Search results for "layer"
showing 10 items of 2667 documents
Evolution of microstructure and related optical properties of ZnO grown by atomic layer deposition.
2013
A study of transmittance and photoluminescence spectra on the growth of oxygen-rich ultra-thin ZnO films prepared by atomic layer deposition is reported. The structural transition from an amorphous to a polycrystalline state is observed upon increasing the thickness. The unusual behavior of the energy gap with thickness reflected by optical properties is attributed to the improvement of the crystalline structure resulting from a decreasing concentration of point defects at the growth of grains. The spectra of UV and visible photoluminescence emissions correspond to transitions near the band-edge and defect-related transitions. Additional emissions were observed from band-tail states near th…
Optical and structural properties of Al 2 O 3 /ZnO nanolaminates deposited by ALD method
2014
International audience; We report on the investigation of optical and structural properties of Al2O3/ZnO nanolaminates. The nanolaminates were deposited on Si and glass substrates by Atomic layer deposition method. Structural properties of nanolaminates were studied by SEM, GIXRD, and AFM. Optical characterization was performed by transmittance and photoluminescence spectroscopy. Complex analysis of monolayer properties was done by ellipsometry. Optical constants for Al2O3 and ZnO monolayer were calculated.
Atomic layer deposition of AlN from AlCl3 using NH3 and Ar/NH3 plasma
2018
The atomic layer deposition (ALD) of AlN from AlCl3 was investigated using a thermal process with NH3 and a plasma-enhanced (PE)ALD process with Ar/NH3 plasma. The growth was limited in the thermal process by the low reactivity of NH3, and impractically long pulses were required to reach saturation. Despite the plasma activation, the growth per cycle in the PEALD process was lower than that in the thermal process (0.4A ° vs 0.7A ° ). However, the plasma process resulted in a lower concentration of impurities in the films compared to the thermal process. Both the thermal and plasma processes yielded crystalline films; however, the degree of crystallinity was higher in the plasma process. The…
Fabrication and characterization of Donor/Acceptor heterojunction organic solar cells
2018
Results of initial development of organic solar cells having the Donor/Acceptor heterojunction structure with and without an exciton blocking layer are reported. Characterization is carried out in AM1.0 condition with 100 mW/cm2 incident optical power density. The best device has the exciton blocking layer and exhibits an open circuit voltage VOC = 0.43 V, a short circuit current density JSC = 2.35 mA/cm2 with a fill factor FF ≈ 50%, an external quantum efficiency (electrons/s over incident photons/s) EQE ≈ 5% and a power conversion efficiency of about 0.5%.
Gradient and Lipschitz Estimates for Tug-of-War Type Games
2021
We define a random step size tug-of-war game and show that the gradient of a value function exists almost everywhere. We also prove that the gradients of value functions are uniformly bounded and converge weakly to the gradient of the corresponding $p$-harmonic function. Moreover, we establish an improved Lipschitz estimate when boundary values are close to a plane. Such estimates are known to play a key role in the higher regularity theory of partial differential equations. The proofs are based on cancellation and coupling methods as well as an improved version of the cylinder walk argument. peerReviewed
Interactions of membranes with coarse-grain proteins: a comparison
2012
We study the interactions between lipid bilayers and rigid transmembrane proteins by Monte Carlo simulations of generic coarse-grain models. Different popular protein models are considered and compared with each other, and key parameters such as the hydrophobicity and the hydrophobic mismatch are varied systematically. Furthermore, the properties of the membrane are manipulated by applying different tensions. The response of the membrane to the insertion of single proteins is found to be mostly generic and independent of the choice of the protein model. Likewise, the orientational distributions of single proteins depend mainly on the hydrophobic mismatch and the hydrophobicity of the protei…
Aircraft measurements of aerosol particles and trace gases over the Southern Baltic Sea during the BALTIC'15 campaign in 2015
2019
During the BALTIC'15 campaign, conducted in August 2015 over the Southern Baltic Sea, trace gasses (CO2/O3/NOy/SO2) and aerosol particles (number concentration of total/non-volatile/Aitken mode/ Accumulation mode/Coarse mode/refractory black carbon, aerosol extinction coefficient, mass concentration of refractory black carbon were measured). Observations were performed on board of the Alfred Wegener Institute research aircraft Polar 5 during 4 flights: - Scientific flight 1 (SF1) 26 August 2015 - Scientific flight 2 (SF2) 28 August 2015 - Scientific flight 3 (SF3) 28 August 2015 - Scientific flight 4 (SF4) 30 August 2015
Melt Processed PCL/PEG Scaffold with Discrete Pore Size Gradient for Selective Cellular Infiltration
2016
In order to develop scaffold able to mimic the natural gradient properties of tissues, biphasic and triphasic approaches were adopted. In this work, polycaprolactone/polyethylene glycol (PCL/PEG) scaffolds were prepared by using a combination of melt mixing and selective leaching without harmful solvents. The method permitted to develop three-layer scaffolds with high control of porosity and pore size. The mechanical properties were evaluated under physiological condition in order to simulate the real conditions of work. Co-culture of osteoblastic and fibroblastic mice cells were carried out in order to study the differential cellular permeation through the different pore size layers.
The importance of psychological variables in the perceived exertion of young football players
2017
Las escalas para medir la percepción del esfuerzo están entre los métodos que han sido utilizados para el control y la evaluación de la carga interna del entrenamiento en deportes de equipo como el fútbol. Debido a su naturaleza psicofisiológica, su registro proporciona información proveniente tanto de indicadores fisiológicos como psicológicos del deportista. Dentro del marco de la Teoría de la Autodeterminación (SDT, Self Determination Theory; Deci & Ryan, 1985; Ryan & Deci, 2017) y de la Teoría de las Metas de Logro (AGT, Achievement Goal Theory; Ames, 1992; Nicholls, 1989), en esta tesis doctoral se estudian tanto las variables contextuales desadaptativas (dimensiones del clima motivaci…
The micro-macro link in understanding sport tactical behaviours: Integrating information and action at different levels of system analysis in sport
2015
Les liens micro-macroscopiques sont centraux dans les sciences du mouvement humain dans la mesure ou ils correspondent aux coordinations et aux echelonnages des comportements moteurs a differents niveaux d’analyse des systemes complexes. Cet aspect de la complexite est un point cle permettant de considerer decision et action comme un comportement de transition a differents niveaux lors de la realisation d’une performance. Les transitions exprimees en termes de bifurcations sont une part importante du mecanisme universel de decision. Les transitions de phase fournissent aussi un moyen de comprendre les liens micro-macro. Dans cet article de synthese, nous developpons un point de vue qui expl…