Structural, Optical and Electrical Properties of NiO Nanostructure Thin Film

Nickel oxide was deposited on highly cleaned glass substrates using spray pneumatic technique. The effect of precursor molarity on structural, optical and electrical properties has been studied. The XRD lines of the deposited NiO were enhanced with increasing precursor molarity due to the improvement of the films crystallinity. It was shown that the crystalline size of the deposited thin films was calculated using Debye-Scherer formula and found in the range between 9 and 47 nm. The optical properties have been discussed in this work. The absorbance (A), the transmittance (T) and the reflectance (R) were measured and calculated. Band gap energy is considered one of the most important optical parameter, therefore measured and found ranging between 3.64 and 3.86 eV. The NiO thin film reduces the light reflection for visible range light. The increase of the electrical conductivity to maximum value of 0.0896 (Ω cm) – 1 can be explained by the increase in carrier concentration of the films. A good electrical conductivity of the NiO thin film is obtained due to the electrically low sheet resistance. NiO can be applied in different electronic and optoelectronic applications due to its high band gap, high transparency and good electrical conductivity

Micro structural and Mechanics properties of Steel Nitrided by Plasma

Nitriding treatments of low alloyed steels can be performed only at relatively low temperatures in order to avoid a decrease of corrosion resistance due to nitride layers formation. These conditions promote the formation of the compound layer and diffusion zone, which shows high hardness and good corrosion resistance. In the present paper, the influence of the gas mixture N2-H2 in plasma Nitriding process on the micro structural and mechanical characteristics of 32CDV13 steel samples was evaluated. This nuance is used in manufacturing mechanical pieces that are greatly solicited in fatigue. Plasma Nitriding treatments were performed at temperatures in the range 773 K for 4 h. The modified surface layer of the Nitrided samples consists mainly of the ?’ and ? phases, according to metallographic technique analysis, it seems to be essentially a modification of the austenite matrix. High hardness values are observed in the modified layer with a steep decrease to matrix values

Collector Efficiency by Single Pass of Solar Air Heaters with and without Using Fins

This paper presents the study of heat transfer in a solar air heater by using new design of solar collector. The collector efficiency in a single pass of solar air heater without, and with using fins attached under the absorbing plate has been investigated experimentally. Due to the adding the fins inferior an absorber plate, the desirable effect of increasing the heat transfer coefficient compensates for the undesirable effect of decreasing the driving force (temperature difference) of heat transfer, while the attached fins provide an enlarged heat transfer area. In this study, the absorbing plate of solar collector is attached with fins for further improved performance. The improvements of collector efficiencies in the single pass solar air heaters with, and without fins attached; increase with increasing the mass flow rate, especially for operating at lower air flow rate. Experiments were performed for two air mass flow rates of 0.012 and 0.016 kg/s. Moreover; the maximum efficiency obtained for the 0.012 and 0.016 kg/s with, and without fins were 40.02, 51.50% and 34.92, 43.94% respectively. A comparison of the results of the mass flow rates by solar collector with, and without fins shows a substantial enhancement in the thermal efficiency

Structural Damage Detection by Using Finite Element Method as Function of Length

The work described in this paper involves the effect of length and fibre orientation of the composite damping for comparison with the analytical results. The calculation of laminate damping is performed by use of a strain energy method. The modal analysis of the structure for different loading rates is based on the analytical method used to solve the equation of free vibrations. The difference between strain energies for both cases (damaged and undamaged) are calculated by the finite element method. The structural damping of the different beams is evaluated from these energies. The decrease in frequency for different rates of loading shows the loss of stiffness for all lengths studied

Effect of Iron Doping on Physical Properties of NiO Thin Films

Nickel-iron oxide was deposited on highly cleaned glass substrates using spray pneumatic technique. The effect of iron percentage on structural, optical and electrical properties has been studied. The crystalline size of the deposited thin films was calculated using Debye-Scherer formula and found in the range between 8.8 and 27.6 nm. The optical properties have been discussed in this work. The absorbance (A), the transmittance (T) and the reflectance (R) were measured and calculated. Band gap energy is considered one of the most important optical parameter, therefore measured and found ranging between 3.81 and 3.98 eV. The NiO:Fe thin film reduces the light reflection for visible range light. The increase of the electrical conductivity to maximum value of 0.470 10 – 4 (Ω cm) – 1 for 6 % Fe can be explained by the increase in carrier concentration of the films. A good electrical conductivity of the NiO:Fe thin film is obtained due to the electrically low sheet resistance. NiO:Fe can be applied in different electronic and optoelectronic applications due to its high band gap, high transparency and good electrical conductivity

Structural, Optical and Electrical Properties of NiO Nanostructure Thin Film

Nickel oxide was deposited on highly cleaned glass substrates using spray pneumatic technique. The effect of precursor molarity on structural, optical and electrical properties has been studied. The XRD lines of the deposited NiO were enhanced with increasing precursor molarity due to the improvement of the films crystallinity. It was shown that the crystalline size of the deposited thin films was calculated using Debye-Scherer formula and found in the range between 9 and 47 nm. The optical properties have been discussed in this work. The absorbance (A), the transmittance (T) and the reflectance (R) were measured and calculated. Band gap energy is considered one of the most important optical parameter, therefore measured and found ranging between 3.64 and 3.86 eV. The NiO thin film reduces the light reflection for visible range light. The increase of the electrical conductivity to maximum value of 0.0896 (Ω cm) – 1 can be explained by the increase in carrier concentration of the films. A good electrical conductivity of the NiO thin film is obtained due to the electrically low sheet resistance. NiO can be applied in different electronic and optoelectronic applications due to its high band gap, high transparency and good electrical conductivity

Effect of Annealing in Physical Properties of NiO Nanostructure Thin Film

Nickel oxide was deposited on highly cleaned glass substrates using spray pneumatic technique. The effect of precursor molarity on structural, optical and electrical properties has been studied. The XRD lines of the deposited NiO were enhanced with increasing precursor molarity due to the improvement of the films crystallinity. It was shown that the average of the crystalline size of the deposited thin films was calculated using Debye–Scherer formula and found 46.62 for as-deposited sample and 119.89 nm for the annealed one. The optical properties have been discussed in this work. The absorbance (A), the transmittance (T) and the reflectance (R) were measured and calculated. Band gap energy is considered one of the most important optical parameter, therefore measured and found ranging ranging 3.64 for as-deposited sample and 2.98 eV for the annealed one. The NiO thin film reduces the light reflection for visible range light. The increase of the electrical conductivity to maximum value of 0.09241 (Ωcm)−1 can be explained by the increase in carrier concentration of the films. A good electrical conductivity of the NiO thin film is obtained due to the electrically low sheet resistance. NiO can be applied in different electronic and optoelectronic applications due to its high band gap, high transparency and good electrical conductivity

A Comparative Study the Calculation of the Optical Gap Energy and Urbach Energy in Undoped and Indium Doped ZnO Thin Films

In the present paper, we investigated a new model by theoretical methods; it is based on correlation from the experimental data’s which was used in the calculation the optical gap energy and Urbach energies. These data’s were taken from papers previously published. The choice ZnO thin films and spray only to compare our models with the Indium doping. From obtained relations found that the experimental data and theoretical calculation are in qualitative, which were supported with the variation of solution molarities and Indium doping. We have obtained a high correlation coefficient in the estimation of the band gap energy is higher than 0.96 with compare of Urbach energy is changed from 0.84 to 0.89. The measurements by these new models have agreed with minimum relative errors, it is found in the calculations of optical band gap does not exceed 4 %, and for Urbach energy are smaller than 20 and 10 % for undoped and Indium doped ZnO films, respectively. So that the best estimation was found at the Indium doped ZnO thin with maximum enhancement of minimum errors were limited to 3.5 and 9.7 % for the band gap and the Urbach energies, respectively. The decreases in the relative errors of undoped to Indium doped films can be explained by the fewer defects and less disorder

تخطيط الإنتاج في المؤسسة الصناعية باستعمال بحوث العمليات دراسة حالة مؤسسة صناعات الكوابل - بسكرة

نتيجة للتحولات الجارية في محيط المؤسسة الاقتصادية، والضغوط التي تواجهها، سواء تلك المتعلقة بالمنافسة وما يفرضه عليها المحيط الخارجي، أو ما يتعلق بالندرة وشح الموارد، فقد أصبح بقاء المؤسسة مرهون بقدرتها على البقاء والاستمرارية في النشاط. ودخول المؤسسة الجزائرية اقتصاد السوق يتطلب منها إتباع استراتيجيات تتماشى ومتطلبات هذا الأخير، ومن بين هذه الإستراتيجيات إعادة النظر في مختلف نشاطاتها والرقابة على تكاليفها بهدف تخفيضها ويتأتى هذا باستخدام الأساليب الكمية، والتي من بينها نماذج بحوث العمليات التي تقوم على أساس النمذجة لواقع المؤسسات بغية ترشيد اتخاذ القرار. وقد أثبتت هذه النماذج صلاحيتها ونجاحها في مجال إدارة الأعمال وخاصة إدارة الإنتاج من خلال استخدامها في تخطيط الإنتاج وتحسين النظم الإنتاجية للمؤسسات الصناعية. الكلمات المفتاحية : تخطيط الإنتاج، بحوث العمليات، المؤسسة الصناعية

Etude Comparative du Comportement chimique et tribologique des aciers nitrurés

Ce travail est une étude comparative du comportement à la corrosion et à l’usure des aciers nitrurés par plasma. Le comportement à la corrosion a été évalué par des techniques électrochimiques. Les tests de corrosion ont été effectués dans un milieu acide (HCl 1M ). Les tests tribolodiques ont été réalisés en utilisant un tribomètre pion -disque. La morphologie a été observée au MEB. Les résultats expérimentaux ont montré que la nuance 20MnCr5 nitruré résiste mieux à la corrosion et à l’usure que les autres nuances. La couche de combinaison est plus noble que le substrat mais peut favoriser, par effet galvanique, une corrosion localisée grâce à la porosité