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multiple scales method for analyzing a forced damped rotational pendulum oscillatorwithgallows

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Communications in Theoretical Physics 2024年第5期76卷 58-67页

作者： Haifa A Alyousef Alvaro H salas B m Alotaibi s A El-Tantawy Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of mathematics and statistics Universidad Nacional de ColombiaFIZMAKO Research GroupColombia Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversityAl-Baha 1988Saudi Arabia

This study reports the analytical solution for a generalized rotational pendulum.s.stem with gallows and periodic excited *** multiple scales method(msm)is applied to solve the proposed *** types of rotational pendulum oscillators are studied and talked about in *** include the forced damped rotating pendulum oscillator with gallows,the damped standard simple pendulum oscillator,and the damped rotating pendulum oscillator without *** msm first-order approximations for all the cases mentioned are derived in *** obtained results are illustrated with concrete numerical *** first-order msm approximations are compared to the fourth-order Runge-Kutta(RK4)numerical ***,the maximum error is estimated for the first-order approximations obtained through the msm,compared to the numerical approximations obtained by the RK4 ***,we conducted a comparative analysis of the outcom.s.obtained by the used method(msm)and He-msm to ascertain their respective levels of *** proposed method can be applied to analyze many strong nonlinear oscillatory equations.

关键词： rotational pendulum.s.stem multiple scales method approximate solution damped oscillations forced pendulum with gallows he-multiple scales method

Acceleration of solar wind particles due to inertial Alfvén waves

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Communications in Theoretical Physics 2024年第6期76卷 137-141页

作者： Kiran Batool Imran A Khan m.s.amir Abdul Kabir s Ayaz Theoretical Physics Department National Centre for PhysicsIslamabad 44000Pakistan Department of space sciences Institute of Space TechnologyIslamabad 44000Pakistan space and Astrophysics Research Lab(sARL) National Center of GIS and Space Applications(NCGSA)Islamabad 44000Pakistan salam Chair Department of PhysicsGC University LahoreKatchery RoadLahorePunjab 54000Pakistan Department of space science and CsPAR University of Alabama in HuntsvilleHuntsvilleAL 35899United States of America

Gaining an understanding of the effects and dynamics of the solar wind is crucial for the study of space weather,Earth's magnetosphere,spacecraft protection,the dynamics of the solar system,and various other *** show that Alfvén waves effectively transfer energy to resonant *** study demonstrates how inertial Alfvén waves deliver their energy to resonant plasma particles in different solar environments under certain *** analysis shows that inertial Alfvén waves experience more rapid damping with increasing parallel wavenumber,ambient magnetic field strength,and particle number density,coupled with a decrease in *** rate of energy transfer to resonant particles intensifies with higher temperatures and reduced parallel wavenumber and particle number *** with higher initial velocities actively participate in Landau damping,especially in regions with a stronger ambient magnetic field.

关键词： solar wind inertial Alfven waves resonant particles

Twinning aspects and their efficient roles in wrought mg alloys:A comprehensive review

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Journal of magnesium and Alloys 2024年第6期12卷 2201-2230页

作者： s.s.A.shah manping Liu Azim Khan Farooq Ahmad m.R.Abdullah Xingquan Zhang shiwei Xu Zhen Peng school of materials science and Engineering Jiangsu UniversityZhenjiang 212013China school of mechanical Engineering Anhui University of TechnologyMáanshan 243002China College of mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China

Twinning is widely recognized as an effective and cost-efficient method for controlling the microstructure and properties of wrought magnesium(mg)***,twins play a crucial role in initiating dynamic recrystallization(DRX),while twin regions experience rapid recrystallization during static recrystallization(sRX).The activation of twinning can lead to changes in lattice orientation,significantly impacting the final texture in mg *** active roles of twinning are influenced by various factors during the activation process,and the mobility of twin boundaries(TB)can be amplified by stress effects,dislocation interactions,and thermal ***,annealing treatments that involve proper segregation or precipitation on TBs serve to stabilize them,restraining their *** such as segregation may also alter the twinning propensity in magnesium-rare earth(mg-RE)***{10-11}contraction twins(CT)and{10-11}-{10-12}double twins(DT)can promote dynamic recrystallization(DRX),they also pose a risk as potential sources of voids and ***,understanding the nucleation and growth mechanisms of twinning is crucial,and these aspects are briefly reviewed in this *** the factors mentioned above,this article summarizes the recent research progress in this field,shedding light on advancements in recent eras.©2024 Chongqing *** services provided by Elsevier *** behalf of KeAi Communications ***.

关键词： mg alloys Twinning Recrystallization Texture mechanical properties

An Integral method for solving Dynamic Equations with Fluid–solid Coupling

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Acta mechanica solida sinica 2024年第1期37卷 99-108页

作者： Xin Zhang Jie Liu Pu Xue shuowen Yan Yahao Xu m.s.Zahran school of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China school of mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Civil Engineering Military Technical CollegeCairo 11435Egypt

In this work,a new methodology is presented to mainly solve the fluid–solid interaction(FsI)*** methodology combines the advantages of the Newmark precise integral method(NPIm)and the dual neural network(DNN)*** NPIm is employed to modify the exponential matrix and loading vector based on the DNN integral *** involves incorporating the basic assumption of the Newmark-βmethod into the dynamic equation and eliminating the acceleration term from the dynamic equilibrium *** a result,the equation is reduced to a first-order linear equation ***,the PIm is applied to integrate the system.s.ep by step within the *** DNN method is adopted to solve the inhomogeneous term through fitting the integrand and the original function with a pair of neural networks,and the integral term is solved using the Newton–Leibniz *** examples demonstrate that the proposed methodology significantly improves computing efficiency and provides sufficient precision compared to the DNN *** is particularly evident when analyzing large-scale structures under blast loading conditions.

关键词： Newmark precise integral method(NPIm) Dual neural networks(DNN) Fluid-solid interaction(FsI) Dynamic time-history analysis Blast loading

Tuning structural,electrical,dielectric and magnetic properties of mg-Cu-Co ferrites via dysprosium(Dy^(3+))doping

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Journal of Rare Earths 2024年第1期42卷 137-146,I0005页

作者： maria Akhtar m.s.Hasan Nasir Amin N.A.morley muhammad Imran Arshad Department of Physics Government College UniversityFaisalabad38000Pakistan Department of Physics The University of Lahore53700Pakistan Department of materials science and Engineering The University of SheffieldS13JDUK Department of Physics&Astronomy University College LondonUK

In current research work,Dy3+substituted mg0.5Cu0.25Co0.25Fe2-xDyxO4(0.0≤x≤0.04 with the step interval of 0.01)soft ferrites were synthesized by the sol-gel auto combustion *** prepared samples were characterized by the techniques using X-ray diffraction(XRD),scanning electron microscopy(sEm),energy dispersive X-ray spectroscopy(EDs),Fourier transform infrared(FTIR)spectroscopy,curre nt-voltage(Ⅰ-Ⅴ)measurement,LCR meter,vibrating sample magnetometer(Vsm)and *** data reveal that the average crystallite size is 49.71 nm and the lattice constant is 0.83703 nm for sample x=*** non-uniform grain growth was demonstrated by micrographs and impurity-free elemental composition was observed from EDX *** DC resistivity has an increasing and decreasing trend in ferromagnetic and paramagnetic regions with an increase in ***,the high resistivity is observed with the order of 1010Ω·cm,and the activation energy is 0.944 eV for samples x=*** dielectric parameters including dielectric constant,dielectric losses,and impedance gradually decrease with the increase in frequency from 8 Hz to 8 *** minimum dielectric loss at high frequency is found for sample x=*** coercivity(Hc)and saturation magnetization(ms)are found in the ranges of 520.82-544.02 Oe and 20.5841-21.1473 emu/g,*** observations confirm that dysprosium(x=0.03)doped mCC-soft ferrites may be applicable in transformer cores,microwave absorbance,and telecommunication devices.

关键词： soft ferrites DC resistivity Dielectric loss Impedance Coercivity Rare earths

Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)snO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： m.K.h.Hamad Nidal Dwaikat m.H.A.mhareb m.I.sayyed R.m.Hamad Y.s.m.Alajerami m.A.Alm.s.iere Gameel saleh Ahmad Hussein Alomari K.A.Ziq Department of Basic sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&minerals Regulatory Comm.s.ion Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)snO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOm computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)snO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding m.s. stopping power Rare earths

Astrophysical s-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model

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Chinese Physics C 2024年第4期48卷 130-145页

作者： s.B.Dubovichenko A.s.Tkachenko R.Ya.Kezerashvili N.A.Burkova B.m.Yeleusheva Fesenkov Astrophysical Institute 050020 AlmatyKazakhstan New York City College of Technology City University of New YorkBrooklyn11201 New YorkUSA Graduate school and University Center City University of New York10016 New YorkUSA al-Farabi Kazakh National University 050040 AlmatyKazakhstan

We study radiative p^(15)N capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(mPCm)with forbidden states,including low-lying *** investigation of the ^(15)N(p,γ0)^(16)O reaction includes the consideration of ^(3)s_(1) resonances due to E1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)N channel due to the ^(3)P_(1)→^(3)P_(0)m1 *** calculated the astrophysical low-energy s-factor,and the extrapolated s(0)turned out to be within 34.7−40.4 keV·*** important role of the asymptotic constant(AC)for the ^(15)N(p,γ0)16O process with interfering ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances is elucidated.A comparison of our calculation for the s-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is *** reaction rate is calculated and compared with the existing *** has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances in reference to the CNO Gamow windows,especially at low *** estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from ***.C.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=*** present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)N(p,γ)^(13)O,^(13)N(p,γ)^(14)O,^(14)N(p,γ)^(15)O,and ^(15)N(p,γ)^(16)O obtained in the framework of the mPCm and provide the temperature windows,prevalence,and significance of each process.

关键词： low and astrophysical energies p^(15)N system thermonuclear reaction rate potential cluster model CNO-cycle

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.s.mple 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

Provenance and depositional setting of the Late miocenePleistocene clastic sediments in the eastern Arabian Peninsula and western Iraq using rare earth elements geochem.s.ry

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Acta Geochimica 2024年第2期43卷 399-410页

作者： salih m.Awadh Zinah s.Al-Ankaz mohanad R.A.Al-Owaidi John s.Armstrong-Altrin Department of Geology College of ScienceUniversity of BaghdadBaghdadIraq Department of Geology College of ScienceUniversity of WasitWasit 52011Iraq Department of Applied Geology College of ScienceUniversity of BabylonBabylon 51001Iraq Unidad de Procesos Oceanicos y Costeros Instituto de Ciencias del Mar y LimnologíaUniversidad Nacional Autonoma de MexicoCiudad Universitaria04510 Mexico CityCDMXMexico Department of marine sciences Bharathidasan UniversityTiruchirapalliTamil Nadu 620024India

The sandstones of the Late miocene–Pliocene Dibdibba Formation in the Najaf–Karbala Plateau and Basra were examined to determine their source rocks and origin. The rare earth elements(REE) and trace elements(sc, Co, V, and Th) concentrations in these sandstones revealed that they likely derived from a single source. The steep light rare earth elements(LREE) and flat, heavy rare earth element(HREE) patterns, negative Eu anomaly, and high ΣREE contents in sandstones suggest its derivation from a suggests that a passive continental margin environment and originated from felsic source rocks. The average concentration of ΣREE is 93.5 ppm, which is lower than that of the average crustal compositions like Upper Continental Crust and Post Archean Australian shale. The higher proportion of LREE compared to HREE implies that these sandstones were recycled and derived from a distal source. The Th/Co, Th/sc, La/sc, La/Co, Eu/Eu*and(La/Lu)cn elemental ratios indicated that these Late miocene–Pliocene sandstones were derived from felsic rocks located in the marginal region of the Arabian shield.

关键词： REE Dibdibba formation Clastic sediments Passive continental margin