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Journal of semiconductors 2024年第9期45卷 28-35页

作者： leonarde N.Rodrigues Wesley F.Inoch Marcos l.F.Gomes Odilon d.d.Couto Jr. Bráulio s.Archanjo sukarno O.Ferreira Physics department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de Física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of Metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2d character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0d) 0d nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate

Effect of Ta_(2)O_(5)nanoparticles on bioactivity,composition,structure,in vitro and in vivo behavior of PEO coatings on Mg-alloy

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Journal of Magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： d.V.Mashtalyar I.M.Imshinetskiy V.V.Kashepa K.V.Nadaraia M.A.Piatkova A.I.Pleshkova K.A.Fomenko A.Yu.Ustinov s.l.sinebryukhov s.V.Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical dermatovenerological dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vivo,and biocompatibility of coatings containing Ta_(2)O_(5),which are obtained by plasma electrolytic oxidation(PEO)on MA8 magnesium *** obtained coatings demonstrate in vivo biocompatibility and in vitro *** to the base PEO coating,the layers containing Ta_(2)O_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of Ta_(2)O_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEO coatings containing Ta_(2)O_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings Tantalum pentoxide simulated body fluid(sBF) Apatite formation Histology

discovery of new MAX-phase-like layered ternary carbide V_(8)P_(6)C:Crystal structure,thermal expansion,and elastic properties

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Journal of Materials science & Technology 2024年第7期174卷 55-62页

作者： H.X.Chen l.sheng Z.l.Zhang X.C.Wen d.l.Yang X.Y.Ye P.Q.dai school of Materials science and Engineering Fujian University of TechnologyFuzhou 350118China Beijing synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China Fujian Provincial Key laboratory of Advanced Materials Processing and Application Fuzhou 350118China state Key laboratory of structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

due to the laminated structure,MAX phases and MAX-phase-like compounds possess outstanding dam-age tolerance capability with good thermal/electrical conductivity and other charming functional prop-erties,showing a bright future for structural-functional ***,a new MAX-phase-like ternary car-bide V_(8)P_(6)C with layered characteristics was *** to the alternate stacking of hexagonal-arranged M/A/X atom layers in MAX phases,V_(8)P_(6)C has a layered structure formed by a repeated stacking of the slabs consisting of V_(6)C-octahedrons and VP 6-distorted-octahedrons in three-atomic layers *** thermal expansion anisotropy was revealed,with the thermal expansion coefficients(TECs)along a-axis,c-axis,and the average value,equal toα_(a)=8.55(5)μK^(−1),α_(c)=10.23(5)μK^(−1),andα_(l)=9.14(5)μK^(−1),*** dilation along the c-axis was mainly dominated by out-plane V-P bonds be-tween layered *** to the pressure-dependent lattice parameters,the polycrystalline bulk modulus(B_(0)=185(9)GPa)and high compressibility anisotropy factor(B_(a)/B_(c)=1.64)was ***-while,the second-order elastic constants were calculated,and the elastic moduli,E=303 GPa,B=198 GPa,G=122 GPa,andν=0.246,were *** the weak connection between layer slabs by out-plane V1-P bond was revealed by the bond stiffness model,with a bond stiffness close to the M-A bond in MAX ***,good damage tolerance capability was predicted according to Paugh’s ratio(G/B=0.616)and Cauchy pressure(P_(a)=0 GPa,P_(c)=-7.5 GPa),even better than those of typical MAX *** discovery of V_(8)P_(6)C provides a new member of MAX-phase-like damage-tolerant ceramic with relatively low density,moderate thermal expansion,and anisotropic compressibility,and the unique lay-ered structure is inspiring for exploring new layered ternary ceramics.

关键词： New ternary carbide MAX phase Thermal expansion Elastic constants Anisotropy

Comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

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Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková s.Šašek J.dittrich M.Knapek F.lukáˇc d.Koutný J.Jaroš R.Král Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the Czech Academy of sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(sPs)and selective laser melting(slM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the slM material and unmeasurably low porosity in the sPs *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the slM and sPs materials,*** corrosion resistance of the sPs material in 0.1 M NaCl solution was superior to the slM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the slM *** the other hand,one of the primary outcomes of this study is that the sPs consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength Corrosion resistance

Highly defective dark TiO_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： E.d.Fakhrutdinova O.A.Reutova T.A.Bugrova I.Yu.Ovsyuk l.s.Kibis O.A.stonkus d.B.Vasilchenko O.V.Vodyankina V.A.svetlychnyi National Research Tomsk state University TomskRussia 634050 Novosibirsk state University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via puls.d.l.ser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (sMsI) eff ect of the transfer of electron density from the electron-saturated defects on the TiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the sMsI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/TiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： dark(black)TiO_(2) Puls.d.l.ser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

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

Photometric and spectroscopic study of Ten low Mass Ratio Contact Binary systems:Orbital stability,O'Connell Effect and Infrared Calcium line Filling

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Research in Astronomy and Astrophysics 2024年第8期24卷 212-222页

作者： surjit s.Wadhwa Adam Popowicz Raúl Michel Petar Kostić Oliver Vince Nick F.H.Tothill Ain Y.de Horta Miroslav d.Filipović school of science Western Sydney UniversityLocked Bag 1797PenrithNSW 2751Australia department of Electronics Electrical Engineering and MicroelectronicsSilesian University of TechnologyAkademicka 1644120 GliwicePoland Instituto de Astronomía UNAM.A.P.87722800 EnsenadaBCMéxico Astronomical Observatory Volgina 711060 BelgradeSerbia

low mass ratio contact binary systems are more likely to have unstable orbits and potentially *** addition,such systems exhibit characteristics such as starspots and high energy emissions(UV)suggestive of chromospheric and magnetic *** curve modeling of ten contact binary systems is *** were found to be of extreme low mass ratio ranging from 0.122 to 0.24 and three were found to be potentially unstable and possible merger *** of the infrared calcium absorption lines is a marker of increased chromospheric *** use the available large sky Area Multi-Object Fiber spectroscopic Telescope spectra along with matched standard spectra(broadened for rotation)to measure the excess filling of the central core depression flux of the two main infrared calcium absorption linesλ8542 andλ*** find that all reported contact binaries have excess filling of the core flux in the infrared calcium *** of the systems reported were also observed by the Galaxy Evolution Explorer mission and we find that all three have features of excess ultraviolet emissions further adding evidence for increased chromospheric activity in low mass ratio contact *** of both orbital stability and absorption line filling is dependent on the determination of geometric and absolute parameters from light curve *** an insignificant number of contact binary light curves exhibit the O’Connell effect,usually attributed to *** discuss the inclusion of starspots in light curve solutions and how they influence the geometric and absolute parameters.

关键词： (stars)binaries eclipsing-techniques photometric-stars chromospheres

The relationship between dNA fragmentation and the intensity of morphologically abnormal human spermatozoa

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Asian pacific Journal of Reproduction 2024年第1期13卷 22-27页

作者： Mercedes González-Martínez Pascual sánchez-Martín Carmen lópez-Fernández stephen d.Johnston Jaime Gosálvez Clínica Ginemed Unidad de ReproducciónSevillaSpain department of Biology Universidad Autónoma de MadridCantoblancoMadridSpain school of Environment The University of QueenslandGattonAustralia school of Veterinary science The University of QueenslandGattonAustralia

Objective:To determine the relationship between teratozoospermia and sperm dNA fragmentation(sdF)in the human ***:This retrospective study included 100 normozoospermic men as a control cohort(abnormal forms>14%),210 patients with a high level of abnormal forms(≤4%)and 65 patients presenting with a moderate level of abnormal forms(>4%to≤14%)based on the World Health Organization *** morphology was assessed using bright field *** dNA fragmentation was assessed using the sperm chromatin dispersion ***-parametric analyses were conducted to examine the relationship between abnormal sperm morphology and sperm dNA fragmentation;receiver operating characteristic(ROC)analyses were conducted to assess sensitivity and specificity of this ***:A correlation analysis revealed that the higher the proportion of abnormal spermatozoa in the ejaculate,the higher the level of sdF(spearman's Rho=-0.230;Psignificant differences in the proportion of sdF were found when all cohorts were compared(Pse significant differences were also retained when the different cohorts were compared *** analysis showed a moderate but significant predictive value for sdF to differentiate patients with different levels of ***:Although analysis of a more continuous range of values for teratozoospermia would help further clarify any causal relationship with sdF,there is clearly a synergistic or coincident affiliation between these variables that needs to be acknowledged by the clinician when interpreting the spermiogram.

关键词： Teratozoospermia sperm morphology sperm dNA fragmentation Male factor Human reproduction Human fertility

Further investigation on the fusion of ^(6)li with ^(209)Bi target at near-barrier energies

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Chinese Physics C 2024年第7期48卷 106-117页

作者：张高龙焦振威张广鑫 M.R.Cortes 胡世鹏钱建强 d.Mengoni 屈卫卫李聪博郑云张焕乔孙慧斌王楠张春雷 J.J.Valiente-dobón d.Testov M.Mazzocco A.Gozzelino C.Parascandolo d.Pierroutsakou M.la Commara A.Goasduff d.Bazzacco d.R.Napoli F.Galtarossa F.Recchia A.Illana s.Bakes I.Zanon s.Aydin G.de Angelis M.siciliano R.Menegazzo s.M.lenzi J.l.Ferreira J.Rangel serkan Akkoyun l.F.Canto J.lubian school of Physics Beihang UniversityBeijing 100191China sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Instituto de Física Universidade Federal Fluminense24210-340NiteróiRio de JaneiroBrazil Institute for Advanced study in Nuclear Energy&safety Shenzhen UniversityShenzhen 518060China shenzhen Key laboratory of Research and Manufacture of High Purity Germanium Materials and Fetectors Shenzhen UniversityShenzhen 518060China INFN Sezione di PadovaPadovaItaly dipartimento di fisica Astronomia dell'Universita di padova PadovaItaly state Key laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China China Institute of Atomic Energy Beijing 102413China The Key laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China INFN Laboratori Nazionali di LegnaroI-35020 LegnaroItaly INFN Sezione di NapoliI-80126 NapoliItaly dipartimento di Farmacia Universitàdi Napoli"Federico II"I-80131 NapoliItaly department of Natural and Mathematical sciences Faculty of EngineeringTarsus University33480 MersinTurkiye Physics division Argonne National LaboratoryLemont-ILUSA departamento de Matemaética Física e Computaç˜ao Universidade do Estado do Rio de JaneiroFaculdade de Tecnologia27537-000ResendeRio de JaneiroBrazil department of Physics Sivas Cumhuriyet UniversitySivasTurkey Instituto de Física Universidade Federal do Rio de JaneiroCP 6852821941-972Rio de JaneiroBrazil

The complete and incomplete fusion cross sections for ^(6)li+^(209)Bi were measured using the in-beamγ-ray method around the Coulomb *** cross sections of(deuteron captured)incomplete fusion(ICF)products were re-quantified experimentally for this reaction *** results reveal that the ICF cross section is equivalent to that of complete fusion(CF)above the Coulomb barrier and dominant near or below the Coulomb barrier.A theoretical calculation based on the continuum discretized coupled channel(CdCC)method was performed for the aforementioned CF and ICF cross sections;the result is consistent with the *** universal fusion function(UFF)was also compared with the measured CF cross section for different barrier parameters,demonstrating that the CF suppression factor is significantly influenced by the choice of potential,which can reflect both dynamic and static effects of breakup on the fusion process.

关键词： cross section incomplete fusion suppression factor weakly bound nuclei

Vanillylacetone attenuates cadmium chloride-induced hippocampal damage and memory loss through upregulation of nuclear factor erythroid 2-related factor 2 gene and protein expression

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Neural Regeneration Research 2024年第12期19卷 2750-2759页

作者： Fahaid H.A.l-Hashem salah O.Bashir Amal F.dawood Moutasem s.Aboonq Ismaeel Bin-Jaliah Abdulaiziz M.Al-Garni Mohamed d.Morsy department of Physiology College of MedicineKing Khalid UniversityAbhaSaudi Arabia department of Basic Medical sciences College of MedicinePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia department of Physiology College of MedicineTaibah UniversityAl-Madinah Al-MunawwarahSaudi Arabia department of Medicine College of MedicineKing Khalid UniversityAbhaSaudi Arabia

Memory loss and dementia are major public health concerns with a substantial economic *** stress has been shown to play a crucial role in the pathophysiology of hippocampal damage-induced memory *** investigate whether the antioxidant and anti-inflammatory compound vanillyla cetone(zingerone) can protect against hippocampal damage and memory loss induced by cadmium chloride(CdCl_(2)) administration in rats,we explo red the potential involvement of the nuclear factor erythroid 2-related factor 2(Nrf2) signaling pathway,which is known to modulate oxidative stress and *** healt hy male Wistar rats were divided into five groups:vehicle-treated(control),vanillylacetone,CdCl_(2),vanillylacetone+ CdCl_(2),vanillylacetone+ CdCl_(2)+ brusatol(a selective pharmacological N rf2inhibitor) *** effectively attenuated CdCl_(2)-induced damage in the dental gyrus of the hippocampus and improved the memory function assessed by the Morris Water Maze ***,vanillylacetone markedly decreased the hippocampal tissue levels of inflammatory biomarkers(interleukin-6,tumor necrosis factor-α,intracellular cell adhesive molecules) and apoptosis biomarkers(Bax and cleaved caspase-3).The control and CdCl_(2)-treated groups treated with va nillylacetone showed reduced generation of reactive oxygen species,decreased malondialdehyde levels,and increased superoxide dismutase and glutathione activities,along with significant elevation of nuclear Nrf2 mRNA and protein expression in hippocampal *** the protective effects of vanillylacetone we re substantially blocked by the co-administration of brusatol(a selective N rf2 inhibitor).Va nillylacetone mitigated hippocampal damage and memory loss induced by CdCl_(2),at least in part, by activating the nuclear transcription factor ***,vanillylacetone exerted its potent antioxidant and antiinflammatory actions.

关键词： hippocampus neuroprotective Nrf2 gene oxidative stress vanillylacetone