Extracellular polysaccharides of Bullera alba VKM Y-2141

The intracellular polysaccharides formed byBullera alba VKM Y-2141 have been investigated. This culture synthesizes a xyloglucuronomannan and a xylogalactomannan in a ratio of 8:1. The structure of the xyloglucuronomannan has been established: in it, to the main chain of an -1,3-bound mannan are attached glucuronic acid and xylose residues by -1,2- and -1,4-bonds, respectively. A structural similarity of this polymer to the exoglycans of yeasts of the genusCryptococcus has been noted.Leningrad Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 177–181, March–April, 1990.     

Incorporation of Naphthalocyanine into Shells of Polyelectrolyte Capsules and Their Disruption under Laser Radiation

Different methods have been proposed for the incorporation of a dye, vanadyl tetra-5,14,23,32-phenyl-2,3-naphthalocyanine, into the shells of polyelectrolyte capsules. Capsule preparation conditions have been selected to provide efficient incorporation of the dye and stability of capsules to aggregation. A suspension of the capsules has been irradiated with lasers operating at wavelengths belonging to the near-infrared spectral region. It has been found that the capsules can be disrupted under the irradiation. Continuous and pulsed laser radiations have been shown to have different effects on the capsules.     

Minimizing sequences in optimal control with approximately given input data and the regularizing properties of the Pontryagin maximum principle

Results related to the optimal control theory for systems with approximately given input data are presented. The basic (desired) element in the theory is the minimizing sequence of feasible controls rather than the classical optimal control. Necessary and sufficient conditions for minimizing sequences are established. The regularizing properties of the Pontryagin maximum principle and of minimizing sequences are discussed. Three basic regularization levels are singled out that are characteristic of any optimal control problem. The stability of the optimal value in a problem depending on the constraint parameter is discussed. Illustrative examples are considered in detail.     

Indecomposable Representations of the Superalgebra B(1,2)

Finite-dimensional indecomposable superbimodules over the superalgebra B(1,2) are treated. We propound a method for constructing indecomposable alternative superbimodules over B(1,2) containing a given socle (such can be presented by any irreducible module over B(1,2)). The method is based on adding on the Jordan basis. Also, for the characteristic 3 case, we give examples of Jordan indecomposable superbimodules which are not alternative.     

A new application of derivatives of polychlorobiphenyls and polyethylene glycols

The reaction of congeners of Sovol technical mixture of polychlorobiphenyls with polyethylene glycols was studied. Mixtures of hydroxy and mono(polyethylene glycol)oxy derivatives were obtained. The mixtures synthesized, which are of low hazard, were used as additives to industrial oil to improve its tribological characteristics.

     

Representations of alternative algebras and superalgebras

This paper is a survey of results on representations of alternative algebras and superalgebras. In particular, new results of the authors on the subject are presented.     

Quantum yield and mechanism of singlet oxygen generation via UV photoexcitation of O2-O2 and N2-O2 encounter complexes

The mechanism and spectral dependence of the quantum yield of singlet oxygen O(2)(a (1)Δ(g)) photogenerated by UV radiation in gaseous oxygen at elevated pressure (32-130 bar) have been experimentally investigated within the 238-285 nm spectral region overlapping the range of the Wulf bands in the absorption spectrum of oxygen. The dominant channel of singlet oxygen generation with measured quantum yield up to about 2 is attributed to the one-quantum absorption by the encounter complexes O(2)-O(2). This absorption gives rise to oxygen in the Herzberg III state O(2)(A' (3)Δ(u)), which is assumed to be responsible for singlet oxygen production in the relaxation process O(2)(A' (3)Δ(u), υ) + O(2)(X (3)Σ(g)(-)) → O(2)({a (1)Δ(g)}, {b (1)Σ(g)(+)}) + O(2)({a (1)Δ(g), υ = 0}, {b (1)Σ(g)(+), υ = 0}) with further collisional relaxation of b to a state. This mechanism is deduced from the analysis of the avoiding crossing locations on the potential energy surface of colliding O(2)-O(2) pair. The observed drop of the O(2)(a (1)Δ(g)) yield near spectral threshold for O(2) dissociation is explained by the competition between above relaxation and reaction giving rise to O(3) + O (O + O + O(2)) supposed in literature. The quantum yield of O(2)(a (1)Δ(g)) formation from encounter complex N(2)-O(2) measured at λ = 266 nm was found to be the same as that for O(2)-O(2).