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1

Synthesis and characterization of physical properties of the NiO thin films by various concentrations

Maaoui B., Aoun Y., Benramache S., Nid A., Far R., Touati A.

Advances in Materials Science

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2020

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Vol. 20, nr 3(65)

79--87

EN

In this work, nickel oxide was deposited on a glass substrate at by spray deposition technique; the structural, optical and electrical properties were studied at different NiO concentrations (0.05, 0.10 and 0.15 mol.l-1). Polycrystalline NiO films with a cubic structure with a strong (111) preferred orientation were observed at all sprayed films with minimum crystallite size of 11.97 nm was attained of deposited film at 0.1 mol.l-1. However, α-Ni(OH)2 was observed at 0.15 mol.l-1. The NiO thin films have good transparency in the visible region, the band gap energy varies from 3.54 to 376 eV was affected by NiO concentration, it is shown that the NiO thin film prepared at 0.05 mol.l-1 has less disorder with few defects. The NiO film deposited at 0.15 mol.l-1 has the electrical conductivity was 0.169 (Ω.cm)-1.

2

Effect of temperature on the properties of nickel sulfide films performed by spray pyrolysis technique

Gahtar A., Benramache S., Zaouche C., Boukacham A., Sayah A.

Advances in Materials Science

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2020

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Vol. 20, nr 3(65)

36--51

EN

In this work, we have prepared new materials of the nickel sulfide thin films by using the spray pyrolysis technique for promising co-catalyst to improve the photocatalytic performance or superconductivity. The effect of deposition temperature (523, 573 and 623 K) on structural, optical and electrical properties was investigated. The XRD diffraction shows that the prepared nickel sulfide at 523, 573 and 623 K having an orthorhombic, hexagonal and hexagonal structure, which were Ni3S2, Ni17S18 and NiS2, respectively. The minimum value of crystallite size (45,9 nm) was measured of deposited film at 573K. The thin films prepared at 523 and 573 K have an average transmittance is about 20 %. The prepared Ni1S2 thin film at T=623 K has the lowest calculated optical band gap and Urbach energy. The Ni1S2 thin film also has the best calculated of the refractive index and the extinction coefficient. The FTIR spectrums of the nickel sulfide have various bands such as Ni-S, C-H, O-H, N–H and C-S. The maximum electrical conductivity is 4,29x105 (Ω.cm)-1 was obtained at 573K of the Ni17S18. The nickel sulfide thin films sprayed at 573K have good structural, optical and electrical properties.

3

Nusselt Number Correlation of SAH

Chabane F., Moummi N., Benramache S., Bensahal D., Belahssan O.

Journal of Power Technologies

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2013

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Vol. 93, nr 2

100--110

EN

This paper presents the experimentally investigated thermal performance of a single pass solar air heater. The effects of mass flow rate of air on the outlet temperature, Nusselt Number, Reynolds Number, Prandtl Number, heat transfer in the thickness of the solar collector and thermal efficiency were studied. Experiments were performed for the mass flow rates of 0.0108, 0.0145 and 0.0184 kg/s. For this effect was have created a new correlation correspondent of solar air collector with using fins it was written Nu=K1Re^0.939 Pr^0.523 exp(1.2 m) h^(0.0505Pr).The maximum efficiency levels obtained for the 0.0108, 0.0145 and 0.0184 kg/s were 28.63, 39.69 and 55.69% respectively. A comparison of the results of the solar collector without fins shows a substantial enhancement in thermal efficiency.

4

Experimental analysis on thermal performance of a solar air collector with longitudinal fins in a region of Biskra, Algeria

Chabane F., Moummi N., Benramache S.

Journal of Power Technologies

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2013

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Vol. 93, nr 1

52--58

EN

This paper presents a thermal performance of a single pass solar air heater with fins attached was investigated experimentally. Longitudinal fins were used inferior the absorber plate for an increase the heat exchange and uniform the flow fluid in the channel. The effects of mass flow rate of air on the outlet temperature, the heat transfer in a thickness of solar collector and thermal efficiency were studied. Experiments were performed for two air mass flow rates of 0.012 kg/s., Moreover; the maximum efficiency was obtained by using five longitudinal fins and without fins. The maximum efficiency obtained for the 0.012 kg/s with and without fins were 40.02 % and 34.92 %, respectively. Comparison of the results as an effect the solar collector’s with and without fins shows a substantial enhancement in the thermal efficiency.

5

Dynamic Modeling in a Switched Reluctance Motor SRM using Finite Elements

Guettaf A., Chabane F., Arif A., Benramache S.

Journal of Power Technologies

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2013

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Vol. 93, nr 3

149--153

EN

This paper study the dynamic modeling of three phases, 6/4 Switched reluctance motor (SRM). We have studied the models of electromagnetic field using the finite element method (FEM) for calculation flux linkage and static torque. From the modeling have found a nonlinear of dynamic model, the SRM model has been then tested in a matlab/simulink environment, using nonlinear 2D look-up tables created from its calculated flux linkage and static torque data. The simulation studies for hysteresis and voltage control strategies.

6

Correlation with annealing temperature of pure and doped ZnO thin film

Chabane F., Moummi N., Benramache S., Belahssen O., Bensahal D.

Journal of Power Technologies

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2013

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Vol. 93, nr 4

202--206

EN

Transparent conducting pure and doped zinc oxide thin films with cobalt and indium were deposited on glass substrate by ultrasonic spray method. The thin films were deposited at 350 °C and annealed 500 °C. The direct correlation between the difference of the crystallite size (ΔG) and the difference of the Urbach energy (ΔEu) suggests that the crystallites sizes of the films are predominantly influenced by the disorder of the thin films. The crystallites size in the thin films depend by the disorder (less defects), where the minimum disorder confirmed the high crystallinity. The correlation of the conductivity before and after annealing temperature also indicates that the measurement in the electrical conductivity of the films by the optical band gap was equal; it is predominantly influenced by the transition tail width of undoped and doped ZnO thin films. It will be shown that the conductivity of undoped and doped ZnO is directly correlated with the band gap of the host material. The model proposed of pure and doped ZnO thin film with annealing temperature was investigated.