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Integrative Zoology 2022年第5期17卷 849-878页

作者： alexander n.kuznetsov Borissiak Paleontological Institute Russian Academy of SciencesMoscowRussia

Comparative study of terrestrial locomotion of 4ﬁsh genera including Anabas,Channa,Clarias,and Monopterus,was performed in experimental setting with the substrate surface of wet *** special adaptations for terrestrial locomotion were ***ﬁsh uses for propulsion on land what it already ***-shaped Monopterus crawls by body undulations in a serpentine or sidewinding technique,the latter of which was not previously observed beyond *** other 3ﬁsh genera walk by body oscillations using stiff appendages as *** they are located anteriorly,as the serrate operculum in Anabas and the preaxial spine of the pectoralﬁn in Clarias,the propulsion is termed prolocomotor,when posteriorly,as the spiny analﬁn in Channa—*** is the heaviestﬁsh walking out of water in our days,quite comparable in size withﬁrst Devonian tetrapods Acan-thostega and Tulerpeton.A theoretical calculation is suggested for the upper size limit of aﬁsh capable of terrestrial walking without special locomotor *** should be roughly 20 cm in the vertical dimension of the trunk,which is just a little above the known size of Devonian tetrapodomorphﬁshes Panderichthys and *** metalocomotor walking technique of Channa is suggested as the closest extant model for terrestrial locomotion at theﬁsh-tetrapod *** major difference is that the metalocomotor propulsor in Channa is represented by the analﬁn,while in tetrapodomorphs by the pelvicﬁ*** sprawled pelvicﬁns were advantageous in respect of reduced requirement for side-to-side tail swinging.

关键词： ﬁsh-tetrapod transition metalocomotor propulsion prolocomotor propulsion snakehead

A blind climber:The first evidence of ultrasonic echolocation in arboreal mammals

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Integrative Zoology 2017年第2期12卷 172-184页

作者： Aleksandra A.PAnYUTInA alexander n.kuznetsov Ilya A.VOLODIn Alexei V.ABRAMOV Irina B.SOLDATOVA Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Department of Vertebrate Zoology Faculty of BiologyLomonosov Moscow State UniversityMoscowRussia Scientific Research Department Moscow ZooMoscowRussia Zoological Institute Russian Academy of SciencesSaint PetersburgRussia Joint Vietnam-Russian Tropical Research and Technological Centre HanoiVietnam

The means of orientation is studied in the Vietnamese pygmy dormouse Typhlomys chapensis,a poorly known enigmatic semi-fossorial semi-arboreal *** on eye structure are presented,which prove that Typhlomys(translated as“the blind mouse”)is incapable of object vision:the retina is folded and retains no more than 2500 ganglion cells in the focal plane,and the optic nerve is subject to ***,Typhlomys has no other means for rapid long-range orientation among tree branches other than *** vocalization recordings at the frequency range of 50-100 kHz support this *** vocalizations are represented by bouts of up to 7 more or less evenly-spaced and uniform frequency-modulated sweep-like pulses in rapid ***,these sweeps are similar to frequency-modulated ultrasonic echolocation calls of some bat species,but they are too faint to be revealed with a common bat *** recording video simultaneously with the ultrasonic audio,a significantly greater pulse rate during locomotion compared to that of resting animals has been *** findings of locomotion-associated ultrasonic vocalization in a fast-climbing but weakly-sighted small mammal ecotype add support to the“echolocation-first theory”of pre-flight origin of echolocation in bats.

关键词： arboreal locomotion reduced eyes Rodentia Typhlomys ultrasonic echolocation

Interstitial Doping of SnO_(2) Film with Li for Indium-Free Transparent Conductor

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Chinese Physics Letters 2024年第3期41卷 140-145页

作者：陈兴谦李昊臻陈伟梅增霞 alexander Azarov Andrej kuznetsov 杜小龙 Beijing national Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China Department of Physics Centre for Materials Science and NanotechnologyUniversity of OsloP.O.Box 1048BlindernN-0316 OsloNorway Guangdong SinoPrime Technology Co. Ltd.Dongguan 523808China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

SnO_(2)films exhibit significant potential as cost-effective and high electron mobility substitutes for In_(2)O_(3)*** this study,Li is incorporated into the interstitial site of the SnO_(2)lattice resulting in an exceptionally low resistivity of 2.028×10^(-3)Ω·cm along with a high carrier concentration of 1.398×10^(20)cm^(-3)and carrier mobility of 22.02 cm^(2)/V·s.

关键词： exceptional resistivity substitute

GaZn-VZn acceptor complex defect in Ga-doped ZnO

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Science China(Physics,Mechanics & Astronomy) 2018年第7期61卷 67-72页

作者： AiHua Tang ZengXia Mei Yaonan Hou LiShu Liu Vishnukanthan Venkatachalapathy alexander Azarov Andrej kuznetsov XiaoLong Du Key Laboratory for Renewable Energy Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Department of Physics Centre for Materials Science and Nanotechnology University ofOslo Oslo N-0316 Norway School of Physieal Sciences University of Chinese Academy of Sciences Beijing 100049 China

Gallium （Ga）-doped ZnO is regarded as a promising plasmonic material with a wide range of applications in plasmonics. In this study, zinc self-diffusion experiments are adopted to disclose the nature of the dominant compensating defect in Ga-doped ZnO isotopic heterostructures. The （GaZn-VZ.）- complex defect, instead of the isolated VZn^2-, is identified as the predominant compensating acceptor center responsible for the low donor doping efficiency. The comparative diffusion experiments operated by the secondary ion mass spectrometry reveal a -0.78 eV binding energy of this complex defect, which well matches the electrical activation energy derived from the temperature-dependent Hall effect measurements （-（0.82±0.02） eV）. These findings contribute to an essential understanding of the （GaZn-VZn）- complex defect and the potential engineering routes of heavily Ga-doped ZnO.

关键词： Ga-doped ZnO complex defect self-diffusion

A novel strategy of smart manipulation by micro-scale oscillatory networks of the reactionary zones for enhanced extreme thrust control of the next-generation solid propulsion systems

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Defence Technology（防务技术） 2018年第5期14卷 635-642页

作者： alexander n.Lukin Bldg.9 Tupik ZvezdniyTuapseKrasnodar TerritoryRU 352808Russian Federation

The main aim of this research is to get a better knowledge and understanding of the micro-scale oscillatory networks behavior in the solid propellants reactionary zones. Fundamental understanding of the micro-and nano-scale combustion mechanisms is essential to the development and further improvement of the next-generation technologies for extreme control of the solid propellant thrust. Both experiments and theory confirm that the micro-and nano-scale oscillatory networks excitation in the solid propellants reactionary zones is a rather universal phenomenon. In accordance with our concept,the micro-and nano-scale structures form both the fractal and self-organized wave patterns in the solid propellants reactionary zones. Control by the shape, the sizes and spacial orientation of the wave patterns allows manipulate by the energy exchange and release in the reactionary zones. A novel strategy for enhanced extreme thrust control in solid propulsion systems are based on manipulation by selforganization of the micro-and nano-scale oscillatory networks and self-organized patterns formation in the reactionary zones with use of the system of acoustic waves and electro-magnetic fields, generated by special kind of ring-shaped electric discharges along with resonance laser radiation. Application of special kind of the ring-shaped electric discharges demands the minimum expenses of energy and opens prospects for almost inertia-free control by combustion processes. nano-sized additives will enhance self-organizing and self-synchronization of the micro-and nano-scale oscillatory networks on the nanometer scale. Suggested novel strategy opens the door for completely new ways for enhanced extreme thrust control of the solid propulsion systems.

关键词： Solid propulsion systems Extreme thrust control Reactionary zones Micro-scale oscillatory networks Self-organized wave patterns Energy-releasing areas

new characterizations of finite supersoluble groups

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Science China Mathematics 2008年第5期51卷 827-841页

作者： alexander n SKIBA Department of Mathematics Gomel State University of F.Skorina

Let A be a subgroup of a group G and X a nonempty subset of G. A is called an X-semipermutable subgroup of G if A has a supplement T in G such that for every subgroup T 1 of T there exists an element x ∈ X such that ... 详细信息

关键词： finite groups supplement 2-maximal subgroups X-semipermutable supersoluble groups 20D10

numerical investigation into the influence of the punch shape on the mechanical behavior of pharmaceutical powders during compaction

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Particuology 2014年第5期12卷 116-131页

作者： alexander Krok Marin Peciar Roman Fekete Slovak University of Technology in Bratislava Faculty of Mechanical EngineeringBratislavaSlovak Republic

During the production of pharmaceutical tablets using powder compaction, certain common problems can occur, such as sticking, tearing, cutting, and lamination. In the past, the compressibility of the powder was calculated only along the axis of the device; consequently, critical areas of the material throughout the volume could not be identified. Therefore, finite element method （FEM） can be used to predict these defects in conjunction with the use of an appropriate constitutive model. This article summarizes the current research in the field of powder compaction, describes the Drucker-Prager Cap model calibration procedure and its implementation in FEM, and also examines the mechanical behavior of powder during compaction. In addition, the mechanical behavior of pharmaceutical powders in relation to changes in friction at the wall of the system is examined, and the dependence of lubrication effect on the geometry of the compaction space is also investigated. The influence of friction on the compaction process for the flat-face, fiat-face radius edge, and standard convex tablets is examined while highlighting how the effects of friction change depending on the shape of these tablets.

关键词： Powder Die compaction FEM

Tribological properties of the beetle leg joints

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Friction 2024年第12期12卷 2791-2807页

作者： Konstantin nADEIn alexander KOVALEV Stanislav n.GORB Functional Morphology and Biomechanics Zoological InstituteChristian-Albrechts University of KielAm Botanischen Garten 1-924118 KielGermany

Tribological properties of femoro-tibial leg joints in two beetles,darkling beetle Zophobas morio and Congo rose chafer Pachnoda marginata were *** low friction of 0.004 was revealed by the direct measurements in the *** is assumed that semi-solid lubricant functioning as in technical bearings is one of the leading factors of the friction *** of the surface texture and physical chemical properties(hydrophobicity)on the cuticle friction was *** of the surface texture to the tribological properties of contacting surfaces was examined by the measurement in the tribosystem“contacting surface/glass”.It is supposed that coefficient of friction(COF)decreases with decrease of surface *** the same time,no statistically significant correlation was found between the hydrophobicity of the surface and the value of the friction coefficient.

关键词： biotribology friction articulation contact angle surface texture lubrication

Gradewise Properties of Subgroups and Their Applications

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Algebra Colloquium 2017年第2期24卷 255-266页

作者： Wenbin Guo alexander n. Skiba Department of Mathematics University of Science and Technology of China Hefei 230026 China Department of Mathematics Francisk Skorina Gomel State University Gomel 246019 Belarus

For each finite group E, let O（E） be a binary relation on the set of all subgroups of E. If A and B are subgroups of a finite group G, then we say that the pair （A, B） enjoys the gradewise property （resp., generalized gradewise property） in G if G has a normal series Г：1=G0≤G1≤Gt=Gsuch that for each i=1,...,t,we have （（A∩Gi）Gi-1/BGi-1/Gi-1）∈θ（G/Gi-1）（resp., we have （（A∩Gi）Gi-1/BGi-1/Gi-1）∈θ（G/Gi-1）Using these concepts, we obtain some new characterizations for solubility and supersolubility of finite groups and generalize some known results.

关键词： finite group subgroup functor subgroup bifunctor gradewise property

Finite groups whose n-maximal subgroups are σ-subnormal

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Science China Mathematics 2019年第7期62卷 1355-1372页

作者： Wenbin Guo alexander n. Skiba School of Mathematical Sciences University of Science and Technology of China Hefei 230026 China Department of Mathematics and Technologies of Programming Francisk Skorina Gomel State University Gomel 246019 Belarus

Let σ={σi | i ∈ I} be some partition of the set of all primes P. A set H of subgroups of G is said to be a complete Hall σ-set of G if every member ≠ 1 of H is a Hall σi-subgroup of G, for some i ∈ I, and H contains exactly one Hall σi-subgroup of G for every σi ∈σ(G). A subgroup H of G is said to be:σ-permutable or σ-quasinormal in G if G possesses a complete Hall σ-set H such that HAx= AxH for all A ∈ H and x ∈ G:σ-subnormal in G if there is a subgroup chain A = A0≤A1≤···≤ At = G such that either Ai-1■Ai or Ai/(Ai-1)Ai is a finite σi-group for some σi ∈σ for all i = 1,..., *** Mn n-1 n, then Mn is said to be an n-maximal subgroup of G. If each n-maximal subgroup of G is σ-subnormal(σ-quasinormal,respectively) in G but, in the case n > 1, some(n-1)-maximal subgroup is not σ-subnormal(not σ-quasinormal,respectively) in G, we write mσ(G)= n(mσq(G)= n, respectively).In this paper, we show that the parameters mσ(G) and mσq(G) make possible to bound the σ-nilpotent length lσ(G)(see below the definitions of the terms employed), the rank r(G) and the number |π(G)| of all distinct primes dividing the order |G| of a finite soluble group G. We also give the conditions under which a finite group is σ-soluble or σ-nilpotent, and describe the structure of a finite soluble group G in the case when mσ(G)=|π(G)|. Some known results are generalized.

关键词： finite group n-maximal subgroup σ-subnormal subgroup σ-quasinormal subgroup σ-soluble group σ-nilpotent group