey

Ag-In intermetallic alloys were produced by using vacuum arc furnace. Differential Scanning Calorimetry(DSC) and Energy Dispersive X-ray Spectrometry(EDX) were used to determine the thermal properties and chemical composition of the phases respectively. Microhardness values of Ag-In intermetallics were calculated with Vickers hardness measurement method. According to the experimental results, Ag-34 wt%In intermetallic system generated the best results of energy saving and storage compared to other intermetallic systems. Also from the microhardness results, it was observed that intermetallic alloys were harder than pure silver and Ag-26 wt%In system had the highest microhardness value with 143.45 kg/mm^(2).

关键词： thermal properties microstructure character.zation microhardness alloys material character.zation

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rational design of AgGaS/znS/znS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu z.z.Fu Y.Y.Chen H.Q.Dai z.Hu W.L.zhang r.Q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu research Institute of Fudan University YiwuZhejiang 322000China zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/znS/znS quantum dots(QDs).In the first step,an inner.znS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer.znS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/znS/znS QDs showed an excellent photoluminescence quantum yield(pLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest pLQY reported thus far for AgGaS ***,the effect of halogen ions in zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between zn cation diffusion and znS shelling ***,the znS shelling reaction was dominant when znCl_(2)was employed,while zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the znS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots photoluminescence Core/shell Alloyed core/shell interface

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Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.L.zhu S.M.Weng p.Li X.F.Li H.Ai H.r.pan z.M.Sheng Key Laboratory for Laser plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China research Center of Laser Fusion of China Academy of Engineering physics MianyangSichuan 621900China State key Laboratory of High Field Laser physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-Ir)to teraher.z(THz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-Ir or THz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-Ir or THz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength Ir and THz spectral ranges.

关键词： laser ultrashort photon

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prediction of the undrained shear strength of remolded soil with non-linear regression,fuzzy logic,and artificial neural network

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Journal of Mountain Science 2024年第9期21卷 3108-3122页

作者： YÜNKÜL Kaan KArAÇOr Fatih GÜrBÜz Ayhan BUDAK TahsinÖmür Department of Civil Engineering Faculty of Engineering and ArchitectureTokat Gaziosmanpaşa UniversityTokat 60100Türkiye Department of Civil Engineering Faculty of Engineering and ArchitectureKafkas UniversityKars 36000Türkiye Department of Civil Engineering Faculty of EngineeringGazi UniversityAnkara 06570Türkiye Ministry of Youth and Sports Ankara 06090Türkiye

This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results from 230 different remolded soil test settings reported in 21 publications were collected,utilizing six different measurement *** water content,plastic limit,and liquid limit were used as input parameters for fuzzy logic and artificial neural network modeling,liquidity index or water content ratio was considered as an input parameter for non-linear regression *** non-linear regression analyses,12 different regression equations were derived for the prediction of undrained shear strength of remolded ***-Forward backpropagation and the TANSIG transfer function were used for artificial neural network modeling,while the Mamdani inference system was preferred with trapezoidal and triangular membership functions for fuzzy logic *** experimental results of 914 tests were used for training of the artificial neural network models,196 for validation and 196 for *** was observed that the accuracy of the artificial neural network and fuzzy logic modeling was higher than that of the non-linear regression ***,a simple and reliable regression equation was proposed for assessments of undrained shear strength values with higher coefficients of determination.

关键词： Undrained shear strength Liquidity index Water content ratio Non-linear regression Artificial neural networks Fuzzy logic

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Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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Journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang z.Yang S.Y.Yang z.H.Dai Y.J.Liu J.H.Liao G.Y.zhong z.J.Xie Y.p.Fang S.S.zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure photothermal effect photocatalyst Hydrogen evolution

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precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou L.F.zhang H.Q.Ye z.Q.Yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys rapid solidification Scanning-transmission electron microscopy.

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COVID-19 vaccination produces exercise-responsive SArS-CoV-2 specific T-cells regardless of infection history

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Journal of Sport and Health Science 2024年第1期13卷 99-107页

作者： Kyle A.Smith Tiffany M.zúñiga Forrest L.Baker Helena Batatinha Charles r.pedlar Shane C.Burgess Michael p.Gustafson Emmanuel Katsanis richard J.Simpson School of Nutritional Sciences and Wellness The University of ArizonaTucsonAZ 85721USA Department of pediatrics The University of ArizonaTucsonAZ 85724USA Faculty of Sport Allied Health and Performance ScienceSt.Mary's UniversityTwickenham TW14SXUK Institute of Sport Exercise and Health University College LondonLondon WC1E 7HUUK Department of Animal and Comparative Biomedical Sciences The University of ArizonaTucsonAZ 85721USA The University of Ar.zona Cancer Center The University of ArizonaTucsonAZ 85719USA Laboratory Medicine and pathology Mayo Clinic ArizonaPhoenixAZ 85054USA Department of Immunobiology The University of ArizonaTucsonAZ 85724USA Department of Medicine The University of ArizonaTucsonAZ 85724USA Department of pathology The University of ArizonaTucsonAZ 85724USA

Background:The mobilization and redistribution of severe acute respiratory syndrome coronavirus 2(SArS-CoV-2)specific T-cells and neutralizing antibodies(nAbs)during exercise is purported to increase immune surveillance and protect against severe coronavirus disease 2019(COVID-19).We sought to determine if COVID-19 vaccination would elicit exercise-responsive SArS-CoV-2 T-cells and transiently alter nAb ***:Eighteen healthy participants completed a 20-min bout of graded cycling exercise before and/or after receiving a COVID-19 *** major leukocyte subtypes were enumerated before,during,and after exercise by flow cytometry,and immune responses to SArS-CoV-2 were determined using whole blood peptide stimulation assays,T-cell receptor(TCr)-βsequencing,and SArS-CoV-2 nAb ***:COVID-19 vaccination had no effect on the mobilization or egress of major leukocyte subsets in response to intensity-controlled graded ***,non-infected participants had a significantly reduced mobilization of CD4+and CD8+naive T-cells,as well as CD4+central memory T-cells,after vaccination(synthetic immunity group);this was not seen after vaccination in those with prior SArS-CoV-2 infection(hybrid immunity group).Acute exercise after vaccination robustly mobilized SArS-CoV-2 specific T-cells to blood in an intensity-dependent *** groups mobilized T-cells that reacted to spike protein;however,only the hybrid immunity group mobilized T-cells that reacted to membrane and nucleocapsid *** increased significantly during exercise only in the hybrid immunity ***:These data indicate that acute exercise mobilizes SArS-CoV-2 specific T-cells that recognize spike protein and increases the redistribution of nAbs in individuals with hybrid immunity.

关键词： Anti-viral COVID-19 Exercise immunology SArS-CoV-2 T-Cells Vaccine

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risk factors for hepatocellular carcinoma associated with hepatitis C genotype 3 infection:A systematic review

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1596-1612页

作者： Hamzah z Farooq Michael James Jane Abbott patrick Oyibo pip Divall Naheed Choudhry Graham r Foster Blizard Institute Queen Mary University of LondonLondon E12ATUnited Kingdom School of Health and psychological Sciences University of LondonLondon EC1V 0HBUnited Kingdom University Hospitals of Leicester Library University Hospitals of Leicester NHS TrustLeicester LE39QPUnited Kingdom

BACKGrOUND Hepatitis C virus(HCV)is a blood-borne virus which globally affects around 79 million people and is associated with high morbidity and *** infection leads to cirrhosis in a large proportion of patients and often causes hepatocellular carcinoma(HCC)in people with *** the 6 HCV genotypes(G1-G6),genotype-3 accounts for 17.9%of *** genotype-3 responds least well to directly-acting antivirals and patients with genotype-3 infection are at increased risk of HCC even if they do not have *** To systematically review and critically appraise all risk factors for HCC secondary to HCV-G3 in all ***,we studied possible risk factors for HCC due to HCV-G3 in the literature from 1946 to *** This systematic review aimed to synthesise existing and published studies of risk factors for HCC secondary to HCV genotype-3 and evaluate their strengths and *** searched Web of Science,Medline,EMBASE,and CENTrAL for publications reporting risk factors for HCC due to HCV genotype-3 in all settings,*** Four thousand one hundred and forty-four records were identified from the four databases with 260 records removed as *** thousand eight hundred and eighty-four records were screened with 3514 *** hundred and seventy-one full-texts were assessed for eligibility with seven studies included for *** the seven studies,three studies were retrospective case-control trials,two retrospective cohort studies,one a prospective cohort study and one a cross-sectional study *** were based in hospital settings with four in pakistan,two in South Korea and one in the United *** total number of participants were 9621 of which 167 developed HCC(1.7%).All seven studies found cirrhosis to be a risk factor for HCC secondary to HCV genotype-3 followed by higher age(five-studies),with two studies each showing male sex,high alpha feto-protein,directly-acting antivirals trea

关键词： Hepatocellular carcinoma Hepatitis C Genotype 3 Systematic review Blood-borne viruses Liver cancer

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