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Green bio-synthesis of Ni/montmorillonite nanocomposite using extract of Allium jesdianum as the nano-catalyst for electrocatalytic oxidation of methanol

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2555-2565页

作者： Mohammad Hossein Sheikh-Mohseni Sajjad Sedaghat Pirouz Derakhshi Aliakbar Safekordi Department of Chemistry Science and Research BranchIslamic Azad UniversityTehranIran Department of Chemistry Shahr-e-Qods BranchIslamic Azad UniversityShahr-e-QodsIran Department of Chemistry North Tehran BranchIslamic Azad UniversityTehranIran

In this work,synthesis of Ni nanoparticles was carried out successfully by water extract of Allium jesdianum as a biochemical reducing agent in the presence of montmorillonite clay(MMT)as a natural solid support for the first *** the electrochemical activity of the synthesized nanocomposite was investigated in methanol electrocatalytic *** with high cation exchange capacity and nano layer structure was exposed to ion exchange conditions in nickel *** Ni^2+ion exchanged form was used in this process as a source of ions and also capping *** extract of Allium jesdianum used as a reducing agent due to abundant availability of phenolic and flavonoid *** synthesized Ni/MMT nanocomposite was characterized using UV–Vis spectroscopy(UV–Vis),Fourier Transform Infrared Spectroscopy(FT-IR),X-ray diffraction(XRD),Scanning Electron Microscopy(SEM),Transmission electron microscopy(TEM)and Energy-dispersive X-ray spectroscopy(EDX).The surface of prepared modified electrode has been characterized using SEM to evaluate the morphology,showing uniform dispersion of Ni nanoparticles with mean diameter of 12 to 20 *** modified carbon paste electrode was then used in methanol electrocatalytic oxidation *** oxidation on the proposed modified electrode surface occurs at 0.6 V and 0.3 V in alkaline and acidic medium ***,the results showed the better performance of modified electrode toward methanol electrocatalytic oxidation in comparison with carbon paste electrode that is modified by ion exchanged *** transfer coefficients and apparent charge transfer rate constant for the modified electrode in the absence of methanol in alkaline medium were respectively found as:αa=0.53,αc=0.37 and ks=1.6×10^-1 s^-***,the average value of catalytic rate constant for the electrocatalytic oxidation of methanol by the prepared nano-catalyst was estimated to be about 0.9 L·mol^-1·s^-1 by chronoamperometry *** prepare

关键词： Green biosynthesis Nanoparticles Montmorillonite Biocatalysis Methanol electrocatalytic oxidation Fuel cell

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Maximizing the Absorbed Power of A Point Absorber Using An FA-Based Optimized Model Predictive Control

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China Ocean Engineering 2018年第6期32卷 696-705页

作者： Negar RAHIMI Reihaneh Kardehi MOGHADDAM Department of Electrical Engineering Mashhad Branch Islamic Azad University

This paper presents an extended model predictive controller for maximizing the absorbed power of a point absorber wave energy converter. Owing to the great influence of controller parameters upon the absorbed power, the optimization of these parameters is carried out for the first time by a firefly algorithm(FA). Error, the difference between output velocity of buoy and input wave speed which leads to power maximization in the optimized MPC is compared with the classical MPC. Simulation results indicate that given the high accuracy and acceptable speed of the algorithm, it can adjust the parameters of the controller to the point where system error decreased effectively and the absorbed energy increased about 4 MW.

关键词： wave energy point absorber predictive controller firefly algorithm

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Properties of Defect Modes in Periodic Lossy Multilayer with Negative-Index-Materials

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Communications in Theoretical Physics 2013年第7期60卷 80-86页

作者： Alireza Aghajamal Mahmood Barati Department of Physics Science and Research Branch Islamic Azad University Young Researchers Club Science and Research Branch Islamic Azad University

Employing the characteristic matrix method, this study investigates transmission properties of onedimensional defective lossy photonic crystals composed of negative and positive refractive index layers with one lossless defect layer at the center of the crystal. The results of the study show that as the refractive index and thickness of the defect layer increase, the frequency of the defect mode decreases. In addition, the study shows that the frequency of the defect mode is sensitive to the incidence angle, polarization, and physical properties of the defect layer, but it is insensitive to the small lattice loss factor. The peak of the defect mode is very sensitive to the loss factor, incidence angle, polarization, refractive index, and thickness of the defect layer. This study also shows that the peak and the width of the defect mode are affected by the numbers of the lattice period and the loss factor. The results can lead to designing new types of narrow filter structures and other optical devices.

关键词： one-dimensional photonic crystal defect mode loss factor negative index material

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An Improved Binary Quantum-based Avian Navigation Optimizer Algorithm to Select Effective Feature Subset from Medical Data:A COVID-19 Case Study

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Journal of Bionic Engineering 2024年第1期21卷 426-446页

作者： Ali Fatahi Mohammad H.Nadimi-Shahraki Hoda Zamani Faculty of Computer Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Big Data Research Center Najafabad BranchIslamic Azad UniversityNajafabad ***Iran

Feature Subset Selection(FSS)is an NP-hard problem to remove redundant and irrelevant features particularly from medical data,and it can be effectively addressed by metaheuristic ***,existing binary versions of metaheuristic algorithms have issues with convergence and lack an effective binarization method,resulting in suboptimal solutions that hinder diagnosis and prediction *** paper aims to propose an Improved Binary Quantum-based Avian Navigation Optimizer Algorithm(IBQANA)for FSS in medical data preprocessing to address the suboptimal solutions arising from binary versions of metaheuristic *** proposed IBQANA’s contributions include the Hybrid Binary Operator(HBO)and the Distance-based Binary Search Strategy(DBSS).HBO is designed to convert continuous values into binary solutions,even for values outside the[0,1]range,ensuring accurate binary *** the other hand,DBSS is a two-phase search strategy that enhances the performance of inferior search agents and accelerates *** combining exploration and exploitation phases based on an adaptive probability function,DBSS effectively avoids local *** effectiveness of applying HBO is compared with five transfer function families and thresholding on 12 medical datasets,with feature numbers ranging from 8 to 10,***'s effectiveness is evaluated regarding the accuracy,fitness,and selected features and compared with seven binary metaheuristic ***,IBQANA is utilized to detect *** results reveal that the proposed IBQANA outperforms all comparative algorithms on COVID-19 and 11 other medical *** proposed method presents a promising solution to the FSS problem in medical data preprocessing.

关键词： Feature subset selection Optimization Binary metaheuristic algorithms Bioinspired Machine learning Medical datasets

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Calculation of Half-Metal, Debye and Curie Temperatures of Co_2 VAl Compound: First Principles Study

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Communications in Theoretical Physics 2015年第5期63卷 641-647页

作者： Arash Boochani Heidar Khosravi Jabbar Khodadadi Shahram Solaymani Masoud Majidiyan Sarmazdeh Rohollah Taghavi Mendi Sayed Mohammad Elahi Department of Physics Kermanshah Branch Islamic Azad University Young Researchers and Elite club Kermanshah Branch Islamic Azad University Department of Physics Payame Noor University Department of Physics Mashhad Branch Islamic Azad University

By FP-LAPW calculations, the structural, elastic, Debye and Curie temperatures, electronic and magnetic properties of Co2 VAl are investigated. The results indicate that Ferromagnetic （FM） phase is more stable than Anti- Ferromagnetic （AFM） and Non-magnetic （NM） ones. In addition, C11-C12 〉 0, C44 〉 0, and B 〉 0 so Co2 VAl is an elastically stable material with high Debye temperature. Also, the BIG ratio exhibits a ductility behavior. The relatively high Curie temperature provides it as a favorable material for spintronic application. It＇s electronic and magnetic properties are studied by GGA ＋U approach leading to a 100% spin polarization at Fermi level.

关键词： exchange energy Debye temperature Curie temperature Co2VAl GGA+U

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An Effective Hybridization of Quantum-based Avian Navigation and Bonobo Optimizers to Solve Numerical and Mechanical Engineering Problems

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Journal of Bionic Engineering 2023年第3期20卷 1361-1385页

作者： Mohammad H.Nadimi-Shahraki Faculty of Computer Engineering Najafabad BranchIslamic Azad UniversityNajafabad***Iran Big Data Research Center Najafabad BranchIslamic Azad UniversityNajafabad***Iran

Hybrid metaheuristic algorithms play a prominent role in improving algorithms' searchability by combining each algorithm's advantages and minimizing any substantial shortcomings. The Quantum-based Avian Navigation Optimizer Algorithm (QANA) is a recent metaheuristic algorithm inspired by the navigation behavior of migratory birds. Different experimental results show that QANA is a competitive and applicable algorithm in different optimization fields. However, it suffers from shortcomings such as low solution quality and premature convergence when tackling some complex problems. Therefore, instead of proposing a new algorithm to solve these weaknesses, we use the advantages of the bonobo optimizer to improve global search capability and mitigate premature convergence of the original QANA. The effectiveness of the proposed Hybrid Quantum-based Avian Navigation Optimizer Algorithm (HQANA) is assessed on 29 test functions of the CEC 2018 benchmark test suite with different dimensions, 30, 50, and 100. The results are then statistically investigated by the Friedman test and compared with the results of eight well-known optimization algorithms, including PSO, KH, GWO, WOA, CSA, HOA, BO, and QANA. Ultimately, five constrained engineering optimization problems from the latest test suite, CEC 2020 are used to assess the applicability of HQANA to solve complex real-world engineering optimization problems. The experimental and statistical findings prove that the proposed HQANA algorithm is superior to the comparative algorithms.

关键词： Optimization Metaheuristic algorithms Evolutionary algorithm Quantum-based avian navigation optimizer algorithm Engineering optimization problems,Bionic algorithm

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Surface plasmon resonance and electrical properties of RF: magnetron sputtered carbon–nickel composite films at different annealing temperatures

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Rare Metals 2016年第11期35卷 863-869页

作者： Vali Dalouji S.Mohammad Elahi Sirvan Naderi Department of Physics Malayer University Plasma Physics Research Center Science and Research BranchIslamic Azad University Department of Physics Kermanshah BranchIslamic Azad University

In this work, the optical absorption spectra of carbon-nickel films annealed at different temperatures（300-1000 ℃） with a special emphasis on the surface plasmon resonance（SPR） were investigated. The films were grown on quartz substrates by radio-frequency（RF）magnetron co-sputtering at room temperature with a deposition time of 600 s. The optical absorption peaks due to the SPR of Ni particle are observed in the wavelength range of 300-330 nm. With annealing temperature increasing up to 500 ℃ due to the increase in Ni particle size, the intensity of the SPR peaks increases, but weakens with annealing temperature increasing over 500 ℃. The Ni nanoparticle size, the dielectric function of carbon matrix（ε_m） and the plasma frequency of the free electrons（ω_p） at500 ℃have the maximum values of 21.63 nm, 0.471 and5.26 9 10^（15）s^（-1）, respectively. The absorption peak shows a redshift trend up to 500 ℃and then turn to blueshift with annealing temperature increasing over 500 ℃ These observations are in a good agreement with the electrical measurements in temperature range of 15-520 K and the Maxwell-Garnett（M-G） effective medium theory（EMT）.

关键词： Surface plasmon resonance Carbon-nickelfilms Ni content Annealing temperatures Electricalresistivity

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Acetone Adsorption on Pristine and Pt-doped Graphene:A First-Principles vdW-DF Study

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Communications in Theoretical Physics 2015年第11期64卷 576-582页

作者： Masoud Darvish Ganji Hoda Mazaheri azadeh Khosravi Department of Nanochemistry Faculty of Pharmaceutical Chemistry Pharmaceutical Sciences BranchIslamic Azad University Department of Chemistry Qaemshahr BranchIslamic Azad University Young Researchers and Elite Club Central Tehran BranchIslamic Azad University

Using van der Waals corrected density functional theory(vdW-DF) method we have investigated the adsorption of acetone molecule on pristine and Pt-doped *** active sites for both the interacting systems have been considered in the adsorption process including full geometry *** have analyzed the structural and electrical properties of energetically favorable *** results show that adsorption of acetone molecule on the Pt-doped graphene is energetically *** binding energy and bonding distance are determined to be-5.277 eV and 2.206 A,respectively,accompanying with charge transfer of 1.11 ***,the Pt-0 bond is rather significantly elongated when acetone is adsorbed on Pt-doped *** to pristine graphene,the Pt-doped graphene has stronger interaction with the acetone and may provide more sensitive signai for a single acetone ***,practically,the band gap of Pt-doped graphene would become reduced after acetone ***,our first-principles study presents evidence for a coherent benchmark for the applicability of Pt-doped graphene for acetone adsorption and detection.

关键词： Pt-doped graphene acetone ab initio calculations s

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Scattering States of Schrdinger Equation under the Modified Cusp Potential

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Communications in Theoretical Physics 2013年第7期60卷 25-27页

作者： Z. Molaee H. Hassanabadi S. Zarrinkamar Department of Basic Sciences Garmsar Branch Islamic Azad University Department of Basic Sciences Shahrood Branch Islamic Azad University

We solve the one-dimensionai time-independent Schrodinger equation in the presence of the modified Cusp potential and report the solutions in terms of the Whittaker functions. We obtain the reflection and transmission coefficients as well as the bound-state solutions in terms of the Whittaker functions. We comment on the solutions and discuss them in terms of the engaged parameters.

关键词： Schrodinger equation Whittaker functions reflection coefficient transmission coefficient bound-state solutions

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Simulation and optimization of an industrial gas condensate stabilization unit to modify LPG and NGL production with minimizing CO2 emission to the environment

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Chinese Journal of Chemical Engineering 2017年第3期25卷 338-346页

作者： M.Bahmani J.Shariati A.Nemati Rouzbahani Young Researchers and Elite Club Darab BranchIslamic Azad UniversityDarabIran Department of Chemical Engineering Darab BranchIslamic Azad UniversityDarabIran

In the present study, a great effort was made to improve the performance of an industrial liquefied petroleum gas(LPG) and natural gas liquid(NGL) production unit in one of the major gas refinery located at Pars special economic zone in Iran. To demonstrate and obtain the optimal condition, the unit was simulated by using a steady-state flowsheet simulator, i.e. Aspen Plus, under different operational conditions. According to the simulation results,the unit was not operational under its optimal conditions due to some defects in the cooling system at top stage of the debutanizer tower(DBT) during hot and humid seasons. Additionally, the vapor pressure of produced LPG and accordingly the amount of its flaring were decreased by reducing the temperature of debutanizer tower at top stages. In the optimization section, the DBT condenser and reboiler heat duty, temperature, and pressure were regulated as adjustable parameters. The simulation results demonstrated that by applying the optimum suggestion in the hot months, the reflux stream temperature was reached about 55 ℃ which caused an efficient increment in LPG production(about 4%) with adjusting the propane component in LPG, based on the standard range as the plant criteria. Moreover, after applying modifications, about 750 t of LPG product was saved from flaring during five hot months of the year, which resulted in 360000 USD extra annual income for the ***, from environmental point of view, this optimization caused to reduce 81 t of CO_2 emission to the environment. Therefore, the current investigation must be introduced as a friendly environmentally process.

关键词： LPG NGL Simulation Optimization CO2 emission

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