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Characterization of Scale Formed in Drinking Water and Hot Water Pipes in the Taliouine Downtown—morocco

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American Journal of Analytical Chemistry 2015年第8期6卷 677-686页

作者： Naima Hafid m’barek belaatar Said Ben-Aazza Abdellah Hadfi mohamed Ezahri Ali Driouiche Engineering Process Laboratory Department of chemistry Faculty of Sciences Ibn Zohr University Agadir Morocco materials and Environment Laboratory Department of chemistry Faculty of Sciences Ibn Zohr University Agadir Morocco

This paper presents the results of a comprehensive study of water scale found in water distribution system of Taliouine city in the south of morocco. Physico-chemical properties of drinking water supplied to the city were evaluated. The data showed a high level of soluble salt in water. Concentrations were calcium 108 - 143 mg/1, magnesium 80 - 96 mg/1, bicarbonate 660 - 750 mg/l and hardness degree 660 - 690 mg CaCO3/l. The water samples contain high amounts of minerals in the form of ions, especially the metals calcium and bicarbonate, which precipitated out and caused problems in water conducting or storing vessels like pipes. Scales were removed from the inside of two old pipes which transported drinking and hot water in the downtown of Taliouine city. Scale samples were investigated by XRF, XRD, SEm, DTA, TGA and SEm’s analytical techniques. This study was able to identify scales formed in pipes of water distribution systems. It was found that water scale in this city contains 53% of calcium oxide and 43% of organic matter. The XRD and SEm results revealed that calcite was the main crystalline structure in drinking water scale. Nevertheless, scale deposited in hot water pipe is well crystalline with peaks corresponding mostly to aragonite (88%) along with calcite (12%). The thermal behavior of scale samples confirms that calcium carbonate was the main compound in the scale samples. Further studies are needed to find an efficient antiscale in drinking water of this city.

关键词： Drinking Water Scale Characterization Calcium Carbonate

Study of the Inhibitor Scaling Effect of the Agricultural Water by a Phosphate Fertilizer

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matched Asymptotic Expansions of the Eigenvalues of a 3-D Boundary-Value Problem Relative to Two Cavities Linked by a Hole of Small Size

Journal of Water Resource and Protection（水资源与保护） 2015年第15期

作者： Abdallah Hadfi Said Ben-Aazza m’barek belaatar Naima Hafid Ali Driouiche

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Communications in Computational Physics 2012年第2期11卷 456-471页

作者： Abderrahmane Bendali m’barek Fares Abdelkader Tizaoui Sebastien Tordeux Electromagnetism and Acoustics CERFACS42 Avenue Gaspard CoriolisF-31100 ToulouseFrance Toulouse University INSA-ToulouseMathematical Institute of ToulouseUMR-CNRS 5219135 avenue de RangueilF-31077 ToulouseFrance Laboratoire de mathematiques et de leurs Applications UMR-CNRS 5142Universite de Pau et des Pays de l’AdourF-64013 PauFrance Project Team mAGIQUE-3D INRIA Bordeaux-Sud-OuestF-64013 PauFrance

In this article,we consider a domain consisting of two cavities linked by a hole of small *** derive a numerical method to compute an approximation of the eigenvalues of an elliptic operator without refining in the ne... 详细信息

关键词： Elliptic operator matched asymptotic expansions eigenvalue problem finite elements

Use of human pluripotent stem cells to study and treat retinopathies

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World Journal of Stem Cells 2015年第3期7卷 596-604页

作者： Karim Ben m'barek Florian Regent Christelle monville INSERm UmR861 I-Stem AFM Genopole Campus 1 91030Evry France UEVE UmR861 I-Stem AFM Genopole Campus 1 91030 Evry France

Human cell types affected by retinal diseases(such as age-related macular degeneration or retinitis pimentosa) are limited in cell number and of reduced accessibility. As a consequence, their isolation for in vitro studies of disease mechanisms or for drug screening efforts is fastidious. Human pluripotent stem cells(h PSCs), either of embryonic origin or through reprogramming of adult somatic cells,represent a new promising way to generate models of human retinopathies, explore the physiopathological mechanisms and develop novel therapeutic strategies. Disease-specific human embryonic stem cells were the first source of material to be used to study certain disease states. The recent demonstration that human somatic cells, such as fibroblasts or blood cells, can be genetically converted to induce pluripotent stem cells together with the continuous improvement of methods to differentiate these cells into disease-affected cellular subtypes opens new perspectives to model and understand a large number of human pathologies, including retinopathies. This review focuses on the added value of h PSCs for the disease modeling of human retinopathies and the study of their molecular pathological mechanisms. We also discuss the recent use of these cells for establishing the validation studies for therapeutic intervention and for the screening of large compound libraries to identify candidate drugs.

关键词： Drug screening Human pluripotent stemcells Disease modeling Retinitis pigmentosa

International Financial market＇s Integration and modelling Returns of Risky Assets

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Journal of modern Accounting and Auditing 2012年第7期8卷 1042-1051页

作者： Ben m'barek Hassene University of Tunis Tunis Tunisia

The aim of this paper is to test the ability of conditional and unconditional capital asset pricing models （CAPms） and to explain emerging markets returns in terms of their integration into the international market. The authors use data on five developed countries and five emerging countries as well as data on the Tunis Stock Exchange （TSE） after the reforms. The results show that the correlations between emerging markets returns and developed markets returns are very low and sometimes negative. Conditional arbitrage pricing theory （APT） as well as conditional CAPm has low predictive power for emerging markets than that for developed markets. Finally, following the financial reforms, Tunisian financial markets have became more and more integrated into the international market （excess returns and unconditional beta consistent with predictions）. However, conditional APT does not accurately explain Tunisian market returns. This study confirms the unavailability of an accurate modelling technique of the TSE structure.

关键词： conditional unconditional capital asset pricing model (CAPm) conditional arbitrage pricing theory(APT) returns

Enhanced dielectric and electrocaloric properties in lead-free rod-like BCZT ceramics

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Journal of Advanced Ceramics 2020年第2期9卷 210-219页

作者： Zouhair HANANI Soukaina mERSELmIZ Abdelaadim DANINE Nicolas STEIN Daoud mEZZANE m’barek AmJOUD mohammed LAHCINI Yaovi GAGOU matjaz SPREITZER Damjan VENGUST Zdravko KUTNJAK mimoun El mARSSI Igor ALUK'YANCHUK mohamed GOUNE ImED-Lab Cadi Ayyad UniversityMarrakesh 40000Morocco ICmCB University of 1.BordeauxPessac 33600France IJL University of LorraineNancy 54000France Um6P Ben Guerir 43150Morocco LPmC University of Picardy Jules VerneAmiens 80039France Jozef Stefan Institute Ljubljana 1000Slovenia Physics Faculty Southern Federal UniversityRostov-on-Don 344090Russia

Ba0.85Ca0.15Zr0.10Ti0.90O3(BCZT)lead-free ceramics demonstrated excellent dielectric,ferroelectric,and piezoelectric properties at the morphotropic phase boundary(mPB).So far,to study the effect of morphological changes on dielectric and ferroelectric properties in lead-free BCZT ceramics,researchers have mostly focused on the influence of spherical grain shape *** this study,BCZT ceramics with rod-like grains and aspect ratio of about 10 were synthesized by surfactant-assisted solvothermal route.X-ray diffraction(XRD)and selected area electron diffraction(SAED)performed at room temperature confirm the crystallization of pure perovskite with tetragonal *** electron microscopy(SEm)image showed that BCZT ceramics have kept the 1D rod-like grains with an average aspect ratio of about ***-like BCZT ceramics exhibit enhanced dielectric ferroelectric(εr=11,906,tanδ=0.014,Pr=6.01μC/cm^2,and Ec=2.46 kV/cm),and electrocaloric properties(ΔT=0.492 K andz=0.289(K×mm)/kV at 17 kV/cm)with respect to spherical BCZT ***,rod-like BCZT lead-free ceramics have good potential to be used in solid-state refrigeration technology.

关键词： lead-free Ba0.85Ca0.15Zr0.10Ti0.90O3(BCZT) rod-like Ba0.85Ca0.15Zr0.10Ti0.90O3(BCZT) dielectric ferroelectric electrocaloric effect

Contribution of Risk Perception for the Analysis of Non-Compliance to Work Procedures

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Health 2014年第19期6卷 2705-2711页

作者： mohammed mouda mébarek Djebabra makhlouf Chati LRPI Laboratory of Institute of Health and Safety University of Batna Batna Algeria HSE Department of Regional Direction of Hassi R’mel Group of Sonatrach Laghouat Algeria

One of the problems encountered in work security is non-compliance to work procedures by operators. The consequences of such human behavior are harmful to both the operators and the organization. These consequences are the result of a situational behavior of operators. This article focuses on the perception of work situations in a sample of Algerian workers in oil companies knowing that this perception determines, in large part, the decisions taken by the operators in terms of non-compliance with work procedures.

关键词： Work Procedure Non-Compliance Human Behavior Human Perception

Novel lead-free BCZT-based ceramic with thermally-stable recovered energy density and increased energy storage efficiency

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Journal of materiomics 2022年第4期8卷 873-881页

作者： Zouhair Hanani Soukaina merselmiz m'barek Amjoud Daoud mezzane mohammed Lahcini Jaafar Ghanbaja matjaz Spreitzer Damjan Vengust mimoun El marssi Igor A.Luk'yanchuk Zdravko Kutnjak Brigita Rozic mohamed Goune ImED-Lab Cadi Ayyad UniversityAvenue Abdelkrim El KhattabiP.B.549Marrakesh40000Morocco ICmCB University of Bordeaux87 Avenue Du Dr Albert SchweitzerPessac33600France Jozef Stefan Institute Jamova Cesta 39Ljubljana1000Slovenia LPmC University of Picardy Jules Verne33 Rue Saint LeuAmiens80039France mohammed VI Polytechnic University Lot 660-Hay Moulay RachidBen Guerir43150Morocco IJL University of Lorraine54000NancyFrance Department of Building materials Kyiv National University of Construction and ArchitectureKyiv03680Ukraine

The eco-responsible lead-free piezoelectric ceramics have been intensively searched for more than adecade, however, the final goal to replace toxic ceramics like lead zirconate titanate (PZT) with lead-freecompounds, having comparable or even better performance has not yet been reached. In this road, thelead-free ceramics Ba_(0.85)Ca_(0.15)Zr_(0.1)Ti_(0.9)O_(3) (BCZT), possessing excellent dielectric, ferroelectric, andpiezoelectric properties are regarded as serious candidates for the PZT replacement. Besides, nano-structuring BCZT is of paramount importance to enhance these functionalities even more. Here, BCZTmultipodes are designed by template-growth hydrothermal synthesis using hydrogen zirconate titanatenanowires. We demonstrate that the fabricated BCZT multipodes exhibit high dielectric permittivity of5300 with a temperature stability coefficient of ±5.9% between 20 and 140℃. A significant recoveredenergy density of 315.0 mJ/cm^(3) with high thermal stability and high energy storage efficiency of 87.4%,and enhanced large-signal piezoelectric coefficient d^(*)_(33) (310 pm/V) are found. Compared to the tradi-tional BCZT ceramics reported in the literature, relying on high-temperature processing, our sampleexhibits boosted energy storage parameters at a much lower temperature. These outcomes may offer anew strategy to tailor eco-responsible relaxor ferroelectrics toward superior energy storage performancefor ceramic capacitor applications.

关键词： Lead-free ceramics Low temperature Piezoelectric Thermal stability Energy storage Nanostructuration

Geotechnical Study of the Aptian Limestone of the Kef Region,Northwestern Tunisia:Evaluation for Industrial Use

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Open Journal of Geology 2018年第12期8卷 1084-1101页

作者： Imed Ben Salah moufida Ben m’barek Jemai Safa mezza mabrouk Boughdiri Department of Geology Sciences University of BizerteUniversity of CarthageBizerteTunisia

This study aims to the initial characterization of Aptian sedimentary limestones in the Kef region located in the North-West of Tunisia in order to use in industrial fields. The limestone samples were collected from three outcrops respectively named Jebel Jerissa, Jebel Hmeima and Jebel Harraba. A geochemical characterization highlights a variation of the weight percentage (wt%) as follows: CaO (53 - 55), mgO (0.04 - 0.28), Al2O3 (0.07 - 0.51), Fe2O3 (0.41 - 2.87), and a loss on ignition (41.62 - 43.35). The other oxides (K2O, SO3, Na2O) are in trace amounts. mineralogical analysis revealed that limestones contain more than 95% of calcite and the clay impurities are the minor phases detected. Petrographic study showed that these limestones are packestone-wakestone type. The hardness of Aptian limestones crosses the upper limit of the hard domain. Geotechnical tests reveal a Dry micro Deval (mDS) coefficient varying from 23% to 33%, a Wet micro Deval (mDH) coefficient with values oscillating around 26% to 36%, a Los Angeles coefficient (LA) about 25% against a value of the compressive strength ranging from 593 Kg/cm2 to 866 Kg/cm2. The gravimetric tests highlighted a flexural strength value from 106 Kg/cm2 at 208 Kg/cm2, while the ultrasonic coefficient oscillates from 4876 m/s to 5233 m/s, indicating the low porosity of these limestone (0.5% to 1%). The density recorded an average value of 2.50 g/cm3. The various properties studied have proved that the limestone studied can be used in various industrial fields such steel industry, aggregate, cement industry and marble.

关键词： Aptian Limestone Geotechnical Properties Geochemical Properties Industrial Use