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Epitaxial thin-film Pd_(1-x)Fe_(x) alloy: a tunable ferromagnet for superconducting spintronics

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Science China Materials 2021年第5期64卷 1246-1255页

作者： Alireza Esmaeili Igor V.Yanilkin Amir I.Gumarov Iskander R.Vakhitov Bulat F.Gabbasov Roman V.Yusupov Dmitriy A.Tatarsky Lenar R.Tagirov Institute of Physics Kazan Federal UniversityKazan 420008Russia Institute for Physics of Microstructures of RAS Nizhny Novgorod 603950Russia Zavoisky Physical-Technical Institute FRC Kazan Scientific Center of RASKazan 420029Russia

Thin epitaxial films of the palladium-rich Pd_(1-x)Fe_(x) alloy were synthesized and extensively studied as a tunable ferromagnetic material for superconducting spintronics. The(001)-oriented Mg O single-crystal substrate and the composition range of x = 0.01–0.07 were chosen to support the epitaxial growth and provide the films with magnetic properties spanning from very soft ferromagnet for memory applications to intermediately soft and moderately hard for the programmable logic and circuit biasing, respectively. Dependences of the saturation magnetization, Curie temperature and three magnetic anisotropy constants on the iron content x were obtained for the first time from the analyses of the magnetometry and ferromagnetic resonance data. The experimental results were discussed based on existing theories of dilute ferromagnetic alloys. Simulation of the hysteresis loops within the Stoner-Wohlfarth model indicates the predominant coherent magnetic moment rotation at cryogenic temperatures. The obtained results were compiled in a database of magnetic properties of a palladium-iron alloy in a single-crystal thin-film form considered as a material for superconducting spintronics.

关键词： alloy ferromagnetic palladium

Struggle zone: alpine shrubs are limited in the Southern Urals by an advancing treeline and insufficient snow depth

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Journal of Forestry Research 2024年第6期35卷 1-12页

作者： Andrey A.Grigoriev Vladimir S.Mikryukov Yulia V.Shalaumova Pavel A.Moiseev Sergey O.Vuykhin Jesús J.Camarero Institute of Plant and Animal Ecology Ural BranchRussian Academy of SciencesSt.8 Marta 202EkaterinburgRussia 6201442 Institute of Ecology and Earth Sciences University of TartuSt.Liivi 250409 TartuEstonia Pyrenean Ecology Institute St.Montañana 100550059 SaragossaSpain

In recent decades,the rapid climate warming in polar and alpine regions has been accompanied by an expan-sion of shrub ***,little is known about how changes in shrub distribution will change as the distribution of tree species and snow cover changes as temperatures *** this work,we analyzed the main environmental factors influencing the distribution and structure of Juniperus sibir-ica,the most common shrub species in the Southern Ural *** mapping and digital elevation models,we demonstrated that *** forms a well-defined vegeta-tion belt mainly between 1100 and 1400 m *** this zone,the abundance and cover of *** are influenced by factors such as rockiness,slope steepness,water regime and tree(Picea obovata)*** analysis of data spanning the past 9 years revealed an upward shift in the distribution of *** with a decrease in its *** primary limit-ing factors for the distribution of *** were the removal of snow cover by strong winter winds and competition with *** a consequence of climatic changes,the tree line and forest limit have shifted upward,further restricting the distribution of *** to higher elevations where com-petition for light with trees is reduced and snow cover is sufficiently deep.

关键词： Juniperaceae Juniperus sibirica Snowpack cover Shrubline Shrub-tree competition Southern Urals Tree line

Influence of the safety factor profile on the particle and heat transport in the Globus-M spherical tokamak

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Plasma Science and Technology 2019年第11期21卷 1-6页

作者： A YU TELNOVA G S KURSKIEV E O KISELEV N N BAKHAREV V K GUSEV N A KHROMOV S YU MEDVEDEV V B MIINAEV I V MIROSHNIKOV M I PATROV Yu V PETROV N V SAKHAROV A D SLADKOMEDOVA P B SHCHEGOLEV V V SOLOKHA V A TOKAREV S YU TOLSTYAKOV E A TUKHMENEVA Ioffe Institute Saint-Petersburg 194021Russia Keldysh Institute Russian Academy of SciencesMoscow 125047Russia NRC'Kurchatov Institute’ Moscow 123098Russia

The advanced tokamak scenario is a promising operation scenario for ITER and fusion neutron *** this scenario the minimum value of the safety factor in the center of the plasma exceeds *** the compact spherical tokamak Globus-M,the formation of such conditions is possible with neutral beam injection at the current ramp-up *** to the slower diffusion of current inside the plasma,a zone is formed with reduced heat and particle transport across the magnetic field,which affects the temperature and density profiles of the *** leads to the peaked density profile formation and improvement of the energy confinement *** achieve a high fraction of the bootstrap current,it is necessary to increase the plasma *** the same time,the maximum allowable pressure is limited to the normalized beta limit.

关键词： advanced tokamak mode transport analysis internal transport barriers

CO_(2)-Free Calcium Carbide Manufacturing: Demanded Strategy in the Carbon-Neutral Chemical Industry

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Chinese Journal of Chemistry 2023年第24期41卷 3611-3617页

作者： Dmitriy E.Samoylenko Konstantin S.Rodygin Valentine P.Ananikov Institute of Chemistry Saint Petersburg State University7/9 Universitetskaya nabSt.Petersburg199034 Russia Zelinsky Institute of Organic Chemistry Russian Academy of SciencesLeninsky pr.47Moscow119991 Russia

Calcium carbide is considered a possible key component in the sustainable carbon cycle,including convenient recycling of carbon wastes to industrial ***,currently employed CaC2 manufacturing process produces significant amounts of CO_(2).One of the main factors of its appearance is the formation of carbon oxide during the *** reaction of lime ore with coal inevitably results in the formation of CO and the loss of one carbon *** is usually burnt,forming CO_(2) to maintain the required high temperature during synthesis – 2200 ℃.In the present study,we discuss that the use of calcium metal instead of lime represents a good opportunity to prevent CO_(2) emission since the reaction of Ca with carbon occurs in an atom-efficient manner and results in only CaC_(2) at a much lower temperature of 1100 ℃.Here,the reaction of Ca with carbon was successfully tested to synthesize CaC_(2).The desired product was isolated in gram-scale amounts in 97.2% yield and 99% *** environmental friendliness of the proposed method originates from the calculations of the *** is provided concerning the cost factor of Ca within the considered process.

关键词： CO_(2)emission CaC_(2) Carbon cycle Sustainable chemistry Green chemistry

Evolution of metabolic scaling among the tetrapod:effect of phylogeny,the geologic time of class formation,and uniformity of species within a class

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Integrative Zoology 2022年第5期17卷 904-917页

作者： Valery M.GAVRILOV Tatiana B.GOLUBEVA Andrey V.BUSHUEV Department of Vertebrate Zoology M.V.Lomonosov Moscow State UniversityMoscowRussia Zvenigorod Biological Station M.V.Lomonosov Moscow State UniversityMoscowRussia

The metabolic scaling in the animal has been discussed for over 90 years,but no consensus has been *** analysis of 2126 species of vertebrates reveals a signiﬁcant allometric exponent *** show that classes of terrestrial vertebrates exhibit the evolution of metabolic *** the allometric coefﬁcient“a”and the allometric exponent“b”change naturally,but differently depending on the geological time of group *** allometric coefﬁcient“a”shows the measure of the evolutionary development of systems that forms resting metabolism in *** classes,such as birds and mammals,have a metabolic rate that is in an order of magnitude higher than that in ectothermic classes,including amphibians and *** the terrestrial vertebrate phylogeny,weﬁnd that the metabolic scaling is characterized by 3 main allometric exponent values:b=3/4(mammals),b>3/4(ectotherms,such as amphibians and reptiles),and b<3/4(birds).The hetero-geneity of the allometric exponent is a natural phenomenon associated with the general evolution of *** scaling factor decreases depending on both the external design and the size(birds vs mammals)of the *** metabolic rate and uniformity of species within a class increase as the geological start date of for-mation of the class approaches the present *** higher the mass-speciﬁc standard metabolic rate in the class,the slower metabolic rate grows with increasing body size in this *** results lay the groundwork for further exploration of the evolutionary and ecological aspects of the development of metabolic scaling in animals.

关键词： geological time metabolic rate scaling

Stabilization versus decomposition in alpine ecosystems of the Northwestern Caucasus:The results of a tea bag burial experiment

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Journal of Mountain Science 2018年第8期15卷 1633-1641页

作者： Tatiana G.ELUMEEVA Vladimir G.ONIPCHENKO Asem A.AKHMETZHANOVA Mikhail I.MAKAROV Joost A.KEUSKAMP Department of Geobotany Biological FacultyLomonosov Moscow State University119234 Leninskie Gory 1/12MoscowRussia Department of General Soil Science Faculty of Soil ScienceLomonosov Moscow State University119234 Leninskqe Gory 1/12MoscowRussia Ecology 8:Biodiversity Group Utrecht UniversityP.O.Box 80.0563508 TB UtrechtThe Netherlands Netherlands Institute of Ecology(NIOO-KNA W) P.O.Box 596700 AB WageningenThe Netherlands

Mountainous areas exhibit highly variable decomposition rates as a result of strong local differences in climate and vegetation type. This paper describes the effect of these factors on two major determinants of the local carbon cycle: litter decomposition and carbon stabilization. In order to adequately reflect local heterogeneity, we have sampled 12 typical plant communities of the Russian Caucasus. In order to minimize confounding effects and encourage comparative studies, we have adapted the widely used tea bag index(TBI) that is typically used in areas with low decomposition. By incubating standardized tea litter for a year, we investigated whether(1) initial litter decomposition rate(k) is negatively correlated with litter stabilization(S) and(2) whether k or S exhibit correlations with altitude and other environmental conditions. Our results show that S and k are not correlated. Altitude, p H, and water content significantly influenced the stabilization factor S, while soil-freezing had no influence. In contrast, none of these factors predicted the decomposition rate k. Based on our data, we argue that collection of decomposition rates alone, as is now common practice, is not sufficient to understand carbon input to soils and can potentially lead to misleading results. Our data on community-specific decomposition and stabilization rates further constrain estimates of litter accumulation in subalpine communities and the potential effects of climate change.

关键词： Litter decomposition Alpine communities Tea bag index Carbon cycle

Latitudinal and temporal shifts in the radial growth-climate response of Siberian larch in the Polar Urals

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Journal of Mountain Science 2018年第4期15卷 722-729页

作者： Vladimir V.KUKARSKIH Nadezhda M.DEVI Pavel A.MOISEEV Andrey A.GRIGORIEV Maksim O.BUBNOV Institute of plant and animal ecology UB RAS 8-Marta 202/3 620144 Ekaterinburg Russia

This paper presents a dendroclimatic analysis of Siberian larch trees sampled along a latitudinal 260-km transect located in the Polar Urals,Russia. Three standardised chronologies were built over a length of 230–293 years using 79 individual tree-ring chronologies collected in the southern,middle and northern parts of the Polar *** correlation functions showed that the annual growth of the larches was mainly influenced by the air temperatures in June and July. The relative role of the temperatures increased from south to north. Daily air temperature data analysis revealed that the duration of the growing season in the northern part of the Polar Urals is 24 days less than that in the southern part. At the present time, air temperatures exceeded threshold of 8~℃, 5 days earlier than it did in the beginning of the 20 th century In response to the increase in the duration of the growing season and the changing winter conditions in the Polar Urals over the last 130 years, radial growth–temperature relationships in larches have weakened;this effect was strongly pronounced in the southern part of the Polar Urals.

关键词： Tree rings Dendroclimatilogy Larix sibirica Growing season Polar Urals

Inverse Problems in Graph Theory: Nets

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Communications in Mathematics and Statistics 2019年第1期7卷 69-83页

作者： A.A.Makhnev M.P.Golubyatnikov Wenbin Guo Institute of Mathematics and Mechanics Ural Branch of the Russian Academy of SciencesYekaterinburgRussia Ural Federal University named after the First President of Russia B.N.Yeltsin YekaterinburgRussia University of Science and Technology of China HefeiChina

Let Г be a distance-regular graph of diameter 3 with strong regular graph Г_(3).The determination of the parameters Г_(3) over the intersection array of the graph Г is a direct *** an intersection array of the graph Г with respect to the parameters Г_(3) is an inverse ***,inverse problemswere solved for Г_(3) by Makhnev and *** this paper,we study the intersection arrays of distance-regular graph Г of diameter 3,for which the graph Г_(3) is a pseudo-geometric graph of the net PGm(n,m).New infinite series of admissible intersection arrays for these graphs are *** also investigate the automorphisms of distance-regular graph with the intersection array{20,16,5;1,1,16}.

关键词： Distance-regular graph Pseudo-geometric graph Strong regular graph

Experimental Study of Liquid Metal Flow for the Development of a Contact-Less Control Technique

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1553-1564页

作者： Aleksandr Poluyanov Ilya Kolesnichenko Laboratory of Technological Hydrodynamics Institute of Continuous Media Mechanics of the Ural Branch of Russian Academy of Science(ICMM UB RAS)Perm614018Russia

The article presents an experimental study on the flow of an eutectic gallium alloy in a cylindrical cell,which is placed in an alternating magnetic *** magnetic field is generated by a coil connected to an alternating current *** coil is located at a fixed height in such a way that its plane is perpendicular to the gravity vector,which in turn is parallel to the axis of the *** position of the cylinder can vary in height with respect to the *** forced flow of the considered electrically conductive liquid is generated due to the action of the localized electromagnetic *** is assumed that under the action of the alternating magnetic field,the liquid is heated uniformly,and the resulting heat is quickly absorbed by the forced flow,so that liquid free convection can be *** experiment is carried out using an ultrasonic Doppler *** transducer is installed in the axially located cylinder sluice and the other transducer is placed in the near-wall *** to the results,a velocity profile,corresponding to a two-tori flow pattern can be hardly obtained in the low frequency range of the power ***,this is possible in the high frequency *** average velocity profiles depend essentially on the location of the coil relative to the *** spectral analysis of velocity signals shows that the amplitude of the velocity pulsations is comparable to the average value of the flow *** experimental results and their verification through comparison with numerical calculations are intended to support the development of new methods for reducing the intensity of vortex flows during the electromagnetic separation of impurities through an electromagnetic induction mechanism(able to produce an electromotive force that displaces particles).

关键词： Ultrasonic doppler velocimeter electrically conductive medium azimuthal pinch experiment in liquid metal magnetohydrodynamics