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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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Local MFs Matrix Decomposition Algorithms for Elliptic BVPs in Annuli

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NUMErIcAL MATHEMATIcs-THEOrY METHODs AND APPLIcATIONs 2024年第1期17卷 93-120页

作者： chen, c. s. Karageorghis, Andreas Lei, Min Univ southern Mississippi Sch Math & Nat Sci Hattiesburg MS 39406 USA Univ cyprus Dept Math & Stat POB 20537 CY-1678 Nicosia Cyprus Taiyuan Univ Technol Coll Math Taiyuan 030024 Peoples R China

We apply the local method of fundamental solutions (LMFs) to boundary value problems (BVPs) for the Laplace and homogeneous biharmonic equations in annuli. By appropriately choosing the collocation points, the LMFs discretization yields sparse block circulant system matrices. As a result, matrix decomposition algorithms (MDAs) and fast Fourier transforms (FFTs) can be used for the solution of the systems resulting in considerable savings in both computational time and storage requirements. The accuracy of the method and its ability to solve large scale problems are demonstrated by applying it to several numerical experiments.

关键词： Local method of fundamental solutions Poisson equation biharmonic equation matrix decomposition algorithms fast Fourier transforms BOUNDArY-VALUE-PrOBLEMs FUNDAMENTAL-sOLUTIONs rBF ALGOrITHMs

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Limited impacts of occasional tillage on dry aggregate size distribution and soil carbon and nitrogen fractions in semi-arid drylands

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International soil and Water conservation research 2024年第1期12卷 96-106页

作者： Wooiklee s.Paye Vesh r.Thapa rajan Ghimire New Mexico state University Agricultural Science CenterClovisNM88101USA New Mexico state University Department of Plant and Environmental SciencesLas CrucesNM88003USA

Tillage management that minimizes the frequency and intensity of soil disturbance can increase soil carbon(c)and nitrogen(N)sequestration and improve the resilience of dryland cropping systems,yet the impact of occasional disturbance on soil aggregate formation and the soil organic carbon(sOc)storage within aggregates has not been studied *** evaluated the effect of four tillage management practices on soil dry aggregate size distribution,aggregate-protected c and N,mineral-associated organic matter carbon(MAOM-c),particulate organic matter carbon(POM-c),and corn(Zea mays L.)and sorghum(sorghum bicolor(L.)Moench)yields in a semi-arid dryland cropping *** included conventional tillage(cT),strip-tillage(sT),no-tillage(NT),and occasional tillage(OT)management in a corn-sorghum *** macro-aggregates were 51-54%greater under sT,NT,and OT,while small and micro-aggregates were greater in *** tillage reduced soil aggregate-associated c by 28-31%in macro-aggregates and 47-53%in small aggregates at 26 months(M)sampling compared to sT,NT,and *** clay+silt fraction,cT had 14-16%,21-26%,and 36-43%less sOc at 7,14,and 26M samplings,respectively,than sT,NT,and *** associated N was generally similar under sT,NT,and OT,which was greater on average than *** MOAM-c and POM-c under sT,NT,and OT were generally greater than respective sOc fractions under cT at 19 and 26 M after OT *** and sorghum yields were similar among tillage systems in 2020,but greater under sT,NT,and OT than cT in *** results suggest that while frequent intensive tillage can lower.s.c.and N storage,a single stubble mulch occasional tillage after several years of NT does not lead to soil c and N losses and soil structural instability in semi-arid drylands.

关键词： conventional tillage Occasional tillage Aggregate associated carbon Mineral associated organic matter carbon(MAOM-c) Particulate organic matter carbon(POM-c)

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Atomistic Investigation of shock-Induced Amorphization within Micro-shear Bands in Hexagonal close-Packed Titanium

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Acta Metallurgica sinica(English Letters) 2024年第9期37卷 1590-1600页

作者： Z.c.Meng K.G.Wang T.Ali D.Li c.G.Bai D.s.Xu s.J.Li A.H.Feng G.J.cao J.H.Yao Q.B.Fan H.Wang r.Yang Institute of Metal research Chinese Academy of SciencesShenyang 110016China school of Materials science and Engineering University of Science and Technology of ChinaShenyang 110016China Interdisciplinary centre for Additive Manufacturing(IcAM) School of Materials and ChemistryUniversity of Shanghai for Science and TechnologyShanghai 200093China school of Materials science and Engineering Tongji UniversityShanghai 201804China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China National Key Laboratory of science and Technology on Materials Under shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology chongqing Innovation center Chongqing 401135China

The mechanical response of a single crystal titanium sample against(0001)α surface impact was investigated using molecular dynamics ***,non-uniform plastic deformation was observed in the *** high strain rates,amorphization occurred near the edge of the contact region where severe shear strain induced a large number of stacking faults(sFs)and *** contrast,the central part of the contact region underwent less deformation with significantly fewer ***,instead of amorphization by consuming sFs and dislocations,there was a gradual increase in the density of dislocations and sFs during the process of *** local amorphous regions eventually grew into shear bands.

关键词： shock compression Amorphization shear band Titanium Molecular dynamics

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A global analysis of the introduction pathways and characteristics associated with non-native fish species introduction, establishment, and impacts

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Ecological Processes 2024年第2期13卷 16-31页

作者： camille Bernery céline Bellard Franck courchamp sébastien Brosse Boris Leroy cNrs Agro Paris Tech Ecologie Systématique Evolution Université Paris-Saclay Unité Biologie des Organismes et Ecosystèmes Aquatiques (BOrEA UMr 8067) Muséum National d’Histoire Naturelle Sorbonne Universités Université de Caen Normandie Université des Antilles CNRS IRD Laboratoire évolution & Diversité Biologique (EDB UMr5174) Université Paul Sabatier-Toulouse 3 CNRS IRD UPS

Background The invasion success of introduced freshwater fishes is influenced by many factors, including ecological, species, and socioeconomic characteristics. Most studies that document the importance of these characteristics are conducted at local scales and/or focus on a single step of the invasion process. In this study, we aim to determine the species characteristics, ecological characteristics, and socioeconomic characteristics of non-native freshwater fish invasions. Our assessment was done at the global scale and considers all three steps of the invasion(i.e., introduction, establishment, and impact). For this purpose, we applied generalized linear models to 20 variables collected for 307 non-native species and modeled them as a function of ecological characteristics(i.e., environmental features), species traits(i.e., functional and morphological), and socioeconomic characteristics(i.e., human use and introduction pathways). We considered the number of countries in which each species was introduced, established, or had ecological impacts as a proxy of invasion step success. We also explored the specifics of species introduced through the aquaculture and the ornamental fish trade *** We found that non-native freshwater fishes with broad diets, high parental care, and multiple introduction pathways are the most widely introduced and established worldwide. The number of countries with impacts reported was best explained by the type of introduction pathway(i.e., aquaculture or fisheries). Moreover, among non-native species introduced through aquaculture, those belonging to cypriniformes and having broad diets were the most widely introduced and established species. In contrast, the species introduced through the ornamental fish trade pathway belonged to various taxonomic orders but were mainly native to tropical *** considering several types of factors is important when analyzing the invasion success of freshwater fish and disentang

关键词： Aquaculture Ecology Exotic Freshwater fish Introduction pathway Invasion step Morphology Ornamental fish trade socioeconomic Trait

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All-electron basis sets for H to Xe specific for ZOrA calculations:Applications in atoms and molecules

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chinese Physics B 2024年第8期33卷 238-246页

作者： c.s.Gomes F.E.Jorge A.canal Neto Departamento de Fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de Fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZOrA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZOrA-ccsD(T)/QZP-ZOrA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZOrA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZOrA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZOrA and AQZP-ZOrA basis sets elements from H to Xe ccsD(T)method atomic and molecular properties

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Multinuclear Mr and MrI study of lithium-ion cells using a variable field magnet and a fixed frequency rF probe

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Magnetic resonance Letters 2024年第1期4卷 10-20页

作者： Andrés ramírez Aguilera Florin Marica Kevin J.sanders Md Al raihan c.Adam Dyker Gillian r.Goward Bruce *** UNB MrI centre Department of PhysicsUniversity of New BrunswickFrederictonNew BrunswickE3B 5A3Canada Department of chemistry McMaster UniversityHamiltonOntarioL8S 4L8Canada Department of chemistry University of New BrunswickFrederictonNew BrunswickE3B 5A3Canada

An exploratory multinuclear magnetic resonance(Mr)and magnetic resonance imaging(MrI)study was performed on lithium-ion battery cells with ^(7)Li,^(19)F,and ^(1)H measurements.A variable field superconducting magnet with a fixed frequency parallel-plate radiofrequency(rF)probe was employed in the *** magnetic field was changed to set the resonance frequency of each nucleus to the fixed rF probe frequency of 33.7 *** cartridge-like lithium-ion cells,with graphite anodes and LiNi_(0.5)Mn_(0.3)co_(0.2)O_(2)(NMc)cathodes,were *** cell was pristine,and one was charged to a cell voltage of 4.2 *** results presented demonstrate the great potential of the variable field magnet approach in multinuclear measurement of lithium-ion *** methods open the door for developing faster and simpler methods for detecting,quantifying,and interpreting Mr and MrI data from lithium-ion and other batteries.

关键词： Multinuclear Mr/MrI Variable field magnet Lithium-ion battery Parallel-plate rf probe

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Effect of radiative loss mechanisms on FIr thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.L silva L.A.O.Nunes s.M.Lima L.H.c.Andrade Optical and Photothermal spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of são carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIr)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIr parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt rare earths

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synthesis of coral-like structures of Pr-Yb co-doped YIG: structural,optical, magnetic and antimicrobial properties

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Journal of rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra s.castro-Lopes J.Matilla-Arias Idglan s.de Lima Edson c.silva-Filho Josy A.Osajima F.Guerrero r.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIr) and raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDs) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against s. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) coral-like structures rare earths Band gap energy Magnetic properties Antimicrobial properties

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rotating effects on the photoionization cross-section of a 2D quantum ring

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communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： carlos Magno O Pereira Frankbelson dos s Azevedo Luís Fernando c Pereira Edilberto O silva Departamento de Física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoionization cross-section quantum ring rotating effect

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