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Exergo-Environmental Study of a Recent Organic Solar Hybrid Heat Pump

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Fluid Dynamics & Materials Processing 2023年第4期19卷 991-1001页

作者： Rabeb Toujani Nahla Bouaziz universitéde Tunis El Manar Ecole Nationale D’Ingénieurs de TunisUnitéde Recherche Energ tique et EnvironnementTunis1002Tunisie

A hybrid heat pump(compression/absorption)with an integrated thermal photovoltaic unit is *** considered working fluids are organic mixtures:R245fa/DMAC and R236fa/DMAC,chosen for their low Global Warming *** main objective is the optimization of energy efficiency in order to minimize the environmental impact through the implementation of a sustainable *** is shown that Exergy Analysis itself is a valuable tool in energy *** the imposed framework of minimizing total annual costs,entropy analysis can be instrumental in determining the optimal plant concept,optimizing energy conversion and use,and improving *** present results are discussed under the optimistic hope that they may help to define new energy and environmental policies.

关键词： Impact environmental exergy analysis CO_(2)emissions solar hybrid heat pump

Integration of automatic voltage regulator and power system stabilizer: small-signal stability in DFIG-based wind farms

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1115-1128页

作者： Sirine ESSALLAH Adel BOUALLEGUE Adel KHEDHER universite de Sousse Ecole Nationale d’Ingenieurs de SousseLATIS-Laboratory of Advanced Technology and Intelligent Systems4023 SousseTunisia

The increasing penetration of wind farms in the energy sector directly affects the dynamic behavior of the power *** increasing use of wind energy in the power system worsens its stability and inherently influences the firmness of a small *** investigate these effects,one of the synchronous generators(SGs)of the grid is considered defective and is replaced by a doubly fed induction generator(DFIG)-based wind farm of the same *** small-signal stability of a power system is usually evaluated via eigenvalue analysis where local-area and inter-area oscillatory modes for the New England test system are *** controls,such as automatic voltage regulator(AVR)and power system stabilizer(PSS),are added to attenuate the generated *** this study,the impact of wind energy on the small-signal stability of the power system is *** combinations of AVR and PSS types are considered to mitigate the undesirable alterations.A comparative study is performed based on numerical simulations to choose the best combination of AVR and PSS *** obtained results prove that the proposed combination yields good results in terms of stability enhancement both under normal operating conditions and in DFIG-based wind farms.

关键词： Power system stability Power transmission system Transient analysis Voltage regulation

Thermal Activation of Asymetrical Composites for Vibration Control

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Modern Mechanical Engineering 2013年第3期3卷 1-8页

作者： Axel Imbert Gildas L’Hostis David Rigel Rigel Fabrice Laurent Bernard Durand Centre Technique des Industrie Mécanique Centre Recherche Matériaux Textiles Mulhouse France fabrice.laurent@uha.fr Laboratoire de Physiques et Mécanique Ecole Nationale d’Ingénieur de Sud Alsace Mulhouse France Laboratoire de Physiques et Mécanique Ecole Nationale d’Ingénieur de Sud Alsace Mulhouse France Laboratoire de Physiques et Mécanique Ecole Nationale d’Ingénieur de Sud Alsace Mulhouse France Centre Technique des Industrie Mécanique Centre Recherche Matériaux Textiles Mulhouse France

The CBCM (Controlled Behaviour Composite Material) is a thermal active composite, which has been developed for morphing applications. The thermal activation is made by a source of heating generated within the composite structure. The coupling between the induced thermal field and the thermomechanical properties of the various components of the composite structure leads to the change of the structure shape. The heat source is generated by Joule effect, Carbon yarns inserted in the composite, are connected to a power supply. The application field of CBCM technology is the domain of shape modification and active assembly. The objective of this work is to illustrate the capabilities of CBCM in the domain of vibration control. We will study several reference plates with different constitution. The influences of these different constitutions, of the CBCM effect and the loss of stiffness for the matrix will be highlighted, for two boundary conditions, free/free and embedded/embedded.

关键词： Composite Material Vibration Control Smart Materials Active Structure

Mechanical Characterisation of Interface for Steel/Polymer Composite Using Pull-out Test: Shear-Lag and Frictional Analysis

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Journal of Materials Science & Technology 2006年第4期22卷 552-558页

作者： Mohamed KHARRAT Maher DAMMAK Amine CHARFI Institut Préparatoire aux Etudes d'Ingénieurs de Sfax Tunisia Laboratoire des Systèmes ElectromécaniquesEcole Nationale d'Ingénieurs de SfaxTunisia Laboratoire des Systèmes Electromécaniques Ecole Nationale d'Ingénieurs de SfaxTunisia

Fibre-matrix interface is known to have contribution to the mechanical performance of fibre-reinforced composite by its potential for load transfer between the fibre and the matrix. Such load transfer is of great importance in dentistry when a post is used for fixing a ceramic crown on the tooth. In this study, a pull-out test was carried out to analyse the interfacial properties of a steel fibre embedded in a polyester and epoxy matrices. It was found that the fibre-matrix interface is debonded on the whole embedded length when the fibre stress reached the debonding stress. Then, the fibre stress fell down to the initial extraction stress required to pulling out the debonded fibre from the matrix. Both debonding stress and initial extraction stress initiated a linear increase with the implantation length after the debonding stress reached horizontal asymptotes. To analyse the fibre-matrix load transfer before debonding, an analytical shear-lag model was adopted to in this test conditions. Fitting the experimental results with the analytical model provided the interfacial shear strength. By considering the Coulomb friction at the fibre-matrix interface during the fibre extraction process, an analytical model which considers Poisson＇s effects on both fibre and matrix, was developed. In this model, knowledge of the initial extraction stress of the fibre provides the residual normal stress at the fibre-matrix interface.

关键词： Fibre Matrix Interface Pull-out Shear-lag debonding Friction

3D random Voronoi grain-based models for simulation of brittle rock damage and fabric-guided micro-fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第6期6卷 506-521页

作者： E.Ghazvinian M.S.Diederichs R.Quey Geo Engineering Centre Queen's UniversityKingston ON Canada ecole nationale supérieure des Mines de Saint-Etienne CNRS UMR 5307 France

A grain-based distinct element model featuring three-dimensional （3D） Voronoi tessellations （randompoly-crystals） is proposed for simulation of crack damage development in brittle rocks. The grainboundaries in poly-crystal structure produced by Voronoi tessellations can represent flaws in intact rockand allow for numerical replication of crack damage progression through initiation and propagation ofmicro-fractures along grain boundaries. The Voronoi modelling scheme has been used widely in the pastfor brittle fracture simulation of rock materials. However the difficulty of generating 3D Voronoi modelshas limited its application to two-dimensional （2D） codes. The proposed approach is implemented inNeper, an open-source engine for generation of 3D Voronoi grains, to generate block geometry files thatcan be read directly into 3deC. A series of Unconfined Compressive Strength （UCS） tests are simulated in3deC to verify the proposed methodology for 3D simulation of brittle fractures and to investigate therelationship between each micro-parameter and the model＇s macro-response. The possibility of numericalreplication of the classical U-shape strength curve for anisotropic rocks is also investigated innumerical UCS tests by using complex-shaped （elongated） grains that are cemented to one another alongtheir adjoining sides. A micro-parameter calibration procedure is established for 3D Voronoi models foraccurate replication of the mechanical behaviour of isotropic and anisotropic （containing a fabric） rocks. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Numerical modelling 3D Voronoi tessellation Discrete element method Grain-based model Crack damage thresholds Fabric-guided micro-fracturing Anisotropy

Regional gradient observability for semilinear hyperbolic systems： HUM approach

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Control Theory and Technology 2018年第1期16卷 72-80页

作者： Adil KHAZARI Ali BOUTOULOUT Imad EL HARRAKI Sidi Mohamed Ben Abdellah university Ecole Nationale de Commerce et de gestion Fez Morocco TSI Team MACS Laboratory Faculty of Sciences Moulay Ismail University Meknes Morocco ecole nationale superieure des mines de Rabat Rabat Morocco

The paper aims to extend the notion of regional observability of the gradient to the semilinear hyperbolic case, in order to reconstruct the gradient of the initial conditions in a subregion w of the domain evolution Ω. We start with an asymptotically linear system, the approach is based on an extension of the Hilbert uniqueness method （HUM） and Schauder＇s fixed point theorem. The analysis leads to an algorithm which is successfully numerically implemented and illustrated with examples and simulations.

关键词： Distributed systems fixed point regional gradient observability regional reconstruction semilinear hyperbolic systems

Rare dentin defects:Understanding the pathophysiological mechanisms of COLXVA1 mutations

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Genes & Diseases 2024年第5期11卷 1-5页

作者： Isaac Maximiliano Bugueno Tristan Rey Alexandra Jimenez-Armijo Marzena Kawczynski Naji Kharouf Marie-Cecile Maniere Yann Herault Agnes Bloch-Zupan Virginie HaushalterLaugel Institute of Genetics and Molecular and Cellular Biology(IGBMC) CNRS-UMR7104INSERM U1258Universitede StrasbourgIllkirch 67400France Faculty of dentistry Universitede StrasbourgStrasbourg 67000France Institute of Advanced Studies(USIAS) Universitede StrasbourgStrasbourg 67045France Reference Center for Rare Oral and dental Diseases(CRMR-O-Rares) Oral Medicine and Surgery DepartmentHopitaux Universitaires de Strasbourg(HUS)Strasbourg 67000France Rare Diseases Health Network“TETE COU”&European Reference Network ERN CRANIO Strasbourg 67000France “Institut de Genetique Medicale d’alsace” Laboratory of Genetic DiagnosticHopitaux Universitaires de Strasbourg(HUS)Strasbourg 67000France Biomaterials and Bioengineering Laboratory Inserm UMR_S 1121Strasbourg 67000France Orofacial development and Regeneration Faculty of MedicineInstitute of Oral BiologyCentre of Dental MedicineUniversity of ZurichZurich 8032Switzerland

dentin is a mineralized tissue with a chemical composition similar to bone but with a higher mineralized density and *** constitutes the central structure of the tooth between the internal pulp and external enamel toward the oral cavity or cementum toward the underlying *** dentin defects occur in a variety of rare genetic *** can manifest as“isolated”occurrences such as in dentinogenesis imperfecta(DI)or dentin dysplasia(DD)or can be associated with other symptoms in diseases such as osteogenesis imperfecta,Goldblatt syndrome,microcephalic osteodysplastic primordial dwarfism type Ⅱ,among others.

关键词： diseases den rigidity

Nickel ferrite spinel as catalyst precursor in the dry reforming of methane:Synthesis,characterization and catalytic properties

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Journal of Natural Gas Chemistry 2012年第5期21卷 595-604页

作者： Rafik Benrabaa Hamza Boukhlouf Axel Lfberg Annick Rubbens Rose-Nelle Vannier Elisabeth Bordes-Richard Akila Barama Laboratoire de Matériaux Catalytiques & Catalyse en Chimie Organique Faculté de ChimieUSTHBBP32 El Alia16111 Bab EzzouarAlgerAlgérie Unité de Catalyse et de Chimie du Solide UMR CNRS 8181Ecole Nationale Supérieure de Chimie de LilleUniversitédes Sciences et Technologies de LilleCité Scientif ique59655 Villeneuve d'AscqFrance

Dry reforming of methane by CO2 using nickel ferrite as precursor of catalysts was *** ferrite crystalline particles were prepared by coprecipitation of nitrates with NaOH or ammonia followed by calcination,or by hydrothermal synthesis without calcination *** textural and structural properties were determined by a number of analysis methods,including X-ray diffraction （XRD）,Raman spectroscopy and X-ray photoelectron spectroscopy （XPS）,among which X-ray diffraction （XRD） was at room and variable *** synthesized oxides showed the presence of micro or nanoparticles of NiFe2O4 inverse spinel,but Fe2O3 （hematite） was also present when ammonia was used for *** reducibility by hydrogen was studied by temperature-programmed reduction （TPR） and in situ XRD,which showed the influence of the preparation *** surface area （BET）,particle size （Rietveld refinement）,as well as surface Ni/Fe atomic ratio （XPS） and the behavior upon reduction varied according to the synthesis *** catalytic reactivity was investigated using isopropanol decomposition to determine the acid/base *** catalytic performance of methane reforming with CO2 was measured with and without the pre-treatment of catalysts under H2 in 650-800 C *** catalytic conversions of methane and CO2 were quite low but they increased when the catalysts were pre-reduced.A significant contribution of reverse water gas shift reaction accounted for the low values of H2 /CO *** coking was observed as shown by the reoxidation step performed after the catalytic *** possible formation of nickel-iron alloy observed during the study of reducibility by hydrogen was invoked to account for the catalytic behavior.

关键词： dry reforming of methane NiFe2O4 spinel hydrothermal synthesis coprecipitation isopropanol decomposition

“BUTTERFLY” PRECIPITATES IN δ-TiN_(0.53)→δ’-TiN_(0.53) ORdeRING TRANSFORMATION①

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中国有色金属学会会刊：英文版 1996年第2期6卷 57-60页

作者： Du Jun Yang Gaiying Portier R Shi Likai (General Research Institute for Non-Ferrous Metals, Beijing 100088 ecole nationale superieure de Chimie de Paris, 75231 Paris, France) General Research Institute for Non-Ferrous Metals Beijing 100088 China ecole nationale superieure de Chimie de Paris 75231 Paris France

“ＢＵＴＴＥＲＦＬＹ”ＰＲＥＣＩＰＩＴＡＴＥＳＩＮδ－ＴｉＮ_（０．５３）→δ’－ＴｉＮ_（０．５３）ＯＲＤＥＲＩＮＧＴＲＡＮＳＦＯＲＭＡＴＩＯＮＤｕＪｕｎ；ＹａｎｇＧａｉｙｉｎｇ；ＰｏｒｔｉｅｒＲ；ＳｈｉＬｉｋａｉ（... 详细信息

“ＢＵＴＴＥＲＦＬＹ”ＰＲＥＣＩＰＩＴＡＴＥＳＩＮδ－ＴｉＮ_（０．５３）→δ’－ＴｉＮ_（０．５３）ＯＲＤＥＲＩＮＧＴＲＡＮＳＦＯＲＭＡＴＩＯＮＤｕＪｕｎ；ＹａｎｇＧａｉｙｉｎｇ；ＰｏｒｔｉｅｒＲ；ＳｈｉＬｉｋａｉ（ＧｅｎｅｒａｌＲｅｓｅａｒｃｈＩｎ...

关键词： butterfly”precipitates δ’-TiN0.53 ordering transformation