JFAS_Vol 06 N 01
Permanent URI for this collectionhttps://dspace.univ-eloued.dz/handle/123456789/7201
Browse
Recent Submissions
Item Electric Field Measurement In Rod-discontinued Plane Air Gaps Using Distributed Capacity Probe(University of Eloued جامعة الوادي, 2014-01-01) Khechekhouche, A.; Benattous, D.; Mekhaldi, A.; Boubakeur, A.The present experimental carried out investigations aimed at elucidating the effect of earth discontinuity on the breakdown voltage of short rod-plane air gap (80 to 160 mm) under negative lightning impulses (-1.2/50s). We also carried out investigations on electric field measurement on the surface of a discontinuous plane of a rod-plane air gap arrangement. For this purpose, we used a probe with distributed capacity, under negative lightning applied impulse voltage. The probe is incorporated on the same level of plane surface. The interface locally reinforces the electric field. The electric field increases at the interface may lead to a discharge between the high voltage rode and the interface. In the vicinity of the interface, we observe a kind of discontinuity in the evolution of the electric field intensity. This one becomes greater than the value obtained in the case of gaps with homogeneous plane earth.Item Compared Performances Of The Experimental Digesters Of The Animal Biomass(University of Eloued جامعة الوادي, 2014-01-01) M’sadak, Y.; Ben M’barek, A.This study proposes to look further into experimentally of the effect of the variation of certain physicochemical parameters of anaerobic digestion on the quantitative gas productivity of four digesters of treating bovine dejections. Moreover, four digesters supplied with the avicolous droppings, in different concentrations of Dry Matter (DM), were followed. The assessments of depollution (Suspended Matter and Biological Demand for Oxygen) together with qualitative energy (gas composition and calorific value) were also appreciated. We can release particularly that: the quantity of bovine biogas produced is variable according to the parameters of digestion. It is maximum in the presence of high temperature and under mechanical agitation of the substrate introduced; the quantitative productivity is more interesting in the case of the digesters avicolous. It is more important with the increase of the concentration of solids; the digester with 8% DM presents attractive valuations of depollution and energy efficiency.Item Practical Common Weight Maximin Approach For Technology Selection(University of Eloued جامعة الوادي, 2014-01-01) Alinezhad, A.; Amini, M.A practical common weight Maximin approach with an improved discriminating power for technology selection is introduced. The proposed Maximin approach enables the evaluation of the relative efficiency of decision-making units (DMUs) with respect to multiple outputs and a single exact input with common weights. Its robustness and discriminating power are illustrated via a previously reported robot evaluation problem by comparing the ranking obtained by the proposed Maximin approach framework with that obtained by the DEA classic model (CCR model) and Minimax method (Karsak & Ahiska,2005). Because the number of efficient DMUs is reduced so discriminating power of our approach is higher than previous approaches and because Spearman’s rank correlation between the ranks obtained from our approach and Minimax approach is high therefore robustness of new approach is justified.Item Comparative Study Of Honey Collected From Different Flora Of Algeria(University of Eloued جامعة الوادي, 2014-01-01) Rebiai, A.; Lanez, T.The aim of the present study was to evaluate the physical and chemical properties of five Algerian unifloral types of honey. Several physical parameters of honey, such as pH, moisture content, electrical conductivity, total dissolved solids, color intensity and total sugar content, were measured. The mean pH, moisture content, EC and water insoluble solids of Algerian honey were 4.41± 0.58, 15.3 ± 1.5%, 0.324± 0.116 mS/cm and 0.141± 0.065%, respectively. The mean color was 81 ± 72 mm Pfund. The majority of honey samples test results (moisture content, electric conductivity and acidity) levels were within the acceptable range of world honey standards.Item Contribution To The Development Of A Method Of Estimate Of The Time Of Concentration Of The Maximum Flows Of The Rain Risings(University of Eloued جامعة الوادي, 2014-01-01) Ladjel, M.Among the characteristics that determine the maximum throughput flood genesis, concentration time has an important place. The maximum phase shift of a flood rain is subjected to different types of river regulation. This is caused by the friction forces in the river bed, by the gradual change of the wetted area by the slope and also by the flow exchanges. The flood speed is proportional to the water level in the river bed or the corresponding flow.Item Maximum Runoff Of The Flood On Wadis Of Northern Part Of Algeria(University of Eloued جامعة الوادي, 2014-01-01) Ladjel, M.; Gopchenko, E. D.; Ovcharuk, V. A.Wadis of Algeria are characterized by a very irregular hydrological regime. The question of estimating the maximum flow of wadis is relevant. We propose in this paper a method based on an interpretation of the transformation of surface runoff in streamflow. The technique of account the maximal runoff of flood for the rivers of northern part of Algeria based on the theory of channel isochrones is offered.The realization of this method is performed on the basis of hydrometeorological data standarts.Item Phytochemical Study And Evaluation Of The Antimicrobial And Antioxidant Activity Of Essential Oils And Phenolic Compounds Of Pistacia Lentiscus L(University of Eloued جامعة الوادي, 2014-01-01) Arab, K.; Bouchenak, O.; Yahiaoui, K.This work aims for the phytochemical study and evaluation of the antioxidant activity of phenolic compounds and essential oils of medicinal plant Pistacia lentiscus L. quantitatively and qualitatively. Through the results obtained, it appears that the leaves and fruits are rich in substances with a high antioxidant power. The yield of the phenolic compounds obtained from 10g to powder of plant is for leaves 116.49 % and 61.34 % for fruit . For essential oils, it is 0.253 ± 0.131 % for 100 g of plant material. The chromatographic profile of the essential oil of Pistacia lentiscus L. shows that monoterpenes are the major compound (9.675 % of identified molecules). The strong antioxidant activity of extracts obtained only confirms the traditional use of this plant by the local population.Item Effect Of Copper On Passivity And Corrosionbehavior Of Fe-xc-5cu Alloy(University of Eloued جامعة الوادي, 2014-01-01) Ferhat, M.; Benchettara, A.; Amara, S. E.The correlation between corrosion behavior rate of annealed Fe-xC-5Cu alloys and their microstructure and phase composition is presented. The metallurgical analyses, including, X-Ray diffraction (XRD), the scanning electron microscopy (SEM) with energy dispersive analysis (EDX), and induction hardening characterization are conducted to study the Fe-C-Cu alloys.Corrosion parameters in H2SO4 1N solution have been established by carrying out electrochemical studies such as potentiodynamic (Tafel polarization and linear polarization, LP) and electrochemical impedance spectroscopy (EIS).The coupled effect copper/microstructure is discussed. Alloying Cu showed a beneficial effecton hypoeutectoid steel and harmful effect on hypereutectoid steel. The improved corrosion resistance is related to cementite morphology and by a copper dissolution/re-deposition process.Item Thermodynamic Parameters Of Solutions Of Sildenafil Citrate In Some Organic Solvents At Different Temperatures(University of Eloued جامعة الوادي, 2014-01-01) Baluja, S.; Bhesaniya, K.The solubility of Sildenafilcitrate in someorganic solvents; hexane, toluene,1-butanol and 1,2 dichloroethanehas been determined using gravimetric method over different temperature range (298.15 K to 328.15 K) at one atmospheric pressure. The modified Apelblat and Buchowski-Ksiazczak λh equations were used to correlate the experimental solubility data.Further, various thermodynamic parameters have been evaluated from these solubility data.Item Numerical Simulation Andmodelingofunsteady Flowaround Anairfoil. (aerodynamic Form)(University of Eloued جامعة الوادي, 2014-01-01) Habib, M. Y.; Djaaffar, R.Duringthis work, we simulatedanunsteady flowaround anairfoiltypeNACA0012using theFluent software. The objectiveis to controlthe codeon the one handandon the other handthe simulationofunsteady flows. By simulatinganunsteady flowReynolds number(Re =6.85*106) andMach number(M =0.3), we havethe flowingwitha grid(mesh) adequatenumerical resultsandexperimental dataare ingood agreement. To representthe results ofthe simulationwe havevalidated bycomparing the valuesof aerodynamic coefficientswith those ofexperimental data.