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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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Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： S.w.wi y.S.Lee Department of Physics and Integrative Institute of Basic Sciences Soongsil University

we investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence Sensitizer Rare earths

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Superconductivity Bordering Rashba Type Topological Transition

Superconductivity Bordering Rashba Type Topological Transiti...

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中国晶体学会第六届学术年会暨会员代表大会（极端条件晶体材料分会）

作者： M.L.Jin F.Sun L.y.Xing S.J.Zhang S.M.Feng P.P.Kong w.M.Li X.C.wang J.L.Zhu y.w.long H.y.Bai C.Z.Gu R.C.yu w.G.yang G.y.Shen y.S.Zhao H.K.Mao C.Q.Jin Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences HiPSEC Department of Physics and AstronomyUniversity of Nevada at Las Vegas High Pressure Synergetic Consortium (HPSynC) & High Pressure Collaborative Access Team (HPCAT) Geophysical LaboratoryCarnegie Institution of Washington Center for High Pressure Science & Technology Advanced Research (HPSTAR)

Strong spin orbital interaction(SOI)can induce unique quantum phenomena such as topological insulators,the Rashba effect,or p-wave *** these three quantum phenomena into a single compound has important scientific *** ...

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Superconductivity in HfTe5 across weak to strong topological insulator transition induced via pressures

Superconductivity in HfTe5 across weak to strong topological...

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中国晶体学会第六届学术年会暨会员代表大会（极端条件晶体材料分会）

作者： y.Liu y.J.long L.X.Zhao S.M.Nie S.J.Zhang y.X.weng M.L.Jin w.M.Li Q.Q.Liu y.w.long R.C.yu C.Z.Gu F.Sun w.G.yang H.K.Mao X.L.Feng Q Li w.T.Zheng H.M.weng X.Dai Z.Fang G.F.Chen C.Q.Jin Institute of Physics Chinese Academy of Sciences Center for High Pressure Science & Technology Advanced Research Department of Materials Science Jilin University Collaborative Innovation Center of Quantum Matter

Recently,theoretical studies show that layered Hf Te5is at the boundary of weak&strong topological insulator(TI)and might crossover to a Dirac semimetal state by changing lattice *** topological properties of 3D stack...

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Photocatalytic activation of sulfite by N-doped porous biochar/MnFe_(2)O_(4) interface-driven catalyst for efficient degradation of tetracycline

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Green Energy & Environment 2024年第3期9卷 481-494页

作者： long Cheng yuanhui Ji Jiangsu Province Hi-Tech Key Laboratory for Biomedical Research School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing211189China

A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous *** adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic ***,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical *** the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.

关键词： Biochar MnFe_(2)O_(4) Sulfite Adsorption Photocatalysis

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Prediction model for corrosion rate of low-alloy steels under atmospheric conditions using machine learning algorithms

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 337-350页

作者： Jingou Kuang Zhilin long School of Civil Engineering Xiangtan UniversityXiangtan 411105China

This work constructed a machine learning(ML)model to predict the atmospheric corrosion rate of low-alloy steels(LAS).The material properties of LAS,environmental factors,and exposure time were used as the input,while the corrosion rate as the output.6 dif-ferent ML algorithms were used to construct the proposed *** optimization and filtering,the eXtreme gradient boosting(XG-Boost)model exhibited good corrosion rate prediction *** features of material properties were then transformed into atomic and physical features using the proposed property transformation approach,and the dominant descriptors that affected the corrosion rate were filtered using the recursive feature elimination(RFE)as well as XGBoost *** established ML models exhibited better predic-tion performance and generalization ability via property transformation *** addition,the SHapley additive exPlanations(SHAP)method was applied to analyze the relationship between the descriptors and corrosion *** results showed that the property transformation model could effectively help with analyzing the corrosion behavior,thereby significantly improving the generalization ability of corrosion rate prediction models.

关键词： machine learning low-alloy steel atmospheric corrosion prediction corrosion rate feature fusion

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Frequency Domain Fatigue Evaluation on SCR Girth-weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： ZHANG long ZHAO Tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

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Designing Proportional-Integral Consensus Protocols for Second-Order Multi-Agent Systems Using Delayed and Memorized State Information

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 878-892页

作者： Honghai wang Qing-long Han the College of Information Science and Engineering State Key Laboratory of Synthetical Automation for Process IndustriesNortheastern UniversityShenyang 110819China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourneVIC 3122Australia

This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consensus protocol is designed by using delayed and memorized state *** the proportional-integral consensus protocol,the consensus problem of the multi-agent system is transformed into the problem of asymptotic stability of the corresponding linear time-invariant time-delay *** that the location of the eigenvalues of the corresponding characteristic function of the linear time-invariant time-delay system not only determines the stability of the system,but also plays a critical role in the dynamic performance of the *** this paper,based on recent results on the distribution of roots of quasi-polynomials,several necessary conditions for Hurwitz stability for a class of quasi-polynomials are first *** allowable regions of consensus protocol parameters are *** necessary and sufficient conditions for determining effective protocol parameters are *** designed protocol can achieve consensus and improve the dynamic performance of the second-order multi-agent ***,the effects of delays on consensus of systems of harmonic oscillators/double integrators under proportional-integral consensus protocols are ***,some results on proportional-integral consensus are derived for a class of high-order linear time-invariant multi-agent systems.

关键词： Consensus protocol Hurwitz stability multi-agent systems quasi-polynomials time delay

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Automatic modeling algorithm of stochastic error for inertial sensors

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Control Theory and Technology 2024年第1期22卷 81-91页

作者： Luodi Zhao long Zhao School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Digital Navigation Center Beihang UniversityBeijing100191China Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing100191China

This paper proposes an automatic algorithm to determine the properties of stochastic processes and their parameters for inertial error. The proposed approach is based on a recently developed method called the generalized method of wavelet moments (GMwM), whose estimator was proven to be consistent and asymptotically normally distributed. This algorithm is suitable mainly (but not only) for the combination of several stochastic processes, where the model identification and parameter estimation are quite difficult for the traditional methods, such as the Allan variance and the power spectral density analysis. This algorithm further explores the complete stochastic error models and the candidate model ranking criterion to realize automatic model identification and determination. The best model is selected by making the trade-off between the model accuracy and the model complexity. The validation of this approach is verified by practical examples of model selection for MEMS-IMUs (micro-electro-mechanical system inertial measurement units) in varying dynamic conditions.

关键词： GMwM Stochastic process Inertial sensor Sensor calibration Error model Allan variance

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One bird,multiple stones:The race to find a gene of dominant negative effect in wheat

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The Crop Journal 2024年第4期12卷 951-952页

作者： long Mao State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China

In the current issue of The Crop Journal,Chen et al.[1]reports map-based cloning of a wheat gene that showed temperaturedependent pleiotropic effects on multiple traits including plant height,leaf shape,spike and grain morphology,and accordingly was named wPA1 for wheat Plant Architecture *** mutant was first observed among EMS-treated plants and repeatedly appeared in multiple occasions.

关键词： wheat bird repeatedly

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