Crystallographic classes in a 4-dimensional Minkowski space

On a crystallographic group, a condition of being topologically discrete is imposed which is weaker than is the conventional requirement for an action on space to be discontinuous. Isomorphism classification is given for crystallographic groups in three crystallographic classes in a 4-dimensional Minkowski space, which are defined by unimodular subgroups of the general Lorentz group. In these classes are, respectively, 24, 36, and 68 crystallographic groups. __________ Translated from Algebra i Logika, Vol. 47, No. 1, pp. 31–53, January–February, 2008.     

Use of organosilicon compounds as modifiers of epoxy compositions

Organosilicon compounds used to improve the strength and adhesion properties, as well as the thermal stability, of epoxy compositions are reviewed. Properties of composition on the basis of bisphenol A-based ED-20 resin cured with a KrOOT-1 silicon-containing amine are described.     

One-dimensional motion of inelastic balls. II: 2-Tied quasicycles

Translated fromSibirskiî Matematicheskiî Zhurnal, Vol. 35, No. 5, pp. 1006–1025, September–October, 1994.     

Chemistry of pyridoxine in drug design

Russian Chemical Bulletin - Pyridoxine and its derivatives, pyridoxamine and pyridoxal, are the three main forms of vitamin B6, which play exceptionally important biological roles in living...     

Search for Delayed and Advanced Particles in the Interaction of Ultrahigh-Energy Cosmic Rays with the Earth’s Atmosphere in the Flow of EAS Muons at the MSU EAS Setup

Physics of Atomic Nuclei - The results obtained by studying temporal distributions of particles of energy in excess of 5 GeV in extensive air showers (EAS) of energy above $$10^{15}$$ eV at...     

Determination of constants of the reaction of epoxy model compounds with organic amines in actual conditions

Kinetic studies of the interaction of monoepoxides with primary and secondary monoamines are carried out. It is shown that the reactivity of the epoxide ring of an active modifier depends on the structure during interaction both in bulk and in solvent environment. It was found that the ratio of the constants of the reaction of primary amino groups with an epoxy ring to the constants of the secondary amine is about 2.