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BaTiO_(3)solid solutions co-doped with Gd^(3+)and Eu^(3+):Synthesis,structural evolution and dielectric properties

Journal of Rare Earths 2024年第10期42卷 1920-1926页

作者： R.martínez-López m.pérez-Labra J.A.Romero-Serrano F.R.Barrientos-Hernández m.Reyes-pérez m.i.Valenzuela-Carrillo G.Urbano-Reyes V.E.Reyes-Cruz G.i.dávila-pulido Academic Area of Earth Sciences and materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico metallurgy and materials department ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

in this paper,the synthesis,structural evolution,and dielectric properties of BaTiO_(3)solid solutions codoped with rare earth elements(Gd^(3+)and Eu^(3+))prepared using the solid-state reaction method are *** pure precursor powders of BaCl_3,TiO_(2),Gd_(2)O_(3),and Eu_(2)O_(3)were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 mpa and sintered at 1300℃in air atmosphere for 6 h to obtain Ba_(1-3x)Gd_(2x)Ti_(1-3x)Eu_(4x)O_(3)(x=0,0.0015,0.01 and0.1).X-ray diffraction(XRd)and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO_(3)for the samples with x=0,0.0015 and 0.01,as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd^(3+)and Eu^(3+)in the BaTiO_(3)structure is reached for the sample with x>0.01,and the orthorhombic Eu_2TiO_(5)and monoclinic BaTi_(2)O_(5)secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO_(3)around 716 cm^(-1)(LO of A1 symmetry),515 cm^(-1)(TO of A1 symmetry),and 305 cm^(-1)(B1).The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the BaTiO_(3)*** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO_(3) doping Gadolinium Europium Synthesis Rare earths

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Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese physics B 2024年第2期33卷 108-114页

作者： U.S.mahabaleshwar G.p.Vanitha L.m.pérez Emad H.Aly i.pop department of Studies in mathematics Davangere UniversityShivagangothriDavangereIndia departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt department of mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

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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

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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

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Frontier of the paleo-Tethys Ocean in the western mediterranean:isotopic(Sm-Nd)constraints on sources of devonian units from menorca island

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Geoscience Frontiers 2024年第5期15卷 323-338页

作者： Ricardo Arenas Jose m.Fuenlabrada Cristian Timoner Rubén díez Fernández Esther Rojo-pérez departamento de mineralogía y petrología and instituto de Geociencias(UCm CSIC)Universidad ComplutenseMadridSpain Unidad de Geocronología(CAi de Ciencias de la Tierra y Arqueometría) Universidad ComplutenseMadridSpain Bayerisches Geoinstitut University of BayreuthBayreuthGermany instituto Geológico y minero de España–CSiC SalamancaSpain

The c.1000-m-thick pre-orogenic devonian mainly metapelitic sequence of North menorca island shows a fairly complete stratigraphic *** rocks of this sequence indicate gradually increasing deeper marine conditions of sedimentation towards its uppermost ***,the obtained sedimentary characteristics resemble those related to a deep and narrow basin-associated *** sills of Ti-augite-bearing alkaline gabbros occur within the devonian *** intensity of Variscan deformation increases downwards through the *** to the characteristics of the devonian sequence and its location within the Variscan Orogen,a correlation with similar units located in the southern sectors of the Central iberian Zone(iberian massif)is *** devonian metapelitic rocks have geochemical characteristics suggesting that they represent moderately recycled mature siliciclastic sediments,generated from erosion of distant source areas belonging to an upper continental *** relatively narrow range of variation observed in initial^(143)Nd/^(144)Nd ratios supports a similar source for the menorcan slates(0.51165–0.51182).However,a marked trend is observed in these isotope ratios,from lower values at the base of the stratigraphic column(minimum value of 0.511941)to higher values at the top(maximum value of 0.512131).The^(147)Sm/^(144)Nd ratios vary between 0.1074 and 0.1238,within the range defined for siliciclastic rocks with felsic crustal *** Nd model ages define a narrow range between 1496 ma and 1754 ma(Late paleoproterozoic–Early mesoproterozoic),and they are consistently younger *** data rule out a provenance from the erosion of the West Africa Craton,as they are more compatible with a provenance from regions located in the Trans-Saharan Belt or Sahara *** characteristics of the menorcan devonian sequence are compatible with its deposition in a narrow and deep peri-Gondwanan transtensional basin,gener

关键词： Western paleo-Tethys frontiers menorca island Sm-Nd isotopic constraints devonian sequence provenance in Gondwana

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Coffee Leaf Rust(Hemileia vastatrix)disease in Coffee plants and perspectives by the disease Control

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phyton-international Journal of Experimental Botany 2024年第5期93卷 923-949页

作者： Alexis Salazar-Navarro Victor Ruiz-Valdiviezo Jose Joya-dávila daniel Gonzalez-mendoza instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(iCA-UABC) Nuevo LeónBaja California21705México Laboratorio de Biología molecular del instituto Tecnológico Nacional de Tuxtla Gutierrez(TecNm) Tuxtla GutierrezChiapas29050México Facultad de Ciencias Agronómicas Campus V.Universidad Autónoma de Chiapas(UNACH) VillafloresChiapas30470México

Coffee Leaf Rust(CLR)is caused by Hemileia vastatrix in Coffea *** is one of the most dangerous phytopathogens for coffee plantations in terms of coffee productivity and coffee cup *** this review,we resume the problem of CLR in mexico and the pathogenesis of *** review abord plant-pathogen interactions which lead a compatible or incompatible interactions and result in CLR disease or resistance,*** review abord Coffea *** response pathways involved in *** ***,current measures to control *** proliferation and germination were aborded focused on phytosanitary actions,and biological and chemical ***,new trendlines to reduce the impact of CLR as nanoparticles and nanotechnology were analyzed.

关键词： Coffee leaf rust Coffea arabica pathogenesis nanoparticles biological control

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metabolomics for the diagnosis of bladder cancer: A systematic review

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Asian Journal of Urology 2024年第2期11卷 221-241页

作者： Herney Andrés García-perdomo Angélica maría dávila-Raigoza Fernando Korkes division of Urology/Urooncology Department of SurgerySchool of MedicineUniversidad del ValleCaliColombia UROGiV Research Group School of MedicineUniversidad del ValleCaliColombia Urologic Oncology Division of UrologyABC Medical SchoolSao PauloBrazil

Objective: metabolomics has been extensively utilized in bladder cancer (BCa) research, employing mass spectrometry and nuclear magnetic resonance spectroscopy to compare various variables (tissues, serum, blood, and urine). This study aimed to identify potential biomarkers for early BCa ***: A search strategy was designed to identify clinical trials, descriptive and analytical observational studies from databases such as medline, Embase, Cochrane Central Register of Controlled Trials, and Latin American and Caribbean Literature in Health Sciences. inclusion criteria comprised studies involving BCa tissue, serum, blood, or urine profiling using widely adopted metabolomics techniques like mass spectrometry and nuclear magnetic resonance. primary outcomes included description of metabolites and metabolomics profiling in BCa patients and the association of metabolites and metabolomics profiling with BCa diagnosis compared to control patients. The risk of bias was assessed using the Quality Assessment of Studies of diagnostic ***: The search strategy yielded 2832 studies, of which 30 case-control studies were included. Urine was predominantly used as the primary sample for metabolite identification. Risk of bias was often unclear inpatient selection, blinding of the index test, and reference standard assessment, but no applicability concerns were observed. metabolites and metabolomics profiles associated with BCa diagnosis were identified in glucose, amino acids, nucleotides, lipids, and aldehydes ***: The identified metabolites in urine included citric acid, valine, tryptophan, taurine, aspartic acid, uridine, ribose, phosphocholine, and carnitine. Tissue samples exhibited elevated levels of lactic acid, amino acids, and lipids. Consistent findings across tissue, urine, and serum samples revealed downregulation of citric acid and upregulation of lactic acid, valine, tryptophan, taurine, glutamine, aspartic acid, uridine, rib

关键词： metabolite metabolomics Bladder cancer metabolomicsprofile

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Solution of the Center problem for a Class of polynomial differential Systems

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Acta mathematica Sinica,English Series 2024年第7期40卷 1685-1696页

作者： Chang Jian Liu Jaume Llibre Rafael Ramírez Valentín Ramírez School of mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai519086P.R.China departament de matemàtiques Universitat Autònoma de Barcelona08193BellaterraBarcelonaCataloniaSpain departament d’Enginyeria informàtica i matemàtiques Universitat Rovira i VirgiliAvinguda dels Paiïsos Catalans 2643007TarragonaCataloniaSpain

Consider the polynomial differential system of degree m of the form x=-y(1+μ(a_(2)x-a_(1)y))+x(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),y=x(1+μ(a_(2)x-a_(1)y))+y(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),whereμandνare real numbers such that(μ^(2)+v^(2))(μ+v(m-2))(a_(1)^(2)+a_(2)^(2))≠m>2 andΩ_(m−1)(x,y)is a homogenous polynomial of degree m−1.A conjecture,stated in *** Equations 2019,suggests that whenν=1,this differential system has a weak center at the origin if and only if after a convenient linear change of variable(x,y)→(X,Y)the system is invariant under the transformation(X,Y,t)→(−X,Y,−t).For every degree m we prove the extension of this conjecture to any value ofνexcept for a finite set of values ofμ.

关键词： Center problem polynomial differential system

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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

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A comprehensive look at the psychoneuroimmunoendocrinology of spinal cord injury and its progression: mechanisms and clinical opportunities

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military medical Research 2024年第2期11卷 228-267页

作者： miguel A.Ortega Oscar Fraile-martinez Cielo García-montero Sergio Haro miguel Ángel Álvarez-mon diego de Leon-Oliva Ana m.Gomez-Lahoz Jorge monserrat mar Atienza-pérez david díaz Elisa Lopez-dolado melchor Álvarez-mon department of medicine and medical Specialities University of Alcala28801 Alcala de HenaresSpain Ramón y Cajal institute of Sanitary Research(iRYCiS) 28034 MadridSpain department of psychiatry and mental Health Hospital Universitario Infanta Leonor28031 MadridSpain Service of Rehabilitation National Hospital for Paraplegic PatientsCarr.de la PeraledaS/N45004 ToledoSpain immune System diseases‑Rheumatology Service and internal medicine University Hospital Príncipe de Asturias(CIBEREHD)28806 Alcala de HenaresSpain

Spinal cord injury(SCi)is a devastating and disabling medical condition generally caused by a traumatic event(primary injury).This initial trauma is accompanied by a set of biological mechanisms directed to ameliorate neural damage but also exacerbate initial damage(secondary injury).The alterations that occur in the spinal cord have not only local but also systemic consequences and virtually all organs and tissues of the body incur important changes after SCi,explaining the progression and detrimental consequences related to this ***(pNiE)is a growing area of research aiming to integrate and explore the interactions among the different systems that compose the human organism,considering the mind and the body as a *** initial traumatic event and the consequent neurological disruption trigger immune,endocrine,and multisystem dysfunction,which in turn affect the patient's psyche and *** the present review,we will explore the most important local and systemic consequences of SCi from a pNiE perspective,defining the changes occurring in each system and how all these mechanisms are ***,potential clinical approaches derived from this knowledge will also be collectively presented with the aim to develop integrative therapies to maximize the clinical management of these patients.

关键词： Spinal cord injury(SCi) psychoneuroimmunoendocrinology(pNiE) Secondary injury immunoinflammatory dysfunction Gut microbiota Translational opportunities

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