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Synthesis of Poly(acrylic acid)-Grafted Carboxymethyl Cellulose for Efficient Removal of Copper Ions

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Journal of Renewable Materials 2019年第12期7卷 1403-1414页

作者： Ying Lin Yihua Cao Qingping Song Jiangang Gao Puyou Jia hamed alsulami Marwan Amin Kutbi College of Biological and Chemical Engineering Anhui Polytechnic UniversityWuhu241000China Institute of Chemical Industry of Forest Products Chinese Academy of Forestry(CAF)Nanjing210042China Department of Mathematics Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia.

Biocompatible and high content grafted carboxymethyl cellulose-g-poly(acrylic acid)powder was successfully synthesized in an aqueous system,and used as adsorbents for the removal of Cu(II)in aqueous *** copolymer was characterized by FT-IR and SEM *** copolymerization introduced a large number of carboxyl groups in the polymer and caused the micro-surface of the material to be *** fundamental adsorption behaviors of the material were *** adsorption kinetics was well fitted with pseudo-second order equation,while the adsorption isotherm preferred to be described the Langmuir *** maximum adsorption capacity obtained from the Langmuir model was 154.32 mg/g,indicating that the adsorption capacity of carboxymethyl cellulose was improved remarkably after grafting poly(acrylic acid).Moreover,Fourier transform infrared spectroscopy(FT-IR)has been used to investigate the adsorption mechanisms at molecular levels,which revealed that carboxyl groups are facile to form bidentate carboxylates with metal ***,this environment friendly copolymer will be a promising candidate for application in removal of heavy metal ions.

关键词： Carboxymethyl cellulose-g-acrylic acid grafting copolymerization adsorption copper ions

Modal interactions in primary and subharmonic resonant dynamics of imperfect microplates with geometric nonlinearities

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Acta Mechanica Sinica 2016年第3期32卷 469-480页

作者： hamed Farokhi Mergen h.Ghayesh Department of Mechanical Engineering McGill University School of Mechanical Materials and MechatronicEngineering University of Wollongong

This paper analyses the modal interactions in the nonlinear, size-dependent dynamics of geometrically imperfect microplates. Based on the modified couple stress theory,the equations of motion for the in-plane and out-of-plane motions are obtained employing the von Kármán plate theory as well as Kirchhoff＇s hypotheses by means of the Lagrange equations. The equations of motions are solved using the pseudo-arclength continuation technique and direct timeintegration method. The system parameters are tuned to the values associated with modal interactions, and then nonlinear resonant responses and energy transfer are *** motion characteristics are shown in the form of frequency-response and force-response curves, time histories, phase-plane portraits, and fast Fourier transforms.

关键词： Modal interactions Microplate Sizedependent dynamics Modified couple stress theory Stability

Task Scheduling Optimization in Cloud Computing Based on Genetic Algorithms

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Computers, Materials & Continua 2021年第12期69卷 3289-3301页

作者： Ahmed Y.hamed Monagi h.Alkinani Faculty of Computers and Information Department of Computer ScienceSohag UniversitySohag82524Egypt Department of Computer Science and Artificial Intelligence College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia

Task scheduling is the main problem in cloud computing that reduces system performance;it is an important way to arrange user needs and perform multiple *** computing is the most popular technology nowadays and has many research potential in various areas like resource allocation,task scheduling,security,privacy,*** improve system performance,an efficient task-scheduling algorithm is *** task-scheduling algorithms focus on task-resource requirements,CPU memory,execution time,and execution *** this paper,a task scheduling algorithm based on a Genetic Algorithm(GA)has been presented for assigning and executing different *** proposed algorithm aims to minimize both the completion time and execution cost of tasks and maximize resource *** evaluate our algorithm’s performance by applying it to two examples with a different number of tasks and *** first example contains ten tasks and four processors;the computation costs are generated *** last example has eight processors,and the number of tasks ranges from twenty to seventy;the computation cost of each task on different processors is generated *** achieved results show that the proposed approach significantly succeeded in finding the optimal solutions for the three objectives;completion time,execution cost,and resource utilization.

关键词： Cloud computing task scheduling genetic algorithm optimization algorithm

Drill bit wear monitoring and failure prediction for mining automation

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International Journal of Mining Science and Technology 2023年第3期33卷 289-296页

作者： hamed Rafezi Ferri hassani Department of Mining and Materials Engineering McGill UniversityMontreal H3A 0G4Canada

This article introduces a novel approach for tricone bit wear condition monitoring and failure prediction for surface mining applications.A successful bit health monitoring system is essential to achieve fully autonomous blasthole *** this research in-situ vibration signals were analyzed in timefrequency domain and signals trend during tricone bit life span were investigated and introduced to support the development of artificial intelligence(AI)*** addition to the signal statistical features,wavelet packet energy distribution proved to be a powerful indicator for bit wear *** artificial neural network(ANN)models were designed,trained and evaluated for bit state ***,an ANN architecture and feature vector were introduced to classify the bit condition and predict the bit failure.

关键词： Drilling vibration Condition monitoring Failure prediction Bit wear Wavelet energy Mining automation

Drilling signals analysis for tricone bit condition monitoring

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International Journal of Mining Science and Technology 2021年第2期31卷 187-195页

作者： hamed Rafezi Ferri hassani Department of Mining and Materials Engineering McGill UniversityMontreal H3A 0G4Canada

This paper presents a novel approach to investigate the relations between drilling signals and bit wear condition in real world full-scale mining *** research addresses the increasing demand for automation in mining to increase the efficiency,safety,and ability to work in harsh environments.A crucial issue in fully autonomous unmanned drilling is to have a system to detect the bit wear condition through the drilling signals analysis in real *** this work,based on extensive field studies,a novel qualitative method for tricone bit wear state classification is developed and *** relations between drilling vibration as well as electric motor current signals and bit wear are investigated and bit failure vibration frequencies,regardless of the geological conditions,are *** failure frequencies are experimentally investigated and analytically ***,the effect of bit design parameters on the failure frequencies is presented for the application of bit wear condition monitoring and bit failure prediction.

关键词： Drilling Tricone bit Vibration Wear Condition monitoring Failure prediction

Resilient modulus prediction of soft low-plasticity Piedmont residual soil using dynamic cone penetrometer

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 323-332页

作者： S.hamed Mousavi Mohammed A.Gabr Roy h.Borden Department of Civil Construction and Environmental Engineering North Carolina State University

Dynamic cone penetrometer（DCP） has been used for decades to estimate the shear strength and stiffness properties of the subgrade soils. There are several empirical correlations in the literature to predict the resilient modulus values at only a specific stress state from DCP data, corresponding to the predefined thicknesses of pavement layers（a 50 mm asphalt wearing course, a 100 mm asphalt binder course and a200 mm aggregate base course）. In this study, field-measured DCP data were utilized to estimate the resilient modulus of low-plasticity subgrade Piedmont residual soil. Piedmont residual soils are in-place weathered soils from igneous and metamorphic rocks, as opposed to transported or compacted *** the existing empirical correlations might not be applicable for these soils. An experimental program was conducted incorporating field DCP and laboratory resilient modulus tests on "undisturbed" soil specimens. The DCP tests were carried out at various locations in four test sections to evaluate subgrade stiffness variation laterally and with depth. Laboratory resilient modulus test results were analyzed in the context of the mechanistic-empirical pavement design guide（MEPDG） recommended universal constitutive model. A new approach for predicting the resilient modulus from DCP by estimating MEPDG constitutive model coefficients（k;,k;and k;） was developed through statistical analyses. The new model is capable of not only taking into account the in situ soil condition on the basis of field measurements,but also representing the resilient modulus at any stress state which addresses a limitation with existing empirical DCP models and its applicability for a specific case. Validation of the model is demonstrated by using data that were not used for model development, as well as data reported in the literature.

关键词： Dynamic cone penetrometer(DCP) Resilient modulus Mechanistic-empirical pavement design guide(MEPDG) Residual soils Subgrade soils

Ant Colony Optimization for Multi-Objective Multicast Routing

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Computers, Materials & Continua 2020年第6期63卷 1159-1173页

作者： Ahmed Y.hamed Monagi h.Alkinani M.R.hassan Department of Computer Science Faculty of Computers and InformationSohag UniversitySohag82524Egypt Department of Computer Science and Artificial Intelligence College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia Department of Mathematics and Computer Science Faculty of ScienceAswan UniversityAswan81528Egypt

In the distributed networks,many applications send information from a source node to multiple destination *** support these applications requirements,the paper presents a multi-objective algorithm based on ant colonies to construct a multicast tree for data transmission in a computer *** proposed algorithm simultaneously optimizes total weight(cost,delay and hop)of the multicast *** results prove the proposed algorithm outperforms a recently published Multi-objective Multicast Algorithm specially designed for solving the multicast routing ***,it is able to find a better solution with fast convergence speed and high reliability.

关键词： Multimedia communication multicast routing multicast tree quality of service ant colony

A Genetic Algorithm to Solve Capacity Assignment Problem in a Flow Network

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Computers, Materials & Continua 2020年第9期64卷 1579-1586页

Computer networks and power transmission networks are treated as capacitated flow networks.A capacitated flow network may partially fail due to ***,the capacity of each edge should be optimally assigned to face critical situations-i.e.,to keep the network functioning normally in the case of failure at one or more *** robust design problem(RDP)in a capacitated flow network is to search for the minimum capacity assignment of each edge such that the network still survived even under the edge’s *** RDP is known as ***,capacity assignment problem subject to system reliability and total capacity constraints is studied in this *** problem is formulated mathematically,and a genetic algorithm is proposed to determine the optimal *** optimal solution found by the proposed algorithm is characterized by maximum reliability and minimum total *** numerical examples are presented to illustrate the efficiency of the proposed approach.

关键词： Flow network capacity assignment network reliability genetic algorithms

Synthesis and characterization of carbon-coated cobalt ferrite nanoparticles

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1104-1111页

作者： hamed Bakhshi Ali Shokuhfar Nima Vahdati Advanced Materials and Nanotechnology Lab Department of Materials Science and Engineering K.N.Toosi University of Technology Department of Materials Science and Engineering Saveh Branch Islamic Azad University

Cobalt ferrite nanoparticles（CFNPs） were prepared via a reverse micelle method. The CFNPs were subsequently coated with carbon shells by means of thermal chemical vapor deposition（TCVD）. In this process, acetylene gas（C2h2） was used as a carbon source and the coating was carried out for 1, 2, or 3 h at 750℃. The Ar/C2h2 ratio was 10：1. heating during the TCVD process resulted in a NP core size that approached 30 nm; the thickness of the shell was less than 10 nm. The composition, structure, and morphology of the fabricated composites were characterized using X-ray diffraction, simultaneous thermal analysis, transmission electron microscopy, high-resolution transmission electron microscopy, and selected-area diffraction. A vibrating sample magnetometer was used to survey the samples＇ magnetic properties. The deposited carbon shell substantially affected the growth and magnetic properties of the CFNPs. Micro-Raman spectroscopy was used to study the carbon coating and revealed that the deposited carbon comprised graphite, multiwalled carbon nanotubes, and diamond-like carbon. With an increase in coating time, the intensity ratio between the amorphous and ordered peaks in the Raman spectra decreased, which indicated an increase in crystallite size.

关键词： nanoparticles cobalt ferrite carbon coatings chemical vapor deposition Raman spectroscopy