¹H NMR Cryoporometry Study of the Melting Behavior of Water in White Cement

Abstract

The pore size of white cement samples is studied by the melting behaviour of water confined in it, using

The Role of Titanium Dioxide on the Hydration of Portland Cement: A Combined NMR and Ultrasonic Study

“…A formation of a “shoulder” in the T1 versus hydration time curve is observed at about 5 h for both C97T3 and C100 samples but is more visible in the C100 sample. The formation of this shoulder is known to relate with the w/c ratio and is more pronounced at a higher w/c ratio [ 12 ], related to a second water release originating from the melting of solid substructures, mainly ettringite crystals into monosulfate [ 41 , 42 ]. Although the samples used in this study have the same w/c ratios, C93T7 and C85T15 do not exhibit such a shoulder contrary to C100 and C97T3 samples.…”

“…Until now, several NMR techniques have been reported to provide valuable information on the porosity, pore size distribution and hydration kinetics of cement pastes. Such techniques include NMR cryoporometry [ 11 , 12 ], imaging [ 13 , 14 , 15 ] and diffusion studies [ 16 , 17 , 18 , 19 ]. The most widely used technique to study the porosity and hydration of cement pastes is proton ( 1 H) NMR relaxometry [ 20 , 21 , 22 , 23 ].…”

Some Applications of a Field Programmable Gate Array Based Time-Domain Spectrometer for NMR Relaxation and NMR Cryoporometry

“…All of these techniques are suitable for a wide range of polymers [18,20] and porous materials [18], including porous glass [30,31], zeolites [32], cement [33], clays [18], rock [27,34], wood [35], and biochar and other porous carbons [18,27,36,37]. In polymers, crystalline/amorphous ratios may be measured.…”

In Situ Monitoring of Cement Gel Growth Dynamics. Use of a Miniaturized Permanent Halbach Magnet for Precise 1H NMR Studies

“…Up to now, several NMR studies have been reported that provide valuable information about the sample porosity, pore size distributions, and hydration kinetics of cement pastes. Such techniques include NMR cryoporometry, 18,19 NMR imaging, [20][21][22] and NMR diffusion studies, [23][24][25] where the determination of the water self-diffusion coefficient is directly related to the transport of water in the cement matrix. However, the most widely used technique to study the porosity and hydration of cement pastes is proton NMR relaxometry.…”

“…Up to now, several NMR studies have been reported that provide valuable information about the sample porosity, pore size distributions, and hydration kinetics of cement pastes. Such techniques include NMR cryoporometry, , NMR imaging, − and NMR diffusion studies, − where the determination of the water self-diffusion coefficient is directly related to the transport of water in the cement matrix. However, the most widely used technique to study the porosity and hydration of cement pastes is proton NMR relaxometry. − In this method the molecular motion and the chemical and physical environments of water are probed by measuring the 1 H nuclear spin−lattice ( T 1 ) and spin−spin ( T 2 ) relaxation times of hydrogen nuclei in water molecules.…”