Probing the microstructure evolution during the hardening of gypsum by proton NMR relaxometry

Jaffel, Hamouda; Korb, Jean-Pierre; Ndobo-Epoy, Jean-Philippe; Morin, Vincent; Guicquero, Jean-Pierre

doi:10.1016/j.mri.2007.01.056

Cited by 4 publications

(10 citation statements)

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“…It is well known that proton NMR spectroscopy characterizes the proton chemical species within the gypsum crystal [99]. NMR proton relaxometry at low magnetic fields has been used during the setting of plaster, simultaneously varying the water to plaster ratio (w/p) between 0.4 and 1 [18,19]. 2D spin correlation T 1 -T 2 measurements have also been proposed to compare the hydration and microstructure in b-plaster with ground gypsum mineral and the effects of citric acid as an accelerant and retardant, respectively [100].…”

Section: Direct Probing Of the Nano-wettability Of Plaster Pastesmentioning

confidence: 99%

“…13a). The evolution of plaster paste has been probed continuously, without perturbing the system, by using proton NMR transverse relaxometry of mixing water at a fixed magnetic field [18,19]. According to the well-known chemical reactions for hydration, the stoichiometric water to plaster weight ratio is 0.186.…”

Section: Direct Probing Of the Nano-wettability Of Plaster Pastesmentioning

confidence: 99%

“…Systems typically studied by NMRD, and which will be covered in this review, mainly comprise high surface-area microporous materials [13][14][15] chromatographic supports [15,16], heterogeneous catalytic materials [17], plasters [18,19], concretes [20], cement pastes [21], natural microporous organic kerogens and clay minerals in shale oils [22]. Standard NMR techniques at constant magnetic field have been also proposed for probing the molecular dynamics at pore surfaces despite the very low fraction of molecules in a surface layer.…”

Section: Introductionmentioning

confidence: 99%

“…Section 6 presents the basic relaxation equations of nuclear magnetic relaxation dispersion of 1/T 1 in calibrated micropores in turn for aprotic [15] and protic [16] liquids embedded in calibrated pores, while Section 7 outlines the first application of the multiscale NMRD relaxation investigation of microstructure evolution (ageing) of various cement-based materials [20,21]. This section also presents an application of NMRD for probing directly the nano-wettability of plaster pastes under various conditions of preparation [18,19]. Section 8 extends the analysis of NMRD profiles for separating oil and water contributions in real multimodal macroporous petroleum rocks [27], focussing on the separation of the dynamics and wettability of oil and water in the organic and mineral dual microporosity of shale oil rocks [22].…”

Section: Introductionmentioning

confidence: 99%

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Multiscale nuclear magnetic relaxation dispersion of complex liquids in bulk and confinement

Korb

2018

Progress in Nuclear Magnetic Resonance Spectroscopy

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The nuclear magnetic relaxation dispersion (NMRD) technique consists of measurement of the magnetic-field dependence of the longitudinal nuclear-spin-lattice relaxation rate 1/T. Usually, the acquisition of the NMRD profiles is made using a fast field cycling (FFC) NMR technique that varies the magnetic field and explores a very large range of Larmor frequencies (10 kHz < ω/(2π) <40 MHz). This allows extensive explorations of the fluctuations to which nuclear spin relaxation is sensitive. The FFC technique thus offers opportunities on multiple scales of both time and distance for characterizing the molecular dynamics and transport properties of complex liquids in bulk or embedded in confined environments. This review presents the principles, theories and applications of NMRD for characterizing fundamental properties such as surface correlation times, diffusion coefficients and dynamical surface affinity (NMR wettability) for various confined liquids. The basic longitudinal and transverse relaxation equations are outlined for bulk liquids. The nuclear relaxation of a liquid confined in pores is considered in detail in order to find the biphasic fast exchange relations for a liquid at proximity of a solid surface. The physical-chemistry of liquids at solid surfaces induces striking differences between NMRD profiles of aprotic and protic (water) liquids embedded in calibrated porous disordered materials. A particular emphasis of this review concerns the extension of FFC NMR relaxation to industrial applications. For instance, it is shown that the FFC technique is sufficiently rapid for following the progressive setting of cement-based materials (plasters, cement pastes, concretes). The technique also allows studies of the dynamics of hydrocarbons in proximity of asphaltene nano-aggregates and macro-aggregates in heavy crude oils as a function of the concentration of asphaltenes. It also gives new information on the wettability of petroleum fluids (brine and oil) embedded in shale oil rocks. It is useful for understanding the relations and correlations between NMR relaxation times T and T, diffusion coefficients D, and viscosity η of heavy crude oils. This is of particular importance for interpreting T, T, 2D T-T and D-T correlation spectra that could be obtained down-hole, thus giving a valuable tool for investigating in situ the molecular dynamics of petroleum fluids. Another domain of interest concerns biological applications. This is of particular importance for studying the complex dynamical spectrum of a folded polymeric structure that may span many decades in frequency or time. A direct NMRD characterization of water diffusional dynamics is presented at the protein interface. NMR experiments using a shuttle technique give results well above the frequency range accessible via the FFC technique; examples of this show protein dynamics over a range from fast and localized motions to slow and delocalized collective motions involving the whole protein. This review ends by an interpretation of the origin of the proto...

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Section: Direct Probing Of the Nano-wettability Of Plaster Pastesmentioning

confidence: 99%

Section: Direct Probing Of the Nano-wettability Of Plaster Pastesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Multiscale nuclear magnetic relaxation dispersion of complex liquids in bulk and confinement

Korb

2018

Progress in Nuclear Magnetic Resonance Spectroscopy

154

161

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“…The solid plaster is obtained from the hydration of the hemihydrate (CaSO4,1/2H2O) [1][2][3][4], which can be briefly described as the dissolution of the hemihydrate followed by the precipitation of gypsum crystals. This chemical reaction basically takes about 40 min without accelerators [5]. Since the stoichiometric water-toplaster ratio is 0.186 whereas the ratio generally used in gypsum industry lies between 0.6 and 1, i.e.…”

Section: Introductionmentioning

confidence: 99%

The mechanisms of plaster drying

et al. 2015

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International audienceWe show that the drying rate of plaster pastes is significantly lower than that expected for a pure liquid evaporating from a simple homogeneous porous medium. This effect is enhanced by the air flow velocity and the initial solid/water ratio. Further tests under various conditions and with the help of additional techniques (MRI, ESEM, Microtomography) for measuring the drying rate and local characteristics (water content, porosity) prove that this effect is due to the crystallization of gypsum ions below the sample free surface, which creates a dry region and decreases the drying rate by increasing the length of the path the vapor has to follow before reaching the free surface

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Subflorescence and plaster drying dynamics

Seck

Keita

Faure

et al. 2016

Chemical Engineering Science

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The dynamics of plaster drying and the impact of subflorescence on the process are described through Magnetic Resonance Imaging and X-Ray Microtomography measurements. It is shown that crystals deposit around the air-liquid interface the closest to the sample free surface, which induces a recession of this interface within the sample at a rate only depending on the current saturation (water to pore volume ratio). Thus the distribution of crystals deposited during evaporation essentially depends on the history of saturation. The drying dynamics then results from vapor diffusion through the less porous layers of crystal accumulation below the sample free surface. This in particular makes it possible to predict the dramatic decrease of the drying rate after successive imbibition-drying cycles.

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Probing the microstructure evolution during the hardening of gypsum by proton NMR relaxometry

Cited by 4 publications

References 0 publications

Multiscale nuclear magnetic relaxation dispersion of complex liquids in bulk and confinement

Multiscale nuclear magnetic relaxation dispersion of complex liquids in bulk and confinement

The mechanisms of plaster drying

Subflorescence and plaster drying dynamics

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