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Effect of anionic ordering on the electronic and optical properties of BaTaO2N：TB-mBJ density functional calculation

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Chinese Physics B 2017年第5期26卷 319-325页

作者： K Bettine O sahnoun M sahnoun M Driz LPQ3M University Mustapha Stambouli of Mascara Algeria university djilali liabes of sidi Bel Abbes Algeria

This report presents a first-principles investigation of the structural, electronic, and optical properties of perovskite oxynitrides BaTaO2 N by means of density functional theory（DFT） calculations using the full-potential linearized augmented plane wave（FP-LAPW） method. Three possible structures（P4mm, I4/mmm, and Pmma） are considered according to the TaO4N2 octahedral configurations. The calculated structural parameters are found to be in good agreement with the previous theoretical and experimental results. Moreover, the electronic band structure dispersion, total, and partial densities of electron states are investigated to explain the origin of bandgaps and the contribution of each orbital＇s species in the valence and the conduction bands. The calculated minimum bandgaps of the P4 mm, I4/mmm, and Pmma structures are 1.83 e V, 1.59 e V, and 1.49 e V, respectively. Furthermore, the optical properties represented by the dielectric functions calculated for BaTaO2 N show that the I4/mmm phase absorbs the light at a large window in both the visible and UV regions,whereas the other two structures（P4mm and Pmma） are more active in the UV region. Our investigations provide important information for the potential application of this material.

关键词： anionic perovskite octahedral bands dielectric augmented polar ordering struc orbital

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systems Dynamics of sheep Farms and Driving Herds of Faces to the Vagaries of Weather: Cases from the Region of El Bayadh

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Agricultural sciences 2014年第7期5卷 583-587页

作者： Mekhloufi Moulay Brahim Mahari Latifa Mekhloufi Fadila Faculty of science university El djilali liabès of sidi Bel Abbès Sidi Bel Abbes Algeria Institute of Agronomy university of Mascara Mascara Alge-ria

The cattlemen of the steppe are faced with climate risks whose consequences are at the origin of one of the essential mechanisms of the degradation of resources natural fodder, thus making uncertain the food of livestock. Thus, faces to the changing socio-economic and climatic risks, the pastoral society has implemented different adaptive strategies to ensure the reproduction of its operating systems. The objective of this study is to analyze the patterns of the use of the space of the pastoral area called El-Bayadh in order to show how the actors adopt and adapt the techniques of production available in order to ensure the security of the production of their exploitation in an environment particularly fragile, hostile and vulnerable. It is therefore to take knowledge of the basic strategies implementation and the responses provided by the livestock producers to protect themselves against the consequences of a difficult climate in order to ensure the conduct of the food needs of their animals and the reproduction of their operating system.

关键词： Breeding system Conduct of sheep Farming Climate

An Application of Nonlinear Autoregressive(NARX)Model to Predict Adsorbent Bed Temperature of solar Adsorption Refrigeration system

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Journal of systems science and systems Engineering 2023年第6期32卷 687-707页

作者： Fatih Bouzeffour Benyoucef Khelidj Unitéde Développement des Equipements solaires UDEs Centre de Développement des Energies Renouvelables CDER42415TipazaAlgeria FIMA University Djilali Bounaama of Khemis-Miliana44225Khemis-MilianaAlgeria

In any solar adsorption refrigeration system,there are three major components:a solar collector adsorbent bed,a condenser and an *** of those components operate at different temperature levels.A solar collector with a tubular adsorbent configuration is proposed and numerically *** this study,a nonlinear auto-regressive model with exogenous input is applied for the prediction of adsorbent bed temperature during the heating and desorption *** developed neuronal model uses the MATLAB Network toolbox to obtain a better configuration network,applying multilayer feed-forward,the TANsIG transfer function,and the back-propagation learning *** input parameters are ambient temperature and the uncontrolled natural factor of solar *** output network contains a variable representing the adsorbent bed *** values obtained from the network model were compared with the experimental data,and the prediction performance of the network model was examined using various performance *** mean square error(MsE)and the statistical coefficient of determination(R2)values are excellent numerical criteria for evaluating the performance of a prediction tool.A well-trained neural network model produces small MsE and higher R2 *** the current study,the adsorbent bed temperature results obtained from a neural network with a two neuron in hidden layer and the number of the tapped time-delays d=9 provided a reasonable degree of accuracy:MsE=1.0121 and R2=0.99864 and the index of agreement was *** network model,based on a high-performance algorithm,provided reliable and high-precision results concerning the predictable temperature of the adsorbent bed.

关键词： Artificial neural networks NARX solar collector adsorption refrigerator adsorbent bed temperature

soil salinity prediction in the Lower Cheliff plain(Algeria) based on remote sensing and topographic feature analysis

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Journal of Arid Land 2015年第6期7卷 794-805页

作者： Ibrahim YAHIAOUI Abdelkader DOUAOUI ZHANG Qiang Ahmed ZIANE Laboratory of Crop Production & sustainable Valorization of Natural Resources University Djilali Bounaama of Khemis Miliana Laboratory of Plant Ecology & Environment Biological Sciences Faculty University of Sciences & Technology Houari Boumediene university Center Morsli Abdellah Institute of Agricultural Environment and Resources Shanxi Academy of Agricultural Sciences

soil salinity and ground surface morphology in the Lower Cheliff plain（Algeria） can directly or indirectly impact the stability of environments. soil salinization in this area is a major pedological problem related to several natural factors, and the topography appears to be important in understanding the spatial distribution of soil salinity. In this study, we analyzed the relationship between topographic parameters and soil salinity, giving their role in understanding and estimating the spatial distribution of soil salinity in the Lower Cheliff plain. Two satellite images of Landsat 7 in winter and summer 2013 with reflectance values and the digital elevation model（DEM） were used. We derived the elevation and slope gradient values from the DEM corresponding to the sampling points in the field. We also calculated the vegetation and soil indices（i.e. NDVI（normalized difference vegetation index）, RVI（ratio vegetation index）, BI（brightness index） and CI（color index）） and soil salinity indices, and analyzed the correlations of soil salinity with topography parameters and the vegetation and soil indices. The results showed that soil salinity had no correlation with slope gradient, while it was significantly correlated with elevation when the EC（electrical conductivity） values were less than 8 d s/m. Also, a good relationship between the spectral bands and measured soil EC was found, leading us to define a new salinity index, i.e. soil adjusted salinity index（sAsI）. sAsI showed a significant correlation with elevation and measured soil EC values. Finally, we developed a multiple linear regression for soil salinity prediction based on elevation and sAsI. With the prediction power of 45%, this model is the first one developed for the study area for soil salinity prediction by the combination of remote sensing and topographic feature analysis.

关键词： Landsat ETM+ morphology sampling salinity prediction Lower Cheliff plain

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The Precipitation Concentration in the Cheliff Watershed, Algeria:A Critical Analysis for sustainable Water Resource Management

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Chinese Journal of Urban and Environmental studies 2023年第3期11卷 6-38页

作者： samiha BRAHIMI Hind MEDDI Mohamed MEDDI Faiza HALLOUZ Abdelamir sAAED HAMOUDI Department of Hydraulics Faculty of Civil Engineering and Architecture Hassiba Benbouali university of Chlef LGEE Laboratory Higher National school of Hydraulics GEE Laboratory Blida 3. djilali Bounaama university of Khemis Miliana

In this study, a statistical analysis of historical and projected values of the annual, seasonal, and supra-seasonal precipitation concentration index(PCI) was conducted for different stations in the Cheliff watershed. statistical methods such as breakpoint and trend analysis using Pettitt and Mann–Kendall tests were used for the PCI values of annual, monthly, and supra-seasonal precipitation data between 1950 and 2014. The PCI values varied between 14.24% and 24.86% annually, between10.75% and 18.74% seasonally, and between 11.23% and 26.98% supra-seasonally. According to the Pettitt and Mann–Kendall tests, there was an insignificant change in precipitation distribution during the study period. spatial analysis using the inverse distance weighting(IDW) method confirmed the minor variability in precipitation distribution in the study area. The Pearson correlation coefficient between oscillation indices and PCI values at different scales showed significant values with the Mediterranean Oscillation index(MOi), North Atlantic Oscillation(NAO), and Western Mediterranean Oscillation index(We MOi), highlighting their potential influence on annual PCI values. For the climate projection scenarios, projected PCI values align with historical PCI values. Application of Pettitt and Mann-Kendall tests to the projected PCI series shows that there will not be a significant change in future precipitation distribution.

关键词： PCI Cheliff trend analysis breakpoint IDW climate projection scenarios.

Nutritional status of Elderly People Living at Home in sidi-Bel-Abbes (West Algeria)

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Food and Nutrition sciences 2013年第8期4卷 860-865页

作者： N. Menadi M. B. Khaled B. Merrakchi s. Belbraouet Department of Biology Faculty of Sciences Djilali Liabes University of Sidi-Bel-Abbès Sidi-Bel-Abbès Algeria Department of General Medicine Sidi-Lahcen Health Center Sidi-bel-Abbès Algeria university of Moncton Ecole des Sciences des Aliments de Nutrition et des Etudes Familiales Moncton Canada

The aim of the study was to assess the nutritional status of a cohort of elderly people living independently at home. 314 elderly individuals were selected during general medicine examinations. The collection of nutritional data concerned the measurement of some anthropometric parameters (body weight, height, and BMI), the Mini Nutritional Assessment (MNA) and serum albumin. The average age was 72.92 ± 6.26 years with a feminine predominance (59.55%). The BMI was 25.63 ± 4.43 Kg·m-2 and serum albumin 36.45 ± 5.77 g·L-1. 61% of the investigated population were affected by chronic diseases such as: diabetes (39%). Using the MNA as a mean of screening;46.18% of individuals presented a risk of malnutrition and 4.78% were undernourished. However, when the BMI and serum albumin were used;14.01% and 42.35% have been considered as undernourished respectively. The MNA seems to be a more sensitive tool rather than the other screening parameters (BMI and serum albumin) in the assessment of nutritional risk in the elderly.

关键词： Elderly Nutritional status Anthropometric Parameters Mini Nutritional Assessment Albumin

Geochemical characterization of the salinity of irrigated soils in arid regions(Biskra, sE Algeria)

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Acta Geochimica 2021年第2期40卷 234-250页

作者： Mohamed Amine Abdennour Abdelkader Douaoui Jesus Barrena Manuel Pulido Abdelhamid Bradai Amel Bennacer Chiara Piccini Alberto Alfonso-Torreno Laboratory of Ecosystem Diversity and Agricultural Production system Dynamics in Arid Zones(DEDsPAZA) Mohamed Khider University07000 BiskraAlgeria Laboratory of Crop Production and sustainable Valorization of Natural Resources Djilali Bounaama University44225 Khemis MilianaAlgeria GeoEnvironmental Research Group University of Extremadura10071 CaceresSpain Laboratory of Water and Environment Hassiba Ben Bouali University02180 ChiefAlgeria Laboratory of Valorization and Conservation of Biological Resources Faculty of SciencesMohamed Bougara University35000 BoumerdesAlgeria Research Centre for Agriculture and Environment Council for Agricultural Research and EconomicsVia della Navicella 2-400184 RomeItaly

The agriculture in Biskra,southeastern Algeria,is based on traditional practices and characterized by small irrigated *** the last decades,the increasing demand in water as well as the scarcity of rainfall has forced many farmers to use groundwater of low quality to maintain the profitability of their ***,this practice seems to be the main harmful factor for soil quality in the region since it is responsible for the salinization of the irrigated *** to assess the impact of this phenomenon,the soils of the irrigated perimeter of El Ghrous-a representative rural community located in the west of Biskra-have been analyzed.A set of 82 soil samples was collected from top and subsoil(0-15 and15-35 cm respectively),on which the following physicochemical analyzes were performed:Ca^(2+),Mg^(2+),K^(+),Na^(+),Cl^(-),sO_(4)^(2-),HCO_(3)^(-),NO_(3)^(-),pH,electrical conductivity(EC)and sodium adsorption ratio.A Principal Component Analysis was performed to individuate the geochemical processes that influenced significantly the evolution of soil salinity and its *** results showed a calcium sulfate(CasO_(4))facies with a high risk of salinity and a low to medium risk of *** calcite residual alkalinity and generalized residual alkalinity decreased as the solutions became more *** of the samples were oversaturated in carbonate minerals(aragonite,calcite,and dolomite)and under saturated in evaporitic minerals(anhydrite,gypsum,and halite).Finally,two multiple linear regressions(using cations and anions as independent variables)have been proposed to quantify soil *** equations,with an accuracy of 85%,can represent a time and money-saving tool for managers and farmers to estimate the EC,in comparison to the traditional estimation methods.

关键词： Electrical conductivity Cations Anions soil quality saturation index PHREEQC

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Theoretical study on the Origins of the Gap Bowing in MgxZn1–xO Alloys

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Modeling and Numerical simulation of Material science 2012年第3期2卷 60-66页

作者： F. Z. Aoumeur-Benkabou M. Ameri A. Kadoun K. Benkabou Laboratoire de Microscopie Microanalyse et Spectroscopie Moleculaire Faculté des Sciences. Département de Physique Sidi-bel-abbes Algeria Djilali-Liabes University of Sidi-Bel-Abbes Algeria

The full potential linear muffin-tin orbital (FP-LMTO) method was applied to study the structural and electronic properties of the compounds MgO, ZnO and their alloy MgxZn1–xO in the zincblende and NaCl structures. Results are obtained using the local density approximation (LDA), the ground-state properties like lattice constant and bulk modulus obtained agree very well with experimental and other theoretical calculations. The effect of composition on lattice constant from Vegard’s law and the bulk modulus was investigated. The microscopic origins of the gap bowing were explained by using the approach of Zunger and co-workers. It is concluded that the energy band gap bowing is primarily due to chemical charge-transfer effect. Contribution of volume deformation and structural relaxation to the gap bowing parameter is found to be very small.

关键词： FP-LMTO Method structural and Electronic Properties MgxZn1–xO Alloy Bowing

In Vitro Effects of Oil’s Fatty Acids on T-Cell Function of Obese Men

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Food and Nutrition sciences 2017年第2期8卷 277-293页

作者： Asmaa Meraou Hafida Merzouk Amel saidi Amel Medjdoub sid Ahmed Merzouk Mohamed Bénali slimane Belbraouet Laboratory of Physiology Physiopathology and Biochemistry of Nutrition Department of Biology Faculty of Natural and Life Sciences Earth and Universe University of Abou-Bekr Belka&#239 d Tlemcen Algeria Laboratory of Biotoxicology Djilali Liabes University Sidi Bel Abbès Algeria Department of Technical sciences Faculty of Engineering University of Abou-Bekr Belka&#239 d Tlemcen Algeria école de Nutrition Université de Moncton New Brunswick Canada

Background: Dietary fatty acids have important homeostatic functions in regulating the immune response and may exert beneficial effects on immune alterations during obesity. Objective: To assess the in vitro effects of oil fatty acids, different oils (olive, linseed, Nigel, sunflower) were tested on T-lymphocyte proliferation, Th1- and Th2-type cytokine production, and intracellular oxidant/antioxidant status in obese patients. Methods: Peripheral blood lymphocytes were isolated using Histopaque and were in vitro cultured and stimulated by Con A in the presence or absence of the oils. Cell proliferation, interleukin-2, interleukin-4 and interferon-γ (INFγ) secretions and intracellular oxidative status (glutathione (GsH), malondialdehyde (MDA), carbonyl protein levels, catalase activity and micronuclei frequency) were investigated. Results: Abnormalities in lymphocyte function and intracellular oxidative stress were observed in obesity. Linseed oil induced a reduction in T-lymphocyte proliferation and IL-2 production while Nigel oil increased them in both obese and control groups. In addition, Nigel oil enhanced IFNγ and IL-4 secretion. Olive and sunflower oils had no effect on lymphocyte proliferation and cytokine secretion in both groups. Linseed and Nigel oils induced an increase in T cell GsH concentrations and catalase activity with a concomitant decrease in MDA, carbonyl protein contents and micronuclei frequency especially in obese patients. Conclusion: Linseed and Nigel oils had beneficial effects on lymphocyte proliferation, cytokines secretions and redox status, while olive and sunflower oils had no effects on immune cell function in obesity.

关键词： Obesity Lymphocytes Olive Oil Linseed Oil Nigel Oil sunflower Oil Cytokines Oxidant/Antioxidant status