The structure of thalicminine

Summary The structure of thalicminine (I) has been established; it is 2, 3, 7-trimethoxy-5, 6-methylenedioxy-10-oxotetradehydronoraporphine. The conversions of thalicmine (IIb) into thalicminine (I) and of thalicminine (I) into dl-thalicmine (IIb) have been effected.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 426–428, 1966     

The structure of fetidine

Summary Fetidine is a binary aporphine-benzyltetrahydroisoquinoline alkaloid. A structural formula for fetidine has been proposed on the basis of the isolation of (+)-laudanosine (IIIa) and (+)-isoboldine (IV) from the degradation of fetidine (I) with sodium in liquid ammonia.The obtaining of (+)-laudanosine and (+)-glaucine has established the absolute configuration of the two asymmetric centers of fetidine.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 1, pp. 43–48, 1966     

Inverse scattering problem for nonstationary Dirac-type systems on the plane

In this paper the forward and inverse scattering problems for the nonstationary Dirac-type systems on the plane are considered. The scattering data for the inverse scattering problem (ISP) is defined and a unique restoration of the potential from the scattering data is proved.     

Raman scattering and Hall effect in layer InSe under pressure

Abstract

Experimental results of Raman scattering, Hall effect and conductivity measurements of ε-InSe crystals at 300K and pressures up to 10.2 kbar are presented. Changes of the shear force constants under pressure were analyzed using a linear-chain model. The decrease of the shear force constants between metallic planes with increasing pressure are explained qualitatively by charge transfer from intralayer to interlayer space. Changes in the slopes of the Hall constant versus pressure and conductivity versus pressure dependence at about 3.5 kbar are explained by the existing representation of InSe as a direct band gap semiconductor.     

Polynomial identities of bicommutative algebras,Lie and Jordan elements

ABSTRACT

An algebra with identities a(bc)?=?b(ac), (ab)c?=?(ac)b is called bicommutative. We construct list of identities satisfied by commutator and anti-commutator products in a free bicommutative algebra. We give criterions for elements of a free bicommutative algebra to be Lie or Jordan.     

Effect of the structure of a graphite target on the parameters of carbon films obtained by the laser plasma method

We have used Raman light scattering and electron paramagnetic resonance methods to study carbon films obtained by laser plasma deposition, using different types of graphite targets. We have established that the films deposited in this way have a diamond-like structure and are a nanostructured composite containing clusters of both sp² and sp³-hybridized carbon. We have shown that an increase in structural perfection of the graphite target causes an improvement in the structure of the carbon films obtained from it and an increase in the content of sp³-hybridized carbon in it. Thermal stimulation of the substrate during application of a coating leads to the same effect. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 4, pp. 539–546, July–August, 2008.     

An inverse problem of finding the time‐dependent diffusion coefficient from an integral condition

We consider the inverse problem of determining the time‐dependent diffusivity in one‐dimensional heat equation with periodic boundary conditions and nonlocal over‐specified data. The problem is highly nonlinear and it serves as a mathematical model for the technological process of external guttering applied in cleaning admixtures from silicon chips. First, the well‐posedness conditions for the existence, uniqueness, and continuous dependence upon the data of the classical solution of the problem are established. Then, the problem is discretized using the finite‐difference method and recasts as a nonlinear least‐squares minimization problem with a simple positivity lower bound on the unknown diffusivity. Numerically, this is effectively solved using the lsqnonlin routine from the MATLAB toolbox. In order to investigate the accuracy, stability, and robustness of the numerical method, results for a few test examples are presented and discussed. Copyright © 2015 John Wiley & Sons, Ltd.     

An inverse diffusion problem with nonlocal boundary conditions

This article considers the inverse problem of identification of a time‐dependent thermal diffusivity together with the temperature in an one‐dimensional heat equation with nonlocal boundary and integral overdetermination conditions when a heat exchange takes place across boundary of the material. The well‐posedness of the problem is studied under some regularity, and consistency conditions on the data of the problem together with the nonnegativity condition on the Fourier coefficients of the initial data and source term. The inverse problem is also studied numerically by using the Crank–Nicolson finite difference scheme combined with predictor‐corrector technique. The numerical examples are presented and discussed. © 2015 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 32: 564–590, 2016