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    In vitro biocompatibility evaluations of hyperbranched polyglycerol hybrid nanostructure as a candidate for nanomedicine applications

    , Article Journal of Materials Science: Materials in Medicine ; Vol. 25, issue. 2 , 2014 , pp. 499-506 ; ISSN: 09574530 Zarrabi, A ; Shokrgozar, M. A ; Vossoughi, M ; Farokhi, M ; Sharif University of Technology
    Abstract
    In the present study, a detailed biocompatibility testing of a novel class of hybrid nanostructure based on hyperbranched polyglycerol and β-cyclodextrin is conducted. This highly water soluble nanostructure with size of less than 10 nm, polydispersity of less than 1.3, chemical tenability and highly branched architecture with the control over branching structure could be potentially used as a carrier in drug delivery systems. To this end, extensive studies in vitro and in vivo conditions have to be demonstrated. The in vitro studies include in vitro cytotoxicity tests; MTT and Neutral Red assay as an indicator of mitochondrial and lysosomal function, and blood biocompatibility tests such as... 

    Boric acid/glycerol as an efficient catalyst for regioselective epoxide ring opening by aromatic amines in water

    , Article Green Chemistry Letters and Reviews ; Volume 5, Issue 1 , 2012 , Pages 1-5 ; 17518253 (ISSN) Halimehjani, A. Z ; Gholami, H ; Saidi, M. R ; Sharif University of Technology
    Abstract
    Regioselective epoxides ring opening with aromatic amines using boric acid and glycerol in water as a green media have been investigated. Corresponding β-amino alcohols were obtained with excellent yields and considerable regioselectivity. High yields of the products and mild reaction conditions using green catalyst and water as a green solvent are some advantages of this procedure  

    Separation of carbon dioxide by potassium carbonate based supported deep eutectic liquid membranes: influence of hydrogen bond donor

    , Article Journal of Membrane Science and Research ; Volume 8, Issue 1 , 2022 ; 24765406 (ISSN) Saeed, U ; Khan, A. U ; Khan, A. L ; Gilani, M. A ; Bilad, M. R ; Sharif University of Technology
    Amirkabir University of Technology - Membrane Processes Research Laboratory  2022
    Abstract
    This article focuses on the study of potassium carbonate (PC) based deep eutectic solvents based supported liquid membranes (DES-SLMs) for CO2 separation. Two types of DESs were synthesized by mixing and subsequently heating PC with glycerol or ethylene glycol separately. The mechanism of interaction was inferred from the spectral analysis (FTIR) whereas thermal study (TGA) was performed to analyze the stability of the membrane. Experiments were carried out to analyze the permeability and separation factor of the membranes. The PC-Glycerol based SLM reported permeability of 34 Barrer and ideal selectivity of 59 while PC-Ethylene Glycol based SLM showed permeability of 20 Barrer and... 

    Lipase catalyzed incorporation of conjugated linoleic acid by transesterification into sunflower oil applying immobilized lipase (Lipozyme TL IM and RM IM)

    , Article International Journal of Engineering, Transactions A: Basics ; Volume 29, Issue 4 , 2016 , Pages 436-443 ; 17281431 (ISSN) Kouchak Yazdi, Z ; Alemzadeh, I ; Sharif University of Technology
    Abstract
    Conjugated Linoleic Acid (CLA), Glycerol (G) and sunflower oil blends with varying concentration were subjected to enzymatic esterification using a 1, 3-specific immobilized lipase. CLA was used as acyl due to its purported health benefits. The transesterified lipids were evaluated for free fatty acids (FFA) and composition of fatty acids by gas chromatography. Lipozyme RM IM is preferred for enzymatic esterification because of more CLA incorporation and less free fatty acids at the end of reaction than Lipozyme TL IM. Response surface methodology (RSM) was used to determine the effects of three variables Glycerol concentration, reaction temperature, and amount of enzyme on the lipase... 

    Developing a mathematical model for reforming of glycerol towards a comparative evaluation of the liquid vs. gas phase medium

    , Article International Journal of Hydrogen Energy ; Volume 44, Issue 49 , 2019 , Pages 26764-26772 ; 03603199 (ISSN) Nayernia, Z ; Kazemeini, M ; Larimi, A ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Glycerol might be converted into hydrogen through a catalytic reforming process. In order to design an effective route, the choice of reaction conditions and in particular its medium considered yet a crucial issue still needing further investigations. In this research, a mathematical model of reforming processes in vapor (i.e., steam reforming (SR) and liquid phase (i.e.; aqueous phase reforming (APR)) were developed. This was performed in terms of understudying effects of parameters including the reactor diameter, catalyst morphology (i.e., particle size) and mass flow rate on the glycerol conversion. Then, a superior reaction medium in terms of these variables was determined. For data... 

    Renewable hydrogen production over Pt/Al₂O₃ nano-catalysts: Effect of M-promoting (M=Pd, Rh, Re, Ru, Ir, Cr)

    , Article International Journal of Hydrogen Energy ; Volume 44, Issue 16 , 2019 , Pages 8243-8251 ; 03603199 (ISSN) Larimi, A ; Khorasheh, F ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Xwt% Pt/Al 2 O 3 (X = 1, 3, 5, 8, 10) and 5 wt% Pt-1wt% M/AlO 3 (M = Pd, Rh, Re, Ru, Ir, Cr) catalysts were prepared, characterized and tested for aqueous phase reforming of pure and crude glycerol. Results show drastic dependence of catalytic performance of catalysts on both the active metal loading and the type of applied promoters. 5 wt% was the best Pt loading and Pt[sbnd]Rh/Al₂O₃ shows the best catalytic activity which has the highest hydrogen production rate (mmol/g cat h −1 ) and selectivity (89%) in continuous aqueous phase reforming of 10 wt% pure glycerol solution  

    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... 

    Comparative process modeling and techno-economic evaluation of renewable hydrogen production by glycerol reforming in aqueous and gaseous phases

    , Article Energy Conversion and Management ; Volume 225 , December , 2020 Khodabandehloo, M ; Larimi, A ; Khorasheh, F ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    In this paper, a comparative techno-economic evaluation of hydrogen production by glycerol reforming in aqueous and gaseous phases are presented. To accomplish the techno-economic evaluation, firstly the process modeling and design are presented. Based on the equipment purchased costs, with 80 kg/h hydrogen production, the total cost of hydrogen production is estimated 3.65 and 3.55 $/kgH2 for steam reforming and aqueous phase reforming plants, respectively. Regarding the installation factor in the equipment costs, the total cost of hydrogen production is estimated 7.49 and 7.45 $/kgH2 for steam reforming and aqueous phase reforming plants, respectively. To investigate the impact of... 

    Catalytic conversion of bio-renewable glycerol to pure hydrogen and syngas: Energy management and mitigation of environmental pollution

    , Article Energy Conversion and Management ; Volume 247 , 2021 ; 01968904 (ISSN) Khademi, M.H ; Lotfi Varnoosfaderani, M ; Moghadasin, M. H ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Hydrogen and syngas, as two effective clean fuels, have a considerable stake in the global fuel market. These are dominantly produced from fossil fuels through reforming processes, which lose a large amount of energy and emit numerous amounts of CO2. Bio-renewable glycerol steam reforming is an attractive alternative to traditional reforming for reducing the dependence on hydrocarbon resources and mitigating climate change. This research aims to manage a heat-integrated reactor with three concentric cylinders, containing exothermic-side (methane tri-reforming), endothermic-side (glycerol steam reforming), and permeation-side for co-production of pure hydrogen and syngas. In this process,... 

    Hydrogen Production by Aqueous Phase reforming of Glycerol Over Supported Platinum Catalysts

    , Ph.D. Dissertation Sharif University of Technology Larimi, Afsaneh Sadat (Author) ; Kazemeini, Mohammad (Supervisor) ; Mohammadi, Ali Asghar (Supervisor)
    Abstract
    The aqueous phase reforming (APR) of glycerol is an attractive yet challenging pathway to convert abundant biomass into value added hydrogen. Pt catalysts have received attention due to their ability to produce hydrogen-rich gas under APR conditions. In this work, the conversion of glycerol into hydrogen is demonstrated using Pt0.05CexZr0.95-xO2 (x=0, 0.29, 0.475, 0.66 and 0.95) solid solution catalysts and a series of M-doped Pt-MgO (M = Pd, Ir, Re, Ru, Rh and Cr) sheet-shaped nano-catalysts. Both characteristic (XRD, BET, H2-TPR, CO-chemisorption, TEM and XPS) and reactivity measurements were used to investigate the activity of the catalysts. Results indicated that reactivity depended on... 

    Production of renewable hydrogen through aqueous-phase reforming of glycerol over Ni/Al2O3–MgO nano-catalyst

    , Article International Journal of Hydrogen Energy ; Volume 43, Issue 2 , 2018 , Pages 614-621 ; 03603199 (ISSN) Bastan, F ; Kazemeini, M ; Larimi, A ; Maleki, H ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    In this study, a series of Ni nano-catalysts supported on Al2O3 and MgO were prepared through the co-precipitation technique. Effects of the Al/Mg ratio on physicochemical characteristics of Ni/Al2O3–MgO catalysts were examined. Moreover, catalytic performance was investigated in order to determine the optimum catalyst for H2 production in aqueous phase reforming (APR) of glycerol. It was revealed that, the APR activity of synthesized catalysts strongly depended on the aforementioned ratio. In addition, it was observed that, the catalytic activity of Ni/MgO and Ni/Al2O3 samples were both lower than that of the corresponding mixed oxide supports. Furthermore, it was shown that, amongst the... 

    Sustainable ammonia production from steam reforming of biomass-derived glycerol in a heat-integrated intensified process: Modeling and feasibility study

    , Article Journal of Cleaner Production ; Volume 324 , 2021 ; 09596526 (ISSN) Khademi, M. H ; Lotfi Varnoosfaderani, M ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Currently, ammonia, as a clean and sustainable energy carrier, is intensively synthesized from its elements during the Haber-Bosch technology. This process requires a large amount of energy and emits numerous amounts of carbon dioxide, because hydrogen is dominantly produced from fossil fuels through reforming processes. Biomass-derived glycerol steam reforming is an attractive alternative to traditional reforming for reducing the dependence on hydrocarbon resources and mitigating climate change. This research aims to intensify a heat-integrated process for the co-production of ammonia and syngas from glycerol valorization. In this process, glycerol reforming continuously provides hydrogen... 

    Use of biomass-derived glycerol as an alternative to fossil fuels for aniline production: Energy saving and environmental aspects

    , Article Fuel ; Volume 310 , 2022 ; 00162361 (ISSN) Khademi, M. H ; Lotfi-Varnoosfaderani, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Catalytic reduction of nitrobenzene is the leading technological step in aniline production. The hydrogen required for this stage, is dominantly produced from fossil fuels through reforming processes, which take much energy and emit large amounts of CO2. Biomass-derived glycerol steam reforming is an attractive alternative to traditional reforming to reduce the dependence on hydrocarbon resources and mitigate climate change. This research aims to analyze a mass- and heat-integrated multi-tubular membrane reactor, containing nitrobenzene hydrogenation (exothermic-side) and glycerol steam reforming (endothermic-side) for co-production of aniline and syngas. In this process, hydrogenation... 

    CO2/N2 Mixed Gas Separation in Glycerol Liquid Membrane Containing Sodium Carbonate Carriers

    , M.Sc. Thesis Sharif University of Technology Haghighat, Parsa (Author) ; Bastani, Darush (Supervisor)
    Abstract
    In this research, initially the Glycerol liquid membrane with dissolved sodium carbonate carriers, which is supported by CA porous filter, was prepared. The effects of Na2CO3 concentration and pressure difference on gas permeability were investigated. Permeability of CO2 and N2 were measured at pressure difference of 0.7, 1.6, 2.1 and 2.8 bar with carbonate sodium concentration of 0, 1 and 2 mol/lit. Permeability of CO2 was found to be higher than N2. Increasing the pressure difference resulted in an increase in the N2 permeability coefficient while decreased the CO2 permeability coefficient. Increasing the concentration of sodium carbonate increased the CO2 permeability drastically but... 

    Kinetic Modeling of Glycerol Aqueous Phase Reforming Process

    , M.Sc. Thesis Sharif University of Technology Nayernia, Zahra (Author) ; Kazemeini, Mohammad (Supervisor)
    Abstract
    Dwindling fossil fuel reserves with attendant rising crude oil price and the relatively rapid growth in global population have made the search for sustainable energy supply more imperative. Among the various renewable resources, biomass has attract much more attention. Glycerol as the major by-product of the biodiesel production process, can be converted to hydrogen. One of the methods for converting glycerol to hydrogen is aqueous phase reforming (APR). In the current research, glycerol aqueous phase reforming is modeled and then simulated with MATLAB software. The reactor diameter is 5 mm and its length is 20 cm and reactor operated at 250℃ and 50 bar. Glycerol conversion obtained is... 

    Production of Lactic Acid from Glycerol in Microchannel Reactors in the Presence of Copper-Based Catalysts

    , M.Sc. Thesis Sharif University of Technology Jalal Sahandi, Pooya (Author) ; Kazemeini, Mohammad (Supervisor) ; Sadjadi, Samaheh (Supervisor)
    Abstract
    Hand in hand with the flourish of the biodiesel industries, glycerol has turned into an abundant waste chemical posing obstacles to their large-scale implementation. Devising measures for efficient transformation of glycerol into value added products is a promising alternative to its large-scale disposal into the nature that would also increase the competitiveness of biodiesel fuels. In this study, production of lactic acid (LA) as a valuable chemical with wide applicability is studied in a continuous process with glycerol as a cheap and convenient feedstock. In this regard, the state-of-the-art approaches in catalytic conversion of glycerol to LA are reviewed. A catalytic method using... 

    Novel approach for liquid-liquid phase equilibrium of biodiesel (canola and sunflower) + glycerol + methanol

    , Article Industrial and Engineering Chemistry Research ; Vol. 53, issue. 2 , 2014 , pp. 855-864 ; ISSN: 08885885 Hakim, M ; Abedini Najafabadi, H ; Pazuki, G ; Vossoughi, M ; Sharif University of Technology
    Abstract
    In this study, a novel experimental approach was used to overcome the lack of phase equilibrium information to obtain data that is more applicable to industrial situations. Liquid-liquid equilibrium (LLE) data, tie-lines, and phase boundaries were carried out for two systems of canola oil methyl esters (containing 1 wt % KOH) + glycerol + methanol and sunflower oil methyl esters (containing 1 wt % KOH) + glycerol + methanol at three different temperatures (303.15, 313.15, and 323.15 K). The quality of data was also ascertained using Othmer-Tobias correlations. The experimental LLE data was also correlated by the nonrandom two-liquid (NRTL) and the Wilson-NRF Gibbs free energy models. The... 

    Fully supramolecular vesicles as anticancer drug delivery systems

    , Article New Journal of Chemistry ; Volume 37, Issue 2 , 2013 , Pages 295-298 ; 11440546 (ISSN) Pourjavadi, A ; Adeli, M ; Yazdi, M ; Sharif University of Technology
    2013
    Abstract
    A supramolecular linear-dendritic copolymer consisting of a polystyrene backbone and hanging hyperbranched polyglycerols was prepared and characterized. Host-guest interactions between β-cyclodextrin incorporated in the core of polyglycerol as a host and aromatic rings of polystyrene as guests lead to the formation of a supramolecular linear-dendritic copolymer. Supramolecules formed micelles in aqueous solutions which were able to encapsulate and transfer paclitaxel with a high loading capacity  

    Effect of different lubricant on microstructure of second cold rolled silicon steel used in transformer core

    , Article Proceedings of the 10th International Conference on Steel Rolling, 15 September 2010 through 17 September 2010, Beijing ; 2010 ; 9787502453596 (ISBN) Eftekhari, S. A ; Akbarzade, A ; Mirahmadi Khaki, D ; Aminnejad, F ; Sharif University of Technology
    2010
    Abstract
    One of the important parts of each transformer is core. It is made from multilayer silicon steel sheets. Silicon steel has high magnetic permission, high electrical resistance and minimum hysterics loss. In different metal forming process, lubrication is done for reducing friction effects. In this research, effect of 3 different type lubricants, mineral material (castor oil), organic material (glycerol), and semi organic material (paraffin) with and without additive (graphite) is investigated. Also, effect of 2 industrial lubricants (suds and motor oil) is compromised with above lubricants. Results show the best lubricant for second cold rolling of silicon steel is semi organic (paraffin)... 

    Highly selective doped Pt[sbnd]MgO nano-sheets for renewable hydrogen production from APR of glycerol

    , Article International Journal of Hydrogen Energy ; Volume 41, Issue 39 , 2016 , Pages 17390-17398 ; 03603199 (ISSN) Larimi, A. S ; Kazemeini, M ; Khorasheh, F ; Sharif University of Technology
    Elsevier Ltd  2016
    Abstract
    A series of M-doped Pt[sbnd]MgO (M = Pd, Ir, Re, Ru, Rh and Cr) sheet-shaped nano-catalysts were synthesized by the controlled co-precipitation method. The effects of M-doping on both the physicochemical and the chemisorption characteristics of Pt[sbnd]MgO catalysts were examined. The performance of the catalysts for the aqueous phase reforming (APR) of glycerol was also investigated. The APR activity of Pt[sbnd]M[sbnd]MgO catalysts depended on the type of the M dopant used. The APR activity varied in the following order: Rh > Pd > Cr > Ir > undoped ≈ Ru > Re, with the Rh-promoted catalyst having an activity of about one order of magnitude higher than the Re-promoted catalyst at 250 °C. It...