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Davarpanah J.,Production Technology Research Institute ACECR | Davarpanah J.,Shahid Chamran University | Kiasat A.R.,Shahid Chamran University
RSC Advances | Year: 2015

In the present work, amorphous silica nanoparticles were synthesized from low-cost rice husk ash (RH-SiO2). The nanoparticles were later modified by an acidic ionic liquid containing double-charged diazoniabi-cyclo[2.2.2]octane chloride using sol-gel method (RH@[SiPrDABCO@BuSO3H]HSO4). The structural properties of this Brönsted solid acid were systematically investigated by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermal gravimetric analysis-derivative thermogravimetric analysis (TGA-DTG), and Brunauer-Emmett-Teller (BET) measurements. The catalytic activity of this nanocomposite was successfully tested through the one-pot synthesis of 1H-pyrazolo[1,2-b]phthalazine-5,10-diones via three-component couplings of phthalhydrazide, aromatic aldehydes, and malononitrile. The heterogeneous catalyst could be recovered easily and reused without significant loss of its catalytic activity. © The Royal Society of Chemistry 2015. Source

Kiasat A.R.,Shahid Chamran University | Davarpanah J.,Production Technology Research Institute ACECR
Catalysis Communications | Year: 2015

Regarding the green chemistry's goals, the development of mesoporous silica materials as attractive candidates in the search for supporting of catalysts is currently a subject of increasing interest. Therefore, in the present research n-propyl-4-aza-1-azoniabicyclo[2.2.2]octane chloride-SBA-15 (SBA-DABCO) was used as a basic catalyst for the synthesis of 1,4-dihydropyridine (DHP) derivatives from one pot, three-component condensation of aromatic aldehydes, ammonium acetate and ethylacetoacetate under solvent-free at 80 °C. This method offers several advantages, including high yield, short reaction time, simple work-up procedure, ease of separation and recyclability of the catalyst, as well as the ability to tolerate a wide variety of substitutions in the reagents. © 2015 Elsevier B.V. All rights reserved. Source

Majd H.M.,Production Technology Research Institute ACECR | Azizpour M.J.,Production Technology Research Institute ACECR
International Conference on Manufacturing Engineering, Quality and Production Systems, MEQAPS - Proceedings | Year: 2011

In this paper back-propagation artificial neural network (BPANN) is employed to predict the limiting drawing ratio (LDR) of the deep drawing process. To prepare a training set for BPANN, some finite element simulations were carried out. die and punch radius, die arc radius, friction coefficient, thickness, yield strength of sheet and strain hardening exponent were used as the input data and the LDR as the specified output used in the training of neural network. As a result of the specified parameters, the program will be able to estimate the LDR for any new given condition. Comparing FEM and BPANN results, an acceptable correlation was found. Source

Mohammadi Majd H.,Production Technology Research Institute ACECR | Jalali Azizpour M.,Production Technology Research Institute ACECR
World Academy of Science, Engineering and Technology | Year: 2011

In this paper back-propagation artificial neural network (BPANN)with Levenberg-Marquardt algorithm is employed to predict the deformation of the upsetting process. To prepare a training set for BPANN, some finite element simulations were carried out. The input data for the artificial neural network are a set of parameters generated randomly (aspect ratio d/h, material properties, temperature and coefficient of friction). The output data are the coefficient of polynomial that fitted on barreling curves. Neural network was trained using barreling curves generated by finite element simulations of the upsetting and the corresponding material parameters. This technique was tested for three different specimens and can be successfully employed to predict the deformation of the upsetting process. Source

Davarpanah J.,Production Technology Research Institute ACECR | Rezaee P.,Islamic Azad University at Abadan | Elahi S.,Islamic Azad University at Abadan
Research on Chemical Intermediates | Year: 2015

A simple and convenient method has been used to prepare an [SBAIm] HSO4 composite on SBA-15 mesoporous silica as support. The surface of the mesoporous silica was modified by reaction with the ionic liquid 1-(triethoxysilylpropyl)- 3-methylimidazolium hydrogen sulfate (IL-HSO4). The resulting solid acid was characterized by infrared spectroscopy (FTIR), transmission and scanning electron microscopy, and thermogravimetric analysis. The acidic organocatalyst enables environmentally benign one-pot synthesis of phthalazinedione and phthalazinetrione heterocyclic compounds in ethanol. © Springer Science+Business Media Dordrecht 2015. Source

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