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Chinese Journal of Chemical Engineering 2017年第9期25卷 1282-1287页

作者： sana dardouri Jalila sghaier unité de thermique et thermodynamique des procédés industriels Ecole Nationale d'Ingénieurs de Monastir

Removal of dye from the industrial wastewater is one of the most important subjects in water pollution *** adsorption/desorption cycles of a basic dye, methylene blue, on the internal almond shell, sheep manure waste and sawdust were investigated using fixed bed column experiments in order to study the adsorption capacity to remove MB and adsorbent regeneration efficiency. The adsorption breakthrough curves were predicted by the Thomas model, Yoon Nelson model, and Wolborska model and modified dose–response model using non-linear regression analysis. The results showed that the modified dose–response model was more suitable for the description of breakthrough curves for three adsorbents only in the first cycle. Although sheep manure waste presents the highest adsorption capacity, it is hard to regenerate and needs more time regeneration. Conversely, the internal almond shell presents lower adsorption capacity, but they are more readily regenerated.

关键词： Fixed bed adsorption Breakthrough curves modeling Adsorbents selection Methylene blue Regeneration

Effects of nano-voids and nano-cracks on the elastic properties of a host medium: xfem modeling with level-set function and free surface energy

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Acta Mechanica sinica 2019年第4期35卷 799-811页

作者： B.E. Hachi d. Hachi M. Haboussi Laboratoire de développement en Mécanique et Matériaux (LdMM) Université de Djelfa PB 3117 Djelfa Algérie Laboratoire d’Automatique Appliquée et diagnostics industriels (LAAdI) Université de Djelfa PB 3117 Djelfa Algérie Laboratoire des sciences des procédés et des Matériaux (LsPM) Université Paris 13 UPR 3407 CNRS Paris France

This work deals with the influences of nano-heterogeneities in the form of voids/cavities or cracks on the elastic (please confirm which word is correct. effective or elastic? According to the title of paper, I choose elastic.) properties of a host medium. With a relatively large ratio of apparent-surface to volume and particularly strong physical interactions with the surrounding medium at nano-scale, nano-heterogeneities can potentially affect the elastic(effective or elastic?) properties of the parent medium (matrix) containing them in a significant manner. This has been reported by various theoretical and experimental studies, some of them are discussed in the present paper. To describe the positive (reinforcement) or negative (degradation) effect of the nano-heterogeneities from the modeling perspective, it is necessary to take into account the energy of interfaces/surfaces between nano-heterogeneities and the matrix which, by the fact of the relatively large extent of their apparent surface and their strong physical interaction with their neighborhood, can no longer be neglected compared to those of the volume energy. Thus, to account for the effects of interfaces/surfaces in a nanostructured heterogeneous medium, the coherent interface model is considered in the present investigation within a periodic homogenization procedure. In this interface/surface model, the displacement vector is assumed to be continuous across the interface while the stress vector is considered to be discontinuous and satisfying the Laplace-Young equations. To solve these equations coupled to the classical mechanical equilibrium problem, a numerical simulation tool is developed in a two-dimensional (2d) context using the eXtended Finite Element Method (XFEM) and the Level-set functions. The developed numerical tool is then used to carry out a detailed analysis about the effect of nano-heterogeneities on the overall mechanical properties of a medium. The nano-heterogeneities are present

关键词： Interface/surface energy XFEM Level-set function Periodic homogenization Nano-voids/Nano-cavities Nano-cracks Nano-inclusions/Nano-heterogeneities

Physico-chemical and mechanical properties of Ti_3siC_2-based materials elaborated from siC/Ti by reactive spark plasma sintering

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Journal of Advanced Ceramics 2019年第1期8卷 47-61页

作者： Faten TURKI Houyem ABdeRRAZAK Frédéric sCHOENsTEIN Florent TêTARd Mohieddine ABdeLLAOUI Noureddine JOUINI Laboratoire des Matériaux Utiles Institut National de Recherche et d’Analyse Physico-chimique Laboratoire de sciences des procédés et Matériaux Université Paris 13 Sorbonne Paris Cité CNRS

In this paper, the synthesis of Ti_3 siC_2 from siC/Ti powder using reactive spark plasma sintering(R-sPs) in the temperature range of 1300-1400 ℃ is reported. The results show that the purity of Ti_3 siC_2 is improved up to 75 wt% when the holding time is increased from 10 to 20 min at1400 ℃. The thermodynamic and experimental results indicate that Ti_3 siC_2 formation takes place via the reaction of a pre-formed TiC phase with the silicides, formed from the eutectic *** analysis of mechanical behaviour indicates that samples with higher percentage of secondary phases exhibit higher microhardness and better resistance compared to the near single phase Ti_3 siC_2.

关键词： Ti3siC2 reactive spark plasma sintering(R-sPs) density mechanical properties

Numerical investigation of velocity ratio effect in combined wall and offset jet flows

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Journal of Hydrodynamics 2018年第6期30卷 1105-1119页

作者： Nidhal Hnaien salwa Marzouk Habib Ben Aissia Jacques Jay unité de Métrologie et des systèmes énergétiques Ecole National d'ingénieurs de Monastir Tunisie Centre de thermique de Lyon (CetHIL-UMR CNRs 5008) INSA de Lyon France

In the present work, we propose to numerically study a combined turbulent wall and offset jet flow(this combination will be denoted WOJ). several turbulence models were tested in this study: the standard k-w, ssT k-w, standard k-ε, RNG, and realizable k-ε model. A parametric study was performed to determine the effect of offset ratio H and the velocity ratio r on the longitudinal and transverse positions of the merge point(MP), the combined point(CP), the upper vortex center(UVC) and the lower vortex center(LVC). Correlations that predict the position of these characteristic points of the WOJ flow as a function of H and r have been provided. Results show that any increase in the velocity ratio causes a displacement of the MP, CP, UVC and LVC further upstream along the longitudinal direction. Concerning the transverse positions, the increase of velocity ratio results in a deviation of the merge point(MP) and the lower vortex center(LVC) toward the strong jet(LWJ) whereas the transverse position of combined point(CP) and the upper vortex center(UVC) is almost independent of the velocity ratio.

关键词： Finite volume combined point merge point offset jet velocity ratio

degradation of direct azo dye by Cucurbita pepo free and immobilized peroxidase

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Journal of Environmental sciences 2013年第6期25卷 1235-1244页

作者： Nabila Boucherit Mahmoud Abouseoud Lydia Adour Université Mouloud Mammeri Laboratoire de Biomatériaux et de Phénomènes deTransports Université Dr.Yahia Fares Laboratoire de Biomatériaux et de Phénomènes de Transports Université Dr.Yahia Fares Laboratoire de Génie de la Réaction Faculté de Génie Mécanique et Génie des ProcédésUniversité Houari Boumediene Laboratoire des Biotechnologies Environnementales et Génie des procédés

Enzymatic decolourization of the azo dye, direct Yellow （dY 106） by Cucurbita pepo （courgette） peroxidase （CP） is a complex process, which is greatly affected by pH, temperature, enzyme activity and the concentrations of H202 and dye. Courgette peroxidase was extracted and its performance was evaluated by using the free-CP （FCP） and immobilized-CP （ICP） forms in the decolourization of dY106. Immobilization of peroxidase in calcium alginate beads was performed according to a strategy aiming to minimize enzyme leakage and keep its activity at a maximum value by optimizing sodium alginate content, enzyme loading and calcium chloride concentration. The initial conditions ~it which the highest dY106 decolourization yield was obtained were found at pH 2, temperature 20~C, H202 dose 1 mmol/L （FCP） and 100 mmol/L （ICP）. The highest decolourization rates were obtained for dye concentrations 50 mg/L （FCP） and 80 mg/L （ICP）. Under optimal conditions, the FCP was able to decolorize more than 87% of the dye within 2 min. While with ICP, the decolourization yield was 75% within 15 rain. The decolourization and removal of dY106 was proved by UV-Vis analysis. Fourier transform infrared （FF-IR） spectroscopy analysis was also performed on dY106 and enzymatic treatment precipitated byproduct.

关键词： Cucurbita pepo peroxidase immobilization decolourization azo dye

Evaluation of stress intensity factors for bi-material interface cracks using displacement jump methods

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Acta Mechanica sinica 2017年第6期33卷 1051-1064页

作者： K. C. Nehar B. E. Hachi F. Cazes M. Haboussi Laboratoire de développement en mécanique et matériaux (LdMM) Université de Djelfa PB 3117 Djelfa Algeria Laboratoire des sciences des procédés et des Matériaux (LsPM) UPR 3407 CNRS Université Paris 13 Paris France

The aim of the present work is to investigate the numerical modeling of interfacial cracks that may appear at the interface between two isotropic elastic materials. The extended finite element method is employed to analyze brittle and bi-material interfacial fatigue crack growth by computing the mixed mode stress intensity factors(sIF). Three different approaches are introduced to compute the sIFs. In the first one, mixed mode sIF is deduced from the computation of the contour integral as per the classical J-integral method,whereas a displacement method is used to evaluate the sIF by using either one or two displacement jumps located along the crack path in the second and third approaches. The displacement jump method is rather classical for mono-materials,but has to our knowledge not been used up to now for a bimaterial. Hence, use of displacement jump for characterizing bi-material cracks constitutes the main contribution of the present study. several benchmark tests including parametric studies are performed to show the effectiveness of these computational methodologies for sIF considering static and fatigue problems of bi-material structures. It is found that results based on the displacement jump methods are in a very good agreement with those of exact solutions, such as for the J-integral method, but with a larger domain of applicability and a better numerical efficiency(less time consuming and less spurious boundary effect).

关键词： Bi-material interface crack Mixed mode stress intensity factor displacement jump X-FEM Fatigue crack growth

Experimental study of the effects of a transversal air-flow deflector in electronics air-cooling

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Journal of Thermal science 2011年第1期20卷 76-81页

作者： M.REBAY A.ARFAOUI J.PAdeT R.BEN MAAd Université de Reims GRESPI/lab.de ThermomécaniqueFaculté des sciencesBP 103951687 ReimsFrance Laboratoire d'Energétique et Transferts thermique et Massique Faculté des sciences2092 Manar IITunisia

This paper presents an experimental investigation of the influence of a transversal flow deflector on the cooling of a heated block mounted on a flat *** deflector is inclined and therefore it guides the air flow to the upper surface of the *** configuration is simulating the air-cooling of a rectangular integrated circuit or a current converter mounted on an electronic *** electronic component is assumed dissipating low heat power,as such,air forced convection is still a sufficient cooling way even without fan or heat sink on the *** measurements are given by hot and cold wires anemometers and by an InfraRed *** results give details of the effects of the deflection on the hydrodynamic and the thermal fields on and over the block for different inclination *** show that the deviation caused by the deflector may significantly enhance the heat transfer from the *** is also able to avoid local overheating of the electronic *** heat transfer rate and homogenised temperature are shown to be obtained with an inclination angle =30°.

关键词： Electronic cooling infrared imaging hot wire anemometer upward facing step backward facing step

Production of liquid bio-fuel from catalytic de-oxygenation:Pyrolysis of beech wood and flax shives

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燃料化学学报 2019年第2期47卷 153-166页

作者： Chetna Mohabeer Luis Reyes Lokmane Abdelouahed stéphane Marcotte Jean-Christophe Buvat Lucette Tidahy Edmond Abi-Aad Bechara Taouk Normandie Univ INSA Rouen NormandieUNIROUENLaboratoire de Sécurité des Procédés Chimiques Normandie Univ INSA Rouen NormandieUNIROUEN Université du Littoral Cte d'Opale Unité de Chimie Environnementale et Interactions sur le Vivant

This study presents a detailed analysis of the catalytic de-oxygenation of the liquid and gaseous pyrolytic products of two biomasses (beech wood and flax shives) using different catalysts (commercial HZsM-5 and H-Y,and lab-synthesised Fe-HZsM-5,Fe-H-Y,Pt/Al2O3 and CoMo/Al2O3). The experiments were all conducted in a semi-batch reactor under the same operating conditions for all feed materials. Bet specific surface area,BJH pore size distribution and FT-IR technologies have been used to characterise the catalysts,while gas chromatography-mass spectrometry (GC-Ms),flame ionisation detection (GC-FId) and thermal conductivity detection (GC-TCd) were used to examine the liquid and gaseous pyrolytic products. It was firstly seen that at higher catalyst-to-biomass ratios of 4∶1,de-oxygenation efficiency did not experience any further significant improvement. FeHZsM-5 was deemed to be the most efficient of the catalysts utilised as it helped reach the lowest oxygen contents in the bio-oils samples and the second best was HZsM-5. It was also found that HZsM-5 and H-Y tended to privilege the decarbonylation route(production of CO),whilst their iron-modified counterparts favoured the decarboxylation one (production of CO2) for both biomasses studied. It was then seen that the major bio-oil components (carboxylic acids) underwent almost complete conversion under catalytic treatment to produce mostly unoxygenated aromatic compounds,phenols and gases like CO and CO2. Finally,phenols were seen to be the family most significantly formed from the actions of all catalysts.

关键词： pyrolysis biomass catalytic treatment de-oxygenation bio-oil upgrading

Numerical study of Greenhouse Nocturnal Heat Losses

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Journal of Thermal science 2011年第4期20卷 377-384页

作者： F.Berroug E.K.Lakhal M.El Omari M.Faraji H.El Qarnia Laboratoire d'Automatique de l'Environnement et procédés de Transfert UniversitéCadi AyyadFacultédes Sciences Semlalia-Département de PhysiqueMarrakech-MarocAffiliéau CNRSTURAC 28 Laboratoire de Physique des Materiaux MicroelectroniqueAutomatique et TechniqueDepartement de PhysiquesFaculte des Sciences Ain ChockUniversite Hassan IICasablanca-Maroc

In this study we quantify and analyze different components of nocturnal losses from a heated greenhouse with the presence of vegetation for typical winter weather conditions in Marrakesh-Morocco,using a non linear model,based on the greenhouse heat and mass *** was found that 12% of the total input heat was dissipate as a sensible and latent leakage losses,66% was lost by convective exchange through air-inner *** gain of energy at the inner-cover is dissipated at the outer-cover by radiation(66%)and convection(34%).This results point toward some practical measures to reduce heat losses:increasing air tightness,using covering materials with low-emissivity in the long wave band or putting up an external thermal curtain should provide significant energy savings.

关键词： Greenhouse energy balance heat losses numerical analysis.

Evaluating organic acids as alternative leaching reagents for rare earth elements recovery from NdFeB magnets

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Journal of Rare Earths 2023年第4期41卷 621-631页

作者： sahar Belfqueh Alain seron simon Chapron Guilhem Arrachart Nourredine Menad BRGM Direction de l'Eaude l'Environnementdes Procédés et AnalysesOrleansFrance ICsM Univ.MontpellierCEACNRSENSCMMarcouleFrance

This study proposes an advanced leaching method using organic acids to recover rare earth elements(REEs)from NdFeB permanent magnets from end-of-life computers hard disk drives(Hdds).The end-oflife Hdds were first dismantled in order to recover NdFeB magnets,which were then thermally demagnetized at 350℃during 30 min before crushing in a ball mill under inert *** electron microscopy/energy dispersive X-ray spectroscopy(sEM/Eds)analyses performed on the NdFeB magnets show the heterogeneous structure containing the major matric phase Nd_(2)Fe_(14)B and the REEsrich phase containing Nd and Pr ***,X-ray diffraction(XRd)and Mossbauer spectroscopy(Ms)analyses on the ground NdFeB magnet show that grinding NdFeB magnets under inert atmosphere helps to minimize its *** analysis shows that the composition of the ground sample is Nd:22.8 wt%,Pr:3.3 wt%,dy:1.2 wt%,Fe:62.6 wt%,Co:1.5 wt%,B:0.9 wt%,Ni:0.6 wt%.diagrams of speciation and equilibrium phases(E_(h) ***)were calculated to determine the predominance of the formed species in the REEs-organic acids *** influence of the organic acid type(acetic acid,formic acid,citric acid and tartaric acid),the acid concentration(10 vol%,up to saturation),and the solid/liquid(s/L)ratio(0.5%-10%)on NdFeB magnets leaching was investigated employing an optimal experimental design conceived by the statistical software *** acid(CH_(3)COOH)shows the highest leaching performance of REEs,allowing leaching yields over 90%for Nd,dy and Pr in the acid concentration range of 1.6-10 mol/L and the s/L ratio range of 0.5%-5%at a temperature of 60℃.The results presented in this investigation suggest that REEs can be recovered from magnets of end-of-life Hdds using an eco-friendly method assisted by organic acids.

关键词： NdFeB magnets Rare earth elements Leaching Organic acids Acetic acid