7,134 research outputs found
Violet dyes of the 1860âs : Hofmann, Britannia, Violet de Paris, Wanklynâs and Crystal violet (1883)
Open Access via the Sage Agreement The authors thank the UK EPSRC National Mass Spectrometry Service Centre for mass spectrometric data and the UK National Crystallography Centre (University of Southampton) for the X-ray data collections. M.J.P. performed all synthesis and obtained the characterisation data and W.T.A.H. solved the crystallographic data sets. Data sets were obtained free of charge from the National Crystallography Centre, Southampton University.Peer reviewedPublisher PD
Investigation of the Transition Reaction of Tobermorite to Xonotlite under Influence of Additives
The objective of the present work was to investigate the transition reaction of the calcium silicate hydrate tobermorite into xonotlite under influence of additives. Tobermorite is the main binding agent in steam hardened building materials and the appearance of xonotlite indicates the progress of hardening and an overcuring of the material. Hydrothermal experiments under addition of sucrose, calcium formate and calcium chloride dihydrate to the main components quartz and lime were done using temperatures of 220°C and a reaction time of 40.5 h. All experiments were performed with powders as well as with pressed educts. The products of all syntheses were analyzed with XRD, SEM/EDX and FTIR. The references as well as the syntheses with calcium chloride dihydrate led to the formation of 11 Ă
tobermorite and xonotlite. The former showed the best results and even synthesis with pressed educts and calcium chloride dihydrate revealed an accelerating effect of the additive. In contrast syntheses with sucrose had the worst reactivity and led to the formation of calcite beside the CSH-phase scawtite. The additive calcium formate was only slightly oppressing the crystallization of tobermorite and favouring the formation of xonotlite. Syntheses with pressed pellets and sucrose or calcium formate showed generally worse results
Synthesis and Structural Characterization of CSH-Phases in the Range of C/S = 0.41 - 1.66 at Temperatures of the Tobermorite Xonotlite Crossover
Calcium-Silicate-Hydrate-phases (CSH-phases) are important binding agents of building materials. The synthesis of CSH phases and their structural characterization was done to investigate the crystallization in dependence of an increasing CaO/SiO2 ratio (C/S ratios) from 0.41 up to 1.66 at temperatures in the crossover region of tobermorite to xonotlite (180â and 230â). Parallel runs with the same C/S ratio but on the one hand with constant mass of quartz and variation of lime and on the other hand under reverse conditions (constant mass of lime but variable amounts of quartz) were performed at both temperatures. The aim was to clarify the connections of crystallization mechanism and kinetics of phase formation with structure, crystallinity and morphology of the CSHâs in the mentioned C/S ratio for both temperatures in the tobermorite-xonotlite crossover region. The parallel experiments with different mass ratios of the educts are important to study the influence of time evaluation of supersaturation within the solution under the peculiarities of the retrograde solubility of lime but accelerated solubility of quartz. The products were characterized by XRD, SEM/EDX, FTIR and 29Si MAS NMR spectroscopy (using the Q-site nomenclature [1]). The experiments could clarify some important connections of crystallization process and the reaction pathway
Liquid chromatographyâmass spectrometry analysis of cationic aniline dyes from the Technical University of Dresden Historical Collection of Dyes
Open Access via the Jisc Sage Agreement Acknowledgements We are grateful to Prof. Dr. Horst Hartmann of the Historische Farbstoffsammlung, Technische UniversitÀt Dresden and to the Chandler museum, New York, for samples to analyse. Declaration of conflicting interests The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding The author(s) received no financial support for the research, authorship, and/or publication of this article.Peer reviewedPublisher PD
60 Jahre internationale MusikquellenerschlieĂung: Das RISM als Instrument der Musikforschung
Vor 60 Jahren begann die Arbeit an dem gröĂten musikbibliographischen Projekt in der Geschichte der Musikforschung: RISM / RĂ©pertoire International des Sources Musicales. Die Idee fĂŒr ein Quellenlexikon, das die musikalische Ăberlieferung weltweit verzeichnet, entstand nach 1945, als der Zweite Weltkrieg viele Quellen zerstört oder verstreut hatte. Die Geisteswissenschaften benötigten in ihren Wissenschaftsbereichen einen â international ausgerichteten â Neubeginn, eine an den Quellen orientierte, ideologiefreie und Kulturen ĂŒbergreifende Zusammenarbeit. Die Realisierung war von Anfang an verknĂŒpft mit dem Aufbau der Vereinten Nationen seit 1947 und steht seither unter der Schirmherrschaft der UNESCO. Die Idee, die Umsetzung und die KontinuitĂ€t des RISM sind Meilensteine fĂŒr die Geistes- und Kulturwissenschaften
Musikhandschriften des Dresdner Schumann-Albums: Neu erschlossen und digitalisiert
Von dem sogenannten Schumann-Album, welches die SĂ€chsische Landesbibliothek 1934 erwarb, sind insgesamt 57 musikalische AlbumblĂ€tter erhalten und bereits digitalisiert. Darunter einige StĂŒcke einer Sammlung von Clara Schumann und auch Kompositionen, die Robert Schumann von Komponisten erhielt
Musikhandschriften des Dresdner Schumann-Albums: Neu erschlossen und digitalisiert
Von dem sogenannten Schumann-Album, welches die SĂ€chsische Landesbibliothek 1934 erwarb, sind insgesamt 57 musikalische AlbumblĂ€tter erhalten und bereits digitalisiert. Darunter einige StĂŒcke einer Sammlung von Clara Schumann und auch Kompositionen, die Robert Schumann von Komponisten erhielt
Untersuchungen zum Kristallisationsverhalten und zur Morphologie von 11 à Tobermorit in AbhÀngigkeit von der ReaktivitÀt der KieselsÀurequelle und dem Ionenbestand der Hydrothermallösung
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