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Synchronized off-harmonic probe laser with highly variable pulse duration for laser-plasma interaction experiments

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High Power Laser Science and Engineering 2024年第1期12卷 99-107页

作者： j.Hornung Y.Zobus H.Lorenté c.Brabetz B.Zielbauer V.Bagnoud GSI Helmholtzzentrum für Schwerionenforschung GmbH DarmstadtGermany Institut d’Optique UniversitéParis-SaclayPalaiseauFrance Institut für Angewandte Physik Technische Universität DarmstadtDarmstadtGermany

This paper presents the development and experimental utilization of a synchronized off-harmonic laser system designed as a probe for ultra-intense laser±plasma interaction experiments. The system exhibits a novel seed-generation design,allowing for a variable pulse duration spanning over more than three orders of magnitude, from 3.45 picoseconds to 10 nanoseconds. This makes it suitable for various plasma diagnostics and visualization techniques. In a side-view configuration, the laser was employed for interferometry and streaked shadowgraphy of a laser-induced plasma while successfully suppressing the self-emission background of the laser±plasma interaction, resulting in a signal-to-self-emission ratio of 110 for this setup. These properties enable the probe to yield valuable insights into the plasma dynamics and interactions at the PHELIX facility and to be deployed at various laser facilities due to its easy-to-implement design.

关键词： interferometry laser-plasma interaction off-harmonic probe laser streaked shadowgraphy

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cOVID-19 vaccination produces exercise-responsive SARS-coV-2 specific T-cells regardless of infection history

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journal of Sport and Health Science 2024年第1期13卷 99-107页

作者： Kyle A.Smith Tiffany M.Zúñiga Forrest L.Baker Helena Batatinha charles R.Pedlar Shane c.Burgess Michael P.Gustafson Emmanuel Katsanis Richard j.Simpson School of Nutritional Sciences and Wellness The University of ArizonaTucsonAZ 85721USA Department of Pediatrics The University of ArizonaTucsonAZ 85724USA Faculty of Sport Allied Health and Performance ScienceSt.Mary's UniversityTwickenham TW14SXUK Institute of Sport Exercise and Health University College LondonLondon WC1E 7HUUK Department of Animal and comparative Biomedical Sciences The University of ArizonaTucsonAZ 85721USA The University of Arizona cancer center The University of ArizonaTucsonAZ 85719USA Laboratory Medicine and Pathology Mayo Clinic ArizonaPhoenixAZ 85054USA Department of Immunobiology The University of ArizonaTucsonAZ 85724USA Department of Medicine The University of ArizonaTucsonAZ 85724USA Department of Pathology The University of ArizonaTucsonAZ 85724USA

Background:The mobilization and redistribution of severe acute respiratory syndrome coronavirus 2(SARS-coV-2)specific T-cells and neutralizing antibodies(nAbs)during exercise is purported to increase immune surveillance and protect against severe coronavirus disease 2019(cOVID-19).We sought to determine if cOVID-19 vaccination would elicit exercise-responsive SARS-coV-2 T-cells and transiently alter nAb ***:Eighteen healthy participants completed a 20-min bout of graded cycling exercise before and/or after receiving a cOVID-19 *** major leukocyte subtypes were enumerated before,during,and after exercise by flow cytometry,and immune responses to SARS-coV-2 were determined using whole blood peptide stimulation assays,T-cell receptor(TcR)-βsequencing,and SARS-coV-2 nAb ***:cOVID-19 vaccination had no effect on the mobilization or egress of major leukocyte subsets in response to intensity-controlled graded ***,non-infected participants had a significantly reduced mobilization of cD4+and cD8+naive T-cells,as well as cD4+central memory T-cells,after vaccination(synthetic immunity group);this was not seen after vaccination in those with prior SARS-coV-2 infection(hybrid immunity group).Acute exercise after vaccination robustly mobilized SARS-coV-2 specific T-cells to blood in an intensity-dependent *** groups mobilized T-cells that reacted to spike protein;however,only the hybrid immunity group mobilized T-cells that reacted to membrane and nucleocapsid *** increased significantly during exercise only in the hybrid immunity ***:These data indicate that acute exercise mobilizes SARS-coV-2 specific T-cells that recognize spike protein and increases the redistribution of nAbs in individuals with hybrid immunity.

关键词： Anti-viral cOVID-19 Exercise immunology SARS-coV-2 T-cells Vaccine

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Theory and classification of mass extinction causation

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National Science Review 2024年第1期11卷 16-36页

作者： Thomas j.Algeo jun Shen State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13c values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13c values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

STcF conceptual design report (Volume 1): Physics & detector

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Frontiers of physics 2024年第1期19卷 1-154页

作者： M.Achasov X.c.Ai L.P.An R.Aliberti Q.An X.Z.Bai Y.Bai O.Bakina A.Barnyakov V.Blinov V.Bobrovnikov D.Bodrov A.Bogomyagkov A.Bondar I.Boyko Z.H.Bu F.M.cai H.cai j.j.cao Q.H.cao X.cao Z.cao Q.chang K.T.chao D.Y.chen H.chen H.X.chen j.F.chen K.chen L.L.chen P.chen S.L.chen S.M.chen S.chen S.P.chen W.chen X.chen X.F.chen X.R.chen Y.chen Y.Q.chen H.Y.cheng j.cheng S.cheng T.G.cheng j.P.Dai L.Y.Dai X.c.Dai D.Dedovich A.Denig I.Denisenko j.M.Dias D.Z.Ding L.Y.Dong W.H.Dong V.Druzhinin D.S.Du Y.j.Du Z.G.Du L.M.Duan D.Epifanov Y.L.Fan S.S.Fang Z.j.Fang G.Fedotovich c.Q.Feng X.Feng Y.T.Feng j.L.Fu j.Gao Y.N.Gao P.S.Ge c.Q.Geng L.S.Geng A.Gilman L.Gong T.Gong B.Gou W.Gradl j.L.Gu A.Guevara L.c.Gui A.Q.Guo F.K.Guo j.c.Guo j.Guo Y.P.Guo Z.H.Guo A.Guskov K.L.Han L.Han M.Han X.Q.Hao j.B.He S.Q.He X.G.He Y.L.He Z.B.He Z.X.Heng B.L.Hou T.j.Hou Y.R.Hou c.Y.Hu H.M.Hu K.Hu R.j.Hu W.H.Hu X.H.Hu Y.c.Hu j.Hua G.S.Huang j.S.Huang M.Huang Q.Y.Huang W.Q.Huang X.T.Huang X.j.Huang Y.B.Huang Y.S.Huang N.Hüsken V.Ivanov Q.P.ji j.j.jia S.jia Z.K.jia H.B.jiang j.jiang S.Z.jiang j.B.jiao Z.jiao H.j.jing X.L.Kang X.S.Kang B.c.Ke M.Kenzie A.Khoukaz I.Koop E.Kravchenko A.Kuzmin Y.Lei E.Levichev c.H.Li c.Li D.Y.Li F.Li G.Li G.Li H.B.Li H.Li H.N.Li H.j.Li H.L.Li j.M.Li j.Li L.Li L.Li L.Y.Li N.Li P.R.Li R.H.Li S.Li T.Li W.j.Li X.Li X.H.Li X.Q.Li X.H.Li Y.Li Y.Y.Li Z.j.Li H.Liang j.H.Liang Y.T.Liang G.R.Liao L.Z.Liao Y.Liao c.X.Lin D.X.Lin X.S.Lin B.j.Liu c.W.Liu D.Liu F.Liu G.M.Liu H.B.Liu j.Liu j.j.Liu j.B.Liu K.Liu K.Y.Liu K.Liu L.Liu Q.Liu S.B.Liu T.Liu X.Liu Y.W.Liu Y.Liu Y.L.Liu Z.Q.Liu Z.Y.Liu Z.W.Liu I.Logashenko Y.Long c.G.Lu j.X.Lu N.Lu Q.F.Lü Y.Lu Y.Lu Z.Lu P.Lukin F.j.Luo T.Luo X.F.Luo Y.H.Luo H.j.Lyu X.R.Lyu j.P.Ma P.Ma Y.Ma Y.M.Ma F.Maas S.Malde D.Matvienko Z.X.Meng R.Mitchell A.Nefediev Y.Nefedov S.L.Olsen Q.Ouyang P.Pakhlov G.Pakhlova X.Pan Y.Pan E.Passemar Y.P.Pei H.P.Peng L.Peng X.Y.Peng X.j.Peng K.Peters S.Pivovarov E.Pyata B.B.Qi Y.Q.Qi W.B.Qian Y.Qian c.F.Qiao j.j.Qin j.j.Qin L.Q.Qin X.S.Qin T.L.Qiu j.Rademacker c.F.Redmer H.Y.Sang Anhui University Hefei 230039China Beihang University Beijing 100191China Budker Institute of Nuclear Physics Novosibirsk 630090Russia cAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China cavendish Laboratory University of CambridgeJJ Thomson AveCambridge CB30HEUnited Kingdom central china Normal University Wuhan 430079China central South University Changsha 410083China china University of Geosciences Wuhan 430074China china University of Mining and Technology Xuzhou 221116China École Polytechnique Fédérale de Lausanne(EPFL) LausanneSwitzerland Fudan University Shanghai 200433China Goethe University Frankfurt D-60325 Frankfurt am MainGermany Guangxi Normal University Guilin 541004China Guangxi Uninversity Nanning 530004China Hangzhou Institute for Advanced Study UCASHangzhou 310024China Hebei Normal University Shijiazhuang 050024China Hebei University Baoding 071002China Hefei University of Technology Hefei 230601China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China High Energy Physics center Chung-Ang UniversitySeoul 06974Korea Higher School of Economy 11 Pokrovsky Bulvar Moscow 109028Russia Huangshan University Huangshan 245000China Hubei University of Automotive Technology Shiyan 442002China Hunan Normal University Changsha 410081China Hunan University of Science and Technology Xiangtan 411201China Hunan University Changsha 410082China Indiana University BloomingtonIndiana 47405USA Inner Mongolia University Hohhot 010021China Institute of Advanced Science Facilities Shenzhen 518107China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Institute of Physics Academia SinicaTaipeiTaiwan 11529China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China jilin University Changch

The superτ-charm facility(STcF)is an electron–positron collider proposed by the chinese particle physics *** is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or *** STcF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPcII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard *** STcF project in china is under development with an extensive R&D *** document presents the physics opportunities at the STcF,describes conceptual designs of the STcF detector system,and discusses future plans for detector R&D and physics case studies.

关键词： electron–positron collider tau-charm region high luminosity STcF detector conceptual design

Mid-term survival of the Optimys short stem: A prospective case series of 500 patients

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World journal of Orthopedics 2024年第3期15卷 257-265页

作者： Bryan Hamans Sheryl de Waard Sjoerd Kaarsemaker Esther R c janssen Inger N Sierevelt Gino M M j Kerkhoffs Daniël Haverkamp Department of Orthopaedic Surgery Xpert ClinicAmsterdam 1101EANetherlands Department of Orthopedic Surgery Amsterdam University Medical CenterAmsterdam 1105 AZNetherlands Esther R c janssen Department of Orthopaedic SurgeryViecuri Medisch CentrumVenlo 5912 BLNetherlands centre for Orthopaedic Research Spaarne ZiekenhuisHoofddorp 2134 TMNetherlands Department of Orthopaedic Surgery and Sports Medicine Amsterdam UMC-Location AMCAmsterdam 1105 AZNetherlands Department of Orthopedic Surgery Xpert Orthopedic Surgery ClinicAmsterdam 1101 EANetherlands

BAcKGROUND In recent years,there has been an increase in the number of total hip arthroplasty procedures in the younger patient *** active group has higher expectations of their prosthesis in comparison to the older population,and there is a greater physical demand for the *** femoral stems were in-troduced to retain proximal bone stock and joint biomechanics and became more common to implant in this specific ***,the long-term survival and functional outcomes of various short stems are still being investigated in different *** To determine the 5-year survival of the Optimys hip *** This was a prospective multicenter cohort study of 500 patients conducted in two hospitals in the *** patients received the Optimys short stem(Mathys Ltd,Bettlach,Switzerland).The primary outcome measure was survival of the hip stem,with revision as the *** secondary outcome measurements included patient-reported outcome measures(PROMs).Kaplan-Meier analysis was used to calculate the 5-year survival ***-minus-log transformation was performed to calculate the 95%confidence interval(95%cI).Mixed model analyses were performed to assess the course of the PROMs during the 1st 2 years after *** were modeled separately for the 1st and 2nd years to calculate the yearly change in PROMs during both follow-up periods with accompanying 95%*** The mean age of the total 500 patients was 62.3 years(standard deviation:10.6)and 202 were male(40%).At a median follow-up of 5.5 years(interquartile range:4.5-6.7),7 patients were deceased and 6 revisions were registered,for infection(n=3),subsidence(n=2)and malposition(n=1).This resulted in an overall 5-year survival of 98.8%(95%cI:97.3-99.5).If infection was left out as reason for revision,a stem survival of 99.4%(95%cI:98.1-99.8)was *** questionnaires were completed by 471 patients(94%),317 patients(63%)completed the 1-year follow-up questionna

关键词： Total hip arthroplasty Femoral stem Short stem Optimys Survival 5-year survival Revision PROMs

Structural,morphological,optical and antibacterial performances of rare earth(Sm)-doped ZnO nanorods

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journal of Rare Earths 2024年第11期42卷 2119-2127页

作者： A.Ravi j.Samuel S.Sahaya jude Dhas S.Usharani Turibius Simon D.Senthil Kumar S.K.jasmin Vijitha A.Sivakumar Raju Suresh Kumar c.S.Biju Department of Physics University College of Engineering Department of Physics and Research centre Malankara Catholic College Manonmaniam Sundaranar University Saveetha School of Engineering Saveetha Institute of Medical and Technical SciencesSaveetha University Department of chemistry S.I.V.E.T College Department of Biotechnology Vivekanandha College of Arts and Science for Woman (Autonomous) Department of Physics Vel Tech Rangarajan Dr.Sagunthala R & D Institute of Science and Technology Department of Physics & Research centre Muslim Arts College Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior Institute of GeochemistryChinese Academy of Sciences Department of chemistry College of ScienceKing Saud University Department of Physics St. Alphonsa College of Arts and Science

The significant rise of ultra-violet（UV） radiation and pathogenic infectious bacteria poses a serious threat to global *** researchers' interests are attracted by novel materials with strong UVblocking ability,antibacterial activity and low toxicity to other *** this case,a simple wet chemical method with different annealing temperatures（400,500,and 600℃） was employed to create highly effective rare earth（Sm）-doped ZnO ***（101） plane of wurtzite ZnO shifts towards a lower angle with increasing annealing temperature,according to the X-ray diffraction（XRD） study findings,which additionally establishes the consequence of lattice *** of doublet peaks of Sm 3d(Sm 3d5/2and Sm 3d3/2) in the X-ray photoelectron spectroscopy（XPS） spectrum clearly validates the substitution of Sm3+ions in the 500℃-annealed *** 500℃-annealed nanorods exhibit combined performances of the wide band gap,improved UV absorbance,and vivid green luminescent emission（563 nm）.Additio nally,the nanorods have favorable UV-blocking execution of 96% for UVA at 360 nm,92% for UVB at 320 nm,and 57% for UVc at 225 nm,which is greater than the majority of ZnO-related materials that have been reported up to this *** doping is also appropriate for improving bacterial inhibition against the two studied strains（Escherichia coli and Staphylococcus aureus）,in addition to the intriguing features discussed ***,with maximum inhibition zone diameters of 20±0.72 and 18±0.57 mm,respectively,these nanorods exhibit high inhibitory action against *** and *** bacterial *** rare earth-doped material developed during the current experiment,which was annealed at 500℃,could potentially serve as an effective replacement for UV-blocking and antibacterial material,especially for biomedical applications.

关键词： Wet chemical method rare earth doping Metal oxide UV-Shielding Bacterial inhibition

Optimization of bio-oil production parameters from the pyrolysis of elephant grass (Pennisetum purpureum) using response surface methodology

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clean Energy 2024年第5期8卷 241-251页

作者： Sunday c.Ikpeseni Samuel O.Sada Ufuoma j.Efetobor Henry O.Orugba Mathias Ekpu Hilary I.Owamah jeremiah L.chukwuneke Solomon Oyebisi Uche P.Onochie Department of Mechanical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Delta State PolytechnicP.M.B.3Otefe-OgharaNigeria Department of chemical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of civil Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Nnamdi Azikiwe UniversityP.M.B.2025AwkaNigeria Department of civil Engineering Covenant UniversityP.M.B.1023OttaNigeria Department of civil Engineering The University of the South PacificP.M.B.9072SuvaFiji Department of Mechanical Engineering Delta State University of Science and TechnologyP.M.B.5OzoroNigeria

The need to increase bio-oil yield from biomass and enhance its fuel properties has driven research into optimizing the pyrolysis *** study investigated the influence of three key process parameters—temperature,heating rate,and nitrogen flow rate—on the pyrolysis of elephant grass(Pennisetum purpureum)in a fixed-bed *** surface methodology was used to study the im-pact of the aforementioned variables on bio-oil yield to improve its production *** analysis of the biomass revealed 79.24 wt%volatile matter,14.22 wt%fixed carbon,and 5.86%ash,with ultimate analysis showing 45.44%carbon,5.59%hydrogen,and 40.95%*** high volatile matter content and favourable carbon and hydrogen percentages indicate that elephant grass is a vi-able energy source due to its potential for high bio-oil yield and energy *** resulting bio-oil exhibited a higher heating value of 20.9 Mj/kg,indicating its suitability for various heating applications.A second-order regression model was developed for bio-oil yield,with optimal conditions identified as a temperature of 550°c,a heating rate of 17°c/min,and a nitrogen flow rate of 6 ml/*** study achieved an optimal bio-oil yield of 59.03 wt%,and the model’s high R²value of 0.8683 from analysis of variance analysis confirmed its predictive *** research highlights elephant grass as a sustainable feedstock for bio-oil production,offering valuable insights into optimizing pyrolysis conditions to enhance bio-oil yield,thus advancing biofuel technology.

关键词： renewable energy biomass sustainable feedstock regression model fixed-bed reactor

Evaluating reservoir suitability for large-scale hydrogen storage:A preliminary assessment considering reservoir properties

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Energy Geoscience

Energy Geoscience 2024年第4期5卷 198-211页

作者： chinedu j.Okere james j.Sheng chinedu Ejike Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityLubbockTX79409United States Mewbourne School of Petroleum and Geological Engineering University of OklahomaOK73019United States

With rising demand for clean energy,global focus turns to finding ideal sites for large-scale underground hydrogen storage(UHS)in depleted petroleum reservoirs.A thorough preliminary reservoir evaluation before hydrogen(H_(2))injection is crucial for UHS success and *** criteria for UHS often emphasize economics and chemistry,neglecting key reservoir *** study introduces a comprehensive framework for the reservoir-scale preliminary assessment,specifically tailored for long-term H_(2) storage within depleted gas *** evaluation criteria encompass critical components,including reservoir geometry,petrophysical properties,tectonics,and formation *** illustrate the practical application of this approach,we assess the Barnett shale play reservoir *** assessment unfolds through three key stages:(1)A systematic evaluation of the reservoir's properties against our comprehensive screening criteria determines its suitability for H_(2) storage.(2)Using both homogeneous and multilayered gas reservoir models,we explore the feasibility and efficiency of H_(2) *** phase involves an in-depth examination of reservoir behavior during the injection stage.(3)To enhance understanding of UHS performance,sensitivity analyses investigate the impact of varying reservoir dimensions and injection/production *** findings reveal the following:(a)Despite potential challenges associated with reservoir compaction and aquifer support,the reservoir exhibits substantial promise as an H_(2) storage site.(b)Notably,a pronounced increase in reservoir pressure manifests during the injection stage,particularly in homogeneous reservoirs.(c)Furthermore,optimizing injection-extraction cycle efficiency can be achieved by augmenting reservoir dimensions while maintaining a consistent *** ensure a smooth transition to implementation,further comprehensive investigations are advised,including experimental and numerical studies to address

关键词： Site selection Underground hydrogen storage Preliminary evaluation Depleted petroleum reservoirs Reservoir assessment

Synthesis of coral-like structures of Pr-Yb co-doped YIG: Structural,optical, magnetic and antimicrobial properties

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journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra S.castro-Lopes j.Matilla-Arias Idglan S.de Lima Edson c.Silva-Filho josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. Structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against S. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

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