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电子能量损失谱及其在纳米多层膜研究中的应用

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真空科学与技术学报 2007年第6期27卷 540-544页

作者：肖晓玲代明江周克崧刘敏 d.G.McCulloch P.C.T.Ha d.r.mckenzie M.M.M.Bilek 广州有色金属研究院材料表面工程研究所广州510651 Applied Physics School of Applied SciencesRMIT University Applied and Plasma Physics School of Physics(A28)University of Sydney

本文介绍了电子能量损失谱的基本原理、能量过滤成像分析及应用电子能量损失谱计算碳同素异构体的电子密度和sp2键结构的含量。同时应用透射电镜(TEM)和电镜配置的能量过滤成像系统(gatan imaging filter),结合电子能量损失谱研究类金刚... 详细信息

本文介绍了电子能量损失谱的基本原理、能量过滤成像分析及应用电子能量损失谱计算碳同素异构体的电子密度和sp2键结构的含量。同时应用透射电镜(TEM)和电镜配置的能量过滤成像系统(gatan imaging filter),结合电子能量损失谱研究类金刚石(a-C/Ta-C)和Al/AlN两种纳米多层膜的形态、结构和膜中各元素的分布。结果显示透射电镜观察配合电子能量损失谱在纳米多层膜表征中将会扮演一个重要角色。

关键词：电子能量损失谱透射电镜纳米多层膜 a-C/Ta-C Al/AlN

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAUrABH r.KIrAN d.SINGH r.VAISH V.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSdT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(Hr), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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Electrodeless plasma thrusters for spacecraft: a review

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Plasma Science and Technology 2017年第8期19卷 1-24页

作者： S N BATHGATE M M M BILEK d.r.mckenzie Applied and Plasma Physics School of PhysicsUniversity of Sydney

The physics of electrodeless electric thrusters that use directed plasma to propel spacecraft without employing electrodes subject to plasma erosion is reviewed. Electrodeless plasma thrusters are potentially more durable than presently deployed thrusters that use electrodes such as gridded ion,Hall thrusters, arcjets and resistojets. Like other plasma thrusters, electrodeless thrusters have the advantage of reduced fuel mass compared to chemical thrusters that produce the same thrust. The status of electrodeless plasma thrusters that could be used in communications satellites and in spacecraft for interplanetary missions is examined. Electrodeless thrusters under development or planned for deployment include devices that use a rotating magnetic field; devices that use a rotating electric field; pulsed inductive devices that exploit the Lorentz force on an induced current loop in a plasma; devices that use radiofrequency fields to heat plasmas and have magnetic nozzles to accelerate the hot plasma and other devices that exploit the Lorentz force. Using metrics of specific impulse and thrust efficiency, we find that the most promising designs are those that use Lorentz forces directly to expel plasma and those that use magnetic nozzles to accelerate plasma.

关键词： spacecraft a review propellant Lorentz thrust rotating radiofrequency erosion presently exploit

Plant photosystem Ⅱ assembly:TrOL2 to the rescue

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Molecular Plant 2023年第11期16卷 1719-1721页

作者： Sujith Puthiyaveetil Steven d.mckenzie department of Biochemistry and Center for Plant Biology Purdue UniversityWest LatayetteIN 47907USA

In one of the most consequential biochemical reactions on earth,a pigment-protein complex known as photosystem Ⅱ(PSⅡ)in photosynthesis extracts electrons,protons,and oxygen from water using energy from ***Ⅱ thereby sustains life on earth by harnessing the potential of two nearly inexhaustible raw materials:sunlight and *** plant PSllis a membrane-embedded *** monomer consists of around 28 unique protein subunits,157 chlorophylls,44 carotenoids,2 pheophytins,a heme,a non-heme iron,two quinones,and a Mn_(4)CaO_(5) cluster(Su et al.,2017;Cao et al.,2018).Within each monomeric complex,20 protein subunits constitute a core(Figure 1A).

关键词： Figure earth thereby

Polyethylene glycol fusion repair of severed rat sciatic nerves reestablishes axonal continuity and reorganizes sensory terminal fields in the spinal cord

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Neural regeneration research 2025年第7期20卷 2095-2107页

作者： Emily A.Hibbard Liwen Zhou Cathy Z.Yang Karthik Venkudusamy Yessenia Montoya Alexa Olivarez George d.Bittner dale r.Sengelaub Program in Neuroscience Indiana UniversityBloomingtonINUSA department of Neuroscience University of Texas at AustinAustinTXUSA

Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically *** used a plasmalemmal fusogen,polyethylene glycol(PEG),to immediately fuse closely apposed open ends of severed proximal and distal axons in rat sciatic *** have previously reported that sciatic nerve axons repaired by PEG-fusion do not undergo Wallerian degeneration,and PEG-fused animals exhibit rapid(within 2–6 weeks)and extensive locomotor ***,our previous report showed that PEG-fusion of severed sciatic motor axons was non-specific,i.e.,spinal motoneurons in PEG-fused animals were found to project to appropriate as well as inappropriate target *** this study,we examined the consequences of PEG-fusion for sensory axons of the sciatic *** adult male and female rats(Sprague–dawley)received either a unilateral single cut or ablation injury to the sciatic nerve and subsequent repair with or without(Negative Control)the application of *** action potentials recorded immediately after PEG-fusion repair confirmed conduction across the injury *** success of PEG-fusion was confirmed through Sciatic Functional Index testing with PEG-fused animals showing improvement in locomotor function beginning at 35 days *** 2–42 days postoperatively,we anterogradely labeled sensory afferents from the dorsal aspect of the hindpaw following bilateral intradermal injection of wheat germ agglutinin conjugated horseradish ***-fusion repair reestablished axonal *** to unoperated animals,labeled sensory afferents ipsilateral to the injury in PEG-fused animals were found in the appropriate area of the dorsal horn,as well as inappropriate mediolateral and rostrocaudal ***,despite having intact peripheral nerves,similar reorganizations of labeled sensory afferents were also observed contralateral to the injury and repa

关键词： axotomy dorsal horn peripheral nerve injury plasticity polyethylene glycol(PEG) sciatic nerve sensory terminals wheat germ agglutinin horseradish peroxidase

Machine Learning Techniques in Predicting Hot deformation Behavior of Metallic Materials

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 713-732页

作者： Petr Opela Josef Walek Jaromír Kopecek department of Metallurgical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—Institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

In engineering practice,it is often necessary to determine functional relationships between dependent and independent *** relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable ***,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely *** study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic *** ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),decision Tree regression(dTr),and Gaussian Process regression(GPr)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon *** the GPr method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis.

关键词： Machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior

Biochemical dissection of STAT3 signaling in amyotrophic lateral sclerosis

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Neural regeneration research 2025年第11期20卷 3229-3230页

作者： Savina Apolloni Nadia d’Ambrosi department of Biology University of Rome Tor VergataRomeItaly

Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative disease characterized by the loss of upper and lower motor neurons,clinically marked by muscle atrophy and *** the clinical course is highly variable,the average time from the onset of symptoms to the need for respiratory support or death is 3-5 *** is the most prevalent motor neuron disease in adults,occurring at a rate of 2 per 100,000 individuals and affecting 5.4 per 100,000 individuals overall.

关键词： STAT3 dissection sclerosis

Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?

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Neural regeneration research 2025年第4期20卷 1092-1093页

作者： danko Jeremic Lydia Jiménez-díaz Juan d.Navarro-López NeuroPhysiology&Behavior Lab University of Castilla-La ManchaBiomedical Research Center(CRIB)School of Medicine of Ciudad RealCiudad RealSpain

Although many causes of Alzheimer’s disease(Ad)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the ***,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in Ad,being able to precede and influence one *** researchers argue that these proteins are mere executors rather than primary causes of ***,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(Jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer additive

remaking a connection:molecular players involved in post-injury synapse formation

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Neural regeneration research 2025年第6期20卷 1719-1720页

作者： diogo Tomé ramiro d.Almeida iBiMEd-Institute of Biomedicine Department of Medical SciencesUniversity of AveiroAveiroPortugal CNC-Center for Neuroscience and Cell Biology University of CoimbraCoimbraPortugal

Functional recovery from central nervous system(CNS)trauma depends not only on axon regeneration or compensatory sprouting of uninjured fibers but also on the ability of newly grown axons to establish functional synapses with appropriate *** several studies have successfully promoted long-distance axonal regeneration in distinct CNS injury models,none of them have resulted in a viable therapeutic approach for patient recovery.A possible reason may be the lack of new synaptogenesis for reestablishing the circuitry lost after ***,we discuss how our understanding of the mechanisms that instruct synapse formation in the injured nervous system may contribute to the design of new strategies to promote functional restoration in traumatic CNS disorders.

关键词： viable injury instru