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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

Thermal conductivity of systems with a gap in the phonon spectrum

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Chinese Physics B 2018年第7期27卷 424-430页

作者： E Salamatov Udmurt federal research center Ural Branch of the Russian Academy of Sciences

An original theoretical model for describing the low-temperature thermal conductivity in systems with a region of forbidden values （a gap） in the phonon spectrum is proposed. The model is based on new experimental results on the temperature dependence of the phonon diffusion coefficient in nanoceramics and dielectric glasses which showed a similar anomalous behavior of the diffusion coefficient in these systems that may be described under the assumption of a gap in the phonon spectrum. In this paper, the role of the gap in low-temperature behavior of the thermal conductivity, ~＇（T）, is analyzed. The plateau in the temperature dependence of the thermal conductivity is shown to correlate with the position and the width of the gap. The temperature dependence of thermal conductivity of such systems when changing the scat- tering parameters related to various mechanisms is studied. It is found that the umklapp process （U-processes） involving low-frequency short-wavelength phonons below the gap forms the behavior of the temperature dependence of thermal con- ductivity in the plateau region. A comparison of the calculated and experimental results shows considerable possibilities of the model in describing the low-temperature thermal conductivity in glass-like systems.

关键词： phononic band gap phonon diffusion coefficient thermal conductivity glassy crystals

A review on magneto-optical ceramics for Faraday isolators

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Journal of Advanced Ceramics 2023年第5期12卷 873-915页

作者： Lixuan Zhang Dianjun Hu Ilya LSnetkov Stanislav Balabanov Oleg Palashov Jiang Li Transparent Ceramics research center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China center of Materials science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Institute of Applied Physics of the russian academy of sciences Nizhny Novgorod 603950Russia Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod 603950Russia G.G.Devyatykh Institute of Chemistry of High-Purity Substances Russian Academy of SciencesNizhny Novgorod 603951Russia

As a promising magneto-optical(MO)material applied in Faraday isolators,magneto-optical ceramics possess excellent comprehensive properties and have attracted much attention these ***,we review the fabrication and properties of magneto-optical ceramics including garnet,sesquioxide,and A_(2)B_(2)O_(7) *** of the ceramics have been proved to possess applicable performance,while further studies are still needed for most of the magneto-optical *** at the application for isolators,the research status,existing problems,and development trends of magneto-optical ceramics are shown and discussed in this review.

关键词： magneto-optical(MO)ceramics Faraday isolators optical quality thermo-optical effects

Geophysical criterion of pre-outburst coal outsqueezing from the face space into the working

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International Journal of Mining science and Technology 2019年第3期29卷 499-506页

作者： Alexander Shadrin Yuliya Diyuk federal State Budget Scientific Institution The Federal Research Center of Coal and Coal Chemistry of Siberian Branch of the Russian Academy of Sciences

The initial process of coal and gas sudden outburst is studied in the article when under the influence of rock and gas pressure the part of a coal seam layer(a coal section)is squeezed out from the mouth of the future outburst cavity in a jump-like manner into the ***-mechanical criterion for a part of a coal seam layer outsqueezing in the form of the relation of active(squeezing out)and passive(preventing the outsqueezing)forces is defined in the *** on it,the geophysical criterion is defined by expressing basic physical parameters through geo-physical ones:the current stress is defined by spectral-acoustic method through the ratio of high frequency and low-frequency components of an acoustic signal,which is generated into a face working space by the mining equipment operating in the face;in-situ gas pressure is defined by gas analytical method by the concentration of methane in the atmosphere of the working;the strength of the most broken coal layer is defined by a strength measuring device(a device for measuring the depth of a steal cone punched into the coal by a spring mechanism).This paper studies the influence of acoustic,strength and filtrating and collecting properties of a face working space on the limit value of an obtained geophysical criterion of pre-outburst squeezing of a coal‘‘plug”out of the mouth of the future outburst cavity into the working.

关键词： Block-like structure Criterion of a coal section outsqueezing Spectral-acoustic method Stress condition Coal strength property In-situ gas pressure Aero and gas control equipment Methane concentration

Two-body nonleptonic decays of the heavy mesons in the factorization approach

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Frontiers of physics 2023年第6期18卷 107-126页

作者： Shuo-Ying Yu Xian-Wei Kang V.O.Galkin Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China federal research center“computer science and control” Russian Academy of SciencesVavilov Street 40119333 MoscowRussia

In the framework of the factorization approach we calculate the branching fractions of 100 two-body nonleptonic decay channels in total,including 44 channels of the charm meson decays and 56 channels of the bottom meson *** charm meson decays,we test and confirm the previous observation that taking the limit for the number of colors N→∞significantly improves theoretical *** bottom meson decays,the penguin contributions are included in *** an essential input,we employ the weak decay form factors obtained in the framework of the relativistic quark model based on the quasi-potential *** form factors have well been tested by calculating observables in the semileptonic D and B meson decays and confronting obtained results with experimental *** general,the predictions for the nonleptonic decay branching fractions are ***,for a quantitative calculation it is necessary to account for a more subtle effects of the final-state interaction.

关键词： form factor quark model nonleptonic decay factorization method

Ignition of nanothermites by a laser diode pulse

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Defence Technology（防务技术） 2022年第2期18卷 194-204页

作者： Alexander Yu.Dolgoborodov Vladimir G.Kirilenko Michael A.Brazhnikov Leonid I.Grishin Michael L.Kuskov Georgii E.Valyano Joint Institute for High Temperatures Russian Academy of SciencesRussia N.Semenov federal research center for Chemical Physics Russian Academy of SciencesRussia National research Nuclear University MEPhI Moscow Russia

Experimental investigation has been carried out for laser ignition and combustion of nanothermites based on aluminum and oxides of copper,bismuth and *** mixing of nanosized powders was used to produce *** thermite ignition,initiating laser pulse with a maximum intensity of 770 W/cm2 was generated by a laser diode with a wavelength of 808 *** ignition delay times,the minimum initiation energy density,and the average burning rate at various thermite densities and mass fractions of components were determined by recording the emission of radiation of the reaction products using a multichannel pyrometer jointly with a high-speed video *** effect of adding carbon black on the threshold parameters of a laser pulse was also *** on the obtained results,certain assumptions were put forward with regard to the mechanism of nanothermites’ignition by laser radiation and their *** particular,the assumptions were made on the two-stage process of the reaction initiation and jet burning mechanism of porous nanothermites.

关键词： Nanothermites Laser ignition Burning rate Ignition delay

Heat Capacity and Thermal Expansion of Water and Helium

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Journal of Thermal science 2017年第2期26卷 125-131页

作者： N.M.Putintsev D.N.Putintsev Department of Chemistry Murmansk State Technical UniversitySt.Sport 13183010MurmanskRussia Institute for Systems Analysis Federal Research Center《Computer Science and Controb》of the Russian Academy of SciencesPr.60-Letiya Oktyabrya9117312MoscowRussia

Original expressions for heat capacity CV and its components, vibrational and configurational components of thermal expansion coefficient were established. The values of CV, Cvib, Cconf, Cvib and Cconf for water and h... 详细信息

关键词： heat capacity thermal expansion coefficient isothermal compressibility vibrational input configurational input water helium 4.

Reactive SPS of Al_(2)O_(3)–RE:YAG(RE=Ce;Ce+Gd)composite ceramic phosphors

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Journal of Advanced Ceramics 2023年第5期12卷 1015-1032页

作者： Denis Yu.Kosyanov Anastasia A.Vornovskikh Oleg O.Shichalin Evgeniy K.Papynov Anton A.Belov Aleksandra A.Kosianova Aleksandr N.Fedorets Andrei A.Leonov Alexey P.Zavjalov Sergey A.Tikhonov Yanbin Wang Ziqiu Cheng Xin Liu Jiang Li Far Eastern federal University Vladivostok 690922Russia Institute of Automation and control Processes Far Eastern Branch of the Russian Academy of SciencesVladivostok 690041Russia Laboratory of Methods of Synchrotron Radiation Institute of Solid State Chemistry and MechanochemistrySiberian Branch of the Russian Academy of SciencesNovosibirsk 630128Russia Kamchatka Branch of Geophysical Survey of the russian academy of sciences Petropavlovsk-Kamchatsky 683006Russia Key Laboratory of Transparent Opto-functional Inorganic Materials Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China center of Materials science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Ultrafine-grained Al_(2)O_(3)–rare earth:yttrium aluminium garnet(Al_(2)O_(3)–RE:YAG)(RE=Ce;Ce+Gd)composite ceramics were obtained for the first time by reactive spark plasma sintering(SPS)using commercially available initial oxide *** effect of key sintering parameters(temperature,dwell time,and external pressure(P_(load)))on densification peculiarities,structural-phase states,and luminescent properties of composites was studied *** in phase formation and densification between Ce-doped and Ce,Gd-codoped systems were *** of reactive SPS,at which there is partial melting with the formation of near-eutectic zones of the Al_(2)O_(3)–YAG system/coexistence of several variations of the YAG-type phase,were *** corundum–garnet biphasic ceramics with an optimal balance between microstructural and luminescence performance were synthesized at 1425℃/30 min/30–60 *** external quantum efficiency(EQE)of the phosphor converters reached 80.7%and 72%with close lifetime of~63.8 ns,similar to those of commercial Ce:YAG materials,which is promising for further applications in the field of high-power white light-emitting diodes(WLEDs)and laser diodes(LDs).

关键词： alumina–Ce^(3+)-doped yttrium aluminium garnet(Al_(2)O_(3)–Ce:YAG)ceramic phosphors reactive spark plasma sintering(SPS) structural-phase states microstructure luminescence performance

Evaluation of the energy efficiency of rotary percussive drilling using dimensionless energy index

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1486-1500页

作者： V.N.Oparin V.N.Karpov V.V.Timonin A.I.Konurin Chinakal Institute of Mining Siberian BranchRussian Academy of SciencesKrasnyi Prospect 54Novosibirsk630091Russia

This paper sets forth a geomechanics framework for assessing the energy efficiency of rotary percussive drilling using the energy criterion, which has been proposed by Victor Oparin for volumetric destruction of high-stress rocks having nonuniform physico-mechanical properties. We review the long-term research and development in the specified area of science and technology, including research and development projects implemented at the Institute of Mining, Siberian Branch of the russian academy of sciences. A new modified expression of Oparin’s dimensionless energy criterion of volumetric rock destruction k is introduced. The range of in situ values is determined for the energy criterion of volumetric rock destruction at the optimized energy efficiency of rotary percussive drilling. The temporospatial intervals of geotechnical monitoring are found to control pneumatic drilling energy efficiency at subsoil use objects in Russia. The integrated experimental, theoretical and geotechnical approach to the comprehensive investigation of real-time processes of rock fracture in rotary percussive drilling using the energy concept possesses the necessary geomechanical performance-and-technology potential to create the next level geotechnical monitoring of drilling systems for various purposes, including determination of physico-mechanical properties and the stress-strain analysis of rock mass in full-scale drilling.

关键词： Rotary percussive drilling Geotechnical monitoring Drilling machine Energy criterion Energy efficiency