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Research in Astronomy and Astrophysics 2024年第7期24卷 135-144页

作者： Ze-Yuan Tang jun-Jie Feng jun-hui Fan School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China

A warm corona has been widely proposed to explain the soft excess(SE)in X-ray above the 2-10 ke V power law extrapolation in Active Galactic Nuclei(AGNs).In actual spectral fittings,the warm coronal seed photon temperature(T_s)is usually assumed to be far away from the soft X-ray,but kT_scan reach close to 0.1 ke V in the standard accretion disk *** this study,we used Monte Carlo simulations to obtain radiation spectra from a slab-like warm corona and fitted the spectra using the spherical-geometry-based routine THCOMP or a thermal *** findings reveal tha high T_scan influence the fitting results.A moderately high kT_s(around 0.03 ke V)can result in an apparent low-temperature and flat SE,while an extremely high kT_s(around 0.07 ke V)can even produce an unobserved blackbody-like *** conclusions indicate that,for spectral fittings of the warm coronal radiation(SE in AGNs),kT_sshould be treated as a free parameter with an upper limit,and an accurate coronal geometry is necessary when kT_s>0.01 ke V.

关键词： galaxies active-accretion-accretion disks-black hole physics

Existence of Positive Solutions to a Fractional-Kirchhoff System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 225-240页

作者： Peng-fei Li jun-hui Xie Dan Mu School of Mathematics and Statistics Hubei Minzu UniversityEnshi445000China

LetΩbe a bounded smooth domain in RN(N≥3).Assuming that 00 are constants,we consider the existence results for positive solutions of a class of fractional elliptic system below,{(a+b[u]^(2)_(s))(-Δ)^(s)u=vp+h_(1)(x,u,v,▽u,▽v),x∈Ω,(-Δ)^(s)v=u^(q)+h_(2)(x,u,▽,▽u,▽v),x∈Q,u,v>0,x∈Ω,u=v=0,x∈RN\Ω.Under some assumptions of hi(x,u,v,▽u,▽v)(i=1,2),we get a priori bounds of the positive solutions to the problem(1.1)by the blow-up methods and rescaling *** on these estimates and degree theory,we establish the existence of positive solutions to problem(1.1).

关键词： fractional-Kirchhoff system a priori bounds degree theory positive solution

Stable stripe and vortex solitons in two-dimensional spin-orbit coupled Bose-Einstein condensates

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Communications in Theoretical Physics 2024年第6期76卷 26-33页

作者： Yuan Guo Muhammad Idrees Ji Lin hui-jun Li Institute of Nonlinear Physics and Department of Physics Zhejiang Normal UniversityJinhua 321004China Zhejiang Institute of Photoelectronics and Zhejiang Institute for Advanced Light Source Zhejiang Normal UniversityJinhua 321004China

We present a flexible manipulation and control of solitons via Bose-Einstein *** the presence of Rashba spin-orbit coupling and repulsive interactions within a harmonic potential,our investigation reveals the numerical local solutions within the *** manipulating the strength of repulsive interactions and adjusting spin-orbit coupling while maintaining a zero-frequency rotation,diverse soliton structures emerge within the *** include plane-wave solitons,two distinct types of stripe solitons,and odd petal solitons with both single and double *** stability of these solitons is intricately dependent on the varying strength of spin-orbit ***,stripe solitons can maintain a stable existence within regions characterized by enhanced spin-orbit coupling while petal solitons are unable to sustain a stable existence under similar *** rotational frequency is introduced to the system,solitons undergo a transition from stripe solitons to a vortex array characterized by a sustained *** rotational directions of clockwise and counterclockwise are non-equivalent owing to spin-orbit *** a result,the properties of vortex solitons exhibit significant variation and are capable of maintaining a stable existence in the presence of repulsive interactions.

关键词： Bose-Einstein condensate spin-orbit coupling rotation frequency stripe solitons vortex array

Radiofrequency ablation combined with transcatheter arterial chemoembolization for recurrent liver cancer

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1756-1764页

作者： Jin-You Guo Li-Li Zhao hui-jun Cai hui Zeng Wei-Dong Mei Department of Oncology The Second People's Hospital of Zhejiang Province Taizhou Yuhuan CityTaizhou 317605Zhejiang ProvinceChina Department of Interventional China's Zhejiang Province Tumor HospitalHangzhou 310000Zhejiang ProvinceChina

BACKGROUND The recurrence rate of liver cancer after surgery is *** ablation(RFA)combined with transcatheter arterial chemoembolization(TACE)is an effective treatment for liver cancer;however,its efficacy in recurrent liver cancer remains *** To investigate the clinical effect of TACE combined with RFA in the treatment of recurrent liver *** Ninety patients with recurrent liver cancer were divided into 2 groups according to treatment plan:Control(RFA alone);and experimental[TACE combined with RFA(TACE+RFA)].The incidence of increased alanine aminotransferase levels,complications,and other indices were compared between the two groups before and after the *** One month after the procedures,the short-term efficacy rate and Karnofsky Performance Status scores of the experimental group were significantly higher than those of the control group(P0.05).CONCLUSION TACE+RFA was effective for the treatment of recurrent liver cancer and significantly reduced AFP levels and improved various indices of liver function.

关键词： Transcatheter arterial chemoembolization Radiofrequency ablation Recurrent liver cancer Clinical efficacy Overall response rate Disease control rate

Microstructure and texture evolution of Cu–Cr–Co–Ti alloys during the two-stage cryorolling

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Rare Metals 2024年第9期43卷 4535-4547页

作者： Jia-jun Zhang Long-Jian Li Zhi-Feng Liu Zong-Ning Chen En-Yu Guo hui-jun Kang Ren-Geng Li Tong-Min Wang Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province) School of Materials Science and EngineeringDalian University of Technology Center of Hyper-Gravity Experimental and Interdisciplinary Research Zhejiang University Ningbo Institute of Dalian University of Technology！Ningbo315000 China Key Laboratory for Light-Weight Materials Nanjing Tech University

This study entailed an investigation of the mechanical properties, microstructural and texture orientation evolutions of CuDCrDCoDTi alloys prepared via twostage cryorolling and intermediate aging treatment. To this end, X-ray diffraction and electron backscatter diffraction were employed. The results indicate that the two-stage cryorolling and intermediate aging treatments led to the development of profuse twin bundles and significantly enhanced the mechanical properties. The initial cryorolling led to coplanar slip and developed a strong Y({111} ) orientation, accelerating the formation of Goss({011} ) orientation and a Brass-type *** intermediate aging treatment relieved the restriction on dislocation slip and reoriented the grains toward the Copper({112} ) and Z({111} ) *** Z orientation, with a relatively high volume fraction,dominated the macrotexture. Secondary cryorolling intensified twinning and shear banding, transforming the Copper-type shear bands into Brass-type shear bands with rhomboidal prism morphology. The areas inside the Brasstype shear bands exhibited a Y orientation, and the areas outside the shear bands exhibited a stable Brass-type texture. The evident decrease in the weighted Schmid factors demonstrated that the two-stage cryorolling and intermediate aging treatment can modify the texture evolution and aid the design of high-performance Cu alloys.

关键词： Copper alloys Electron backscatter diffraction Macrotexture evolution Schmid factor Two-stage cryorolling

A comparative lattice analysis of SU(2)dark glueballs

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Chinese Physics C 2024年第8期48卷 113-126页

作者： Min-Huan Chu jun-hui Lai Wei Wang Jialu Zhang Qianteng Zhu INPAC Key Laboratory for Particle Astrophysics and Cosmology(MOE)Shanghai Key Laboratory for Particle Physics and CosmologySchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Yang Yuanqing Scientific Computering Center Tsung-Dao Lee InstituteShanghai Jiao Tong UniversityShanghai 200240China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

We study the mass and scattering cross section of SU(2)glueballs as dark matter candidates using lattice *** employ both naive and improved SU(2)gauge actions in 3+1 dimensions with severalβvalues,and we adopt both the traditional Monte Carlo method and flow-based model based on machine learning techniques to generate lattice *** mass of a dark scalar glueball with J^(PC)=0^(++)and the Nambu-Bethe-Salpeter wave function are *** a coupling constant ofβ=2.2 as an illustration,we compare the dark glueball mass calculated from the configurations generated from the two *** consistent results can be achieved,the two methods demonstrate distinct *** the Runge-Kutta method,we extract the glueball interaction potential and two-body scattering cross *** the observational constraints,we obtain the lower bound of the mass of scalar glueballs as candidates of dark matter.

关键词： lattice QCD dark matter machine learning

Structural engineering of hard carbon through spark plasma sintering for enhanced sodium-ion storage

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Rare Metals 2024年第9期43卷 4274-4285页

作者： Hao-Ming Xiao Heng Zheng Ping Yuan jun-hui Luo Lin-Lin Shen Jie-Feng Tan Xian-You Luo De Li Yong Chen Guangdong Key Laboratory for Hydrogen Energy Technologies School of Materials Science and Hydrogen EnergyFoshan University State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti ResourcesHainan University

Hard carbon （HC） has emerged as one of the superior anode materials for sodium-ion batteries （SIBs）,with its electrochemical performance significantly influenced by the presence of oxygen functional groups and its closed pore ***,current research on the structural adjustment of these oxygen functional groups and the closed pore architecture within HC remains ***,energy-efficient and contamination-free spark plasma sintering technology was employed to tune the structure of coconut-shell HC,resulting in significant adjustments to the content of carboxyl （decreasing from 5.71 at%to 2.12 at%） and hydroxyl groups （decreasing from 7.73 at % to 6.26 at%）.Crucially,these modifications reduced the irreversible reaction of oxygen functional groups with Na+.Simultaneously,a substantial number of closed pores with an average diameter of 1.22 nm were generated within the HC,offering an ideal environment for efficient Na+*** structural changes resulted in a remarkable improvement in the electrochemical performance of the modified *** reversible specific capacity of the modified HC surged from 73.89 mAh·g-1to an impressive 251.97 m Ah·g-1at a current density of 50 mA·*** at 400 mA·g-1,the reversible specific capacity increased significantly from 14.55 to 85.44 mAh·***,this study provides a novel perspective for designing tailored HC materials with the potential to develop high-performance SIBs.

关键词： Closed pores Hard carbon Oxygen functional groups Sodium-ion batteries Spark plasma sintering

The Optical Variability Properties of TeV Blazars

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Research in Astronomy and Astrophysics 2024年第9期24卷 68-77页

作者： Zi-An Su Wen-Xin Yang Xiang-Tao Zeng Le-Jian Ou Ze-Lin Li Jiang-He Yang jun-hui Fan Department of Physics School of Physics and Electronics Hunan Normal University Center for Astrophysics Guangzhou University Greater Bay Brand Center of the National Astronomical Data Center Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province College of Microelectronics Feicuihu Campus of Hefei University of Technology College of Mathematics and Physics Science Hunan University of Arts and Science

Variability is one of the typical observational properties of blazars and the spectral changes are usually associated with variability,although this kind of association is unclear *** this work,we used data from the Steward Observatory blazar monitoring program to investigate the optical variability properties including the short-term timescale,the brightness-dependent spectral property,the correlation between the the brightness variation and the polarization,and then estimate the Doppler factors based on the obtained short timescale to study the polarization property for a sample of 20 TeV *** analyses arrive at the following results:（1） The largest variation amplitude in R-band,ΔRM,covers a range fromΔRM=0.29 mag （1ES 2344+514） toΔRM=4.66 mag （3C 279）.（2） Intra-day variability was found from five sources with timescales from 0.14 day for S5 0716+714 to 0.98 day for PKS 2155–*** sources show spectra that are bluer when they become brighter,suggesting a common bluer-when-brighter property.（3） The plot of the polarization versus estimated Doppler factor is consistent with the Doppler factor dependent formula of polarization.（4） The largest polarization is correlated with the largest optical variation,suggesting that the high polarization and high amplitude variation are both the indicator of beaming effect.

关键词： galaxies: active galaxies: jets radiation mechanisms: non-thermal

Probing the Gamma-Ray Emission Region of Five TeV Flat Spectrum Radio Quasars

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Research in Astronomy and Astrophysics 2024年第6期24卷 156-169页

作者： Hu-Bing Xiao Hai-Tao Cao Rui Xue Jin-Ting Cai Ge-Ge Wang Marina Manganaro Shao-Hua Zhang Zhi-Hao Ouyang Li-Ping Fu jun-hui Fan Shanghai Key Lab for Astrophysics Shanghai Normal UniversityShanghai 200234China School of Information Engineering Guangzhou Panyu PolytechnicGuangzhou 511483China Department of Physics Zhejiang Normal UniversityJinhua 321004China College of Mathematics and Physics Guangxi Minzu UniversityNanning 530006China Key Laboratory of Cosmology and Astrophysics(Liaoning) College of SciencesNortheastern UniversityShenyang 110819China Department of Physics University of RijekaRijeka 51000Croatia Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China

The location ofγ-ray emission of blazars remains a contested topic,inspiring the development of numerous investigative techniques to address this *** this work,we analyzed Fermiγ-ray light curves in the GeV and MeV bands,employing the discrete cross-correlation function method to discern time lags between the two *** 4C+21.35,Ton 599,B21420+32,and PKS 1510-089,we identified a time lag spanning several days,while for PKS 1441+25,the time lag was not statistically *** results imply that the soft photons necessary for inverse Compton scattering predominantly originate from the dusty torus in the first four sources,whereas for PKS1441+25,they seem to be sourced mainly from the broad-line *** analysis of the opacity(τγγ)and the GeV spectra study supports the conclusion that the location of the dissipation region must be beyond the BLR to avoid significant ***,for PKS 1441+25,the emission region is also posited to lie outside yet proximate to the *** parameters of describing the emission region were obtained by fitting broadband spectral energy distribution with contemporaneous observation *** findings suggest that for the five TeV FSRQs,during Te V flaring events,the jet appears to maintain an equilibrium between the energy density of the magnetic field and that of the particles for all investigated sources,with the exceptions of 4C+21.35 and PKS1441+*** terms of the overall jet power,particle energy is the dominant contributor,and the observed blazar radiation cannot be solely attributed to the magnetic field,except in the case of 4C+***,magnetic reconnection is unlikely to be the primary mechanism behind particle acceleration in these systems.

关键词： galaxies:active gamma-rays:galaxies galaxies:jets

Elucidating ligand effects in rhodium(Ⅲ)-catalyzed arene-alkene coupling reactions

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Chinese Chemical Letters 2024年第5期35卷 130-134页

作者： Kongchuan Wu Dandan Lu Jianbin Lin Ting-Bin Wen Wei Hao Kai Tan hui-jun Zhang Department of Chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China

Rhodium(Ⅲ)-catalyzed C-H couplings of arenes with alkenes are among the most powerful methods for C-C bond *** these transformations,subtle manipulation of ancillary ligands can lead to dramatic changes in reactivity and ***,detailed mechanistic studies concerning the ligand effects are *** this study,we investigated the origin of ligand-controlled product-selectivity in rhodium(Ⅲ)-catalyzed C-H couplings of arenes with alkenes,using a series of well-defined[CpXRhⅢ]complexes that feature electronically or sterically distinct Cp^(X)(Cp(η^(5)-C_(5)H_(5)),Cp^(CF3)(η^(5)-C_(5)Me_(4)CF_(3))and Cp^(∗)(η^(5)-C_(5)Me_(5)))ligands.A combination of experimental and theoretical investigations showed that(i)rhodium hydride species containing the electron rich Cp^(∗)ligand can undergo reinsertion of the alkene,thereby allowing rhodium-walking,(ii)rhodium hydride species involving the electron-deficient Cp or Cp^(CF3) ligands prefer reductive elimination rather than alkene *** findings offer valuable insights on future rational catalyst design for selective arene-alkene cross coupling reactions.

关键词： Organometallics Transition metal catalysis Arene-alkene coupling β-H elimination Rhodium hydride