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First example of multicomponent synthesis of 1-ethoxy-3-(4-aryl)-1-phenyl- 1H-benzo[f]-chromene derivatives

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Chinese Chemical Letters 2012年第3期23卷 253-256页

作者： Saman Damavandi reza Sandaroos Majid Vafaeei hamid reza Molaei Department of Chemistry Sarvestan BranchIslamic Azad UniversitySarvestanIran Department of Chemistry Faculty of ScienceBirjand UniversityBirjandIran Department of Chemistry Mashhad BranchIslamic Azad UniversityMashhadIran

A new series of 1-ethoxy-3-（4-aryl）-1-phenyl-1H-benzo[f]chromenes have been synthesized *** procedure involves the multicomponent reaction of 2-naphthol,acetophenone derivatives,and triethyl orthobenzoate catalyzing... 详细信息

关键词： Multicomponent reaction Benzo[f]chromen Catalyst

Kaoline-based catalyst for a high stability desulfurization of sour heavy naphtha in a three-phase oscillatory baffled reactor

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Particuology 2024年第1期84卷 249-260页

作者： Hassan M.Hmood Saba A.Gheni Safaa M.R.Ahmed Mudheher M.Ali hamid Yonis Saleh Mohammed H.Mohammed Awad E.Mohammed Marwan A.Mahomood Hiba R.Mohammed Ahmed A.Hassan Adam Harvey North Refineries Company Ministry of OilIraq Chemical Engineering Department Tikrit UniversityIraq Ministry of Oil Iraq AL-Hawija Technical Institute Northern Technical UniversityMoselIraq School of Engineering Newcastle UniversityUK

To meet the rapidly increasing demand for energy and the dramatic depletion of conventional crude oil,it is imperative to utilize sour *** no coke being produced,oxidative desulfurization(ODS)of naphtha lowers its sulfur content and average molecular *** this article,we outline a method for heavy naphtha non-extractive ODS using a very stable *** technique involves the use of a solid catalyst with oxygen gas as the *** necessitated relatively high mixing intensities;hence a three-phase Oscillatory Baffled Reactor(OBR)was *** catalyst was based on the zeolite ZSM-5,prepared from natural kaolin by a series of delamination and activation steps and impregnated with Fe.A TiO2 nanolayer was applied,using the sol-gel method,to prevent rapid *** reactor performance was evaluated to minimize the sulfur content in the naphtha *** to the protective coating,the sulfur conversion stabilized at 90%.The results of this work establish the use of natural clay-based catalysts in a continuous,three-phase ODS,particularly with regard to proving long-term *** also showed that modest ODS can be achieved using an environmentally friendly oxidant,at mild operating conditions,whilst maintaining stability.

关键词： Natural kaoline Desulfurization Three-phase Oscillatory baffled reactor

Stabilization of a class of nonlinear discrete time systems with time varying delay

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Journal of Central South University 2014年第10期21卷 3769-3776页

作者： Maryam Fattahi Nastaran Vasegh hamid reza Momeni Faculty of Electrical and Computer Engineering Tarbiat Modares University Faculty of Electrical and Computer Engineering Shahid Rajaee Teacher Tehran Iran

The stability and stabilization of a class of nonlinear discrete time delayed systems(NDTDS) with time-varying delay and norm-bounded nonlinearity are investigated. Based on discrete time Lyapunov–Krasovskii functional method, a sufficient delaydependent condition for asymptotic stability of nonlinear systems is offered. Then, this condition is used to design a new efficient delayed state feedback controller(DSFC) for stabilization of such systems. These conditions are in the linear matrix inequality(LMI) framework. Illustrative examples confirm the improvement of the proposed approach over the similar cases. Furthermore, the obtained stability and stabilization conditions will be extended to uncertain discrete time delayed systems(UDTDS) with polytopic parameter uncertainties and also with norm-bounded parameter uncertainties.

关键词： nonlinear discrete time delayed systems Lyapunov–Krasovskii functional delayed state feedback linear matrix inequality(LMI) polytopic parameter uncertainties norm bounded parameter uncertainties

Responses of Four Rice Varieties to Elevated CO_2 and Different Salinity Levels

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Rice science 2018年第3期25卷 142-151页

作者： Sheidollah KAZEMI hamid reza ESHGHIZADEH Morteza ZAHEDI Department of Agronomy and Plant breeding College of Agriculture Isfahan University of Technology

This study was carried out in 2014 at Isfahan University of Technology, Iran, to evaluate the responses of four rice varieties(Neda, Deylamani, Shiroudi and Domsorkh) to ambient(360 ± 50 μmol/mol) and elevated(700 ± 50 μmol/mol) air carbon dioxide(CO_2) concentrations under four salinity levels(0, 30, 60 and 90 mmol/L Na Cl). There was significant variation among rice varieties in response to elevated CO_2 concentration under the four salinity levels. Under non-saline condition, elevated CO_2 increased the dry weight of Neda, Deylamani and Domsorkh by 8%, 50% and 8%, respectively, but reversely decreased that of Shiroudi by 34%. Increasing CO_2 concentration significantly reduced the negative effects of salinity on Shiroudi, but these effects were even increased in Deylamani and Domsorkh under all the salinity levels and in Neda only under 30 and 60 mmol/L Na Cl. Significant correlations were established between plant dry weight, SPAD value and leaf area under both CO_2 levels. However, this trend was observed only at ambient CO_2 concentration in the presence of soluble carbohydrates. The results revealed the genotype and salinity dependence of the effects of CO_2 concentrations on the rice traits investigated.

关键词： CO2 concentration genetic diversity salt tolerance water soluble carbohydrate

Efficient Multi-component Synthesis of Highly Substituted Imidazoles Utilizing P2O5/SiO2 as a Reusable Catalyst

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Chinese Journal of Chemistry 2011年第8期29卷 1635-1645页

作者： Shaterian, hamid reza Ranjbar, Mohammad Azizi, Kobra Department of Chemistry Faculty of Sciences University of Sistan and Baluchestan PO Box 98135-674 Zahedan Iran

Phosphorus pentoxide supported on silica gel （P2O5/SiO2） has been used as an efficient and reusable catalyst for the one-pot pseudo four-component synthesis of 2,4,5-trisubstituted imidazoles from benzil or benzoin, aldehydes, and ammonium acetate. It was also used for four-component preparation of 1,2,4,5-tetrasubstituted imidazoles from benzil or benzoin, aldehydes, primary amine, and ammonium acetate under thermal solvent-free conditions. The remarkable features of this new procedure are high conversions, cleaner reaction, simple experimental and work-up procedures and also the catalyst can be easily separated from the reaction mixture and reused several times without any loss of its activity.

关键词： multicomponent reactions domino reactions phosphorus pentoxide supported on silica gel,2,4,5-trisubstituted imidazoles 1,2,4,5-tetrasubstituted imidazoles heterogeneous catalysis

Effects of Functionalized Silica Nanoparticles on Characteristics of Nanocomposites PES Cation Exchange Membranes

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Journal of Wuhan University of Technology(Materials Science) 2017年第6期32卷 1239-1249页

作者： GARMSIRI Mahdi MORTAHEB hamid reza MOGHADASI Mahdieh Chemistry and Chemical Engineering Research Center of lran Tehran P.O.Box: 14335-186 Iran

Nanocomposite cation exchange membranes（CEMs） were prepared by adding various loadings of functionalized silica nanoparticles to the sulfonated polyethersulfone（s PES） polymeric matrix. The silica nanoparticles were functionalized by mercaptopropyl（F1, IEC=0）, propylsulfonic acid（F2, IEC= 2.71）, and sulfonic acid（F3, IEC=2.84）. The properties of prepared membranes were investigated by varying the loadings of functionalized silica nanoparticles. Applying functionalized nanoparticles provides additional ion exchange groups and enhances water contents as well as conductivities and permselectivities of the membranes. The maximum IEC of 1.9 meq.g^-1 was obtained for the membrane having 3 wt% F3 nanoparticles and the maximum conductivity of 0.237 S·cm^-1 was achieved for the membrane having 2 wt% F3 nanoparticles, which were 19.6% and 64% higher than the corresponding values for s PES membrane, respectively. The excellent properties of the nanocomposite cation-exchange membranes make them appropriate candidates for electrodialysis and desalination processes.

关键词： functionalized silica nanocomposite membrane cationic exchange membrane polyethersulfone transport properties

Effects of copper content on the shell characteristics of hollow steel spheres manufactured using an advanced powder metallurgy technique

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International Journal of Minerals,Metallurgy and Materials 2016年第4期23卷 434-441页

作者： hamid Sazegaran Ali-reza Kiani-Rashid Jalil Vahdati Khaki Department of Materials Science and Metallurgical Engineering Engineering Faculty Ferdowsi University of Mashhad

Metallic hollow spheres are used as base materials in the manufacture of hollow sphere structures and metallic foams. In this study, steel hollow spheres were successfully manufactured using an advanced powder metallurgy technique. The spheres＇ shells were characterized by optical microscopy in conjunction with microstructural image analysis software, scanning electron microscopy（SEM）, energy-dispersive X-ray spectroscopy（EDX）, and X-ray diffraction（XRD）. The microscopic evaluations revealed that the shells consist of sintered iron powder, sintered copper powder, sodium silicate, and porosity regions. In addition, the effects of copper content on various parameters such as shell defects, microcracks, thickness, and porosities were investigated. The results indicated that increasing the copper content results in decreases in the surface fraction of shell porosities and the number of microcracks and an increase in shell thickness.

关键词： steel hollow spheres powder metallurgy copper content shell characteristics

Multi-objective optimization of the kinematic parameters of fish-like swimming using a genetic algorithm method

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Journal of Hydrodynamics 2019年第2期31卷 333-344页

作者： Mahdi Abolfazli Esfahani hamid reza Karbasian Kyung Chun Kim Department of Electrical and Electronics Engineering Nanyang Technological UniversitySingapore School of Mechanical Engineering Pusan National UniversityBusan 46241Korea

This paper investigates the kinematic optimization of fish-like ***,an experiment was performed to detect the motion of the fish tail foil of a fish ***,the kinematic swimming model was verified experimentally using an image processing *** model includes two rotational motions:caudal foil motion and foil-pitching *** kinematic model allows us to evaluate the influence of motion trajectory in the optimization *** optimize the propulsive efficiency and thrust,a multi-objective genetic algorithm was employed to handle with kinematic,hydrodynamic,and propulsion *** results show that the caudal length has a significant effect on the performance of the flapping foil in fish-like swimming,and its influence on the motion trajectory may increase the propulsive efficiency to as high as 98%in ideal *** maximum thrust coefficient can also reach approximately 3 in ideal conditions.

关键词： Fish-like swimming fish robot hydrodynamics optimization genetic algorithm

Effects of sphere size on the microstructure and mechanical properties of ductile iron–steel hollow sphere syntactic foams

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International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 676-682页

作者： hamid Sazegaran Ali-reza Kiani-Rashid Jalil Vahdati Khaki Department of Metallurgical and Materials Engineering Faculty of Engineering Ferdowsi University of Mashhad

The effects of sphere size on the microstructural and mechanical properties of ductile iron–steel hollow sphere（DI–SHS） syntactic foams were investigated in this study. The SHSs were manufactured by fluidized-bed coating via the Fe-based commercial powder–binder suspension onto expanded polystyrene spheres（EPSs）. Afterwards, the DI–SHS syntactic foams were produced via a sand-mold casting process. The microstructures of specimens were investigated by optical microscopy, scanning electron microscopy（SEM）, and energy-dispersive X-ray spectroscopy（EDS）. The microscopic evaluations of specimens reveal distinct regions composed of the DI matrix, SHS shells, and compatible interface. As a result, the microstructures and graphite morphologies of the DI matrix depend on sphere size. When the sphere size decreases, the area fractions of cementite and graphite phases are observed to increase and decrease, respectively. Compression tests were subsequently conducted at ambient temperature on the DI–SHS syntactic foams. The results reveal that the compression behavior of the syntactic foams is enhanced with increasing sphere size. Furthermore, the compressed specimens demonstrate that microcracks start and grow from the interface region.

关键词： ductile iron steel syntactic foams microstructure mechanical properties