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Harmonic Distortion Rate Analysis of H-Bridges Multilevel Inverter

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材料科学与工程（中英文B版） 2011年第3期1卷 308-315页

作者： Mohamed Nejib ben nasr Khammassi Anis Kebir Faouzi ben Ammar Unite de recherche SICISI ESSTT 5av. Taha Hussein BP 56 Bab Mnara-1008 Universite de Tunis Tunisia Unite de recherche. LSE INSAT Centre Urbain Nord BP 676 1080 Tunisia

This paper represents comparative study on two control techniques applied to H-bridges multilevel inverter. The considered techniques are standard PWM and harmonic elimination control. Their performances are compared in terms of THD and commutation’s losses so that the choice of power switches is optimized. Simulation results indicated that the harmonic elimination technique exhibits better results than the standard PWM technique, which is sustained by the reduce of the commutation losses, and a power rise for the switches ensuring the use of GTOs, IGCTs.

关键词：多电平逆变器 H桥失真率 PWM技术谐波技术标准电源开关控制技术

Cascaded H-Bridges Asymmetrical 11-Levels Optimization

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材料科学与工程（中英文B版） 2011年第4期1卷 496-503页

作者： Mohamed Nejib ben nasr Khammassi Anis Kebir Faouzi ben Ammar Unite de Recherche SICISI ESSTT 5av. Taha Hussein BP 56 Bab Mnara-lO08 Universite de Tunis Tunisia Unitd de Recherche.＂ LSE INSA T Centre Urbain Nord BP 676 1080 Tunis

The following dissertation aims at investigating the multilevel topology basis through the analyses of the harmonic elimination control modeling methodology of the asymmetrical inverter. Thus the contribution of this paper can be summarized mainly by the fact that the pre-calculated PWM control used to control the symmetrical structure, as applied to the asymmetrical structure with a reduced number of cells, provides the same performance level resolution and signal strength to the load terminals, which guarantees a constant voltage frequency report. This observation is similar for the three cells, which allows the use of different drivers such as MOSFET, IGBT and GTO. These results have a good performance from the intrinsic proprieties of each semiconductor for each cell.

关键词：水平分辨率不对称非对称结构优化 H桥级联 MOSFET 消谐控制

Adsorption of rare earth elements onto diatomite M45:Experimental investigations and modeling with statistical physics theory

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Journal of Rare Earths 2023年第11期41卷 1805-1811,I0006页

作者： Fatma Dhaouadi Guilherme L.Dotto Julien Vieillard Diana Pinto Luis F.O.Silva Éder C.Lima Mu Naushad Fatma Aouaini Samia nasr Adrián Bonilla-Petriciolet Abdelmottaleb ben Lamine Laboratory of Quantum and Statistical Physics LR18ES18Faculty of Sciences of MonastirMonastir UniversityMonastirTunisia Research Group on Adsorptive and Catalytic Process Engineering(ENGEPAC) Federal University of Santa MariaAv.Roraima1000-797105–900Santa MariaRSBrazil NormandieUniversité UNIROUENINSA RouenCNRSCOBRA(UMR 6014)27000EvreuxFrance Universidad De La Costa Calle 58#55-66080002BarranquillaAtlánticoColombia Advanced Materials Research Chair Department of ChemistryCollege of ScienceKing Saud UniversityRiyadh11451Saudi Arabia Department of Chemistry College of ScienceBuilding#5King Saud UniversityRiyadhSaudi Arabia Department of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityAbha61413P.O.Box 9004Saudi Arabia Chemistry Department Faculty of ScienceKing Khalid UniversityP.O.Box 9004Abha61413Saudi Arabia Instituto Tecnológico de Aguascalientes 20256AguascalientesMexico

The separation of rare earth elements using diatomite M45 from aqueous solutions was *** experimental isotherms for the adsorption of trivalent lanthanum,cerium,and neodymium cations on this adsorbent were quantified under strongly acidic conditions(pH 2)at 298-328 *** adsorption equilibria of these earth elements were analyzed using two statistical physics models(homogeneous and heterogeneous monolayer models).The results show that the adsorption of these ions implies a multiionic mechanism,which is ***-containing functional groups are responsible for the adsorption of these rare-earth elements on the diatomite surface.A heterogeneous statistical physics model confirms that two Si-based functional groups participate in the separation of these *** calculated adsorption capacities at saturation follow the order:neodymium>cerium>*** interaction energies range from 28600 to 40100 J/mol,indicating physical adsorption on diatomite *** study demonstrates that diatomite M45 is a promising separation medium that can be used for the recovery of REEs dissolved in aqueous solutions via adsorption.

关键词： Lanthanum Cerium Neodymium Adsorption Diatomite M45 Statistical physics model

An unusual cause of optic neuritis:rickettsiosis disease

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Asian Pacific Journal of Tropical Biomedicine 2014年第12期4卷 998-1000页

作者： Loukil Hanen Snoussi Mouna Frikha Faten ben Salah Raida Jallouli Moez cherif Yosra EI Aoud Sahar Marzouk Sameh Bahloul Zouhir Department of Internal Medicine Hedi Chaker University Hospital

Optic neuritis(ON) may be associated to a range of autoimmune or infectious *** report herein a case of ON induced by Rickettsia conorii.A 53-year-old woman presented with a recent decrease in visual acuity and *** was diagnosed on the basis of ophthalmologic examination and flash visual evoked *** investigation made in our department eliminated first autoimmune disorders(vasculitis and connective tissue diseases).Rickettsial optic neuritis was confirmed by detection of specific antibodies in serum and the negativity of other serologic *** association between corticosteroids and cyclines was prescribed with improvement of visual acuity.

关键词： Optic neuritis Rickettsia conorii Mediterranean spotted fever Ocular involvement

In Front of Bilateral Pseudo Tumoral Ovarian Mass: Think about Tuberculosis

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Open Journal of Internal Medicine 2016年第2期6卷 27-30页

作者： Kechaou Ines cherif Eya Boukhris Imen Azzabi Samira ben Hassine Lamia Department B of Internal Medicine Charles Nicolle Hospital Tunis Tunisia

Ovarian and peritoneal localizations of tuberculosis are rare. They raise the problem of differential diagnosis with malignancy. In this regard, we reported the case of a 25-year-old woman who presented with bilateral pseudo tumoral ovarian mass mimicking an advanced ovarian carcinoma with ascites. Extemporaneous examination of the peritoneum confirmed the diagnosis of tuberculosis and avoided bilateral annexectomy that could compromise the fertility of the patient.

关键词： Ovarian Tuberculosis Ovarian Carcinoma CA 125 Fertility

Hydrogen recovery from big-scale porous metal hydride(MH)reactor:impact of pressure and MH-thermophysical properties

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Energy Storage and Saving 2022年第4期1卷 259-271页

作者： Atef Chibani Slimane Merouani Aissa Dehane cherif Bougriou Laboratory of Environmental Process Engineering Department of Chemical EngineeringUniversity Salah Boubanider Constantine 3ConstantineP.O.Box 72Algeria Department of Mechanical Engineering University of Mostefa Ben BoulaidBatna 2Batna05000Algeria Department of Process Engineering Faculty of Sciences and Applied SciencesLarbi Ben M’hidi University04000Oum El BouaghiAlgeria

An advanced ANSYS FLUENT-based model was developed for hydrogen recovery from a multi-tubular fixed-bed metal hydride(MH)reactor of large-scale *** model was firstly validated by comparing its results to specific experimental *** and heat transfer processes inside the fixed bed were investigated for various pressures and thermochemical characteristics of the MH(thermal conductivity,porosity and reaction parameters).The findings were reported as average,local and spatial changes in the metal’s bed temperature and hydrogen *** the initial stage of the endothermic desorption(t<100 s),the bed temperature dropped dramat-ically in all *** this time,there was a massive emission of *** bed temperature was then raised due to the reactor’s external convective heating,while the hydrogen release continued until the MH was completely *** dehydrogenation rate of the MH was enhanced when the discharge pressure was ***,some other characteristics of the MH,i.e.,porosity,thermal conductivity,desorption rate constant and activation energy,significantly impacted the resulting mass and heat fluxes inside the bed material.

关键词： Hydrogen storage Metal hydride(MH) Desorption Heat and mass transfer Mathematical model

Superselective embolisation of bilateral superior vesical arteries for management of intractable hematuria in context of metastatic bladder cancer

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Asian Journal of Urology 2017年第2期4卷 131-134页

作者： Ahmed Saadi Abderrazak Bouzouita Mohamed Hedi Rebai Mohamed cherif Walid Kerkeni Haroun Ayed Amine Derouiche Hatem Rajhi Riadh ben Slama Najla Mnif Mohamed Chebil Department of Urology Charles Nicolle University HospitalTunisTunisia Department of Radiology Charles Nicolle University HospitalTunisTunisia

Hematuria due to locally advanced or metastatic bladder cancer is a common condition and is often a management *** embolisation is a mini-invasive option to handle this *** report a case of a patient with a metastatic bladder cancer and who presented with an abundant hematuria and severe *** failure of endoscopic resections and“flush”of radiotherapy haemostatic and refusal of cystectomy by the patient,he was treated by superselective embolisation of bilateral superior bladder arteries with excellent immediate *** technique is safe and effective in the short *** longterm effectiveness requires further investigation.

关键词： Urinary bladder neoplasms Hematuria Therapeutic embolisation

Analytical Study of a Heat Recovery/Desiccant Cooling System under Tunisian Climatic Conditions

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Analytical Study of a Heat Recovery/Desiccant Cooling System...

Melting/solidification of phase change material in a multi-tube heat exchanger in the presence of metal foam:effect of the geometrical configuration of tubes

作者： Seifennasr Sabek Kaouther ben nasr Ridha Chouikh Amenallah Guizani the Centre des Recherches et des Technologies de l’Energie (CRTEn) the Ecole Nationale d’Architecture et d’Urbanisme the Institut Supérieur de Mathématiques Appliquées et d’ Informatique (ISMAI)

The solar potential energy in Tunisia can be used like a principal factor for the operation of new technologies of air *** could be carried out like approaches of simulation,analyzes experimental or both *** this paper,we present an analytical solution of heat and mass transfer processes in regenerator and air conditioning system(ACS) cores of a heat recovery/desiccant cooling system(HRDCS) under Tunisia weather *** programs were carried out to test the principal components of the HRDC *** results show that the coefficient of performance of system improves when we use the renewable energy for heating and *** study is significant and effective to prove the efficiency of such HRDC systems in this country.

关键词： Air conditioning liquid desiccant cooling system simulations Tunisian climatic conditions

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Energy Storage and Saving 2022年第4期1卷 241-258页

作者： Atef Chibani Aissa Dehane Slimane Merouani cherif Bougriou Djemaa Guerraiche Laboratory of Environmental Process Engineering Department of Chemical EngineeringFaculty of Process EngineeringUniversity Salah Boubnider Constantine 3Constantine25000Algeria Department of Mechanical Engineering Faculty of TechnologyUniversity of Mostefa Ben BoulaidBatna 2Batna05000Algeria Faculty of Sciences and Applied Sciences Department of Process EngineeringLarbi Ben M’hidi UniversityOum El Bouaghi04000Algeria Applied Energy Physics Laboratory(LPEA) Physical DepartmentFaculty of Matter SciencesUniversity of Batna 1Batna05000Algeria

One of the likely methods for enhancing heat transfer in a latent thermal energy storage system is the conception of a thermal *** this study,the orientation of oval tubes(horizontal,vertical,and oblique)in phase change material(PCM,C_(19)-C_(20))-based shell-tube heat exchanger was analyzed with respect to the metal foam(MF)type(graphite,copper,and nickel)in comparison to the case of pure *** this purpose,a two-dimensional mathematical model was developed to investigate the thermal efficiency of the PCM-metal foam based composite energy storage *** was concluded that the orientation of the oval tubes(oblique,horizontal,and vertical)has a negligible impact on the performance of the thermal unit during the melting/solidification *** on the liquid/solid fraction,total enthalpy and the average temperature in the annular space,the performance of a heat exchanger during fusion/solidification periods is in the order:copper-MF>graphite-MF>nickel-MF>pure *** the adopted MF or the geometry of tubes,the melting process is expedited compared to the solidification mechanism.

关键词： Phase change material(PCM) Solidification process Melting process PCM-metal foam Heat exchanger