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E-beam manipulation of Si atoms on graphene edges with an aberration-corrected scanning transmission electron microscope

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Nano Research 2018年第12期11卷 6217-6226页

作者： Ondrej Dyck Songkil Kim sergei V.Kalinin Stephen Jesse Center for Nanophase Materials Science Oak Ridge National LaboratoryOak RidgeTN 37830USA Institute for Functional Imaging of Materials Oak Ridge National LaboratoryOak RidgeTN 37830USA School of Mechanical Engineering Pusan National UniversityBusan 46241Republic of Korea

The burgeoning field of atomic-level material control holds great promise for future breakthroughs in quantum and memristive device manufacture and fundamental studies of atomic-scale chemistry. Realization of atom-by-atom control of matter represents a complex and ongoing challenge. Here, we explore the feasibility of controllable motion of dopant Si atoms at the edges of graphene via the sub-atomically focused electron beam in a scanning transmission electron microscope. We demonstrate that the graphene edges can be cleaned of Si atoms and then subsequently replenished from nearby source material. It is also shown how Si edge atoms may be “pushed” from the edge of a small hole into the bulk of the graphene lattice and from the bulk of the lattice back to the edge. This is accomplished through sputtering of the edge of the graphene lattice to bury or uncover Si dopant atoms. Finally, we demonstrate e-beam mediated hole healing and incorporation of dopant atoms. These experiments form an initial step toward general atomic-scale material control.

关键词： atomic manipulation graphene scanning transmission electron microscopy edge passivation silicon dopant electron beam dynamics

Calcium-permeable AMPA receptors:an underestimated pharmacological target for the therapy of brain pathologies

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Neural Regeneration Research 2023年第12期18卷 2669-2670页

作者： sergei G.Gaidin Artem M.Kosenkov Federal Research Center“Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences” Institute of Cell Biophysics of the Russian Academy of SciencesPushchinoRussia

Excitotoxicity resulting from the accumulation of extracellular glutamate(the main excitatory neurotransmitter in the brain)is one of the main causes of neuronal death in various brain pathologies,including traumatic brain injury,epilepsy,stroke,and a number of neurodegenerative diseases such as Parkinson's and Alzheimer's diseases.

关键词： epilepsy diseases Alzheimer

Stable optical vortices in nonlinear multicore fibers

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Light(Science & Applications) 2015年第1期4卷 245-250页

作者： Ljupco Hadzievski Aleksandra Maluckov Alexander MRubenchik sergei Turitsyn Vinca Institute of Nuclear Sciences University of BelgradeP.O.Box 52211001 BelgradeSerbia Lawrence Livermore National Laboratory LivermoreCalifornia 94550USA Aston Institute of Photonic Technologies Aston UniversityB47ET BirminghamUK Laboratory of Nonlinear Photonics Novosibirsk State UniversityNovosibirsk630090Russia

The multicore fiber(MCF)is a physical system of high practical *** addition to standard exploitation,MCFs may support discrete vortices that carry orbital angular momentum suitable for spatial-division multiplexing in high-capacity fiber-optic communication *** discrete vortices may also be attractive for high-power laser *** present the conditions of existence,stability,and coherent propagation of such optical vortices for two practical MCF *** optimization,we found stable discrete vortices that were capable of transferring high coherent power through the MCF.

关键词： coherent energy propagation multicore fibers nonlinear vortices

Large scale hybrid Monte Carlo simulations for structure and property prediction

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npj Computational Materials 2018年第1期4卷 1-7页

作者： sergei Prokhorenko Kruz Kalke Yousra Nahas Laurent Bellaiche Physics Department and Institute for Nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA

The Monte Carlo method is one of the first and most widely used algorithms in modern computational *** condensed matter physics,the particularly popular flavor of this technique is the Metropolis Monte Carlo *** being incredibly robust and easy to implement,the Metropolis sampling is not well-suited for situations where energy and force evaluations are computationally *** search for a more efficient technique,we here explore the performance of Hybrid Monte Carlo sampling,an algorithm widely used in quantum electrodynamics,as a structure prediction scheme for systems with long-range *** results show that the Hybrid Monte Carlo algorithm stands out as an excellent computational scheme that can not only significantly outperform the Metropolis sampling but also complement molecular dynamics in materials science applications,while allowing ultra-large-scale simulations of systems containing millions of particles.

关键词： prediction property scheme

Learning surface molecular structures via machine vision

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npj Computational Materials 2017年第1期3卷 194-202页

作者： Maxim Ziatdinov Artem Maksov sergei V.Kalinin Institute for Functional Imaging of Materials Oak Ridge National LaboratoryOak RidgeTN 37831USA Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Bredesen Center for Interdisciplinary Research University of TennesseeKnoxvilleTN 37996USA

Recent advances in high resolution scanning transmission electron and scanning probe microscopies have allowed researchers to perform measurements of materials structural parameters and functional properties in real space with a picometre *** many technologically relevant atomic and/or molecular systems,however,the information of interest is distributed spatially in a non-uniform manner and may have a complex multi-dimensional *** of the critical issues,therefore,lies in being able to accurately identify(‘read out’)all the individual building blocks in different atomic/molecular architectures,as well as more complex patterns that these blocks may form,on a scale of hundreds and thousands of individual atomic/molecular *** we employ machine vision to read and recognize complex molecular assemblies on ***,we combine Markov random field model and convolutional neural networks to classify structural and rotational states of all individual building blocks in molecular assembly on the metallic surface visualized in high-resolution scanning tunneling microscopy *** show how the obtained full decoding of the system allows us to directly construct a pair density function—a centerpiece in analysis of disorderproperty relationship paradigm—as well as to analyze spatial correlations between multiple order parameters at the nanoscale,and elucidate reaction pathway involving molecular conformation *** method represents a significant shift in our way of analyzing atomic and/or molecular resolved microscopic images and can be applied to variety of other microscopic measurements of structural,electronic,and magnetic orders in different condensed matter systems.

关键词： allowed classify spatially

Evolution of structure and physical properties in Al-substituted Ba-hexaferrites

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Chinese Physics B 2016年第1期25卷 706-711页

作者： Alex Trukhanov Larisa Panina sergei Trukhanov Vitalii Turchenko Mohamed Salem National University of Science and Technology MISiS 119049MoscowLeninsky Prospckt4Russia SSPA Scientific and Practical Materials Research Centre of NAS of Belarus 220072 RBMinsk19 P.Brovki Str.Russia Joint Institute for Nuclear Research 141980Dubna6 Joliot-Curie StreetRussia

The investigations of the crystal and magnetic structures of the BaFe12_xAlxO19 （x = 0.1-1.2） solid solutions have been performed with powder neutron diffractometry. Magnetic properties of the BaFe12_xAlxOt9 （x = 0.1-1.2） solid solutions have been measured by vibration sample magnetometry at different temperatures under different magnetic fields. The atomic coordinates and lattice parameters have been Rietveld refined. The invar effect is observed in low temperature range （from 4.2 K to 150 K）. It is explained by the thermal oscillation anharmonicity of atoms. The increase of microstress with decreasing temperature is found from Rietveld refinement. The Curie temperature and the change of total magnetic moment per formula unit are found for all compositions of the BaFet2_xAlxO19 （x = 0.1-1.2） solid solutions. The magnetic structure model is proposed. The most likely reasons and the mechanism of magnetic structure formation are discussed.

关键词： barium hexaferrites neutron diffraction crystal and magnetic structures

The role of GRP81 lactate receptor in synaptic transmission regulation: does it enhance endocytosis?

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Neural Regeneration Research 2022年第12期17卷 2657-2658页

作者： sergei V.Fedorovich Tatsiana V.Waseem Department of Biochemistry Belarusian State UniversityMinskBelarus Independent researcher MinskBelarus

The brain is an expensive tissue in terms of energy *** composes about 2%of body mass and consumes about 20%of all oxygen and calories(Fedorovich and Waseem,2018).For neurons,glucose is the primary energy substrate,although they are able to use ketone bodies,pyruvate and lactate(Fedorovich and Waseem,2018).All these compounds can be metabolized directly in the Krebs cycle,bypassing ***,they are often termed non-glycolytic energy *** of all potential non-glycolytic substrates,lactate is the most physiological(Magistretti and Allaman,2018).Ketone bodies could reach concentrations in blood plasma and cerebrospinal fluid which are sufficient to meet metabolic demands of neurons only under specific non-physiological conditions,e.g.,ketogenic diet and starvation,or during *** contrast,the normal plasma level of lactate is about 1.5 mM and can reach 20 mM during intensive physical exercise.

关键词： ketone glycol cycle

On the liquid-phase technology of carbon fiber/aluminum matrix composites

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International Journal of Minerals,Metallurgy and Materials 2019年第12期26卷 1578-1584页

作者： sergei Galyshev Andrew Gomzin Rida Gallyamova Igor Khodos Fanil Musin Institute of Solid State Physics of Russian Academy of Sciences Chernogolovka 142432Russia Ufa State Aviation Technical University Ufa 450000Russia Ufa Chemistry Institute of Russian Academy of Sciences Ufa 450000Russia Institute of Microelectronics Technology and High Purity Materials Russian Academy of Sciences Chernogolovka 142432Russia

The main problems with the liquid-phase technology of carbon fiber/aluminum matrix composites include poor wetting of the fiber with liquid aluminum and formation of aluminum carbide on the fibers’*** paper aims to solve these *** theoretical and experimental dependence of porosity on the applied pressure were *** possibility of obtaining a carbon fiber/aluminum matrix composite wire with a strength value of about 1500 MPa was *** correlation among the strength of the carbon fiber reinforced aluminum matrix composite,the fracture surface,and the degradation of the carbon fiber surface was discussed.

关键词： carbon fiber/aluminum matrix composite liquid-phase fabrication infiltration pressure composite porosity composite wire ultrasonic

Applications of physical methods in estimation of soil biota and soil organic matter

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Soil Ecology Letters 2020年第3期2卷 165-175页

作者： Chagovetc sergei Shenglei Fu Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions Ministry of EducationCollege of Environment and PlanningHenan UniversityKaifeng 475004China Henan Key Laboratory of Integrated Air Pollution Control and Ecological Security Henan UniversityKaifeng 475004China

Soil biota is the living component of soil organic matter(SOM),and plays a key role in the decomposition of *** soil biota and SOM are indicators of soil fertility and soil ***,they both are sensitive to soil *** researchers developed various technologies to detect soil biota and SOM,they are mostly destructive and cause disturbance to soil,which may not reflect the actual situation of soil biota and ***,here we mostly focused on the non-destructive physical methods for estimating soil biota and SOM and discussed their advantages and *** methods include but not limited to acoustic detection,radio frequency identification,radioactive tagging,hyperspectral sensing and electron energy loss *** addition,we pointed out the current research problems and the potential research directions for applications of physical methods in estimation of soil biota and SOM.

关键词： Soil organic matter Soil biota Advanced method Acoustic method Spectroscopy Tagging