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Journal of Renewable Materials 2018年第5期6卷 464-476页

作者： Marwa Abida jamel Mars Florian Gehring Alexandre Vivet Fakhreddine Dammak Normandie Univ ENSICAENUNICAENCEACNRSCIMAP14000 CaenFrance Mechanical Modeling and Manufacturing Laboratory(LA2MP) National School of Engineers of SfaxUniversity of SfaxB.P 1173-3038SfaxTunisia Laboratory of Electromechanical Systems(LASEM) National Engineering School of SfaxUniversity of SfaxB.P.1173-3038SfaxTunisia

Based on experimental test results,flax fiber reinforced polymer composites are characterized by nonlinear visco-elastoplastic *** aim of this work is to model the quasi-unidirectional flax fiber reinforced composite behavior through a three dimensional formulation with orthotropic elasticity and orthotropic plasticity using Hill *** isotropic hardening and Johnson Cook parameters are identified from unidirectional tensile tests at different strain *** adjustment of Hill’s yield criterion is developed based on yield stresses obtained in tensile tests at different *** numerical integration of the constitutive equations is implemented in a user-defined material,UMAT subroutines for the commercial finite element code *** model parameters are identified using tensile tests,the model needs to be validated by confronting it with other experimental *** is why experimental and numerical three-point bending tests are carried out in order to validate the proposed model with tests that have not served for the ***,a numerical parametric study on low velocity impact of a flax/epoxy composite circular plate is investigated.

关键词： Visco-elastoplasticity anisotropic behavior impact simulation flax fiber composites

Crystallization Behavior of Fe_(50−x)Cr_(15)Mo_(14)C_(15)B_(6)M_(x)(x=0,2 and M=Y,Gd)Bulk Metallic Glasses and Ribbons by in situ High Temperature X-Ray Diffraction

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Chinese Physics Letters 2012年第10期29卷 235-238页

作者： Badis Bendjemil Abderrezak Bouchareb Ahmed Belbah jamel Bougdira Rafael Piccin Marcello Baricco LEREC Department of PhysicsUniversity of Badji-mokhtar-AnnabaAlgeria 2Department of Mechanical EngineeringFaculty of Science and TechnologyUniversity of 8 Mai 1945 GuelmaAlgeria 3Institut Jean LAMOURUniversity Henri poincarréNancyFrance 4IFM/NISUniversitàdi TorinoVia P.Giuria 910125 TorinoItaly

The effect of rare earth addition on thermal stability of Fe_(50−x)Cr_(15)Mo_(14)C_(15)B_(6)M_(x)(x=0,2 and M=Y,Gd)is *** and structural properties are measured using differential scanning calorimetry and x-ray diffraction,*** microstructure is observed by using a scanning electron microscope,and chemical composition is checked by energy dispersive spectroscopy *** effect of high temperature on the isothermal crystallization of Fe_(50−x)Cr_(15)Mo_(14)C_(15)B_(6)M_(x)(x=0,2 and M=Y,Gd)bulk metallic glass and ribbons is investigated by high-temperature x-ray *** is found that the crystallization behavior of Fe_(50−x)Cr_(15)Mo_(14)C_(15)B_(6)M_(x)(x=0,2 and M=Y,Gd)bulk metallic glass strongly depends on the annealing *** different crystallization behavior is believed to be due to the different structures that the metallic glass possesses at different temperatures.

关键词： microstructure crystallization metallic

Acute effects of chlorpyryphos-ethyl and secondary treated effluents on acetylcholinesterase and butyrylcholinesterase activities in Carcinus maenas

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Journal of Environmental Sciences 2009年第10期21卷 1467-1472页

作者： Jihene Ghedira jamel Jebali Zied Bouraoui Mohamed Banni Lassaad Chouba Hamadi Boussetta Laboratory of Biochemical and Environmental Toxicology Higher Institute of Agriculture Chott-Mariem 4042 Sousse Tunisia Chemical Laboratory Higher Institute of Marine Sciences and Technology La Goulette Center 2060 Tunisia

The acute effects of commercial formulation of chlorpyrifos-ethyl （Dursban ） and the secondary treated industrial/urban effluent （STIUE） exposure on acetylcholinesterase （ACHE） and butyrylcholinesterase （BuChE） activities in hepatopancreas and gills of Mediterranean crab Carcinus maenas were investigated. After 2 d of exposure to chlorpyriphos-ethyl, the AChE activity was inhibited in both organs at concentrations of 3.12 and 7.82 μg/L, whereas the BuCHE was inhibited only at higher concentration 7.82 μg/L of commercial preparation Dursban~. The exposure of crabs to Dursban （3.12 μg/L） showed a significant decrement of ACHE activity at 24 and 48 h, whereas the BuChE was inhibited only after 24 h and no inhibition for both enzymes was observed after 72 h. Moreover, a significant repression of AChE activity was observed in both organs of C. maenas exposed to 5% of STIUE. Our experiments indicated that the measurement of AChE activity in gills and hepatopancreas of C. maenas would be useful biomarker of organophosphorous （OP） and of neurotoxic effects of STIUE in Tunisia.

关键词： acetylcholinesterase butyrylcholinesterase organophosphorous Dursban secondary treated industrial/urban effluent Carcinus maenas

Characterization and physicochemical aspects of novel cellulose-based layered double hydroxide nanocomposite for removal of antimony and fluoride from aqueous solution

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Journal of Environmental Sciences 2021年第4期33卷 301-315页

作者： Hanen Bessaies Sidra Iftekhar Muhammad Bilal Asif jamel Kheriji Chaker Necibi Mika Sillanpää Bechir Hamrouni Laboratory of Desalination and Water Treatment LR19ES01 Faculty of Sciences of TunisTunis El Manar UniversityEl Manar I 2092Tunisia Department of Environmental Engineering University of Engineering and Technology TaxilaTaxila 47050Pakistan Department of Applied Physics University of Eastern FinlandKuopio 70210Finland A lnstitute of Environmental Engineering and Nano-Technology Tsinghua Shezhen International Graduate SchoolTsinghua UniversityShenzhen 518055China International Water Research Institute Mohammed VI Polythechnic UniversityGreen City Ben Guerir 43150Morocco Institute of Research and Development Duy Tan UniversityDa Nang 550000Vietnam Faculty of Environment and Chemical Engineering Duy Tan UniversityDa Nang 550000Vietnam School of Civil Engineering and Surveying Faculty of HealthEngineering and SciencesUniversity of Southern QueenslandWest StreetToowoombaQLD 4350Australia Department of Chemical Engineering School of MiningMetallurgy and Chemical EngineeringUniversity of JohannesburgDoornfontein 2028South Africa

A series of novel adsorbents composed of cellulose(CL)with Ca/Al layered double hydroxide(CC_(x)A;where x represent the Ca/Al molar ratio)were prepared for the adsorption of antimony(Sb(V))and fluoride(F^(-))ions from aqueous *** CC_(x)A was characterized by Fourier-transform infrared spectroscopy(FTIR),Brunauer–Emmett–Teller(BET),elemental analysis(CHNS/O),thermogravimetric analysis(TGA-DTA),zeta potential,X-ray photoelectron spectroscopy(XPS)and scanning electron microscopy with energy dispersive Xray spectroscopy(SEM-EDX)*** effects of varying parameters such as dose,pH,contact time,temperature and initial concentration on the adsorption process were *** to the obtained results,the adsorption processes were described by a pseudo-second-order kinetic *** adsorption isotherm model provided the best fit for the experimental data and was used to describe isotherm *** maximum adsorption capacity was found to be 77.2 and 63.1 mg/g for Sb(V)and F^(-),respectively by CC_(3)A(experimental conditions:pH 5.5,time 60 min,dose 15 mg/10 mL,temperature 298 K).The CC_(3)A nanocomposite was able to reduce the Sb(V)and F^(-)ions concentration in synthetic solution to lower than 6μg/L and 1.5 mg/L,respectively,which are maximum contaminant levels of these elements in drinking water according to WHO guidelines.

关键词： Layered double hydroxide Adsorption Antimony removal Fluoride removal Kinetics

Micro Manipulation Using Magnetic Microrobots

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Journal of Bionic Engineering 2016年第4期13卷 515-524页

作者： Hoyeon Kim jamel Ali U Kei Cheang Jinwoo Jeong din Seok Kim Min dun Kim Department of Mechanical Engineering Southern Methodist University Dallas TX75272 USA Department of MechanicaI Engineering and Mechanics Drexel University Philadelphia PA 19104 USA Center for Bionics Korea Institute of Science and Technology 5 Hwarang-ro 14-gil Seongbuk-gu Seou102792 Republic of Korea

When developing microscale robotic systems it is desired that they are capable of performing microscale tasks such as small scale manipulation and transport. In this paper, we demonstrate the transport of microscale objects using single or multiple microrobots in low Reynolds number fluidic environment. The microrobot is composed of a ‘U＇ shaped SU-8 body, coated on one side with nickel. Once the nickel coating is magnetized, the motion of the microrobots can be driven by external magnetic fields. To invoke different responses from two microrobots under a global magnetic field, two batches of microrobots were fabricated with different thicknesses of nickel coating as a way to promote heterogeneity within the microrobot population. The heterogeneity in magnetic content induces different spatial and temporal responses under the same control input, resulting in differences in movement speed. The nickel coated microstructure is manually controlled through a user interface developed using C＋＋. This paper presents a control strategy to navigate the microrobots by controlling the direction and strength of ex- ternally applied magnetic field, as well as orientation of the microrobots based on their polarity. In addition, multiple micro- robots are used to perform transport tasks.

关键词： microrobot magnetic control microtransport magnetic polarity micromanipulation

Design of a Five-Band Dual-Port Rectenna for RF Energy Harvesting

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Computers, Materials & Continua 2021年第10期69卷 487-501页

作者： Surajo Muhammad Jun Jiat Tiang Sew Kin Wong jamel Nebhen Amjad Iqbal Centre for Wireless Technology Faculty of EngineeringMultimedia UniversityCyberjaya63100Malaysia College of Computer Science and Engineering Prince Sattam Bin Abdulaziz UniversityAlkharj11942Saudi Arabia

This paper proposed the design of a dual-port rectifier with multifrequency *** RF rectifier is achieved using a combination of L-section inductive impedance matching network(IMN)at Port-1 with a multiple stubs impedance transformer at *** fabricated prototype can harvest RF signal from GSM/900,GSM/1800,UMTS/2100,Wi-Fi/2.45 and LTE/2600 frequency bands at(0.94,1.80,2.10,2.46,and 2.63 GHz),*** rectifier occupies a small portion of a PCB board at 0.20λg×0.15λ*** proposed circuit realized a measured peak RF-to-dc(radio frequency direct current)power conversion efficiency(PCE)of(21%,22.76%,25.33%,21.57%,and 22.14%)for an input power of−20 *** RF harvester attains a measured peak RF-to-dc PCE of 72.70%and an output dc voltage of 154 mV for an input power of 3 dBm at 2.46 *** of the proposed rectifier in the ambiance gives a peak dc output voltage of 376.1 mV from the five signal ***,a low-powered bq25504-674 evaluation module(EVM)is integrated with the *** module boost and drive the rectifier output dc voltage to 945 *** performance of the proposed rectifier in the ambiance environment makes it a suitable module for low-powered RF applications.

关键词： RF energy harvesting impedance matching network power conversion efficiency multi-band rectifier

Field testing innovative differential geospatial and photogrammetric monitoring technologiesin mountainous terrain near Ashcroft,British Columbia,Canada

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Journal of Mountain Science 2021年第1期18卷 1-20页

作者： David HUNTLEY Peter BOBROWSKY Roger MACLEOD Robert COCKING jamel JOSEPH Drew ROTHERAM-CLARKE Geological Survey of Canada 1500-605 Robson StreetVancouverBritish ColumbiaV6B 5J3Canada Geological Survey of Canada 9860 West Saanich RoadSidneyBritish ColumbiaV8L 4B2Canada

This paper presents a novel approach to continuously monitor very slow-moving translational landslides in mountainous terrain using conventional and experimental differential global navigation satellite system(d-GNSS)technologies.A key research question addressed is whether displacement trends captured by a radio-frequency“mobile”d-GNSS network compare with the spatial and temporal patterns in activity indicated by satellite interferometric synthetic aperture radar(InSAR)and unmanned aerial vehicle(UAV)*** testing undertaken at Ripley Landslide,near Ashcroft in south-central British Columbia,Canada,demonstrates the applicability of new geospatial technologies to monitoring ground control points(GCPs)and railway infrastructure on a landslide with small and slow annual displacements(<10 cm/yr).Each technique records increased landslide activity and ground displacement in late winter and early *** this interval,river and groundwater levels are at their lowest levels,while ground saturation rapidly increases in response to the thawing of surficial earth materials,and the infiltration of snowmelt and runoff occurs by way of deep-penetrating tension cracks at the head scarp and across the main slide *** over the last decade provides vital information for government agencies,national railway companies,and other stakeholders to understand geohazard risk,predict landslide movement,improve the safety,security,and resilience of Canada’s transportation infrastructure;and reduce risks to the economy,environment,natural resources,and public safety.

关键词： Landslide Change detection monitoring Global Navigation Satellite System Real-Time Kinematic System GeocubeTM Bathymetric Survey Unmanned Aerial Vehicle Interferometric Synthetic Aperture Radar

Synthesis of novel adsorbent by intercalation of biopolymer in LDH for the removal of arsenic from synthetic and natural water

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Journal of Environmental Sciences 2020年第5期32卷 246-261页

作者： Hanen Bessaies Sidra Iftekhar Bhairavi Doshi jamel Kheriji Mohamed Chaker Ncibi Varsha Srivastava Mika Sillanpaa Bechir Hamrouni Laboratory of Desalination and Water Treatement LR19ES01 Faculty of Sciences of TunisTunis El Manar University2092El Manar ITunisia Department of Separation Science Lappeenranta-Lahti University of Technology(LUT)Sammonfeatu 12FI-50130MikkeliFinland International Water Research Institute MohammedⅥPolytechnic UniversityCity Ben Guerir 43150Morocco Department of Civil and Environmental Engineering Florida International UniversityMiamiFL 33174USA Department of Environmental Engineering University of Engineering and TechnologyTaxilaPakistan

This study focuses on the synthesis of nanocomposites named CCA and CZA that were prepared by the incorporation of cellulose(CL)in the Ca/Al and Zn/Al layered double hydroxide(LDH),*** materials were then used for the uptake of As(Ⅲ)and As(V)from aqueous *** of both nanocomposites(CCA and CZA)was done using FTIR and Raman analysis to identify the functional groups,N2 adsorption-desorption isotherms to determine the specific surface area and pore geometry and XPS analysis to obtain the surface atomic *** other characters were investigated using simultaneous TGA and DTA and elemental chemical analysis(CHNS/O).The crystallinity of the prepared nanocomposites was displayed by XRD ***,the sheet-like structure of the LDHs and the irregularity of surface morphology with porous structure were observed by TEM and SEM *** of maximum adsorption capacity was adjusted using different parameters including pH,contact time and adsorbent *** pseudo-second-order model was in good fitting with kinetics *** adsorption isotherm results showed that CZA exhibits better adsorption capacity for As(Ⅲ)than CCA and the Langmuir isotherm model described the data well for both *** studies illustrated the endothermic nature of CCA and exothermic nature on CZA,as well as the fact that the adsorption process is spontaneous.A real water sample collected from well located in Gabes(Tunisia),has also been *** obtained experimental results were confirmed that these sorbents are efficient for the treatment of hazardous toxic species such as.

关键词： Layered double hydroxide Adsorption Arsenic removal Kinetics Natural water treatment

Toward Optimal Cost-Energy Management Green Framework for Sustainable Future Wireless Networks

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Computers, Materials & Continua 2021年第7期68卷 1321-1339页

作者： Mohammed H.Alsharif Abu Jahid Mahmoud A.Albreem Peerapong Uthansakul jamel Nebhen Khalid Yahya Department of Electrical Engineering College of Electronics and Information EngineeringSejong UniversitySeoul05006Korea Department of Electrical and Computer Engineering University of OttawaOttawaK1N 6N5ONCanada Department of Electronics and Communications Engineering A’Sharqiyah UniversityIbra400Oman School of Telecommunication Engineering Suranaree University of TechnologyNakhon RatchasimaThailand College of Computer Engineering and Sciences Prince Sattam bin Abdulaziz UniversityAlkharj11942Saudi Arabia Department of Mechatronics Faculty of Engineering and ArchitectureIstanbul Gelisim UniversityIstanbul34310Turkey

The design of green cellular networking according to the trafc arrivals has the capability to reduce the overall energy consumption to a cluster in a cost-effective *** cell zooming approach has appealed much attention that adaptively ofoads the BS load demands adjusting the transmit power based on the trafc intensity and green energy ***,the researchers are focused on implementing renewable energy resources,which are considered the most attractive practices in designing energy-efcient wireless networks over the long term in a cost-efcient way in the existing *** utilization of available solar can be adapted to acquire cost-effective and reliable power supply to the BSs,especially that sunlight is free,available everywhere,and a good alternative energy option for the remote ***,planning a photovoltaic scheme necessitates viability assessment to avoid poor power supply,particularly for ***,cellular operators need to consider both technical and economic factors before the implementation of solar-powered *** paper proposed the usercentric cell zooming policy of solar-powered cellular base stations taking into account the optimal technical criteria obtained by the HOMER software *** results have shown that the proposed system can provide operational expenditure(OPEX)savings of up to 47%.In addition,the efcient allocation of resource blocks(RBs)under the cell zooming technique attain remarkable energy-saving performance yielding up to 27%.

关键词： Wireless networks beyond 5G green communications sustainability OPEX communication systems

A simplified two-dimensional boundary element method with arbitrary uniform mean flow

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Theoretical & Applied Mechanics Letters 2017年第4期7卷 207-221页

作者： Bassem Barhoumi Safa Ben Hamouda jamel Bessrour University of Tunis El Manar National Engineering School of Tunis MAI Laboratory BP 37 El Belvedere 1002 Tunis Tunisia

To reduce computational costs, an improved form of the frequency domain boundary element method（BEM） is proposed for two-dimensional radiation and propagation acoustic problems in a subsonic uniform flow with arbitrary orientation. The boundary integral equation（BIE） representation solves the two-dimensional convected Helmholtz equation（CHE） and its fundamental solution, which must satisfy a new Sommerfeld radiation condition（SRC） in the physical space. In order to facilitate conventional formulations, the variables of the advanced form are expressed only in terms of the acoustic pressure as well as its normal and tangential derivatives, and their multiplication operators are based on the convected Green＇s kernel and its modified derivative. The proposed approach significantly reduces the CPU times of classical computational codes for modeling acoustic domains with arbitrary mean flow. It is validated by a comparison with the analytical solutions for the sound radiation problems of monopole,dipole and quadrupole sources in the presence of a subsonic uniform flow with arbitrary orientation.

关键词： Two-dimensional convected Helmholtz equation Two-dimensional convected Green’s function Two-dimensional convected boundary element method Arbitrary uniform mean flow Two-dimensional acoustic sources