Study of the Composition of a Precipitate Formed from Solutions for the Synthesis of Cathodic Materials Containing Manganese and Citric Acid

Theoretical Foundations of Chemical Engineering - Cathode materials of lithium-ion batteries can be efficiently and quickly obtained by solution combustion synthesis (SCS) from nitrate solutions of...     

Symbolic Investigation of the Spectral Characteristics of Guided Modes in Smoothly Irregular Waveguides

Programming and Computer Software - This paper considers a homogeneous system of functional equations that occurs when solving a spectral problem the eigenfunctions of which describe guided modes...     

Crystal structure of the low-temperature form of K3PO4

The crystal structure of the low-temperature form of K₃PO₄ has been determined for the first time using neutron diffraction (Rietveld method) and Raman spectroscopy: orthorhombic cell (sp. gr. Pnma, Z = 4), lattice parameters a = 1.12377(2) nm, b = 0.81046(1) nm, c = 0.59227(1) nm. The structure is made up of isolated [PO₄] tetrahedra, with the potassium ions in between.     

Inverse problem of radiative-conductive energy transfer in a plane layer of a selective medium under nonsymmetric heating

Fundamentals of the theory of the nonstationary method of determination of the thermal conductivity of selectively absorbing and radiating materials at high temperatures are discussed. This method is shown to be advantageous over the stationary procedure of solution of inverse and direct problems of radiative-conductive energy transfer.All-Union Correspondence Institute of the Food Industry, Moscow, Russia. Research-Production Amalgamation Khrustal', Gus'-Khrustal'nyi, Russia. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 6, pp. 703–710, December, 1993.     

Formalization of ensuring the information security of an organization

In this paper, we propose an algorithm for solving the problem of ensuring the information security of an organization. The algorithm consists of generating a set of threats aimed at the resources of an organization, generating variants of measures intended to provide protection from these threats, and formulating problems of optimizing the selection of measures intended to ensure information security. The algorithm is used in an expert, automatized information system for decision-making support.     

Application of inclusions for modeling of complex information processes and systems

The notion of inclusion of information systems is introduced. Application of this notion provides the possibility of modeling the third and fourth classes of complex information systems on the set of operational states. Original Russian Text Yu.L. Muromtsev, V.M. Tyutyunnik, 2007, published in Nauchno-Tekhnicheskaya Informatsiya, Seriya 2, 2006, No. 12, pp. 8–11.     

Synthesis of the LnNb7O12 (Ln = La, Ce, Pr) Discrete-cluster compounds

The new compounds CeNb₇O₁₂ and PrNb₇O₁₂, isostructural with LaNb₇O₁₂, have been synthesized and characterized by x-ray diffraction. The structures of the LnNb₇O₁₂ (Ln = La, Ce, Pr) compounds have space group P2₁/c (Z = 4), with lattice parameters a = 10.764(2), 10.743(2), 10.738(4) Å; b = 9.192(2), 9.146(2), 9.137(3) Å; c = 10.313(2), 10.304(2), 10.303(3) Å; and β = 104.25(2)°, 104.31(2)°, and 104.21(3)°, respectively. The reduction in the lattice parameters of LnNb₇O₁₂ in going from La to Pr correlates with the ionic radii of Ln: r(La³⁺) > r(Ce³⁺) > r(Pr³⁺). In the Nd(Sm)-Nb-O systems, phases of stoichiometry LnNb₇O₁₂ have not been obtained.