Transmission electron optical study of ettringite and thaumasite

Autor:	Donald E. Macphee, Stephanie Barnett, Eric E. Lachowski
Rok vydání:	2003
Předmět:	Ettringite Materials science Aluminate Building and Construction law.invention chemistry.chemical_compound Crystallography chemistry Electron diffraction Chemical engineering law Carbonate General Materials Science Thaumasite Electron microscope Selected area diffraction Hydrate
Zdroj:	Cement and Concrete Composites. 25:819-822
ISSN:	0958-9465
DOI:	10.1016/s0958-9465(03)00107-0
Popis:	Selected area electron diffraction studies of ettringite, carbonate ettringite and thaumasite have been made. Ettringite suffers severe dehydration effects in the electron microscope whereas carbonate ettringite and thaumasite are relatively stable and their a dimensions are close to those obtained by XRD. The c dimension of thaumasite is also preserved, but that of carbonate ettringite is reduced to less than half its XRD value by a symmetry change and slight longitudinal shrinkage of the calcium aluminate hydrate columns. This is believed to be the result of the stronger hydrogen bonding of apical water molecules in the columns by carbonate ions, which are not volatile in the conditions experienced in the electron microscope and which stabilises the structure.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::6c456607804f44a906ef94cb7aa72f68 https://doi.org/10.1016/s0958-9465(03)00107-0 Zobrazit plný text záznamu Full Text from ScienceDirect