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Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(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 *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** 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-x)O_(4) ferrites,where x=0.00,0.06,and *** 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 *** Xrd patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** 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 *** FTIr analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEm images,and it is increased from 121 to 198 *** 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-x)O_(4) ***,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 *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** 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

Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： V.A.KrUPIN m.r.NUrGALIEV A.r.NEmETS I.A.ZEmTSOV S.d.SUNTSOV T.B.mYALTON d.S.SErGEEV N.A.SOLOVEV d.V.SArYCHEV d.V.rYJAKOV S.N.TUGArINOV N.N.NAUmENKO National research Centre“Kurchatov Institute” Moscow 123182Russia Bauman moscow State Technical University Moscow 105005Russia Institution“Project Center ITEr” Moscow 123098Russia JSC“SOLAr” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECrH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECrH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECrH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECrH regimes. discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient r/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and r/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

radioisotope production using lasers:From basic science to applications

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matter and radiation at Extremes 2024年第3期9卷 31-44页

作者： m.r.d.rodrigues A.Bonasera m.Scisciò J.A.Pérez-Hernández m.Ehret F.Filippi P.L.Andreoli m.Huault H.Larreur d.Singappuli d.molloy d.raffestin m.Alonzo G.G.rapisarda d.Lattuada G.L.Guardo C.Verona Fe.Consoli G.Petringa A.mcNamee m.La Cognata S.Palmerini T.Carriere m.Cipriani G.di Giorgio G.Cristofari r.de Angelis G.A.P.Cirrone d.margarone L.Giuffrida d.Batani P.Nicolai K.Batani r.Lera L.Volpe d.Giulietti S.Agarwal m.Krupka S.Singh Fa.Consoli Cyclotron Institute Texas A&M UniversityCollege StationTexas 77840USA Laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly ENEA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro de Láseres Pulsados(clpu) VillamayorSpain Universidad de Salamanca SalamancaSpain Centre Lasers Intenses et Applications(CELIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Holdings Pty FreshwaterNew South WalesAustralia School of mathematics and Physics Queen’s University BelfastBelfastUnited Kingdom dipartimento di Fisica e Astronomia“E.majorana ”Università di CataniaCataniaItaly Facoltàdi Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly dipartimento di Ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly dipartimento di Fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto Nazionale di Fisica Nucleare Sezione di PerugiaPerugiaItaly ELI Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETSIA Universidad Politécnica de MadridMadridSpain dipartimento Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of Czech Academy of Sciences PragueCzech Republic Institute of Plasma Physics of Czech Academy of Sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few *** with energies of tens of meV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary *** such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical *** use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on *** this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other *** the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy *** experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,*** distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium *** results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[*** ***.,Sect.A 637,164–170(2011)].

关键词： purity estimates backward

Aerodynamics of a Tandem-Bladed Axial Compressor rotor under Circumferential distortion at different rotational Speeds

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Journal of Thermal Science 2024年第4期33卷 1340-1356页

作者： Amit KUmAr Jerry T.JOHN A.m.PrAdEEP r.A.dAKKErmANS dragan KOZULOVIC department of Aerospace Engineering Indian Institute of Technology BombayMumbai400076India department of Automotive and Aeronautical Engineering Hamburg University of Applied Sciences20099HamburgGermany Institute of Jet Propulsion Bundeswehr University Munich85577NeubibergGermany

For most aircraft engines,inflow distortion is *** distortion is known to degrade the aerodynamic performance and stable operating limits of a *** rotor configuration is an arrangement that effectively controls the growth of the boundary layer over the suction surface of the ***,a higher total pressure rise can be achieved through this unconventional design approach involving the splitting of the blade into forward and aft *** is expected that the effect of inlet flow distortion would be more severe for a tandem-rotor design due to the greater flow turning inherent in such ***,this aspect needs to be thoroughly *** present study discusses the effect of circumferential distortion on the tandem-rotor at different rotational ***-annulus rANS simulations using ANSYS CFX are used in the present *** performance of the rotor at a particular flow coefficient and different rotational speeds is *** total pressure and efficiency are observed to drop at lower mass flow rates under the influence of circumferential *** loss region in each blade passage is mainly associated with the blade wake,tip leakage vortex,secondary flow,and boundary ***,their contribution varies from passage to passage,particularly in the distorted *** the lower span,the wake width is found to be higher than that at a higher *** to the redistribution of the mass flow,the circumferential extent reduces at a higher *** the undistorted sector,the strength of the tip leakage vortex is significantly higher at the design rotational speed than at lower *** distortion near the tip region promotes an early vortex breakdown even at the design operating *** adversely affects the total pressure,efficiency,and stall *** clean flow conditions,this phenomenon is only observed near the stall *** the design operating condition,the breakdown of the forward rotor tip l

关键词： tandem rotor circumferential distortion loss tip leakage vortex vortex breakdown diffusion factor aerodynamics of compressor blade

Viscoelastic potential flow instability theory of rivlin-Ericksen electrified fluids of cylindrical interface

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Journal of Ocean Engineering and Science 2024年第4期9卷 311-316页

作者： d.m.mostafa department of mathematics College of ScienceQassim UniversityPO Box 6644Buraidah 51452Saudi Arabia department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

A linear electrohydrodynamic Kelvin-Helmholtz instability of the interface between two viscoelastic rivlin-Ericksen fluids enclosed by two concentric horizontal cylinders has been studied via the viscoelastic potential flow *** dispersion equation of complex coefficients for asymmetric disturbance has been obtained by using normal mode *** stability criteria are analyzed theoretically and illustrated *** imaginary part of growth rate is plotted versus the wave *** influences of dynamic viscoelastic,uniform velocities,reynolds number,electric field,dynamic viscosity,density fluids ratio,dielectric constant ratio and inner fluid fraction on the stability of the system are *** study finds its significance in Ocean pipelines to transfer oil or gas such as Eastern Siberia-Pacific Ocean oil pipeline.

关键词： rivlin-Ericksen fluid Cylindrical flow Viscoelastic potential flow Electrohydrodynamics stability

Structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano materials Science 2024年第4期6卷 475-483页

作者： A.d.Veloso A.m.Ferraria A.m.Botelho do rego A.S.Viana A.J.S.Fernandes A.J.Fielding r.A.Videira m.C.Oliveira CQ-Vr and Chemistry department University of Trás-os-Montes e Alto Douro BSIrG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa Centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics department University of AveiroCampus de Santiago Faculty of Science Pharmacy and Biomolecular SchoolLiverpool John Moores University rEQUImTE/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （m）.In parallel,alcohol and ether （epoxide） surface groups evolve into more oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPr） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon Surface functionalization Nmr XPS Hydrophilic carbon Paramagnetic

Assessing the biennial conference on science and technology(BICOST IX)2023 technical output on renewable energy,energy storage,and green hydrogen in line with UN SdG commitments

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Clean Energy 2024年第2期8卷 85-88页

作者： S.K.B.d.Silva K.G.d.Piyumali rasitha Thilini Suranjana Perera K.d.K.G.Kaluarachchi Thilini munagamage r.m.r.Ahammed C.S.P.Piyankarage Seyed Shahmy Veranja Karunaratne National Science and Technology Commission of Sri Lanka ColomboSri Lanka Sri Lanka Technological Campus(SLTC) PadukkaSri Lanka University of Peradeniya PeradeniyaSri Lanka

The development,production and utilization of renewable energy,energy storage and green hydrogen and the associated technologies in Sri Lanka have great potential to contribute to the United Nations’Sustainable development Goals(SdGs).The island aims to achieve 70%electricity generation from renewable energy sources by 2030(within the target of 40%utilization of renewable energy sources for the entire energy generation of the country by 2030).The power sector has to invest US$11 billion from 2023 to 2030 to contribute to reaching this *** commentary aims to provide a critical perspective on the recommendations of the report from the National Science and Technology Commission’s 9th biennial conference in 2023 on science and technology,the sub-thematic technical report on clean energy,energy storage and green hydrogen in line with the SdGs in the Sri Lankan *** technical report provides insightful recommendations for Sri Lanka’s energy sector under three main sections:renewable energy,energy storage and green ***,it explores the potential of various renewable energy sources,energy storage systems and green hydrogen as sustainable solutions to address the country’s energy challenges while emphasizing the spillover effects of them,which could contribute to the enterprise’s job creation and uplift the economy.

关键词： renewable energy energy storage green hydrogen sustainable development goals Sri Lanka social economic environmental sustainable affordable

Excellent photoluminescence and electrochemical properties of Sm^(3+) doped Ca_(2)mgSi_(2)O_(7) nanophosphor:display and electrochemical sensor applications

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Journal of rare Earths 2024年第6期42卷 1046-1055,I0002页

作者： r.B.Basavaraj K.Sureshkumar d.P.Aarti m.B.madhusudana reddy G.Nagaraju T.ramakrishnappa G.r.Navyashree K.r.Venkatesha Babu K.S.Hemalatha department of Physics BMS Institute of Technology and ManagementBangalore560064India department of Chemistry BMS Institute of Technology and ManagementBangalore560064India department of Chemistry School of Applied SciencesREVA UniversityBangalore560064India Energy materials researchLaboratory Department of ChemistrySiddaganga Institute of TechnologyTumakuru57203KarnatakaIndia School of Physical Sciences REVA UniversityBangalore560057Indi department of Physics Govt.Science CollegeBengaluru560001India department of Physics Maharani Science College for WomenMaharani Cluster UniversityBengaluru560001India

A series of orange-red light emitting Ca_(2)mgSi_(2)O_(7):Sm^(3+)nanopowders were fabricated via low-cost ecofriendly green combustion technique using Aloe vera gel as *** phase purity of the samples were confirmed by the powder X-ray diffraction(PXrd)*** single-phase tetragonal structure is observed from the PXrd results with no additional impurity *** band gap energy of the fabricated powders was estimated by diffuse reflectance spectra(drS)and is found to be in the range of 4.01-5.98 eV.A high resolution scanning electron microscope(SEm)was used to study the morphological behaviour of the ***-like structures are observed from the SEm *** particle size was evaluated by transmission electron microscopy(TEm)and is found to be~50 *** interplanar distance is found to be 0.53 *** properties were systematically studied in *** phosphors are successfully excited at 403 nm NUV light,producing reddish-orange characteristic *** emission peaks are centered at 558(^(4)G_(5/2)→^(6)H_(5/2)),607(^(4)G_(5/2)→^(6)H_(7/2))and 645 nm(^(4)G_(5/2)→^(6)H_(9/2)),*** the observed peaks the red emanation(^(4)G_(5/2)→^(6)H_(7/2))is stronger than the orange emission(^(4)G_(5/2)→^(6)H_(5/2))in the current *** photoluminescent concentration quenching is noticed above 5 mol%Sm^(3+)ion doping *** dipole-dipole interaction resulting in cross relaxation is found to be the principal cause of concentration quenching *** color features such as Commission Internationale de I’Eclairage(CIE)and correlated color temperature(CCT)were studied in *** optimized chromaticity coordinates were estimated to be(0.6363,0.3632),which fall in the reddish-orange *** average CCT value obtained is 3362 *** average color purity is found to be~82%.Sm^(3+)incorporated Ca_(2)mgSi_(2)O_(7) samples are possible contender for single white light generation commercial candidates owing to

关键词： Green combustion Photoluminescence Orange-red emission Color purity Sensors rare earths

Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-rodríguez m.Gutiérrez-roa C.Giménez-rubio d.ríos-ruiz P.Arévalo-Cid m.V.martínez-Huerta A.Zitolo m.J.Lázaro d.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)rr) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)rr. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(rrdE), technique still rarely explored for CO_(2)rr. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 m KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. rHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. rHE with a H_(2)/CO ratio of 1.8. These results demonstrate that rrdE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)rr.

关键词： Cu-N-C Carbon xerogel rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide