JFAS_Vol 08 N 01
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Item Modeling The Potential Impacts Of Global Climate Change In Bangladesh: An Optimal Control Approach(University of Eloued جامعة الوادي, 2016-01-01) Biswas, H. A.; Rahman, T.; Haque, N.One of the hottest issues in the recent environmental research worldwide has become the harmful effects of climate change on the ecosystems and environment due to global warming. Bangladesh is one of the most vulnerable countries not only in the South East Asia but also in the world. It is predicted that a large portion of the South-western region of Bangladesh will go under sea in the next 50 to 100 years due to sea level rise. In this paper, we first discuss some potential impacts of climate change in Bangladesh and its aftermath on the ecosystems and secondly, we study a mathematical model of climate change in terms of ordinary differential equations (ODEs) and apply optimal control techniques in the form of Pontryagin Maximum Principle (PMP) to investigate the control strategy of greenhouse gases (GHGs). We study the model numerically using some known nonlinear ‘optimal control solvers’ and the results are illustrated with numerical simulations.Item A Field Study Of Indicators Of The Performance Of Four Absorption Chillers In The Sudano-sahelian Region Of Cameroon(University of Eloued جامعة الوادي, 2016-01-01) Chedop, A.n.n.; Djongyang, N.; Tchinda, R.; Zaatri, A.; Kana, J.d.This paper presents a field study of indicators of the performance of absorption refrigerating systems in the Sudano-Sahelian region of Cameroon. A modeling of various components of the system is performed in order to choose the technology best adapted for the region. Based on the characteristics from the manufacturers, four absorption chillers were studied; namely: EAW Schüco LB 15 and 30; Rotartica Solar 045 and Sonnenklima Suninverse. The model of Kühn and Ziegler and meteorological data of the city of Maroua ((14.33 °E, 10.58 °N) were used to assess the coefficient of the performance (COP) of these machines. Results showed that the Sonnenklima Suninverse technology is best suited for the climatic conditions of the Sudano-Sahelian region with COP values between 1.5 and 3.5.Item Study And Numerical Simulation Of Solar System For Air Heating(University of Eloued جامعة الوادي, 2016-01-01) Ghodbane, M.; Boumeddane, B.; Moummi, N.; Largot, S.; Berkane, H.The use of solar energy in sunny countries, is an effective outil for compensate the lack in the energy, their benefits are not related only to its economic benefits but especially for the environmental protection, so we must find solutions to the problems of pollution. This work is a theoretical study of a solar flat plate collector; air is used as the heat transfer fluid. In this study, we established in first step calculation of solar radiation in various sites in Algeria (Adrar, El Oued, Bechar, Biskra and Tamanrasset). The second step is the parameters influence study of the sites and climate on the performance of our collector. The results obtained are encouraging for the use of this type in the heating in the winter; also it can be used in different kinds of drying.Item Description And Variation Factors Of Individual Cell Counts Of Milk In Of Units Bovins Aboveground (tunisian Sahel)(University of Eloued جامعة الوادي, 2016-01-01) M’sadak, Y.; Haj Mbarek, R.; Mighri, L.This study has as essential objective the diagnosis of breast health of a sample of 120 cattle farms conducted in above ground in the Tunisian Sahel, from the Individuals Cellular Counts (ICC). The analysis of the ICC has inferred that the infection status of the breasts is worrying (50% of the sample is infected). Depending on governorates, Sousse always haves the highest ICC, followed by Monastir with lower ICC and finally Mahdia with the lowest ICC. The determination and distribution of arithmetic averages (AA), geometric averages (GA), the quartiles and interquartile of ICC, led to highlight that AA of ICC are always higher than the GA of ICC. The median is closer to GA of ICC than AA of ICC, confirming the utility of the use of the GA in the cell distribution. The rank and stage of lactation, season of calving and milk production have importance on the evolution of the ICC.Item Desorption Of Te Capping Layer From Znte (100): Auger Spectroscopy, Low-energy Electron Diffraction And Scanning Tunneling Microscopy(University of Eloued جامعة الوادي, 2016-01-01) Sossoe, K. K.; Dzagli, M. M.; Sylla, A.; Grandidier, B.; Mohou, M. A.; Zoueu, T. J.; Toure, S.The influence of the annealing temperature to desorb a protective Te capping layer of the zinc telluride (ZnTe (100)) surface was investigated. The surface reconstruction of the ZnTe (100) upon the removal of a Te capping layer grown by the molecular beam epitaxy was characterized by different methods. Auger spectroscopy brought out the chemical composition of the surface before and after annealing; the Low-energy electron diffraction (LEED) gave information about the crystallographic structure. The surface crystallographic configurations of tellurium Te (c (2x2)) and Te (c (2x1)) are confirmed by scanning tunneling microscopy (STM). Such a study reveals a phase transition from a rich-Te to a poor-Te surface as the annealing temperature increasesItem Lamination Method Of Flood Wadis And Projection Of The Laminated Flood Hydrograph(University of Eloued جامعة الوادي, 2016-01-01) Ladjel, M.The catastrophic floods in semi-arid areas are often caused by floods storm that occur at any time during the year, including the hot season. The prevention of these floods could be done by the construction of small dam hills. This requires the control of theoretical concepts hydrological sizing, especially the hydrological structure to evacuate floods. We suggest a method to calculate the optimal regulation flow of the flood and also the development of a direct calculation formula of a laminated maximum flow. The analysis of the hydro graph’s analogy at the input and the output of the dam, allow searching the dependencies between their characteristics. Knowing the characteristics of the hydrograph flood of the project and the reserved capacity for the amortization of the flood, we can directly determine the laminated maximum flow and project the hydrograph of the laminated flood.Item Copper-(s)-n-methylpyrrolidine-2-carboxylate Catalyzed N-arylation Of N5h-1,2,5-thiadiazolidine 1,1-dioxides(University of Eloued جامعة الوادي, 2016-01-01) Dehamchia, M.; Regaïnia, Z.A copper-catalyzed N-arylation of N5H-1,2,5-thiadiazolidine 1,1-dioxides derivatives (cyclic sulfamides) is described. Reactions were carried out using Ullmann–Goldberg-type condensation with (S)-N-methyl-2-carboxylate as the ligand, and N-arylated products were obtained with moderate to good yields. The structures of the synthesized compounds were confirmed based on analytical and spectral data.Item Trace Elements Lateral Distribution And Limitations For Revegetation In Lead Mine Soils: Case Of Lakhouat Mine, Tunisia(University of Eloued جامعة الوادي, 2016-01-01) Sahraoui, H.; Attia, R.; Hamrouni, H.; Hachicha, M.Anthropogenic activities such as mining have increased the prevalence and occurrence of trace elements soil contamination. Abandoned mine tailings cause the contamination of adjacent agricultural soils. In Lakhouat mining area (West-Northern Tunisia), the dispersion of particles containing Pb, Zn and Cd results in the contamination of the surrounding agricultural soils. These soils presented high concentrations of Pb (1272 mg kg-1), Zn (5543 mg kg-1) and Cd (25 mg kg-1). Furthermore, the tailing sample and soil sample close the dam tailing presented higher concentrations of Pb, Zn and Cd and conferred more limitation factors for revegetation than adjacent soils of mining area. The main limiting factors of mine soils are their low effective depth, low organic matter content and low phosphorus content and an imbalance between potassium and manganese exchangeable cations. These mine soils are strongly affected by high Pb, Zn and Cd levels which hinder revegetation.Item An Exploration On The Synthesis And Bio-applications Of Derivatives Of Heterocyclic Mannich Bases(University of Eloued جامعة الوادي, 2016-01-01) Manjula, P.s.; Sarojini, B. K.; Narayana, B.; Darshan Raj, C. G.The Mannich reaction is a three-component reaction of an aldehyde, a primary or secondary amine and a ketone which is one of the most powerful C-C bond forming reactions in organic synthesis. It leads to β-amino carbonyl compounds, which are useful for the syntheses of nitrogen containing compounds, such as natural products and medicinally relevant compounds. The versatility and potential of these compounds to introduce both functional and structural diversity using the Mannich reaction have stimulated the creativity of chemists. Keeping in view of the importance of this organic moiety in the field of medicine and biology here an attempt has been made to review the synthesis and biological importance of heterocyclic Mannich base derivatives.Item Determination Of Binding Parameters Of 2-(ferrocenylmethyl-amino)benzonitrile And 3-(ferrocenylmethylamino)benzo-nitrile With 1,1-diphenyl-2-picrylhydrazyl Free Radical(University of Eloued جامعة الوادي, 2016-01-01) Lanez, T.; Henni, M.Spectrophotometric techniques based assay were developed for the determination of binding parameters like binding constant and binding free energy of two potential antioxidants ferrocene derivatives: 2-(ferrocenylmethylamino)benzonitrile (2FMAB), 3-(ferrocenylmethyl-amino)benzonitrile (3FMAB), and a standard ascorbic acid (AA) with 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH). Obtained resultants indicated that the adduct 3FMBA-DPPH shows highest binding constant and highest binding free energy (2.28×105 M-1) and (-30.59 KJmol-1) respectively. Binding free energy of 3FMAB-DPPH is almost three times greater than that of the adduct 2FMAB-DPPH (-10.47 KJmol-1) and also is greater than the adduct formed between the standard antioxidant ascorbic acid and 1,1-diphenyl-2-picrylhydrazyl radicals (AA-DPPH) (-19.29 KJmol-1).