Hyperbolic geometry for non-differential topologists

A soft presentation of hyperbolic spaces, free of differential apparatus, is offered. Fifth Euclid's postulate in such spaces is overthrown and, among other things, it is proved that spheres (equipped with great-circle distances) and hyperbolic and Euclidean spaces are the only locally compact geodesic (i.e., convex) metric spaces that are three-point homogeneous.Comment: 14 page

Locally ordered topological spaces

While topology given by a linear order has been extensively studied, this cannot be said about the case when the order is given only locally. The aim of this paper is to fill this gap. We consider relation between local orderability and separation axioms and give characterisation of all connected, locally connected or compact locally ordered Hausdorff spaces. A collection of interesting examples is also offered

Chromatographic analysis of ivabradine on polar, nonpolar and chemically modified adsorbents by HPTLC

AbstractThin-layer chromatography (TLC) was used to evaluate the behavior of ivabradine in various chromatographic systems. The mobile phases used were aqueous (methanol–water and acetonitrile–water) and non-aqueous (methanol–acetonitrile and methanol–dimethyl sulfoxide) in a wide range of concentrations (0–100%, v/v). The stationary phases used were high-performance TLC plates: Kieselgel 60 F254 S, RP-2 F254 S, RP-8 F254 S, RP-18 F254 S, RP-18 WF254 S, Kieselgel 60 CN F254 S, Kieselgel 60 Diol F254 S, and Kieselgel 60 NH2 F254 s; and TLC plates: aluminum oxide 150 F254, cellulose F, and polyamide 11 F254. The usefulness of various mobile and stationary phases in the separation of ivabradine was demonstrated. Retention mechanisms as well as the Soczewiński-Snyder equation are discussed