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EARLY PTOLEMAIC COINS FROM THE COLLECTION OF THE STATE HISTORICAL MUSEUM (MOSCOW)

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Journal of Ancient Civilizations 2023年第2期38卷 191-235,250页

作者： svyatoslav v.Smirnov Eugenii v.Zakharov Institute of World History Russian Academy of SciencesMoscowRussia The State Historical Museum MoscowRussia

In 2018,the work of one of the leading experts in numismatics of Hellenistic Egypt Catharine ***’s Coins of the Ptolemaic Empire was out of *** work significantly complements and,in some ways,revises the fundamental ... 详细信息

关键词： details Egypt some

Revealing the nature of optical activity in carbon dots produced from different chiral precursor molecules

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Light(Science & Applications) 2022年第5期11卷 855-867页

作者： Ananya Das Evgeny v.Kundelev Anna A.vedernikova Sergei A.Cherevkov Denis v.Danilov Aleksandra v.Koroleva Evgeniy v.Zhizhin Anton N.Tsypkin Aleksandr P.Litvin Alexander v.Baranov Anatoly v.fedorov Elena v.Ushakova Andrey L.Rogach Center of Information Optical Technologies ITMO UniversitySaint Petersburg 197101Russia Research Park Saint Petersburg State UniversitySaint Petersburg 199034Russia Laboratory of Femtosecond Optics and Femtotechnology ITMO UniversitySaint Petersburg 197101Russia Laboratory of Quantum Processes and Measurements ITMO UniversitySaint Petersburg 197101Russia Department of Materials Science and Engineering and Centre for Functional Photonics(CFP)City University of Hong KongKowloonHong Kong SAR 999077China Shenzhen Research Institute City University of Hong KongShenzhen 518057China

Carbon dots(CDs)are light-emitting nanoparticles that show great promise for applications in biology and medicine due to the ease of fabrication,biocompatibility,and attractive optical *** chirality,on the other hand,is an intrinsic feature inherent in many objects in nature,and it can play an important role in the formation of artificial complexes based on CDs that are implemented for enantiomer recognition,site-specific bonding,*** employed a one-step hydrothermal synthesis to produce chiral CDs from the commonly used precursors citric acid and ethylenediamine together with a set of different chiral precursors,namely,L-isomers of cysteine,glutathione,phenylglycine,and *** resulting CDs consisted of O,N-doped(and also S-doped,in some cases)carbonized cores with surfaces rich in amide and hydroxyl groups;they exhibited high photoluminescence quantum yields reaching 57%,chiral optical signals in the Uv and visible spectral regions,and two-photon *** signals of CDs were rather complex and originated from a combination of the chiral precursors attached to the CD surface,hybridization of lower-energy levels of chiral chromophores formed within CDs,and intrinsic chirality of the CD *** DFT analysis,we showed how incorporation of the chiral precursors at the optical centers induced a strong response in their circular dichroism *** optical characteristics of these CDs,which can easily be dispersed in solvents of different polarities,remained stable during pH changes in the environment and after Uv exposure for more than 400 min,which opens a wide range of bio-applications.

关键词： properties chiral carbon

Spherically Symmetric Problem of General Relativity for an Elastic Solid Sphere

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Journal of Modern Physics 2023年第6期14卷 818-832页

作者： valery v. vasiliev Leonid v. fedorov Russian Academy of Sciences Moscow Russia

The paper is devoted to a spherically symmetric problem of General Relativity (GR) for an elastic solid sphere. Originally developed to describe gravitation in continuum (vacuum, gas, fluid and solid) GR does not provide the complete set of equations for solids and, in contrast to the Newton gravitation theory, does not allow us to study the stresses induced by gravitation in solids, because the compatibility equations which are attracted in the Euclidean space for this purpose do not exist in the Riemannian space. To solve the problem within the framework of GR, a special geometry of the Riemannian space induced by gravitation is proposed. According to this geometry, the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. Such interpretation of the Riemannian space in GR allows us to supplement the conservation equations for the energy-momentum tensor with compatibility equations of the theory of elasticity and to arrive to the complete set of equations for stresses. The analytical solution of the Einstein equations for the empty space surrounding the sphere and the numerical solution for the internal space inside the sphere with the proposed geometry are presented and discussed.

关键词： General Relativity Spherically Symmetric Problem Elastic Sphere

To the Solution of a Spherically Symmetric Problem of General Relativity

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Journal of Modern Physics 2023年第2期14卷 147-159页

作者： valery v. vasiliev Leonid v. fedorov Russian Academy of Sciences Moscow Russia

The paper is devoted to the spherically symmetric problem of General Relativity. Existing solutions obtained by K. Schwarzschild and v. Fock are presented and discussed. A special geometry of the Riemannian space induced by gravitation is proposed. According to this geometry the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. The solution of the Einstein equations for the empty space with this geometry coincides with the solution in Gullstand-Painlever coordinates. In application to the found solution, the problem of the light trajectory deviation in the vicinity of Sun and the problem of escape velocity are discussed.

关键词： General Relativity Spherically Symmetric Problem

Linearized Equations of General Relativity and the Problem of Reduction to the Newton Theory

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Journal of Modern Physics 2020年第2期11卷 221-236页

作者： valery v. vasiliev Leonid v. fedorov Institute of Problems in Mechanics Russian Academy of Sciences Moscow Russia

The paper is concerned with the problem of reduction of the general relativity theory to the Newton gravitation theory for a gravitation field with relatively low intensity. This problem is traditionally solved on the basis of linearized equations of general relativity which, being matched to the Newton theory equations, allow us to link the classical gravitation constant with the constant entering the general relativity equations. Analysis of the linearized general relativity equations shows that it can be done only for empty space in which the energy tensor is zero. In solids, the set of linearized general relativity equations is not consistent and is not reduced to the Newton theory equations. Specific features of the problem are demonstrated with the spherically symmetric static problem of general relativity which has the closed-form solution.

关键词： General Relativity Gravitation Constant Linearized Equations Spherically Symmetric Problem

To the Schwarzschild Solution in General Relativity

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Journal of Modern Physics 2018年第14期9卷 2482-2494页

作者： valery v. vasiliev Leonid v. fedorov Institute of Problems in Mechanics Russian Academy of Sciences Moscow Russia

The paper is concerned with the history of the spherically symmetric static problem solution of General Relativity found in 1916 by K. Schwarzschild [1] [2] which is interpreted in modern physics as the background of the objects referred to as Black Holes. First, the modern interpretation this solution which does not exactly coincide with original solution obtained by K. Schwarzschild is discussed. Second, the basic equations of the original Schwarzschild solution are presented in modern notations allowing us to compare existing and original solutions. Finally, a modification of the Schwarzschild approach is proposed allowing us to arrive at the exact solution of the Schwarzschild problem.

关键词： General Relativity Spherically Symmetric Problem Schwarzschild’s Solution Black Holes

To the Complete Set of Equations for a Static Problem of General Relativity

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Journal of Modern Physics 2019年第12期10卷 1401-1415页

作者： valery v. vasiliev Leonid v. fedorov Institute of Problems in Mechanics Russian Academy of Sciences Moscow Russia

The paper is concerned with the formulation of the static problem of general relativity. As known, this problem is reduced to ten equations for the compo-nents of the Einstein tensor and the solution of these equations is associated with two principal problems. First, since the components of the Einstein tensor identically satisfy four conservation equations, only six of these equations are mutually independent. So, the set of the Einstein equations actually contains six independent equations for ten components of the metric tensor and should be supplemented with four additional equations which are missing in the original theory. Second, for a deformable solid the Einstein tensor is associated with the energy tensor which is expressed in terms of six stresses induced by gravitation. These stresses are not known and the relativity theory does not propose any equations for them. Thus, the static problem of general relativity cannot be properly formulated because the set of governing equations is not complete. In the paper, the problem of completeness of the general relativity governing set of equations is analyzed in application to the spherically symmetric static problem and the proposed approach is further described for the general case. As an example, linearized axisymmetric problem is considered.

关键词： General Relativity Coordinate Conditions Compatibility Stress Equations Spherically Symmetric Problem

Frequency-Concentration Dependence of Optical Activity of a Non-Ideal 1D-Superlattice

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Journal of Modern Physics 2011年第12期2卷 1574-1578页

作者： vladimir v. Rumyantsev Stanislav A fedorov 不详

In the present work the widths of layers constituting the non-ideal superlattice are much bigger then the characteristic scales of space dispersion. In such a case the contribution of individual layers to gyrotropy can be regarded as independed. Thus the corresponding optical quantities can be expressed through the layers’ gyrotropic characteristics. This approach is applied to calculate the specific rotation angle of plane of polarization of light propagating through a nonideal 1D-superlattice, which varies in composition as well as in layers’ width. We carry out numerical calculation of the frequency dispersion of optical activity of a non-ideal superlattice, which includes impurity layers with point defects.

关键词： Light Propagation Non-Ideal 1D-Superlattice Optical Activity Exciton Region of the Spectrum

Optical Rotation of Linearly Polarized Light Propagating through a Nonideal 1D-Superlattice

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Materials Sciences and Applications 2010年第1期1卷 32-35页

作者： vladimir v. Rumyantsev Stanislav A. fedorov 不详

The problem of finding polariton modes (necessary for calculating gyrotropic characteristics) in space-dispersed superlattices is not yet solved. At the same time the specified quantities can be approximately evaluated if the widths of layers comprising a multilayer material are much bigger then the characteristic scales of space dispersion. In such a case the contribution of individual layers to gyrotropy can be regarded as independed. Thus the corresponding optical quantities can be expressed through the layers' gyrotropic characteristics. This approach is applied to calculate the specific rotation angle of plane of polarization of light propagating through a nonideal 1D-superlattice, which varies in composition as well as in layers' width.

关键词： Light Propagation Nonideal 1D-Superlattice Specific Rotation Angle