Journal of New Technology and Materials

jntm

Description

“Journal of New Technology and Materials”(JNTM) is an international peer-reviewed journal that publishes high quality original works on the Material science s (physics, chemistry and life sciences) and engineering. It covers the aspect of materials science and engineering in all forms, particularly materials associated with new technologies (nanoscience and nanotechnology). JNTM provides a platform for researchers, students and industrialist to submit on-going research and developments in material and technology areas. Authors are solicited to contribute to the JNTM by submitting articles that illustrate research results and projects that describe significant advances in all areas covered by our scientific journal (JNTM). More informations are available on : https://sites.google.com/site/jntmjournal, ....... Citation on Google Scholar: https://scholar.google.fr/citations?user=bNBJ-50AAAAJ&hl=fr


8

Volumes

16

Numéros

203

Articles


Hydrochemical characterization of Gareat-El-Tarf plain groundwaters, northeastern, Algeria

Ouldammar Hanane,  Houha Belgacem, 

Résumé: A hydrochemical study has been conducted on groundwaters of Gareat-El- Tarf plain in order to discriminate the salinity origin. Achieved findings indicate that waters are of medium salinity, with a conductivity of 1618μS/cm. A spatial variation in chemical facies suggests that waters chemistry is influenced by a number of factors such as geology, climate and anthropogenic activity. Waters are bicarbonate-calcic type upstream of the basin and near calcareous outcrops, sulfate-calcic type in the Mio-Plio-Quaternary filling and ultimately become chloride-sodic type on the borders of the Sebkha. Chloride ion crossing with major ions on binary diagrams suggests that waters salinity would be attributed to water-rock interaction characterized by mineral dissolution and precipitation, as well as cation exchange. Chemical tracing by trace elements such as strontium suggests that evaporites dissolution contributes to waters salinity of Gareat-El-Tarf plain. Statistical approach is another tool allowing to classify processes responsible for hydrochemical variability, in function of their significance. The increase in salinity is mainly due to climate aridity.

Mots clés: Hydrochemistry ; salinity ; dissolution; Sebkha; Algeria;


Investigation of biocompatible polymer poly(caprolactone)-chitosan as nanolayer contain vitamin E with Two methods of electrospinning and finishing.

Saeidi Zahra,  Ashjaran Ali, 

Résumé: One of the most necessary vitamins for human's body is vitamin E which many scientists investigated on release. In this study, two new compatible polymers (POLYCAPROLACTONE and CHITOSAN) have used at the same time for creating a nanolayer with this vitamin. Two methods of producing including electrospinning and finishing have studied. For this purpose, various percentages of polycaprolactone and chitosan have combined with vitamin E and produce with two methods. The surface morphology of nanofibers was studied by microscopy (SEM). By using infrared spectrometer (FTIR) the links between vitamin and nanofiber were studied. The effects of drug release and antimicrobial from nanofibers with standard (AATCC100) were measured. Based on the results of tests it was found that nanofiber PCL-chitosan containing vitamin with a ratio of 70-30 and a concentration of 1 gr and 0.3 gr that has produced with electrospinning, was shown the best speed and the best release in compared to concentrations and the other ratios and the speed of electrospinning was more than finishing and it had 81% Antimicrobial effects.

Mots clés: Polymer; Nanofiber; Electrospinning; Drug Delivery; Vitamin E.


Double-diffusive natural convection in an inclined bi-L-shaped layered porous media: Darcy-Brinkman-Forcheimer model

Djezzar Mahfoud,  Latreche Abdelkrim, 

Résumé: In this study, Brinkman–Forchheimer–extended Darcy model of the two dimensional double diffusive natural convection heat and mass transfer generated in an inclined square bi-L-shaped layered porous cavity filled with Newtonian fluid has been investigated numerically. Each porous layer is considered isotropic, homogeneous and saturated with the same fluid. The cavity is heated and salted from below where as the vertical walls are assumed to be adiabatic and impermeable. The physical model for the momentum conservation equation makes use of the Darcy-Brinkman-Forcheimer model, and the set of coupled equations is solved using a finite volume approach. The power-law scheme is used to evaluate the flow, heat and mass fluxes across each of the control volume boundaries. Tridiagonal matrix algorithm with under- relaxation is used in conjunction with iterations to solve the nonlinear discretized equations. An in-house code developed for this study is validated using previous studies. The results are presented graphically in terms of streamlines, isotherms and iso-concentrations. In addition, the heat and mass transfer rate in the cavity is measured in terms of the average Nusselt and Sherwood numbers for various non dimensional parameters including, the buoyancy ratio N and the inclination angle 

Mots clés: Double-diffusive ; Natural convection ; Porous media ; Darcy-Brinkman-Forcheimer model


Propagation caracteristics of interaction of chirped vector soliton trains in birefringent optical fibers with variable coefficients in the presence of third and fourth order dispersion and quintic nonlinearity

Aziez Siham, 

Résumé: This paper presents a numerical study of propagation characteristics of chirped vector soliton trains in birefringent optical fibers with variable coefficients. This study is done using the compact split step Padé scheme (CSSPS), in the presence of third and fourth order dispersion and quintic nonlinearity. We are interested in the interaction of adjacent vector solitons in managed birefringent fibers by changing different parameters such us the chirp and the distance between two adjacent vector solitons. In all cases, the energy of each chirped vector soliton remains conserved.

Mots clés: Vector soliton trains ; Chirped solitons ; Birefringent optical fibers ; Compact split step Padé scheme ; Coupled higher-order nonlinear Schrodinger equations with variable coefficients ; Temporal waveform


Study of Interface Trapped Charges effect on Performance of Junction Less Trial Material Cylindrical Surrounding-Gate MOSFETs

Fairouz Lagraf,  Djamil Rechem,  Kamel Guergouri, 

Résumé: Interface trapped charges effect on the performance of Junction Less-Trial Material Cylindrical Surrounding-gate MOSFETs (JLTMCSG-MOSFETs) has been studied. An analytical model has been used for this purpose, it is based on solving the two-dimensional Poisson’s equation in cylindrical coordinates. The device performance has been investigated as a function of surface potential, electrical field, drain induced barrier lowering (DIBL), subthreshold Slope (SS) and threshold voltage (Vth). The obtained results show that the performance of the device was improved when using the trial material gate with different work functions and interface trapped charges. This study confirms that the analytical model used is useful not only for circuit simulations, but also for device design and optimization

Mots clés: Surrounding-gate MOSFET; Gate-Trial-material; Junctionless transistor; Trapped charges


Investigation of Temperature Anisotropy in Highly-Magnetized Plasma

Amel Benahmed,  Abdelaziz Sid, 

Résumé: We investigate the temperature anisotropy in highly-magnetized plasma within the framework of kinetic theory. We explicitly calculate the electronic distribution function for a magnetized plasma, taking into account electron-ion (e-i) collisions. The basic equation in this investigation is the Fokker-Planck (F-P) equation, where some justified approximations for fusion and astrophysical magnetized plasmas are used. By computing the second moment of this distribution function, we have expressed the electron temperatures in the parallel direction as well as in the plane perpendicular to the magnetic field. We show that the temperature is anisotropic and that this anisotropy is due to a competition between the magnetic field and the collision effects. We also present the numerical results and interpret them for illustration. Our theoretical analysis is applicable in wave and instability studies in fusion and astrophysical plasma, particularly in magnetized inertial fusion (MIF) scheme.

Mots clés: magnetic thermonuclear fusion ; magnetized plasma ; plasma kinetic theory ; Coulomb collision in plasma


Structural, Electronic and Magnetic Properties of quaternary Heusler compounds CoYFeZ and CoYMnZ (Z = Si, Ge, Ga and Al): An ab-initio Study

Torrichi Mohamed, 

Résumé: We have studied electronic and magnetic structural properties of Quaternary Heusler alloys CoYXZ where X is a transition metal with 3d electrons (X=Fe and Mn) and Z is the main group element (Z = Si, Ge, Ga and Al). These calculations have been carried out via ab-initio simulations based on density functional theory (DFT) approach. We have explored the most stable structure among these materials in three different atomic arrangements (type-1, type-2, type-3). The structural stability of these compounds has studied from the calculation of their cohesion energy. The type-1 structure is found energetically more stable. According to our study, the quaternary compound CoYMnGa and CoYMnAl proves to be a half-metal ferromagnetic with a total magnetic moment of 4μB. While the quaternary compounds, CoYMnGe and CoYFeZ (Z=Si, Ge and Ga) seem to be not ferromagnetic, with zero point magnetic. Whereas, CoYMnSi, CoYMnGe and CoYFeAl are found as a ferromagnetic with magnetic moment of 1.91μB, 2.90μB and 4.29μB respectively. In addition, it is also divulged that half-metallicity in these compounds is closely related to arrangements of magnetic atoms in the structure of the Heusler. The magnetization of the compounds CoYFeZ and CoYMnZ comes mainly from the 4d electrons the of Yttrium (Y) atom and the 3d electrons of the Fe and Mn atoms.

Mots clés: : Quaternary Heusler alloy, Half-metallic ferromagnetism, Electronic structures, Density functional theory.


A Hybrid Optimization Approach to Interaction Parameter Identification in thermodynamic model problems

Merzougui Abdelkrim,  Regabe Slimane, 

Résumé: The interaction parameter identification problem in thermodynamic models is an important requirement and a common task in many areas of chemical engineering because these models form the basis for synthesis, design, optimization and control of process. For bad starting values the use gradient based result in local optimal solutions. To overcome this drawback, a global optimization approach, Simulated Annealing(SA) and genetic algorithm(GA), has been coupled with a Nelder-Mead Simplex(NMS) method. To improve the accuracy of the interaction parameter estimate. The experimental ternary LLE data for extraction of 1-propanol from water with n-hexane were considered in the NRTL and UNIQUAC activity coefficient model. In conclusion, the different obtained results of the prediction of liquid–liquid equilibrium are compared. These results were obtained to justify that the process of optimization recommended is very practical to estimate the interaction parameters of this ternary system.

Mots clés: hybrid optimization approach, genetic algorithm, simulated annealing, parameter estimation


The Effects of Electromagnetic stirring on Microstructure and Properties of γ-TiAl based Alloys Fabricated by Selective Laser Melting Technique.

Ismaeel Adam,  Cunshan Wang, 

Résumé: The γ-TiAl based Ti-Al-Mn-Nb alloys were fabricated by selective laser melting (SLM) on the TC4 substrate. The effects of electromagnetic on microstructure and properties of the alloy were investigated in detail. The results reveal that the alloy without electromagnetic stirring EMS consist of γ-TiAl phase with tetragonal structure and α2-Ti3Al phase with hcp structure, while the alloy with applied electromagnetic stirring EMS consist of γ-TiAl, α2-Ti3Al and α-Ti with hcp structure, and the morphological structure for the alloy without EMS exhibits near lamellar structure and the alloy with EMS shows duplex structure, the alloy without EMS shows higher microhardness and wear resistance, and the values decrease with applied EMS.

Mots clés: selective laser melting ; γ-TiAl based alloys ; microstructure ; properties ; electromagnetic stirring


The impact of wall emissivity on the thermal and dynamic behavior of an air channel integrated into the roof

دليلة عبابسة, 

Résumé: Because roofs provide a large area to collect solar energy, they can be exploited to arrive at an architectural element that can act as a solar collector and participate in the improvement of thermal comfort. in this axis and in order to show the importance of radiative exchanges in thermosyphon systems and the choice of roofing construction materials; a 3D numerical study is carried out on the natural convection coupled with radiative exchanges in an inclined air channel (using the commercial computational fluid dynamics software FLUENT). Emissivity values tested correspond to those of some building materials. From our results we affirm that the emissivity of the external roofing affects the dynamic and thermal behavior of the channels integrated under the roof. So a good choice of material roofing is recommended in order to getting a maximum air heating by solar radiation.

Mots clés: Air conditioning, channel, natural convection, radiative heat transfer, roof solar collectors,


Growth rate influence on indium oxide thin films grown by an ultrasonic spraytechnique.

Attaf Abdallah,  Azizi Rahil,  Saidi Hanane,  Benkhetta Youcef,  Bouhaf Kherkhachi Imane,  Attaf Nadir,  Dahnoun Mohamed, 

Résumé: Indium oxide (In2O3) thin films have been grown prosperously on glass substrates by an ultrasonic spray CVD process. The structural, morphological, optical and electrical studies of the films with controlled growth rate induced during elaboration by changing the solution flow rate from 20 to 60 mL/h.The X-ray diffraction (XRD) exhibit that the films are polycrystalline with centered cubic structure, whereas the predominant plane in the films change from (222) to (400) plane. The crystallite size of the films slightly increases with the increase of growth rate where it is varied between 26 and 32 nm.UV-Visible spectroscopy show that the average transmittance is about 80% in the visible region. The optical band gap decreases with an increase of the growth rate from 3.93 to 3.62 eV. Where the high value of band gap can be correlated with the preferential orientation of the (222) plane.The electrical resistivity decreases with the increase of the growth rate in the range of 20 - 5.5 (10-2Ω Cm ).From these results we can say that the indium oxide thin films have a promising properties which make them applicable in the photovoltaic field.

Mots clés: Thin films, Indium oxide, Ultrasonic Spray, Growth rate, Electrical properties.


Heat transfer study in binary alloys solidification Pb-Sn and Pb-Sb

عدوان سميرة,  كربوب عبدالحق,  بلباشا الجمعي, 

Résumé: Simulation of solidification processes has been of interest for a number of years not only because of its scientific value in understanding pattern formation in nature but also because of its importance in many technological applications. The classical Stefan problem is well accepted for modeling the solidification of pure materials and alloys. The two-dimensional model is based on the resolution of heat transfer equation, including the latent heat term. For solving this equation a finite volume method was used. The obtained model from solving the heat transfer equation has lead results for the temperature changes over cooling time for Antimony-Lead and Lead-Tin alloys at various compositions. The obtained cooling curves were compared with the literature results, and they show a good agreement.

Mots clés: Solidification ; Liquid/solid interface. ; Growth morphologies; ; Growth morphologies. ; Nucleation ; Heat transfer


Growth and properties of SnO2 thin films obtained by spray pyrolysis technique

Bendahmane Bouteina,  Touidjen Nour El Houda,  Mansour Farida, 

Résumé: SnO2 (Tin oxide) metal oxide is considered as one of the most investigated II-VI semiconductor in modern microelectronic technology. Several techniques have been used to deposit SnO2 thin films. Among them, spray pyrolysis has proved to be simple, inexpensive and allows the control of many films parameters. In this work, various parameters of the spray pyrolysis technique are optimized to obtain SnO2 thin films. The starting solution molarity M and the deposition temperature Td are fixed at 0.075 M, 0.1 M and Td=350°C, 400°C, respectively. To investigate the films properties, structural, morphological and optical characteristics using X-ray Diffractometry (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDX), Atomic Force Microscopy (AFM) and UV-Visible spectrophotometry are studied respectively. XRD measurements show that SnO2 thin deposited films are polycrystalline with a typical tetragonal structure, except the 350°C-0.075 M film, which shows a beginning of crystallization. SEM and AFM micrographs reveal rough and porous films surfaces with an agglomeration effect of nanoparticles that do not exceed 20 nm. EDX analysis confirms the chemical composition of pure SnO2. Optical characterization shows that absorption peaks decrease strongly from near UV to visible wavelength while a slow decrease of absorption is observed in the visible-IR range. Moreover, a large band gap Eg for all deposited films is estimated.

Mots clés: Spray pyrolysis ; SnO2 ; XRD ; SEM ; AFM ; UV-Vis


Structural Characterization of Sol Gel-Synthesized ZnO Nano Powders With Different Sources of Al Doping

Mahcene Fatima,  Chari Abdelhamid,  Hioual Ouided,  Belabed Naoual,  Kasouit Samir, 

Résumé: Nanorystalline zinc oxide powders with atomic Aluminum to Zinc ratio varying between 0.1% and 20% were synthetized using a simple solgel method and annealed at different temperatures. The samples were characterized by X ray diffraction, Raman spectroscopy and SEM imaging. It is found that Aluminum doping induces a monotonous decrease in ZnO grain size for annealing temperatures of 700°C and beyond. No such effect was observed below 500°C. furthermore, peaks associated with the ZnAl2O4 spinel phase were observed at high doping concentrations on both the X ray and infrared spectral.

Mots clés: ZnO ; Al203 ; DRX ; Infra Red ; Sol-gel ; SEM ; ZnAl2O4 ; nano composite ZnO/PMMA


Study of the microstructural evolution of precipitation in AZ91 alloy

Azizi Assia ,  Hamana Djamel ,  Boumaza Leila ,  Belamr Zahira ,  Toubane Mehdia ,  Medjemedj Warda , 

Received date: 04-03-2019    Publication date: 25-04-2019    pages  44-48.