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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

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

Weighted Probability Density Estimator with Updated bandwidths

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Journal of Systems Science & Complexity 2024年第2期37卷 886-906页

作者： WU yi YU Wei WANG Xuejun PRAKASA RAO b L S School of big Data and Artificial Intelligence Chizhou UniversityChizhou 247000China School of big Data and Statistics Anhui UniversityHefei 230601China CR Rao Advanced Institute of Mathematics Statistics and Computer ScienceHyderabad 500046India

In this paper,the authors study a class of weighted version of probability density *** is shown that the weighted estimator contains some existing estimators of probability density,no matter they are recursive or *** statistical results including weak consistency,strong consistency,rate of strong consistency,and asymptotic normality are established under some mild ***,the random weighted estimator is also *** numerical simulations and a real data analysis are presented to study the numerical performances of the estimators.

关键词： Asymptotic normality consistency numerical simulation probability density real data analysis updated bandwidths weighted estimator

Rheological properties and concentration evolution of thickened tailings under the coupling effect of compression and shear

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 862-876页

作者： Aixiang Wu Zhenqi Wang Zhuen Ruan Raimund bürger Shaoyong Wang yi Mo Key Laboratory of the Ministry of Education of China for High-efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China CI2MA and Departamento de Ingeniería Matemática Facultad de Ciencias Físicas y MatemáticasUniversidad de ConcepciónCasilla 160-CConcepciónChile School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China China Railway Construction Tongguan Investment Co. Ltd.Tongling 244000China

Cemented paste backfill(CPb)is a key technology for green mining in metal mines,in which tailings thickening comprises the primary link of CPb ***,difficult flocculation and substandard concentrations of thickened tailings often *** rheological properties and concentration evolution in the thickened tailings remain ***,traditional indoor thickening experiments have yet to quantitatively characterize their rheological *** experiment of flocculation condition optimization based on the box-behnken design(bbD)was performed in the study,and the two response values were investigated:concentration and the mean weighted chord length(MWCL)of ***,optimal flocculation conditions were *** addition,the rheological properties and concentration evolution of different flocculant dosages and ultrafine tailing contents under shear,compression,and compression-shear coupling experimental conditions were tested and *** results show that the shear yield stress under compression and compression-shear coupling increases with the growth of compressive yield stress,while the shear yield stress increases slightly under *** order of shear yield stress from low to high under different thickening conditions is shear,compression,and compression-shear *** compression and compression-shear coupling,the concentration first rapidly increases with the growth of compressive yield stress and then slowly increases,while concentration increases slightly under *** order of concentration from low to high under different thickening conditions is shear,compression,and compression-shear ***,the evolution mechanism of the flocs and drainage channels during the thickening of the thickened tailings under different experimental conditions was revealed.

关键词： thickened tailings compression-shear coupling compressive yield stress shear yield stress concentration

In situ TEM investigation of electron irradiation and aging-induced high-density nanoprecipitates in an Mg-10Gd-3Y-1Zn-0.5Zr alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1841-1853页

作者： M.Lv H.L.Ge q.q.Jin X.H.Shao Y.T.Zhou b.Zhang X.L.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density precipitates in an Mg-10Gd-3Y-1Zn-0.5Zr(GWZ1031K,wt.%)alloy to improve the *** results show that the hardness of the Mg alloy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approximately 64% higher than that of the samples before being *** is mainly attributed to γ'precipitates on the basal plane after irradiation and the high-density nanoscale β'precipitates on the prismatic plane after aging,which should be closely related to the irradiation-induced homogenous *** latter plays a key role in precipitation *** result paves a way to improve the mechanical properties of metallic materials by tailoring the precipitation through irradiation and aging.

关键词： Mg alloy Electron beam irradiation Hardening Precipitates In-situ TEM

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan q.Wang Y.Chen W.b.Yao C.Z.Xiao J.F.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Shor's algorithm does not factor large integers in the presence of noise

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Science China(Information Sciences) 2024年第7期67卷 305-320页

作者： Jin-yi CAI College of Letters and Science University of Wisconsin

We consider Shor's quantum factoring algorithm in the setting of noisy quantum gates. Under a generic model of random noise for(controlled) rotation gates, we prove that the algorithm does not factor integers of the form pq when the noise exceeds a vanishingly small level in terms of n—the number of bits of the integer to be factored, where p and q are from a well-defined set of primes of positive density. We further prove that with probability 1-o(1) over random prime pairs(p, q), Shor's factoring algorithm does not factor numbers of the form pq, with the same level of random noise present.

关键词： random noise Shor's algorithm rotation gates quantum computing prime factorization

Effect of the yaw angle on turbulent flow structures around the submarine model

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Journal of Hydrodynamics 2024年第3期36卷 421-434页

作者： yi-jing Hu yi qu qin Wu biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China beijing Institute of Electronic System Engineering Beijing100854China

The objective of this paper is to investigate the turbulent flow structures around the submarine model and evaluate the effect of the yaw angle on the turbulent flow *** large eddy simulation based on the boundary data immersion method is used to *** computational domain consists of 1.2×10^(8)uniformly distributed Cartesian orthogonal grid nodes to capture the basic flow characteristics around the *** pressure coefficient,friction coefficient and wake velocity distribution are in good agreement with the experimental *** different types of vortex structures were mainly captured around the model,including horseshoe vortex,sail tip vortex and crossflow separation *** the increase of the yaw angle,the asymmetry of the horseshoe vortex and the tip vortex gradually increases,and the vortex strength of the vortex leg on the windward of the horseshoe vortex and the vortex strength of the tip vortex also increase *** the crossflow separation vortex,the flow separation zone gradually expands and migrates downstream with the increase of the yaw angle.

关键词： Vortex structure submarine model boundary data immersion method yaw angle

The design and performance of charged particle detector onboard the GECAM mission

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Radiation Detection Technology and Methods 2022年第1期6卷 53-62页

作者： Y.b.Xu X.q.Li X.L.Sun S.Yang H.Wang W.X.Peng X.H.Liang K.Gong Y.q.Liu D.Y.Guo X.Y.Zhao C.Y.Li Z.H.An J.J.He X.J.Liu X.Y.Wen S.L.Xiong Fan Zhang D.L.Zhang C.Y.Zhang C.Cai Z.Chang G.Chen C.Chen Y.Y.Du M.Gao R.Gao D.J.Hou Y.G.Li G.Li L.Li X.F.Li M.S.Li F.J.Lu H.Lu b.Meng F.Shi J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao Y.P.Xu J.W.Yang q.b.yi S.N.Zhang C.M.Zhang F.Zhang Y.Zhao X.Zhou Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

background The Gravitational wave highly energetic Electromagnetic Counterpart All-sky Monitor(GECAM)is dedicated to detecting gravitational wave gamma-ray *** is capable of all-sky monitoring over and discovering gamma-ray bursts and new radiation *** consists of two microsatellites,each equipped with 8 charged particle detectors(CPDs)and 25 gamma-ray detectors(GRDs).Purpose The CPD is used to measure charged particles in the space environment,monitor energy and flow intensity changes,and identify between gamma-ray bursts and space charged particle events in conjunction with *** CPD uses plastic scintillator as the sensitive material for detection,silicon photomultiplier array as the optically readable device,and the inlaid Am-241 radioactive source as the onboard calibration *** In this paper,we will present the working principle,physical design,functional implementation and preliminary performance test results of the *** a result,the energy range of electron,gamma-ray detection efficiency and dead time are tested to be better than the indexes required through the ground calibration experiment.

关键词： GECAM CPD SiPM