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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 method.The 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 Raman.XRD data reveal that the average crystallite size is 49.71 nm and the lattice constant is 0.83703 nm for sample x=0.03.The non-uniform grain growth was demonstrated by micrographs and impurity-free elemental composition was observed from EDX analysis.The DC resistivity has an increasing and decreasing trend in ferromagnetic and paramagnetic regions with an increase in temperature.moreover,the high resistivity is observed with the order of 1010Ω·cm,and the activation energy is 0.944 eV for samples x=0.03.The dielectric parameters including dielectric constant,dielectric losses,and impedance gradually decrease with the increase in frequency from 8 Hz to 8 mHz.The minimum dielectric loss at high frequency is found for sample x=0.03.The coercivity(Hc)and saturation magnetization(ms)are found in the ranges of 520.82-544.02 Oe and 20.5841-21.1473 emu/g,respectively.These 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.Almessiere 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 Commission 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 method.The prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis spectroscopy.The shielding properties against ionizing radiation were also investigated.The XRD analysis shows the perovskite cubic structure as the major phase in all samples.The FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-sn-O vibration.UV-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 samples.Gamma-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOm computational results.The relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%range.The addition of Er leads to the enhanced density,neutron,and gamma shielding features.In contrast,charged particles’shielding parameters gradually reduce with rising Er contents.These 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 mass 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 resonances.The 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 transition.We calculated the astrophysical low-energy s-factor,and the extrapolated s(0)turned out to be within 34.7−40.4 keV·b.The 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 found.The reaction rate is calculated and compared with the existing rates.It 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 temperatures.We estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from Phys.Rev.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)=1.3.We 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 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

Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

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Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： m.Grandin H.K.Connor s.Hoilijoki m.Battarbee Y.Pfau-Kempf U.Ganse K.Papadakis m.Palmroth Department of Physics University of HelsinkiHelsinkiFinland NAsA Goddard space Flight Center GreenbeltMD20771USA space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing techniques.The solar wind magnetosphere Ionosphere Link Explorer(smILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their soft X-ray Imager(sXI)instruments.While earlier modeling works have already simulated soft X-ray images as might be obtained by smILE sXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space plasma.To investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator model.The simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic field.We first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial views.We then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the magnetopause.Our results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the smILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray images.For instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this region.Likewise,a proton density increase by 14%in the magnetosheath associated with mirror-mode structures can resu

关键词： magnetosphere magnetosheath numerical simulation smILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

search for production of dark fermion candidates in association with heavy neutral gauge boson decaying to dimuon in proton-proton collisions at√s=8 TeV using Cms open data

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Chinese Physics C 2024年第4期48卷 6-13页

作者： Y.mahmoud H.Abdallah m.T.Hussein s.Elgammal Centre for theoretical physics The British University in EgyptEgypt Physics Department Faculty of ScienceCairo UniversityEgypt

In this study,we conducted a search for dark matter using a part of the data recorded by the Cms experiment during run-I of the LHC in 2012 with a center of mass energy of 8 TeV and an integrated luminosity of 11.6 fb−1.These data were gathered from the Cms open data.Dark matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.Thus,the search was conducted in the dimuon plus large missing transverse momentum channel.One benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the Cms open data.No evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.

关键词： dark matter large hadron collider Cms open data search for new physics dark fermion

A review on transition metal oxides based photocatalysts for degradation of synthetic organic pollutants

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Journal of Environmental sciences 2024年第5期139卷 389-417页

作者： Athira Krishnan Anna swarnalal Divine Das midhina Krishnan Viswanathan s.saji smAshibli Department of Chemistry Amrita Vishwa VidyapeethamAmritapuriKerala690525India Interdisciplinary Research Center for Advanced materials King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Chemistry University of KeralaKariavattom CampusThiruvananthapuramKerala695581India

This review provides insight into the current research trend in transition metal oxides(TmOs)-based photocatalysis in removing the organic colouring matters from water.For easy understanding,the research progress has been presented in four generations according to the catalyst composition and mode of application,viz:single component TmOs(the firstgeneration),doped TmOs/binary TmOs/doped binary TmOs(the second-generation),inactive/active support-immobilized TmOs(the third-generation),and ternary/quaternary compositions(the fourth-generation).The first two generations represent suspended catalysts,the third generation is supported catalysts,and the fourth generation can be suspended or supported.The review provides an elaborated comparison between suspended and supported catalysts,their general/specific requirements,key factors controlling degradation,and the methodologies for performance evaluation.All the plausible fundamental and advanced dye degradation mechanisms involved in each generation of catalysts were demonstrated.The existing challenges in TmOs-based photocatalysis and how the researchers approach the hitch to resolve it effectively are discussed.Future research trends are also presented.

关键词： Photocatalysis Dye degradation Transition metal oxides and composites supported catalysts suspended catalysts

Liquid biopsy for gastric cancer:Techniques,applications,and future directions

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World Journal of Gastroenterology 2024年第12期30卷 1680-1705页

作者： Cristina Díaz del Arco m Jesús Fernández Aceñero Luis Ortega medina Department of surgical Pathology Health Research Institute of the Hospital Clínico San CarlosHospital Clínico San CarlosMadrid 28040Spain Department of Legal medicine Psychiatry and PathologyUniversidad Complutense de MadridMadrid 28040Spain

After the study of circulating tumor cells in blood through liquid biopsy(LB),this technique has evolved to encompass the analysis of multiple materials originating from the tumor,such as nucleic acids,extracellular vesicles,tumor-educated platelets,and other metabolites.Additionally,research has extended to include the examination of samples other than blood or plasma,such as saliva,gastric juice,urine,or stool.LB techniques are diverse,intricate,and variable.They must be highly sensitive,and pre-analytical,patient,and tumor-related factors significantly influence the detection threshold,diagnostic method selection,and potential results.Consequently,the implementation of LB in clinical practice still faces several challenges.The potential applications of LB range from early cancer detection to guiding targeted therapy or immunotherapy in both early and advanced cancer cases,monitoring treatment response,early identification of relapses,or assessing patient risk.On the other hand,gastric cancer(GC)is a disease often diagnosed at advanced stages.Despite recent advances in molecular understanding,the currently available treatment options have not substantially improved the prognosis for many of these patients.The application of LB in GC could be highly valuable as a non-invasive method for early diagnosis and for enhancing the management and outcomes of these patients.In this comprehensive review,from a pathologist’s perspective,we provide an overview of the main options available in LB,delve into the fundamental principles of the most studied techniques,explore the potential utility of LB application in the context of GC,and address the obstacles that need to be overcome in the future to make this innovative technique a game-changer in cancer diagnosis and treatment within clinical practice.

关键词： Liquid biopsy Gastric cancer Circulating tumor cells Cell-free DNA Circulating tumor DNA molecular

magnesium oxide(mgO) nanoadsorbents in wastewater treatment: A comprehensive review

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Journal of magnesium and Alloys 2024年第5期12卷 1709-1773页

作者： H.C.s.Perera V.Gurunanthanan Anoop singh m.m.m.G.P.G.mantilaka G.Das sandeep Arya Department of Physics Khalifa University Postgraduate Institute of science University of Peradeniya Department of Humanities and sciences Guru Nanak Institutions Technical Campus Centre for Global Health Research Saveetha Medical College and Hospitals Saveetha Institute of Medical and Technical Sciences Department of Physics University of Jammu

Wastewater contamination by heavy metals and synthetic dyes presents a significant environmental challenge, necessitating effective and sustainable separation techniques. This review article provides a detailed examination of magnesium oxide(mgO) nanoparticles as an innovative nanoadsorbent for wastewater treatment, with a specific focus on heavy metal and dye removal. The review comprehensively explores various aspects of mgO nanoparticles, including their structural characteristics and synthesis techniques. The article delves into the morphology and crystallographic arrangement of mgO nanoparticles, offering insights into their structural attributes. Given the complexity of adsorption processes, the review identifies and analyzes parameters influencing the adsorption efficiency of mgO nanoparticles, such as temperature, pH, contact time, initial concentration, and co-existing ions. The interplay between these parameters and the adsorption capability of mgO nanoparticles emphasizes the importance of optimizing operational conditions. Furthermore, the review assesses various synthesis methods for mgO nanoparticles, including sol-gel, hydrothermal, precipitation, green synthesis, solvothermal, and template-assisted techniques. It discusses the advantages, limitations, and resulting nanoparticle characteristics of each method, enabling readers to grasp the implications of synthesis processes on adsorption efficiency. This comprehensive review consolidates current insights into the effectiveness of mgO nanoparticles as a potent nanoadsorbent for removing heavy metals and dyes from wastewater covering a wide spectrum of aspects related to mgO nanoparticles. moreover, there is a need to investigate the use of mgO in the treatment of actual wastewater or river water,in order to leverage its cost-effectiveness and high efficiency for practical water treatment applications in real-time.

关键词： mgO nanoparticles Nanoadsorbent Wastewater treatment Heavy metals Dye separation Adsorption synthesis methods