Nb-doped TiO2 thin films deposited by spray pyrolysis method

Undoped TiO2 and Nb-doped TiO2 thin films have been deposited by spray pyrolysis method on ITO/glass substrates. All the as-deposited films are amorphous, as shown by X-Ray Diffraction. Under certain conditions of heat-treatment in air, the films deposited by pyrolysis became pure anatase. The hydrophilic properties of all the films were investigated, and a comparison was made as a function of the heat treatment, and as a function of Nb doping. Contact angles lower then 3 deg. have been obtained, after irradiation times specific for each film

Electrical and optical properties of Transparent Oxide/Metal/Oxide MultilayerFilms Deposited on Glass and PET substrates

Date du colloque : 10/2012International audienc

Osteosynthesis failure after the pedicle subtraction osteotomy for the correction of sagittal spine imbalance

Orthopedics and Traumatology Department "Victor Babeș" University of Medicine and Pharmacy, Timișoara, Romania, Al VIII-lea Congres Naţional de Ortopedie și Traumatologie cu participare internaţională 12-14 octombrie 2016Purpose Pedicle substraction osteotomy (PSO) in the lumbar spine is indicated in the treatment of large sagittal deformities of the lumbar spine. Substantial complications associated with PSO's include pseudarthrosis and mechanical failure. The purpose of the present study was to assess the complications of this procedure and the causes of mechanical complications. Methods Fifteen patients aged between 38 and 79 years (mean age 63.8+/-12.82) were operated between June 2011 and September 2014 for sagittal imbalance by means of one-level PSO. Preoperative and postoperative value of radiological spino-pelvic sagittal parameters were measured. Clinical and radiological evaluations were conducted preoperatively and postoperatively at 6 months and 1 year. Clinical evaluation included intraand postoperative complications. Results Mean pelvic incidence was 54.86 ±11.82º. Lumbar lordosis (LL) was measured to 12.26 ±18.48º preoperatively and increased to 42.73 ±14.05º postoperatively (p<0.05). Mean gain of lordosis after PSO at index level (fig. 2), was calculated to 28 ± 11º [14–41º]. SVA decreased postoperatively from 93.46 ±36.69 mm to 61.73 ±38.68 mm (p<0.05). Several complications (n = 8), including 2 minor (one dural tear with no clinical consequences and one transient radicular deficit) and 6 major with reintervention were observed in our series. Conclusions The main cause of mechanical complications was insufficient sagittal correction. To limit the risk of mechanical complications and to achieve a good sagittal balance, PSO must be associated with additional SPO's or a second corrective surgery to obtain a solid anterior fusion

On the properties of aluminium doped zinc oxide thin films deposited on plastic substrates from ceramic targets

We report on the deposition of Al doped ZnO (AZO) thin films on unheated polyethylene terephthalate (PET) substrates by pulsed laser deposition technique using a UV excimer laser and Al2O3:ZnO ceramic targets (1.5 and 2 wt% Al2O3). The deposited AZO films have been investigated by atomic force microscopy, scanning electron microscopy, X-ray diffraction, and optical spectrophotometry. Films present excellent optical and electrical properties (transmission in the visible range T &gt; 85%; resistivity at room temperature rho = 1.3 x 10(-3) Omega cm) as electrodes for plastic solar cells. A good correlation was found between deposition conditions (laser fluence) and structural, morphological, optical and electrical propertie

Pulsed laser deposited Aluminium Doped zinc Oxide Films on PET Substrates,

Date du colloque : 06/2009</p

The substrate temperature dependent electrical properties of titanium dioxide thin films

Titanium dioxide thin films were obtained by a dc sputtering technique onto heated glass substrates. The relationship between the substrate temperature and the electrical properties of the films was investigated. Electrical resistivity measurements showed that three types of conduction channels contribute to conduction mechanism in the temperature range of 13-320 K. The temperature dependence of electrical resistivity between 150 and 320 K indicated that electrical conductioninthe films was controlled by potential barriers caused by depletion of carriers at grain boundaries. The conduction mechanism of the films was shifted from grain boundary scattering dominated band conduction to the nearest neighbor hopping conduction at temperatures between 55 and 150 K. Below 55 K, the temperature dependence of electrical resistivity shows variable range hopping conduction. The correlation between the substrate temperature and resistivity behaviorisdiscussed by analyzing the physical plausibility of the hopping parameters and material properties derived by applying different conduction models. With these analyses, various electrical parameters of the present samples such as barrier height, donor concentration, density of states at the Fermi level, acceptor concentration and compensation ratio were determined. Their values as a function of substrate temperature were compared. © Springer Science+Business Media, LLC 2009

Photocatalytic properties of Nb doped TiO2 thin films

Date du colloque : 09/2014International audienc

Nb doped TiO2 thin films as photocatalytic materials

Amorphous undoped and Nb-doped films were obtained by the spin coating method. The films have a compact structure, as revealed by scanning electron microscopy, and are very thin, with thickness values under 100 nm. The photocatalytic activity of the films was evaluated by observing the decomposition of an oleic acid solution under UV irradiation, and by studying the change in the optical transmittance of an aqueous solution containing methylene blue, in the presence of the UV-irradiated films. More than 30 h, depending on doping, are needed to recover their initial contact angles before applying oleic acid. The increase of the optical transmittance of the methylene blue solution confirms the photocatalytic degradation of methylene blue on the Nb-doped TiO2 films. X-ray photoelectron spectroscopy studies, performed to detect the presence of the carbon on the irradiated surface of the films, drive to the conclusion that at the surface of the films, even for contact angles close to 0 ∘ , the presence of carbon still can be detected, which demonstrates that hydrophilicity is ruled by a different mechanism than photocatalysis

Universal semantics for the stochastic λ-calculus

We define sound and adequate denotational and operational semantics for the stochastic lambda calculus. These two semantic approaches build on previous work that used an explicit source of randomness to reason about higher-order probabilistic programs