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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

Synthesis and characterization of nanocarbon from waste batteries via an eco-friendly method

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Waste Disposal and Sustainable Energy 2024年第2期6卷 197-208页

作者： Maraim Kh.Uoda Hussein q.Hussein rana r.Jalil Chemical Engineering Department College of EngineeringUniversity of BaghdadBaghdadIraq Thi.qar Oil Company NassriyaIraq Petroleum research and Development Center BaghdadIraq

The widespread use of disposable batteries to power common electronic devices is a major source of *** are growing environmental and health concerns due to the expansion of e-waste around the ***,developing a reli-able system for recycling old batteries has reached the top of the recycling priority *** current study presents a novel approach to synthesis carbon nanoparticles(CNPs)from spent batteries via an eco-friendly method that offers economical,environment-friendly,and nontoxic approaches in comparison to conventional chemical *** synthesized nano-particles were characterized by field emission scanning electron microscopy(FE-SEM),energy-dispersive X-ray(EDX),powder X-ray diffractometry(XrD),UV-VIS absorption analysis(UV),Fourier transform infrared spectroscopy(FT-Ir),Atomic force microscope(AFM),and thermo-gravimetric analysis(TGA).The average diameter of the synthesized particles was 40.16 nm,and the particles tended to be aspherical in *** analysis also predicted the presence of pure carbon,with some contamination arrived at 15%(in weight).This is a novel study in which nanocarbons were synthesized in a brine(7600x10-6)from a target(CNPs>75 nm),which paves the way for future use of CNPs derived from spent batteries and helps the environment by decreasing the amount of electronic waste dumped in landfills.

关键词： Novel Zn-C battery Carbon nanoparticles Characterization Eco-friendly methods

Topological magnetoelectric response in ferromagnetic axion insulators

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National Science review 2024年第2期11卷 8-14页

作者： Yuhao wan Jiayu Li qihang Liu Department of Physics and Shenzhen Institute for quantum Science and Engineering(SIqSE) Southern University of Science and Technology Shenzhen Key Laboratory of Advanced quantum Functional Materials and Devices Southern University of Science and Technology Guangdong Provincial Key Laboratory for Computational Science and Material Design Southern University of Science and Technology

The topological magnetoelectric effect （TME） is a hallmark response of the topological field theory,which provides a paradigm shift in the study of emergent topological ***,its direct observation is yet to be realized due to the demanding magnetic configuration required to gap all surface ***,we theoretically propose that axion insulators with a simple ferromagnetic configuration,such as the MnBi2Te4/（Bi2Te3）nfamily,provide an ideal playground to realize the *** the designed triangular prism geometry,all the surface states are magnetically *** a vertical electric field,the surface Hall currents give rise to a nearly half-quantized orbital moment,accompanied by a gapless chiral hinge mode circulating in ***,the orbital magnetization from the two topological origins can be easily distinguished by reversing the electric *** work paves the way for direct observation of the TME in realistic axion-insulator materials.

关键词： topological magnetoelectric effect axion insulator magnetic topological materials

Optimal regularity of positive solutions of the Hénon-Hardy equation and related equations

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Science China Mathematics 2024年第10期67卷 2283-2302页

作者： Zongming Guo Fangshu wan College of Mathematics and Information Science Henan Normal UniversityXinxiang 453007China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China School of Mathematical Sciences Anhui UniversityHefei 230601China

We present a new method to determine the optimal regularity of positive solutions u∈C^(4)(Ω\r)∩C^(0)(Ω) of the Hénon-Hardy equation,i.e.,Δ^(2)u=|x|^(α)u^(p)inΩ,(0,1) where Ω■rN(N≥4) is a bounded smooth domain with 0∈Ω,α>-4,and p∈*** is clear that 0 is an isolated singular point of solutions of(0.1) and the optimal regularity of u in Ω relies on the parameter α.It is also important to see that the regularity of u at x=0 determines the regularity of u in Ω.We first establish asymptotic expansions up to arbitrary orders at x=0 of prescribed positive solutions u ∈C^(4)(Ωr) ∩ C^(0)(Ω)of(0.1).Then we show that the regularity at x=0 of each positive solution u of(0.1) can be determined by some terms in asymptotic expansions of the related positive radial solution of the equation(0.1) with Ω=B,where B is the unit ball of r^(N).The main idea works for more general equations with singular weights.

关键词： H´enon-Hardy equation positive solutions optimal regularity singular point asymptotic expansions

Some rotundities of Orlicz–Lorentz Spaces

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1893-1919页

作者： wan Zhong GONG Peng wanG Department of Mathematics Anhui Normal UniversityWuhu 241000P.R.China

K-Ur,K-LUr and K-r are the generalizations of Ur,LUr and r respectively,which are of great significance in Banach space *** in Orlicz–Lorentz function spaceΛ_(ϕ,ω)^(◦)[0,γ)equipped with the Orlicz norm,the research methods of K-Ur,K-LUr and K-r are much more complicated than those of Ur,LUr and *** this paper we obtain some criteria of K-Ur,K-LUr and K-r ofΛ_(ϕ,ω)^(◦)[0,γ)by means of the norm of dual space and H_(μ)property ofΛ_(ϕ,ω)^(◦)[0,γ).

关键词： Orlicz-Lorentz space Orlicz norm k-uniform rotundity locally k-uniform rotundity krotundity

Evaluating changes in business distribution within urban rail transit hubs in Beijing via Point of Interest (POI) data analysis (2008-2020)

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Frontiers of Architectural research 2024年第2期13卷 305-318页

作者： Bo wan Dongyang wan qiang Sheng School of Architecture and Design Beijing Jiaotong UniversityBeijing 100044China

This paper,set against the backdrop of expanding urban rail networks and dynamic urban development,focuses on the distribution and evolution of commercial Points of Interests(POIs)within the central urban rail transit areas of *** study examines data from four different years-2008,2013,2017,and 2020-to observe the temporal evolution of commercial *** identifies stable explanatory variables affecting the distribution and evolution of commercial POIs,which include rail transit accessibility,characteristics of the working and residential population distribution around stations,and the construction intensity in the vicinity of station *** statistical analysis and model building,relatively stable linear regression equations were established,with r2 values generally maintained above 0.5(except for 2017).The study advances our understanding of the influence of rail transit on urban commercial spaces and how this influence shifts with temporal and urban developmental *** elucidates the correlation between changes in the number of businesses and spatial configuration,offering insights and information for urban planners and policy *** research also serves as a model for exploring the interplay between urban rail transit and commercial spaces in other major cities.

关键词： Urbanrail transit areas Spatial configuration Distributionand evolution of commercial POls

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

Electron kinetic effects in back-stimulated raman scattering bursts driven by broadband laser pulses

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Matter and radiation at Extremes 2024年第4期9卷 54-67页

作者： q.K.Liu L.Deng q.wang X.Zhang F.q.Meng Y.P.wang Y.q.Gao H.B.Cai S.P.Zhu Graduate School China Academy of Engineering PhysicsBeijing 100088China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China Shanghai Institute of Laser Plasma Shanghai 201800China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China School of Physics Zhejiang UniversityHangzhou 310027China

We examine electron kinetic effects in broadband-laser-driven back-stimulated raman scattering(BSrS)bursts using particle-in-cell *** bursts occur during the nonlinear stage,causing reflectivity spikes and generating large numbers of hot ***-duration simulations are performed to observe burst events,and a simplified model is developed to eliminate the interference of the broadband laser’s random intensity *** the simplified model,we isolate and characterize the spectrum of electron plasma *** spectrum changes from a sideband structure to a turbulence-like structure during the burst.A significant asymmetry in the spectrum is *** asymmetry is amplified and transferred to electron phase space by high-intensity broadband laser pulses,leading to violent vortex-merging and generation of hot *** proportion of hot electrons increases from 6.76%to 14.7%during a single violent burst *** demonstrate that kinetic effects profoundly influence the BSrS evolution driven by broadband lasers.

关键词： scattering kinetic simplified

Hollow Multi-shelled Structure Photoelectric Materials: Multiple Shells Bring Novel Properties

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Chemical research in Chinese Universities 2024年第3期40卷 413-427页

作者： SU Fengmei wan Jiawei wanG Dan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese AcademyofSciencesBeijing 100049P.R.China

Hollow multi-shelled structures(HoMSs)have made significant strides across a wide spectrum of scientific investigations since the inception of the sequential templating approach(STA)in 2009,revealing distinctive temporal-spatial ordering *** recent establishment of a mathematical model for STA has not only demystified the formation of concentration waves within the STA process but also extended its relevance to gentler solutionbased systems,thereby broadening the HoMs ***,focusing on photoelectric applications,this review first summarizes the unique temporal-spatial ordering features of ***,the greatly enhanced properties of light capture and absorption,exciton separation,and transfer are deeply ***,we conclude with a perspective on the potential challenges and burgeoning opportunities that lie ahead in the advancement of HoMs development.

关键词： Hollow multi-shelled structure Photoelectric conversion Sequential templating approach Light absorption Chargetransfer