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DOI: 10.1063/PT.3.3052
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93 Citations
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Glasses constitute a widespread form of solid matter, and glass production has been an important human technology for more than 3000 years. Despite that long history, new ways to understand the fundamental physics of glasses continue to emerge.

Commentaires: 13 pages, 5 figures. To appear in the January 2016 issue of Physics Today (in press). Réf Journal: Physics Today 69, 40 (2016)

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DOI: 10.1016/j.foodhyd.2015.06.014
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Structuring wheat gluten proteins into gels with tunable mechanical properties would provide more versatility for the production of plant protein-rich food products. Gluten, a strongly elastic protein material insoluble in water, is hardly processable. We use a novel fractionation procedure allowing the isolation from gluten of a water/ethanol soluble protein blend, enriched in glutenin polymers at an unprecedented high ratio (50%). We investigate here the viscoelasticity of suspensions of the protein blend in a water/ethanol (50/50 v/v) solvent, and show that, over a wide range of concentrations, they undergo a spontaneous gelation driven by hydrogen bonding. We successfully rationalize our data using percolation models and relate the viscoelasticity of the gels to their fractal dimension measured by scattering techniques. The gluten gels display self-healing properties and their elastic plateaus cover several decades, from 0.01 to 10,000 Pa. In particular very soft gels as compared to standard hydrated gluten can be produced.

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DOI: 10.5194/jsss-5-137-2016
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Nuclear magnetic resonance imaging (NMRI) is a powerful tool for biological investigations. Nevertheless, the imaging resolution performance results in the combination of the magnetic field (B0) and the antenna efficiency. This latter one results in a compromise between the size of the sample, the location of the region of interest and the homogeneity requirement. In the context of spinal cord imaging on mice, a ribbon solenoid coil is used to enhance the efficiency of the MRI experiment. This paper details the calculation of the local magnetization contribution to the induced voltage of MRI coils. The modeling is illustrated on ribbon solenoid antennas used in emitter–receiver mode for the study. The analytical model, which takes into account the emitting mode, the receiving step and the imaging sequence, is compared to the measurement performed on a 9.4 T VARIAN MRI apparatus. The efficiency of the antenna, in terms of signal to noise ratio, is significantly enhanced with respect to a commercial quadrature volumic antenna, given a significant advantage for the study of spinal cord injuries.

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DOI: 10.1063/1.4939288
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We study room-temperature performance of micro-Hall magnetic sensors based on pseudomorphic GaAlAs/GaInAs heterostructures. Active areas of our sensors range from 1 to 80 microns. We focus on the smallest detectable magnetic fields in small sensors and perform a systematic study of noise at room temperature in the frequency range between 1 Hz and 100 kHz. Our data are interpreted by the mobility fluctuation model. The Hooge parameter is determined for the applied technology. We show that, independently of the experimental frequency, the ratio of sensitivity to noise is proportional to characteristic length of the sensor. The resolution of $1\, miliGauss/ \sqrt{Hertz}$ is achievable in a $3 \mu$m sensor at room temperature .

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DOI: 10.1021/acs.analchem.5b03584
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We introduce a new estimator of particle size polydispersity for dynamic light scattering data, which quantifies the relative width of the intensity-weighted distribution of diffusion coefficients. Simulated dynamic light scattering data are analyzed to (i) compare the accuracy and precision of the new polydispersity indicator to polydispersity measurements from standard cumulant and moment analysis (MA) fits and (ii) establish for each method the optimum data range for fitting. Although MA is preferable at low polydispersity, the new estimator is the most accurate and precise at intermediate and large polydispersities. Finally, we successfully apply the method proposed here to real data from colloidal particles, microgels, and polymer solutions.

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Ref Arxiv: 1511.07756
DOI: 10.1088/0953-8984/28/7/075201
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We introduce a temporal scheme for data sampling, based on a variable delay between two successive data acquisitions. The scheme is designed so as to reduce the average data flow rate, while still retaining the information on the data evolution on fast time scales. The practical implementation of the scheme is discussed and demonstrated in light scattering and microscopy experiments that probe the dynamics of colloidal suspensions using CMOS or CCD cameras as detectors.

Commentaires: Published in J. Phys.: Cond. Matter. 11 pages, 5 figures + Supporting Data (Python software to implement the method described in the manuscript)

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DOI: 10.1007/s10854-015-3947-6
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In this study, we have used RF-magnetron sputtering to deposit Al-doped ZnO (AZO) nanostructures thin films on poly-ethylene naphthalate (PEN) substrates. The compacted AZO nanopowders with different Al concentrations (0, 1, 2, 3 and 4 at.%), which were synthesized by sol–gel method combined with a supercritical drying process, have been used as targets. Structural, optical and electrical properties of deposited thin films with different Al concentrations have been investigated. X-ray diffraction results indicated that all the deposited thin films have hexagonal wurzite structure with c-axis orientation without any secondary phases. The SEM cross section image of the films revealed very dense columnar nanostructure. The best electrical properties (ρ = 4 × 10−4 Ω cm, µ = 22 cm2 V−1 s−1, and ne = 8 × 1E20 cm−3) were obtained for the AZO samples containing 2 at.% of Al. The thin films show an average transmittance of 80 % with the PEN substrate in the visible region.