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Chemical Durability, Structure Properties and Bioactivity of Glasses 48P2O5-30CaO-(22−x)Na2O-xTiO2(With 0 <x ≤ 3;mol%)

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Advances in Materials Physics and Chemistry 2020年第12期10卷 305-318页

作者： Yassine Er-Rouissi Sara Aqdim abdeslam el bouari Fouzia Hmimid Said Aqdim Faculty of Sciences Laboratory of Materials Engineering for Environment and Valorization Hassan II University Ain Chock Casablanca Morocco Faculty of Sciences Ben-M’sik Laboratory Physical-Chemistry of Applied Materials Hassan II University Casablanca Morocco Department of Biology Faculty of Science Laboratory Health & Environment Hassan II University Ain Chock Casablanca Morocco Department of Chemistry Faculty of Science Mineral Chemistry Laboratory Hassan II University Ain Chock Casablanca Morocco

Phosphate glasses of composition 48P2O5-30CaO-(22−x)Na2O-xTiO2 (with 0 °C ± 20°C. The chemical durability of these glasses shows an improvement when the TiO2 content varies from 0 to 2 mol%. The measurements of dif... 详细信息

Phosphate glasses of composition 48P2O5-30CaO-(22−x)Na2O-xTiO2 (with 0 elting at 1080°C ± 20°C. The chemical durability of these glasses shows an improvement when the TiO2 content varies from 0 to 2 mol%. The measurements of differential thermal analysis and density, both, indicate the increase of the glass transition temperature and the density. The increase of Tg leads to an improvement of glass rigidity. X-ray diffraction analysis of the glasses annealed at 650°C for 48 h, indicates the appearance of a mixture of metaphosphate and pyrophosphate phases when the TiO2 content varies from 0 to 2 mol%, the last become majority when the TiO2 content rich 2 mol%. Nevertheless, when the TiO2 content exceeds 2 mol%, the analysis, both, by infrared spectroscopy and X-ray diffraction, reveals a radical change of structure with the formation of majorities isolated orthophosphate groups. SEM micrographs illustrated that the number of crystallites increased in the glass network when the TiO2 content increased at the expense of the Na2

关键词： Chemical Durability Phosphate Glasses Titan Oxide Bioactivity SBF

Structural Features and Properties of the Vitreous Part of the System 50P2O5-25CaO-(25-x)Na2O-xCoO (with 0 ≤ x ≤ 25;mol%)

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Advances in Materials Physics and Chemistry 2021年第12期11卷 254-266页

作者： Brahim Bachachir Yassine Er-Rouissi Radouane Makhlouk Achraf Harrati abdeslam el bouari Said Aqdim Faculty of Sciences Ain Chock Laboratory of Materials Engineering for Environment and Valorization Hassan II University Casa-blanca Morocco Faculty of Sciences Ben-M’sik Laboratory Physical-Chemistry of Applied Materials Hassan II University Casablanca Morocco Department of Chemistry Faculty of Science Mineral Chemistry Laboratory Hassan II University Ain Chock Casablanca Morocco

The glass series 50P2O5-25CaO-(25-x)Na2O-xCoO (with (0 ≤ x ≤ 25;mol%), has been prepared by direct melting at 1080°C ± 20°C. The introduction of cobalt in calcium phosphate glasses is used to compare its effect with calcium in inhibition corrosion. The dissolution rate has been investigated. It indicated an improvement of chemical durability when the cobalt oxide increases in the network glass at the expense of Na2O content. Both, IR spectroscopy and X-ray diffraction have confirmed the structure changes when the CoO content increases in the glass. This change results in the disappeara

关键词： Chemical Durability Phosphate Glasses Cobalt Oxide Density DTA DRX IR SEM Micrograph

Effects of Lizardite Addition on Technological Properties of Forsterite- monticellite Rich Ceramics Prepared from Natural Magnesite and Dolomite

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Journal of Construction Research 2020年第1期2卷 9-20页

作者： Ahmed Manni Achraf Harrati Abdelilah el Haddar Abdelwahed Chari Ali Sdiri Fahd Oudrhiri Hassani abdeslam el bouari Iz-Eddine el Amrani el Hassani Chaouki Sadik Laboratory of Physical Chemistry of Applied Materials(LPCMA) Department of ChemistryFaculty of Sciences Ben MsikHassan II University of CasablancaMorocco Laboratory of Applied Geosciences Faculty of SciencesUniversity of Mohammed 1OujdaMorocco Materials Sciences Energy and Nano-engineering DepartmentMohammed VI Polytechnic UniversityBen GuerirMorocco Department of Georessources and Environment National Engineering SchoolUniversity of SfaxP.Box 3052SfaxTunisia LMPEQ University of Cadi AyyadENSA of SAFIMorocco Geomaterials and Geo environment Team/Geo-Biodiversity and Natural Patrimony Laboratory (GEOBIO)/GeophysicsNatural Patrimony and Green Chemistry Research Centre(GEOPAC)Scientific InstitutMohammed V University of RabatMorocco

Lizardite rich peridotite has never been used to prepare ceramic specimens,especially in *** this raison,potential use of naturally abundant lizarditic material from the Rif domain,as a supply for ceramic industry,has been *** effects of lizardite addition to magnesite and dolomite mixtures on the thermomechanical properties of the calcined ceramics were also *** achieve this target,natural lizardite,magnesite and dolomite samples were collected in ultrabasic Beni Bousra *** raw samples were used for the synthesis of a forsterite-monticellite rich *** raw and sintered samples were characterized by x-ray diffraction,scanning electron microscope and fourier transform *** obtained results showed that both magnesite and dolomite were mainly composed of MgCO_(3) and CaCO_(3).In contrast,lizardite sample showed high amounts of SiO_(2),MgO and Fe2O_(3).An increased amount of lizardite in the initial mixtures enhanced mechanical and dimensional properties of the prepared ceramic specimens,and subsequently,the production of ceramics with the required technological ***,the preparation of Moroccan lizardite-based ceramics is technically feasible,economically justifiable and socially desirable due to the contribution to the economic growth of the raw materials sector,especially ceramic industry.

关键词： Forsterite Monticellite Lizardite Basic ceramics Temperature

Geothermobarometry of Askaoun Pluton in Ouzellarh-Sirwa Promontory (Central Anti-Atlas;Morocco)

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Open Journal of Geology 2012年第3期2卷 136-147页

作者： abdeslam Toummite Moha Ikenne el Hassane Beraaouz Applied Geology and Environmental Geology Laboratory Faculty of Sciences Ibn Zohr University Agadir Morocco

Rocks of the late Neoproterozoic Askaoun pluton (558 ± 2 Ma) located in the Ouzellarh-Sirwa promontory (Anti-Atlas) include magmatic microgranular enclaves (MMEs) ranging from rounded to ovoid in shape, dark and fine grained and generally 5 to 10 cm in size, some reaching a size of 50 cm. They are composed of microdiorite, quartz microdiorite and micromonzodiorite, whereas the felsic host rocks comprise mainly quartz-diorite and amphibole-biotite granodiorite based on mineralogical compositions. The mineral assemblage is similar to those described in their hosting granitoids but with different proportions. In this study composition of minerals is used to describe the nature of the magma and estimate the pressure, temperature and oxygen fugacity at which Askaoun pluton is emplaced. Based on chemistry of biotite Askaoun pluton formed from calc-alkaline magma. Compositions of plagioclase (An5 - An29);hornblende (Mg ≠= 0.59 - 0.65) and biotite (Mg ≠= 0.49 - 0.55) of MMEs are slightly distinct or similar to those of host rocks (An7-40;hbl Mg ≠= 0.64 - 0.69;Bi Mg ≠= 0.49 - 0.50) which suggest partial to complete equilibration during mafic-felsic magma interaction. The coexisting hornblende and plagioclase (hornblende-plagioclase thermometry), Al content in hornblende (aluminum-in-hornblende barometry) and the assemblage titanite-magnetite-quartz were used to constrain the P, T and fO2 during the crystallization of the parent magmas. The Askaoun pluton was emplaced at temperature ca. 504°C - 633°C and at pressure ca. 0.9 - 4.66 ± 0.6 Kbars (average depth = 6.5 km) from a highly oxidized magma (log fO2 = ?24.8 to ?19.2).

关键词： Askaoun Pluton MMEs Hornblende Thermobarometry Ouzellargh-Sirwa Promontory Anti-Atlas Morocco

A Finite element Approximation of the Stokes Equations

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World Journal of Mechanics 2011年第6期1卷 299-305页

作者： Samy Alami abdeslam elakkad Jawad el-Mekaoui Ahmed elkhalfi Mohammed el Hammoumi 不详

In this work, a numerical solution of the incompressible Stokes equations is proposed. The method suggested is based on an algorithm of discretization by the unstable of Q1 – P0 velocity/pressure ?nite element approximation. It is shown that the inf-sup stability constant is O(h) in two dimensions and O( h2) in three dimensions. The basic tool in the analysis is the method of modi?ed equations which is applied to ?nite difference representations of the underlying ?nite element equations. In order to evaluate the performance of the method, the numerical results are compared with some previously published works or with others coming from commercial code like Adina system.

关键词： Stokes Equations Finite element Method Iterative Solvers Adina System

Geochemical assessment, mixing behavior and environmental impact of thermal waters in the Guelma geothermal system,Algeria

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Acta Geochimica 2019年第5期38卷 683-702页

作者： Foued Bouaicha Henia Dib Oualid Bouteraa Nabil Manchar Kamel Boufaa Nabil Chabour abdeslam Demdoum Department of Applied Biology Universite des Freres Mentouri Constantine 1025000 ConstantineAlgeria Department of Geology Universite des Freres Mentouri Constantine 1025000 ConstantineAlgeria Laboratory of Geology and Environment (LGE) Uni versite des Freres Mentouri Constantine 1ConstantineAlgeria Department of Geology Sciences University of Larbi Ben M'hidi04000 Oum El BouaghiAlgeria Department of Earth Sciences University of Setif 119000 SetifAlgeria

A study of thirteen geothermal springs located in the geothermal field of Guelma,northeastern Algeria,was *** were collected during the period between January 2014 and February *** processes responsible for the chemical composition of thermal and mineralized water were *** hydrochemical analysis shows that the thermal waters are characterized by the presence of two different chemical facies,the first type SO4-Ca in the east,west and south of Guelma,the second type HCO3-Ca in the *** analysis also attributed to sodium,chlorides,and sulfates to an evaporitic terrigenous origin by the molar ratio Sr2+/Ca2+.The thermal spring waters from Guelma geothermal system have a meteoric origin,and all samples are immature with strong mixing between hot and shallow waters with 19-38.5%rate of *** silica geothermometer shows that these thermal waters have a temperature varying from 84 to 122℃and that the water came from a depth of 2100-3000 m through a fault system that limits the pullapart basin of *** environmental effluent from thermal spas could pollute in both the irrigation and drinking waters,and which imposes danger on the health of the inhabitants of the region.

关键词： Geochemistry Geothermometry Mixing Thermal effluents Guelma Algeria

A Novel Decoder Based on Parallel Genetic Algorithms for Linear Block Codes

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International Journal of Communications, Network and System Sciences 2013年第1期6卷 66-76页

作者： abdeslam Ahmadi Faissal el Bouanani Hussain Ben-Azza Youssef Benghabrit Department of Communication Networks National High School of Comptuer Science and System Analysis Rabat Morocco Department of Industrial and Production Engineering Moulay Ismail University National High School of Arts and Trades Meknès Morocco

Genetic algorithms offer very good performances for solving large optimization problems, especially in the domain of error-correcting codes. However, they have a major drawback related to the time complexity and memory occupation when running on a uniprocessor computer. This paper proposes a parallel decoder for linear block codes, using parallel genetic algorithms (PGA). The good performance and time complexity are confirmed by theoretical study and by simulations on BCH(63,30,14) codes over both AWGN and flat Rayleigh fading channels. The simulation results show that the coding gain between parallel and single genetic algorithm is about 0.7 dB at BER = 10﹣5 with only 4 processors.

关键词： Channel Coding Linear Block Codes Meta-Heuristics Parallel Genetic Algorithms Parallel Decoding Algorithms Time Complexity Flat Fading Channel AWGN

Towards an UML Profile for Web Service Composition Based on Behavioral Descriptions

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Journal of Software Engineering and Applications 2012年第9期5卷 711-721页

作者： Ayoub Sabraoui Ahmed Ettalbi Mohammed el Koutbi abdeslam En-Nouaary electrical and Computer Engineering Department Concordia University Montreal Canada Mobile Intelligent Systems Team (MIS) Ecole Nationale Supérieure d’Informatique et d’Nalyse des Systèmes (ENSIAS) Rabat Mo-rocco

Web service composition is one of the challenging issues that have been investigated over the past decade. It consists of combining and reusing existing Web services to best suit new user requirements. This paper proposes an UML profile to compose Web services based on their behavioral aspects. To do so, the web service WSDL files are first transformed to UML models;then the profile is used to integrate them;finally the MDA approach is adopted to transform the applied profile into a BPel process. As such, our method has the advantages of being independent of the Web service composition language and the UML modeling tool. Finally, a case study is developed in order to show the benefits of our method.

关键词： Web Service Composition UML Profile MDA BPel

Study of Initial Adhesion of a Bacterium to Different Support Materials before and after Conditioning Film of Olive Oil-Mill Wastewater

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Advances in Bioscience and Biotechnology 2020年第8期11卷 391-404页

作者： Taoufik Hakim Souad Lekchiri Hassan Latrache Mohamed el Amine Afilal abdeslam Jaafari Safae Tankiouine Mostafa ellouali Hafida Zahir Bioprocess and Biointerfaces Laboratory Faculty of Sciences and Techniques Sultan Moulay Slimane University Beni Mellal Morocco Biochemistry and Biotechnology Laboratory Mohamed First University Oujda Morocco

To improve the start-up speed and efficiency of bioreactors, biofilm technology is sometimes used. This technology uses various types of materials to facilitate the adhesion of microorganisms. In this study, the surface characteristics of inert substrates and substrates after olive oil-mill wastewater (OMWW) conditioning film were evaluated to understand the impact of OMWW on adhesion as well as the most suitable material to optimize bacterial adhesion. Three common substrates made of different polymers were tested for bacterial adhesion before and after treatment with OMWW: PP (polypropylene), PET (Polyethylene terephthalate), and PVC (polyvinyl chloride). The surfaces’ physicochemical characteristics were studied by measuring the contact angle for the studied bacteria strain and the supports, before and after treatment with OMWW. Results of initial adhesion tests for untreated and treated supports showed differences in how bacterial cells adhered to substrates. Before treatment with OMWW, PVC and then PP showed a significant adhesion capacity, double that of PET [PVC: 1.58 × 105 CFU/cm2, PP: 1.48 × 105 CFU/cm2 and PET: 0.72