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The effect of the film thickness and doping content of SnO2:F thin films prepared by the ultrasonic spray method

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Journal of Semiconductors 2013年第9期34卷 21-25页

作者： Achour Rahal said Benramache Boubaker Benhaoua VTRS Laboratory Institute of TechnologyUniversity of El-oued 39000Algeria Physics Laboratory Institute of TechnologyUniversity of El-oued 39000Algeria Material Sciences Laboratory Faculty of ScienceUniversity of Biskra 07000Algeria

This paper reports on the effects of film thickness and doping content on the optical and electrical properties of fluorine-doped tin oxide. Tin （Ⅱ） chloride dehydrate, ammonium fluoride dehydrate, ethanol and HC1 were used as the starting materials, dopant source, solvent and stabilizer, respectively. The doped films were deposited on a glass substrate at different concentrations varying between 0 and 5 wt% using an ultrasonic spray technique. The SnO2：F thin films were deposited at a 350 ℃ pending time （5, 15, 60 and 90 s）. The average transmission was about 80%, and the films were thus transparent in the visible region. The optical energy gap of the doped films with 2.5 wt% F was found to increase from 3.47 to 3.89 eV with increasing film thickness, and increased after doping at 5 wt%. The decrease in the Urbach energy of the SnO2：F thin films indicated a decrease in the defects. The increase in the electrical conductivity of the films reached maximum values of 278.9 and 281.9 （Ω.cm）-1 for 2.5 and 5 wt% F, respectively, indicating that the films exhibited an n-type semiconducting nature. A systematic study on the influence of film thickness and doping content on the properties of SnO2：F thin films deposited by ultrasonic spray was reported.

关键词： SnO2 fluoride thin film film thickness TCO ultrasonic spray technique

Preparation of n-type semiconductor SnO_2 thin films

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Journal of Semiconductors 2013年第8期34卷 25-28页

We studied fluorine-doped tin oxide on a glass substrate at 350℃using an ultrasonic spray technique. Tin（Ⅱ） chloride dehydrate,ammonium fluoride dehydrate,ethanol and NaOH were used as the starting material, dopant source,solvent and stabilizer,*** SnO_2：F thin films were deposited at 350℃and a pending time of 60 and 90 *** as-grown films exhibit a hexagonal wurtzite structure and have（101） *** G = 31.82 nm value of the grain size is attained from SnO_2：F film grown at 90 s,and the transmittance is greater than 80%in the visible *** optical gap energy is found to measure 4.05 eV for the film prepared at 90 s, and the increase in the electrical conductivity of the film with the temperature of the sample is up to a maximum value of 265.58（Ω·cm）^（-1）,with the maximum activation energy value of the films being found to measure 22.85 meV,indicating that the films exhibit an n-type semiconducting nature.

关键词： SnO_2:F thin film TCO ultrasonic spray technique

Expressions of Collagen I and III in Mesenchymal Stem Cells Co-cultured with Ligament Fibroblasts

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生物医学工程学杂志 2005年第S1期22卷 75-76页

作者： said SLIMANI LEMTA-UMR 7563 CNRS/INPL/UHP 54500 Vandoeuvre-lès-Nancy France

Surface morphology and electrochemical characterization of electrodeposited Ni-Mo nanocomposites as cathodes for hydrogen evolution

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Chinese Physics B 2015年第10期24卷 559-563页

作者： Elhachmi Guettaf Temam Hachemi Ben Temam said Benramache Laboratoire de Physique des Couches Minces et Applications Université de Biskra

In this work, we study the influences of current density on surface morphology and electrochemical characterization of electrodeposited Ni-Mo. The Ni-Mo composite coatings are deposited on pretreated copper substrates by electrolytic deposition. The Ni-Mo solution is taken from nickel sulfate fluid and ammonium heptamolybdate with 10 g/l. The Ni-Mo composite coatings are deposited at a temperature of 303 K with an applied current density of j dep= 10 A/dm2-30 A/*** find that the corrosion resistance is improved by incorporating Mo particles into Ni matrix in 0.6-M Na Cl solution. From the potentiodynamic polarization curve of electrodeposited Ni-Mo it is confirmed that the corrosion resistance decreases with increasing applied current density. The x-ray diffraction（XRD） analyses of Ni-Mo coatings indicate three phases of Mo Ni4, Mo1.24Ni0.76, and Ni3 Mo phases crystallites of nickel and molybdenum. The scanning electronic microscopy（SEM） tests indicate that Ni-Mo coatings present cracks and pores.

关键词： Ni-Mo electrolytic deposition corrosion resistance potentiodynamic polarization plating current density

Backgating effect in GaAs FETs with a channel–semi-insulating substrate boundary

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Journal of Semiconductors 2014年第3期35卷 33-38页

作者： Ahmed Chaouki Megherbi said Benramache Abderrazak Guettaf Electrical Engineering Department Faculty of Technology University of Biskra Material Sciences Department Faculty of Sciences University of Biskra

This study focuses on modeling the effects of deep hole traps, mainly the effect of the substrate（backgating effect） in a GaAs transistor MESFT. This effect is explained by the existence, at the interface, of a space charge zone. Any modulation in this area leads to response levels trapping the holes therein to the operating temperature. We subsequently developed a model treating the channel substrate interface as an N–P junction, allowing us to deduce the time dependence of the component parameters of the total resistance R ds, the pinch-off voltage V P, channel resistance, fully open R co and the parasitic series resistance R S to bind the effect trap holes H1and H0. When compared with the experimental results, the values of the R DS（t S/ model for both traps show that there is an agreement between theory and experiment; it has inferred parameter traps, namely the density and the time constant of the trap. This means that a space charge region exists at the channel–substrate interface and that the properties can be approximated to an N–P junction.

关键词： traps pinch-off voltage resistance channel substrate interface

Second Order Sliding Mode Control for Discrete Decouplable Multivariable Systems via Input-output Models

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International Journal of Automation and computing 2015年第6期12卷 630-638页

作者： Houda Romdhane Khadija Dehri Ahmed said Nouri Numerical Control of Industrial Processes National Engineering School of Gabes University of Gabes

The problem of the chattering phenomenon is still the main drawback of the classical sliding mode control. To resolve this problem, a discrete second order sliding mode control via input-output model is proposed in this paper. The proposed control law is synthesized for decouplable multivariable systems. A robustness analysis of the proposed discrete second order sliding mode control is carried out. Simulation results are presented to illustrate the effectiveness of the proposed strategy.

关键词： Discrete second order sliding mode control decoupl

Application of the Second Born Approximation to Excitation of Hydrogen Atoms by Protons and Antiprotons Impact

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Chinese Physics Letters 2008年第10期25卷 3635-3638页

作者： Reda S. Tantawi Samia M. said Department of Mathematics Faculty of Science Zagazig University Zagazig Egypt Department of Basic Engineering Sciences Faculty of Engineering Sana'a Universi Sana'a Yemen

We present and compare total cross sections for excitation in collisions of protons and antiprotons with hydrogen atoms in the 2s state. Calculations axe performed in the framework of the second Born approximation, in the energy range of 5-1000 keV. We apply the usual approach of the second Born approximation, which approximates the summation raised by retaining few terms, as well as another approach approximates all energies corresponding to the intermediate states to that corresponding to the initial state. The annihilation effect in the case of the antiproton collision is investigated. We compare the results with the previous theoretical calculations.

关键词： the power-law exponents precipitation durative abrupt precipitation change

Improved MPPT Control Strategy for PV Connected to Grid Using IncCond-PSO-MPC Approach

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CSEE Journal of Power and Energy Systems 2023年第3期9卷 1008-1020页

作者： Nora Kacimi Abdelhakim Idir said Grouni Mohamed Seghir Boucherit Laboratoire de Commande de Processus ENP AlgerAlgiersAlgeria Electrical Engineering Department University of M’silaBP 28000M’silaAlgeria Boumerdes University Boumerdes35000BoumerdesAlgeria.He is now with the Tamaghasset UniversityAlgeria

This paper proposes a new hybrid maximum power point tracking(MPPT)control strategy for grid-connected solar systems based on Incremental conductance—Particle Swarm Optimization and Model Predictive Controller(IncCond-PSOMPC).The purpose of the suggested method is to create as much power as feasible from a PV system during environmental changes,then transfer it to the power *** accomplish this,a hybrid combination of incremental conductance(IncCond)and particle swarm optimization(PSO)is proposed to locate maximum power,followed by model predictive control(MPC)to track maximum power and control the boost converter to achieve high performance regardless of parameter variations.A two-level inverter,likewise,controlled by Model Predictive Control,is employed to inject the PV power *** this application,the MPC is based on minimizing the difference between the reference and prediction powers,which is computed to select the switching state of the *** proposed system is simulated and evaluated in a variety of dynamic conditions using Matlab/*** reveal that the proposed control mechanism is effective at tracking the maximum power point(MPP)with fewer power oscillations.

关键词： DC/DC boost converter grid-connected PV incremental conductance particle swarm optimization and model predictive controller(IncCond-PSO-MPC) maximum power point tracking(MPPT) photovoltaic(PV)

Nonlinear analysis and reliability of metallic truss structures

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Frontiers of Structural and Civil Engineering 2018年第4期12卷 577-593页

作者： Karim BENYAHI Youcef BOUAFIA Salma BARBOURA Mohand said KACHI LaMoMs Laboratory University Mouloud Mammeri of Tizi-Ouzou15000Tizi-OuzouAlgeria C.N.R.S.LSPM-UPR 3407Laboratory Paris13UniversityParisFrance

The present study goes into the search for the safety domain of civil engineering structures. The objective is to show how a reliability-evaluation brought by a mechanical sizing can be obtained. For that purpose, it is necessary to have a mechanical model and a reliability model representing correctly the behavior of this type of structure. It is a question on one hand, to propose a formulation for the nonlinear calculation (mechanical nonlinearity) of the spatial structures in trusses, and on the other hand, to propose or to adapt a formulation and a modeling of the reliability. The principle of Hasofer-Lind can be applied, in first approach, for the reliability index estimation, scenarios and the probability of failure. The made check concerned metallic in truss structures. Finally, some structures are calculated using the method adapted by Hasofer-Lind to validate the probability approach of the reliability analysis.

关键词： modeling nonlinearity mechanical truss probability reliability response surface probability of failure