Hindered Water Motions in Hardened Cement Pastes Investigated over Broad Time and Length Scales

Beitrag in einer Fachzeitschrift


Details zur Publikation

Autor(en): Bordallo HN, Aldridge LP, Fouquet P, Pardo LC, Unruh T, Wuttke J, Yokaichiya F
Zeitschrift: Acs Applied Materials & Interfaces
Verlag: AMER CHEMICAL SOC
Jahr der Veröffentlichung: 2009
Band: 1
Heftnummer: 10
Seitenbereich: 2154-2162
ISSN: 1944-8244


Abstract


We investigated the dynamics of confined water indifferent hydrated cement pastes With minimized contributions of capillary water. It was found that the water motions are extremely reduced compared to those of bulk water The onset of water mobility, which was modified by the local environment, was investigated with elastic temperature scans using the high-resolution neutron backscattering instrument SPHERES Using a Cauchy-Lorenz distribution. the quasi-elastic signal observed in the spectra obtained by the backscattering spectrometer was analyzed, leading to the identification of rotational motions with relaxation times of 0 3 ns Additionally, neutron spin echo (NSE) spectroscopy was used to measure the water diffusion over the local network of pores The motions observed in the NSE time scale were characterized by diffusion constants ranging from 0 6 to 1 1 x 10(-9) m(2) s(-1) most likely related to water molecules removed from the interface In summary, our results indicate that the local diffusion observed in the gel pores of hardened cement pastes is on the order of that found in deeply supercooled water Finally, the importance of the magnetic properties of cement pastes were discussed in relation to the observation of a quasi-elastic signal on the dried sample spectra measured using the time-of-flight spectrometer



FAU-Autoren / FAU-Herausgeber

Unruh, Tobias Prof. Dr.
Professur für Nanomaterialcharakterisierung (Streumethoden)


Autor(en) der externen Einrichtung(en)
Australian Nuclear Science and Technology Organisation (ANSTO)
Forschungszentrum Jülich GmbH (FZJ)
Helmholtz-Zentrum Berlin für Materialien und Energie (HZB)
Institute Laue-Langevin (ILL)
Niels Bohr Institute / Niels Bohr Institutet
Polytechnic University of Catalonia / Universitat Politècnica de Catalunya


Zitierweisen

APA:
Bordallo, H.N., Aldridge, L.P., Fouquet, P., Pardo, L.C., Unruh, T., Wuttke, J., & Yokaichiya, F. (2009). Hindered Water Motions in Hardened Cement Pastes Investigated over Broad Time and Length Scales. Acs Applied Materials & Interfaces, 1(10), 2154-2162. https://dx.doi.org/10.1021/am900332n

MLA:
Bordallo, Heloisa Nunes, et al. "Hindered Water Motions in Hardened Cement Pastes Investigated over Broad Time and Length Scales." Acs Applied Materials & Interfaces 1.10 (2009): 2154-2162.

BibTeX: 

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