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Investigation of electrophysical, photo- and gas-sensitive properties of ZnO–SnO_(2) sol–gel fflms

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Journal of Advanced Dielectrics 2024年第1期14卷 42-50页

作者： Irina A.Gulyaeva Alexandra P.Ivanisheva Maria G.volkova victoria Yu.Storozhenko Soslan A.Khubezhov Ekaterina M.Bayan victor v.petrov Research and Education Centre“Microsystem Technics and Multisensory Monitoring Systems”Southern Federal University Russia Department of Chemistry Southern Federal UniversityRussia Department of Physics North-Ossetian State University362025 VladikavkazRussia Department of Physics and Engineering ITMO University191002 PetersburgRussia

Thin nanocomposite fflms based on tin dioxide with a low content of zinc oxide(0.5–5 mol.%)were obtained by the sol–gel *** synthesized fflms are 300–600 nm thick and contains pore sizes of 19–29 *** resulting ZnO–SnO_(2) fflms were comprehensively studied by atomic force and Kelvin probe force microscopy,X-ray diffraction,scanning electron microscopy,and high-resolution X-ray photoelectron spectroscopy *** photoconductivity parameters on exposure to light with a wavelength of 470 nm were also *** study of the photosensitivity kinetics of ZnO–SnO_(2) fflms showed that the fflm with the Zn:Sn ratio equal to 0.5:99.5 has the minimum value of the charge carrier generation time *** of the activation energy of the conductivity,potential barrier,and surface potential of ZnO–SnO_(2) fflms showed that these parameters have maxima at ZnO concentrations of 0.5 mol.%and 1 mol.%.Films with 1 mol.%ZnO exhibit high response values when exposed to 5–50 ppm of nitrogen dioxide at operating temperatures of 200℃ and 250℃.

关键词： Sol–gel method,ZnO–SnO_(2) films gas-sensitive properties surface potential potential barrier conduction activation energy

Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： victor v.Chizhikov Igor Y.Iskusnykh Department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-valle-Anton and Borrell,2022).

关键词： epithelium Figure center

Design of broadband terahertz vector and vortex beams: I. Review of materials and components

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Light(Advanced Manufacturing) 2022年第4期3卷 126-144页

作者： Nikolay v.petrov Bogdan Sokolenko Maksim S.Kulya Andrei Gorodetsky Aleksey v.Chernykh Digital and Display Holography Laboratory ITMO UniversitySt.Petersburg 197101Russia v.I.vernadsky Crimean Federal University Simferopol 295007Russia School of Physics and Astronomy University of BirminghamBirmingham B152TTUK

In this paper,we review the existing approaches for vortex and vector beam shaping and generation in the terahertz frequency *** particular focus of this review is on the possibility of homogeneous topological charge formation in the ultra-wide spectral interval inherent to ultrashort terahertz *** review the available materials and components,analyse proposed and potentially possible solutions for broadband terahertz vortex and vector beam shaping,compare all developed approaches,and put forward a unified concept for constructing passive shapers of such beams from the existing component base.

关键词： Terahertz radiation vortex beams vector beams Achromatic wave plates Broadband terahertz radiation Digital holography Terahertz holography Total internal reflection Metasurface THz liquid crystals Geometric phase

Design of broadband terahertz vector and vortex beams: II. Holographic assessment

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Light(Advanced Manufacturing) 2022年第4期3卷 14-26页

In this paper,we demonstrate the capabilities of the terahertz pulse time-domain holography in visualisation,simulation,and assessment of broadband THz vortex beam formation dynamics upon its shaping by elements of beam converter,and further propagation and *** adding Jones matrix formalism to describe broadband optical elements,we highlight the differences in the spatio-spectral and spatio-temporal structure of the formed vortex and vector beams dependence on the modulator used and visualise their modal *** influence of diffraction field structure from each element in the broadband vortex modulator is revealed in numerical simulation and the formed beams are analysed against the simplified Laguerre-Gaussian beam model.

关键词： Terahertz radiation vortex beams vector beams Achromatic wave plates Broadband terahertz radiation Digital holography Terahertz holography

Call for Papers:“Cultural Economy and the Economisation of Culture in the System of Modern Societies”:The Seventh International Forum on Marxist Aesthetics

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马克思主义美学研究 2017年第2期 18-19页

作者： Alexander v.petrov Wang Jie the Russian-Chinese Center for Comparative Social Economic and Political ResearchesDepartment of Sociology Saint Petersburg State University Zhejiang University the journal Research on Marxist Aesthetics

(Department of Sociology,Saint Petersburg State University;College of Media and International Culture,Zhejiang University)We are pleased to announce the Seventh International Forum on Marxist Aesthetics to be held on October,2018,at the University of ***,*** with the past forums the aim of the next one is to offer a meeting ground

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INCUBATION TIME CONCEPT IN PROBLEMS OF PULSED STRENGTH OF CONTINUA:FRACTURE,CAvITATION,AND ELECTRICAL BREAKDOWN

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INCUBATION TIME CONCEPT IN PROBLEMS OF PULSED STRENGTH OF CO...

Incubation time approach in rock fracture dynamics

祝贺郑哲敏先生八十华诞应用力学报告会

作者： Yuri v.petrov St.-Petersburg State University NIIMMUniversitetsky Prospect28PetrodvoretsSt.-Petersburg199178Russia

Experiments on the dynamic fracture of solids,hquids,conductors,andinsulators that is caused by fast intense actions of environment or directed energy fluxesreveal a number of effects indicating a fundamental difference between the fast dynamicrupture(breakdown)of materials and a similar process under slow quasistatic *** example,one of the basic problems in testing the dynamic-strength properties of ma-terials is associated with the dependence of the limiting characteristics on the duration,amplitude,and growth rate of an external action,as well as on a number of other *** a critical value is a constant for a material in the static case,experimentallydetermined critical characteristics in dynamics are strongly unstable,and as a result,their behavior becomes *** indicated(and some other)features of thebehavior of materials subjected to pulsed actions are common for a number of seeminglyquite different paysical processes,such as dynamic fracture(starting cracks and scab-bing),cavitation in liquids,and electrical breakdown in *** this paper,we analyzeexamples illustrating typical dynamic effects inherent in these *** propose aunified interpretation for the fracture of solids and liquids and electrical breakdown ininsulators using the structural-time approach[1,2]based on the concept of the fractureincubation time.

关键词： pulsed strength incubation time spalling fracture cavitation in fluids electrical breakdown

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Science China(Physics,Mechanics & Astronomy) 2012年第1期55卷 78-85页

作者： SMIRNOv v.petrov Yuri v BRATOv v St.-Petersburg State Transport University 198103 St.-Petersburg Russia St.-Petersburg State University 198504 St.-Petersburg Russia Institute of Problems of Mechanical Engineering Russian Academy of Sciences 199178 St.-Petersburg Russia

The paper is summarizing latest results connected with application of the incubation time approach to problems of dynamic fracture of rock materials. Incubation time based fracture criteria for intact media and media with cracks are discussed. Available experimental data on high rate fracture of different rock materials and incubation time based fracture criteria are used in order to evaluate critical parameters of causing fracture in these materials. Previously discovered possibility to optimize (minimize) energy input for fracture is discussed in connection to industrial rock fracture processes. It is shown that optimal value of momentum associated with critical load in order to initialize fracture in rock media does strongly depend on the incubation time and the impact duration. Existence of optimal load shapes minimizing momentum for a single fracturing impact or a sequence of periodic fracturing impacts is demonstrated.

关键词： incubation time dynamic fracture rocks dynamic strength fracture toughness crack resistance energy and momentum input fracture process optimization

SIMULATION MODEL OF TECHNOLOGICAL MINERAL DRESSING PROCESSES

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International Journal of Modeling, Simulation, and Scientific Computing 2012年第3期3卷 36-42页

作者： NGUYEN vAN CHI A.v.petrov Department of Automated Systems Irkutsk State Technical University Lermontova 83 Irkutsk664074Russian Federation

The authors worked out a simulation model of technological mineral dressing processes,in which two simulations of technological mineral dressing processes methods are used:transformed structural graph method and method of separation *** first method makes it possible to simulate technological mineral dressing processes at the design stage in conditions of feedstock,equipment and control information *** second method is an effective instrument for operating plant simulation at the reengineering *** and economic efficiency evaluations of the mineral dressing plant are appended to the model.

关键词： Simulation mineral dressing structural graph separation characteristics reengineering efficiency

Magnetic and XPS studies of lithium lanthanide tetraphosphates LiLnP_4O_(12)(Ln=Nd,Gd,Er)

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Journal of Rare Earths 2013年第5期31卷 485-489页

作者： D.petrov B.Angelov v.Lovchinov Department of Physical Chemistry Plovdiv University"Paisii Hilendarski" 24 Tsar Asen Str. 4000 Plovdiv Bulgaria Department of Inorganic and Physical Chemistry University of Food Technologies-Plovdiv26 Maritsa Blvd. 4002 Plovdiv Bulgaria Institute of Solid State Physics Bulgarian Academy of Sciences72Tsarigradsko Chaussee Blvd.1784 SofiaBulgaria

Magnetic susceptibilities of flux-grown single crystals of LitnP4012 （Ln=Nd, Gd, Er） were measured in the temperature range of 2-300 K. The compounds were paramagnetic, and obeyed the Curie-Weiss law in the entire temperature interval, without magnetic phase transitions, and with effective magnetic moments close to those of the corresponding free Ln3＋ ions. X-ray photoelec- tron spectroscopy was applied to determine the positions of core-level electrons relative to the Fermi level： Li is; Ln 4f, 5p, 5s, 4d, 3d; P 2s, 2p; O 1s, 2s. The binding energies in these compounds were found slightly shifted compared to the respective values of the same elements.

关键词： lithium lanthanide tetraphosphates single crystals magnetic properties XPS spectroscopy rare earths