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Chinese Physics B 2014年第7期23卷 712-716页

作者：肖仁政张早娣 vasiliy o.pelenovich 王泽松张瑞李慧刘雍黄志宏付德君 Key Laboratory of Artificial Micro- and Nano-Materials of Ministry of Education School of Physics and TechnologyWuhan University Department of Physics and Technology Huazhong Normal University

Crystalline BiFeo3 （BFo） films each with a crystal structure of a distorted rhombohedral perovskite are characterized by X-ray diffraction （XRD） and high-resolution electron microscopy （HRTEM）. The diffusion of silicon atoms from the substrate into the BiFeo3 film is detected by Rutherford backscattering spectrometry （RBS）. The element analysis is per- formed by energy dispersive X-ray spectroscopy （EDS）. Simulation results of RBS spectrum show a visualized distribution of silicon. X-ray photoelectron spectroscopy （XPS） indicates that a portion of silica is formed in the diffusion process of silicon atoms. Ferroelectric and weak ferromagnetic properties of the BFo films are degraded due to the diffusion of silicon atoms. The saturation magnetization decreases from 6.11 down to 0.75 emu/g, and the leakage current density increases from 3.8 × 10^-4 upto7.1 × 10^-4 A/cm-2.

关键词： ferroelectric ferromagnetic diffusion silicon

optical and magnetic properties of InFeP layers prepared by Fe^+ implantation

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Chinese Physics B 2013年第10期22卷 397-400页

作者：周霖尚艳霞王泽松张瑞张早娣 vasiliy o.pelenovich 付德君 Kang Tae Won School of Physics and Technology Wuhan University Quantum-Functional Semiconductor Research Center Dongguk University

InFeP layers are prepared by ion implantation of InP with 100-keV Fe＋ ions to a dose of 5 ×10^16 cm-2 and investigated by optical, magnetic, and ion beam analysis measurements. Photoluminescence measurements show a deep-level peak at 1.035 eV due to Fe in InP and two exciton-related luminescences at 1.426 eV and 1.376 eV in the implanted samples annealed at 400℃. Conversion electron Mossbauer spectroscopy reveals a doublet corresponding to Fe3＋ ions in the indium sites. Atomic force microscopy and magnetic force microscopy show that magnetic clusters are formed in the annealing process. The magnetization-field hysteresis loops show ferromagnetic properties persisting up to room temperature with a coercive field of 100 0e （10e = 79.5775 A-m-1）, saturation magnetization of 4.35 × 10-5 emu, and remnant magnetization of 4.4× 10 6 emu.

关键词： ion implantation diluted magnetic semiconductor photoluminescence Rutherford backscatter-ing/channeling

Magnetooptics of non-Kramers Eu^(3+) ions in garnets:analysis complemented by crystal-field splitting modeling calculations

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Journal of Rare Earths 2013年第9期31卷 837-842页

作者： Uygun V.Valiev John B.Gruber Anvar K.Mukhammadiev vasiliy o.pelenovich 付德君 Gary W.Burdick Faculty of Physics National University of Uzbekistan Department of Physics and Astronomy The University of Texas at San Antonio School of Physics and Technology Wuhan University Department of Physics Andrews University

Spectra of absorption, luminescence, magnetic circular dichroism （MCD）, and magnetic circular polarization of lumines- cence （MCPL） in Gd3Ga5o12：Eu3＋ and Eu3Ga3o12 garnets were studied within the visible spectral range at 300 K. Analysis of the spectral and temperature dependences of the magnetooptical and optical spectra made it possible to identify the magneto-dipole （MD） and electro-dipole （ED） 4f→4f transitions occurring between Stark sublevels of the 7FJ （J=1, 2） and 5D0 multiplets in Eua＋-containing garnet structures. Quantum mechanical ＂mixing＂ had significant influence on quasi-degenerate states of the non-Kramers rare-earth Eu3＋ ion for Eu3Gasol2 in MCD due to forbidden MD transition 7F1→SD0 and for GdaGasoiE：EU3＋ in MCPL due to MD 4f→4f transition 5Do→7F1 and forced ED-transition 5Do→7F2. A parameterized Hamiltonian defined to operate within the entire 4f（6） ground electronic configuration of Eu3＋ ion was used to model the experimental Stark levels, including their irreducible rep- resentations and wavefunctions. The crystal-field parameters were determined through a Monte-Carlo method in which nine in- dependent crystal-field parameters, Bkq, were given random starting values and optimized using standard least-squares fitting between calculated and experimental levels. The final fitting standard deviation between 57 calculated-to-experimental levels was 0.73 meV.

关键词： : magnetic circular dichroism magnetic circular polarization luminescence adsorption garnet non-Kramers ion rare earths

Study of doping uniformity of a 200 kV ion implanter by RBS and sheet resistance measurements

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Nuclear Science and Techniques 2016年第3期27卷 40-44页

作者： Hui Li Ze-Song Wang Sheng-Jun Zhang vasiliy o.pelenovich Feng Ren De-Jun Fu Chuan-Sheng Liu Zhi-Wei Ai Key Laboratory of Artificial Micro-and Nano-Materials of Ministry of Education and School of Physics and Technology Wuhan UniversityWuhan 430072China Institute of Ion-Plasma and Laser Technologies Academy of Sciences of UzbekistanTashkent 700135Uzbekistan

The ion implantation uniformity is of vital importance for an ion *** this paper,we report the,uniformity measurement for a large current ion implanter(LC-16 type) by implanting of 190-keV Ar ions into Si to 3×1016 atoms/cm2,followed by Rutherford backscattering spectroscopy(RBS) and sheet resistance measurement providing quantitative information on spatial distribution of *** implant doses obtained from RBS at selected points of the sample give a spatial uniformity of onfirmed by the sheet resistance *** sheet resistance is an indirect method for dose evaluation of ion-implanted samples,RBS provides a competent technique for calibration of the ion implantation *** both measurements show that good uniformity can be achieved for the ion implanter by tuning of the scanning process.

关键词：均匀性测量离子注入机薄层电阻掺杂分布 RBS 卢瑟福背散射离子注入系统剂量评价

Design and experimental testing of a gas cluster ion accelerator

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Chinese Physics C 2017年第8期41卷 143-146页

作者：曾晓梅 vasiliy pelenovich 刘传胜付德君 Key Laboratory of Artificial Micro-and Nano-Materials of Ministry of Education and Hubei Nuclear Solid Physics Key Laboratory School of Physics and TechnologyWuhan UniversityWuhan 430072China

A gas cluster ion beam（GCIB） system with cluster energy up to 12 keV has been designed. To facilitate pumping of the nozzle chamber and increased pressure of the gas source up to 10 atm, pulse mode was used for the gas feeding. Argon was employed as the working gas. To separate monomers from clusters, both electromagnet and retarding electrode were utilized. A maximal pulsed cluster current of 90 nA has been achieved. The shape of pulsed ion beam currents has been analyzed in detail at different applied magnetic and retarding electric fields.

关键词： gas cluster ion beam flow visualization cluster mass separation retarding electrode

Blood biomarkers of Alzheimer’s disease:important considerations for use in clinical practice

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Neural Regeneration Research 2025年第1期20卷 205-206页

作者： Sarah Fullam Sean o’Dowd Antoinette o’Connor Department of Neurology Tallaght University HospitalDublinIreland Academic Unit of Neurology Trinity College DublinIreland

Introduction:Fluid and positron emission tomography(PET)biomarkers that enable the detection of the hallmark proteins of Alzheimer’s disease(AD)(amyloid and tau)have revolutionized our approach to the diagnosis of *** evolution of AD diagnostic criteria to include biological characterization(Alzheimer’s Association Working Group,2023)provides an appropriate framework to reduce levels of clinico-pathologic mismatch and improve in-vivo diagnostic *** the therapeutic landscape for neurodegenerative disease evolves,it is increasingly incumbent on clinicians to provide timely,and pathologically precise diagnoses for ***,the expensive and invasive nature of these tests limits their scalability.

关键词： Blood Alzheimer diagnosis

Specific features of Eu^(3+) and Tb^(3+) magnetooptics in gadolinium-gallium garnet (Gd_3Ga_5o_(12))

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Journal of Rare Earths 2011年第8期29卷 776-782页

作者： Uygun V. Valiev John B. Gruber 付德君 vasiliy o. pelenovich Gary W. Burdick Mariya E. Malysheva Faculty of Physics National University of Uzbekistan Department of Physics and Astronomy The University of Texas at San Antonio Department of Physics Wuhan University Department of Physics Andrews University

We reported magnetooptical properties of Eu3＋（4f（6）） and Tb3＋（4f（8）） in single crystals of Gd3Ga5o12 （GGG）, Y3Ga5o12 （YGG）, and Eu3＋（4f（6）） in Eu3Ga5o12 （EuGG） for both ions occupying sites of D2 symmetry in the garnet structure. Absorption, luminescence, and magnetic circular polarization of luminescence （MCPL） spectra of Tb3＋ in GGG and YGG and absorption and magnetic circular dichroism （MCD） of Eu3＋ in EuGG were studied. The data were obtained at 85 K and room temperature （RT）. Magnetic susceptibility of Eu3＋ in EuGG was also measured between 85 K and RT. The magnetooptical and magnetic susceptibility data were modeled using the wavefunctions of the crystal-field split energy （Stark） levels of Eu3＋ and Tb3＋ occupying D2 sites in the same garnets. The results reported gave a precise determination of these Stark level assignments and confirmed the symmetry labels （irreducible representations） of the closely-spaced Stark levels （quasi-doublets） found in the 5D1 （Eu3＋） and 5D4 （Tb3＋） multiplets. Ultraviolet （UV） excitation （300 nm） of the 6PJ and 6IJ states of Gd3＋ in the doped GGG crystals led to emission from 5D4 （Tb3＋） and 5D1 and 5D0 （Eu3＋） through radiationless energy transfer to the 4f（n–1）5d band of Tb3＋ and to UV quintet states of Eu3＋. The temperature-dependent emission line shapes and line shifts of the magnetooptical transitions excited by UV radiation suggested a novel way to explore energy transfer mechanisms in this rare-earth doped garnet system.

关键词： magnetic circular polarization of luminescence magnetic circular dichroism absorption quantum qutting energy transfer magnetic susceptibility rare earths

Neuroinflammation revisited through the microglial lens

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Neural Regeneration Research 2025年第7期20卷 1989-1990页

作者： Renato Socodato João B.Relvas Institute of Research and Innovation in Health(i3S)and Institute for Molecular and Cell Biology(IBMC) University of PortoPortoPortugal Department of Biomedicine Faculty of Medicine of the University of Porto(FMUP)PortoPortugal

Neuroimmunology is emerging as a pivotal field,shedding light on the intricate dialogues between the central nervous system(CNS)and the immune *** exploration is particularly significant in understanding microglia,the CNS’s innate immune cells,beyond the conventional conflation of“neuroinflammation”and“microglial activation.”This conflation has clouded the true complexity of these processes,potentially stalling scientific progress and the development of new *** challenge the long-standing perspectives that have oversimplified these interactions,advocating for a deeper exploration of the dynamic relationship between neuroinflammation and microglial *** dissecting specific molecular pathways,we aim to illuminate their elaborate roles in neuroinflammatory responses,especially in the context of Alzheimer’s disease(AD).Here,neuroinflammation is not merely a passive observer or a direct antagonist but a complex agent in the disease’s *** article calls for a significant paradigm shift towards an integrative,multi-omics approach to *** such a comprehensive framework is crucial for advancing our understanding of neuroinflammatory conditions and paving the way for targeted therapeutic strategies for brain diseases.

关键词： inflammation simplified activation

Contribution of mechanical forces to structural synaptic plasticity:insights from 3D cellular motility mechanisms

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Neural Regeneration Research 2025年第7期20卷 1995-1996页

作者： Rita o.Teodoro Mafalda Ribeiro Ramos Lara Carvalho iNoVA4Health NOVA Medical School|Faculdade de Ciências MédicasNMS|FCMUniversidade Nova de LisboaLisboaPortugal

Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no ***-intrinsic properties such as membrane lipid composition,abundance of mechanosensors,and cytoskeletal dynamics make cells more or less likely to sense these *** and extrinsic cues are integrated by cells and this combined information determines the rate and dynamics of membrane protrusion growth or retraction(Yamada and Sixt,2019).Cell protrusions are extensions of the plasma membrane that play crucial roles in diverse contexts such as cell migration and neuronal synapse *** the nervous system,neurons are highly dynamic cells that can change the size and number of their pre-and postsynaptic elements(called synaptic boutons and dendritic spines,respectively),in response to changes in the levels of synaptic activity through a process called *** plasticity is a hallmark of the nervous system and is present throughout our lives,being required for functions like memory formation or the learning of new motor skills(Minegishi et al.,2023;Pillai and Franze,2024).

关键词： plasticity structural mechanisms

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher J.o’Connell Matthew J.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA James L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain injury(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic