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燃料化学学报 2015年第2期43卷 195-201页

作者： Maedeh Enayati hossein Faghihian Department of Chemistry Shahreza BranchIslamic Azad University

In this research,1-butyl-pyridinium tetrafluoroborate([C4Py][BF4]-)was prepared by ion exchange method and was characterized by1H-NM R,13C-NM R,and FT-IR *** synthesized ionic liquid w as used for removal of dibenzothiophene as a typical organosulfur pollutant from organic *** effect of different parameters on the extraction efficiency w as studied and *** the optimized conditions,97.68%of dibenzothiophene w as extracted from 1 000 mg/L n-hexane *** extraction efficiency obtained in this w ork w as higher than the previous reported *** desulfurization reaction w as kinetically follow ed the second order *** ionic liquid w as reusable and after four regeneration cycles 97%of its original extraction efficiency w as retained.

关键词：抽取 desulfurization 离子的液体 dibenzothiophene

Unconditionally Secure Oblivious Polynomial Evaluation:A Survey and New Results

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Journal of Computer Science & Technology 2022年第2期37卷 443-458页

作者： Louis Cianciullo hossein Ghodosi College of Science and Engineering James Cook UniversityTownsvilleQLD 4811Australia

Oblivious polynomial evaluation(OPE)is a two-party protocol that allows a receiver,R to learn an evaluation f(α),of a sender,S's polynomial(f(x)),whilst keeping both a and f(x)*** protocol has attracted a lot of attention recently,as it has wide ranging applications in the field of *** this article we review some of these applications and,additionally,take an in-depth look at the special case of information theoretic ***,we provide a current and critical review of the existing information theoretic OPE protocols in the *** divide these protocols into two distinct cases(three-party and distributed OPE)allowing for the easy distinction and classification of future information theoretic OPE *** addition to this work,we also develop several modifications and extensions to existing schemes,resulting in increased security,flexibility and ***,we also identify a security flaw in a previously published OPE scheme.

关键词： oblivious polynomial evaluation unconditionally secure information theoretic

POLYROTAXANE WITH π-CONJUGATED PORPHYRIN AND POLYAZOMETHINE SYSTEMS PREPARED FROM A TYPE OF PORPHYRIN-DIALDEHYDE AND COMPLEX OF β-CYCLODEXTRIN WITH 1,4-PHENYLENEDIAMINE

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Chinese Journal of Polymer Science 2013年第1期31卷 139-147页

作者： Raziyeh Akbarzadeh hossein Dehghani Department of Inorganic Chemistry Faculty of ChemistryUniversity of Kashan

The synthesis of 5,15-bis[4-（methoxycarbonyl）phenyl]-10,20-diphenylporphyrin （2） and its reduction to 5,15- bis[4-（hydroxymethyl）phenyl]-10,20-diphenylporphyrin （3）, and so its oxidation to provide 5,15-bis（4-formylphenyl）-10,20- diphenylporphyrin （4） are reported. The copolymer possessing β-cyclodextrin （fl-CD）, n-conjugated porphyrin and polyazomethine systems was synthesized by the polycondensation of porphyrin-dialdehyde monomer （4） and ,β- cyclodextrin/1,4-phenylenediamine complex （5）. The monomers and the copolymer were characterized by UV-Vis, ^1H-NMR and IR spectra. Furthermore, ^1H-NMR and FT-IR spectra confirmed locating the aromatic ring of 1,4-phenylenediamine molecule in the center of β-cyclodextrin cavity.

关键词： Polymer Porphyrin 1,4-Phenylenediamine Imine Cyclodextrin.

Molecular dynamics investigation of mechanical properties of single-layer phagraphene

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 495-503页

作者： Ali hossein Nezhad SHIRAZI Institute of Structural Mechanics Bauhaus-Universitat WeimarWeimarGermany

Phagraphene is a very attractive two-dimensional (2D) full carbon allotrope with very interesting mechanical, electronic, optical, and thermal properties. The objective of this study is to investigate the mechanical properties of this new graphene like 2D material. In this work, mechanical properties of phagraphene have been studied not only in the defect-free form, but also with the critical defect of line cracks, using the classical molecular dynamics simulations. Our study shows that the pristine phagraphene in zigzag direction experience a ductile behavior under uniaxial tensile loading and the nanosheet in this direction are less sensitive to temperature changes as compared to the armchair direction. We studied different crack lengths to explore the in fluence of defects on the mechanical properties of phagraphene. We also investigated the temperature effect on the mechanical properties of pristine and defective phagraphene. Our classical atomistic simulation results confirm that larger cracks can reduce the strength of the phagraphene. Moreover, it was shown the temperature has a considerable weakening effect on the tensile strength of phagraphene. The results of this study may be useful for the design of nano-devices using the phagraphene.

关键词： phaqraphene mechanical properties crack propagation molecular dynamics thermal effects

Developing an engineering-statistical model for estimating aerodynamic coefficients of helicopter fuselage

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Chinese Journal of Aeronautics 2017年第1期30卷 175-185页

作者： hossein Sheikhi Abas Saghaie Department of Industrial Engineering Science and Research Branch Islamic Azad University

The design of the geometric shape of a helicopter fuselage poses a serious challenge for designers. The most important parameter in determining the shape of the helicopter fuselage is its aerodynamic coefficients. These coefficients are determined using two methods： wind tunnel test and computational fluid dynamics（CFD） simulation. The first method is expensive, time-consuming and limited. In addition, estimates in regions away from data can be poor. The second method,due to the limitations of numerical solution, the number of nodes and the used solution, is often inaccurate. In this paper, with the aim of accelerating the design process and achieving results with reasonable engineering accuracy, an engineering-statistical model which is useful for estimating the aerodynamic coefficients was developed, which mitigated the drawbacks of these two ***, by combining CFD simulation and regression techniques, an engineering model was presented for the estimation of aerodynamic coefficients. Then, by using the data from a wind tunnel test and implementation of statistical adjustment, the engineering model was modified and an engineering-statistical model was obtained. By spending less time and cost, the final model provided the aerodynamic coefficients of a helicopter fuselage at the desired angles of attack with reasonable accuracy. Finally, three numerical examples were provided to illustrate the application of the proposed model. Comparative results demonstrate the effectiveness of the engineering-statistical model in estimating the aerodynamic coefficients of a helicopter fuselage.

关键词： Aerodynamic coefficients Computaticnal fluid dynamics (CFD) Engineering-statistical model Helicopter fuselage Wind tunnel test

HBIR: Hypercube-Based Image Retrieval

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Journal of Computer Science & Technology 2012年第1期27卷 147-162页

作者： hossein Ajorloo Abolfazl Lakdashti Department of Computer Engineering Sharif University of Technology Tehran Iran University College of Rouzbahan Sari Iran

In this paper, we propose a mapping from low level feature space to the semantic space drawn by the users through relevance feedback to enhance the performance of current content based image retrieval （CBIR） systems. The proposed approach makes a rule base for its inference and configures it using the feedbacks gathered from users during the life cycle of the system. Each rule makes a hypercube （HC） in the feature space corresponding to a semantic concept in the semantic space. Both short and long term strategies are taken to improve the accuracy of the system in response to each feedback of the user and gradually bridge the semantic gap. A scoring paradigm is designed to determine the effective rules and suppress the inefficient ones. For improving the response time, an HC merging approach and, for reducing the conflicts, an HC splitting method is designed. Our experiments on a set of 11 000 images from the Corel database show that the proposed approach can better describe the semantic content of images for image retrieval with respect to some existing approaches reported recently in the literature. Moreover, our approach can be better trained and is not saturated in long time, i.e., any feedback improves the precision and recall of the system. Another strength of our method is its ability to address the dynamic nature of the image database such that it can follow the changes occurred instantaneously and permanently by adding and dropping images.

关键词： image retrieval relevance feedback rule base hypercube (HC)

SYNTHESIS AND APPLICATIONS OF CROSS-LINKED POLY(DIALLYLDIMETHYL AMMONIUM CHLORIDE) AND ITS DERIVATIVE COPOLYMERS AS EFFICIENT PHASE TRANSFER CATALYST FOR NUCLEOPHILIC SUBSTITUTION REACTIONS

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Chinese Journal of Polymer Science 2011年第2期29卷 165-172页

作者： hossein Mahdavi Mahdi Mahmoudian School of Chemistry University College of ScienceUniversity of TehranTehranIran

Cross-linked poly（diallyldimethylammonium chloride） and its derivative copolymers were synthesized and used as phase transfer catalyst in the nucleophilic substitution reaction especially halogen exchange *** additi... 详细信息

关键词： Poly(diallyldimethylammonium chloride) Phase transfer catalyst Nucleophilic substitution reaction Halogen exchange reaction

Dynamic characteristics of bubbling fluidization through recurrence rate analysis of pressure fluctuations

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Particuology 2013年第3期11卷 282-287页

作者： hossein Sedighikamal Reza Zarghami Multiphase Systems Department Oil and Gas Processing Centre of ExcellenceSchool of Chemical EngineeringCollege of EngineeringUniversity of Tehran

Pressure fluctuations signals of a lab-scale fiuidized bed （15 cm inner diameter and 2 m height） at different superficial gas velocities were measured. Recurrence plot （RP） and recurrence rate （RR）, and the simplest variable of recurrence quantification analysis （RQA） were used to analyze the pressure signals. Different patterns observed in RP reflect different dynamic behavior of the system under study. It was also found that the variance of RR （a2R） Could reveal the peak dominant frequencies （PDF） of different dynamic systems： completely periodic, completely stochastic, Lorenz system, and fluidized bed. The results were compared with power spectral density. Additionally, the diagram of σ^2RR provides a new technique for prediction of transition velocity from bubbling to turbulent fluidization regime.

关键词： Pressure fluctuations Fluidization Recurrence rate Peak dominant frequency Transition velocity Power spectral density

An efficient design tool based on FEM for evaluating effects of components properties and operating conditions on interaction of tire with rigid road

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Journal of Central South University 2015年第1期22卷 189-195页

作者： Moslem Namjoo hossein Golbakhshi Department of Agricultural Machinery Engineering Faculty of AgricultureUniversity of Jiroft

It is noted that any variation in operating conditions has a considerable effect on the tire/road interaction. Furthermore,choosing a range of proper values for carcass stiffness is very essential for both tire safety and effective driving action. In this work,an elaborated 3D model fully compliant with the geometrical size of radial tire 185/60 R15 is worked up, for evaluating the effects of components properties and working conditions on deformation and stress/strain fields created inside the tire. For the simulation, the tire structure is assumed to be composed of tread, carcass ply, and bead. The mechanical behavior of rubber as main component of tire is described by Mooney-Rivlin material model. The comparison of the obtained results and laboratory tests demonstrates the validity and high accuracy of analysis.

关键词： rubber simulation carcass ply stiffness Mooney-Rivlin model

Experimental Evaluation of A New Developed Algorithm for An Autonomous Surface Vehicle and Comparison with Simulink Results

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China Ocean Engineering 2019年第3期33卷 268-278页

作者： hossein MOUSAZADEH Ali KIAPEY Mechanical Engineering of Biosystems University of Tehran Tehran Iran Mechanical Engineering of Biosystems and Expert of Ports and Maritime Organization Tehran Iran

Performing repeatable duties automatically was the dreams of human being for centuries. Although full autonomy has long been dreamed of by visionaries, many researches have been performed for surface vehicles automation since the last century to get close to this dream stepwise. To increase daily working hours and accuracy and reduce cost, operations such as hydrography are susceptible for autonomy. Beside platform topology, installed sensors and energy resources, the core elements of any autonomous surface vehicle are navigation, guidance and control systems. To perform bathymetry operation in autonomy manner, a reliable and robust navigation algorithm is designed and embedded in an autonomous surface vehicle titled Morvarid. Morvarid is a plug-in hybrid solar powered catamaran boat. The developed algorithm is a combination of extended Kalman filter, search ball and potential field approaches. Many experimental field tests are carried out after simulation in Simulink environment. Test results illustrated the algorithm and improved the path followed by reducing SD and RMSE and there is a good correlation between simulation run and experimental tests.

关键词： autonomous surface vehicle extended Kalman filter search ball trajectory tracking bathymetry