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Journal of Materials science & Technology 2015年第9期31卷 881-887页

作者： Camelia Matei Ghimbeu Aleksandr I.Egunov andrey s.ryzhikov Valeriy A.Luchnikov Institut de science des Matériaux de Mulhouse

Ensembles of freeze-dried self-rolled polymer micro-scrolls are explored as template media for produc- ing carbon-iron based composites with fibrous morphology. Polymer fibres impregnated with furfuryl alcohol and loaded with Fe2O3 particles, were thermally treated under inert atmosphere at 700 ℃ and subsequently analysed by scanning and transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and nitrogen adsorption. The resulting material has a micro-fibrous mor- phology and is basically composed of metallic Fe^0 and FeO particles, i.e., more than 98 wt% of the carbon/ iron-based composite mass. These particles are held together by amorphous porous carbon foam obtained by in-situ carbonization of the polymer/Fe2O3 composite with evacuation of carbon from the system via COx gases released by carbo-reduction of Fe2O3. The material has significant activity in the reaction of catalytic decomposition of hydrogen peroxide in water solutions.

关键词： Composite materialsPorous carbonPolymersIron particles

Merging bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk sibo Huang Chen shen Almas F.sadreev Yong Li andrey E.Miroshnichenko school of Physics and Electronic sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University school of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Control of light scattering by nanoparticles with optically-induced magnetic responses

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Chinese Physics B 2014年第4期23卷 41-51页

作者：刘伟 andrey E. Miroshnichenko Yuri s. Kivshar College of Optoelectronic science and Engineering National University of Defence Technology Nonlinear Physics Center and Center for Ultrahigh-bandwidth Devices for Optical systems CUDOs) Research School of Physics and EngineeringAustralian National University

Conventional approaches to control and shape the scattering pattems of light generated by different nanostructures are mostly based on engineering of their electric response due to the fact that most metallic nanostructures support only electric resonances in the optical frequency range. Recently, fuelled by the fast development in the fields of metamaterials and plasmonics, artificial optically-induced magnetic responses have been demonstrated for various nanostructures. This kind of response can be employed to provide an extra degree of freedom for the efficient control and shaping of the scattering patterns of nanoparticles and nanoantennas. Here we review the recent progress in this research direction of nanoparticle scattering shaping and control through the interference of both electric and optically-induced magnetic responses. We discuss the magnetic resonances supported by various structures in different spectral regimes, and then summarize the original results on the scattering shaping involving both electric and magnetic responses, based on the interference of both spectrally separated （with different resonant wavelengths） and overlapped dipoles （with the same resonant wavelength）, and also other higher-order modes. Finally, we discuss the scattering control utilizing Fano resonances associated with the magnetic responses.

关键词： optically-induced magnetic response scattering control Mie resonance Fano resonance

Gas-phase hydrogenation influence on defect behavior in titanium-based hydrogen-storage material

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Progress in Natural science:Materials International 2017年第1期27卷 105-111页

作者： Roman s.Laptev Viktor N.Kudiiarov Yuri s.Bordulev andrey A.Mikhaylov andrey M.Lider Department of General Physics Institute of Physics and Technology National Research Tomsk Polytechnic University

Titanium and its alloys are promising materials for hydrogen storage. However, hydrogen penetration accompanies the exploitation of hydrogen storage alloys. In particular, hydrogen penetration and accumulation in titanium alloys changes their mechanical properties. Therefore, the research works of such materials are mainly focused on improving the reversibility of hydrogen absorption-liberation processes, increasing the thermodynamic characteristics of the alloys, and augmenting their hydrogen storage capacity. In the process of hydrogenation-dehydrogenation, the formed defects both significantly reduce hydrogen storage capacity and can also be used to create effective traps for hydrogen. Therefore, the investigation of hydrogen interaction with structural defects in titanium and its alloys is very important. The present work, the hydrogen-induced formation of defects in the alloys of commercially pure titanium under temperature gas-phase hydrogenation（873 K） has studied by positron lifetime spectroscopy and Doppler broadening spectroscopy. Based on the evolution of positron annihilation parameters τ_f, τd, their corresponding intensities If, Idand relative changes of parameters s/s0and W/W0, the peculiarities of hydrogen interaction with titanium lattice defects were investigated in a wide range of hydrogen concentrations from 0.8at% to 32.0at%.

关键词： Titanium Hydrogen Lattice defects Positron annihilation Positron lifetime Doppler broadening

Deep learning as a highly efficient tool for digital signal processing design

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Light(science & Applications) 2024年第11期13卷 2434-2435页

作者： andrey Pryamikov Prokhorov General Physics Institute of the Russian Academy of sciences MoscowRussia

The backpropagation algorithm,the most widely used algorithm for training artificial neural networks,can be effectively applied to the development of digital signal processing schemes in the optical fiber transmission *** signal processing as a deep learning framework can lead to a new highly efficient paradigm for cost-effective digital signal processing designes with low complexity.

关键词： signal digital fiber

Rising complexity of the OAM beam structure as a Way to a higher data capacity

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Light(science & Applications) 2022年第8期11卷 1648-1649页

作者： andrey Pryamikov Prokhorov General Physics Institute of the Russian Academy of sciences MoscowRussia

standard vortex beams carrying different OAM (optical angular momentum) modes can provide independent communication channels for information transmission. However, they are unable to reach the capacity limit of a communication channel due to a rapid divergence of the beams with high values of the OAM order. The solution can be found by using multi-vortex geometric beams.

关键词： OAM communication vortex

Gas fiber lasers may represent a breakthrough in creating powerful radiation sources in the mid-IR

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Light(science & Applications) 2022年第2期11卷 153-155页

作者： andrey Pryamikov Prokhorov General Physics Institute of the Russian Academy of sciences 38 Vavilov streetMoscowRussia

Continuous wave fiber laser created on the basis of silica glass negative curvature hollow core fiber filled with HBr make it possible to obtain efficient narrow linewidth mid-IR emission with a maximum laser power of about 500mW at wavelength of 4200 *** is for the first time that emission from a continuous wave fiber laser have been achieved at a wavelength of 4496 nm with the largest tuning range of 686 nm.

关键词： fiber tuning breakthrough

studies of ultrasonic dehydration efficiency

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2011年第4期12卷 247-254页

作者： Vladimir N. KHMELEV andrey V. sHALUNOV Roman V. BARsUKOV Denis s. ABRAMENKO andrey N. LEBEDEV Biysk Technological Institute (Branch) Altai state Technical University

The aim of this investigation was to define the effectiveness of non-contact drying using ultrasonic vibrations. Disk radiators were used for carrying out experiments, and a special drying chamber was designed to provide resonant amplification of ultrasonic vibrations (from 130 to 150 dB). Drying of ginseng and other vegetables demonstrated that the application of ultrasonic vibrations reduced power inputs by 20% in comparison with convective drying. It also led to a decrease of 6% in final moisture content, if the duration of drying was constant. The level of intensification of ultrasonic drying was high (up to 50 g for 1 kg of drying material), which helped to lower the temperature of the drying agent and improve the quality of the dried products.

关键词： Drying Ultrasound Vibration system Drying chamber Processing (treatment) of agricultural products

Revisiting cerebral endothelial cells in Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurgery University Hospital BonnBonnGermany

Alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： Alzheimer Aβ cerebral

A systematic review of progenitor survival and maturation in Parkinsonian models

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Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&Therapeutics and Galway Neuroscience Center University of GalwayGalwayIreland

stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged froms transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant