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Journal of Renewable Materials 2018年第3期6卷 288-298页

作者： Kahina Iggui mustapha Kaci Nicolas Le Moigne Anne Bergeret Centre des Matériaux des Mines d’Alès(C2MA) IMT Mines AlesUniversitéde Montpellier30100 AlèsFrance Laboratory of Advanced Polymer Materials University of BéjaïaBéjaïa Province06000Algeria Institut de Technologie UniversitéAkli Mohand OulhadjBouira 10000Algeria

The effects of accelerated photooxidation on the molecular weight and thermal and mechanical properties of Cast PHBV and PHBV/Cloisite 30B(3 wt%)bionanocomposites are investigated *** size exclusion chromatography(SEC)analysis,a significant decrease in both weight and number average molecular weights was observed for all irradiated samples over time,resulting from the chain scission *** scanning calorimetry(DSC)data indicated a decrease in degree of crystallinity and melting temperature after UV exposure,with the appearance of double melting peaks related to the changes in the crystal structure of *** stability,tensile and thermo-mechanical properties were also reduced consecutively in photooxidation,being more pronounced for Cast *** study shows that the incorporation of Cloisite 30B in PHBV provides a better resistance to photooxidation in comparison with the neat polymer.

关键词： Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) organo-modified montmorillonite bionanocomposites accelerated photooxidation and degradation

Blockchain Merkle-Tree Ethereum Approach in Enterprise Multitenant Cloud Environment

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Computers, Materials & Continua 2023年第2期74卷 3297-3313页

作者： Pooja Dhiman Santosh Kumar Henge Sartaj Singh Avinash Kaur Parminder Singh mustapha Hadabou School of Computer Applications Lovely Professional UniversityPhagwara144001India School of Computer Science and Engineering Lovely Professional UniversityPhagwara144001India School of Computer Science Mohammed VI Polytechnic UniversityBen Guerir43150Morocco

This research paper puts emphasis on using cloud computing with Blockchain(BC)to improve the security and privacy in a *** security of data is not guaranteed as there is always a risk of leakage of users’*** can be used in a multi-tenant cloud environment(MTCE)to improve the security of data,as it is a decentralized *** is saved in unaltered ***,Blockchain is not owned by a single *** encryption process can be done using a Homomorphic encryption(HE)algorithm along with hashing technique,hereby allowing computations on encrypted data without the need for *** research paper is composed of four objectives:Analysis of cloud security using Blockchain technology;Exceptional scenario of Blockchain architecture in an enterprise-level MTCE;Implementation of cipher-text policy attribute-based encryption(CPABE)algorithm;Implementation of Merkle tree using Ethereum(MTuE)in a Multi-tenant *** of these four objectives,the main focus is on the implementation of CP-ABE ***-ABE parameters are proposed for different levels of *** levels include inner tenant,outer tenant,Inner-Outer-Tenant,Inner-Outer-External-Tenant,Outer-Inner-Tenant,External-Outer-Inner-Tenant and the parameters such as token,private key,public key,access tree,message,attribute set,node-level,cipher-text,salting which will help in providing better security using CP-ABE algorithm in a multitenant environment(MTE)where tenants can be provided with different levels of security and achieved 92 percentage of authenticity and access-control of the data.

关键词： Blockchain(BC) merkle tree using ethereum(MTuE) multi-tenant environment(MTE) homomorphic encryption(HE) ciphertext policy attribute-based encryption(CP-ABE)

Scalability of biomass-derived graphene derivative materials as viable anode electrode for a commercialized microbial fuel cell: A systematic review

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Chinese Journal of Chemical Engineering 2023年第3期55卷 277-292页

作者： mustapha Omenesa Idris Claudia Guerrero-Barajas Hyun-Chul Kim Asim Ali Yaqoob Mohamad Nasir Mohamad Ibrahim School of Chemical Sciences Universiti Sains Malaysia11800 PenangMalaysia Department of Pure and Industrial Chemistry Kogi State UniversityP.M.B 1008 AnyigbaKogi StateNigeria Laboratorio de Biotecnologia Ambiental Departamento de BioprocesosUnidad Profesional Interdisciplinaria de BiotecnologiaInstituto Politecnico NacionalAv.Acueducto s/nCol.Barrio La Laguna Ticoman07340 Mexico CityMexico Research Institute for Advanced Industrial Technology College of Science and TechnologyKorea UniversitySejong 30019Republic of Korea

Microbial fuel cell(MFC) is an advanced bioelectrochemical technique that can utilize biomass materials in the process of simultaneously generating electricity and biodegrading or bio transforming toxic pollutants from wastewater. The overall performance of the system is largely dependent on the efficiency of the anode electrode to enhance electron transportation. Furthermore, the anode electrode has a significant impact on the overall cost of MFC setup. Hence, the need to explore research focused towards developing cost-effective material as anode in MFC. This material must also have favourable properties for electron transportation. Graphene oxide(GO) derivatives and its modification with nanomaterials have been identified as a viable anode material. Herein, we discussed an economically effective strategy for the synthesis of graphene derivatives from waste biomass materials and its subsequent fabrication into anode electrode for MFC applications. This review article offers a promising approach towards replacing commercial graphene materials with biomass-derived graphene derivatives in a view to achieve a sustainable and commercialized MFC.

关键词： Microbial fuel cell Biomass Anode fabrication Catalyst Design Cost-effective performance

Formulating layered adjustable autonomy for unmanned aerial vehicles

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International Journal of Intelligent Computing and Cybernetics 2017年第4期10卷 430-450页

作者： Salama A.Mostafa Mohd Sharifuddin Ahmad Aida mustapha Mazin Abed Mohammed Faculty of Computer Science and Information Technology Universiti Tun Hussein Onn MalaysiaBatu PahatMalaysia College of Information Technology Universiti Tenaga NasionalKajangMalaysia Planning and Follow Up Department University of AnbarAnbarIraq

Purpose–The purpose of this paper is to propose a layered adjustable autonomy(LAA)as a dynamically adjustable autonomy model for a multi-agent *** is mainly used to efficiently manage humans’and agents’shared control of autonomous systems and maintain humans’global control over the ***/methodology/approach–The authors apply the LAA model in an agent-based autonomous unmanned aerial vehicle(UAV)*** UAV system implementation consists of two parts:software and *** software part represents the controller and the cognitive,and the hardware represents the computing machinery and the actuator of the UAV *** UAV system performs three experimental scenarios of dance,surveillance and search *** selected scenarios demonstrate different behaviors in order to create a suitable test plan and ensure significant ***–The results of the UAV system tests prove that segregating the autonomy of a system as multidimensional and adjustable layers enables humans and/or agents to perform actions at convenient autonomy ***,reducing the adjustable autonomy drawbacks of constraining the autonomy of the agents,increasing humans’workload and exposing the system to ***/value–The application of the LAA model in a UAV manifests the significance of implementing dynamic adjustable *** the autonomy within three phases of agents run cycle(taskselection,actions-selection and actions-execution)is an original idea that aims to direct agents’autonomy toward performance *** agents’abilities are well exploited when an incompetent agent switches with a more competent one.

关键词： Unmanned aerial vehicle Multi-agent system Adjustable autonomy Autonomous agent

Effect of Recycling Cycles on the Mechanical and Damping Properties of Short Alfa Fibre Reinforced Polypropylene Composite

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Journal of Renewable Materials 2019年第3期7卷 253-267页

作者： Fatima Ezzahra El Abbassi mustapha Assarar Rezak Ayad Hamid Sabhi Stephane Buet nouzha Lamdouar Department of Civil Engineering University of Cadi AyyadMorocco Laboratory of Engineering and Material Sciences University of Reims Champagne-ArdenneFrance Laboratory of Simulation Instrumentation and MeasurementUniversity of Mohammed VMorocco

This paper aims at studying the effect of recycling on the static and dynamic properties of short alfa fibre reinforced *** this purpose,alfa fibres reinforced composites were elaborated by an injection moulding process and were subjected to different mechanical recycling ***,non-recycled and recycled materials were subjected to static tests and Dynamic Mechanical Analysis(DMA)to evaluate the effect of recycling on their ***,the effects of alkali and salt water treatments on the static and dynamic properties of the alfa composite were also *** obtained results show that tensile and flexural properties of alfa fibres reinforced composites decrease during recycling ***,the recycling induces a drop in the storage modulus and enhances the loss factor of these *** composites with alfa fibre especially the alkali treated composite show the same resistance to recycling as composites with hemp ***,SEM observations indicate a decrease in the fibres dimension with the recycling cycles,especially for alfa fibres,which can explain the decrease in the properties of the alfa composite during recycling operations.

关键词： Alfa fibre hemp fibre eco-composites recycling mechanical properties dynamic properties

Effect of the synthesis route on the structural and dielectric properties of SrBi1.8Y0.2Nb2O9 ceramics

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1304-1312页

作者： Mohamed Afqir Amina Tachafine Didier Fasquelle Mohamed Elaatmani Jean-Claude Carru Abdelouahad Zegzouti mustapha El Hammioui Laboratoire des Sciences des Matériaux Inorganiques et leurs Applications Facultédes Sciences SemlaliaUniversitéCadi AyyadMarrakech 40000Maroc Unite de Dynamique et Structure des Materiaux Moleculaires Universite du Littoral-Cote d’OpaleCalais 62100France Laboratoire de recherche sur la réactivitédes matériaux et l’optimisation des procédés Facultédes Sciences SemlaliaUniversitéCadi Ayyad 40000MarrakechMaroc

This work is devoted to the synthesis and characterization of yttrium-doped SrBi_2Nb_2O_9 ceramics prepared by three methods: solid state reaction, co-precipitation, and hydrothermal. Multiple characterizations, specifically scanning electron microscopy(SEM), X-ray powder diffraction(XRD), and Fourier transform infrared spectroscopy(FTIR), were used to validate the structural feature. The crystallite size was estimated by Scherrer's formula and the Williamson–Hall plot. The effect of the process on the band intensities of the FTIR spectra was investigated. The crystallite size and microstructure of ceramics prepared from different synthesis processes were strongly influenced by the sinterability. SEM images revealed nanograin ceramics for materials prepared by co-precipitation and hydrothermal methods and micrograin ceramics prepared by the solid state method. The synthesized compounds underwent phase transitions at 480–465°C. The dielectric and electrical properties of these Y-doped SrBi_2Nb_2O_9 ceramics appear to be dependent on the grain size.

关键词： Aurivillius,synthesis routes crystallite size microstructure dielectric

Meso-Archean to Mid-Paleozoic Granitoids in Oulad Dlim Massif(the Pericratonic Terrane of the Reguibat Shield,West African Craton,Morocco):Petrology,Geochemistry,Geochronology and Geological Implications

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Journal of Earth Science 2022年第5期33卷 1152-1165页

作者： Haissen Faouziya Montero Pilar Molina Jose Francisco Lodeiro Francisco Mouttaqi Abdellah Chaib mustapha Bea Fernando LGAGE Département de GéologieFacultédes Sciences Ben M’sikHassan II University of CasablancaB.P.5366MaarifCasablancaMaroc Department of Mineralogy and Petrology University of GranadaCampus FuentenuevaGranada18002Spain Office National des Hydrocarbures et des Mines 5 Avenue Moulay HassanRabatMaroc

The Oulad Dlim Massif,adjacent to the Reguibat Shield in South Morocco was considered up to now as part of the Variscan belt(Mauritanides)with a polyphase geologic history and a complex geodynamic evolution implicating oceans closures and accretion of exotic terranes(Avalonian and Meguman)during the Variscan-Alleghanian *** use of modern technology to characterize the petrology,the geochemistry and the geochronology of the lithological units forming this region,combined to field surveys has led to an updated geological architecture and different geological *** Oulad Dlim Massif is mainly a deformed Archean terrane,as recorded by its eastern and western sectors,dominated in its central part by a bimodal felsic-mafic magmatism forming the Ediacaran *** study of these magmatic complexes supports strongly the intracontinental origin of this bimodal magmatism *** oceanic origin published before in *** exploration of this massif conducted also to the identification of a Silurian-Devonian sector in the western ***,up to date,different magmatic events lasting from the Meso-Archean to the Cretaceous are recorded in the Oulad Dlim Massif rocks,among them different generations of granitoids are *** data on granitoids from the Ediacaran sector are presented in this *** recent data demonstrates that Oulad Dlim Massif has been affected by the main Ediacaran–Cambrian extensional event widely documented in other structural domains of Morocco and other parts of North ***,the study of the Silurian-Devonian sector rocks highlighted the presence of a Caledonian tectonic event challenging the ideas about the paleogeography of this part of northwestern Africa and its geological evolution during the ***,despite the significant contribution of this extensive survey and the abundance of data on the Oulad Dlim Massif,more studies are required to reconstruct the puzzle at plate tectonic scale.

关键词： Archean Ediacaran bimodal magmatism extension intracontinental rifting Caledonian tectonic event petrology geochemistry

Antibacterial, cytotoxicity and wound healing assessments of amine-functionalised zeolite Y

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Particuology 2019年第4期17卷 116-123页

作者： Muhammad Hariz Asraf Nik Ahmad Nizam Nik Malek Khairunadwa Jemon Nor Suriani Sani mustapha Salisu Muhammad Department of Biosciences Faculty of Science Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia Centre for Sustainable Nanomaterials (CSNano) Ibnu Sina Institute for Scientific and Industrial Research (IS1-ISIR) Universiti Teknologi Malaysia 81310 UTMJohor Malaysia Office of Deputy Vice Chancellor (Research and Innovation) Universiti Teknologi Malaysia 81310 UTM Skudai Johor Malaysia

The antibacterial activities,cytotoxicity,and wound healing of amine(3-aminopropyltriethoxysilane (APTES))-functionalised zeolite Y against normal human fibroblast cells were *** characterisation of unmodified and amine-functionalised zeolites Y (Z,ZA 0.04,ZA 0.4,and ZA 0.6) by Fourier transform infrared spectroscopy,X-ray powder diffraction,and energy dispersive X-ray analysis proved that the APTES molecules were grafted onto the zeolite Y surface without distorting its framework *** amine-functionalised zeolite Y samples possessed antibacterial activities against several ATCC bacteria that were correlated with the increased amount of APTES on the zeolite Y ***,when a higher concentration of APTES was grafted on the zeolite Y,higher cytotoxicity was observed against the fibroblast *** the ZA 0.6 sample (zeolite Y functionalised with 0.6 M of APTES) had higher antibacterial activity,it was cytotoxic to the ***,the selection of an antibacterial agent for human treatment purposes must also consider its cytotoxicity effect against human cells to ensure it is biocompatible.

关键词： Zeolite Y Amine functionalised zeolite Functionalisation Antibacterial agent Cytotoxicity

Factors influencing IOP changes in postmenopausal women

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Family Medicine and Community Health 2018年第3期6卷 97-103页

作者： Chin P.Siuw Suresh Vasudevan Mushawiathi mustapha Ophthalmology Department Sultanah Aminah HospitalJohor BahruJohorMalaysia Ophthalmology Department Pusat Perubatan UniversityKebangsaanJalan Yaacob LatifBandar Tun RazakWilayah Persekutuan Kuala LumpurMalaysia

Objective:Intraocular pressure(IOP)is essential in maintaining normal function of the *** IOP is associated with *** physiological factors,including age and hormones,can cause variation in *** study was designed to investigate IOP changes in postmenopausal women and the associated factors,which included sex hormones and body mass index(BMI).Methods:This was a cross-sectional ***-eight women were recruited:49 premenopausal women and 49 postmenopausal *** between the two groups were *** influence of estradiol,progesterone,testosterone,and BMI on IOP was analyzed by a multivariate method.P<0.05 was considered ***:The age of the premenopausal group was 47.14±3.93 years and that of the postmenopausal group was 52.10±3.04 *** other factors in both groups,which included BMI,blood pressure,and central cornea thickness,were not significantly *** mean IOP in the postmenopausal group was significantly higher than the mean IOP in the premenopausal group(15.26±2.96 mm Hg vs.14.07±2.65 mm Hg,P=0.04).BMI had a weak positive correlation with IOP in premenopausal women(r=0.31,P=0.03).Estradiol was less likely to influence IOP changes in the postmenopausal group as compared with the premenopausal group(B=−0.021,P=0.002).IOP was not significantly related to progesterone and testosterone ***:Menopausal status has a significant effect on IOP,with a significant increase in IOP seen in postmenopausal women as shown by our *** was shown to be a protective factor in reducing IOP among postmenopausal *** understanding of the influence of postmenopausal status and sex hormones on IOP,glaucoma management may be improved and the target group for disease screening may be more specific.

关键词： Intraocular pressure postmenopausal hormones body mass index

Versatile synthesis of cadalene and iso-cadalene from himachalene mixtures:Evidence and application of unprecedented rearrangements

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Chinese Chemical Letters 2020年第7期31卷 1851-1854页

作者： mustapha Ait El Had Abdelouahd Oukhrib Mohamed Zaki Martine Urrutigoity Ahmed Benharref Remi Chauvin Laboratoire de Chimie Biomoleculaire Substances Naturelies et Reactivite(URAC 16)Faculte des Sciences SemlaliaUniversite Cadi AyyadB.P.2390MarrakechMorocco CNRS LCC(Laboratoire de Chimie de Coordination)BP 4409931077Toulouse Cedex 4France INP-ENSIACET 4 allee Emile Monso31030Toulouse CedexFrance Universite de Toulouse UPSICT-FR 259931062Toulouse Cedex 9France

From a mixture of α-,β-and y-himachalenes extracted from waste wood of Atlas cedar(Cedrus atlantica),cadalene(1,6-dimethyl-4-isopropylnaphthalene)and iso-cadalene(1,6-dimethyl-3-isopropylnaphthalene)were produced in two steps with up to 71%±5%yield through the ar-himachalene intermediate using I2 and/or AlCl3 as *** selectivity is shown to sharply depend on the operating conditions:while I2/AlCl3 in dichloromethane promotes the formation of cadalene,the formation of iso-cadalene is favored in the presence of AlCl3 in *** bicyclic aromatic compounds were thus obtained through unique rearrangements involving sequential C—C bond cleavage/fo rmation and hydride transfer *** the absence of AlCl3 or I2,dihydrocurcumene was also found to be formed with up to 70%selectivity.A tentative mechanism is proposed and discussed.

关键词： Aromatic reactivity Cadalenes Dihydrocurcumene Himachalenes Rearrangements