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    Efficient synthesis of propargylamines in aqueous media catalyzed by au nanoparticles under ambient temperature

    , Article ChemistrySelect ; Volume 3, Issue 7 , 2018 , Pages 2053-2058 ; 23656549 (ISSN) Matloubi Moghaddam, F ; Pourkaveh, R ; Sharif University of Technology
    Wiley-Blackwell  2018
    Abstract
    An eco-friendly gold-based catalyst supported on proline decorated montmorillonite was synthesized. The catalyst was characterized by combination of Fourier-transform infrared spectroscopy (FT-IR), Field Emission Scanning Electron Microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer–Emmett Teller (BET) surface area analysis, Ultraviolet–visible spectroscopy (UV-Vis), Energy-dispersive X-ray spectroscopy (EDX), thermo gravimetric analysis (TGA) and atomic absorption spectroscopy (AAS) techniques. The synthesized catalyst was found to be a highly efficient heterogeneous nanocatalyst for multi component A3 coupling reaction of aldehyde, amine and alkyne... 

    Mechanical and thermal properties of montmorillonite-epoxy nanocomposite

    , Article International Journal of Modern Physics B ; Volume 22, Issue 18-19 , 2008 , Pages 3247-3253 ; 02179792 (ISSN) Marouf, B. T ; Bagheri, R ; Pearson, R. A ; Sharif University of Technology
    World Scientific Publishing Co. Pte Ltd  2008
    Abstract
    In this investigation, the mechanical and thermal properties of the montmorillonite-epoxy nanocomposites were studied. The epoxy compounds were prepared by in situ polymerization and the intercalation dispersion were obtained as evidenced using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results reveal remarkable stiffening effect and slight toughening effect of the MMT in the epoxy resin and an insight about the crack tip and notch tip toughening mechanism. According to the DMA, the glass transition temperature increases as increasing the MMT content. © 2008 World Scientific Publishing Company  

    Microwave-expedited synthesis of aromatic aldehydes and ketones from alkyl halides without solvent using wet montmorillonite K 10 supported iodic acid as oxidant

    , Article Acta Chimica Slovenica ; Volume 51, Issue 2 , 2004 , Pages 333-336 ; 13180207 (ISSN) Mahmoudi Hashemi, M ; Rahimi, A ; Ahmadibeni, Y ; Sharif University of Technology
    2004
    Abstract
    The efficient microwave-assisted synthesis of aldehydes and ketones over wet montmorillonite K 10 using HIO3 as oxidizing agent is described. This fast oxidation protocol is applicable to variety of alkyl halides  

    Efficient and practical solvent-free oxidation of alcohols using microwave irradiation

    , Article Journal of Chemical Research - Part S ; Issue 6 , 2002 , Pages 286-287 ; 03082342 (ISSN) Mojtahedi, M. M ; Sharifi, A ; Kaamyabi, S ; Saidi, M. R ; Sharif University of Technology
    Scientific Reviews Ltd  2002
    Abstract
    Alcohols are oxidised rapidly to the corresponding carbonyl compounds by montmorillonite KSF or silica supported barium manganate, under solvent-free conditions and microwave irradiation  

    Transition metal free oxidation of alcohols to carbonyl compounds using hydrogen peroxide catalyzed with LiCl on montmorillonite K10

    , Article Acta Chimica Slovenica ; Volume 54, Issue 3 , 2007 , Pages 635-637 ; 13180207 (ISSN) Eftekhari Sis, B ; Khalili, B ; Abdollahifar, A ; Hashemi, M. M ; Sharif University of Technology
    2007
    Abstract
    Alcohols have been successfully converted into their corresponding carbonyl compounds using hydrogen peroxide catalyzed by lithium chloride on montmorillonite K10. Clay supported lithium chloride can be recovered after using as catalyst for oxidation of alcohols. The future runs according to this procedure showed no considerable decrease in the reaction yield and catalyst effect  

    Oxidation of benzylic alcohols to carbonyl compounds with hydrogen peroxide catalysed by manganeses chloride supported on montmorillonite K10

    , Article Journal of Chemical Research ; Issue 8 , 2005 , Pages 484-485 ; 03082342 (ISSN) Hashemi, M. M ; Khalili, B ; Eftekhari-sis, B ; Sharif University of Technology
    Scientific Reviews Ltd  2005
    Abstract
    Manganeses(II) chloride supported on montmorillonite K10 was found to be an efficient catalysts for the oxidation of alcohols to carbonyl compounds with hydrogen peroxide as oxidant  

    A novel and simple solvent free method for nucleophilic aromatic substitution of inactive aryl halides

    , Article Synthetic Communications ; Volume 34, Issue 15 , 2004 , Pages 2783-2787 ; 00397911 (ISSN) Hashemi, M. M ; Akhbari, M ; Sharif University of Technology
    2004
    Abstract
    A simple, high yield, and short time method for nucleophilic displacement reaction of inactive aryl halides is reported. The reaction is performed in microwave oven under thermal condition with montmorillonite supported AgNO 3  

    Oxidation of alcohols and primary aliphatic amines to carbonyl compounds using sodium hypochlorite adsorbed on montmorillonite K10

    , Article Journal of Chemical Research - Part S ; Issue 5 , 2000 , Pages 224-225 ; 03082342 (ISSN) Hashemi, M. M ; Beni, Y. A ; Sharif University of Technology
    Scientific Reviews Ltd  2000
    Abstract
    NaClO adsorbed on montmorillonite K10 converts alcohols and primary aliphatic amines into corresponding carbonyl compounds  

    A green and efficient deoximation using H2O2 catalyzed by montmorillonite-K10 supported CoCl2

    , Article Chinese Chemical Letters ; Volume 18, Issue 12 , December , 2007 , Pages 1451-1454 ; 10018417 (ISSN) Ezabadi, A ; Najafi, G. R ; Hashemi, M. M ; Sharif University of Technology
    2007
    Abstract
    Oximes were oxidized to the corresponding carbonyl compounds in good to high yields by environmentally friendly and green oxidant, H2O2 catalyzed by montmorillonite K-10 supported cobalt(II) chloride. © 2007 Ali Ezabadi  

    A mild and efficient oxidation of benzylic alcohols without solvent using iodic acid supported on wet montmorillonite K10 or silica gel under microwave irradiation

    , Article Acta Chimica Slovenica ; Volume 52, Issue 1 , 2005 , Pages 86-87 ; 13180207 (ISSN) Hashemi, M. M ; Rahimi, A ; Karimi Jaberi, Z ; Ahmadibeni, Y ; Sharif University of Technology
    2005
    Abstract
    Iodic acid supported on wet silica gel and K10 clay are used for the efficient oxidation of benzylic alcohols under microwave irradiation and solvent free condition  

    A new one-pot, solvent free synthesis of diethyl 3,3-thiodipropenoate

    , Article Journal of Sulfur Chemistry ; Volume 25, Issue 2-3 , 2004 , Pages 95-99 ; 17415993 (ISSN) Hashemi, M. M ; Akhbari, M ; Arianfar, S ; Sharif University of Technology
    2004
    Abstract
    Three isomers of diethyl 3,3-thiodipropenoate (DETDP) have been prepared as new compounds by the solvent free reaction of ethyl propiolate and thioamides or sodium sulfide in a short time and high yields  

    Enzymatic and soil burial degradation of corn starch/glycerol/sodium montmorillonite nanocomposites

    , Article Polymers from Renewable Resources ; Volume 11, Issue 1-2 , 2020 , Pages 15-29 Ostadi, H ; Gilak Hakimabadi, S ; Nabavi, F ; Vossoughi, M ; Alemzadeh, I ; Sharif University of Technology
    SAGE Publications Ltd  2020
    Abstract
    In this study, effects of glycerol (10, 20, and 30 wt%) and Sodium Montmorillonite (Na-MMT) (0%, 2.5%, and 5%) contents on the degradation of corn starch polymers were investigated. Films were prepared by casting corn starch solution using a modified method to enhance the nanoclay distribution. Biodegradability studies were performed by enzymatic and burial tests using pristine and enriched soils. The biodegradability of samples in pristine soil was faster, and all samples were fully degraded in 6 months. The effect of nanoparticles on the mass reduction in degradation was more pronounced than that of glycerol. In all glycerol concentrations, Na-MMT addition increased tensile strength. FTIR... 

    Experimental Investigation of a Nnanofibrous Membrane Preparation for Dye Removal from Colored Wastewater

    , Ph.D. Dissertation Sharif University of Technology Hosseini, Abolhassan (Author) ; Vossoughi, Manouchehr (Supervisor) ; Mahmoodi, Niyaz Mohammad (Supervisor)
    Abstract
    In this research, an adsorptive affinity membrane has been prepared based on the combination of the nanofiber structure’s intrinsic characteristic in the dye adsorption and its membrane filtration properties. Electrospinning method has been used to prepare chitosan/poly(vinyl alcohol) (PVA) nanofibers. The morphology and properties of the prepared nanofibrous membranes were characterized using Fourier-transform infrared spectroscopy (FT-IR), field-emission scanning electron microscopy (FE-SEM), image processing, atomic force microscopy (AFM), and thermogravimetric analysis (TGA). Also, the major drawback of electrospun nanofibrous membranes (ENMs) is their low mechanical resistance. So,... 

    Designing Polymeric Biomaterials based on Polysaccharides with Tissue Adhesion and Hemostasis Performance

    , M.Sc. Thesis Sharif University of Technology Shokrani, Hanieh (Author) ; Mashayekhan, Shohreh (Supervisor) ; Kordzadeh, Azadeh (Co-Supervisor)
    Abstract
    Death can be the result of severe bleeding which is associated with the loss of a high amount of blood like what happens in accidents, wars, or operations. Classic methods to stop bleeding are mostly ineffective to decrease the hemostasis time and the volume of the lost blood. A wide variety of products like powders, foams, and hydrogels have been designed and synthesized either from natural or synthetic polymers. However, limitations like weak tissue adhesion, creating a moist environment in the wound site, infection, weak biodegradation, and hemolysis still have remained. Among the existing options to be used as hemostasis agents, polysaccharides can be appropriate considering their great... 

    ZrOCl2·8H2O on montmorillonite K10 accelerated conjugate addition of amines to α,β-unsaturated alkenes under solvent-free conditions

    , Article Tetrahedron ; Volume 62, Issue 4 , 2006 , Pages 672-677 ; 00404020 (ISSN) Hashemi, M. M ; Eftekhari-Sis, B ; Abdollahifar, A ; Khalili, B ; Sharif University of Technology
    2006
    Abstract
    At room temperature, ZrOCl2·8H2O on montmorillonite K10 efficiently catalyzes conjugate addition of amines to a variety of conjugated alkenes such as α,β-unsaturated carbonyl compounds, carboxylic esters, nitriles and amides under solvent-free conditions. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency. © 2005 Elsevier Ltd. All rights reserved  

    Clay-based electrospun nanofibrous membranes for colored wastewater treatment

    , Article Applied Clay Science ; Volume 168 , 2019 , Pages 77-86 ; 01691317 (ISSN) Hosseini, S. A ; Vossoughi, M ; Mahmoodi, N. M ; Sadrzadeh, M ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Novel montmorillonite (Mt) chitosan/poly(vinyl alcohol) (PVA) nanocomposite electrospun nanofibrous membranes (ENM) were prepared and utilized for the treatment of colored wastewater. The Mt. with different mass percentages (0, 1.0, 2.0 and 3.0 mass%) was added to the membrane structure, and its effect on morphology, pore size, porosity, mechanical strength, and permeation properties of ENM were investigated. The fabricated membranes were used as affinity membranes for dye removal with ultrafast permeating adsorption. The results showed that incorporating Mt. as a reinforcing agent improved the nanocomposite ENM resistance to compaction. Young's modulus for the prepared membranes increased... 

    Compatibilization of clays and hydrophobic polymers: the case of montmorillonite and polyetheretherketone

    , Article Polymer Bulletin ; Volume 77, Issue 10 , 2020 , Pages 5505-5527 Zandsalimi, K ; Akbari, B ; Mehrnejad, F ; Bagheri, R ; Sharif University of Technology
    Springer  2020
    Abstract
    In the last three decades, nanoclay fillers have been increasingly used to improve the mechanical, thermal, barrier and biological properties of the polymers. Nevertheless, incorporation of clays into the hydrophobic polymer matrices leads to the formation of the microcomposites with the minimal improvement in properties. To overcome the intrinsic incompatibility between the clays and the hydrophobic polymers, clay particles are organophilized using organic modifiers. The organic modifier should be thermodynamically miscible with the polymer. In the case of the composites prepared at high temperatures, the organic modifier should also have a high thermal stability to withstand the processing... 

    Novel high-performance nanocomposite proton exchange membranes based on poly (ether sulfone)

    , Article Renewable Energy ; Volume 35, Issue 1 , 2010 , Pages 226-231 ; 09601481 (ISSN) Hasani-Sadrabadi, M.M ; Dashtimoghadam, E ; Ghaffarian, S.R ; Hasani Sadrabadi, M.H ; Heidari, M ; Moaddel, H ; Sharif University of Technology
    2010
    Abstract
    In the present research, proton exchange membranes based on partially sulfonated poly (ether sulfone) (S-PES) with various degrees of sulfonation were synthesized. It was found that the increasing of sulfonation degree up to 40% results in the enhancement of water uptake, ion exchange capacity and proton conductivity properties of the prepared membranes to 28.1%, 1.59 meq g -1, and 0.145 S cm -1, respectively. Afterwards, nanocomposite membranes based on S-PES (at the predetermined optimum sulfonation degree) containing various loading weights of organically treated montmorillonite (OMMT) were prepared via the solution intercalation technique. X-ray diffraction patterns revealed the... 

    Preparation of Porous PVA Nanocomposite Hydrogels Via Gamma Irradiation

    , M.Sc. Thesis Sharif University of Technology Sabourian, Parinaz (Author) ; Frounchi, Masoud (Supervisor) ; Dadbin, Susan (Supervisor)
    Abstract
    In this research, porous polyvinyl¬ alcohol (PVA)/Montmorillonite nanoclay and polyvinyl alcohol/polyvinyl pyrrolidone (PVP)/Montmorillonite nanoclay nanocomposite sponges (foams) were fabricated by freeze-drying method. The foams were crosslinked using gamma irradiation. The pore size and interconnectivity of nanocomposites characterized by scanning electron microscopy (SEM), showed bimodal pore size distribution resulting from preparation method.
    SEM micrographs displayed that addition of PVP ( wt% of total solid polymer) to the PVA sponges increased the pore size and interconnectivity, due to the optimal number of hydrogen bonds between functional groups of polymeric matrices.... 

    Preparation of Polyethersulfone/Polyamide (PES/PA)Thin Film Composite Membranes based Modified Nanoclays for Forward Osmosis-Disalination

    , M.Sc. Thesis Sharif University of Technology Veisi, Vahab (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    Abstract
    In this study, two layer nanocomposite membrane of polyethersulfone (support layer) and polyamide (active layer) were prepared for the purpose of desalination of water by forward osmosis method. In order to take more advantage of this membrane, montmorillonite nanoparticles which had been modified by graphene oxide were placed in it. To bind the nanoparticle components together, at first, montmorillonite was functionalized by (3-Aminopropyl) triethoxysilane to increase its nucleophilicity, and for graphene oxide to increase its electrophilicity, thionyl chloride was added. The two compounds were mixed and stirred for 24 hours in the presence of triethylamine base by magnetic stirrer at 30°C...