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Structure, Thermal Behavior and Characterization of a New Hybrid Iron Fluoride FeF4（2,2′-bipyridine）（H2O）2

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Chemical Research in Chinese Universities 2015年第1期31卷 16-20页

作者： Mouna SMIDA Hager LITAIEM mohamed dammak Santiago GARCIA-GRANDA Laboratoire de Chimie Inorganique Faculte des Sciences de Sfax Universite de Sfax 3000Sfax Tunisie Departement de Chimie Physique Analytique Faculte de Chimie Universite d'Oviedo-CINN 33006 Oviedo Spain

New crystal of FeF4（2,2′-bipyridine）（H2O）2 was prepared by hydrothermal synthesis. Crystalline structure determination is performed from single crystal X-ray diffraction data. The unit cell is monoclinic space group P21/n, with cell parameters a=0.9046（5） nm, b=0.7502（5） nm, c=1.9539（5） nm,β=93.307（5）°, V=1.3238（12） nm^3 and Z=4. The structure of FeF4（2,2＇-bipyridine）（H2O）2 is built up from FeF4N2 octahedra coordinated by two nitrogen atoms of the 2,2＇-bipyridine molecules, and four fluorine atoms as well as uncoordinated H2O molecules. Thermal analysis of the title compound showed that the decomposition introduced four steps. IR spectra confirmed the presence of 2,2＇-bipyridine molecules. The optical absorption was measured at the corresponding 2max using UV-Vis diffuse reflectance spectrum.

关键词： Hydrothermal synthesis Hybrid Iron fluoride

Synthesis, Structural Study and Phase Transitions Characterization by Thermal Analysis and Vibrational Spectroscopy of an Ammonium Rubidium Arsenate Tellurate

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Chemical Research in Chinese Universities 2016年第6期32卷 902-911页

作者： GHORBEL Khouloud LITAIEM Hajer KTARI Lilia GARCIA-GRANDA Santiago dammak mohamed Laboratoire de Chimie Inorganique(LCI) Universitd de Sfax Facultd des Sciences de Sfax BP 1171 Sfax 3000 Tunisia Laboratoire de Chimie Physique et Analytique Faeulte de Chimie Universitte d 'Oviedo Oviedo 33006 Espagne

The Rb2.42（NH4）0.58（HAsO4）（H2AsO4）. Te（OH）6 crystals（denoted by RbNAsTe） crystallize in the monoc-linic system, space group P21/n with the following parameters： a=1.3059（5） nm, b=0.6755（3） nm, c=1.6675（6） rim,β=94.126（4）°, Z=4 and V=1.46733（10） nm^3. Thermal analyses（DSC, DTA and TG） confirm the presence of the phasetransition and the temperatttre of the decomposition. The vibrational spectroscopy study at room temperature showthe presence and the independence of anionic groups, cationic groups, and give more importance to the hydrogenbonds. Raman spectra were recorded in the temperature range of 298--503 K. The temperature dependence of theRaman line shift, intensity reduction and the half width detects the phase transitions and confirms their nature. So, thephase transition at 453 K corresponds to the superprotonic-ionic conduction phase transition, and those at 483 and491 K correspond to the decomposition of our material.

关键词： RbNAsTe X-Ray diffraction Differential scanning calorimetry Phase transition Raman spectrometry

Structural studies and conductivity of [Fe(O3C4)(COO)]·H2O based H4btec (H4btec = 1,2,4,5-benzenetetracarboxylic acid)

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Open Journal of Inorganic Chemistry 2013年第4期3卷 100-108页

作者： Manel Halouani mohamed Abdelhedi mohamed dammak Nathalie Audebrand Lilia Ktari Laboratoire de Chimie Inorganique Faculté des Sciences de Sfax Université de Sfax Sfax Tunisia Laboratoire de Matériaux Inorganiques: Chimie Douce et Réactivité UMR 6226 Sciences Chimiques de Rennes Université Rennes 1 Rennes France

A new metal-organic hybrid compound?[Fe(O3C4)(COO)]·H2O I has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Rust crystals crystallize in the monoclinic system, space group I2/a, a = 6.9651(2) A, b = 8.12630(10) A, c = 19.4245(2) A, β = 92.6600(10)°;V = 1098.25(4) A3;Z = 2 and Dx =3.63g/cm3. The refinement converged into R = 0.042;Rw = 0.058. The structure, determined by single crystal X-ray diffraction, consists of a network of FeO6 centers, octahedral coordinated by btec (btec = 1,2,4,5-benzenetetracarboxylic acid) anions giving rise to a two-dimensional sheet structure. In the compound I,?[Fe(O3C4)(COO)]·H2O, the FeO6 group bridged by the 1,2,4,5-benzenetetracarboxyl anion exist in a unit cell, with each anion lying about an inversion centre. One of the FeO2 adistance [1.965(2)] significantly corresponds to the shortest distance as the other and the distances found in the axial direction of compound I.

关键词： Hydrothermal Synthesis X-Ray Diffraction Crystal Structure

Experimental and Numerical Analyses of the Pull-out Response of a Steel Post/Bovine Bone Cementless Fixation

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Journal of Bionic Engineering 2012年第4期9卷 501-507页

作者： Khaled Gammoudi mohamed Kharrat Maher dammak National Engineering School of Sfax Electromechanical Systems Laboratory Soukra road km 3.5 B.P. 1173 3038 Sfax Tunisia Higher Institute of Technological Studies of Gafsa University campus Sidi Ahmed Zarrouk 2112 Gafsa Tunisia Faculty of Sciences of Gafsa University campus Sidi Ahmed Zarrouk 2112 Gafsa Tunisia Preparatory Institute for Engineering Studies of Sfax Menzel Chaker Road Km 0.5 B.P. 1172 3018 Sfax Timisia

Effect of initial interference fit on pull-out strength in cementless fixation between bovine tibia and smooth stainless steel post was investigated in this study. Compressive behavior of bovine spongious bone was studied using mechanical testing in order to evaluate the elastic-plastic properties in different regions of the proximal tibia. Friction tests were carried out in the aim to evaluate the friction behavior of the contact between bovine spongious bone and stainless steel. A cylindrical stainless steel post inserted in a pre-drilled bovine tibia with an initial interference fit was taken as an in vitro model to assess the contribution of post fixation to the initial stability of the Total Knee Arthroplasty （TKA） tibial component. Pull-out experiments were carried out for different initial interference fits. Finite Element Models （FEM） using local elastic-plastic properties of the bovine bone were developed for the analysis of the experimental ultimate pull-out force results. At the post/bone interface, Coulomb friction was considered in the FEM calculations with pressure-dependent friction coefficient. It was found that the FEM results of the ultimate force are in good agreement with the experimental results. The analysis of the FEM interfacial stresses indicates that the micro-slip initiation depends on the local bone properties.

关键词： total knee arthroplasty bovine bone/steel post fixation interference fit puU-out strength FEM

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

Integrability of det▽u and Evolutionary Wente's Problem Associated to Heat Operator

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Chinese Annals of Mathematics,Series B 2007年第5期28卷 527-532页

作者： Sami BARAKET Makkia dammak mohamed JLELI Dong YE Departement de mathematiques Faculte des Sciences de Tunis Campus Universitaire2092 TunisTunisie. Departement de mathematiques Ecole Superieure des Sciences et Techniques de Tunis5 Avenue Taha-HusseinTunis BP 56Bab Menara 1008Tunisie. Departement de mathematiques UMR8088Universite de Cergy-Pontoise site Saint-Martin BP22295302 Cergy-Pontoise cedexFrance.

In this note,the authors resolve an evolutionary Wente's problem associated to heat equation,where the special integrability of det▽u for u∈H^1(R^2,R^2)is used.

关键词： Jacobian determinant Heat equation Wente's problem