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各种生产过程最优节能参数的存在性(英文)

宁波大学学报（理工版） 2012年第1期25卷 48-52页

作者： BRATOv v petrov y v vOLKOv G 圣彼得堡国立大学俄罗斯圣彼得堡198504 俄罗斯科学院力学研究所俄罗斯圣彼得堡198504

研究表明,在诸多生产过程中可以优化输入的断裂能量,使加工能耗最小.以一个简单的中心断裂为例,当加截脉冲具有某种特定形态时,施加到样品上引发破裂的能量可以取一个显著的最小值.研究结果显示,优化各种与断裂有关的生产过程,使得能量... 详细信息

研究表明,在诸多生产过程中可以优化输入的断裂能量,使加工能耗最小.以一个简单的中心断裂为例,当加截脉冲具有某种特定形态时,施加到样品上引发破裂的能量可以取一个显著的最小值.研究结果显示,优化各种与断裂有关的生产过程,使得能量消耗最小是可能的.这种优化的可能应用包括钻孔或岩石粉碎过程,此时能耗成本通常占生产成本的最大部分.上述方法可以预测钻孔或研磨机等的最优参数,从而大大降低生产成本.文章第二部分研究了接触作用条件下引发断裂的能量输入行为.考虑一个球型粒子冲击一个半空间靶的情形,接触导致的应力场可用赫兹解来估计.定义了断裂判据之后,即可确定引发断裂的球粒临界速度及相应的临界动能.该动能的大小依赖于加载的持续时间,并十分明显地存在一个最小值.据此可断定,存在一个动态冲击的能量最优模式.

关键词：节能最优工作模式孕育时间脆性断裂岩石

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

Incubation time approach in rock fracture dynamics

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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

Energy of a solid sphere under nonstationary oscillations

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Science China(Physics,Mechanics & Astronomy) 2014年第3期57卷 469-476页

作者： petrov yu. SMIRNOv v. UTKIN A. BRATOv v. St.-Petersburg State University Institute of Problems of Mechanical Engineering Russian Academy of Sciences St.-Petersburg State Transport University

Analytical solution for spherically symmetric nonstationary oscillations of acoustic and elastic solid sphere is *** dependence of potential,kinetic and internal energy of a solid sphere is *** received results are of practical importance for a wide range of problems connected to testing of material dynamic strength parameters and to the problems of optimizing(minimizing)energy needed for fracture of solids.

关键词： nonstationary oscillations analytical solution material dynamics dynamic elastisity kinetic energy potential energy internal energy energy exchange

First results of turbulence investigation on Globus-M2 using radial correlation Doppler reflectometry

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Plasma Science and Technology 2024年第10期26卷 49-55页

作者： A.PONOMARENKO A.yASHIN v.GUSEv E.KISELEv G.KURSKIEv v.MINAEv y.petrov N.SAKHAROv P.SHCHEGOLEv E.TKACHENKO N.ZHILTSOv Peter the Great St.Petersburg Polytechnic University St.Petersburg 195251Russia Ioffe Institute St.Petersburg 194064Russia

The first results of investigation of the turbulence structure using Doppler backscattering(DBS)on the Globus-M2 tokamak are presented.A one-channel DBS system with a variable probing frequency within the 18–26 GHz range was installed to investigate the edge plasma at normalized minor radiiρ=0.9–*** correlation Doppler reflectometry was used to study the changes in turbulence eddies after the LH *** analysis was applied to the phase derivative of complex in-phase and quadrature(IQ)signals of the DBS diagnostic as it contains information about the poloidal plasma rotation *** L-mode,the radial correlation length L_(r)is estimated to be 3 cm and after transition to H-mode reduces to approximately 2 *** modelling in a linear local approximation using code GENE indicates that the instability with positive growth rate at the normalized minor radiusρ=0.75 in L-mode and H-mode on Globus-M2 was the ion temperature gradient(ITG)mode.

关键词： tokamak turbulence Doppler backscattering correlation reflectometry

Ambiguity of Polystyrene Aerosol Beads Properties Found with Mie Spectra Analysis

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光谱学与光谱分析 2020年第1期40卷 324-327页

作者： petrov D v Zhuzhulina E A Crimean Astrophysical Observatory(CrAO RAS)

Broadband Mie scattering is used to determine the parameters of polystyrene aerosol beads in air,such as size and wavelength dependence of refractive *** method consists in the selection of such parameters of the scattering object,which reproduce observed spectrum *** is why it is very sensitive and hence very *** found that there is an ambiguity of polystyrene aerosol beads properties,determined with this *** combinations of polystyrene particle size and its refractive index can give the same position of Mie *** ambiguity leads to an increase in the error in determining the size and refractive index of the *** refined errors are calculated and the way of their reduction is indicated.

关键词： Nanomaterials Mie theory Polystyrene beads Size Refractive index

Spectral Dependence of Quasi-Rayleigh Polarization Leap of Nonspherical Particles:Polystyrene Beads Application

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光谱学与光谱分析 2021年第2期41卷 654-657页

作者： petrov D v Zhuzhulina E A Crimean Astrophysical Observatory(CrAO RAS) 298409 Nauch nyjRussia

Solid particles in Earth’s atmosphere,such as polystyrene beads,are an important factor affecting the processes of absorption and scattering of light in the *** processes affect on the solar energy transfer in the Earth’s atmosphere,consequently they have influence on the regional and global climate changes and atmospheric *** particular,great interest to study the scattering properties of small particles compared with wavelength,because of such particles experience low gravitational settlement and may have long time of life in the *** scattering particle is much smaller than the wavelength of the scattered or absorbed light,this is the case of Rayleigh *** properties of these particles(such as intensity and the degree of linear polarization)at the Rayleigh scattering are simply derived from electromagnetic Maxwell’s *** when the particles are large enough to be comparable with the wavelength,the deviations from Rayleigh scattering law are *** of the clear manifestations of such deviations is the recently discovered quasi-Rayleigh polarization leap of monodisperse spherical *** quasi-Rayleigh polarization leap allows remote sensing of the sizes of distant particles,based on the spectral position of quasi-Rayleigh polarization leap at different phase angles of *** this paper,we studied the effect of the non-sphericity of a scattering polystyrene particle on the magnitude and position of the quasi-Rayleigh polarization *** is established that the non-sphericity shifts the position of the quasi-Rayleigh polarization leap shorter *** is shown that for non-sphericity of particles makes the quasi-Rayleigh polarization leap becomes less ***,it was found,that increasing of the phase angle and degree of non-sphericity shift the quasi-Rayleigh polarization leap position to shorter ***,in the case of not very elongated particles,the quasi-

关键词： Nanomaterials Polarization T-matrix Quasi-Rayleigh polarization leap