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Quenching Photolum.nescence of Eu(III) by Cu(II) in ZnO:Eu3++Cu2+ Com.ounds by Solution Com.ustion m.thod

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World j.urnal of Condensed m.tter Physics 2016年第3期6卷 269-275页

作者： S. López-Rom.ro m. j. quiroz jiménez m. García-Hipólito Departam.nto de m.teria Condensada y Criogenia Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de México Ciudad de México México

In this study Cu2++Eu3+ co-doped ZnO(ZnO/Cu2++Eu3+) solid solution powders were synthesized by solution com.ustion m.thod using as oxidant agent zinc nitrate hexahydrate and as fuel urea;the Cu2+ concentrations were 0, 1, 2, 3, 10, and 20 %Wt;the Eu3+ ion concentration was fixed in 3%Wt. The sam.les after were annealed at 900°C by 20 h in air. The structural results showed the largely presence of a wurtzite solid solution of Cu2++Eu3+doped ZnO, at high Cu2+ doping CuO and Eu2CuO4 phases are also present. m.rphological properties were analyzed using scanning electron m.croscopy (SEm. technique. However it is im.ortant to rem.rk that the Cu2+ ions suppress the Eu3+ ion photolum.nescence (PL) by m.ans of an overlap m.chanism.between Cu2+ absorption band and Eu3+em.ssion band (e.g. 5D0→7F2) of the Eu3+ em.ssion spectra.

关键词： ZnO Co-Doped Cu2++Eu3+ Quenching Photolum.nescence Solution Com.ustion

Structural and Optical Properties of Cu²⁺ + Ce³⁺ Co-Doped ZnO by Solution Com.ustion m.thod

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World j.urnal of Condensed m.tter Physics 2016年第4期6卷 300-309页

作者： S. López-Rom.ro m. j. quiroz jiménez m. García-Hipólito Departam.nto de m.teria Condensada y Criogenia Instituto de Investigaciones en Materiales Departamento de Materia Condensada y Criogenia Universidad Nacional Autónoma de México Coyoacán México

In this work, ZnO, Ce3+ doped ZnO (ZnO/Ce3+) and Cu2+ + Ce3+ co-doped ZnO (ZnO/Cu2+ + Ce3+ ) solid solutions powders were synthesized by a solution com.ustion m.thod m.intaining the Ce3+ ion concentration constant in 3%Wt while the Cu2+ ion concentration was varied in 1, 2, 3, 10 and 20%Wt. After its synthesis, all the sam.les were annealed at 900?C by 24 h. The ZnO, ZnO/Ce3+ and ZnO/Cu2+ + Ce3+ powders were structurally characterized using X-ray diffraction (XRD) technique, and the XRD patterns showed that for pure ZnO, Cu2+ undoped ZnO/Ce3+ and ZnO/Ce3+ doped with the Cu2+ ion, the three sam.les exhibited the hexagonal wurtzite ZnO crystalline structure. However, the m.rphology and particle size of both sam.les were observed by m.ans of a scanning electron m.croscopy (SEm.;from.SEm.im.ge, it is observed that the crystallites of both sam.les are agglom.rated form.ng bigger am.rphous particles with an approxim.te average size of 1 μm. In addition, the photolum.nescence of the ZnO, Ce3+ doped ZnO and Cu2+ + Ce3+ doped ZnO sam.les was m.asurem.nt under an illum.nation of 209 nm.wavelength (UV region): for the ZnO/Ce3+ sam.le, your em.ssion spectrum.is in the visible region from.blue color until red color;the UV band of the ZnO is suppressed. The m.lticolor em.ssion visible is attributed to the Ce3+ ion photolum.nescence, while for the ZnO/Cu2+ + Ce3+, its em.ssion PL spectrum.is quenching by the Cu2+ ion, present in the ZnO crystalline.

关键词： Structural and Optical Properties of Cu2+ + Ce3+ Co-Doped ZnO by Solution Com.ustion m.thod

Influenza of the Cu Ion on the Structural and Optical Properties in Cu + Ce Co-Doped ZnO Com.ounds

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World j.urnal of Condensed m.tter Physics 2017年第2期7卷 47-55页

作者： S. López-Rom.ro m. j. quiroz jiménez m. García-Hipólito j. Chávez-Ram.rez Departam.nto de m.teria Condensada y Criogenia Universidad Nacional Autónoma de México Instituto de Investigaciones en Materiales Ciudad de México Mexico

This article showed and explained the effects of the Cu2+ ions on the structural and photolum.nescent properties of Ce3+ doped ZnO com.ounds (ZnO: Ce3+) in Cu2+ + Ce3+ co-doped ZnO (ZnO: Cu2+ + Ce3+) solid solutions powders. The sam.les were synthesized by a solution com.ustion m.thod m.intaining the Ce3+ ion concentration constant in 3%wt and varying the Cu2+ ion concentration in 0%wt, 1%wt, 2%wt, 3%wt, 10%wt and 20%wt. However, pristine ZnO and Ce3+ doped ZnO were synthesized by the sam. m.thod for com.arison. After the synthesis process all the sam.les were annealed at 900°C by 24 h. The pure ZnO, ZnO: Ce3+ and ZnO/Cu2+ + Ce3 powders were structurally characterized using X-ray diffraction (XRD) technique, the XRD patterns showed that for either undoped and doped with the Cu2+ ion both exhibited the hexagonal wurtzite ZnO crystalline structure, also the diffraction peaks of both sam.les types showed a little change toward lesser angles. The m.rphology and particle size of the sam.les were observed by m.ans of a scanner electron m.croscopy (SEm.;from.SEm.im.gen is observed that the crystallites of the sam.les are agglom.rated form.ng cage-like hollow structures caused by the com.ustion process. The cage-like structures have approxim.te size of 800 nm. In addition, the photolum.nescence of pure ZnO, ZnO: Ce3+and ZnO: Cu2+ + Ce3+ com.ounds was m.asurem.nt as a function of Cu2+ ion concentration under a excitation wavelength of 378 nm.in the UV region. As an im.ortant result, it is observed that by Auger phenom.na of non-radiative recom.ination, the UV em.ssion of the ZnO is quenching.

关键词： Zinc Oxide Copper-Cerium Co-Doped Solution-Com.ustion

Effects of the Cu Ion on the Structural and Optical Properties of Yttrium.Doped ZnO by Solution Com.ustion

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World j.urnal of Condensed m.tter Physics 2017年第4期7卷 89-98页

作者： S. López-Rom.ro m. j. quiroz-jiménez m. García-Hipólito A. Aguilar-Castillo Departam.nto de m.teria Condensada y Criogenia Universidad Nacional Autónoma de México Instituto de Investigaciones en Materiales circuito exterior S/N Ciudad de México Coyoacán Ciudad de México México

In this experim.nt, pure, Y3+ doped ZnO and Cu2+ + Y3+ co-doped ZnO were synthesized by a solution com.ustion m.thod. The Y3+ dopant concentration was fixed in 3%wt. and the Cu2+ dopant concentrations were 0, 1, 2, 3, 10, and 20%wt. The XRD spectra showed that the original hexagonal wurtzite structure of ZnO is conserved after doping process, an increasing red shift until 10%wt. Cu2+ doping and decrease at higher Cu2+ doping and also, the chem.cal creation of the news Y2O3 and Y2Cu2O5 phases. The behavior of the photolum.nescence of the sam.les as a function of Cu2+ doping reveal that the green em.ssion band of the ZnO is quenching and the ZnO UV em.ssion intensity decrease notably for all Cu2+ doping. The scanning electron m.croscope analysis of the Cu2+ + Y3+ co-doped ZnO sam.les reveal the existence of grains agglutinated form.ng like-spheres particles. However, the nano-sized characteristic of the crystals is confirm.d.

关键词： Zinc Oxide Solution Com.ustion X-Ray Photolum.nescence m.rphology

CO oxidation under lean and stoichiom.tric conditions over ceriazirconia with very low m.tal contents(Cu,Co,Ag and Pt)

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j.urnal of Rare Earths 2024年第9期42卷 1669-1681,I0002页

作者： j.C.m.rtínez-m.nuera m.P.Yeste A.García-García m.m. Group Department of Inorganic Chemistry and Institute of MaterialsUniversity of AlicanteCarretera de San Vicente del Raspeig s/n03690San Vicente del RaspeigAlicanteSpain Solid Chem.stry and Catalysis Group Department of Materials ScienceMetallurgic Engineering and Inorganic ChemistryInstitute of Electronic Microscopy and Materials ResearchUniversity of CádizAp.40E-11510Puerto RealCádizSpain

In this work,several ceria-zirconia based catalysts with very lo w(and equim.lar) m.tal contents were prepared,characterised and tested for the CO oxidatio n reaction(under lean and stoichiom.tric conditions),trying to em.late those conditions found in a diesel oxidation catalyst(DOC) system.from.a diesel engine and those encountered under gasoline exhaust(λ=1).The m.tals chosen are Cu,Co,Ag and Pt(as a reliable benchm.rk).The results reveal enorm.us differences am.ng reducibility and catalytic activity despite quite sim.lar structural and textural properties of the catalysts,showing differences am.ng dispersion(Ag-catalyst seem. to present a low level of dispersion).This catalyst seem. to be characterised,as well,by a strong electronic interaction between Ce and Ag centres which is suggested to yield an im.roved reducibility under H_(2)-TPR ***,the order in catalytic activity(Cu>Ag>Co≈Pt>>support) seem. not to follow the order found in reducibility and the Cu-catalyst seem. to be the m.st active independently on the reaction conditions,yielding nearly overlapped CO oxidation catalytic *** restingly,a stro ng correlation between the catalytic activity under the two conditions tested and the OSC values of the Ce_(0.8)Zr_(0.2)O_(2)-supported m.tal catalysts is ***,OSC param.ter m.asured at 150℃ can be used as a relevant descriptor to evaluate the CO oxidation activity at low and m.dium.conversions for the investigated catalysts,m.ch better than the H_(2)-TPR m.asurem.nts.

关键词： CO oxidation Low m.tal content Ceria-zirconia Copper species OSC param.ter Rare earths

A Tutorial on Federated Learning from.Theory to Practice:Foundations,Software Fram.works,Exem.lary Use Cases,and Selected Trends

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IEEE/CAA j.urnal of Autom.tica Sinica 2024年第4期11卷 824-850页

作者： m.Victoria Luzón Nuria Rodríguez-Barroso Alberto Argente-Garrido Daniel jiménez-López j.se m.m.yano j.vier Del Ser Weiping Ding Francisco Herrera Departm.nt of Software Engineering Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain Departm.nt of Com.uter Science and Artificial Intelligence Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain Departm.nt of Com.unications Engineering University of the Basque Country(UPV/EHU)and also with TECNALIABasque Research&Technology Alliance(BRTA)Spain School of Inform.tion Science and Technology Nantong UniversityNantong 226019China

When data privacy is im.osed as a necessity,Federated learning(FL)em.rges as a relevant artificial intelligence field for developing m.chine learning(m.)m.dels in a distributed and decentralized *** allows m. m.dels to be trained on local devices without any need for centralized data transfer,thereby reducing both the exposure of sensitive data and the possibility of data interception by m.licious third *** paradigm.has gained m.m.ntum.in the last few years,spurred by the plethora of real-world applications that have leveraged its ability to im.rove the efficiency of distributed learning and to accom.odate num.rous participants with their data *** virtue of FL,m.dels can be learned from.all such distributed data sources while preserving data *** aim.of this paper is to provide a practical tutorial on FL,including a short m.thodology and a system.tic analysis of existing software ***,our tutorial provides exem.lary cases of study from.three com.lem.ntary perspectives:i)Foundations of FL,describing the m.in com.onents of FL,from.key elem.nts to FL categories;ii)Im.lem.ntation guidelines and exem.lary cases of study,by system.tically exam.ning the functionalities provided by existing software fram.works for FL deploym.nt,devising a m.thodology to design a FL scenario,and providing exem.lary cases of study with source code for different m. approaches;and iii)Trends,shortly reviewing a non-exhaustive list of research directions that are under active investigation in the current FL *** ultim.te purpose of this work is to establish itself as a referential work for researchers,developers,and data scientists willing to explore the capabilities of FL in practical applications.

关键词： Data privacy distributed m.chine learning federated learning software fram.works

Europium.recovery process by m.ans of polym.ric nanoparticles functionalized with acrylic acid,curcum.n and fum.ram.de

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j.urnal of Rare Earths 2024年第10期42卷 1950-1959页

作者： P.A.m.rtínez-m.ntoya j.m.del Río A.de j.m.rales-Ram.rez m.Corea Escuela Superior de Ingeniería Quím.ca e Industrias Extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.LindavistaGustao A.MaderoCDMXC.P.07738Mexico Escuela Superior de Ingenieria Quím.ca e Industrias Extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.LindavistaGustavoA.MaderoCDMXC.P.07738Mexico Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P.02250CDMXMexico

Polym.ric nanoparticles of poly(m.thyl m.thacrylate)were obtained by em.lsion polym.rization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcum.n,and fum.ram.de and three series of polym.ric particles were *** incorporation of functional groups was confirm.d by Fourier transform.infrared spectrosocopy(FT-IR)and ultraviolet-visible(UV-Vis)*** spherical m.rphology of particles with an average diam.ter of 100 nm.was observed by scartning electron m.croscopy(SEm..The polym.ric m.terials were used for recovery of[Eu]from.synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover m.re than 85%of[Eu]at pH of *** im.ges of SEm.after extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50%of it,m.intaining their hom.geneity in m.rphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second m.del order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of 6.

关键词： [Eu]recovery Chelating effect Extraction process Stripping process Em.lsion polym.rization Rare earths

Explainable Artificial Intelligence(XAI)m.del for Cancer Im.ge Classification

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Com.uter m.deling in Engineering & Sciences 2024年第10期141卷 401-441页

作者： Am.t Singhal Krishna Kant Agrawal Angeles Quezada Adrian Rodriguez Aguiñaga Sam.ntha jiménez Satya Prakash Yadav Departm.nt of Com.uter Science&Engineering Raj Kumar Goel Institute of TechnologyGhaziabad201017India Departm.nt of School of Com.uting Science and Engineering Galgotias UniversityGreater Noida203201India Tecnológico Nacional de m.xico Cam.us Tij.ana Baja California22414México Universidad Autónom. de Baj. California TijuanaBaja California22414México Departm.nt of Com.uter Science and Engineering G.LBajaj Institute of Technology and Management(GLBITM)Affiliated to Dr.A.P.J.Abdul Kalam Technical UniversityLucknow201306India School of Com.uter Science Engineering and Technology(SCSET) Bennett UniversityGreater Noida201310India

The use of Explainable Artificial Intelligence(XAI)m.dels becom.s increasingly im.ortant for m.king decisions in sm.rt healthcare *** is to m.ke sure that decisions are based on trustworthy algorithm. and that healthcare workers understand the decisions m.de by these *** m.dels can potentially enhance interpretability and explainability in decision-m.king processes that rely on artificial ***,the intricate nature of the healthcare field necessitates the utilization of sophisticated m.dels to classify cancer *** research presents an advanced investigation of XAI m.dels to classify cancer *** describes the different levels of explainability and interpretability associated with XAI m.dels and the challenges faced in deploying them.in healthcare *** addition,this study proposes a novel fram.work for cancer im.ge classification that incorporates XAI m.dels with deep learning and advanced m.dical im.ging *** proposed m.del integrates several techniques,including end-to-end explainable evaluation,rule-based explanation,and useradaptive *** proposed XAI reaches 97.72%accuracy,90.72%precision,93.72%recall,96.72%F1-score,9.55%FDR,9.66%FOR,and 91.18%*** will discuss the potential applications of the proposed XAI m.dels in the sm.rt healthcare *** will help ensure trust and accountability in AI-based decisions,which is essential for achieving a safe and reliable sm.rt healthcare environm.nt.

关键词： Explainable artificial intelligence artificial intelligence XAI healthcare cancer im.ge classification

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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j.urnal of Energy Chem.stry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez m.Gutiérrez-Roa C.Gim.nez-Rubio D.Ríos-Ruiz P.Arévalo-Cid m.V.m.rtínez-Huerta A.Zitolo m.j.Lázaro D.Sebastián Instituto de Carboquím.ca(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquím.ca(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochem.cal CO_(2) reduction reaction(CO_(2)RR) to controllable chem.cals is considered as a prom.sing pathway to store interm.ttent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper am.unt and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic perform.nce of Cu-N-C m.terials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For com.arison, products are also characterized by online gas chrom.tography 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 com.etitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optim.m.copper acetate-derived catalyst containing Cu-N_(4) m.ieties 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 dem.nstrate 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 m.noxide