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Effect of Replacing Vanadium by Niobium and Iron on the Tribological Behavior of HIPed Titanium Alloys

Acta Metallurgica Sinica(English Letters) 2017年第11期30卷 1089-1099页

作者： mamoun fellah Linda Aissani Mohammed Abdul Samad Alain Iosts Touhami Mohamed Zine Alex Montagnes Corinne Nouveau Mechanical Engineering Department ABBES Laghrour University P.O. 1252 40004 Khenchela Algeria Tribology Materials Surface and Interfaces GroupLaboratory of Foundry BADJI Mokhtar University BO 12CP 23000 Annaba Algeria Physics Department ABBES Laghrour University P.O.1252 40004 Khenchela Algeria Mechanical Engineering Department KFUPM Box 1180Dhahran 31261 Kingdom of Saudi Arabia Laboratory of Mechanics Surfaces and Processing Materials ARTS ET METIERS ParisTech Boulevard Louis XIV 859046 Lille Cedex France La.Bo.Ma.P ENSAM Rue Porte de Paris 71250 ClunyFrance

This study aims to examine the effect of replacing vanadium by niobium and iron on the tribological behavior of hot-isostatic-pressed titanium alloy （Ti-6Al-4V） biomaterial, using a ball-on-disk-type oscillating tribometer, under wet conditions using physiological solution in accordance with the ISO7148 standards. The tests were carried out under a normal load of 6 N, with an AISI 52100 grade steel ball as a counter face. The morphological changes and structural evolution of the nanoparticle powders using different milling times （2, 6, 12 and 18 h） were studied. The morphological characterization indicated that the particle and crystallite size continuously decrease with increasing milling time to reach the lowest value of 4 nm at 18-h milling. The friction coefficient and wear rate were lower in the samples milled at 18 h （0.226, 0.297 and 0.423; and 0.66 × 10-2, 0.87 × 10-2 and 1.51 × 10-2 μm3 N-1 i, tm-1） for Ti-6Al-4Fe, Ti-6A1-7Nb and Ti-6Al-4V, respectively. This improvement in friction and wear resistance is attributed to the grain refinement at 18-h milling. The Ti-6Al-4Fe samples showed good tribological performance for all milling times.

关键词： Tribological behavior Titanium alloys Wear testing Nanotribology Milling time Hot isostatic pressing(HIPing)

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Thin layers of Fe doped ZnO deposited by spin-coating for electrolysis and photodetector applications

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Transactions of Nonferrous Metals Society of China 2024年

作者： Dikra BOURAS mamoun fellah Regis BARILLE Amjad IQBAL Hamadi FOUZIA Obrosov ALEKSEI Gamal A.EL-HITI Faculty of Science and Technology， University of Souk-Ahras Mechanical Engineering Department， ABBES Laghrour University Biomaterial， Synthesis and Tribology Research team， ABBES Laghrour-University MOLTECH-Anjou， Université d'Angers/UMR CNRS 6200 Department of Materials Technologies， Faculty of Materials Engineering， Silesian University of Technology Matter science department， ABBES Laghrour University Brandenburg University of Technology Cottbus-Senftenberg Department of Optometry， College of Applied Medical Sciences， King Saud University

ZnO is nowadays not only used as an additive for the copper and cement industry， but also in medicine and cosmetic industry as part of the substitute materials of choice for the field of new technologies such as renewable energy. This study aims to investigate the effect of iron concentration on the microstructural and structural properties of ZnO for Electrolysis and Photodetector Applications. The Thin layers of un-doped and doped ZnO with different percentages of Fe （2， 4， and 6 wt.%） were deposited by spin-coating on glass substrates. Sample characterization was done by X-ray diffraction （XRD）， Atomic force microscopy （AFM）， Scanning electron microscopy （SEM）， energy-dispersive X-ray spectroscopy （EDS）， UV-visible absorption spectra and X-ray photoelectron spectroscopy （XPS）. Structural measurements by XRD show that all the layers are polycrystalline with a hexagonal Wurtzite structure. Two new peaks were also discovered after the doping process （400） and （440） belonging to the Fe2O4crystal phase spectrum. Morphological analysis showed that the surface roughness values of ZnO layers ranged between 8 and 45 nm. XPS studies confirmed the presence of Fe in +3 states in ZnO layers. An average transmittance of 90% was measured by UV- in the wavelength range of 200-900 nm. The values of the energy gap （Eg） decreased with an increase in the concentration of Fe. AFM topography results confirmed that ZnO-based thin layers have a relatively uniform surface. The efficiency of these samples has been confirmed for their use in many electrical applications， including photodetectors and electrolysis of contaminated solutions.

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Friction and Wear Behavior of Ti-6Al-7Nb Biomaterial Alloy

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Journal of Biomaterials and Nanobiotechnology 2013年第4期4卷 374-384页

作者： mamoun fellah Omar Assala Mohamed Labaiz Leila Dekhil Alain Iost Surface Engineering and Tribology Team Laboratory of Metallurgy and Engineering MaterialsBADJI Mokhtar-Annaba UniversityAnnabaAlgeria Laboratory of Formability and Metallic Materials BADJI Mokhtar-Annaba UniversityAnnabaAlgeria Laboratory of Metallurgy ARTS ET METIERS ParisTechLilleFrance

Titanium has been increasingly applied to biomedical application because of its improved mechanical characteristics, corrosion resistance and biocompatibility. However their application remains limited, due to the low strength and poor wear resistance of unalloyed titanium. The purpose of this study is to evaluate the friction and wear behavior of high-strength titanium alloys: Ti-6Al-7Nb used in femoral stem (total hip prosthesis). The oscillating friction and wear tests have been carried out in ambient air with oscillating tribotester in accord with standards ISO 7148, ASTM G99-95a, ASTM G 133-95 under different conditions of normal applied load (3, 6 and 10 N) and sliding speed (1, 15 and 25 mm.s-1), and as a counter pair we used the ball of 100C 6, 10 mm of diameter. The surface morphology of the titanium alloys has been characterized by SEM, EDAX, micro hardness, roughness analysis measurements. The behavior observed for both samples suggests that the wear and friction mechanism during the test is the same for Ti alloys, and to increase resistance to wear and friction of biomedical titanium alloys used in total hip prosthesis (femoral stems) the surface coating and treatment are required.

关键词： Tribological Behavior Friction and Wear Tests Biomaterial Total Hip Prosthesis Ti-6Al-7Nb

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Effect of sintering temperature on structure and tribological properties of nanostructured Ti-15Mo alloy for biomedical applications

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Transactions of Nonferrous Metals Society of China 2019年第11期29卷 2310-2320页

作者： mamoun fellah Naouel HEZIL Dekhil LEILA Mohammed ABDUL SAMAD Ridha DJELLABI Stephania KOSMAN Alex MONTAGNE Alain IOST Aleksei OBROSOV Sabine WEISS Mechanical Engineering Department ABBES Laghrour-UniversityKhenchelaP.O.125240004Algeria Tribology and Materials Group Laboratory of FoundryBadji Mokhtar UniversityAnnabaB.O.12 CP 23000Algeria Mater Sciences Department ABBES Laghrour-UniversityKhenchelaP.O.125240004Algeria Laboratoire de Mise en forme des Matériaux Métalliques(LMF2M) UniversitéBadji—MokhtarB.P.1223000 AnnabaAlgeria Mechanical Engineering Department King Fahd University of Petroleum and MineralsBox 1180Dhahran 31261KSA Department of Environmental Engineering College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518055China Arts et Metiers ParisTech MSMP8Boulevard Louis XIV59046 Lille CedexFrance Department of Physical Metallurgy and Materials Technology Brandenburg Technical University03046 CottbusGermany

The effect of sintering temperature(1073?1373 K)on the structural and tribological properties of nanostructured ballmilledβ-type Ti?15Mo samples was *** prepared samples were characterized using various apperatus such as X-ray diffractometer,scanning electron microscope(SEM)and ball-on-plate type oscillating *** tests were conducted under different applied loads(2,8 and 16 N).Structural results showed that the mean pore and crystallite size continuously decreased with increasing sintering temperature to reach the lowest values of 4 nm and 29 nm at 1373 K,*** relative density of the sintered sample at 1373 K was as high as 97.0%.Moreover,a higher sintering temperature resulted in higher relative density,greater hardness and elastic modulus of the *** was observed that both the friction coefficient and wear rate were lower in the sample sintered at 1373 K which was attributed to the closed porosity.

关键词： Ti-15Mo wear tribological behaviour nanotribology sintering biomedical applications

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Towards a simple and safe Objective Caml compiling framework for the synchronous language SIGNAL

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Frontiers of Computer Science 2019年第4期13卷 715-734页

作者： Zhibin YANG Jean-Paul BODEVEIX mamoun FILALI School of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 211106 China State Key Laboratory of Software Development Environment Beijing 100191 China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 211106 China IRIT-CNRS Universite de Toulouse Toulouse 31062 France

This paper presents a simple and safe compiler, called MinSIGNAL, from a subset of the synchronous dataflow language SIGNAL to C, as well as its existing en? hancements. The compiler follows a modular architecture, and can be seen as a sequence of source-to-source transformations applied to an intermediate representation which is named Synchronous Clocked Guarded Actions (S-CGA) and translation to sequential imperative code. Objective Caml (OCaml) is used for the implementation of MinSIGNAL. As a modem functional language, OCaml is adapted to symbolic computation and so, particularly suitable for compiler design and implementation of formal analysis tools. In particular, the safety of its type checking allows to skip some verification that would be mandatory with other languages. Additionally, this work is a basis for the formal verification of the compilation of SIGNAL with a theorem prover such as Coq.

关键词： synchronous languages SIGNAL Synchronous Clocked Guarded Actions (S-CGA) Objective Caml functional programming

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A comparative study of two formal semantics of the SIGNAL language

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Frontiers of Computer Science 2013年第5期7卷 673-693页

作者： Zhibin YANG Jean-Paul BODEVEIX mamoun FILALI School of Computer Science and Engineering Beihang University Beijing 100191 China IRIT-CNRS Universite de Toulouse Toulouse 31062 France

SIGNAL is a part of the synchronous languages family, which are broadly used in the design of safety-critical real-time systems such as avionics, space systems, and nu- clear power plants. There exist several semantics for SIG- NAL, such as denotational semantics based on traces （called trace semantics）, denotational semantics based on tags （called tagged model semantics）, operational semantics presented by structural style through an inductive definition of the set of possible transitions, operational semantics defined by syn- chronous transition systems （STS）, etc. However, there is lit- tle research about the equivalence between these semantics. In this work, we would like to prove the equivalence be- tween the trace semantics and the tagged model semantics, to get a determined and precise semantics of the SIGNAL language. These two semantics have several different defini- tions respectively, we select appropriate ones and mechanize them in the Coq platform, the Coq expressions of the abstract syntax of SIGNAL and the two semantics domains, i.e., the trace model and the tagged model, are also given. The dis- tance between these two semantics discourages a direct proof of equivalence. Instead, we transform them to an intermediate model, which mixes the features of both the trace semantics and the tagged model semantics. Finally, we get a determined and precise semantics of SIGNAL.

关键词： synchronous language SIGNAL trace seman- tics tagged model semantics semantics equivalence Coq

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DISSOLUTION KINETICS OF GOLD AND SILVER IN CYANIDATION

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Transactions of Nonferrous Metals Society of China 1992年第3期2卷 53-58页

作者： Fang Zhaoheng mamoun Muhammed Institute of Chemical Metallurgy Academia SinicaBeijing 100080China Royal Institute of Technology Sweden

The dissolution kinetics of gold and silver cyanidation of Cu-Au sulfide concentrate has been investigated at ambient temperature in consideration of effects of various parameters,such as particle size of ores,*** of the process and initial cyanide concentration as well as oxygen partial *** experimental data are mathematically treated with an approach based on the shrinking core model.A phenomenological expression describing the rate and rate constants for cyanidation of the concentrate is developed from the *** dissolution of gold and silver is explained by an electrochemical mechanism in which the rate determining step is,the diffusion of cyanide and dissolved molecular oxygen through a porous layer formed during the minerals dis-solutions.

关键词： dissolution kinetics Cu-Au sulfide concentrate cyanidation electrochemical mechanism

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SVM Model Selection Using PSO for Learning Handwritten Arabic Characters

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Computers, Materials & Continua 2019年第9期61卷 995-1008页

作者： mamouni El mamoun Zennaki Mahmoud Sadouni Kaddour Département Informatique Universitédes Sciences et de la Technologie d’Oran Mohamed Boudiaf USTO-MB BP 1505 El M’naoeur31000OranAlgérie

Using Support Vector Machine(SVM)requires the selection of several parameters such as multi-class strategy type(one-against-all or one-against-one),the regularization parameter C,kernel function and their *** choice of these parameters has a great influence on the performance of the final *** paper considers the grid search method and the particle swarm optimization(PSO)technique that have allowed to quickly select and scan a large space of SVM parameters.A comparative study of the SVM models is also presented to examine the convergence speed and the results of each *** is applied to handwritten Arabic characters learning,with a database containing 4840 Arabic characters in their different positions(isolated,beginning,middle and end).Some very promising results have been achieved.

关键词： SVM PSO handwritten Arabic grid search character recognition

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Structural damage assessment criteria for reinforced concrete buildings by using a Fuzzy Analytic Hierarchy process

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Underground Space 2018年第3期3卷 243-249页

作者： Khader M.Hamdia Mohammed Arafa mamoun Alqedra Institute of Structural Mechanics Bauhaus-Universitat Weimar99423 WeimarGermany Department of Civil Engineering The Islamic University of GazaGazaPalestine

Reinforced concrete structures are often exposed to many types of damages and deteriorations due to different causes and exposure conditions during their life *** of such structures is inherently subjected to uncertainty and ambiguity,where subjective opinion and incomplete numeric data are *** the damage assessment process,estimating the importance of assessment criteria is an important field in itself,and depends heavily on the experience and expertise of *** aim of this study is to present a fuzzy-based assessment model,which estimates the importance of structural assessment criteria for concrete *** work aims also at studying,identifying,and prioritizing assessment *** assessment criteria are based on close visual inspections and simple measurements that do not require special testing or long-term *** main assessment criteria include the state of building history,environmental conditions,structural capacity,durability,and professional involvement in *** of them has two levels of *** criteria weights are obtained based on the opinions of experts using the Fuzzy Analytic Hierarchy Process(FAHP)*** application of the FAHP method showed that the most important criteria is the structural capacity with a weighting factor of 50.1%,followed by the environmental condition as second,with a weighting factor of 22.5%.

关键词： Assessment criteria Uncertainty Fuzzy logic Analytic hierarchy process Building evaluation

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Smart contract token-based privacy-preserving access control system for industrial Internet of Things

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Digital Communications and Networks 2023年第2期9卷 337-346页

作者： Weizheng Wang Huakun Huang Zhimeng Yin Thippa Reddy Gadekallu mamoun Alazab Chunhua Su Department of Computer Science City University of Hong KongHong Kong SAR999077China Division of Computer Science University of AizuFukushima965-8580Japan School of Information Technology and Engineering Vellore Institute of TechnologyTamil NaduIndia College of Engineering IT and EnvironmentCharles Darwin UniversityAustralia School of Computer Science and Cyber Engineering Guangzhou UniversityChina

Due to mobile Internet technology's rapid popularization,the Industrial Internet of Things(IIoT)can be seen everywhere in our daily *** IIoT brings us much convenience,a series of security and scalability issues related to permission operations rise to the surface during device ***,at present,a reliable and dynamic access control management system for IIoT is in urgent *** till now,numerous access control architectures have been proposed for ***,owing to centralized models and heterogeneous devices,security and scalability requirements still cannot be *** this paper,we offer a smart contract token-based solution for decentralized access control in IIoT ***,there are three smart contracts in our system,including the Token Issue Contract(TIC),User Register Contract(URC),and Manage Contract(MC).These three contracts collaboratively supervise and manage various events in IIoT *** also utilize the lightweight and post-quantum encryption algorithm-Nth-degree Truncated Polynomial Ring Units(NTRU)to preserve user privacy during the registration ***,to evaluate our proposed architecture's performance,we build a prototype platform that connects to the local ***,experiment results show that our scheme has achieved secure and dynamic access control for the IIoT system compared with related research.

关键词： Blockchain Privacy preservation Smart contract Industrial IoT

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