Raman spectroscopic studies on the structure of materials, specially of glasses, ceramics, films and fibres

A survey is given of applications of Raman spectroscopy in materials characterization. The following topics are covered: Analytical characterization of glasses in the system PbO-B₂O₃ and of glasses and ceramics in the system SrO-B₂O₃-Al₂O₃-TiO₂; investigation and discussion of the so-called Boson peak in the Raman spectra of glasses; Raman spectra obtained with a microscope attachment of carbonaceous materials to study the orientation of graphite planes in films and fibres.     

Über algebraische Relationen zwischen additiven und multiplikativen Funktionen

Ohne Zusammenfassung

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Temperature variation of bubble domains in Dy0.3Tm0.7FeO3 mixed orthoferrite

Bubble domain structure in Dy_0.3Tm_0.7FeO₃ mixed orthoferrite was studied between room temperature and 480 K using the Faraday effect. Temperature dependence of the magnetization and domain wall energy density has been determined. Starting from the molecular field theory and one-ion theory of magnetocrystalline anisotropy, expressions describing a temperature dependence of the domain wall energy density in orthoferrites have been derived. In the expression for magnetocrystalline energy, uniaxial as well as cubic anisotropy have been accounted for.     

Indium

Analytical and Bioanalytical Chemistry -     

Validation of high-performance thin-layer chromatographic methods for the identification of botanicals in a cGMP environment

Current Good Manufacturing Practices (cGMP) for botanicals stipulates the use of appropriate methods for identification of raw materials. Due to natural variability, chemical analysis of plant material is a great challenge and requires special approaches. This paper presents a comprehensive proposal to the process of validating qualitative high-performance thin-layer chromatographic (HPTLC) methods, proving that such methods are suitable for the purpose. The steps of the validation process are discussed and illustrated with examples taken from a project aiming at validation of methods for identification of green tea leaf, ginseng root, eleuthero root, echinacea root, black cohosh rhizome, licorice root, kava root, milk thistle aerial parts, feverfew aerial parts, and ginger root. The appendix of the paper, which includes complete documentation and method write-up for those plants, is available on the J. AOAC Int. Website (http://www.atypon-link.com/AOAC/loi/jaoi).