Interaction of nonylphenyl and tributylphenyl ethylene oxide ionic surfactants with highly soluble cyclodextrin derivatives

The modification of the hydrophobicity of some ethoxylated nonylphenol and tributylphenol surfactants with various soluble -cyclodextrin polymers has been studied by reversed-phase chromatography. Stepwise regression analysis proved that the complex forming capacity of surfactants decreases with increasing diameter of the hydrophobic moiety of surfactants, the properties of the crosslinking agent used for preparation of the polymers has no significant effect on the host-guest interaction, the presence of carboxyl groups in the polymer considerably improved the complex stability.     

Study of the Absorption Characteristics of a Zeolite Support in Normal and Reversed-Phase Thin-Layer Chromatography

JPC – Journal of Planar Chromatography – Modern TLC - The retention behavior of 36 synthetic dyes has been studied in adsorption and reversed-phase TLC on zeolite layers with n-hexane,...     

Fast Winning Strategies in Avoider-Enforcer Games

In numerous positional games the identity of the winner is easily determined. In this case one of the more interesting questions is not who wins but rather how fast can one win. These types of problems were studied earlier for Maker-Breaker games; here we initiate their study for unbiased Avoider-Enforcer games played on the edge set of the complete graph K _n on n vertices. For several games that are known to be an Enforcer’s win, we estimate quite precisely the minimum number of moves Enforcer has to play in order to win. We consider the non-planarity game, the connectivity game and the non-bipartite game.     

Zu einem Satze von S. Bernstein über Minimalflächen im Großen

Ohne Zusammenfassung     

Towards a computer-assisted proof for chaos in a forced damped pendulum equation

We report on the first steps made towards the computational proof of the chaotic behaviour of the forced damped pendulum. Although, chaos for this pendulum was being conjectured for long, and it has been plausible on the basis of numerical simulations, there is no rigorous proof for it. In the present paper we provide computational details on a fitting model and on a verified method of solution. We also give guaranteed reliability solutions showing some trajectory properties necessary for complicate chaotic behaviour.     

Über zweidimensionale reguläre Variationsprobleme der Form ∫∫F(p,q)dxdy=Minimum

Ohne Zusammenfassung     

Various stages of oxidation of chlorite as reflected in the Fe2 + and Fe3 + proportions in the Mössbauer spectra of minerals in Boda Claystone

The construction of the most simple representation coordinated with the physical asymptotic conditions is considered for the Coulomb three-body scattering wave function at energies below the threshold of the three-particle breakup. It is shown that such a representation can be constructed with the use of the well-known solutions of the separable Coulomb two-centre (CTC) problem if the role of the intercentre distance is given to the hyperradius. For the simplest version of the approach (Abramov, J Phys B 41:175201, 2008) the corresponding system of radial differential equations and the statement of the three-body scattering problem for the total angular momentum J?≥?0 are presented.