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Characterisation of sediments polluted by acid mine drainage in the northeast of Algeria

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International Journal of Sediment Research 2012年第3期27卷 402-407页

作者： chahrazed BOUKHALFA Mounia CHAGUER Laboratory of pollution and water treatment Chemistry DepartmentUniversity Mentouri Constantine

The present study investigates the composition and the mineralogy of sediments in the Essouk River, located in the Northeast of Algeria in Sidi Kamber mining zone at approximately 2km upstream Guenitra *** mine is abandoned since 1976,but acidic drainage water is still a source of river *** X-Ray diffraction(XRD),scanning electron microscopy(SEM) with energy dispersive analyses(EDX),X -Fluorescence analyses and infrared spectroscopy analyses were used to characterize surface sediments sampled at various sites in the area near the mining effluents. The obtained results show that the composition of the sediments is mainly dominated by iron and *** the vicinity of the mine,jarosite and schwertmannite are the essential precipitates. Downstream,sediments are formed by various phases of iron oxyhydroxydes with the presence of adsorbed sulphate.

关键词： Acid mine drainage Sediments pollution Sediments analyses Iron oxyhydroxydes

Characterization of phosphorus interaction with sediments affected by acid mine drainage-relation with the sediment composition

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International Journal of Sediment Research 2017年第4期32卷 481-486页

作者： Lamia Boukemara chahrazed Boukhalfa Sarah Azzouz Laurence Reinert Laurent Duclaux Abdeltif Amrane Anthony Szymczyk Laboratory of Pollution and Water Treatment Chemistry Department University Mentouri Laboratory of Molecular Chemistry and Environment Universiry Savoie Mont Blanc Ecole Nationale Supérieure de Chimie de Rennes Université Rennes1CNRS

Phosphorus sorption capacity was investigated in surface sediments derived from an abandoned zinclead mine area located in northeastern Algeria. The forms and the distribution of phosphorus in the raw sediment were identified using the sequential chemical extractions method. Batch experiments were done to study the adsorption kinetics and isotherms. The pH effect was evaluated by macroscopic and infrared analyses. In raw sediment, speciation results show that phosphorus is dominantly bound to oxyhydroxides. Sorption experiments demonstrate that phosphorus uptake is principally related to sediment composition. The nature of the dominant iron oxyhydroxide has a substantial role in the adsorption capacity and the mechanism interaction. The adsorption kinetics can be described by the second order and Elovich models. The isotherms data are successfully modeled by the Temkin *** maximum phosphorus removal is reached under acidic pH. Spectroscopic analyses reveal that the predominance of jarosite implies electrostatic interaction with sediment particles. However, in the case of schwertmannite predominance, phosphate ions are adsorbed by the ligand exchange mechanism.

关键词： Phosphorus Adsorption Mine sediments Sorption kinetics Sorption isotherm

Synthesis,microstructure and dielectric properties of Sb-doped multiferroic Bi_(0.8)Ba_(0.2)Fe_(1-x)Sb_(x)O_(3)ceramics

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Journal of Advanced Dielectrics 2019年第4期9卷 30-37页

作者： Doreir Benzebeiri chahrazed Benhamideche Youghourta Belhocine Abdelghani May Salah-Eddine Bouaoud Cherif Benachour Unit of Environmental Chemistry and Molecular Structural Research(URCHEMS)University of Constantine 1 P.O.Box 325 Ain El Bey Road Constantine 25017Algeria Matter Science Department Faculty of Sciences 20 August 1955 University of Skikda P.O.Box 26 El Hadaik Road21000 SkikdaAlgeria Department of Petrochemical and Process Engineering 20 August 1955 University of Skikda P.O.Box 26 El Hadaik Road21000 SkikdaAlgeria Research Center in Industrial Technologies(CRTI)P.O.Box 64 Cheraga 16014AlgiersAlgeria

The multiferroic ceramics Bi_(0.8)Ba_(0.2)Fe_(1-x)Sb_(x)O_(3)with x=0,0.01,and 0.02 were synthesized using the solid-phase reaction *** samples were sintered at two different temperatures,850℃and 900℃.Scanning electron microscopy revealed the effect of antimony concentration on grain size and *** effect of Sb-doping on the crystal structure and ferroelectric properties of these ceramics was investigated using X-ray diffraction,Raman spectroscopy,and dielectric *** dielectric constant was enhanced upon Fe^(3+)substitution by Sb^(3+)without affecting the dielectric loss of the *** tetragonal distortion of the rhombohedral symmetry of BiFeO_(3)caused by Ba-doping at Bi 3þsite was lifted by Sb-doping at Fe^(3+)site.

关键词： Multiferroic ceramics solid phase reaction X-ray diffraction scanning electron microscopy dielectric properties

Stability of a Delayed SIQRS Model with Temporary Immunity

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Advances in Pure Mathematics 2013年第2期3卷 240-245页

作者： Laid chahrazed Rahmani Fouad Lazhar Department of Mathematics Faculty of Exact Sciences University Constantine 1 Algeria

This paper addresses a time-delayed SIQRS model with a linear incidence rate. Immunity gained by experiencing the disease is temporary;whenever infected, the disease individuals will return to the susceptible class after a fixed period of time. First, the local and global stabilities of the infection-free equilibrium are analyzed, respectively. Second, the endemic equilibrium is formulated in terms of the incidence rate, and locally asymptotic stability. Finally we use the adomian decomposition method is applied to the system epidemiologic. This method yields an analytical solution in terms of convergent infinite power series.

关键词： Adomian Method Epidemiology Mathematical Model The Epidemic Model The Equilibrium Points

Predicting an Optimal Virtual Data Model for Uniform Access to Large Heterogeneous Data

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Data Intelligence 2024年第2期6卷 504-530页

作者： chahrazed B.Bachir Belmehdi Abderrahmane Khiat Nabil Keskes LabRI-SBA Enterprise Information SystemsESI-SBA InstituteFraunhofer IAISAlgeriaGermany

The growth of generated data in the industry requires new efficient big data integration approaches for uniform data access by end-users to perform better business *** virtualization systems,including Ontology-Based Data Access(ODBA)query data on-the-fly against the original data sources without any prior data *** approaches by design use a fixed model e.g.,TABULAR as the only Virtual Data Model-a uniform schema built on-the-fly to load,transform,and join relevant *** other data models,such as GRAPH or DOCUMENT,are more flexible and,thus,can be more suitable for some common types of queries,such as join or nested *** queries are hard to predict because they depend on many criteria,such as query plan,data model,data size,and *** address the problem of selecting the optimal virtual data model for queries on large datasets,we present a new approach that(1)builds on the principal of OBDA to query and join large heterogeneous data in a distributed manner and(2)calls a deep learning method to predict the optimal virtual data model using features extracted from SPARQL ***-implementation of our approach currently leverages state-of-the-art Big Data technologies,Apache-Spark and Graphx,and implements two virtual data models,GRAPH and TABULAR,and supports out-of-the-box five data sources models:property graph,document-based,e.g.,wide-columnar,relational,and tabular,stored in Neo4j,MongoDB,Cassandra,MySQL,and CSV *** experiments show that our approach is returning the optimal virtual model with an accuracy of 0.831,thus,a reduction in query execution time of over 40%for the tabular model selection and over 30%for the graph model selection.

关键词： Data Virtualization Big Data OBDA Deep Learning

Analytical Model for GaAs MESFET with High Pinchoff Voltage

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材料科学与工程（中英文A版） 2013年第12期3卷 853-858页

作者： chahrazed Kaddour Cherifa Azizi Saade Edine Khemissi Mourad Zaabat Yasemina Saidi Faculty of Exact Sciences Larbi Ben M'hidi University Oum El Bouaghi 04200 Algeria

GaAs MESFET gallium arsenide metal semiconductor field effect transistor play an important role in high speed electronic circuits because of their higher velocity and mobility characteristics. For that, we propose in this communication a static model for the transistor in thin layers on base of gallium arsenide. This model describes the characteristics current-voltages which are connected to the various physical and electric parameters of material. It is valid for the components which have the high pinchoff-voltage (Vp > 3 V). The theoretical results obtained were compared with those of the experiment.

关键词： MESFET器件夹断电压 GaAs 金属半导体场效应晶体管解析模型移动特性电子电路静态模型

FTIR Analysis and Rheological Behavior of Bisphenol： A Diglycidyl Ether Resin Filled Fume-Silica

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材料科学与工程（中英文A版） 2014年第11期4卷 340-347页

作者： Irekti Amar Bezzazi Boudjema Boualam chahrazed Aribi Chouiab Dilmi Hamid Research Unit: Materials Processes and Environment University M'Hamed Bougara Boumerdes 35000 Algeria

Silica-fume as fillers into polymers materials affect significantly the physical, mechanical and the electrical properties of the polymers. The polymer that we studied here is an epoxy based resin (STR) and silica fume (FS). This paper presents the dependency of the rheological behavior of the STR epoxy resin on the FS content within a temperature at which the reaction thermoset is neglected. We used a cone-plate viscometer for the study of the rheological behavior, and a scanning electron microscope is used for the analysis of the dispersion state of the FS in STR epoxy resin. Compared to the control without loads, an increase of 50% of the shear stress and the plastic viscosity were recorded for the composite. The software Rheowine viscometer enabled us to model and identified the rheological behavior of these mixtures with resin. The results obtained in this modeling, confirmed that the resin mixtures have shear-thinning rheological behavior, this last give us the model of Ostwald de Waele.

关键词：环氧树脂流变行为二氧化硅二缩水甘油醚 FTIR分析聚合物材料扫描电子显微镜油烟

Obstetric recto-vaginal fistula: What technique to use?

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Open Journal of Obstetrics and Gynecology 2013年第5期3卷 441-444页

作者： Sanaa Errarhay Samia Mahmoud Najia Hmidani Hanane Saadi chahrazed Bouchikhi Abdelaziz Banani Department of Gynecology and Obstetrics CHU Hassan II Fez Morroco

Objective: The recto-vaginal fistula is an abnormal communication between the previous wall of the rectum and the posterior face of the vagina through the recto-vaginal septum. They are often due to the obstetric traumas and they can be of post-surgical origin. Methods: We report five cases of patients with obstetric recto-vaginal fistula and all of the patients have surgical intervention with a resection of the fistulous route and rectal wall. Results: The patient did not present any recidivating and the evolution is satisfactory without complications or recidivating. Conclusion: The treatment of recto-vaginal fistula is often difficult exposed to recurrence;and the therapeutic indications must be adapted to every type of fistula by taking into account its size, its location and its etiology.

关键词： Recto-Vaginal Obstetric Trauma Pelvic Trauma Treatment

Ovarian desmoplastic small round cell tumors: Prognosis is poor! Case report

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Open Journal of Obstetrics and Gynecology 2013年第2期3卷 235-238页

作者： Hanane Saadi Hind Fatmi Nissrine Mamouni Sanaa Errarhay chahrazed Bouchikhi Afaf Amarti Abdelaziz Banani Department of Gynecology Obstetrics I University Hospital Hassan II Fez Morocco Department of Pathology University Hospital Hassan II Fez Morocco

The tumor desmoplastic small round cell in women is rare. Ovarian its location is exceptional. We report a patient of 20 years, the originalNorth Africawho consulted for an increase in abdominal volume with impaired general condition. Pelvic ultrasonography and computed tomography were in favor of multiple peritoneal masses with ascites. After surgical exploration, the histological and immunohistochemical data for diagnosis small round cell desmoplastic tumor of ovarian the patient was a candidate for poly chemotherapy but she was died a month later. Diagnosis relies on histological and immunohistochemical data. The demonstration of a nonrandom translocation t (11;22) (p13;q12) is specific for the disease. The management is multidisciplinary and combining surgery, a poly aggressive chemotherapy and radiotherapy. The prognosis remains poor.

关键词： Small Round Cell Desmoplastic Tumor Ovarian Diagnosis Treatment Prognosis