Zur Axiomatik endlicher Gruppen

Ohne Zusammenfassung     

Uniformly maximumnorm stable difference schemes

Sufficient conditions for maximumnorm stability, uniform in the mesh-widths, of implicit two-level difference schemes with constant coefficients are given. Uniform stability is a necessary and sufficient condition for consistent difference schemes to be convergent, when the mesh-widths are unrelated.     

Zur Axiomatik des Brandtschen Gruppoids

Ohne Zusammenfassung     

Predicting the rate of chemical transport using the flux function method

A systematic approach to the selection of independent variables for a theoretical analysis of the rate of chemical transport is discussed. The methodology is based on the use of the transport flux function, which enables optimum conditions to be found on the basis of a minimum number of the variables most likely to have the greatest effect on the transport rate. A more precise quantitative comparison between experimental and theoretical results can be made by taking into account the effects of convection, uncertainties in thermochemical data, and differences in the diffusion properties of vapour species. The latter effect can lead to a redistribution of components in the vapour, and this may have important consequences in certain CVT processes. The theoretical methodology is exemplified by consideration of transport of CoP₃ in the Co-P-Br system, FeP in the Fe-P-I system, and YIG in the Y-Fe-O-Cl and Y-Fe-O-HCl systems. The complex behaviour revealed would probably have been difficult to rationalize on the basis of experimental studies alone.     

Sea-water neutralization of effluents from the industrial processing of phosphorite. A case study in the practical use of basic knowledge in analytical and marine chemistry

It is shown that the complex reactions involved in the neutralization and dilution of industrial effluents containing SiF₄ and H₂SiF₆ with brackish water can be fully elucidated with the HALTAFALL computer program. The accuracy of the calculations was verified analytically by simple potentiometric titrations     

Synthesis and chromatographic separation of poly(styrene-b-ethylene oxide)

Styrene–ethylene oxide block copolymers prepared through anionic polymerization were successfully separated from the corresponding homopolymers by thin-layer chromatography on cellulose on both an analytical and preparative scale.