Search results for " interfaces"
showing 10 items of 1158 documents
Cutaneous Recording and Stimulation of Muscles Using Organic Electronic Textiles
2016
International audience; Electronic textiles are an emerging field providing novel and non-intrusive solutions for healthcare. Conducting polymer-coated textiles enable a new generation of fully organic surface electrodes for electrophysiological evaluations. Textile electrodes are able to assess high quality muscular monitoring and to perform transcutaneous electrical stimulation.
The eye-tracking computer device for communication in amyotrophic lateral sclerosis
2013
Objective To explore the effectiveness of communication and the variables affecting the eye-tracking computer system (ETCS) utilization in patients with late-stage amyotrophic lateral sclerosis (ALS). Methods We performed a telephone survey on 30 patients with advanced non-demented ALS that were provisioned an ECTS device. Median age at interview was 55 years (IQR = 48–62), with a relatively high education (13 years, IQR = 8–13). A one-off interview was made and answers were later provided with the help of the caregiver. The interview included items about demographic and clinical variables affecting the daily ETCS utilization. Results The median time of ETCS device possession was 15 months …
Effect of Stiffness on the Micellization Behavior of Model H4T4 Surfactant Chains
2006
The micellization behavior of a series of model surfactants, all with four head and tail groups (H4T4) but with different degrees of chain stiffness, was studied using grand canonical Monte Carlo simulations on a cubic lattice. The critical micelle concentration, micellar size, and thermodynamics of micellization were examined. In all cases investigated, the critical micelle concentration was found to increase with increasing temperature as observed for nonionic surfactants in apolar or slightly polar solvents. At a fixed reduced temperature and increasing chain stiffness, in agreement with previous observations, it was found that the critical micelle concentration decreased and the average…
Preferential localization of Lactococcus lactis cells entrapped in a caseinate/alginate phase separated system.
2013
International audience; This study aimed to entrap bioprotective lactic acid bacteria in a sodium caseinate/sodium alginate aqueous two-phase system. Phase diagram at pH = 7 showed that sodium alginate and sodium caseinate were not miscible when their concentrations exceeded 1% (w/w) and 6% (w/w), respectively. The stability of the caseinate/alginate two-phase system was also checked at pH values of 6.0 and 5.5. Lactococcus lactis subsp. lactis LAB3 cells were added in a 4% (w/w) caseinate/1.5% (w/w) alginate two-phase system at pH = 7. Fluorescence microscopy allowed to observe that the caseinate-rich phase formed droplets dispersed in a continuous alginate-rich phase. The distribution of …
The defined adsorption site of sodium on the TiO2(110)–(1×1) surface
2004
The adsorption site of sodium on the TiO2(1 1 0)–(1 × 1) surface was studied by extended X-ray absorption fine structure. For coverage ranging between 0.25 and 0.5 ML, we find that sodium is on an ‘in-between' site where it is bound to two bridging oxygen atoms at 2.25 Å and one in-plane oxygen atom at 2.40 Å, in full agreement with DFT calculations. At higher coverage the site becomes an hollow site where the sodium atom is equidistant to the three oxygen atoms at 2.30 Å, while metallic sodium clusters are also formed at the surface.
Synthesis and characterisation of pack cemented aluminide coatings on metals
2004
Abstract The exposition of metallic materials to high temperature environments leads to their corrosion because of oxidation or sulphidation. One way to protect such materials is to produce an Al 2 O 3 layer which needs to be continuous enough to limit diffusion of oxygen or metallic elements, and withstand this corrosion. Since a few years, it has been proved that aluminide compounds are one of the most effective materials to achieve this goal. Indeed, they possess sufficient Al and many beneficial mechanical properties when exposed to high temperature conditions to make possible the formation of a protective Al 2 O 3 scale. This study is aimed at the elaboration of iron, nickel and molybd…
Templated growth of smart coatings: Hybrid chemical vapour deposition of vanadyl acetylacetonate with tetraoctyl ammonium bromide
2009
Hybrid aerosol assisted and atmospheric pressure chemical vapour deposition methodology has been utilised to produce thin films of vanadium dioxide from vanadyl acetylacetonate. Tetraoctyl ammonium bromide (TOAB) was used in the aerosol precursor solution. The films were analysed by X-ray diffraction, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy. Their optical and thermochromic behaviour was also determined. It was found that the use of TOAB had a templating effect that led to a halving in the particle size and that this consequently led to a significant decrease in the thermochromic transition temperature of the films to 34 8C.
Crystallization kinetics of amorphous SiC films: Influence of substrate
2005
Abstract The crystallization kinetics of amorphous silicon carbide films was studied by means of X-ray diffractometry (XRD) and transmission electron microscopy (TEM). The films were deposited by radio frequency (r.f.) magnetron sputtering on glassy carbon and single crystalline silicon substrates, respectively. TEM micrographs and XRD patterns show the formation of nano-crystalline β-SiC with crystallite sizes in the order of 50 nm during annealing at temperatures between 1200 and 1600 °C. A modified Johnson–Mehl–Avrami–Kolmogorov (JMAK) formalism was used to describe the isothermal transformation of amorphous SiC into β-SiC as an interface controlled, three-dimensional growth processes fr…
Influence of the electro-optical properties of an a-Si:H single layer on the performances of a pin solar cell
2012
We analyze the results of an extensive characterization study involving electrical and optical measurements carried out on hydrogenated amorphous silicon (α-Si:H) thin film materials fabricated under a wide range of deposition conditions. By adjusting the synthesis parameters, we evidenced how conductivity, activation energy, electrical transport and optical absorption of an α-Si:H layer can be modified and optimized. We analyzed the activation energy and the pre-exponential factor of the dark conductivity by varying the dopant-to-silane gas flow ratio. Optical measurements allowed to extract the absorption spectra and the optical bandgap. Additionally, we report on the temperature dependen…
Low vacuum photo electron emitting thin films
2009
Impact ionisation is a standard procedure to ionise gaseous or vaporisable substances in organic mass spectrometry. In this work, a "softer" ionisation is introduced which seems to be an alternative ion source for reducing collision between substance molecules and the hot internal walls of the box. Through collision mainly found in impact ionisation sources, fragments are built especially from thermally sensitive substances falsifying the spectra. We present here photoelectron emitting materials for the soft ionisation using semiconducting compounds, galliumn nitride (GaN), and a representative of the borides, lanthanum hexaboride (LaB 6 ). They are evaluated by photoelectron spectroscopic …