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Influence and Dispersion of Nanofiber of Wood Modified on Properties of Cement Based Mortars

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Journal of Renewable Materials 2019年第7期7卷 631-641页

作者： Fadhel Aloulou Alila Sabrine habib sammouda LabEM-LR11ES34:Laboratory of Energy and Materials University of SousseTunisia LMSE:Laboratoire Sciences des Matériaux et Environnement University of SfaxTunisia

Wood nanofibers from industrial waste have been used as polymeric material to reinforce the cement paste to a content of up to 2%by weight of *** effect of the wood nanofibre content on the porosity,the compressive strength and the degree of hydration of the cement was *** results showed an improvement in compressive strength of over 50%with 1%of added *** modification of nanofiber wood by grafting alkyl chains to their surface can reduce the amount of water absorbed by the *** of an anionic additive(SDBS)to the mixing water improves the surface of the samples more and more by minimizing the pore size by emulsion effect,hence the water absorption *** degree of hydration of the cement increased with the cellulose content containing *** analysis revealed that the presence of nanofibers favored the hydration of the cement by producing more calcium silicate gel and portlandite,probably the main reason for this improvement in compressive strength.

关键词： Cement nano-fiber wood modified adjuvant,surfactant emulsion

Effects of Cationic Surfactant on Fresh and Hardened Properties of Cement-Based Mortar

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Journal of Renewable Materials 2023年第5期11卷 2345-2365页

作者： Soumaya Zormati Fadhel Aloulou habib sammouda Laboratory of Energy and Materials LabEM-LR11ES34University of SousseSousseTunisia

The objective of this study is to analyze the effects of using surfactant(CTAB)and cellulose nanofibers(NFC)as an admixture in cement *** examined composite properties as porosity,compression energy,thermal conductivity and *** results showed that with the addition of 0.7%by weight of NFC per emulsion in the presence of a cationic surfactant(CTAB).The new material produced presented a dry porosity between 4.7%and 4.4%,compressive strength between 9.8 and 22.9 MPa,and thermal conductivity between 0.95 and 2.25 W·m^(−1)·K^(−1).Thus we show better mechanical and thermal performance than that traditional Portland cement mortar with a density *** addition,the mortar made by emulsion of ordinary portland cement,cellulose nanofiber and organophilic clay(OC)treated with cetyltrimethylammonium bromide(CTAB)obtained has good resistance under high temperature and water,as well as excellent thermal insulation performance under high temperature and humidity *** study verified that the presence of NFC promotes hydration,leading to the production of more calcium silicate and portlandite gel.

关键词： Cement nanofiber cellulose organophile-clay thermal conductivity hydration surfactant compressive strength mortar

Bio-PCM Panels Composed of Renewable Materials Interact with Solar Heating Systems for Building Thermal Insulation

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Journal of Renewable Materials 2024年第4期12卷 771-798页

作者： Yosr Laatiri habib sammouda Fadhel Aloulou Laboratory of Energy and Materials:LabEM-LR11ES34 University of SousseHammam SousseTunisia

This article aims to present the feasibility of storing thermal energy in buildings for solar water heating while maintaining the comfort environment for residential *** contribution is the creation of insulating composite panels made of bio-based phase change materials(bio-PCM is all from coconut oil),cement and renewable materials(treated wood fiber and organic clay).The inclusion of wood fibers improved the thermal properties;a simple 2%increase of wood fiber decreased the heat conductivity by approximately 23.42%.The issues of bio-PCM leakage in the cement mortar and a roughly 56.5%reduction in thermal conductivity with bio-PCM stability in composite panels can be resolved by treating wood fibers with an adjuvant by impregnating them in bio-PCM in the presence of the treated clay *** and wood fiber were treated with adjuvants that are both biological and environmentally acceptable,as confirmed by FTIR *** heat transfer bench(DIDATEK)showed a decrease in thermal *** using differential scanning calorimetric(DSC)analysis,the investigation of thermal stability and enthalpy during two heating cycles of pure bio-PCM and composite bio-PCM was *** novel renewable material was used to create composite panels for the trial prototype,which took the shape of a component attached to the solar heating system,33.57%less heat was lost,according to the heat transfer *** outcomes demonstrated the possibility of replacing traditional electric water heating in residential buildings with solar water heating systems.

关键词： Cement wood fiber PCM thermal conductivity thermal insulation solar energy

Some Advances in Applications of Lattice Boltzmann Method for Complex Thermal Flows

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Advances in Applied Mathematics and Mechanics 2010年第5期2卷 587-608页

作者： Ridha Djebali habib sammouda Mohammed El Ganaoui University of Tunis El-Manar FS of TunisDepartment of PhysicsLETTM1060 TunisTunisia CNRS/SPCTS UMR 6638FST of LimogesDepartment of Physics87060 LimogesFrance

Over the past two decades,there have been enormous advances in lattice Boltzmann(LB)numerical simulation and *** lattice Boltzmann method has become a practical and promising tool for many fluid problems.A majority of recent studies have relied on numerical computations of isothermal ***,much less efforts have been devoted to complex thermal flows,such as flows in porous media subjected to external magnetic force,flows with temperature-dependent *** this paper,an overview is made based on some accomplishments in these numerical *** with the paper’s sections,the state-of-the-art trend and the LBM advances in modelling and in computational aspects for specific classes of problems of major interest will be fully touched *** remarks are given and the axis of our future studies will be traced.

关键词： LB method Bifurcations and instability porous media flows plasma jets

Turbulent boundary layers and hydrodynamic flow analysis of nanofluids over a plate

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Journal of Central South University 2021年第11期28卷 3340-3353页

作者： AOUINET Hana DHAHRI Maher SAFAEI Mohammad Reza sammouda habib ANQI Ali E. Higher Private School of Engineering and Applied Technology(IHE-ESPITA) SousseTunisia Laboratory of Energy and Materials(LabEM)(LR11ES34) High School of Sciences and Technology of Hammam SousseSousse UniversityBP 4011Hammam SousseTunisia Department of Medical Research China Medical University HospitalChina Medical UniversityTaiwanChina Mechanical Engineering Department Faculty of EngineeringKing Abdulaziz UniversityJeddahSaudi Arabia Department of Mechanical Engineering College of EngineeringKing Khalid UniversityAbha 61421Saudi Arabia Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityAbhaSaudi Arabia

A numerical analysis of the log-law behavior for the turbulent boundary layer of a wall-bounded flow is performed over a flat plate immersed in three nanofluids(Zn O-water,SiO_(2)-water,TiO_(2)-water).Numerical simulations using CFD code are employed to investigate the boundary layer and the hydrodynamic *** validate the current numerical model,measurement points from published works were used,and the compared results were in good *** were carried out for the velocity series of 0.04,0.4 and 4 m/s and nanoparticle concentrations0.1% and 5%.The influence of nanoparticles’ concentration on velocity,temperature profiles,wall shear stress,and turbulent intensity was *** obtained results showed that the viscous sub-layer,the buffer layer,and the loglaw layer along the potential-flow layer could be analyzed based on their curving quality in the regions which have just a single wall *** was seen that the viscous sub-layer is the biggest area in comparison with other ***,the section where the temperature changes considerably correspond to the thermal boundary layer’s thickness goes a downward trend when the velocity *** thermal boundary layer gets deep away from the leading ***,a rise in the volume fraction of nanoparticles indicated a minor impact on the shear stress developed in the *** all cases,the thickness of the boundary layer undergoes a downward trend as the velocity increases,whereas increasing the nanoparticle concentrations would enhance the *** precisely,the log layer is closed with log law,and it is minimal between Y^(+)=50 and Y^(+)=*** temperature for nanoparticle concentration φ=5%is higher than that for φ=0.1%,in boundary layers,for all studied ***,it is established that the behavior is inverted from the value of Y^(+)=1 and the temperature for φ =0.1% is more important than the case of φ =5%.For turbulence intensity peak,this peak exists at Y^(+)

关键词： turbulent boundary layers nanofluids hydrodynamic flow wall shear stress turbulent intensity

Ru/NiMnB spherical cluster pillar for highly proficient green hydrogen electrocatalyst at high current density

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Journal of Energy Chemistry 2025年第1期100卷 397-408页

作者： Md Ahasan habib Shusen Lin Mehedi Hasan Joni Sumiya Akter Dristy Rutuja Mandavkar Jae-Hun Jeong Jihoon Lee Department of Electronic Engineering College of Electronics and Information Kwangwoon University

Advanced OER/HER electrocatalytic alternatives are crucial for the wide adaptation of green hydrogen ***,Ru/NiMnB spherical cluster pillar （SCP）,denoted as Ru/NiMnB,is synthesized using a combination of electro-deposition and hydrothermal *** investigation of Ru doping in the NiMnB matrix revealed significant improvements in electrocatalytic *** Ru/NiMnB SCPs demonstrate superior OER/HER activity with low overpotentials of 150 and 103 mV at 50mA/cm2in 1 M KOH,making them highly competitive with state-of-the-art ***,the Ru/NiMnB SCPs exhibit a low 2-E cell voltage of 2.80 V at ultra-high current density of 2,000 m A/cm2in 1 M KOH,outperforming the standard benchmark electrodes of RuO2||Pt/C,thereby positioning Ru/NiMnB as one of the best bifunctional *** SCPs exhibit exceptional high-current characteristics,stability and corrosion resistance,as evidenced by continuous operation at 1,000 mA/cm2high-current density for over 150 h in 6 M KOH at elevated temperatures under harsh industrial *** a small amount of Ru incorporation significantly enhances the electrocatalytic performances of NiMnB,attributed to increased active sites and improved intrinsic properties such as conductivity,adsorption/desorption capability and reaction ***,Ru/NiMnB SCPs present a promising bi-functional electrode concept for efficient green H2production.

关键词： Advanced electrocatalyst High current Corrosion resistance Industrial requirement

Pseudo-linear inertial navigation algorithm

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Chinese Journal of Aeronautics 2021年第2期34卷 191-200页

作者： habib GHANBARPOURASL Department of Mechcitronics University of Turkish Aeronautical AssociationAnkara 06790Turkey

A new method is illustrated for processing the output of a set of triad orthogonal rate gyros and accelerometers to reconstruct vehicle navigation parameters(attitude, velocity, and position). The paper introduces two vectors with dimensions 4×1 as velocity and position *** navigation equations for strapdown systems are nonlinear but after using these parameters, the navigation equations are converted into a pseudo-linear system. The new set of navigation equations has an analytical solution and the state transition matrix is used to solve the linear timevarying differential equations through time series. The navigation parameters are updated using the new formulation for strapdown navigation equations. Finally, the quaternions of velocity and position are converted into the original position and velocity vectors. The combination of the coning motion and a translational oscillatory trajectory is used to evaluate the accuracy of the proposed algorithm. The simulations show significant improvement in the accuracy of the inertial navigation system, which is achieved through the mentioned algorithm.

关键词： Inertial navigation algorithm Integrating algorithm Position quaternion Pseudo-linear inertial navigation equation Quaternions Velocity quaternion

Phylogenetic and morphometric relationships between two species of genus Auxis from the South China Sea and Java Sea

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Acta Oceanologica Sinica 2016年第10期35卷 76-82页

作者： habib Ahasan Environmental and Life Sciences Programme Faculty of ScienceUniversiti Brunei DarussalamJalan TungkuGadong BE 1410Brunei Darussalam Department of Fisheries and Marine Science Noakhali Science and Technology UniversitySonapur-3814NoakhaliBangladesh Universiti Teknologi Brunei Jalan TungkuGadong BE 1410Brunei Darussalam

This study was aimed at examining the phylogenetic and morphometric relationship of frigate tuna（Auxis thazard） and bullet tuna（Auxis rochei） using mt DNA D-loop（control） region sequences and truss measurements,respectively. Maximum-likelihood（ML） tree and median-joining network showed that haplotypes from Auxis populations grouped separately. Discriminant function analyses and non-metric multidimensional scaling of morphometric data showed that bullet and frigate tuna were differed mainly with respect to truss measurements on the anterior region, suggesting adaptation to different diets available in different environments. Historic demographic analyses of sequence data showed that both bullet and frigate tuna had not undergone a significant sudden population expansion recently. Non-significant value of Tajimas＇ s D and Fu＇s F_S were indicated an effective large and stable population size for longer period of both species in South China Sea and Java Sea species. This study gives first report on the complementary relationship between morphometric and genetic analysis in stock discrimination of genus Auxis.

关键词： phylogenetic relationship mtDNA D-loop morphometric analysis Auxis thazard Auxis rochei

A BOUNDARY INTEGRAL METHOD FOR COMPUTING ELASTIC MOMENT TENSORS FOR ELLIPSES AND ELLIPSOIDS

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Journal of Computational Mathematics 2007年第1期25卷 2-12页

作者： habib Ammari HyeonbaeKang HyundaeLee Centre de Mathématiques Appliquées CNRS UMR 7641 and Ecole Polytechnique91128 Palaiseau CedexFrance Department of Mathematical Sciences and RIM Seoul National UniversitySeoul 151-747Korea

The concept of elastic moment tensor occurs in several interesting contexts, in particular in imaging small elastic inclusions and in asymptotic models of dilute elastic composites. In this paper, we compute the elastic moment tensors for ellipses and ellipsoids by using a systematic method based on layer potentials. Our computations reveal an underlying elegant relation between the elastic moment tensors and the single layer potential.

关键词： Elastic moment tensor Explicit formulae Integral equations.