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NH_(3)laser THz emission under optical pumping by“long”(~100μs)CO_(2)laser pulses

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Chinese Optics Letters 2023年第2期21卷 133-137页

作者： Andrey Alekseevich Ionin Igor Olegovich Kinyaevskiy Yuri mikhailovich Klimachev Andrey Yurievich Kozlov Darya Ivanovna Kormashova Andrey Alexandrovich Kotkov Yury Alekseevich mityagin sergey Alexandrovich Savinov Adilya maratovna Sagitova Dmitry Vasilievich Sinitsyn maxim Vladimirovich Ionin P.N.Lebedev Physical Institute of the Russian Academy of Sciences Moscow 119991Russia

Terahertz(THz)NH_(3) lasing with optical pumping by electron-beam-sustained discharge“long”(~100μs)CO_(2) laser pulses was *** NH3laser emission pulses and the“long”pulses of the CO_(2) pump laser were simultaneously measured with nanosecond response *** NH3 lasing duration and its delay with respect to the pump pulse were measured for various CO_(2) laser pulse *** the CO_(2) laser pump line 9R(30),three wavelengths of 67.2,83.8,and 88.9μm were *** the CO_(2) laser pump line 9R(16),only a single NH3 laser line with a wavelength of 90.4μm was detected.

关键词： NH3 laser CO_(2)laser terahertz emission nanosecond response time

Impulse magnetic stimulation facilitates synaptic regeneration in rats following sciatic nerve injury

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Neural Regeneration Research 2012年第17期7卷 1299-1303页

作者： sergey A.Zhivolupov miroslav m.Odinak Nariman A.Rashidov Ludmila S.Onischenko Igor N.Samartsev Anton A.Jurin Department of Neurology Military-Medical AcademySaint-Petersburg194044Lesnoy prospect 2Russian Federation

The current studies describing magnetic stimulation for treatment of nervous system diseases mainly focus on transcranial magnetic stimulation and rarely focus on spinal cord magnetic stimulation. Spinal cord magnetic stimulation has been confirmed to promote neural plasticity after injuries of spinal cord, brain and peripheral nerve. To evaluate the effects of impulse magnetic stimulation of the spinal cord on peripheral nerve regneration, we compressed a 3 mm segment located in the middle third of the hip using a sterilized artery forceps to induce ischemia. Then, all animals underwent impulse magnetic stimulation of the lumbar portion of spinal crod and spinal nerve roots daily for 1 month. Electron microscopy results showed that in and below the injuryed segment, the inflammation and demyelination of neural tissue were alleviated, apoptotic cells were reduced, and injured Schwann cells and myelin fibers were repaired. These findings suggest that high-frequency impulse magnetic stimulation of spinal cord and corresponding spinal nerve roots promotes synaptic regeneration following sciatic nerve injury.

关键词： impulse magnetic stimulation experimental neuropathy sciatic nerve lesion neuroplasticity neuralregeneration

Revolving scheme for solving a cascade of Abel equations in dynamics of planar satellite rotation

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Theoretical & Applied mechanics Letters 2017年第3期7卷 175-178页

作者： sergey V. Ershkov Sternberg Astronomical Institute M.V. Lomonosov's Moscow State University Moscow 119992 Russia

The main objective for this research was the analytical exploration of the dynamics of planar satellite rotation during the motion of an elliptical orbit around a planet. First, we revisit the results of J. Wisdom et al. （1984）, in which, by the elegant change of variables （considering the true anomaly f as the independent variable）, the governing equation of satellite rotation takes the form of an Abel ordinary differential equation （ODE） of the second kind, a sort of generalization of the Riccati ODE. We note that due to the special character of solutions of a Riccati-type ODE, there exists the possibility of sudden jumping in the magnitude of the solution at some moment of time. In the physical sense, this jumping of the Riccati-type solutions of the governing ODE could be associated with the effect of sudden acceleration[deceleration in the satellite rotation around the chosen principle axis at a definite moment of parametric time. This means that there exists not only a chaotic satellite rotation regime （as per the results of J. Wisdom et al. （1984））, but a kind of gradient catastrophe （Arnold, 1992） could occur during the satellite rotation process. We especially note that if a gradient catastrophe could occur, this does not mean that it must occur： such a possibility depends on the initial conditions. In addition, we obtained asymptotical solutions that manifest a quasi-periodic character even with the strong simplifying assumptions e → 0, p -- 1, which reduce the governing equation of J. Wisdom et al. （1984） to a kind of Beletskii＇s equation.

关键词： Beletskii's equation Satellite rotation Abel ODE Gradient catastrophe

Simulation of thermal processes in metamaterial millimeter-wave to infrared converter for millimeter-wave imager

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International Journal of modeling, Simulation, and Scientific Computing 2014年第S1期5卷 120-128页

作者： Peter S.Zagubisalo Andrey G.Paulish sergey A.Kuznetsov Novosibirsk Branch of the Institute of Semiconductor Physics Siberian Branch of Russian Academy of Sciences 2/1 pr.Akademika LavrentyevaNovosibirsk 630090Russian Federation Novosibirsk State University 2 ul.PirogovaNovosibirsk 630090Russian Federation

The main characteristics of millimeter-wave(mm-wave)image detector were simulated by means of accurate numerical modeling of thermophysical processes in a metamaterial mm-to-IR *** converter represents a multilayer structure consisting of an ultra thin resonant metamaterial absorber and a perfect emissive *** absorber consists of a dielectric self-supporting film that is metallized from both sides.A micropattern is fabricated from one *** absorption of the mm waves induces the converter heating that yields enhancement of IR emission from the emissive *** emission is detected by IR *** this contribution an accurate numerical model for simulation of the thermal processes in the converter structure was created by using COmSOL multiphysics *** simulation results are in a good agreement with experimental results that validates the *** simulation shows that the real-time operation is provided for the converter thickness less than 3µm and time response can be improved by decreasing of the converter *** energy conversion efficiency of mm waves into IR radiation is over 80%.The converter temperature increase is a linear function of a mm-wave radiation power within three orders of the dynamic *** blooming effect and ways of its reducing are also *** model allows us to choose the ways of converter structure optimization and improvement of image detector parameters.

关键词： metamaterials subterahertz waves terahertz waves millimeter waves highimpedance surface ultra-thin absorber focal plane array detector bolometric detectors thermodynamic modeling optical readout system

Characterization and Electrochemical Properties of Nanostructured Zr-Doped Anatase TiO_2 Tubes Synthesized by Sol–Gel Template Route

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Journal of materials Science & Technology 2017年第6期33卷 527-534页

作者： Denis P.Opra sergey V.Gnedenkov sergey L.Sinebryukhov Elena I.Voit Alexander A.Sokolov Evgeny B.modin Anatoly B.Podgorbunsky Yury V.Sushkov Veniamin V.Zheleznov Institute of Chemistry Far Eastern Branch of Russian Academy of Sciences Far Eastern Federal University National Research Centre "Kurchatov Institute"

A series of nanostructured Zr-doped anatase TiO_2 tubes with the Zr/Ti molar ratio of 0.01, 0.02, 0.03, and0.09 were prepared by a sol–gel technology on a carbon fiber template. The electrochemical performance of Zr-doped anatase TiO_2 as anodes for rechargeable lithium batteries was investigated and compared with undoped titania. Tests represented that after 35-fold charge/discharge cycling at C/10 the reversible capacity of Zr-doped titania（Zr/Ti = 0.03） reaches 135 m A h g^（-1）, while the capacity of undoped titania（Zr/Ti = 0） yielded only 50 m A h g^（-1）. Based on the results of the physicochemical investigation, three reasons of improving electrochemical performance of Zr-doped titania were suggested. According to the scanning electron microscopy and transmission electron microscopy, Zr^（4＋） doping induces a decrease in nanoparticle size, which facilitates the Li＋diffusion. The Raman investigations show the more open structure of Zr-doped TiO_2 as compared to undoped titania due to changing of the unit cell parameters, that significantly affects on the reversibility of the insertion/extraction process. The electrochemical impedance spectroscopy results indicate that substitution of Zr^（4＋） for Ti^（4＋） into anatase TiO_2 has favorable effects on the conductivity.

关键词： Li-ion batteries Anatase titania Nanostructured materials Sol–gel template process Doping Electrochemical performance

Identification of genes involved in the formation of soluble dietary fiber in winter rye grain and their expression in cultivars with different viscosities of wholemeal water extract

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The Crop Journal 2022年第2期10卷 532-549页

作者： Liudmila V.Kozlova Alsu R.Nazipova Oleg V.Gorshkov Liliya F.Gilmullina Olga V.Sautkina Natalia V.Petrova Oksana I.Trofimova sergey N.Ponomarev mira L Ponomareva Tatyana A.Gorshkova Kazan Institute of Biochemistry and Biophysics Federal Research CenterKazan Scientific Center of the Russian Academy of Sciences420111 KazanRussia Tatar Scientific Research Institute of Agriculture Federal Research CenterKazan Scientific Center of the Russian Academy of Sciences420059 KazanRussia

The grain of rye(Secale cereale L.) used for baking contains a large amount of non-starch polysaccharides,making it an excellent component of functional foods. But rye grain intended for alcohol production and forage use should have a reduced content of these polysaccharides. A comprehensive parameter that can predict the best field of application for winter rye grain is the viscosity of its wholemeal water ***, our understanding of the genetic background underlying this key trait and associated features of rye grain is poor. By analyzing six Russian winter rye cultivars, we identified the most contrasting forms and characterized the peculiarities of their water-soluble carbohydrates capable of influencing the viscosity of water extracts. Then, using phylogenetic and transcriptomic analyses, we identified in the rye genome many genes encoding putative glycosyltransferases and glycosylhydrolases responsible for the synthesis and degradation of arabinoxylans, mixed-linkage glucans, cellulose, and some other polysaccharides. We determined the dynamics of m RNA abundance for these genes at three stages of kernel development. Comparisons of gene expression levels in two contrasting cultivars revealed specific members of multigene families that may serve as promising targets for manipulating non-starch polysaccharide content in rye grain. High-viscosity cultivars were characterized by up-regulation of many glycosyltransferases involved in the biosynthesis of arabinoxylans and other cell-wall polysaccharides,whereas low-viscosity cultivars showed up-regulation of several genes encoding polysaccharidedegrading enzymes.

关键词： Rye(Secale cereale) Kernel development Arabinoxylan mixed-linkage glucan Viscosity

New insights into substrate folding preference of plant OSCs

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Science Bulletin 2016年第18期61卷 1407-1412页

作者： Yongshuo ma Yuan Zhou sergey Ovchinnikov Per Jr.Greisen Sanwen Huang Yi Shang Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture Sino-Dutch Joint Laboratory of Horticultural Genomics Department of Biochemistry University of Washington Department of modelling Novo Nordisk A/S 2760 Ml?vDenmark Agricultural Genomic Institute at Shenzhen Chinese Academy of Agricultural Sciences

Sterols and triterpenes are structurally diverse bioactive molecules generated through cyclization of linear2,3-oxidosqualene. Based on carbocationic intermediates generated during initial substrate preorganization step,oxidosqualene cyclases(OSCs) are roughly segregated into protosteryl cation group that mainly catalyzes tetracyclic products and dammarenyl cation group which mostly generates pentacyclic products. However, in contrast to well-studied cascade of ring-forming reactions, little is known about the mechanism underlying the initial substrate folding process. Previously, we have identified a cucurbitadienol synthase(Bi) and its null allele bi(C393Y)from cucumber. By integration of homology modeling,residue coevolution and site-directed mutagenesis, we discover that four covarying amino acids including C393 constitute a dynamic domain that may be involved in substrate folding process for Bi. We also reveal a group of co-conserved residues that closely associated with the segregation of plant OSCs. These residues may act collaboratively in choice of specific substrate folding intermediate for OSCs. Thus, our findings open a door to engineer plant OSCs from four-ringed skeleton catalysts into five-ringed producer.

关键词：折叠过程有机基板植物偏好生物活性分子三萜类化合物无效等位基因离子基团

Development of CO2 Selective Poly（Ethylene Oxide）-Based membranes： From Laboratory to Pilot Plant Scale

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Engineering 2017年第4期3卷 485-493页

作者： Torsten Brinkmann Jelena Lilleparg Heiko Notzke Jan Pohlmann sergey Shishatskiy Jan Wind Thorsten Wolff Institute of Polymer Research Helmholtz-Zentrum Geesthacht Geesthacht 21502 Germany

气体膜分离法是从气流中分离二氧化碳(CO_2)的最有前途的技术之一。例如,采用该技术对燃烧过程中的烟气进行处理,以达到CO_2捕集和封存的目的。聚环氧乙烷嵌段共聚物能够很好地应用于膜分离技术,如Pebax~?或Poly Active^(Tm)。本文采用P... 详细信息

气体膜分离法是从气流中分离二氧化碳(CO_2)的最有前途的技术之一。例如,采用该技术对燃烧过程中的烟气进行处理,以达到CO_2捕集和封存的目的。聚环氧乙烷嵌段共聚物能够很好地应用于膜分离技术,如Pebax~?或Poly Active^(Tm)。本文采用Poly Active^(Tm)作为复合薄膜的选择层。在环境温度下,当CO_2/N_2选择性超过55时,这种薄膜的CO_2渗透率高达4 m^3(STP)·m^(–2)·h^(–1)·bar^(–1)(注:1 bar=105 Pa)。这种薄膜可以按照中试规模进行生产放大,而且可以设计成不同的平面膜组件。采用单一气体渗透数据作为唯一的实验输入而开发出的仿真工具可以准确预测这种膜组件的性能。在不同的中试研究中,我们利用烟气和沼气作为原料气流,反复检测这些膜和膜组件的性能。Poly Active^(Tm)在检测中显示出了稳定的分离性能,表明Poly Active^(Tm)非常适用于作为膜材料进行工业规模气体处理。

关键词：气体渗透薄膜复合膜 CO2分离 CCS 沼气处理膜组件

A Review of Arctic-Subarctic Ocean Linkages: Past Changes, mechanisms, and Future Projections

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Ocean-Land-Atmosphere Research 2023年第1期2卷 134-172页

作者： Qiang Wang Qi Shu Shizhu Wang Agnieszka Beszczynska-moeller sergey Danilov Laura de Steur Thomas W.N.Haine michael Karcher Craig m.Lee Paul G.myers Igor V.Polyakov Christine Provost Øystein Skagseth Gunnar Spreen Rebecca Woodgate Alfred Wegener Institute Helmholtz Centre for Polar and marine Research(AWI) BremerhavenGermany First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdaoPeople’s Republic of China Shandong Key Laboratory of marine Science and Numerical modeling QingdaoPeople’s Republic of China Institute of Oceanology Polish Academy of SciencesSopotPoland Department of mathematics and Logistics Jacobs UniversityBremenGermany Norwegian Polar Institute Fram CentreTromsøNorway Earth&Planetary Sciences The Johns Hopkins UniversityBaltimoreMDUSA .8Ocean Atmosphere Systems GmbH HamburgGermany Applied Physics Laboratory University of WashingtonSeattleWAUSA. Department of Earth and Atmospheric Sciences University of AlbertaEdmontonABCanada. International Arctic Research Center and College of Natural Science and mathematics University of Alaska FairbanksFairbanksAKUSA. Finnish meteorological Institute HelsinkiFinland. Laboratoire LOCEAN-IPSL Sorbonne Université(UPMCUniversity Paris 6)CNRSIRDMNHNParisFrance. Institute of marine Research and Bjerknes Centre of Climate Research BergenNorway. Institute of Environmental Physics University of BremenBremenGermany.

Arctic Ocean gateway fluxes play a crucial role in linking the Arctic with the global ocean and affecting climate and marine *** reviewed past studies on Arctic-Subarctic ocean linkages and examined their changes and driving *** review highlights that radical changes occurred in the inflows and outflows of the Arctic Ocean during the ***,the Pacific inflow temperature in the Bering Strait and Atlantic inflow temperature in the Fram Strait hit record highs,while the Pacific inflow salinity in the Bering Strait and Arctic outflow salinity in the Davis and Fram straits hit record *** the ocean heat convergence from lower latitudes to the Arctic and the hydrological cycle connecting the Arctic with Subarctic seas were stronger in 2000-2020 than in ***6 models project a continuing increase in poleward ocean heat convergence in the 21st century,mainly due to warming of inflow *** also predict an increase in freshwater input to the Arctic Ocean,with the largest increase in freshwater export expected to occur in the Fram Strait due to both increased ocean volume export and decreased *** Strait sea ice volume export hit a record low in the 2010s and is projected to continue to decrease along with Arctic sea ice *** quantitatively attribute the variability of the volume,heat,and freshwater transports in the Arctic gateways to forcing within and outside the Arctic based on dedicated numerical simulations and emphasize the importance of both origins in driving the variability.

关键词： Arctic ocean Strait