Studies on the burning of micro- and nanoaluminum particle clouds in air

An experimental study has been conducted to determine flame propagation velocities in micro- (6 µm) and nanosized (250 nm) aluminum particle clouds for various concentrations in air. The experimental results show faster flame propagation in nanoparticle cloud with respect to the microparticle flame. Maximum flame temperature has been measured using a high-resolution spectrometer operating in the visible range. Analysis of combustion residual shows that nanoparticle combustion is realized via the gaseous phase. A laminar flame model has been proposed based on this observation. Model parameters have been derived by fitting the experimental results

Biomarkers involved in glioma development in Drosophila melanogaster model

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Diffusion coefficients and local structure in basic molten fluorides: in situ NMR measurements and molecular dynamics simulations.

The local structure and the dynamics of molten LiF-KF mixtures have been studied by nuclear magnetic resonance (NMR) and molecular dynamics simulations. We have measured and calculated the self-diffusion coefficients of fluorine, lithium and potassium across the full composition range around the liquidus temperature and at 1123 K. Close to the liquidus temperature, D(F), D(Li) and D(K) change with composition in a way that mimics the phase diagram shape. At 1123 K D(F), D(Li) and D(K) depend linearly on the LiF molar fraction. These results show that the composition affects the self-diffusion of anions and cations more weakly than the temperature. The activation energy for diffusion was also determined and its value can be correlated with the strength of the anion-cation interaction in molten fluoride salts

Lithium diffusion in lithium nitride by Pulsed-Field Gradient NMR

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Skin formation in adhesive mortars evaluated by MRI and interfacial rheology

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Drosophila melanogaster: a small fly to better understand the biology of glioma

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Strontium incorporation into biomimetic carbonated calcium-deficient hydroxyapatite coated carbon cloth: biocompatibility with human primary osteoblasts

International audienceIt has already been shown that sono-electrodeposition can be used to coat activated carbon fiber cloth (ACC) with calcium phosphates (CaP) and we recently demonstrated that cathodic polarization at-1 V / Hg/Hg2SO4 was the best parameter to obtain a carbonated calcium deficient hydroxyapatite (CDA) coating with optimal uniformity and homogeneity. In the present study, we investigated whether this technique was suitable to dope this carbonated CDA coating by partial substitution with another bivalent cation such as strontium. We show here that a strontium-substituted carbonated CDA coating can be produced and quantitatively controlled up to at least 10 at.%. In this range we demonstrate that the presence of strontium does not modify either the textural or the structural properties of the carbonated CDA. Owing to the well-known effect of both carbonated CDA and strontium in bone formation, the biocompatibility of ACC coated or not with carbonated CDA or with strontium substituted carbonated CDA was tested using primary human osteoblasts. Our data revealed a positive and dose-dependent effect of strontium addition on osteoblast activity and proliferation. In conclusion, we show here that electrodeposition at-1 V is a suitable and easy process to incorporate cations of biological interest into CaP coating