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Chinese Chemical Letters 2017年第1期28卷 75-82页

作者： Zahra Abbasi Sobhan Rezayati Maryam Bagheri Rahimeh Hajinasiri Young Researchers and Elite Club Ilam Branch Islamic Azad University Ilam Islamic Republic of Iron Chemistry Department Qaemshahr Branch Islamic Azad University PO BOX 163 Qaemshahr Islamic Republic of Iran

In this protocol, Ag supported on the hydroxyapatite-core–shell magnetic γ-Fe2O3nanoparticles（γFe2O3@HAp-Ag NPs） as a novel, efficient, and magnetically recyclable catalyst is synthesized, and characterized by transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, Fourier transform infrared spectroscopy（FT-IR）, X-ray diffraction（XRD）, and vibrating sample magnetometry（VSM）. The use of the catalyst is described in the synthesis of coumarin derivatives by the Pechmann condensation of various phenols with β-ketoesters under solvent- and halogen-free conditions at 80℃.This novel and inexpensive method offers advantages, such as recyclability simple experimental protocol, short reaction time, minimal work-up procedure, and excellent yields of products, together with desirable, eco-friendly, green aspects by avoiding toxic elements and solvents, and ease of recovery from the reaction mixture using an external magnet.

关键词： γ-Fe2O3 nanocatalyst Heterogeneous Catalyst Pechman condensation Ag supported

Physiological Responses of Zea mays Seedlings to Interactions Between Cadmium and Salinity

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Journal of Integrative Plant Biology 2006年第7期48卷 807-813页

作者： Mozhgan Farzami Sepehr Mahlagha Ghorbanli Department of Biology Faculty of Agriculture Islamic Azad University of Saveh Saveh Iran Department of Biology Islamic Azad University of Gorgan Gorgan Iran

The effects of 0, 2.5, 5.0, and 10.0 pmol/L Cd^2＋（Cd（NO3）2.4H2O） and 0, 10, 25, 50, and 100 mmol/L NaCl on growth, photosynthesis and the content of some ions in maize （Zea mays L.） were investigated in the present study. With Increasing concentrations of Cd^2＋ or NaCI alone in Hoagland nutrient solution, the chlorophylls and starch content decreased. Combination treatment with salinity and cadmium increased the negative effects observed following the two stresses alone. Plants exhibiting growth retardation in response to one mild stress factor （25-50 mmol/L NaCl） became more tolerant to the other stress factor （Cd）. The exposure of plants to cadmium caused a partial reversal of the effects of salinity. Root and shoot growth, ion accumulation and levels of photosynthetic pigments were improved at moderate concentrations of the two stress factors Imposed jointly.

关键词： cadmium content chlorophyll dry matter production growth rate ion accumulation salinity starch total soluble sugars Zea mays.

Synthesis and Infrared Spectra Computation of Sterically Congested 2,2-Disubstituted Indane-1,3-dione Derivatives

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Chinese Journal of Structural Chemistry 2011年第4期30卷 568-574页

作者： Seyed Mohammad Shoaei Ali Reza Kazemizadeh Ali Ramazani Department of Chemistry Islamic Azad UniversityZanjan Branch

Sterically congested 2,2-disubstituted indane-1,3-dione derivatives have been syn-thesized and characterized by 1H NMR,13C NMR,FT-IR and elemental *** B3LYP/HF calculations for computation of IR spectra have been carried out for the title compounds at the 6-31G and 6-311＋＋G basis set *** vibrational frequencies have been assigned and compared with the experimental FT-IR spectra and they are supported each other.

关键词： vibrational frequency DFT HF FT-IR spectra 2 2-disubstituted indane-1 3-dione isocyanide

DFT Study of the Mechanism and Regioselectivity of 1,3-Pentadiene with Methyl Acrylate Using Theoretical Approaches

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Chinese Journal of Structural Chemistry 2013年第2期32卷 243-251页

作者： Abolfazl Shiroudi Ehsan Zahedi Chemistry Department Shahrood Branch Islamic Azad University

Ab initio density functional theory （DFT） calculations have been used to study regioselectivity in the Diels-Alder （DA） cycloaddition reaction between 1,3-pentadiene and methyl acrylate. The DFT calculations were performed with the B3LYP functional and 6-31 1＋G^＊＊ basis set. Two synchronous transition structures corresponding to the formation of different regioisomers associated with the two reaction channels have been located. The DFT calculations generated transition geometries with a very small degree of asynchronicity. The present analysis shows that these reactions have normal electron demand （NED） character. Moreover, the results obtained from energetic and electronic approaches with the exception of Houk＇s rule confirm that ortho regioisomer is the major product.

关键词： ab initio DFT NBO Diels-Alder cycloaddition transition states

Effects of the deep rolling process on the surface roughness and properties of an Al-3vol%SiC nanoparticle nanocomposite fabricated by mechanical milling and hot extrusion

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International Journal of Minerals,Metallurgy and Materials 2017年第7期24卷 814-825页

作者： Sajjad Sattari Amir Atrian Department of Mechanical Engineering Najafabad Branch Islamic Azad University Najafabad Iran Modem Manufacturing Technologies Research Center Najafabad Branch Islamic Azad University Najafabad lran

Deep rolling is one of the most widely used surface mechanical treatments among several methods used to generate compressive residual stress. This process is usually used for axisymmetric components and can lead to improvements of the surface quality, dimensional accuracy, and mechanical properties. In this study, we deduced the appropriate deep rolling parameters for Al-3vol%Si C nanocomposite samples using roughness and microhardness measurements. The nanocomposite samples were fabricated using a combination of mechanical milling, cold pressing, and hot extrusion techniques. Density measurements indicated acceptable densification of the samples, with no porosity. The results of tensile tests showed that the samples are sufficiently strong for the deep rolling process and also indicated near 50% improvement of tensile strength after incorporating Si C nanoparticle reinforcements. The effects of some important rolling parameters, including the penetration depth, rotation speed, feed rate, and the number of passes, on the surface quality and microhardness were also investigated. The results demonstrated that decreasing the feed rate and increasing the number of passes can lead to greater surface hardness and lower surface roughness.

关键词： deep rolling nanocomposite mechanical milling hot extrusion roughness hardness

Thermal Decomposition Kinetics of Ethane Halides and Derivatives(C_2H_(6-n)X_n(n = 1～3);X = F,Cl,Br):DFT Study and NBO Analysis

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Chinese Journal of Structural Chemistry 2011年第6期30卷 858-866页

作者： Abolfazl Shiroudi Ehsan Zahedi Chemistry Department Islamic Azad UniversityShahrood Branch

A theoretical study of the thermal decomposition kinetics of ethane halides（C2H6-nXn（n = 1～3）;X = F,Cl,Br） has been carried out at the B3LYP/6-31＋＋G＊＊ and B3PW91/631＋＋G＊＊ levels of *** these methods and comparison of activation parameters with available experimental values,the B3PW91/6-31＋＋G＊＊ method is in good agreement with the experimental *** analysis of bond order and natural bond orbital（NBO） charges,bond indexes,and synchronicity parameters suggest the elimination of HX in reactions 1～9（HF：compounds 1～3,HCl：compounds 4～6,and HBr：compounds 7～9） occur through a concerted and slightly asynchronous four-membered cyclic transition state type of mechanism.

关键词： elimination ab initio molecular modeling decomposition ethane halides NBO

Level-direction decomposition analysis with a focus on image watermarking framework

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Frontiers of Information Technology & Electronic Engineering 2016年第11期17卷 1199-1217页

作者： M.F.KAZEMI M.A.POURMINA A.H.MAZINAN Department of Electrical and Computer Engineering Science and Research Branch Islamic Azad University Department of Control Engineering Faculty of Electrical Engineering South Tehran Branch Islamic Azad University

This research addresses the new level-direction decomposition in the area of image watermarking as the further development of investigations. The main process of realizing a watermarking framework is to generate a watermarked image with a focus on contourlet embedding representation. The approach performance is evaluated through several indices including the peak signal-to-noise ratio and structural similarity, whereby a set of attacks are carried out using a module of simulated attacks. The obtained information is analyzed through a set of images, using different color models, to enable the calculation of normal correlation. The module of the inverse of contourlet embedding representation is correspondingly employed to obtain the present watermarked image, as long as a number of original images are applied to a scrambling module, to represent the information in disorder. This allows us to evaluate the performance of the proposed approach by analyzing a complicated system, where a decision making system is designed to find the best level and the corresponding direction regarding contourlet embedding representation. The results are illustrated in appropriate level-direction decomposition. The key contribution lies in using a new integration of a set of subsystems, employed based upon the novel mechanism in contourlet embedding representation, in association with the decision making system. The presented approach is efficient compared with state-of-the-art approaches, under a number of serious attacks. A number of benchmarks are obtained and considered along with the proposed framework outcomes. The results support our ideas.

关键词： Level-direction decomposition analysis Watermarking framework Contourlet embedding representation Scrambling module Simulated attacks

Solving the Task Starvation and Resources Problem Using Optimized SMPIA in Cloud

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Computer Systems Science & Engineering 2022年第8期42卷 659-675页

作者： Mehran Mokhtari Homayun Motameni Peyman Bayat Department of Computer Sari BranchIslamic Azad UniversitySariIran Department of Computer Rasht BranchIslamic Azad UniversityRashtIran

In this study,a new feature is added to the smart message passing interface(SMPI)approach(SMPIA)based on the prioritization method,which cancompletely eliminate the task starvation and lack of sufficient resources problemsthrough prioritizing the *** proposed approach is based on prioritizing thetasks and the urgency of *** are prioritized based on executiontime,workload,the task with a more sensitive priority is executed earlier by thefree *** idea of demand-bound functions(DBFs)was extended to theSMPIA setting based on partitions and *** each task,two DBFs are constructed,DBFLO and DBFHI,for the LO and HI criticality modes,*** simulation results returned by MATLAB showed that with the optimizedSMPIA(O-SMPIA),the parameters of maximum service execution time,response time,delay time,and throughput improved in this *** addition,the results confirmed that the reduction of execution time,completion time,andresource consumption time did not affect the response time and throughput ofworkflow tasks and did not cause inefficient use of resources in virtual machines(VMs)and data centers(DCs).The evaluation of performance metrics showedthat the delay,response time of the Greedy algorithm was less than that ofMax-Min and *** the same time,the execution time of Max-Min wasless than the others and the throughput of the Greedy was *** effectand throughput of O-SMPIA became more obvious as change to the job countand the number of cloud workloads *** is also worth mentioning thatone of the main advantages of the O-SMPIA to other methods is the efficientuse of time to execute all the defined tasks by CPU.

关键词： Cloud computing O-SMPIA task starvation EDF-VD

NBO/NMR Analysis of Interaction between Picene and Boron Nitrid Nano Ring

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Chinese Journal of Structural Chemistry 2019年第7期38卷 1116-1122页

作者： MEHRNOOSH Khaleghian Department of Chemistry Islamshahr BranchIslamic Azad University

In order to investigate the non-bonded interaction between picene and B12 N12 nano ring(BNNR) in different orientations and distances, we focused on a single-wall boronnitride B12 N12 nano-ring. The geometry of molecules was optimized using the B3 LYP method with 6-31 g* basis set. The reactivity and stability of picene as an aromatic compound alone and upon exposure to BNNR were checked. Then NBO, FREQ, NICS and adsorption energy of picene alone and in the presence of BNNR Field were derived to estimate the picene structural *** results of any order were found to reduce the reactivity and increase the stability for picene in the presence BNNR field.

关键词： picene DFT Freq NBO NICS

Optimal operation of energy at hydrothermal power plants by simultaneous minimization of pollution and costs using improved ABC algorithm

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Frontiers in Energy 2015年第4期9卷 426-432页

作者： Homayoun EBRAHIMIAN Bahman TAHERI Nasser YOUSEFI Department of Engineering Ardabil Branch Islamic Azad University Ardabil 0451 Iran Young Researchers and Elite Club Ardabil Branch Islamic Azad University Ardabil 0451 Iran

The aim of this paper is simultaneous mini- mization of hydrothermal units to reach the best solution by employing an improved artificial bee colony （ABC） algorithm in a multi-objective function consisting of economic dispatch （ED） considering the valve-point effect and pollution function in power systems in view of the hot water of the hydro system. In this type of optimization problem, all practical constraints of units were taken into account as much as possible in order to comply with the reality. These constraints include the maximum and minimum output power of units, the constraints caused by the balance between supply and demand, the impact of pollution, water balance, uneven production curve con- sidering the valve-point effect and system losses. The proposed algorithm is applied on the studied system, and the obtained results indifferent operating conditions are analyzed. To investigate in various operating conditions, different load profiles in 12 h are taken into account. The obtained results are compared with those of the other methods including the genetfc algorithm （GA）, the Basu technique, and the improved genetic algorithm. Fast convergence is one of this improved algorithm features.

关键词： practical constraints of units pollution func-tion inlet steam valve up-ramp rate of units improvedABC algorithm