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Wave equation for anyons and its exact solutions in external fields

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science China Mathematics 1997年第10期40卷 1103-1109页

作者：吕景发 s.i.kruglov 赵学庆 Department of Physics Nankai UniversityTianjin 300071China

By using the gauge-invariance,a Klein-Gordon’s type equation for anyons in external fields is constructed.The equation can be solved exactly in a constant electric and magnetic field,as well as in a quantized electro... 详细信息

关键词： anyon wave equation exact solutions.

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外场中任意子的相对论波动方程及其严格解

中国科学（A辑） 1997年第7期27卷 646-652页

作者：吕景发赵学庆 s.i.kruglov 南开大学物理系天津300071 白俄罗斯科学院物理研究所

利用规范不变性,构造了一个任意子在外场中的波动方程,即自旋局域且规范不变的1+2维Klein-Gordon型粒子方程。并发现,外场无论是静电场、还是静磁场以及量子化的电磁场,该方程是严格可解的。给出了相应的解析解形式。

关键词：任意子波动方程严格可解外场相对论

Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr s.slavich Georgy A.Ermolaev Mikhail K.Tatmyshevskiy Adilet N.Toksumakov Olga G.Matveeva Dmitriy V.Grudinin Kirill V.Voronin Arslan Mazitov Konstantin V.Kravtsov Alexander V.syuy Dmitry M.Tsymbarenko Mikhail s.Mironov sergey M.Novikov ivan kruglov Davit A.Ghazaryan Andrey A.Vyshnevyy Aleksey V.Arsenin Valentyn s.Volkov Kostya s.Novoselov Moscow Center for Advanced studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia international Physics Center(DiPC) Donostia/San-Sebastián 20018Spain. institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. National Graphene institute(NGi) University of ManchesterManchester M139PLUK. Department of Materials science and Engineering National University of SingaporeSingapore 03-09 EASingapore. institute for Functional intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and applications.such success inspired an intensive search for the highest possible anisotropic properties among vdW materials.Furthermore,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative approaches.Here,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical characterization.Using our approach,we found As2s3 as a highly anisotropic vdW material.it demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by rutile.Given these benefits,As2s3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–Pérot optical phase accumulations.Hence,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

A statistical study of Magnetic Flux Emergence in solar Active Regions Prior to strongest Flares

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Research in Astronomy and Astrophysics 2024年第4期24卷 147-160页

作者： Alexander s.Kutsenko Valentina i.Abramenko Andrei A.Plotnikov Crimean Astrophysical Observatory p/o NauchnyCrimea298409Russia

Using the data on magnetic field maps and continuum intensity for solar Cycles 23 and 24,we explored 100 active regions(ARs)that produced M5.0 or stronger flares.We focus on the presence/absence of the emergence of magnetic flux in these ARs 2-3 days before the strong flare onset.We found that 29 ARs in the sample emerged monotonically amidst quiet-sun.A major emergence of a new magnetic flux within a pre-existing AR yielding the formation of a complex flare-productive configuration was observed in another 24 cases.For 30 ARs,an insignificant(in terms of the total magnetic flux of pre-existing AR)emergence of a new magnetic flux within the pre-existing magnetic configuration was observed;for some of them the emergence resulted in a formation of a configuration with a small δ-sunspot;11 out of 100 ARs exhibited no signatures of magnetic flux emergence during the entire interval of observation.in six cases the emergence was in progress when the AR appeared on the Eastern limb,so that the classification and timing of emergence were not possible.We conclude that the recent flux emergence is not a necessary and/or sufficient condition for strong flaring of an AR.The flux emergence rate of flare-productive ARs analyzed here was compared with that of flare-quiet ARs analyzed in our previous studies.We revealed that the flare-productive ARs tend to display faster emergence than the flare-quiet ones do.

关键词： sun:activity sun:flares sun:magnetic fields

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2)-xO_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： i.sardar M.D.Hossain M.s.sikder M.N.i.Khan M.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh Material science Division Atomic Energy CentreDhaka1000Bangladesh

spinel cubic ferrites have huge applications in me mory and high frequency devices.For the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important issues.This article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2)-xO_(4) ferrites,where x=0.00,0.06,and 0.10.The X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTiR),field emission scanning electron microscopy(FEsEM),energy dispersive X-ray(EDX),vibrating sample magnetometer(VsM),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the samples.The XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped samples.The densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu concentration.The FTiR analysis also proves the spinel cubic phase of the samples.The average grain size of the ferrites is obtained via FEsEM images,and it is increased from 121 to 198 nm.VsM analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2)-xO_(4) ferrites.Particularly,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the ferrites.The permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric losses.Frequency dependent resistivity and impedance analysis also show the improved nature.From the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

A review of control strategies used for morphing aircraft applications

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Chinese Journal of Aeronautics 2024年第4期37卷 436-463页

作者： Muhammed s.PARANCHEERiViLAKKATHiL Jafar s.PiLAKKADAN Rafic M.AJAJ Mohammadreza AMOOZGAR Davood AsADi Yahya ZWEiRi Michael i.FRisWELL Department of Aerospace Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Aerospace Engineering Advanced Research and Innovation Center(ARIC)Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Mechanical Materials&Manufacturing EngineeringUniversity of NottinghamNottingham NG72RDUK Department of Aerospace Engineering Adana Alparslan Turkes Science and Technology UniversityTurkey College of Engineering Swansea UniversitySwansea SA18ENUK

This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. it is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. The first area is related to precise control of the shape of morphing concepts for various flight conditions. The second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. The third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. in addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. The aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low Technology Readiness Level(TRL) to real-life applications. This critical review aims to identify research gaps and propose future directions. in this paper, research activities/papers are categorized according to the control strategy used. This ranges from simple Proportional integral Derivative(PiD) controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. This includes analytical, computational, and experimental studies. in addition, the various dynamic models used and their fidelities are highlighted and discussed.

关键词： Control strategies Morphing aircraft shape morphing Flight dynamics Aeroelasticity

Antibacterial HA-coatings on bioresorbable Mg alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.V.Nadaraia D.V.Mashtalyar M.A.Piatkova A.i.Pleshkova i.M.imshinetskiy M.s.Gerasimenko E.A.Belov V.V.Kumeiko D.N.Kozyrev K.A.Fomenko V.V.Mostovaya B.R.Torpanov A.R.Biktimirov i.s.Osmushko s.L.sinebryukhov s.V.Gnedenkov institute of Chemistry FEB RAs Far Eastern Federal University A.V.Zhirmunsky National scientific Center of Marine Biology FEB RAs Regional Clinical Dermatovenerological Dispensary NMiC “Treatment and Rehabilitation Center”

in this study, a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PEO). The antibiotic vancomycin, widely used in the treatment of infections caused by staphylococcus aureus(s. aureus), was impregnated into the coating.samples with vancomycin showed high bactericidal activity against s. aureus. The mechanical and electrochemical properties of the formed coatings were studied, as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were performed. According to sEM,EDs, XRD and XPs data, coatings had a developed morphology and contained hydroxyapatite, which indicates high biocompatibility.The analysis of roughness of coatings without and with vancomycin did not reveal any differences, confirming the high roughness of the samples. During electrochemical tests, an increase in corrosion resistance by more than two times after the application of PEO coatings was revealed. According to the results of an in vivo study, after 28 days of the implantation of samples with calcium phosphate PEO coating and vancomycin, no signs of inflammation were observed, while an inflammatory reaction developed in the area of implantation of bare alloy,followed by encapsulation. Antibiotic release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day 28. Throughout the experiment, no significant deviations in the condition and behavior of the animals were observed; clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility Mg alloy Plasma electrolytic oxidation Hydroxyapatite Vancomycin

Nanomotion of bacteria to determine metabolic profile

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Nanotechnology and Precision Engineering 2024年第1期7卷 1-9页

作者： s.N.Pleskova E.V.Lazarenko N.A.Bezrukov R.N.Kriukov A.V.Boryakov M.E.Dokukin s.i.surodin Research Laboratory of scanning Probe Microscopy Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia Department of Nanotechnology and Biotechnology Nizhny Novgorod State Technical University n.a.R.E.AlekseevNizhny Novgorod 603950Russia sarov Physics and Technology institute National Research Nuclear University MEPhISarov 607186Russia

in addition to their visible motion such as swimming(e.g.,with the help ofﬂagella),bacteria can also exhibit nanomotion that is detectable only with highly sensitive instruments,and this study shows that it is possible to detect bacterial nanomotion using an AFM detection system.The results show that the nanomotion characteristics depend on the bacterial strain,and that nanomotion can be used to sense the metabolic activity of bacteria because the oscillations are sensitive to the food preferences of the bacteria and the type of surrounding medium.

关键词： Nanomotion Bacteria Cantilever Oscillation Atomic force microscopy Metabolism

An investigation into Forced Convection of a Nanofluid Flowing in a Rectangular Microchannel under the influence of a Magnetic Field

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Fluid Dynamics & Materials Processing 2024年第2期20卷 311-323页

作者： Muataz s.Alhassan Ameer A.Alameri Andrés Alexis Ramírez-Coronel i.B.sapaev Azher M.Abed David-Juan Ramos-Huallpartupa Rahman s.Zabibah Division of Advanced Nanomaterial Technologies Scientific Research CenterAl-Ayen UniversityThi-QarIraq Department of Chemistry College of ScienceUniversity of BabylonBabylonIraq Research Group in Educational statistics National University of EducatiosnAzoguesEcuador Department Physics and Chemistry Tashkent Institute of Irrigation and Agricultural Mechanization EngineersNational Research UniversityTashkentUzbekistan Akfa University TashkentUzbekistan New Uzbekistan University TashkentUzbekistan Department of Airconditioning and Refrigeration Engineering Al-Mustaqbal University CollegeHilla51001Iraq Academic Department of Agro-industrial Engineering and Technology Universidad Nacional JoséMaría ArguedasApurimacPerú The islamic University NajafIraq

in line with recent studies,where it has been shown that nanoﬂuids containing graphene have a stronger capacity to boost the heat transfer coefﬁcient with respect to ordinary nanoﬂuids,experiments have been conducted using water with cobalt ferrite/graphene nanoparticles.in particular,a circular channel made of copper subjected to a constant heatﬂux has been considered.As nanoparticles are sensitive to the presence of a magneticﬁeld,different conditions have been examined,allowing both the strength and the frequency of such aﬁeld to span relatively wide ranges and assuming different concentrations of nanoparticles.According to theﬁndings,the addition of nanoparticles to theﬂuid causes its rotation speed to increase by a factor of two,whereas ultraviolet radiation plays a negligible role.The amount of time required to attain the maximum rotation speed of the nanoﬂuid and the Nusselt number have been measured under both constant and alternating magneticﬁelds for a ferroﬂuid with a concentration of 0.5%and atﬂow Reynolds number of 550 and 1750.

关键词： Nano fluid rectengular tube magnetic field