Properties of titanium-containing sol-gel films modified with copper and vanadium oxides

Translated from Steklo i Keramika, No. 1, pp. 4–6, January, 1994.     

Application of an allosteric ternary complex model to the technique of pharmacological resultant analysis

A simple ternary complex model of drug-receptor interaction has been used to extend the procedure of pharmacological resultant analysis, enabling the quantitation of interactions between allosteric modulators and orthosteric antagonists. Equations derived in the theoretical treatment were used to analyse functional data for the interaction between the allosteric modulator gallamine and the orthosteric antagonist scopolamine, with oxotremorine as the agonist, at rat tracheal muscarinic acetylcholine receptors. Quantitative estimates of the affinity of gallamine for the allosteric site (pKz = 4.7) and the extent of negative, heterotropic co-operativity between gallamine and scopolamine (alpha' = 13.1) were obtained. Furthermore, an alternative direct, model-fitting approach, that does not rely on the determination of concentration ratios, was also developed, and yielded similar results. It is suggested that the approach presented in this paper is useful for quantifying interactions between orthosteric antagonists and allosteric modulators, particularly when the extent of co-operativity is low or the modulators possess multiple pharmacological properties, or both.     

Spatial soliton-induced guiding by cross-phase modulation

The authors show that spatial solitons are able to induce the stable guiding of a weak probe beam in a homogeneous Kerr-type nonlinear media through cross-phase modulation (XPM). The modes of the induced waveguide are derived from the propagation equation of the probe. Experiments have been performed in Kerr liquid CS₂, with beams of picosecond duration at infrared and visible wavelengths. Stable guiding of a green probe induced by an IR soliton beam has been demonstrated in several different experimental situations. Induced antiguiding and beam splitting are also reported for pump and probe of perpendicular polarizations. All results are in excellent agreement with numerical simulations of the propagation     

Nanotomography: Ellipsometric Spectral Tomography of Surface Nanostructures Metal–Oxide

General methodological and mathematical aspects of using tomographic approach to reconstructing the inner structure of surface layers and films on the most abundant nonuniformity types characteristic of heterogeneous physico-chemical nanosystems are discussed. Spectral ellipsometric measurement of light reflected from a nonuniform surface nanolayer allows substantiating spectral-tomographic principle and reconstructing the inner structure of the layer by solving an integral equation of the 1st kind. Principles and mathematic fundamentals of ellipsometric spectral tomography are presented, which may be used in nondestructively monitoring the distribution of physico-chemical properties over the bulk of nonuniform metal–oxide surface structures.     

Quecksilberporosimetriemessungen an durch Druckwasserstrahlen beanspruchten Betonproben

Mercury Penetration Technique and Grain Size Analysis of Concrete The paper describes the behaviour of hardened cement paste and concrete under high velocity water jet attack. Using mercury penetration technique and grain size analysis method, the failure performance is identified as a fracture mechanical one. The behaviour of the materials is influenced due to aggregate grains.