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An environmental friendly approach for the catalyst-free synthesis of highly substituted pyrazoles promoted by ultrasonic radiation

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Chinese Chemical Letters 2015年第11期26卷 1397-1399页

作者： Firouzeh Nemati seyed Hasan Nikkhah ali Elhampour Department of Chemistry Semnan University

A cost-effective, highly useful and eco-friendly procedure for the one-pot synthesis of highly substituted pyrazole derivatives has been developed via the reaction of various aldehydes, malononitrile and phenylhydrazine or 4-phenylthiosemicarbazide in PEG-400 and water at room temperature under ultrasound irradiation. Utilization of green solvents without a catalyst makes this methodology very interesting from economic and environmental perspectives. This method provides several advantages such as operational simplicity, use of accessible and economical starting materials and reduced environmental consequences.

关键词： Green chemistryMulticomponent reactionPyrazole Ultrasonic

Presentation of massive orbital hidrocystoma at birth:case report and review of the literature

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Eye and Vision 2017年第1期4卷 22-25页

作者： Bahram Eshraghi Mohammad-ali Abtahi seyed ali Sonbolastan Zahra Kasaie seyed-Hossein Abtahi Ophthalmology Department School of MedicineTehran University of Medical SciencesTehranIran Ophthalmology Department School of MedicineIsfahan University of Medical SciencesIsfahanIran Isfahan Eye Research Center Isfahan University of Medical SciencesFeiz HospitalQods Sq.IsfahanIran Pathology Department School of MedicineIsfahan University of Medical SciencesIsfahanIran

Background:Hidrocystoma,or sudoriferous cyst,is an eyelid tumor originating from apocrine or eccrine sweat *** presence in the orbit is relatively *** presentation:A full-term female child with severe right eye extrusion was referred to our department two hours after *** performed cyst aspiration under ultrasonic guidance;15 cc straw-colored fluid was obtained and proptosis resolved *** magnetic resonance imaging(MRI)showed a large unilocular retrobulbar mass with hypo-intensity in T1 and hyper-intensity in *** case underwent further daily ocular assessment until day 5;when proptosis began to worsen *** day 6,under general anesthesia,we performed aspiration and then the cyst was completely removed with an intact wall through a trans-conjunctival *** diameter of the aspirated cyst was about 4 *** pathologic consultation,a cystic cavity lined by a layer of sweat duct like epithelium with apical snouts consistent with the diagnosis of apocrine hidrocystoma was ***:To date,in the literature,six other cases of orbital hidrocystoma have been reported in childhood with protean clinical pictures;none of which presented at ***,we introduce the first case report at birth and also provide a review on the *** report strongly argues against the well reputed theory of traumatic origin for orbital hidrocystoma;it has been postulated that this tumor may be the result of sweat gland cells implantation through the *** thereby suggest the possible presence of choristomatous ectopic sweat gland cells in the orbit during embryogenesis.

关键词： Orbital hidrocystoma Pediatric orbital tumor Sudoriferous cyst

Extraction of seed oil from Diospyros lotus optimized using response surface methodology

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Journal of Forestry Research 2019年第2期30卷 709-719页

作者： Gholamhossein Sodeifian Nedasadat Saadati Ardestani seyed ali Sajadian Department of Chemical Engineering Faculty of Engineering University of Kashan Laboratory of Supercritical Fluids and Nanotechnology University of Kashan

Oil from seeds of Diospyros lotus was extracted using a conventional method with two different solvents:hexane and petroleum ether. A central composite design with response surface methodology were used to optimize the process. A second-order polynomial equation was employed, and ANOVA was applied to evaluate the impact of various operating parameters including extraction temperature(x_1; 44.9–70.1 °C), extraction time(x_2;5.0–10.0 h) and solvent to solid ratio(x_3;11.6–28.4 mL g^(-1)), on oil yield. Experiments to validate the model showed decent conformity between predicted and actual values. Extraction conditions for optimal oil yield were 61 °C, 8.75 h extraction duration and 19.25 mL g^(-1) solvent to solid ratio. Under these conditions, the oil yield was predicted to be 5.1340%. Oil samples obtained were then analyzed using gas chromatography. The fatty acid composition revealed the major fatty acids to be oleic acid(C18:1) and linoleic acid(C18:2). The analysis of oil also demonstrated a decent ratio between omega-3 and omega-6 fatty acids. The structure of seeds was imaged using scanning electron microscopy. Oil quality was analyzed thermogravimetrically and by Fourier transform infrared spectroscopy. The assigned nutritional features of the D. lotus oil suggested that it can be used as an edible oil in pharmaceutical and food industry in the future.

关键词： Diospyros lotus Solvent extraction Physicochemical properties Fatty acids Response surface methodology

Kinetic studies of the oxidative coupling of methane over the Mn/Na_2WO_4/SiO_2 catalyst

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Journal of Natural Gas Chemistry 2009年第1期18卷 25-34页

作者： seyed Mehdi Kamali Shahri seyed Mehdi Alavi Reaction Engineering Lab. Chemical Engineering Department Iran University of Science and Technology Tehran-Iran

Oxidative coupling of methane is a direct way to obtain C2 hydrocarbon, and Mn-Na-W/SiO2 catalyst is the most promising among all the catalysts. The 2%Mn/5%Na2WO4/SiO2 catalyst was prepared by the incipient wetness impregnation method. A 7-step heterogeneous reaction model of the oxidative coupling of methane to C2 hydrocarbons was conducted by co-feeding methane and oxygen at a total pressure of 1 bar over the catalyst. The kinetic measurements were carried out in a micro-catalytic fixed bed reactor. The kinetic data were obtained at the appropriate range of reaction conditions （4 kPa〈Po2 〈20 kPa, 20 kPa〈PcH4〈80 kPa, 800 ℃〈T〈900℃）. The proposed reaction kinetic scheme consists of three primary and four consecutive reaction steps. The conversions of hydrocarbons and carbon oxides were evaluated by applying Langmuir-Hinshelwood type rate equations. Power-law rate equation was applied only for the water-gas shift reaction. In addition, the effects of operating conditions on the reaction rate were studied. The proposed kinetic model can predict the conversion of methane and oxygen as well as the yield of C2 hydrocarbons and carbon oxides with an average accuracy of ± 15%.

关键词： kinetic model oxidative coupling of methane reaction rate

Two-phase SPH modelling of waves caused by dam break over a movable bed

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International Journal of Sediment Research 2014年第3期29卷 344-356页

作者： seyedeh Leila RAZAVITOOSI seyed ali AYYOUBZADEH alireza ValiZADEII Water Structures Engineering Department Tarbiat Modares UniversityJalal Ale Ahmad HighwayTehranIran Monash University Wellington RdClaytonVIC 3800Australia

This paper describes the application of the Smoothed Particle Hydrodynamics(SPH) method for modeling two dimensional waves caused by dam break over a movable bed in two *** two phase SPH method is developed to solve the Navier-Stokes *** fluid and sediment phases are described by particles as weakly compressible fluids and the incompressibility is achieved by the equation of *** sediment phase is modeled as a non-Newtonian fluid using three alternative approaches of artificial viscosity and Bingham *** this paper,the new formulations for two-phase flows are *** numerical results obtained from the developed SPH model show acceptable accuracy with comparison to experimental data.

关键词： Dam break Sediment Smoothed Particle Hydrodynamics(SPH)

Isogeometric analysis of free-form Timoshenko curved beams including the nonlinear effects of large deformations

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Acta Mechanica Sinica 2018年第4期34卷 728-743页

作者： seyed Farhad Hosseini ali Hashemian Behnam Moetakef-Imani Saied Hadidimoud Sun-Air Research Institute Ferdowsi University of Mashhad Department of Mechanical Engineering Hakim Sabzevari University Department of Mechanical Engineering Ferdowsi University of Mashhad Centre for Manufacturing and Materials Engineering Coventry University

In the present paper, the isogeometric analysis（IGA） of free-form planar curved beams is formulated based on the nonlinear Timoshenko beam theory to investigate the large deformation of beams with variable curvature. Based on the isoparametric concept, the shape functions of the field variables（displacement and rotation） in a finite element analysis are considered to be the same as the non-uniform rational basis spline（NURBS） basis functions defining the geometry. The validity of the presented formulation is tested in five case studies covering a wide range of engineering curved structures including from straight and constant curvature to variable curvature beams. The nonlinear deformation results obtained by the presented method are compared to well-established benchmark examples and also compared to the results of linear and nonlinear finite element analyses. As the nonlinear load-deflection behavior of Timoshenko beams is the main topic of this article, the results strongly show the applicability of the IGA method to the large deformation analysis of free-form curved beams. Finally, it is interesting to notice that, until very recently, the large deformations analysis of free-form Timoshenko curved beams has not been considered in IGA by researchers.

关键词： Curved beams Nonlinear Timoshenko beam theory Large deformation Isogeometric analysis NURBS curves

Microstructural analyses of aluminum–magnesium–silicon alloys welded by pulsed Nd: YAG laser welding

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 660-668页

作者： Hossain Ebrahimzadeh Hassan Farhangi seyed ali Asghar Akbari Mousavi Arman Ghahramani School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

Revealing grains and very fine dendrites in a solidified weld metal of aluminum–magnesium–silicon alloys is difficult and thus,there is no evidence to validate the micro-and meso-scale physical models for hot cracks. In this research, the effect of preheating on the microstructure and hot crack creation in the pulsed laser welding of AA 6061 was investigated by an optical microscope and field emission electron microscopy. Etching was carried out in the gas phase using fresh Keller’s reagent for 600 s. The results showed that the grain size of the weld metal was proportional to the grain size of the base metal and was independent of the preheating temperature. Hot cracks passed the grain boundaries of the weld and the base metal. Lower solidification rates in the preheated samples led to coarser arm spacing;therefore, a lower cooling rate. Despite the results predicted by the micro and meso-scale models, lower cooling rates resulted in increased hot cracks. The cracks could grow in the weld metal after solidification;therefore, hot cracks were larger than predicted by the hot crack prediction models.

关键词： etching technique laser welding inter-dendritic spacing grain size aluminum–magnesium–silicon alloys hot crack formation model

Techno-economic feasibility assessment of a diesel exhaust heat recovery system to preheat mine intake air in remote cold climate regions

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International Journal of Mining Science and Technology 2020年第4期30卷 517-523页

作者： Marco Antonio Rodrigues de Brito Durjoy Baidya seyed ali Ghoreishi-Madiseh Norman B.Keevil Institute of Mining Engineering The University of British ColumbiaVancouverBC V6T 1Z4Canada

Underground mines in Arctic and Subarctic regions require the preheating of mine intake air during *** cold fresh air of those remote areas can be as severe as40℃ and commonly needs to be heated to around+3℃.This extensive amount of heating is usually provided by employing large-size air heaters,fueled by diesel,propane,natural gas,or heavy oil,leading to high energy costs and large carbon *** the same time,the thermal energy content of a diesel generator sets(gen-sets)exhaust is known to be one-third of the total heating value of its combusted *** heat recovery from diesel gen-sets is a growing technology that seeks to mitigate the energy costs by capturing and redirecting this commonly rejected exhaust heat to other applications such as space heating or pre-heating of the mine intake *** present study investigated the possibility of employing a simple system based on off-theshelf heat exchanger technology,which can recover the waste heat from the exhaust of the power generation units(diesel gen-sets)in an off-grid,cold,remote mine in Canada for heating of the mine intake *** from a real mine was used for the analysis along with environmental data of three different location-scenarios with distinct *** developing a thermodynamic model,the heat savings were calculated,and an economic feasibility evaluation was *** proposed system was found highly viable with annual savings of up to C$6.7 million and capable enough to provide an average of around 75%of the heating demand for mine intake air,leading to a payback period of about eleven months or less for all *** of seasonal thermal energy storage has also been recommended to mitigate the mismatch between supply and demand,mainly in summertime,possibly allowing the system to eliminate fuel costs for intake air heating.

关键词： Exhaust heat recovery Mine energy management Mine heating Alternative energy Intake air heating

Nondestructive methods for determining the firmness of apple fruit flesh

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Information Processing in Agriculture 2021年第4期8卷 515-527页

作者： Zahed Fathizadeh Mohammad Aboonajmi seyed reza Hassan-Beygi Department of Agrotechnology College of AbouraihanUniversity of TehranTehranIran

Nowadays,many researches have been accomplished on the attributed quality assessment of agricultural *** have significantly contributed to these researches because of their high production and consumption,*** this paper,the nondestructive instrumental researches in the field of firmness assessment for apple fruit *** researches are important for all production and distribution chain activists such as farmers,insurance companies,packaging and transportation companies,wholesalers and *** studies can be used for examining texture quality,predicting the right time to harvest fruits and classifying them according to the level of ripeness and detecting the apparent and internal defects of the *** apple flesh firmness measurement methods consist of acoustic and mechanical vibration methods,optical methods such as hyperspectral scattering imaging,near infrared,ultrasound and other *** destructive puncture test method commonly used as a reference *** methods are accurate and quick that is suitable for online ***,the use of artificial intelligence methods and data fusion techniques to increase the accuracy of quality measuring of the products has been considered that in the future we will see further development of these methods in measuring the firmness of the apples.

关键词： Apple Firmness Internal quality Nondestructive