Activité antioxydante des composés phénoliques d’huile d’olive extraite par méthode traditionnelle

L'objectif de cette etude est de determiner la teneur en composes phenoliques totaux de lfhuile dfolive de la variete Chemlal obtenue par extraction artisanale et dfen tester leur pouvoir antioxydant. La teneur phenolique a ete determinee par la methode universelle Folin-Ciocalteu, alors que lfactivite antioxydante a ete evaluee par deux methodes complementaires: le test du radical libre 2,2-diphenyl-1-picrylhydrazyl et le test du β-carotene/acide linoleique. Cette huile dfolive a montre une teneur en composes phenoliques totaux de 167,29 ± 2,71mg EAG/kg et une valeur dfIC50 egale a 25, 38 ± 0,64mg/kg par le test DPPH et une activite antioxydante relative par le test β-carotene/acide linoleique de lfordre de 67,40 ± 1,02%. Le controle positif hydroxy toluene butyle (BHT) a devoile respectivement 23,86 ± 0,14mg/kg et 95,88 ± 0,85%. Ces resultats revelent une possible utilisation de cette huile dans la lutte contre les maladies lies au stress oxydant.Mot cles : Oleaeuropea, β-carotene/acide linoleique, DPPH, variete Chemlal, regime mediterraneen

New Actuator Disk Model for the Analysis of Wind Turbines Wake Interaction with the Ground

Wake models based on Actuator Disk theory are usually applied to optimize the wind farm layouts and improve their overall efficiency and expected AEP. Despite the effectiveness of the existing models, most Actuator Disk approaches are based on the flow axisymmetric assumption, without considering the ground effect on the wake behavior. However, it has been shown that the mast’s height, or distance from the wind turbine to the ground, has an influence on the wake expansion on both hub’s side and at downstream of the wind turbine. Therefore, in this study, a hybrid CFD-BEM-Actuator Disk approach is developed to address the lack of the existing models. In the proposed model, the 3D wind rotor is modeled by a set of blade elements. Then, the local lift and drag forces acting on each blade element are calculated using BEM theory and incorporated into the momentum equation. This BEM-AD model is implemented in a User Defined Function (UDF) that is loaded into the CFD software. Thereby, ground effects are considered to be a wall boundary and defining a wind boundary layer profile at the inlet boundary, which describes the Atmospheric Boundary Layer (ABL). For the validation of this new Actuator Disk model, an enhanced experimental study is conducted at the Dynfluid Laboratory wind tunnel (ENSAM School Paris Tech). The Particle Image Velocimetry (PIV) measurements are used for the experimental wake explorations applied to a miniature two-bladed wind turbine. The wake developments are analyzed at two different hub heights ratio, h/D = 0.7 and 1.0 (where h is the hub height, and D is the wind rotor diameter). The analysis of the outcomes showed that the numerical simulations are in good correlation with the experimental measurements of the ENSAM wind tunnel. The numerical results show that for h/D=0.7, the upper half of the rotor operates within the boundary layer whereas the lower tip vortices are mainly developed in the horizontal direction with lower intensity compared to the upper tip vortices. This effect was not observed for the case h/D=1.0 where the rotor operates outside of the boundary layer; however, the wake centerline is upward deflected at about 0.3D. The main conclusion is that a distance above 7D must be observed between wind turbines to optimize the wind farm performance and over 1D hub height be required to limit the influence of the ground boundary layer effect

The use of the modular dynamic tool in petrophysical parameters evaluation : application to the Bir-Berkine reservoirs - Algeria

The technological development and the complexity of the reservoirs unceasingly encourage us to improve our working methods, of acquisition processing and interpretation of well logs, but the information provided by the well logs related to the localisation of hydrocarbons bearing zones is not perfect. The Modular Dynamic formation Tester (MDT) is a new generation of tools designed for the more pointed tests of formation. By using its various configurations and options it offers, unquestionable opportunity to obtain, starting from the pressure taps, a varied range of invaluable information for the management of the reservoirs. The virgin reservoirs service MDT is used:To determine the levels of the contacts of fluids (WOC and GOC): to determine the densities of the fluids; to characterize the reservoir heterogeneity; to decide the completion mode; to optimize the mud density to be used. In the development of reserves: to establish a pressure profile; to estimate the vertical and horizontal permeabilities; to detect the robbers zones; to determine the communications between the wells; The principal goal of this work is by combining the results of petrophysic measurements and pressure. To achieve this goal the study is articulated on four essential points:• The evaluation of the petrophysical parameters of the Bir-Berkine reservoirs; • Interpretation of pressure measurements; • Well to well correlation; • Result synthesi

Microfaciès et modèle sédimentaire du Carbonifère (Serpukhovien-Moscovien inférieur) du bassin de Reggane (Sahara Central, Algérie)

4 figs, 12pl.phinfo:eu-repo/semantics/publishe

A sedimentological approach to refining reservoir architecture using the well log data and core analysis in the saharan platform of algeria

Improved reservoir characterisation in the mature oil applied to Gourara Field of Sahara in Algeria, aimed at maximising both in-field and near-field hydrocarbon potential, requires a clearer understanding of sub-seismic stratigraphy and facies distributions. In this context, we present a regional, high-resolution sequence stratigraphic framework for the Oued Namouss Field based on extensive sedimentological re-interpretation of core and wireline log data, combined with core analysis and published literature. This framework is used to place individual reservoirs in an appropriate regional context, thus resulting in the identification of subtle sedimentological and tectono-stratigraphic features of reservoir architecture that have been previously overlooked. We emphasise the following insights gained from our regional, high-resolution sequence stratigraphic synthesis: (1) improved definition of temporal and spatial trends in deposition both within and between individual reservoirs, (2) development of regionally consistent, predictive sedimentological models for two enigmatic reservoir intervals (the Formations I and II), and (3) recognition of subtle local tectono-stratigraphic controls on reservoir architecture, and their links to the regional structural evolution of the Province. We discuss the potential applications of these insights to the identification of additional exploration potential and to improved ultimate recovery.In this research a procedure was developed to assess and quantify uncertainties in hydrocarbon estimates related to depositional facies, petrophysical data and gross reservoir volumes. This procedure was applied to the Gourara Field, which is a mature gas field in the Oued Namous Basin, Algeria. The aim was to investigate the reasons for an unexpectedly high hydrocarbon recovery facto

Microfaciès et modèle sédimentaire du Carbonifère (Serpukhovien-Moscovien inférieur) du bassin de Béchar (Sahara Septentrional, Algérie)

3 figs, 15 pl.phinfo:eu-repo/semantics/publishe

Petrophysical analysis in reservoir characterization : application in the triassic hamra gas field, Algeria

Petrophysical evaluation of the Upper and Lower shaly gas sand reservoirs of the Sahara field, using conventional well log interpretation techniques and relating the results to core data, shows that the Upper reservoir is of very good quality and apparently better than the Lower reservoir. Evaluation of the petrophysical parameters from the wells in the field show porosities ranging from 12 to 20% and permeabilities of about 500 mD, which are similar to regional values of 12 to 20% porosity and 1000 mD permeability. A crossplot-based lithological study shows that the matrix is dominantly quartz, with calcitic and dolomitic cements, a high percentage of montmorillonite clays, and a smaller percentage of illite and micas. A study of lateral variations of petrophysical parameters shows that porosities increase from NE to SW, similar to the saturations. This study shows the role of wireline petrophysical analysis as a tool in reservoir characterization of shaly sands in the Sahara field. This paper examines the use of log analysis and mean petrophysical reservoir parameters as a tool in successfully establishing reservoir architecture and fluid-flow trends. Data from Gamma Ray, Neutron, Density, Sonic and Resistivity logs was utilized for petrophysical analysis to correlate layers in this reservoir characterization study. Petrophysical evaluation of the Shaly Sand gas reservoir (TAGS) of the Rhourde Hamra field, using conventional well log interpretation techniques and relating the results to core data, shows that the reservoir is of very good qualit

Facies analysis of triassic formations of the Hassi R’Mel in southern algeria using well logs : recognition of paleosols using log analysis

Well logs are essential in the study of geological formations, in terms of taking into account the nature and the structure of the formations, as well as the sedimentary processes. Qualitative and quantitative interpretations of well logs respond to a sedimentologic need as well as the establishment of lithological columns, according to the response to logging tools. In this study, electrofacies have been defined by manual well-log analysis of ten surveys of Triassic formations in the Hassi R'Mel area of Algeria. The data thus obtained were then matched with sedimentary facies defined by core analysis. The results obtained during the facies analysis made it possible to define ten electrofacies (sands, shale, dolomite, and evaporite, as well as the presence of andesite and clay). The model obtained by the Petrolog software was also developed and tested on other wells. A semi-automatic data processing was then carried out on seven other wells.Our aim is to highlight the added value of this integrated regional-scale to reservoir-scale approach in identifying nearfield exploration potential and additional recovery opportunities in producing reservoirs. Based on this aim, we emphasise the following points using our facies modelling: (1) improved definition of deposition within and between reservoirs, (2) development of regionally sedimentological models for reservoir intervals (the Hassi R’Mel Formations), and (3) recognition of paleosols from well log analysis and controls on reservoir architecture and their links to the Triassic Province of Algeri

Electrostatic template-assisted deposition of microparticles on electrospun nanofibers: towards microstructured functional biochips for screening applications

Electrostatic Template-Assisted Deposition (ETAD) of microparticles is described as a new process to control the deposition of microparticles by electrospraying onto a substrate. It relies on the construction of an electrostatic template by electrospinning a thin layer of fibers onto a micropatterned collector. Because the fibers cannot release their charges when they are suspended over cavities of the micropatterned collector, an electrostatic template is formed with repulsive and attractive domains. This electrostatic template is then used to guide precisely the particle deposition during the electrospraying step. Microstructured bi-layer composites with a great variety of micropatterns can thus be elaborated with any kind of materials allowing the use of the ETAD process for a wide range of applications. As a proof of concept, the ETAD process was applied for the production of composite scaffolds with poly(ε-caprolactone) nanofibers covered by a micropatterned layer of hydroxyapatite. This scaffold was then embedded in a biochip containing 21 wells and used for MG-63 cell proliferation and mineralization studies, showing their possible application in the screening of the scaffold structure for tissue engineering