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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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Structural regulation of coal-derived hard carbon anode for sodium-ion batteries via pre-oxidation

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Rare Metals 2024年第6期43卷 2585-2596页

作者： Meng-Yuan Su Kai-Yang z.ang Edison Huixiang ang Xue-Li z.ang Yan-Ning Liu Jia-Lin Yang zhen-Yi Gu Faaz A.Butt Xing-long Wu Faculty of Chemistry Northeast Normal UniversityChangchun 130024China MOE Key Laboratory for UV Light-Emiting Materials and Technology.Northeast Normal University.Ministry of Education Changchun 130024China Natural Sciences and Science Education National Institute of EducationNanyang Technological UniversitySingapore 637616Singapore Materials Engineering Department NED University of Engineering and TechnologyKarachi 75300Pakistan

Hard carbon(HC)is broadly recognized as an exceptionally prospective candidate for the anodes of sodium-ion batteries(SIBs),but their practical implementation faces substantial limitations linked to precursor factors,such as reduced carbon yield and increased ***,a cost-effective approach is proposed to prepare a coal-derived HC anode with simple pre-oxidation followed by a post-carbonization process which effectively expands the d_(002)layer spacing,generates closed pores and increases defect *** these modifications,the resulting HC anode attains a delicate equilibrium between plateau capacity and sloping capacity,showcasing a remarkable reversible capacity of 306.3 mAh·g^(-1)at 0.03 A·g^(-1).Furthermore,the produ ced HC exhibits fast reaction kinetics and exceptional rate performance,achieving a capacity of 289 mAh·g^(-1)at 0.1 A·g^(-1),equivalent to~94.5%of that at 0.03 A·g^(-1).When implemented in a full cell configuration,the impressive electrochemical performance is evident,with a notable energy density of 410.6 Wh·kg^(-1)(based on cathode mass).In short,we provide a straightforward yet efficient method for regulating coal-derived HC,which is crucial for the widespread use of SIBs anodes.

关键词： Sodium-ion batteries Hard carbon Anode Coal Pre-oxidation

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IMTNet: Improved Multi-Task Copy-Move Forgery Detection Network with Feature Decoupling and Multi-Feature Pyramid

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Computers, Materials and Continua 2024年第3期80卷 4603-4620页

作者： Wang H. Jiang z. Qian Q. long Y. School of Information Guizhou University of Finance and Economics Guiyang 550025 China College of Big Data Statistics Guizhou University of Finance and Economics Guiyang 550025 China

Copy-Move Forgery Detection (CMFD) is a technique that is designed to identify image tampering and locate suspicious areas. However, the practicality of the CMFD is impeded by the scarcity of datasets, inadequate quality and quantity, and a narrow range of applicable tasks. These limitations significantly restrict the capacity and applicability of CMFD. To overcome the limitations of existing methods, a novel solution called IMTNet is proposed for CMFD by employing a feature decoupling approach. Firstly, this study formulates the objective task and network relationship as an optimization problem using transfer learning. Furthermore, it thoroughly discusses and analyzes the relationship between CMFD and deep network architecture by employing ResNet-50 during the optimization solving phase. Secondly, a quantitative comparison between fine-tuning and feature decoupling is conducted to evaluate the degree of similarity between the image classification and CMFD domains by the enhanced ResNet-50. Finally, suspicious regions are localized using a feature pyramid network with bottom-up path augmentation. Experimental results demonstrate that IMTNet achieves faster convergence, shorter training times, and favorable generalization performance compared to existing methods. Moreover, it is shown that IMTNet significantly outperforms fine-tuning based approaches in terms of accuracy and F1 Copyright © 2024 The Authors. Published by Tech Science Press.

关键词： feature decoupling Image copy-move detection multi-scale feature pyramids passive forensics

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Size matters:the biochemical logic of ligand type in endocrine crosstalk

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Life Metabolism 2024年第1期3卷 10-20页

作者： Jameel Barkat Lone Jonathan z.long Katrin J.Svensson Department of Pathology Stanford University School of MedicineStanfordCA 94305United States Department of Chemistry Stanford UniversityStanfordCA 94305United States Stanford Diabetes Research Center Stanford University School of MedicineStanfordCA 94305United States Sarafan ChEM-H Stanford UniversityStanfordCA 94305United States Wu Tsai Human Performance Alliance Stanford UniversityStanfordCA 94305United States Stanford Cardiovascular Institute Stanford University School of MedicineCA 94305United States

The endocrine system is a fundamental type of long-range cell-cell communication that is important for maintaining metabolism,physiology,and other aspects of organismal *** signaling is mediated by diverse blood-borne ligands,also called hormones,including metabolites,lipids,steroids,peptides,and *** size and structure of these hormones are fine-tuned to make them bioactive,responsive,and adaptable to meet the demands of changing *** has nature selected such diverse ligand types to mediate communication in the endocrine system?What is the chemical,signaling,or physiologic logic of these ligands?What fundamental principles from our knowledge of endocrine communication can be applied as we continue as a field to uncover additional new circulating molecules that are claimed to mediate long-range cell and tissue crosstalk?This review provides a framework based on the biochemical logic behind this crosstalk with respect to their chemistry,temporal regulation in physiology,specificity,signaling actions,and evolutionary development.

关键词： endocrine ligand size metabolites signaling evolution

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Recent progress in single crystal perovskite X-ray detectors

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Science China(Information Sciences) 2024年第3期67卷 5-19页

作者： Xiao LIU Jun REN Yu-ang CHEN Xiangshun GENG Dan XIE Tian-Ling REN School of Integrated Circuits Tsinghua University Beijing National Research Center for Information Science and Technology (BNRist)

Perovskites have attracted extensive attention as radiation detection material due to their long carrier diffusion length and lifetime, high absorption coefficient, and flexible manufacturing process. Compared with polycrystalline structures, single crystal perovskites improve the performance of optoelectronic devices due to their low defect state density, better photoelectric characteristics, and chemical ***, we review the recent progress of single crystal perovskite X-ray detectors. First, we briefly introduced the basic concepts, detection mechanisms, figure of merits of perovskite X-ray detectors, and the preparation methods of single crystal perovskites. Then, we summarized the significant advancements in single crystal perovskite X-ray detectors in recent times. Finally, we discussed the critical challenges and some practicable solutions for developing high-performance X-ray detectors.

关键词： single crystal perovskites carrier transport radiation detection X-ray detectors X-ray imaging

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Spatiotemporal variations of parameters of internal solitary waves in the northern South China Sea

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Journal of Oceanology and Limnology 2024年第2期42卷 421-438页

作者： Yu’ang LIU Yifei JIang Xiaojiang z.ang zhiyuan Wang Yu CAO Huizan Wang College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China

The dynamic parameters for internal solitary waves(ISWs)derived from the extended Korteweg-de Vries(eKdV)equation play an important role in the understanding and prediction of *** spatiotemporal variations of the dynamic parameters of the ISWs in the northern South China Sea(SCS)were studied based on the reanalysis of long-term temperature and salinity *** results for spectrum analysis show that there are definite geographical differences for the periodic variation of the parameters:in shallow water,all parameters vary with a wave period of one year,while in deep water wave components of the parameters at other frequencies *** wavelet analysis,the wavelet power spectral densities in deep water exhibited an inter-annual variation *** example,the wave component of the dispersion coefficient with a wave period of about half a year reached its power peak once every two *** on previous work,this inter-annual variation pattern was deduced to be caused by dynamic *** further work on the regulatory mechanisms,empirical orthogonal function(EOF)decomposition was *** was found that the modes of the dispersion coefficient have different geographical distributions,explaining the reason why the wave components in different frequencies appeared in different *** numerical simulation results confirm that the variations in the parameters of the ISWs derived from the eKdV equation could affect the waveforms significantly because of changes in the polarity of the ***,the periodic variations of the dynamic parameters are related to the geographical location because of dynamic processes operating.

关键词： internal solitary waves(ISWs) dynamic parameters eKdV equation spatiotemporal variation polarity empirical orthogonal function(EOF)decomposition

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Interface catalytic reduction of alumina by nickle for the aluminum nanowire growth: Dynamics observed by in situ TEM

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Nano Research 2024年第3期17卷 1225-1231页

作者： zichun Wang Dan Wang ang Li Lizhuo Wang Xiaodong Han Yijiao Jiang Jianfeng Chen Jun Huang Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic–Inorganic CompositesBeijing University of Chemical TechnologyBeijing 100029China Laboratory for Catalysis Engineering School of Chemical and Biomolecular EngineeringThe University of SydneyNew South Wales 2006Australia Beijing Key Laboratory of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing 100024China Department of Engineering Macquarie UniversitySydneyNew South Wales 2109Australia

Metal nanowires show promise in a broad range of applications and can be fabricated via a number of methods,such as vapor–liquid–solid process and template-based ***,the synthesis of Al nanowires(NWs)is still challenging from the stable alumina *** this work,the Ni-catalyzed fabrication of Al NWs has been realized using various Al_(2)O_(3) *** growth dynamics of Al NWs on Ni/Al_(2)O_(3) was studied using in situ transmission electron microscopy(TEM).The effect of alumina structures,compositions,and growth temperature were *** growth of Al NWs correlates with the Na addition to the alumina *** no eutectic mixture of nickel aluminide was formed,a mechanism of Ni-catalyzed reduction of Al_(2)O_(3) for Al NWs growth has been proposed instead of the vapor–liquid–solid *** key insights reported here are not restricted to Ni-catalyzed Al NWs growth but can be extended to understanding the dynamic change and catalytic performance of Ni/Al_(2)O_(3) under working conditions.

关键词： in situ transmission electron microscopy(TEM) Al nanowires alumina reduction nanowire growth

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X-ray excited Mn^(2+)-doped persistent luminescence materials with biological window emission for in vivo bioimaging

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Journal of Rare Earths 2024年第1期42卷 28-35,I0001页

作者： Hanrun zheng Lin Liu Yi’ang Li Rui Rong Liang Song Junpeng Shi Jing Teng Xia Sun Yun z.ang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China University of the Chinese Academy of Sciences Beijing100049China Xiamen Hospital of Traditional Chinese Medicine Xiamen361015China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China

In recent years,persistent luminescence materials(PLMs)excited by X-rays and emitting in biological windows have received extensive attention in the field of high-sensitivity *** metal Mn^(2+)is an ideal emission center,but few studies focus on Mn^(2+)-doped PLMs with X-ray excitation and biological window ***,we report a Mn^(2+)-doped PLM,LiYGeO_(4):Mn^(2+)(LYGM),with excellent biological window persistent luminescence *** excitation by UV,LYGM produces a durable biological window of persistent luminescence emission at 660 nm for up to 20 *** *** can be repeatedly excited by X-rays,resulting in long-term biological window persistent luminescence *** addition,we obtain LYGM around 200 nm in diameter by ball milling and centrifugation and improve its biocompatibility by surface modification to apply it to in vivo imaging in *** LYGM are injected into mice through the tail vein,in situ excitation of X-rays can be *** the persistent luminescence decays,LYGM can be re-excited for repeated ***,LYGM shows potential prospects for in vivo deep tissue and long-term bioimaging.

关键词： Persistent luminescence X-ray Biological window In vivo imaging Rare earths

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Design Strategies for Aqueous zinc Metal Batteries with High zinc Utilization: From Metal Anodes to Anode-Free Structures

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Nano-Micro Letters 2024年第4期16卷 305-349页

作者： Xianfu z.ang long z.ang Xinyuan Jia Wen Song Yongchang Liu School of Materials Science and Engineering University of Science and Technology Beijing30 College RoadBeijing 100083People’s Republic of China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyState Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China

Aqueous zinc metal batteries(AzMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low redox potential of zinc(zn) metal. However,several issues such as dendrite formation, hydrogen evolution, corrosion, and passivation of zn metal anodes cause irreversible loss of the active materials. To solve these issues, researchers often use large amounts of excess zn to ensure a continuous supply of active materials for zn anodes. This leads to the ultralow utilization of zn anodes and squanders the high energy density of AzMBs. Herein, the design strategies for AzMBs with high zn utilization are discussed in depth, from utilizing thinner zn foils to constructing anode-free structures with theoretical zn utilization of 100%, which provides comprehensive guidelines for further research. Representative methods for calculating the depth of discharge of zn anodes with different structures are first summarized. The reasonable modification strategies of zn foil anodes, current collectors with pre-deposited zn, and anode-free aqueous zn metal batteries(AF-AzMBs) to improve zn utilization are then detailed. In particular, the working mechanism of AF-AzMBs is systematically introduced. Finally, the challenges and perspectives for constructing high-utilization zn anodes are presented.

关键词： Aqueous zinc metal batteries zinc anodes High zinc utilization Depth of discharge Anode-free structures

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Effects of longitudinal magnetic field on primary dendrite spacing and segregation of directionally solidified single crystal superalloy

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Progress in Natural Science:Materials International 2024年第1期34卷 26-36页

作者： Congjiang z.ang Yilin zhou Chen Shen Weili Ren Xiaotan Yuan Biao Ding Haibiao Lu zuosheng Lei Yunbo zhong ang z.ang State Key Laboratory of Advanced Special Steel College of Materials Science and Engineering Shanghai University National Engineering Research Center for Magnesium Alloys Natural Key Laboratory of Advanced Casting Technologies College of Materials Science and EngineeringChongqing University

The primary dendrite spacing(PDS) and segregation of directionally solidified single crystal(SC) superalloy under the longitudinal magnetic field(LMF) were investigated based on the analysis of the whole cross-sectional microstructure at different solidification distances. The results show that the PDS under the LMF remains basically unchanged at different solidification distances, and it is greater than that under no LMF. With the increase of magnetic field intensity, the PDS increases and the macrosegregation decreases. The increasing PDS and reducing segregation under the LMF can be attributed to the increase of solute boundary layer, which expands the non-equilibrium freezing temperature range and brings the effective partition coefficient closer to 1. The increase of the solute enrichment layer thickness could be caused by the downward secondary circulation generated by the thermoelectric magnetic convection(TEMC) near the interface, which drives the migration of solutes towards the interdendritic region. This work not only clarifies the mechanism of LMF controlling PDS and reducing segregation by TEMC, but also provides theoretical guidance for producing high-quality SC superalloys using magnetic fields.

关键词： Primary dendrite spacing Segregation Single crystal superalloy Directional solidification Magnetic field Thermoelectric magnetic convection

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