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Chinese Chemical Letters 2012年第12期23卷 1327-1330页

作者： iman mohammadzadeh Hassan Sheibani University of Applied Science and Technology of Kerman Department of Chemistry Shahid Bahonar University of Kerman

In this investigation a new strategy involves the one-pot, three-component reaction of malononitrile, salycilaldehyde and phenol derivatives in the presence of high surface area of MgO is extended to the formation of chromeno[3,4-c]ehromene derivatives in good to excellent yields in a short reaction time. Also, the three component reactions of an aldehyde such as salycilaldehyde and ketones with malononitril for the formation of chromeno[3,4-c]pyridines are investigated.

关键词： Salycilaldehyde Chromeno[3,4-c]chromenes 2-Amino-4-aryl pyddylcyanides malononitrile

Microstructure and Corrosion Resistance of Dissimilar Weld-Joints between Duplex Stainless Steel 2205 and Austenitic Stainless Steel 316L

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Journal of Materials Science & Technology 2016年第3期32卷 282-290页

作者： Aboulfazl Moteshakker iman Danaee Abadan Faculty of Petroleum Engineering Petroleum University of Technology

The microstructure and corrosion resistance of dissimilar weld-joints between stainless steel SAF 2205 and stainless steel AISI 316L were investigated. Welding was accomplished by different types of welding wires AWS ER 347, AWS ER 316L and AWS ER 309L. To verify soundness of welded samples, nondestructive tests were performed. Metallographic samples were prepared from cross-section areas of weld- joints to investigate microstructure of different regions of weld-joints by optical microscopy and scanning electron microscopy. Corrosion resistance of weld-joints was evaluated in NaCI solution by potentiodynamic polarization and electrochemical impedance techniques. In the weld metal AWS ER 347, the brittle sigma phase was created, resulting in the decrease of weld-joint corrosion resistance. According to the results of metallurgical investigations and corrosion tests, welding wire AWS ER 309L was suitable for welding duplex stainless steel （SAF 2205） to austenitic stainless steel （AIS1316L） by gas tungsten arc welding （GTAW） process.

关键词： Duplex stainless steel Joint welding Microstructure Polarization Impedance

Free Vibration Analysis of Functionally Graded Plates with Multiple Circular and Non-circular Cutouts

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 277-284页

作者： JANGHORBAN Maziar ROSTAMSOWLAT iman Department of Mechanical Engineering Shiraz BranchIslamic Azad UniversityShirazIran

Cutouts are inevitable in structures due to practical *** order to investigate the free vibration of functionally graded plates with multiple circular and non-circular cutouts,finite element method is *** volume fraction of the material constituents is assumed to follow a simple power law *** parameters considered in this paper are as follows：cutout size,cutout location,number of cutouts and different boundary *** should be mentioned that free vibration for FG plates（such as rectangular？skew？trapezoidal？circular plates） with multiple cutouts has not been studied yet and hence the results out coming from this paper may be used as bench marks for future works.

关键词： graded materials rectangular?skew?trapezoidal?circular plates multiple circular/non-circular cutouts

Effect of functionally-graded interphase on the elasto-plastic behavior of nylon-6/clay nanocomposites;a numerical study

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Defence Technology（防务技术） 2021年第1期17卷 177-184页

作者： Maziyar Bazmaraa Mohammad Silani iman Dayyani Department of Mechanical Engineering University of HoustonTX 77204United States Centre for Structures Assembly and Intelligent AutomationCranfield UniversityCranfieldBedford MK430ALUnited Kingdom Department of Mechanical Engineering Isfahan University of TechnologyIsfahan84156-83111Iran

In nanocomposites,the interphase thickness may be comparable to the size of nano-particles,and hence,the effect of interphase layers on the mechanical properties of nanocomposites may be *** interphase thickness to the nano-particle size ratio and properties variability across the interphase thickness are the most important affecting parameters on the overall behavior of *** this study,the effect of properties variability across the interphase thickness on the overall elastic and elastoplastic properties of a polymeric clay nanocomposite(PCN)using a functionally graded(FG)interphase is investigated in *** results of the computational homogenization on the mesoscopic level show that Young’s modulus variation of the interphase has a significant effect on the overall elastic response of nanocomposites in a higher clay weight ratio(Wt).Moreover,strength variation through the interphase has a notable effect on the elasto-plastic properties of ***,the increase or decrease in stiffness of interphase from clay to matrix and vice versa have a similar effect in the overall behavior of nanocomposites.

关键词： Nylon 6/clay nanocomposites FG Interphase Computational homogenization

Simulation of quantum-well slipping effect on optical bandwidth in transistor laser

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Chinese Optics Letters 2009年第5期7卷 435-436页

作者： Hassan Kaatuzian Seyed iman Taghavi Photonics Research Laboratory Electrical Engineering DepartmentAmirkabir University of Technology

An optical bandwidth analysis of a quantum-well （16 nm） transistor laser with 150-μm cavity length using a charge control model is reported in order to modify the quantum-well location through the base region. At constant bias current, the simulation shows significant enhancement in optical bandwidth due to moving the quantum well in the direction of collector-base junction. No remarkable resonance peak, limiting factor in laser diodes, is observed during this modification in transistor laser structure. The method can be utilized for transistor laser structure design.

关键词： well Simulation of quantum-well slipping effect on optical bandwidth in transistor laser

Experimental investigation of flow and distortion mitigation by mechanical vortex generators in a coupled serpentine inlet-turbofan engine system

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Chinese Journal of Aeronautics 2020年第5期33卷 1375-1391页

作者： iman MAGHSOUDI Mohammad Ali VAZIRY Mostafa MAHMOODI Department of Aerospace Malek-Ashtar University of TechnologyTehran 158751774Iran Department of Aerospace Malek-Ashtar University of TechnologyIsfahanShahinshahr 115/83145Iran

The performance of compact,aggressive ducts in advanced propulsion systems is limited by the internal flow separation coupled with the formation of secondary counter-rotating vortices that give rise to intensive flow distortions at the duct *** experimental investigation was conducted to study the flow field and passive suppression of flow separation and Aerodynamic Interface Plane (AIP) distortion in a serpentine air inlet *** were performed by a turbofan engine at several Engine Operating Points (EOPs) from 56%(idle) to 100%(max).A large total pressure deficit region arose at the upper part of the AIP,which was associated with the upper surface flow *** the new mechanical S-type vortex generators in two longitudinal positions (VGl and VG2),separation and loss were diminished at the upper part of the duct and *** VG2 arrangement attained the maximum reductions in distortion coefficients which were 73.72%,60.7% and 37.8% in DC(90°),DC(60°) and△P_C/P metrics,*** the next step of the study,some unsteady aspects of the flow field were analyzed inside the *** separation onset and reattachment points were determined by the standard deviation of static pressure on the upper *** AIP spectral distribution showed that the boundary of low pressure and high pressure recovery regions was dominated by the maximum ***,the PSD diagram of several probes at AIP revealed the vortex shedding frequency and its higher harmonics at separation *** energy content of distinct unsteady spectral features in the bare configuration was significantly reduced using VGs,which showed the improvement of flow at the duct exit.

关键词： Distortion coefficient Power spectral density Serpentine inlet Total pressure Vortex generators

Lead removal from aqueous medium using fruit peels and polyaniline composites in aqueous and non-aqueous solvents in the presence of polyethylene glycol

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Chinese Journal of Chemical Engineering 2022年第4期35卷 253-259页

作者： iman Farirzadeh Majid Riahi Samani Davood Toghraie Department of Civil Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran

In the present study,composites of Polyaniline and some fruit peels were synthesized in various conditions and used for lead removal from aqueous *** tests were conducted in batch mode using the most efficient adsorbent,and the effects of medium pH,initial lead concentration,contact time,adsorbent dosage,and adsorption isotherms were *** results showed that all composites were more efficient in lead removal compared to the fruit peels *** highest removal percentage was related to the composite of banana peel and Polyaniline that synthesized in the aqueous solution in the presence of 2 g·L^(-1) Poly ethylene *** composite showed 95.96%lead adsorption at pH=6,the contact time of 90 min,the initial lead concentration of 25 mg·L^(-1),and an adsorbent concentration of 8 g·L^(-1).Adsorption isotherm study showed that adsorption of lead by synthesized composite could be fitted by both Langmuir and Freundlich models,but the Langmuir model was more fitted than ***,some characteristics of the composites,such as chemical composition(XRD analysis),structure,and morphology(SEM analysis)and functional groups(FTIR analysis),were studied.

关键词： Adsorption Banana peel Composites Pollution Polyaniline

Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beam based on experimental and numerical analyses

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 675-689页

作者： iman FATTAHI Hamid Reza MIRDAMADI Hamid ABDOLLAHI Department of Mechanical Engineering Isfahan University of TechnologyIsfahan ***Iran

Analyzing static and dynamic problems including composite structures has been of high significance in research efforts and industrial *** this article,equivalent single layer approach is utilized for dynamic finite element procedures of 3D composite beam as the building block of numerous composite *** this model,both displacement and strain fields are decomposed into cross-sectional and longitudinal components,called consistent geometric decomposition ***,the model is discretized using finite clement *** local coordinate systems and a global one are defined to decouple mechanical degrees of ***,from the viewpoint of consistent geometric decomposition theorem,the transformation and element mass matrices for those systems are introduced here for the first *** same decomposition idea can be used for developing element stiffiness ***,comprehensive validations are conducted for the theory against experimental and numerical results in two case studies and for various conditions.

关键词： composite beam dynamic finite element degrees of freedom coupling experimental validation numerical validation

Development of the applicability of simplified Henry’s method for skewed multicell box-girder bridges under traffic loading conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第12期13卷 915-925页

作者： iman MOHSENI A.R.Khalim RASHID Department of Civil Engineering Universiti Kebangsaan Malaysia(National University of Malaysia)

Concrete precast multicell box-girder(MCB) bridges combine aesthetics with torsional stiffness *** analytical studies indicate that currently available specifications are unable to consider the effect of the twisting moment(torsional moment) on bridge *** straight bridges the effect of torsion is negligible and the transverse reinforced design is governed by other ***,in the case of skewed bridges the effect of the twisting moment should be ***,an in-depth study was performed on 90 concrete MCB bridges with skew angles ranging from 0° to 60°.For each girder the bridge actions were determined under the American Association of State Highway and Transportation Officials(AASHTO) live load *** analytical results show that torsional stiffness and live load positions greatly affected the bridges' *** addition,based on a statistical analysis of the obtained results,several skew correction factors are proposed to improve the precision of the simplified Henry's method,which is widely used by bridge engineers to predict bridge *** relationship between the bending moment and secondary moments was also investigated and it was concluded that all secondary actions increase with an increase in skewness.

关键词： Distribution factor Live loads Skewed bridges Grillage analysis

A potpourri of pancreatic issues

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World Journal of Gastroenterology 2007年第47期13卷 6327-6332页

作者： iman Zandieh Michael F Byrne Division of Gastroenterology Department of MedicineUniversity of British ColumbiaVancouverBritish ColumbiaCanada

Autoimmune pancreatitis has emerged over the last 40 years from a proposed concept to a well established and recognized entity. As an efficient mimicker of pancreatic carcinoma, its early and appropriate recognition are crucial. With mounting understanding of its pathogenesis and natural history, significant advances have been made in the diagnosis of autoimmune pancreatitis. The characteristic laboratory features and imaging seen in autoimmune pancreatitis are reviewed along with some of the proposed diagnostic criteria and treatment algorithms.

关键词： Autoimmune pancreatitis Chronic pancreatitis Idiopathic pancreatitis Sclerosing pancreatitis