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Impact of air drought on photosynthesis efficiency of the Siberian crabapple(Malus baccata L. Borkh.) in the forest-steppe zone of Transbaikalia, Russia

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Journal of Arid Land 2019年第2期11卷 255-266页

作者： alexandr rudikovskii Elena RUDIKOVSKAYA Lyubov DUDAREVA Siberian Institute of Plant Physiology and Biochemistry of Siberian Branch Russian Academy of Sciences

The adaption of photosynthesis, being a key metabolic process, plays an important role in plant resistance to air drought. In this study, the Siberian crabapple(Malus baccata L. Borkh.) in the forest-steppe zone of Transbaikalia region, Russia, was subjected to air drought stress and its photosynthesis characteristics were analyzed. The results show that air drought and sufficient soil moisture supply lead to the decrease in the total chlorophyll(Chl) content, while the ratio of Chls to carotenoids is constant in the Siberian crabapple tree. The function of photosystem II(PS-II) in the crabapple trees is characterized by a decrease in the fraction of absorbed light energy spent on the photochemical work and an increase in the proportion of non-photosynthetic thermal quenching. These changes indicate the photosynthetic down-regulation that acts as a universal photoprotective mechanism. During the midday hours, the combination of high air temperature and low air humidity leads to the decrease in the maximum photochemical quantum yield of photosystem II(Fv/Fm) and the efficiency of photosynthesis(PABS). The parameters of leaf gas exchange show the significant differences in these values between the control and experimental variants. During the morning hours, the Siberian crabapple, growing in the Irkutsk City,assimilates carbon dioxide more intensively. Due to the higher air humidity, the stomata are kept open and the necessary amount of carbon dioxide entries the sites of carboxylation. The low air humidity combined with wind in the experimental variants leads to the unreasonably high water loss in the crabapple leaves by more than 27% as compared to the control variant(Irkutsk City). However, water use efficiency in the morning hours increases during plant photosynthetic processes, i.e., 42% higher than that of control. This,apparently, is a reflection of the adaptation processes of the Siberian crabapple to the air drought and parching wind.

关键词： air drought chlorophyll fluorescence leaf gas exchange pigments water use efficiency

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Radiation of a TM mode from an open end of a three-layer dielectric capillary

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Chinese Physics B 2024年第7期33卷 311-318页

作者： Sergey NGalyamin alexandr MAltmark St.Petersburg State University 7/9Universitetskayanab.St.Petersburg 199034Russia St.Petersburg Electrotechnical University“LETI” 5ProfessoraPopovaSt.Petersburg 197022Russia

Modern trends in beam-driven radiation sources include the interaction of Cherenkov wakefields in open-ended circular waveguides with complicated dielectric linings, with a three-layer dielectric capillary recently proposed to reduce radiation divergence being a representative example [Opt. Lett. 45 5416(2020)]. We present a rigorous approach that allows for an analytical description of the electromagnetic processes that occur when the structure is excited by a single waveguide TM mode. In other words, the corresponding canonical waveguide diffraction problem is solved in a rigorous formulation. This is a continuation of our previous papers which considered simpler cases with a homogeneous or two-layer dielectric filling. Here we use the same analytical approach based on the Wiener–Hopf–Fock technique and deal with the more complicated case of a three-layer dielectric lining. Using the obtained rigorous solution, we discuss the possibility of manipulating the far-field radiation pattern using a third layer made of a low permittivity material.

关键词： diffraction radiation open-ended waveguide Wiener–Hopf technique Cherenkov radiation

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Quantum algorithms for matrix operations and linear systems of equations

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Communications in Theoretical Physics 2024年第3期76卷 100-112页

作者： Wentao Qi alexandr I Zenchuk Asutosh Kumar Junde Wu School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS ChernogolovkaRussia P.G.Department of Physics Gaya CollegeMagadh UniversityRampurGaya 823001India Harish-Chandra Research Institute HBNIChhatnag RoadJhunsiPrayagraj 211019India Vaidic and Modern Physics Research Centre Bhagal BhimBhinmalJalore 343029India

Fundamental matrix operations and solving linear systems of equations are ubiquitous in scientific *** the‘sender-receiver’model,we propose quantum algorithms for matrix operations such as matrix-vector product,matrix-matrix product,the sum of two matrices,and the calculation of determinant and inverse *** encode the matrix entries into the probability amplitudes of the pure initial states of *** applying proper unitary transformation to the complete quantum system,the desired result can be found in certain blocks of the receiver’s density *** quantum protocols can be used as subroutines in other quantum ***,we present an alternative quantum algorithm for solving linear systems of equations.

关键词： matrix operation systems of linear equations ‘sender-receiver’quantum computation model quantum algorithm

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A system-integrated approach for the design of tourist areas at the local level under changing conditions:A case study in the Altay Mountains

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Regional Sustainability 2024年第2期5卷 89-102页

作者： alexandr Nikolaevich DUNETS Evgeniya Mikhailovna TABAKAEVA HAN Fang Department of Scientific and Innovative Development Altai State UniversityBarnaul656049Russia Department of Recreational Geography ServiceTourism and HospitalityInstitute of GeographyAltai State UniversityBarnaul656049Russia State Key Laboratory of Desert and Oasis Ecology Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsXinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi830011China

The existing approaches for the design of tourist areas often lead to limited flexibility in project *** realize a more flexible approach,in this study,we formulated a model for planning and designing tourist areas at the local ***,specific tools for analyzing tourist areas and ensuring sustainable development under changing conditions were *** study was conducted in two tourist regions,Biryuzovaya Katun tourist complex and Belokurikha destination(including Belokurikha City with Belokurikha 2 Gornaya tourist complex and surrounding areas),in the Altay *** employed the recreation opportunity spectrum and proposed a system-integrated programming approach for the design of tourist areas at the destination and site *** key of this approach was the collection and analysis of current spatial data,including the spatial distribution of attractions and visitor *** constructed heat maps using video recording and unmanned aerial vehicle(UAV)observation ***,we analyzed the video stream using an image-analyzing framework You Only Look Once(YOLO)v5 *** heat map of visitor flows based on video recording data in the Andreevskaya Sloboda museum of Belokurikha 2 Gornaya tourist complex allowed us to highlight the most attractive sites in this area and classify them into one of three types:points of functional concentration,points of transitional concentration,and points of *** heat maps in Biryuzovaya Katun tourist complex,created using UAV observation data,allowed us to determine the spatiotemporal patterns of visitor flows and tourists’preferences throughout the day within four time intervals:09:00-12:00,13:00-14:00,14:00-15:00,and 16:00-18:00(LST).The maximum visitor flow density occurred from 16:00 to 18:00 in the beach area of the artificial lake.A comparison between the visitor-concentrated sites and the current facilities provided insights into the demand for attractions and facilities and

关键词： Tourism planning Tourist areas Unmanned aerial vehicle(UAV) Visitor flows Heat map Altay Mountains

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Factors that influence the results of indirect decompression employing oblique lumbar interbody fusion

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World Journal of Orthopedics 2024年第8期15卷 734-743页

作者： Andrey E Bokov Svetlana Y Kalinina Mingiyan I Khaltyrov alexandr P Saifullin Anatoliy A Bulkin Department of Neurosurgery Institute of Traumatology and OrthopedicsPrivolzhsky Research Medical UniversityNizhny Novgorod603005Russia Department of Traumatology Orthopedics and NeurosurgeryPrivolzhsky Research Medical UniversityNizhny Novgorod603005Russia

BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal *** the other hand,the reported rate of revision surgery after indirect decompression highlights the necessity of working out prediction models for the radiographic results of indirect decompression with assessing their clinical *** To assess factors that influence radiographic and clinical results of the indirect decompression in patients with stenosis of the lumbar *** This study is a single-center cross-sectional evaluation of 80 consecutive patients(17 males and 63 females)with lumbar spinal stenosis combined with the instability of the lumbar spinal *** underwent single level or bisegmental spinal instrumentation employing oblique lumbar interbody fusion(OLIF)with percutaneous pedicle screw *** results of the indirect decompression were assessed using computerized tomography,while MacNab scale was used to assess clinical *** After indirect decompression employing anterior reconstruction using OLIF,the statistically significant increase in the disc space height,vertebral canal square,right and left lateral canal depth were detected(Р<0.0001).The median(M)relative vertebral canal square increase came toМ=24.5%with 25%-75%quartile border(16.3%;33.3%)if indirect decompression was achieved by restoration of the segment *** patients with the reduction of the upper vertebrae slip,the median of the relative increase in vertebral canal square accounted for 49.5%with 25%-75%quartile border(2.35;99.75).Six out of 80 patients(7.5%)presented with unsatisfactory results because of residual nerve root *** critical values for lateral recess depth and vertebral canal square that were associated with indirect decompression failure were 3 mm and 80 mm2 *** Indirect decompression employing anterior reconstruction is achieved by the increase in disc height al

关键词： Indirect decompression Anterior reconstruction Central lumbar spinal stenosis Degenerative spondylolisthesis Lateral recess stenosis Spinal instability Oblique lateral interbody fusion

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Cu/TiO_(2) Photocatalysts for CO_(2) Reduction: Structure and Evolution of the Cocatalyst Active Form

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Transactions of Tianjin University 2024年第2期30卷 140-151页

作者： Andrey A.Saraev Anna Yu.Kurenkova Denis D.Mishchenko alexandr L.Trigub Evgeniy Yu.Gerasimov Ekaterina A.Kozlova Boreskov Institute of Catalysis Lavrentieva Ave 5Novosibirsk 630090Russia Synchrotron Radiation Facility SKIF Boreskov Institute of CatalysisNikol’skiy Ave 1Kol’tsovo 630559Russia National Research Center “Kurchatov Institute”Kurchatova Sq 1Moscow 123182Russia

Extensive work on a Cu-modified TiO_(2) photocatalyst for CO_(2) reduction under visible light irradiation was conducted. The structure of the copper cocatalyst was established using UV-vis diff use refl ectance spectroscopy, high-resolution transmis- sion electron microscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. It was found that copper exists in different states (Cu 0 , Cu^(+) , and Cu^(2+) ), the content of which depends on the TiO_(2) calcination temperature and copper loading. The optimum composition of the cocatalyst has a photocatalyst based on TiO_(2) calcined at 700℃ and modified with 5 wt% copper, the activity of which is 22 μmol/(h·g cat ) (409 nm). Analysis of the photocatalysts after the photocatalytic reaction disclosed that the copper metal on the surface of the calcined TiO_(2) was gradually converted into Cu_(2) O during the photocatalytic reaction. Meanwhile, the metallic copper on the surface of the noncalcined TiO_(2) did not undergo any trans- formation during the reaction.

关键词： Photocatalysis Photocatalytic CO_(2)conversion Visible light Titanium dioxide Copper Copper oxides Methane formation Photocatalyst transformation

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Prediction of coating uniformity in batch fluidized-bed coating process

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Particuology 2022年第2期20卷 41-46页

作者： Andrey A.Lipin alexandr G.Lipin Department of Processes and Apparatuses of Chemical Technology Ivanovo State University of Chemistry and TechnologyIvanovoRussia

Coating of particulate materials in fluidized beds is a widely used technique to eliminate particle agglomeration,provide slow release of an active substance,or protect active *** thin polymer shells are applied on a particle surface,it is important to determine the process parameters that provide coating *** this study,the degree of coverage,defined as the fraction of the coated surface of the particles,is proposed as a quantitative criterion of coating uniformity.A new model for the batch fluidized-bed coating process is *** model allows prediction of the function of particle distribution according to the degree of coverage at a given process time and thereby enables assessment of coating *** algorithm for the numerical solution of model equations for a batch fluidized-bed coater is *** influences of the main process parameters on the coating uniformity were shown.

关键词： Coating uniformity Degree of coverage Encapsulation Fluidized-bed coating Mathematical modeling

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Peculiarities of the electrocaloric effect in relaxors

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Journal of Materiomics 2023年第1期9卷 223-228页

作者： Elena Smirnova Galina Sotnikova Andrei Sotnikov alexandr Kapralov Gennadiy Gavrilov Ioffe Institute 26 PolitekhnicheskayaSt Petersburg194021Russian Federation

A comprehensive study and detailed analysis of pyroelectric and electrocaloric effects in relaxor ferroelectrics based on lead magnesium niobate as a promising object for such investigations have been carried *** was found that even at the maximum values of pyroelectric coefficients the electrocaloric response inextricably linked with the pyroelectric effect does not exceed 1°C in the temperature range from 10 to 60°C under DC electric field up to 60 kV/*** conditions are the most demanded for the operation of electrocaloric cooling *** for the future as to increasing the efficiency of the main elements for such devices is discussed.

关键词： Relaxors Electrocaloric effect Pyroelectric effect

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Elucidation of the sodiation/desodiation mechanism in Ca_(0.5)Ti_(2)(PO_(4))_(3)/C as promising electrode for sodium batteries: New insights into the phase transitions

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Journal of Energy Chemistry 2022年第7期31卷 36-44,I0002页

作者： Abdelhaq Nassiri Noha Sabi Angelina Sarapulova Yingjin Wei Bouchaib Manoun Sylvio Indris alexandr Missyul Helmut Ehrenberg Ismael Saadoune IMED-Lab Faculty of Science and Technology-Cadi Ayyad University(UCA)Av.A.El KhattabiP.B.549MarrakeshMorocco Institute for Applied Materials(IAM) Karlsruhe Institute of Technology(KIT)P.O.Box 364076021 KarlsruheGermany Key Laboratory of Physics and Technology for Advanced Batteries(Ministry of Education) Jilin Engineering Laboratory of New Energy Materials and TechnologyCollege of PhysicsJilin UniversityChangchun 130012JilinChina MSN Mohamed VI Polytechnic UniversityLot 660Hay Moulay RachidBen Guerir 43150Morocco CELLS-ALBA Synchrotron E-08290 Cerdanyola del VallesBarcelonaSpain Technology Development Cell(Techcell) Technology Transfer Office(TTO)Mohamed VI Polytechnic UniversityLot 660Hay Moulay RachidBen Guerir 43150Morocco

The structure evolution and electrochemical performance of Na SICON-type Ca_(0.5)Ti_(2)(PO_(4))_(3) for sodium batteries are *** phosphate was synthesized by a solid-state method,and the obtained particles were coated with carbon using *** compound crystallizes in the rhombohedral system with space group *** presence of carbon in the Ca_(0.5)Ti_(2)(PO_(4))_(3)/C composite was confirmed by Raman and Thermogravimetric *** electrochemical performance of Ca_(0.5)Ti_(2)(PO_(4))_(3)/C was investigated in the potential window 1.5–3.0 V *** metal at different scan *** compound is able to initially intercalate/deintercalate 1.6/1.15 Na per formula unit,*** operando synchrotron diffraction was done in the potential window 0.02–3.0 V ***|Na+and revealed the occurrence of several reaction regions upon first *** to 4 Na+ion per formula unit can be inserted during the first *** intensive refinement of the synchrotron X-ray diffraction(SXRD)patterns of discharged Ca_(0.5)Ti_(2)(PO_(4))_(3) evidenced the existence of five regions depending on the sodium content while the crystal structures of new phases were elucidated for the first time where sodium insertion occurs in the unusual M3 and M’3 sites of the Na SICON structure.

关键词： Sodium-ion batteries Phosphates Synchrotron Mechanism Energy storage

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Physical Processes in Barrier Discharge Lamp Working in He/D2O Mixture

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高电压技术 2013年第9期39卷 2193-2200页

作者： Dmitry Levko alexandr Shuaibov alexandr Minya Roksolana Gritzak Zoltan Gomoki Laboratoire Plasma et Conversion d'Energie (LAPLACE) Universite de Toulouse UPS INPT Toulouse 118 route de Narbonne F-31062 Toulouse cedex 9 France Uzhgorod National University Pidhima vul. 46 88000 Uzhgorod Ukraine

This paper presents both results of a numerical modeling and an experimental study of the influence of various parameters on the radiation characteristics of barrier discharge lamp working in He/D2O *** is obtained that the intensity of ultraviolet radiation is a non-monotonic function of both the water and the helium *** experimental results also show that the increase of both the discharge voltage and the discharge pulse frequency leads to the increase of radiation *** comparison between the experimentally obtained data and the results of numerical modeling allows us to define the mechanism controlling the ultraviolet radiation in He/D2O mixture at various parameters.

关键词：放电灯混合物物理过程紫外线辐射势垒数值模拟辐射强度非单调函数

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