Polyhedral Cosmic Strings

Quantum field theory is discussed in M\"obius corner kaleidoscopes using the method of images. The vacuum average of the stress-energy tensor of a free field is derived and is shown to be a simple sum of straight cosmic string expressions, the strings running along the edges of the corners. It does not seem possible to set up a spin-half theory easily.Comment: 15 pages, 4 text figures not include

Enzymatic degradation of model cellulose films

Enzymatic degradation of model cellulose films prepared by a spin-coating technique was investigated by ellipsometry. The cellulose films were prior to degradation characterized by ellipsometry, contact angle measurements, ESCA (electron spectroscopy for chemical analysis) and AFM (atomic force microscopy). At enzyme addition to preformed cellulose films an initial adsorption was observed, which was followed by a total interfacial mass decrease due to enzymatic degradation of the cellulose films. The degradation rate was found to be constant during an extended time of hours, whereafter the degradation leveled off. In parallel to the decreased interfacial mass, the cellulose degradation resulted in a thinner and more dilute interfacial film. At long degradation times, however, there was an expansion of the cellulose film. The enzyme concentration affected the degradation rate significantly, with a faster degradation at a higher enzyme concentration. The effects of pH, temperature, ionic strength and stirring rate in the cuvette were also investigated. (c) 2004 Elsevier Inc. All rights reserved

Model cellulose films exposed to H-insolens glucoside hydrolase family 45 endo-cellulase - the effect of the carbohydrate-binding module

The effects of enzyme structure and activity on the degradation of model cellulose substrates were investigated by ellipsometry for the cellulase Humicola insolens GH45. The inactive variant D10N was found to adsorb at the cellulose surface but also to be incorporated into the cellulose films to an extent that depended on pH. For the native protein, the initial adsorption monitored for the inactive variant D10N was followed by enzyme-mediated degradation of the cellulose films. Again, a dependence on pH was found, such that higher pH resulted in slower enzymatic degradation. Removing the carbohydrate-binding module eliminated this pH dependence but also resulted in a decreased adsorption to the cellulose surface, and in a decreased net catalytic effect. (c) 2004 Elsevier Inc. All rights reserved

Brief guide to the nomenclature of inorganic chemistry

This IUPAC Technical Report (PAC-REP-14-07-18) is one of a series that seeks to distil the essentials of IUPAC nomenclature recommendations. The present report provides a succinct summary of material presented in the publication Nomenclature of Inorganic Chemistry – IUPAC Recommendations 2005. The content of this report will be republished and disseminated as a four-sided lift-out document (see supplementary information) which will be available for inclusion in textbooks and similar publications

Nomenclature for boranes and related species (IUPAC Recommendations 2019)

Abstract An appraisal of the current IUPAC recommendations for the nomenclature of boranes and related systems has been undertaken. New developments in the field have been investigated and existing nomenclature systems have been adapted to accommodate these new developments. The principal areas considered are stoichiometric and structural nomenclature (including heteroatom and metal-atom subrogation, as well as substitution of hydrogen), conjoined-cage species, supra-icosahedral systems, and sub-icosahedral non-standard structures. Elements of substitutive, additive, and replacement nomenclature systems have been integrated into individual names to address contentious problems in boron nomenclature that have been around for a long time