Publications des chercheurs de la Division « Analyse de l’Eau et du Sol »

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Publications Internationales

Effect of acidic and ionic groups on the swelling and thermal behavior of poly (2-hydroxyethyl acrylate) based hydrogels.

N.Baït, B.Grassl, S.Djadoun

American Chemical Society (ACS), Polymeric Materials: Science and Engineering, 97 (2007) 424-425.

Abstract Abstract: Effect of acidic and ionic groups on the swelling and thermal behavior of poly (2-hydroxyethyl acrylate) based hydrogels



Hydrogel nanocomposites as pressure-sensitive adhesives for skin-contact applications

  1. Baït, B. Grassl, C. Derail, A. Benaboura

Soft Matter  7 (2011) 2025-2011

Abstract: Hydrogel nanocomposites as pressure-sensitive adhésives for skin-contact applications  

Graphical Abstract



Tailoring the adhesion properties of polyacrylamide-based hydrogels. Application for skin contact

  1. Baït,B. Grassl, A. Benaboura, C. Derail

Journal of Adhesion Science and Technology, 27 ( 2013) 1032-1047.

Abstract: Tailoring the adhesion properties of polyacrylamide-based hydrogels. Application for skin contact

Graphical Abstract

 



Milligels Synthesis and Characterization: Mebeverine Hydrochloride Uptake and Release

  1. Baït, B. Grassl, and A. Benaboura

Springer International Publishing AG 2018, Proceedings of the Third International Symposium on Materials and Sustainable Development, (2018) 1-6, https://doi.org/10.1007/978-3-319-89707-3_43

Abstract: Milligels Synthesis and Characterization: Mebeverine Hydrochloride Uptake and Release



Dynamic Rheology Study of In-situ Gelation Process of Polyacrylamide-Montmorillonite Composite Hydrogels

  1. Baït, B. Grassl, and A. Benaboura

Springer International Publishing AG 2018, Proceedings of the Third International Symposium on Materials and Sustainable Development, (2018) 1-7, https://doi.org/10.1007/978-3-319-89707-3_44.

Abstract Dynamic Rheology Study of In-situ Gelation Process of Polyacrylamide-Montmorillonite Composite Hydrogels



Coupling Ultrasound with Enzyme-Assisted Extraction of Essential Oil from Algerian Artemisia herba-alba Asso.

  1. Agouillal,H. Moghrani, N. Nasrallah,; Z. Hanapi, Z. Mat. Taher, H. A. El-Enshasy,

Journal of Scientific and Industrial Research JSIR, 77 (2018) http://nopr.niscair.res.in/handle/123456789/44801.



Characteristics of the Effluent Wastewater in Sewage Treatment Plants of Malaysian Urban Areas.

Ali H. Sabeen, N. Ngadi, Z. Zainon Noor, A. Bolanle Raheem, F. Agouillal, Abubaker A. Mohammed, B. Isah Abdulkarim.

Chemical Engineering Transactions. 63 (2018). http://www.aidic.it/cet/18/63/116.pdf

Abstract: Characteristics of the Effluent Wastewater in Sewage Treatment Plants of Malaysian Urban Areas.



Effect of additives on Pleurotus ostreatus Growth on Agar medium.

Parisa Maftoun, Roslinda Abd Malek, Helmi Johari Masry, Farid Agouillal, Avnish Pareek, Siti Zulaiha Hanapi, Hesham A. El Enshasy ;

Journal of Pharmacy and Biological Sciences (IOSR-JPBS), 12  (2017) 106-110. https://www.researchgate.net/publication/317494112_Effect_of_additives_on_Pleurotus_ostreatus_Growth_on_Agar_medium

Abstract: Effect of additives on Pleurotus ostreatus Growth on Agar medium.



A Review of Genetic Taxonomy, Biomolecules Chemistry and Bioactivities of Citrus Hystrix DC.

Farid Agouillal, Zarani M. Taher, Houria Moghrani, Noureddine Nasrallah and Hesham El Enshasy.

Biosciences Biotechnology Research Asia. Biosci Biotech Res Asia. 14 (2017),

http://www.biotech-asia.org/vol14no1/a-review-of-genetic-taxonomy-biomolecules-chemistry-and-bioactivities-of-citrus-hystrix-dc/



L’état qualitatif  et quantitatif  des ressources en eau  de la wilaya de Bejaia.

  1. H. Bir , K. Madani, B. Merzouk.

Revue Eau et Climat au Maghreb N° 1 Université de Rouen (2012).

Résumé: L’état qualitatif  et quantitatif  des ressources en eau  de la wilaya de Bejaia



Spatial and temporal variability of groundwater  quality of an Algerian aquifer: the case of Soummam Wadi.

  1. Benhamiche, L. Sahi, S. Tahar, H. Bir, Kh. Madani, B. Laignel

Hydrological Sciences Journal (2014).   DOI: 10.1080/02626667.2014.966723.



Particulate Flow at the Mouth of the Soummam  Watershed (Algeria).

  1. Allili-Ailane, B. Laignel, N. Adjeroud, H. Bir, Kh. Madani

Published online 00 Month 2015 in Wiley Online Library (wileyonlinelibrary.com) (2015).  DOI 10.1002/ep.12210.



Heat transfer correlation of viscoplastic fluid flow between two parallel plates and in a circular pipe with viscous dissipation

  1. Berabou, Y. K. Benkahla, N. Labsi, S-E. Ouyahia, A. Boudiaf,

Journal of the Brazilian Society of Mechanical Sciences and Engineering 404 (2018)40-48

https://doi.org/10.1007/s40430-018-1321-3.

Abstract: Heat transfer correlation of viscoplastic fluid flow between two parallel plates and in a circular pipe with viscous dissipation



Numerical Study of the Flow in a Square Cavity Filled with Carbopol-TiO2 Nanofluid,

S-E. Ouyahia, Y. K. Benkahla, Welid Berabou, Ahlem Boudiaf,

Powder Technology 311(2017) 101–11,

https://doi.org/http://dx.doi.org/10.1016/j.powtec.2017.01.026.

Abstract: Numerical Study of the Flow in a Square Cavity Filled with Carbopol-TiO2 Nanofluid,

Graphical abstract



Convection mixte dans une conduite traversé e par un fluide de Bingham

  1. Labsi, Y. K. Benkahla, Welid Berabou

Editions universitaires europeennes EUE (2017) 60p

Résumé: Abstract: Convection mixte dans une conduite traversé e par un fluide de Bingham



Convection mixte lors de l’ecoulement d’un fluide de bingham au sein d’une conduite cylindrique horizontale

  1. Labsi, Welid Berabou,Y. K. Benkahla, M. Akkar, A. Mansouri,

Mediterranean Journal of Modeling and Simulation 03 (2015) 80-86,

Résumé  Abstract: Convection mixte lors de l’ecoulement d’un fluide de bingham au sein d’une conduite cylindrique horizontale



Thermal characterization of the casson fluid flow in a circular pipe by considering viscous dissipation,

  1. Berabou, Y. K. Benkahla, A. Boutra, N. Labsi,

Physical and Chemical News 67(2013) 57-62,

http://www.pcnjournal.com/136710_1808.htm

Abstract  Abstract: Thermal characterization of the casson fluid flow in a circular pipe by considering viscous dissipation,



Convection naturelle d’un nanofluide confiné dans une enceinte triangulaire : Effet du fractionnement et de la position de la source de chaleur

S-E. Ouyahia, Y. K. Benkahla, W. Berabou, M. Benzema, A. Boudiaf,

Association Française de Mécanique AFM (2017), 23ème Congrès Français de Mécanique CFM2017, Lille, 28 Août au 1er Septembre 2017,

http://documents.irevues.inist.fr/bitstream/handle/2042/63185/130710.pdf?sequence=1

Abstract  Abstract: Convection naturelle d'un nanofluide confiné dans une enceinte triangulaire



Convection mixte lors de l’écoulement d’un fluide à contrainte seuil au sein d’un tube cylindrique incliné

  1. Berabou, Y. K. Benkahla, N. Labsi, A. Boudiaf, S-E. Ouyahia,

Société Française de Thermique (2017), 25ème Congrès français de thermique, Marseille, 30 mai au 02 juin 2017

http://www.sft.asso.fr/Local/sft/files/148/91.pdf

Résumé  Abstract: Convection mixte lors de l’écoulement d’un fluide à contrainte seuil au sein d’un tube cylindrique incliné



Etude de l’impact de la dissipation visqueuse sur le transfert thermique lors de l’écoulement d’un fluide viscoplastique

  1. Berabou, Y. K.Benkahla, N. Labsi, S-E. Ouyahia,

Société Française de Thermique (2015), Congrès français de thermique 2015, La Rochelle, 26-29 mai 2015,

http://www.sft.asso.fr/Local/sft/dir/user-3775/documents/actes/Congres_2015/Communications/41950-fichier4.pdf

Résumé  Abstract: Etude de l'impact de la dissipation visqueuse sur le transfert thermique lors de l'écoulement d’un fluide viscoplastique



Effet du champ magnétique sur la convection naturelle dans une cavité inclinée remplie d’un nanofluide

S-E. Ouyahia, Y. K. Benkahla, M.Benzema, W. Berabou

Société Française de Thermique (2015), Congrès français de thermique 2015, La Rochelle, 26-29 mai 2015

http://www.sft.asso.fr/Local/sft/dir/user-3775/documents/actes/Congres_2015/Communications/42090-fichier4.pdf

Résumé  Abstract: Effet du champ magnétique sur la convection naturelle dans une cavité inclinée remplie d’un nanofluide



Effet de la dissipation visqueuse sur les caractéristiques thermiques de l’écoulement d’un fluide de Casson au sein d’une conduite cylindrique

  1. Berabou, Y. K. Benkahla, N. Labsi, A. Boutra,

Société Française de Thermique (2013),

http://www.sft.asso.fr/Local/sft/dir/user-3775/documents/actes/congres_2013/articles/6054.pdf

Résumé  Abstract: Effet de la dissipation visqueuse sur les caractéristiques thermiques de l’écoulement d’un fluide de Casson au sein d’une conduite cylindrique



Chromium (VI) photoreduction under visible and sunlight irradiation overbismuthferrites Bi2Fe4O9 photocatalyst.

  1. KebirA. BoudjemaaY. AzoudjM. SehailiaK. Bachari,

The Canadian Journal of Chemical Engineering, 96,(2018) 2292-2298.

Abstract  Abstract: Chromium (VI) photo‐reduction under visible and sunlight irradiation overbismuth‐ferrites Bi2Fe4O9 photo‐catalyst.

Graphical abstract



Efficient photo–catalytic degradation of malachite green using nickel tungstate material as photo–catalyst,

  1. Helaïli; A. Boudjamaa; M. Kebir; K. Bachari,

Environmental Science and Pollution Research, 24 (2017) 6481–6491.

Abstract  Abstract: Efficient photo–catalytic degradation of malachite green using nickel tungstate material as photo–catalyst,



Photodegradation of organic pollutants in water and green hydrogen production via methanol photoreforming of doped titanium oxide nanoparticles.

A.Boudjemaa, H. Bahruji, M.Kebi, S.Prashar, K.Bachari, M.Fajardo, S.Gómez-Ruiz,

Science of The Total Environment,  563–564 (2016) 921-932.

Abstract 

Graphical Abstract



M-substituted (M = Co, Ni and Cu) zinc ferrite photo-catalysts for hydrogen production by water photo-reduction

A.Boudjemaa, I.Popescu, T. Juzsakova, M. Kebir, N.Helaili, K.Bachari, I-C. Marcu, International Journal of Hydrogen Energy,  41  (2016) 11108-11118

Abstract  Abstract : M-substituted (M = Co, Ni and Cu) zinc ferrite photo-catalysts for hydrogen production by water photo-reduction



Valorization of Inulaviscosa waste extraction, modeling of isotherm, and kinetic for the tartrazine dye adsorption

  1. Kebir, M. Trari, R. Maachi, N. Nasrallah, A. Amrane

Journal Desalination and Water Treatment,  54 (201

Abstract  Abstract: Valorization of Inulaviscosa waste extraction, modeling of isotherm, and kinetic for the tartrazine dye adsorption



Enhancement photo-catalytic degradation of benzoic acid using the heterosystem NiCo2O4/ZnO.

M.Kebir, A.Boudjemaa, K.Bachari.

Materials Science in Semiconductor Processing,  39 (2015) 300-307

Abstract  Abstract: Enhancement photo-catalytic degradation of benzoic acid using the heterosystem NiCo2O4/ZnO.



Relevance of a hybrid process coupling adsorption and visible light photocatalysis involving a new hetero-system CuCo2O4/TiO2 for the removal of hexavalent chromium.

M.Kebir, M.Trari, R.Maachi, N.Nasrallah, B.Bellal, A.Amrane.

Journal of Environmental Chemical Engineering,  3 (2015) 548-559

Abstract  Abstract: Relevance of a hybrid process coupling adsorption and visible light photocatalysis involving a new hetero-system CuCo2O4/TiO2 for the removal of hexavalent chromium.



Brevet 

Développement d’un nouveau catalyseur basique, à base de Nickel (Ni), dopé par le Strontium (Sr) via la méthode d’intercalation, pour le reformage sec du méthane

  1. Chami, R. Chebout, K. Bachari

Brevet d’invention N° 8485/2013. Institut National Algérien de la Propriété Industrielle www.inapi.org

But de l’invention:  Brevet: Développement d’un nouveau catalyseur basique, à base de Nickel (Ni), dopé par le Strontium (Sr) via la méthode d’intercalation, pour le reformage sec du méthane



Publications Nationales

Rhéologie des hydrogels polyacrylamide/montmorillonite

N.Baït, B.Grassl, A.Benaboura

Journal of Materials, Processes and Environment December edition. Vol.2. No2. (2014) ISSN : 2335-1020

Résumé  Abstract: Rhéologie des hydrogels polyacrylamide/montmorillonite

 



Hydrogels Polyacrylamide-Montmorillonite. Application au piégeage-relargage du Chlorhydrate de Metformine  

N.Baït, B.Grassl, A.Benaboura,

Actes du 2ème Colloque International sur les Matériaux et le Développement Durable, ISBN 978-9931 -9090-6-2

Résumé  Hydrogels Polyacrylamide-Montmorillonite. Application au piégeage-relargage du Chlorhydrate de Metformine  



Wastewater Treatment Using Extraction Industries Wastes: Methyl Orange Removal By Bio-sorbent.

  1. Agouillal, H. Moghrani, N. Nassrallah,  R.Maachi

Journal of Materials, Processes and Environment 3 13-19. https://www.asjp.cerist.dz/en/article/15060

Abstract  Abstract: Wastewater Treatment Using Extraction Industries Wastes: Methyl Orange Removal By Bio-sorbent.

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Polyelectrolyte  hydrogels  based  on (2-hydroxyethyl  acrylate) monomer  copolymerized  with  itaconic  acid,  sodium  itaconate  or potassium  itaconate  were  prepared  by  free-radical  polymerization iin  aqueous  media,  using  N,N-methylene-bis-acrylamide  as crosslinker. The  DSC  analysis  showed  from  the  glass  transition temperatures of  these hydrogels  that the chain mobility is  affected by  the  acidic  or  ionic  groups.  According  to  TGA  thermogramms and  DTG  curves,  the  incorporation  of  itaconic  acid  within  the hydrogel generates a slight early degradation of PHEA network. This  study  showed  that  P(HEA-IA10)  is  the  least  stable network  in  the  30-50  %  weight  loss  range.  Above  this  range, P(HEA-IA-INay%)  or  P(HEA-IA-IKy%)  hydrogels  showed practically  the  same  thermal  stability  ,  slightly  less  than  that  of P(HEA-IA10) network. In an agreement with DSC  analysis, Swelling studies showed that The  higher  is  the  amount  of  the  counterion  of  large size,  the stronger it bounds to P(HEA-IA10) polymeric chains , lowering thus its flexibility

This study investigates the effects of monodisperse polystyrene nanoparticle fillers on the
network formation, rheological properties and adhesion performance of hydrogel
nanocomposites based on polyacrylamide and poly(acrylamide-hydroxyethyl methacrylate).
We demonstrated a simultaneous increase in elasticity and tack of these humid composite
materials. A 1H-NMR kinetic study showed quasi-total conversion of these monomers during
the polymerization–reticulation process and the formation of inhomogeneities within the
hydrogel network structure due to the difference in reactivity ratios of the comonomers:
acrylamide (AM) and hydroxyethyl methacrylate (HEMA)(rAM = 0.41 ± 0.01 and rHEMA =
7.4 ± 0.3). The rheological properties of these materials were found to be affected by their
chemical composition (HEMA content, presence of nanoparticles and heterogeneities). We
investigated the adhesion properties of our materials using a probe test tack. Measurements
were carried out on a human skin substitute to compare with metal and investigate the

In the present study, we investigated the adhesive performances of polyacrylamide-based hydrogels intended to be used as dermatological patches. Accordingly, we have prepared conventional copolymer poly(acrylamide-co-hydroxyethyl methacrylate) hydrogels and nanocomposite copolymer poly(acrylamide-co-hydroxyethyl methacrylate) hydrogels filled with poly(butyl acrylate) nanoparticles. We evaluated their adhesive properties when they were applied to different substrates (equivalent human skin, stainless steel) using a probe tack test. The adhesion energy was found to be related to the chemical composition and the rheological properties of the hydrogels which were also measured.

 

Abstract

This study describes the millifluidic-based synthesis of conventional Polyacrylamide (PAM), Polyacrylamide-Sodium Montmorillonite (PAMNaMMT) and Polyacrylamide-Organo-modified Montmorillonite (PAMOMMT) composite milligels. These hydrogel particles with millimeter size are intended to be used for the design of Drug Delivery Systems (DDS) combining hydrogels and Clay performances. The composite hydrogels structure, the interactions between the PAM chains and the Clay and the networks thermal behavior were evidenced by Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) respectively. PAM, PAM-NaMMT and PAM-OMMT milligels potential loading and release of Mebeverine Hydrochloride, taken as a model molecule, was investigated by UV Spectroscopy. This potential was examined as a function of the release medium, the networks chemical composition, the Montmorillonite (MMT) nature and its content.

Abstract

The composition of the essential oil (EO) of Artemisia herba-alba Asso, extracted by Hydro-Distillation (HD) and by coupling Ultrasound with Enzyme-Assisted Extraction (UE-AE) prior to HD from the plant’s aerial parts were analyzed by GC-MS. Antibacterial, antifungal and antioxidant activities of the obtained EOs were evaluated. The yield of EO extraction after pretreatment of the desert wormwood leaves by coupling ultrasound with enzymes was in the range of 1.56%±0.07 compared to 1.01% ±0.08 in HD process; also, the total time necessary to complete EO extraction is 180min for HD and 120min for UE-AE. GC–MS profiling of the EOs showed changes in chemo type obtained by HD from camphor/1,8-cineole/a-thujone/chrysanthenone to a new chemotype in the case of UE-AE: camphor/a-thujone/1,8-cineole/filifolone; Then, an increasing of filifolone, a-thujone, 3-octyne and cis-limonene oxide characterize the UE-EO. The antifungal activity of the EO has slightly increased when extracted by UE-AE, however, both antibacterial and antioxidant activities were interestingly increased.

 

Abstract

Recently, a lot of domestic wastewater is being generated due to the rise in the population in most urban areas in Malaysia. This implies that more contaminations are being produced which are likely to affect human health. The purpose of this research was to analyze the level of contaminants in the final treated wastewater from the sewage treatment plants in Malaysian urban areas and compare it with Malaysian standard A and B effluent discharged. The specimens used for the analysis were obtained from three wastewater sewage treatment plants in Johor (A), Kuala Lumpur (B), and Penang(C). Specimens were examined using chemical oxygen demand (COD) Vials, Nitrate Nitrogen ammonia vial, and total Phosphorus vial. The Hach DR 5000 UV-V Laboratory Spectrophotometer was used to measure the amount of COD, Nitrate, Nitrate, and Phosphorus. Also, the pH, turbidity, and BOD5 were done utilizing dissolved Oxygen machine and Lovibond Turbidity Meters. The level of BOD, COD were treated well and discharged according to the used standards. The findings revealed that phosphorus in plant c with 12 mg/L in February, Nitrate in plant A 22 mg/L in January, Nitrite in plant A with 18.2 mg/L in February, 19.4 mg/L in February in plant B and16 mg/L in February were found little greater than the prescribed effluent standard of Malaysian wastewater. It was recommended that the final treated water should be frequently and thoroughly treated for the purpose of reusing it for secondary intent. This study has important implications for protecting human health and the environment by identifying the effluent sewer treatment plant that has no proper treatment capability to produce water that is fit for domestic and irrigation purpose.

 

Abstract

Mushrooms health benefit was recognized in the Orient from several thousand years ago as globally consumption and has third largest commercially production. The genus Pleurotus (oyster mushroom) is an organoleptic fast growing fungus which belongs to basidiomycota group. Although 70 species is discovered until now for this genus, but only few of them are available in market such as Pleurotus florida, P. sajor-caju and P. ostreatus. They have been used in human diet throughout the world due to their rich nutrients such as protein, fiber carbohydrate, minerals, vitamins and lipid. It should be noted that low amount calories, Sodium, fat and cholesterol is reported in this genus. Many pharmaceutical companies in the Far East and China are viewing the medicinal mushrooms as a rich source of innovative biomedical molecules. These molecules can be extracted from different part of oyster mushroom such as fruiting body, mycelia and culture broth. Mainly they are biopolymers including polysaccharides, proteins and nucleic acids as they are more variable to carry biological information. The medicinal properties of Pleurotus spp studied by several authors, as a result antitumor, immunomodulating, antiviral, antibacterial, antigenotoxic, antioxidant, antiinflammatory, hypocholesterolamic, antihypertensive, antiinociceptive, anti-hyperglycaemic, anti-platelet-aggregating, antihepatoma, anti poliferative and antiatherosclerotic. In this chapter, biodivertsity of genus Pleurotus will be discussed regarding nutritional and bioactive compounds. Furthermore the prospective of oyster mushroom for therapeutic application and concept will be highlighted.

Résumé

L’eau est un élément indispensable à la vie de l’homme, à ses activités domestiques, agricoles et industrielles. L’objectif de notre travail est d’étudier l’état qualitatif et quantitatif des ressources en eau dans la wilaya de Bejaia qui est une région côtière du Centre-est Algérien, son climat est de type méditerranéen caractérisé par un hiver doux et un été chaud et sec. Les résultats ont montré que cette wilaya a des potentialités importantes mais soumises à plusieurs contraintes (pollution, l’envasement des barrages, les fuites, la surexploitation des eaux souterraines,…etc). Du point de vue qualitatif également, les eaux qu’elles soient de surface ou souterraines, se dégradent de façon continue en liaison avec l’environnement.

Abstract

In Algeria, the particulate flow in rivers is poorly quantified in the wadi due to the absence and the non standardization of the acquisition of measurement data. Most studies on particulate flows are quantified from time series of hydrometric stations. The present study is based on weekly sampling of water at the mouth of the Soummam watershed for the hydrological year 2011/2012. The sediment flux is analyzed from measurements of suspended solids (SS). The determination coefficients between the annual and seasonal “ liquid flow–solid flow-” relationships vary from 75% to 82%, respectively. During this period, the watershed of 9125 km2 has provided a solid input estimated to 4.9 3 106 t yr-1, hence a specific flow of 538 t km2 yr-1. In general, autumn floods were characterized by high concentrations of SS, which varies from 820 to 1275 mg L-1. The most important sediment transport volumes were observed during the period of December to February, this period is characterized by strong turbulence, due to extreme flows, favoring the largest volumes of solid transport.

Abstract

The present paper investigates the laminar forced convection heat transfer for a generalized Casson fluid flow through a horizontal circular pipe and between two parallel plates maintained at a uniform wall temperature. This study focuses on the effect of yield stress and flow index as well as Peclet number on thermal transport characteristics for both the entrance and the fully developed regions. Because of the viscous character of this kind of fluids, viscous dissipation is taken into account. The regularized Papanastasiou model is considered to avoid the discontinuous-viscosity behavior of the fluid. The governing equations are discretized by means of the finite volume method using the power law scheme. The numerical simulations are conducted using a source code based on the FORTRAN language. The results show that the increase in the Peclet number leads to the increase in the heat transfer rate at the inlet. Furthermore, the Nusselt number decreases when the flow index increases and increases downstream when the Casson number increases. Heat transfer is also significantly improved when viscous dissipation is taken into account. A correlation is proposed at the end of the study; it gives the asymptotic Nusselt number over a wide range of the Casson number (0 ≤ Ca ≤ 20), when viscous dissipation is neglected and taken into account. The comparison between both geometrical configurations shows that, from a thermal point of view, it is more interesting to use parallel plates than a pipe.

Abstract

The present paper investigates numerically the free convection of a non-Newtonian carbopol-TiO2 nanofluid confined in a square cavity with vertical walls subject to uniform and constant heat flux and insulated horizontal walls. The rheological behavior is taken into account by combining the regularized Herschel-Bulkley-Papanastasiou model with the model of He et al. [1]. The partial differential equations governing fluid flow and heat transfer are discretized using the Finite Volume Method. The numerical experiments are carried out for a range of parameter values, namely, Rayleigh number 103-106, Herschel-Bulkley number 0-20, Prandtl number 10-1000, power law index 0.4-1.0 and nanoparticle solid volume fraction 0.0-0.09. The numerical results are presented in terms of streamlines, isotherms, unyielded plugs, velocity profiles and average Nusselt number. It is found that, all the problem parameters, except for the Prandtl number, have a significant effect on both the hydrodynamic and the thermal fields.

Résumé

La présente étude traite du transfert thermique en mode de convection mixte lors de l’écoulement d’un fluide viscoplastique de Bingham au sein d’une conduite cylindrique horizontale à section droite circulaire, mainte- nue à température constante et uniforme. Le travail numérique, basé sur la méthode des volumes finis, se focalise sur l’impact de l’intensité des forces de poussée sur le comportement hydrodynamique et thermique de l’écoulement. Les résultats montrent que la structure de l’écoulement se modifie avec l’augmentation du nombre de Grashof. Cette augmentation entraine l’amélioration du transfert thermique et l’augmentation de la perte de charge et ce, dans la zone intermédiaire de la conduite.

 

Abstract
La présente étude traite du transfert thermique en mode de convection mixte lors de l’écoulement d’un fluide viscoplastique de Bingham au sein d’une conduite cylindrique horizontale à section droite circulaire, mainte- nue à température constante et uniforme. Le travail numérique, basé sur la méthode des volumes finis, se focalise sur l’impact de l’intensité des forces de poussée sur le comportement hydrodynamique et thermique de l’écoulement. Les résultats montrent que la structure de l’écoulement se modifie avec l’augmentation du nombre de Grashof. Cette augmentation entraine l’amélioration du transfert thermique et l’augmentation de la perte de charge et ce, dans la zone intermédiaire de la conduite.

Abstract

The purpose of this work is to characterize, by means of finite volume method, the heat transfer of an incompressible Casson fluid flowing in a circular pipe maintained at uniform temperature. The study deals with the influence of Reynolds and Casson numbers on heat transfer. Because of the viscous character of this type of fluid, viscous dissipation is taken into account. The results show that the increase of the Reynolds number leads to the increase of the Nusselt number at the inlet. Furthermore, the latter is increased downstream when the Casson number increases. The introduction of viscous dissipation improves significantly heat transfer.

Abstract

We propose to study numerically the thermo-hydraulic characteristics of TiO2 water nanofluid filled in an isosceles triangular cavity. The inclined walls are isothermal cold, while the base is insulated. On the other hand, the cavity is provided with a hot isothermal heat source. The governing equations of this study are discretized by the finite volume method. A hybrid numerical scheme, Upwind-Centered, is used for the interpolation of dependent variables, especially the velocity and temperature fields. The presence of nanoparticles in the base fluid, water in this case, is modeled by the correlations proposed by He et al. (2009), and this through the effective thermal conductivity and dynamic viscosity of the nanofluid.

Numerical simulations are conducted to examine the effect of physical parameters such as the Rayleigh number and the volume fraction of the nanoparticles, as well as geometric parameters namely, fractionation and position of the heat source. The results are presented in term of cartography of streamlines and isotherms as well as the cavity average Nusselt number. The results show that increasing the Rayleigh number intensifies the velocity and temperature fields. Furthermore, the addition of nanoparticles improves the heat transfer rates but weakens the flow. Moreover, it is observed that some positions of the heat source increase the Nusselt number while others disadvantage it. At the end, the horizontal and vertical splitting of the heat source increases substantially the heat transfer in particular, for a vertical splitting.

Résumé

Le travail consiste en une étude numérique de la convection mixte d'un écoulement en développement simultané à l'intérieur d'une conduite incliné avec une température constante et uniforme sur sa surface externe. Le fluide est non-newtonien viscoplastique incompressible obéissant au modèle rhéologique de Casson généralisé et avec des propriétés constantes sauf dans le terme de gravité où l'hypothèse de Boussinesq est adoptée. L'écoulement est laminaire en régime permanent. La dissipation visqueuse est négligée. Les équations différentielles ont été intégrées et discrétisées selon l'approche des volumes finis. La procédure SIMPLER a été utilisée pour la résolution du système d’équations algébriques fortement couplées (température-vitesse et gradient axial de pression-vitesse). Cette étude a permis d’analyser l'effet des principaux paramètres du problème sur l'écoulement laminaire d'un fluide de Casson, en mode de convection mixte. En particulier, nous analysons l'influence de l'inclinaison de la conduite par rapport à l'horizontale et le taux de chauffage (à travers le nombre du Grashof), sur le développement des champs hydrodynamique et thermique du fluide ainsi que sur la distribution axiale de l’intensité d’échange thermique.

Résumé

Le transfert thermique dans les fluides non-newtoniens purement visqueux se rencontre souvent dans diverses industries (par exemple, de la chimie, de la pétrochimie et de la transformation des aliments). Ces fluides sont généralement traités sous des conditions d'écoulement laminaire en raison de leurs viscosités élevées. La présente étude numérique est effectuée pour prédire l’écoulement laminaire et stationnaire en mode de convection forcée, d’un fluide non-newtonien décrit par le modèle rhéologique de Casson généralisé, modifiée par Papanastasiou. Le fluide circulant entre deux plaques parallèles portées à des températures constantes et uniformes et à travers une conduite cylindrique isotherme. Le modèle mathématique est représenté par les équations de continuité, du mouvement et de l’énergie, avec prise en compte de la fonction de dissipation. Les propriétés physiques et rhéologiques du fluide sont supposées constantes et uniformes. Un code numérique basé sur la méthode des volumes finis a été élaboré pour intégrer le système d’équations non-linéaires régissant l'écoulement. Cette analyse a permis de mettre en évidence l’effet occasionné par la dissipation visqueuse à travers le nombre de Brinkman et la contrainte seuil sur la distribution du champ de température et également sur l’intensité de l’échange thermique entre le fluide et les parois. En tenant compte de la dissipation visqueuse. Les résultats obtenus montrent que l’accroissement de la contrainte seuil provoque une intensification de l’échange thermique, et ce dans les deux configurations considérées. Enfin, la contrainte seuil engendre de forts gradients de vitesse dans la zone cisaillée, située près de la paroi, qui sont à l’origine de l’auto réchauffement du fluide étant donné, la prise en compte de la dissipation visqueuse. En conséquence, pour un nombre de Brinkman donné (Br = 2), la structure du fluide sera très affectée par les valeurs élevées du nombre de Casson.

Résumé

Le présent travail consiste en une étude numérique de la magnétohydrodynamique de la convection naturelle, laminaire et stationnaire au sein d’une cavité carrée remplie d’un nanofluide Al2O3-eau. Cette cavité est soumise à un champ magnétique horizontal, constant et uniforme. Les parois verticales sont différentiellement chauffées tandis que les parois horizontales sont isolées thermiquement. Les équations régissant le problème physique sont discrétisées par la méthode des volumes finis et ce, en utilisant un schéma d’interpolation en loi de puissance. La conductivité effective et la viscosité effective du nanofluide sont calculées respectivement, par le modèle de Maxwell-Garnetts et celui de Brinkman. L’étude porte sur l’effet de paramètres physiques tels que le nombre de Rayleigh (103 ≼Ra ≼106), le nombre de Hartmann (0 ≼Ha ≼100) et la fraction volumique en nanoparticules (0,0 ≼ϕ ≼0,1) et d’un paramètre géométrique qui consiste en l’inclinaison de la cavité par rapport à l’horizontale (0° ≼ w≼60°). Les résultats obtenus montrent que les nombres de Rayleigh et de Hartmann ont un effet considérable sur les champs hydrodynamique et thermique. En outre, l’ajout des nanoparticules suscite des améliorations des performances thermiques au sein de l’enceinte. Par ailleurs, les champs hydrodynamique et thermique dépendent fortement de l’inclinaison de la cavité.

Résumé

L’étude présentée, porte sur l’analyse numérique des caractéristiques thermiques de l’écoulement stationnaire en mode de convection forcée, d’un fluide viscoplastique incompressible de Casson, dans une conduite cylindrique, maintenue à température uniforme. Elle est réalisée en utilisant un code de calcul, basé sur la méthode des volumes finis. Les résultats montrent l’influence exercée par les nombres de Reynolds et de Casson sur la distribution spatiale du champ thermique en présence et en l’absence de la fonction de dissipation. En présence de cette dernière, les températures moyennes réduites augmentent de manière monotone et dépassent l’unité (en valeur absolue).

Abstract

The photo‐catalytic reduction of Cr(VI) in aqueous solution was investigated over spinel ferrites Bi2Fe4O9 photo‐catalyst under both visible and solar light irradiation. The material was prepared by a low‐cost method and characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy dispersive x‐ray (EDX), Fourier transform infrared spectroscopy (FTIR), and diffuse reflectance spectroscopy (DRS). Electrochemical and photo‐electrochemical studies of the material were also explored. The Bi2Fe3O9 structure had a small band gap (2.05 eV), which allowed the material to absorb more visible light. The photo‐electrochemical characterization in the presence of Na2SO4 indicated that Bi2Fe4O9 is a n‐type semi‐conductor with a flat band of 0.77 V. The influence of the catalyst dose (0.25–1.5 g L−1), the initial concentration of Cr(VI) (25–125 mg L−1), and the irradiation source parameters on the photo‐catalytic performance of Bi2Fe4O9 were studied at pH 2. The results indicated that the reduction rate of Cr(VI) depended on the catalyst's mass and the initial concentration of Cr(VI). By comparing the photo‐reduction activity under visible, ultrasonic, and solar irradiation, it became apparent that the presence of solar light increased the reduction efficiency. The Cr(VI) reduction rate was remarkably different when a combination of sonication and photo‐catalysis was utilized. This work indicated that Bi2Fe4O9 can serve as a promising photo‐catalyst for the photo‐reduction of Cr(VI) under visible light irradiation.

Abstract

The present study focused on the evaluation of photo-catalytic and photo–electrochemical properties of the photo–catalyst based on nickel tungstate material prepared by a nitrate method through the degradation of malachite green (MG) dye's. The effect of catalyst loading and dye concentration was examined. Physico–chemical, optical, electrical, electrochemical, and photo–electrochemical properties of the prepared material were analyzed by X-ray diffraction (XRD), fourier transform–infrared spectroscopy (FTIR), BET analysis, optical reflectance diffuse (DR), scanning electron microscopy (SEM/EDX), electrical conductivity, cyclic voltammetry (CV), current intensity, mott–shottky, and nyquist. XRD revealed the formation of monoclinic structure with a small particle size. BET surface area of the sample was around 10 m2/g. The results show that the degradation of MG was more than 80%, achieved after 3 h of irradiation at pH 4.6 and with a catalyst loading of 75 mg. Also, it was found that the dye photo–degradation obeyed the pseudo-first order kinetic via Langmuir Hinshelwood model.

Abstract

A0.2Zn0.8Fe2O4 ferrites with A = Co, Ni and Cu were successfully prepared by co-precipitation followed by annealing at 650 °C. They were characterized by using XRD, EDX, BET, FTIR, RDS, electrical conductivity, Current-Potential, Mott–Schottky and Nyquist techniques and their photo-catalytic properties were evaluated in hydrogen production through water photo-reduction. XRD revealed the formation of cubic ferrospinel structures with particle sizes in the nano-range. BET surface areas of the ternary spinels were higher than that of the binary ZnFe2O4. The electrical conductivities of A0.2Zn0.8Fe2O4 were found to obey the Arrhenius law with activation energies of conduction between 0.17 and 0.31 eV. They were found to be n-type semiconductors with narrow band gap. The photo-catalytic results for hydrogen production indicated that the Co substitution dramatically enhances the catalytic activity of ZnFe2O4. This substituted zinc ferrite shows the highest photo-catalytic activity under visible light irradiation, which varies as follows: Co0.2Zn0.8Fe2O4 >> Ni0.2Zn0.8Fe2O4 > ZnFe2O4 > Cu0.2Zn0.8Fe2O4.

Abstract

The aim of this study was the tartrazine dye removal from aqueous solutions using a solid waste from the essential oil extraction of Inulaviscosa. Experiments carried out in batch mode showed that the adsorption depended on physical parameters such as pH, adsorbent dose, initial pollutant concentration, and temperature. The results of scanning electron microscopy and energy dispersion X-ray indicated that the potential to adsorb tartrazine dye onto I. viscosa was related to the adsorbent structure. The nature of the surface groups on the adsorbent was determined from the Fourier transform infrared spectroscopy and specific surface area. The dye retention was found to be pH-dependent and the tartrazine adsorption decreased with increasing pH over the pH range (1–6). The Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherm models were used to analyze the adsorption behavior. The maximum adsorption capacity was found to be ~43.1 mg g−1 at pH 2 and 298 K. Dye adsorption kinetic was well described by a pseudo-second-order model. The thermodynamic parameters indicated that the adsorption of tartrazine was spontaneous and endothermic, and the process was governed by physisorption owing to the low enthalpy. Therefore, I. viscosa is promising as a low-cost adsorbent for the dye removal from aqueous solutions.

Abstract

The present work focused on the degradation of benzoic acid in aqueous solutions using the heterosystem NiCo2O4/ZnO as a semi-conductor. The material NiCo2O4is prepared by a nitrate method and characterized by several techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR), reflectance diffuse (RD), electrical conductivity and the photo-electrochemical (PEC) characterizations. Under visible light, the benzoic acid degradation using a heterosystem NiCo2O4/ZnOis investigated. Several parameters are examined as the pH, the heterosystem ratio and the initial benzoic acid concentration. The results reveal that, as pH value increased from 2 to 6, the photo-degradation raised and the removal efficiencies attend the value 71%. The optimum results exhibited an enhancement photo-activity at a neutral pH and with a heterosystem ratio 50/50. The high efficiency is due to the present of unique structure constructed which increases the amount of electro-active sites and facilitates the electrolyte penetration via the electron transfer. Thus, the kinetic analysis showed that the photo-degradation rates can be approximated to be pseudo-first order, according to the Langmuir–Hinshelwood kinetics model.

 

Abstract

Chrome(VI) removal was investigated by adsorption onto an agricultural farm plant (Sauge) combined to photocatalysis onto the new hetero-system p-CuCo2O4/n-TiO2 in the presence of tartaric acid.In batch configuration, the equilibrium was reached after 3 h. Increasing the initial Cr(VI) concentration increased the adsorption capacity and decreased the efficiency removal and the optimal pH was found to be ∼2. Among the tested equilibrium isotherms, the Langmuir model led to the most accurate fit of experimental data. Adsorption kinetic data followed a pseudo-second order model and the intra-particle diffusion study revealed that the adsorption rate was not controlled by the diffusion step.

The photo-reduction of Cr(VI) onto the hetero-system CuCo2O4/TiO2 under visible light was studied to complete the water treatment operation. The optimal photocatalytic performance was found for 25 mg L−1 initial Cr(VI) concentration and pH ∼2. Under these conditions, the hetero-system favored hydrogen formation, with an evolved volume of 1.70 cm3 after 25 min. The contaminated industrial wastewater of tannery containing 2.25 mg L−1 was completely treated photo-catalytically.

The hybrid process (adsorption/photocatalysis) was tested and showed its efficiency. For 150 mg L−1 initial amount, removal yield increased from 45% if only adsorption was considered to 82.6% by the hybrid process in less time. Hence, the hybrid process constitutes an eco-friendly approach, since it involves low cost and environmental friendly waste materials for the adsorption step (Sauge) and the hetero-system CuCo2O4/TiO2 allowing photochemical reduction under visible light.

But de l’invention:

Proposer un nouveau catalyseur basique à base de Nickel, efficace dans le procédé du reformage sec du méthane par le CO2 qui permet: La réduction des émissions de deux gaz à effet de serre (CH4 et CO 2) en générant une grand activité catalytique. D obtenir des sélectivités plus importantes en gaz de synthèse (CO + H2) sans avoir à faire face au problème d empoisonnement crée par la dépôt de carbone sur la surface. Présentation de la substance de l invention: L invention en question est un matériau oxydes mixtes mésoporeux et multifonctionnel qui regroupe les propriétés acido-basiques et redox. Ce solide utilisé comme catalyseur dans la réaction de reformage sec de CH4 par CO2 sera obtenu par traitement thermique d un précurseur HDL à base de nickel et d aluminium dopé par un élément alcalino-terreux qui est le strontium (Sr) introduit dans l espace inter-feuillet via une nouvelle méthode de préparation, le HDL Ni/Al est préparé par la méthode coprécipitation directe à pH constant.

Résumé

Dans le cadre de ce travail, le polyacrylamide PAM a été utilisé comme matrice pour la synthèse d’hydrogels (nano) composites aux propriétés rhéologiques améliorées. Notre investigation de celles-ci a montré, à travers la mesure du module élastique G’, que la présence de 1% de la montmorillonite sodique MMT-Na dans le mélange réactionnel est suffisante pour induire une forte augmentation de la valeur du module élastique du réseau simple PAM. En outre, notre étude rhéologique a montré que le processus de gélification du mélange (acrylamide, initiateur et réticulant) n’est pas affecté par la présence de la MMT-Na. En nous basant sur la théorie de l’élasticité caoutchoutique, nous avons montré que le réseau (nano) composite PAM/MMT-Na possède une densité de jonctions effectives plus élevée que celle de son homologue simple PAM.

Résumé

Cette étude décrit l’élaboration d’un système de libération d’un principe actif, alliant les performances des hydrogels et de l’argile. Notre choix s’est porté sur les hydrogels du polyacrylamide et une argile locale la montmorillonite de Maghnia.  Afin de répondre à cet objectif, nous avons dans un premier temps organo-modifié la montmorillonite sodique puis synthétisé l’hydrogel simple polyacrylamide PAM et les hydrogels (nano)composites polyacrylamide-montmorillonite sodique PAM-NaMMT et polyacrylamide-montmorillonite organo-modifiée PAM-OMMT à 0,5 ; 1 et 3%  en chacune des deux argiles. L’insertion de ces dernières au sein du réseau polyacrylamide a été mise en évidence par spectroscopie Infrarouge à Transformée de Fourrier. Le comportement thermique de tous les réseaux sus-mentionnés a été examiné par analyse thermogravimétrique et analyse enthalpique différentielle. Dans un second temps, nous avons investigué le potentiel des hydrogels PAM, PAM-NaMMT et PAM-OMMT à piéger et à relarguer le chlorhydrate de metformine, pris comme molécule modèle. Le piégeage et le relargage de ce principe actif ont ét examine par spectroscopie ultraviolette en fonction de la nature de l’argile, de son taux d’insertion dans le réseau hôte PAM, et du milieu de relargage.

Abstract

In this study, as an alternative source of adsorbent for the removal of dyes from wastewaters, the leaves of Lamiacea specie which is a Medicinal and Aromatic Plant were used as an alternative and low cost biomaterial for feasibility study of Methyl Orange (MO) removal from wastewaters. Experiments were performed to investigate the impact of some parameters such as initial pH, temperature, dye initial concentration and adsorbent S/L ratio on the removal of MO. The results showed that an optimum of 70% of MO removal is reached at an ambient temperature T=25°C, for a biosorbent concentration of 13 to 16 (g/L) in acidic environments (pH=2). Kinetic experiments revealed that the adsorption of Methyl Orange onto the Lamiacea leaves can be described with pseudo second-order model and the equilibrium isotherm data were well described by the Langmuir I model. The maximum adsorption capacity of the biomass was found to be 70 mg/g at 25 °C. The proposed waste material collected from aromatic and flavors extraction industries may be proposed as suitable adsorbent for decolorization of industrial effluents due to its low cost; Thus, this preliminary study will be the base of future processes optimization and will be considered as model case studies for investigate other pollutants.