Molecular structure and properties of benzo-12-crown-4 and acetylbenzo-12-crown-4

Conclusion Significant differences were found in the conformational states of B12C4 and acB12C4 in solution, which are capable of affecting the complexation properties and physiological activity of these polydentate ligands.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1051–1055, May, 1988.     

Molecular structure and biological activity of 2,3-[(4-benzoyl)benzo]-15-crown-5

Institute of Chemical Physics and Institute of Physiologically Active Compounds. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 5, pp. 96–102, September–October, 1990.     

An Estimate for the Attraction Domains of Difference Equations with Periodic Linear Terms

We consider the quasilinear systems of difference equations with periodic coefficients in linear terms. We obtain estimates for the attraction domain of the zero solution and establish inequalities for the norms of solutions. The results are stated in terms of Lyapunov-type matrix series.     

Asymptotic Stability of Solutions to Perturbed Linear Difference Equations with Periodic Coefficients

We consider perturbed linear systems of difference equations with periodic coefficients. The zero solution of a nonperturbed system is assumed asymptotically stable, i.e., all eigenvalues of the monodromy matrix belong to the unit disk {||<1}. We obtain conditions on the perturbation of this system under which the zero solution of the system is asymptotically stable and also establish continuous dependence of one class of numeric characteristics of asymptotic stability of solutions on the coefficients of the system.     

Temperature dependence of the quadrupole splitting and μeff for [FeCl2(Dena)4]·DmgH2

Mössbauer spectrometry and magnetochemical methods have been applied to a complex known as catene: -dimethylglyoxime dichlorotetra(N,N-diethylnicotinamide) iron· (II) [FeCl₂(Dena)₄]·DmgH₂, where Dena is N,N,diethylnicotinamide and DmgH₂ is dimethylglyoxime. The compound has a high-spin state for the iron(II) (S=2). The magnetic susceptibility follows the Curie-Weiss law with a small value of , The E_Q=f(T) relation shows that the symmetry of the immediate environment of the iron is less than tetragonal: ₁=190 cm^–1, ₂=490 cm^–1.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, No. 1, pp. 56–60, January–February 1992.     

Structure and properties of diphenylacetylbenzo-12-crown-4

It has been shown by x-ray structural examination and IR spectroscopy that conformations of diphenylacetylbenzo-12-crown-4 in which the lone pairs of oxygen are oriented on opposite sides of the plane of the macrocycle are stabilized in the crystal and in solution. From a comparison with the structure and anticonvulsant activity of benzo-12-crown-4 with those of its acetyl and diphenylacetyl derivatives, it is suggested that a condition for the possition of this type of activity is the presence of a conformation of the macrocycle in which the lone pairs of the three oxygen atoms are located on the same side.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2020–2023, September, 1989.The authors thank N. V. Lukoyanov and G. I. Van'kin for carrying out the biological tests with DPA-B12C4.     

Integrated cellular manufacturing systems design with production planning and dynamic system reconfiguration

This paper presents and analyzes a comprehensive model for the design of cellular manufacturing systems (CMS). A recurring theme in research is a piecemeal approach when formulating CMS models. In this paper, the proposed model, to the best of the authors’ knowledge, is the most comprehensive one to date with a more integrated approach to CMS design, where production planning and system reconfiguration decisions are incorporated. Such a CMS model has not been proposed before and it features the presence of alternate process routings, operation sequence, duplicate machines, machine capacity and lot splitting. The developed model is a mixed integer non-linear program. Linearization procedures are proposed to convert it into a linearized mixed integer programming formulation. Computational results are presented by solving some numerical examples, extracted from the existing literature, with the linearized formulation.