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Protic ionic liquids/poly(vinylidene fluoride) composite membranes for fuel cell application

Journal of energy Chemistry 2021年第2期30卷 197-207,I0008页

作者： Isabel Vazquez-Fernandez Mohamed Raghibi Adnane Bouzina Laure Timperman Janick Bigarre Meriem Anouti laboratoire km2e Parc de GrandmontUniversite de Tours37200ToursFrance CeA-DAM Le Ripault BP16F-37260MontsFrance

Poly(vinylidene fluoride), PVDF, membranes have attracted considerable attention as polymer electrolytes for fuel cells. This study explores the effect of solvent on the spherulite size and the crystallinity of the polymeric membranes. Based on Hansen solubility parameters theory, the mixture of DMC and DMSO was selected among a dozen of solvents for the preparation of PVDF membranes by thermally induced phase separation. The addition of two protic ionic liquids(PILs), bis(2-ethyl hexyl) ammonium hydrogen phosphate [eHNH_2][H_2PO_4], and imidazolium hexanoate [Im][Hex] to PVDF membranes at concentrations(10% een investigated by SeM, FTIR, DSC, TGA, eIS, and DMA. The inclusion of ionic liquids into the polymer matrix influences structural parameters(degree of crystallinity and electroactive phases), thermal stability, proton conductivity and mechanical properties of the membranes. The membranes become transparent regardless type of ionic liquid employed. A small amount of ionic liquids increases the degree of crystallinity and facilitates the production of polar β and γ crystals. The proton conductivity mechanism(Grotthuss) is dependent on the ionic liquid structure(due to its selforganization in water) and the content in the PVDF membrane, as well as the membrane water *** behavior has been observed for the two ionic liquids, which stresses the challenge on selecting an appropriate cation and anion combination. The obtained composite membranes exhibited excellent mechanical performance and reduced elastic modulus, with respect to the pure polymer matrix. These results indicate that PVDF/IL composite membranes have a high potential for PeMFC applications.

关键词： PVDF Hansen solubility parameters PILs Proton conductivity

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An investigation of merging and diverging cars on a multi-lane road using a cellular automation model

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Chinese Physics B 2012年第11期21卷 565-572页

作者： K.Jetto H.ez-Zahraouy A.Benyoussef laboratoire de Magnétisme et de la Physique des Hautes energies Universit'e Mohammed V Faculté des Sciences ecole Hassania des Travaux Publics km 7 Route DEL JADIDAB.P 8108OasisCasablancaMaroc

In this paper, we have investigated two observed situations in a multi-lane road. The first one concerns a fast merging vehicle. The second situation is related to the case of a fast vehicle leaving the fastest lane back into the slowest lane and targeting a specific way out. We are interested in the relaxation time T, i.e., which is the time that the merging （diverging） vehicle spends before reaching the desired lane. Using analytical treatment and numerical simulations for the NaSch model, we have found two states, namely, the free state in which the merging （diverging） vehicle reaches the desired lane, and the trapped state in which T diverges. We have established phase diagrams for several values of the braking probability. In the second situation, we have shown that diverging from the fast lane targeting a specific way out is not a simple task. even if the diverging vehicle is in the free phase, two different states can be distinguished. One is the critical state, in which the diverging car can probably reach the desired way out. The other is the safe state, in which the diverging car can surely reach the desired way out. In order to be in the safe state, we have found that the driver of the diverging car must know the critical distance （below which the way out will be out of his reach） in each lane. Furthermore, this critical distance depends on the density of cars, and it follows an exponential law.

关键词： traffic flow merging and diverging area intelligent transportation system cellular au-tomation

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Analysis of the Biotribological Behavior for the Stainless Steel/Polyethylene Contact Using a Knee Prosthesis Simulator

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Journal of Bionic engineering 2012年第1期9卷 59-65页

作者： M. Boujelbene S. Dhouibi M. Kharrat M. Dammak laboratoire des Systkmes electromeeaniques Ecole Nationale d＇Ingenieurs de Sfax Route de Soukra km 35 B.P. 1173 3038 Sfax Tunisia Institut Superieur de Gestion Industrielle de Sfax Route de Mharza Km 15 B.P. 954 3018 Sfax Tunisia Faeulte des Sciences de Gafsa Campus Universitaire Sidi Ahmed Zarrouk 2112 Gafsa Tunisia Institut Preparatoire aux etudes d＇Ingenieurs de Sfax Route de Menzel Chaker Km 05 B.P. 1172 3018 Sfax Tunisia

In this work, a friction and wear simulator was used to reproduce the Anterior-Posterior （AP） sliding and the Flex- ion-extension （Fe） rotation generated in the knee joint during human gait cycle. We chose to simplify the contact geometry between the Total Knee Arthroplasty （TKA） femoral component and tibial insert. A 304L stainless steel cylinder which replaces the femoral component was loaded onto a flat High Density Polyethylene （HDPe） block which replaces the tibial insert. The tribological behavior of the considered contact was analyzed by tracking the number of cycles, the friction coefficient, the roughness of the wear track on HDPe, the HDPe weight loss and the damage mechanisms. The friction coefficient shows a gradual increase with the number of cycles for both AP and Fe kinematics. The evolution of friction coefficient with the number of cycles is not affected by the value of the imposed normal load in the case of AP sliding. For the Fe rotation, decreased friction coefficient is obtained when the imposed normal load increases. For both considered AP and Fe kinematics, the roughness of the wear track on the HDPe is not affected by the imposed normal load. It shows a progressive decrease when the number of cycles increases. The wear of HDPe obeys the Archard law and the wear coefficient increases with the normal force. For a given value of normal load, the obtained wear coefficient for the AP sliding is larger than that obtained for Fe rotation. A predominant adhesive wear mechanism was identified for both AP and Fe kinematics. Under the same normal load, damage development in terms of plastic deformation, micro-cracking and debonding is more pronounced for the AP sliding if compared with the Fe rotation. For a given kinematics, the damage severity increases with the normal load. This finding is in good agreement with the predicted values of the wear coefficient according to the Archard law.

关键词： knee prosthesis polyethylene friction wear gait cycle

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Calculation and application of partition coefficients of light hydrocarbons in oil-based mud system

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Petroleum exploration and Development 2022年第4期49卷 906-918页

作者： BeN ABDALLAH Bacem Rabie AHMADI Riadh LYNeN Frederic ReKHISS Farhat laboratoire LR3e.ecole Nationale d’Ingénieurs de Sfax Rte Soukra km 3SfaxTunisia Separation Science Group Department of Organic and Macromolecular ChemistryGhent UniversityKrijgslaan 281-S4B-9000 GhentBelgium

To find out the relationship between the oil-based mud,the formation fluid and the extracted gas,we use a thermodynamic approach based on static headspace gas chromatography technique to calculate the partition coefficients of 47 kinds of light hydrocarbons compounds between nC5 and nC8 in two kinds of oil-based mud-air systems,and reconstruct the original formation fluid composition under thermodynamic *** oil-based drilling mud has little effect on the formation fluid compositions in the range of nC5-nC8(less than 1%for low-toxicity oil-based mud and less than 10%for oil-based mud).For most light hydrocarbon compositions,the partition coefficients obtained by vapor phase calibration and the direct quantitative methods have errors of less than 10%,and the partition coefficients obtained by direct quantitative method are more *** reconstructed compositions of the two kinds of crude oil have match degrees of 91%and 89%with their real compositions,proving the feasibility and accuracy of reconstructing the composition of original formation fluid by using partition coefficients of light hydrocarbon compositions between nC5 and nC8.

关键词： oil-based mud drilling mud gas light hydrocarbon compositions partition coefficients reservoir fluid

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Intracellular behaviour of samarium and europium in lactating mammary gland

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Journal of Rare earths 2012年第3期30卷 274-277页

作者： Ayadi Ahlem Maghraoui Samira el Hili Ali Galle Pierre Tekaya Leila laboratoire de physiologie Faculté de Médecine de Tunis. 15 rue Djebel lakhdhar. 1007 La Rabta. Tunis. Université Tunis El Manar Tunisie laboratoire de microscopie électronique Faculté des Sciences de Tunis Campus universitaire 2092 El Manar II Tunis Université Tunis El Manar Tunisie. Université Tunis El Manar Tunisie Universidade estdual de Santa Cruz CNPq rod. Ilheus-Itabuna Km. 16 Ilheus Ba. Brasil

The subcellular localization of samarium and europium, two rare-earths, increasingly used in both medical and industrial fields, has been studied in several organs such as liver and kidney but never in the mammary gland despite of its importance in the biology of lactation and nutrition domains. The intracellular behaviour of samarium and europium after their intra-peritoneal administration in the lactating mammary gland cells was investigated. The results showed the presence of very electron dense deposits in the glandular epithelial cell lysosomes. These particular lysosomes were never observed in the mammary cell lysosomes of control rats. These intralysosomal deposits were probably composed of insoluble samarium or europium phosphates by analogy with previous studies, the transmission electron microscopy, the ion mass microscopy and the electron probe microanalysis, and other techniques allowing the identification of the chemical structure of the intralysosomal deposits.

关键词： samarium europium transmission electron microscopy (TeM) lysosome mammary gland lactation rare earths

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ecological Study of Two Grasses: <i>Cenchrus ciliaris</i>and <i>Digitaria commutate</i>endangered Autochthonous of the Dry Zone of Tunisia

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Open Journal of Forestry 2014年第4期4卷 349-362页

作者： Imen Dhib Abdessalem Abdessamad Mustapha Ksontini Ali Ferchichi laboratoire d’arido culture et culture oasiènne Institute of the Dry Regions Medenine Route du Djorf Km Medenine Tunisie laboratoire de sylviculture forstière National Institute of Searches in Rural Genius Water and Forest Ariana Tunis

The Saharian ecosystems present an important intensity of rising sensitization to: erosion, and desertification whose impacts are irreversible. On the one hand, the weakness of the yield and the poverty of soil lead to a limited biodiversity. In addition to these difficulties, hydra is the main cause of the rarification of certain pastoral species such as Cenchrus ciliaris and Digitaria commutata. The ecological study underlines a distribution of these species which are very dependent on water resources in the dry regions of Tunisia. The bioclimatic (temperature, pluviometry) variations lead to modifications to these species from one area to another which are translated through several parameters. Concerning the number of bundles, the difference is important. The national park of Bouhedma records the highest number, compared with Bni khdach, Jerba, Khanguit aicha and Matmata respectively. The variation inter-site of study also is considerable by the study of the morphological parameters (height, number and length of leaves by bundle, number of ear) whose bundles of the national park Bouhedma occupy the first class.

关键词： ecological Study Grasses endangered Dry Zone Of Tunisia

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Application of a Geomatics Approach for the Diachronic Study of the Meditterannean Coastline Case of Tangier Bay

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International Journal of Geosciences 2018年第6期9卷 320-336页

作者： Fatima Zahra Salim Mohammed Yassine el Habti Lech-Hab Khadija Ben Hamman Ahmed Raissouni Abdelkrim el Arrim laboratoire "environnement Océanologie et Ressources Naturelles" Dpt. des Sciences dela Terre FST de Tanger Km 9 Route de Ziatine Maroc

The coastline is one of the country’s most important environmental and economic resources. However, it is a delicate and highly coveted environ-ment on which many factors of evolution interact, both anthropogenic and natural. This work is concerned with the diachronic study of the coastline of the Mediterranean coast, particularly the coastal fringe at the level of Tangier Bay. In order to experimentally confirm the numerical models used and to take part in the development of an accurate, reliable and rapid decision support system for the assessment and remediation of the risks of accretion and coastal erosion, the methodology followed consists of the application of automatic analytical techniques, based on a geomatics approach, using a multi-temporal photo-interpretation, a Geographical Information System (GIS) and a computerized data analysis system (DSAS: Digital Shoreline Analysis System). The change rate will be calculated from the multi-date maps (1981-96 and 2017) using the end Point Rate (ePR). To achieve our objective, the study area was divided into three sectors from east to West: el Ghandouri Beach, Malabata Beach and the municipal square adjacent to the port. The GIS analysis of the data obtained shows that the coastline is present by location and for the three periods of comparison of the remarkable zones of erosion and sedimentation.

关键词： Mediterranean Coastline (SIG) Geographic Information System (DSAS) Digital Shoreline Analysis System Accretion erosion

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Impact of train speed on the mechanical behaviours of track-bed materials

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Journal of Rock Mechanics and Geotechnical engineering 2017年第5期9卷 818-829页

作者： Francisco Lamas-Lopez Yu-Jun Cui Nicolas Calon Sofia Costa D’Aguiar Tongwei Zhang laboratoire Navier/CeRMeS Ecole des Ponts ParisTech Marne-la-Vallée 77455 France Département Ligne Voie et Environnement SNCF-Engineering La Plaine St. Denis 93574 France Division Auscultation Modélisation & Mesures SNCF-Research & Development Paris 75012 France

For the 30,000 km long French conventional railway lines(94% of the whole network),the train speed is currently limited to 220 km/h,whilst the speed is 320 km/h for the 1800 km long high-speed ***,there is a growing need to improve the services by increasing the speed limit for the conventional *** paper aims at studying the influence of train speed on the mechanical behaviours of track-bed materials based on field monitoring *** is put on the behaviours of interlayer and subgrade *** selected experimental site is located in Vierzon,*** sensors including accelerometers and soil pressure gauges were installed at different *** vertical strains of different layers can be obtained by integrating the records of accelerometers installed at different trackbed *** experimentation was carried out using an intercity test train running at different speeds from 60 km/h to 200 km/*** test train was composed of a locomotive(22.5 Mg/axle) and 7 'Corail'coaches(10.5 Mg/axle).It was observed that when the train speed was raised,the loadings transmitted to the track-bed ***,the response of the track-bed materials was amplified by the speed rise at different depths:the vertical dynamic stress was increased by about 10% when the train speed was raised from 60 km/h to 200 km/h for the locomotive loading,and the vertical strains doubled their quasistatic values in the shallow ***,the stressestrain paths were estimated using the vertical stress and strain for each train *** loading paths allowed the resilient modulus Mrto be *** was found that the resilient modulus(M_r) was decreased by about 10% when the train speed was increased from 100 km/h to 200 km/***,the damping ratio(D_r) kept stable in the range of speeds explored.

关键词： Field experimentation Conventional track-bed materials Train speed upgrade Mechanical behaviours Reversible modulus Damping ratio

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Tree-ring:a suitable implement for spatial and temporal fire distribution analysis in savanna woodland and dry forest

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Journal of Forestry Research 2015年第2期26卷 435-446页

作者： Franck Sinsin Romain GlèlèKaka? Bettina Orthmann Brice Sinsin laboratoire d’ecologie Appliquée Faculté des Sciences AgronomiquesUniversité d’Abomey-Calavi03 BP 1974 CotonouBénin Laboratory of Biomathematics and Forest estimations Faculté des Sciences AgronomiquesUniversité d’Abomey-Calavi03 BP 1974 CotonouBénin Institute of Biosciences University of Rostock

Based on 120 stem discs collected during3 months of fieldwork along a 12 km route,the history of fires in the Wari Maro Forest（09 1000 N–02 1000e） over the past century in savanna woodland and dry forest was *** major ecological areas are characterized：one highly burnt zone located between two relative less burnt *** analyzing tree rings,246 fire scars were *** scars were caused by 51 fire years,occurring at a mean interval of 2.23 *** 1890 to1965,only 6 years with fires were recorded from sampled *** 1966,no year has passed without *** fire frequency point scale reached 14 *** was the case of Burkea africana,which has been identified as a species tolerant to fire and could be planted to create a natural *** contrast,Anogeissus leiocarpa is highly sensitive to fire,and in a dry forest ecosystem that burns seasonally,it requires a special conservation *** new concepts are described：the rebarking of trees after fire and Mean Kilometer Fire *** first concept was tested with Daniellia oliveri（Rolfe） Hutch ＆ Dalz trees,and the second concept was used to evaluate spatial fire *** demonstrate that savanna woodland and dry forest were subject to a degradation process caused by destructive fires related to vegetation cover clearance and illegal logging.

关键词： Fire ecology Tree-rings Savanna woodland Dry forest Conservation strategies

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A cellular automata traffic flow modeling of desired speed variability

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Chinese Physics B 2013年第1期22卷 574-577页

作者： K. Bentaleb K. Jetto H. ez-Zahraouy A. Benyoussef laboratoire de Magnétisme et de Physique des Hautes energies associéau CNRST (URAC 12) Département de physique B.P. 1014 Facultédes sciences Université Mohammed V Agdal Rabat Morocco ecole Hassania des Travaux Publics km 7 Route d'El Jadida BP8108 Oasis Casablanca Morocco Institute of Nanomaterials and Nanotechnologies INANOTECH MACsIR Rabat Morocco Hassan II Academy of Science and Technology Rabat Morocco

The satisfaction rate of desired velocity in the case of a mixture of fast and slow vehicles is studied by using a cellular automaton method. It is found that at low density the satisfaction rate depends on the maximal velocity. However, the behavior of the satisfaction rate as a function of the coefficient of variance is independent of the maximal velocity. This is in good agreement with empirical results obtained by Lipshtat [Phys. Rev. e 79 066110 （2009）]. Furthermore, our numerical result demonstrates that at low density the satisfaction rate takes higher values, whereas the coefficient of variance is close to zero. The coefficient of variance increases with increasing density, while the satisfaction rate decreases to zero. Moreover, we have also shown that, at low density the coefficient variance depends strongly on the probability of overtaking.

关键词： traffic celluar automata satisfaction coefficient desired speed

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