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    Manufacturing and Investigating of Nano carbon/Polyethylene Nanocomposites via In-situ Polymerization

    , M.Sc. Thesis Sharif University of Technology Sadrani, Alaleh (Author) ; Ramezani Saadatabdi, Ahmad (Supervisor)
    Abstract
    In this research UHMWPE/CB nanocomposites were prepared via in situ polymerization using Bi-supported Ziegler-Natta catalytic systems. Magnesium etoxide and carbon black were used as supports of catalyst. TiCl4 accompanied by triisobutyl aluminum and diisobutyl phthalate (DIBP) constituted Ziegler-Natta catalytic system. Preparation of catalyst and polymerization were done in slurry phase under the argon atmosphere. Then, structural, thermal and mechanical properties of produced nanocomposites with different CB content were evaluated by SEM, DSC, TGA, DMTA and tensile tests. Scanning Electron Microscopy (SEM) images also certified very good dispersion of CBs throughout PE matrix.... 

    In-situ preparation and characterization of ultra-high molecular weight polyethylene/diamond nanocomposites using bi-supported Ziegler-Natta catalyst: effect of nanodiamond silanization

    , Article Materials Today Communications ; Volume 14 , March , 2018 , Pages 53-64 ; 23524928 (ISSN) Haddadi, S. A ; Ramezani Saadatabadi, Ahmad ; Amini, M ; Kheradmand, A ; Shsrif University of Technology
    Elsevier Ltd  2018
    Abstract
    In this study, reinforcement of ultra-high molecular weight polyethylene (UHMWPE) was investigated using the sol-gel surface modified diamond nanoparticles (NDs). Nanocomposite samples were synthesized via in-situ polymerization using bi-supported Ziegler-Natta catalyst. Fourier transform infrared spectroscopy, thermogravimetric analysis and contact angle measurements proved the proper silanization (∼1.9%) of NDs. Characterization of the catalysts revealed decrease in the activity of catalysts in presence of NDs which were responsible for the lower average molecular weight of the samples. Field emission scanning electron microscopy revealed an improved dispersion of the modified NDs in... 

    Investigation of auto ignition condition under different parameters

    , Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 27, Issue 2 , 2008 , Pages 93-101 ; 10219986 (ISSN) Razzaghi, S ; Kharrat, R ; Rashtchian, D ; Vossoughi, S ; Saraji, S ; Sharif University of Technology
    2008
    Abstract
    In this work, the potential of auto-ignition of heavy oil during in-situ combustion (ISC) process was studied. Kinetic studies were carried out using Thermo Gravimetric Analyzer (TGA), Differential Scanning Calorimetry (DSC) and Accelerating Rate Calorimetric (ARC) techniques. Effects of oxygen partial pressure, reservoir pressure and clay on auto ignition condition were investigated on a number of different heavy oil samples from south west Iran mixed with silica sand or crushed carbonate rock and clay. Based on the experimental results obtained by TGA runs, the kinetic equation was derived for different oil samples in the presence of different sands. Effect of partial pressure of oxygen in... 

    In-situ Pb2+ remediation using nano iron particles

    , Article Journal of Environmental Health Science and Engineering ; Volume 13, Issue 1 , 2015 ; 2052336X (ISSN) Fadaei Tehrani, M. R ; Shamsai, A ; Vossughi, M ; Sharif University of Technology
    BioMed Central Ltd  2015
    Abstract
    Originally, application of nano zero valent iron (nZVI) particles for the removal of lead (Pb2+) in porous media was studied. At first, stabilized nZVI (S-nZVI) was prepared and characterized, then used in batch and continuous systems. Based on the batch experiments, corresponding reaction kinetics well fitted with the pseudo-first-order adsorption model, and reaction rate ranged from 0.01 to 0.04 g/mg/min depend on solution pH and the molar ratio between Fe and Pb. In batch tests, optimal condition with more than 90% removal efficiency at 60 min was observed at a pH range of 4 to 6 and Fe/Pb ratio more than 2.5. Continuous experiments exposed that Pb2+ remediation was as well influenced by... 

    Investigation Properties of Polyethylene/ Carbon Nanotube Nanocomposites Prepared Via in Situ Polymerization

    , M.Sc. Thesis Sharif University of Technology Meschi Amoli, Behnam (Author) ; Ramazani Saadatabadi, Ahmad (Supervisor)
    Abstract
    In this research UHMWPE/MWCNT nanocomposites with different concentrations of nanotubes (0.5, 1.5, 2.5, 3.5 wt %) were prepared via in situ polymerization using a novel Bi-supported Ziegler-Natta catalytic systems. Magnesium etoxide and Multi wall carbon nanotubes functionalized by hydroxyl groups were used as supports of catalyst. TiCl4 accompanied by triethylaluminum constituted Ziegler-Natta catalytic system. Preparation of catalyst and polymerization were done in slurry phase under the argon atmosphere. Support of catalyst on MWCNT was investigated using Fourier Transform Infrared Spectroscopy (FTIR). The results confirmed interaction between catalyst and hydroxyl groups on the surface... 

    Manufacturing and Investigation the Properties of Polyethylene/ Fumed Silica Nanocomposites Via in situ Polymerization

    , M.Sc. Thesis Sharif University of Technology Ghahri Saremi, Maysam (Author) ; Ramazani Saadatabadi, Ahmad (Supervisor)
    Abstract
    In this research UHMWPE/FUMED SILICA nanocomposites with different concentrations of nano fumed silica (0.5, 1.5, 2.5, 4.5 wt %) were prepared via in situ polymerization using a novel Bi-supported Ziegler-Natta catalytic systems. Magnesium etoxide and Fumed Silica functionalized by hydroxyl groups were used as supports of catalyst. TiCl4 accompanied by triethylaluminum constituted Ziegler-Natta catalytic system. Preparation of catalyst and polymerization were done in slurry phase under the argon atmosphere. Scanning Electron Microscopy (SEM) images also certified very good dispersion of fumed silica throughout PE matrix. Intrinsic viscosity measurements showed high molecular weight for... 

    Preparation and Investigating of Polyolephine/graphene Oxide Nanocomposites Via In-situ Ziegler-natta Polymerization

    , M.Sc. Thesis Sharif University of Technology Bahrami, Hiva (Author) ; Ramazani Saadatabadi, Ahmad (Supervisor)
    Abstract
    The main object of this thesis is preparation and investigation of polyolophine/graphene oxide nanocomposites by using bi-supported Ziegler-Natta catalytic system and in-situ polymerization. Magnesium ethoxide and graphene oxide were used as supports of catalyst. TiCl4 was accompanied by triisobutyl aluminum (tibia) and diisobutyl phthalate (DIBP) as an electron donor constituting Ziegler-Natta catalytic system. Preparation of catalyst and polymerization were taken place in slurry phase under the argon atmosphere. At the beginning of the polymerization experiment, several type of nanocomposites were made under various conditions (such as different Al/Ti molar ratio) to find optimum condition... 

    Preparation of Cu-TiC Nanocomposite and Investigation of Microstructure, physical and Mechanical Properties

    , M.Sc. Thesis Sharif University of Technology Bagheri, Gholamali (Author) ; Pourazarang, Kazem (Supervisor) ; Abachi, Parvin (Co-Advisor)
    Abstract
    In this study, Cu-TiC nanocomposites were produced by high energy ball milling of elemental powders and in situ formation of TiC in the copper base. Cu and 5,10,20 and 40 wt% Ti powder blend were milled for 60 h, then graphite powders were added and milling was continued for 10 h again and Finally Cu-TiC composite powders with 10.68, 20.16, 36.24 and 60.25 vol% of reinforcements (6.18, 12.2, 23.82 and 45.47 wt%) were produced. The effect of time on the solution of titanium in the copper was studied by X-Ray diffraction analysis (XRD). crystallite size and lattice strain of copper were determined 12nm and 1.04% subsequently for Cu-40wt%TiC after 60 h milling. to ensure the formation of... 

    Preparation of conductive polyaniline/graphene nanocomposites via in situ emulsion polymerization and product characterization

    , Article Synthetic Metals ; Vol. 196 , 2014 , pp. 199-205 Baniasadi, H ; Ramazani, S. A ; Mashayekhan, S ; Ghaderinezhad, F ; Sharif University of Technology
    Abstract
    This work, which is a part of our ongoing studies on developing conductive scaffolds for nerve tissue engineering, reports synthesis of highly conductive binary-doped polyaniline nanoparticles and polyaniline/graphene nanocomposites. The samples were synthesized through chemical oxidation of aniline via in situ emulsion polymerization method in presence of hydrochloric acid and sodium dodecyl sulfate. Graphene nanosheets were also prepared via modified Hummer's method followed by chemical reduction using hydrazine monohydrate. Electrical conductivity measurements using a standard four-point probe technique with FTIR and UV-vis studies revealed that conductive binary-doped emeraldine salt... 

    Feasibility study of auto ignition in in-situ combustion process

    , Article Journal of the Japan Petroleum Institute ; Volume 51, Issue 5 , 2008 , Pages 287-297 ; 13468804 (ISSN) Razzaghi, S ; Kharrat, R ; Vossoughi, S ; Rashtchian, D ; Sharif University of Technology
    2008
    Abstract
    Air injection, and the resulting in-situ combustion process, utilizes an inexpensive injectant, air, to accelerate oil recovery and increase reserves. The potential of auto ignition of heavy oil during in situ combustion process was studied in KEM reservoir. The risk of carbonate decomposition due to high temperature was examined. The carbonate rock decomposition was taken at 650°C. The peak of low temperature combustion by producing CO was initiated at 275°C when air was injected. There was no risk of decomposition of the carbonate Sarvak formation due to high temperatures of the process. Enrichment of the injecting fluid by oxygen increased the possibility of ignition. Ignition occurred... 

    Fabrication of Al Based Nanocomposite with Al2O3 and Al3Ti Reinforcements by Mechanical Milling and Press and Sintering (In situ method) and Investigation of Its Wear Behavior

    , M.Sc. Thesis Sharif University of Technology Shabani Nezhad, Parisa (Author) ; Seyed Reihani, M (Supervisor)
    Abstract
    In this study, Aluminium based nanocomposite with Al3Ti and Al2O3 nanoparticles have been elaborated by mechanical alloying. For this purpose, Al and TiO2 powders have been blended with weight ratios of 10, 20 and 30 percents and were milled using a planetary mill. Morphological variations in different timing periods of mechanical milling process was investigated by Scaning Electron Microscopy (SEM) and The optimal times for alloying were determined for each combination. The pure Aluminium and the powder with 10, 20 and 30%wt reinforcement had coax morphology after respectively for 44, 30, 24 and 14 hours. after studing phase transformations by XRD analysis, the final powders were cold... 

    Investigation of Production Increasing in In-situ Preparation of Polyolefin/clay Nanocomposites

    , M.Sc. Thesis Sharif University of Technology Javan Nikkhah, Sousa (Author) ; Ramazani Saadat Abadi, Ahmad (Supervisor)
    Abstract
    This project is devoted to experimental investigation of increasing on production of polyethylene/clay nanocomposites (PECNs) and polypropylene/clay nanocomposites (PPCNs) via in-situ polymerization method. First of all we produced bi-supported Ziegler-Natta catalyst to polymerized polyolefins nanocomposites. Bentonite type clay and Magnesiumethoxide (Mg (OEt)2) were used as the support of Tetrachloridetitanium (TiCl4). Catalyst support and polymerization process have been done in slurry phase using Triisobutylaluminum (TiBA) as the co-catalyst. The efficiency of preapared bi-supported Ziegler-Natta was reasonably high (average 200 (gr. Product/mmol Ti. h) for PECNs and 195 (gr. Product/mmol... 

    Synthesis of Mg / MgO - Mg2Cu by in-situ Reaction Method and Investigation on Structure and Mechanical Properties

    , M.Sc. Thesis Sharif University of Technology Hemati Kia, Mohammad (Author) ; Abachi, Parvin (Supervisor) ; Salahi, Esmaeil (Supervisor) ; Pour Azarang, Kazem (Co-Advisor)
    Abstract
    In this project formation of MgO & Mg2Cu reinforcement particle in Magnesium matrix was investigated. Firstly Mg & CuO powders mixture in different weight percentage (4, 8%wt CuO) in 20:1 and 30:1 BPR were milled. Finally, according to XRD result 30:1 BPR was selected for milling. Variations in powders morphology, particles size, crystallite size, lattice strain and phase transformation were investigated by X-ray diffraction, scanning electron microscopy and laser particle size analyzer in different milling time. Result showed that during reaction between Mg and CuO, MgO & Mg2Cu reinforcement particles were formed in matrix. Matrix crystallite size was determined about 35-40 nm. Mg-6.3%wt Cu... 

    Comparison of Mechanical Properties of Al-TiB2 Composite in as Cast, Heat Treated and Extruded Condition

    , M.Sc. Thesis Sharif University of Technology Khodabakhsh Pirkalani, Maryam (Author) ; Varahram, Naser (Supervisor) ; Davami, Parviz (Supervisor)
    Abstract
    This research focused on mechanical properties of Al-TiB2 composite in as cast, heat treated and extruded condition. The composites were produced by mixing Al-Ti and Al-B master alloyes. Since some engineering parts during service are supposed to tolerate severe wear conditions, in this research abrasive wear condition was wxamined using pin on disk method. In a fixed load and abrasive disk, composites showed better resistance against wear in comparison with matrix alloy. Furtheremore, T6 heat treatment made composites more resistant against abrasive wear. Finally the best wear resistance was accompolished when composite was extruded and then heat treated. While increase in reinforcement... 

    Manufacturing and Investigating of Polypropylene/Silica Nanocomposites via in-situ Polymerization and Using Bi-supported Ziegler-Natta Catalyst

    , M.Sc. Thesis Sharif University of Technology Azinfar, Bahareh (Author) ; Ramezani Saadat, Ahmad (Supervisor)
    Abstract
    The main object of this thesis is production and investigation of polypropylene-fumed silica nanocomposites by using bi-supported Ziegler-natta catalytic system and in-situ polymerization. Magnesium ethoxide and fumed silica were used as supports of catalyst. TiCl4 was accompanied by triisobutyl aluminum(TiBA) and diisobutyl phthalate(DIBP) as electron doner constituting Ziegler-Natta catalytic system. Preparation of catalyst and polymerization were taken place in slurry phase under the argon atmosphere. At the beginning of the polymerization experiment, several type of nanocomposites were made under various conditions(such as different Al/Ti molar ratio) to find optimum condition to... 

    The effect of Li on the tensile properties of cast Al-Mg2Si metal matrix composite

    , Article Materials Science and Engineering A ; Volume 490, Issue 1-2 , 2008 , Pages 250-257 ; 09215093 (ISSN) Hadian, R ; Emamy, M ; Varahram, N ; Nemati, N ; Sharif University of Technology
    2008
    Abstract
    The effects of both Li modification and cooling rate on the microstructure and tensile properties of an in situ prepared Al-15%Mg2Si composite were investigated. It was found that the addition of 0.3%Li reduces the average size of Mg2Si primary particles from ∼30 to ∼6 μm. The effect of cooling rate was investigated by the use of a mold with different section test bars. The results showed an increase in both UTS and elongation values with reduction in section thicknesses corresponding to increasing cooling rates. Adding Li also raised the tensile strength and elongation values and reduced the number of decohered particles observed in fracture surfaces thereby increasing the alloy's... 

    The effect of fractures' geometrical properties on the recovery mechanism of the top-down in situ combustion process

    , Article Petroleum Science and Technology ; Volume 30, Issue 2 , Feb , 2011 , Pages 147-158 ; 10916466 (ISSN) Fatemi, S. M ; Kharrat, R ; Sharif University of Technology
    2011
    Abstract
    The top-down in situ combustion (ISC) involves the stable propagation of the combustion front from the top vertical injector to the bottom horizontal producer. Apart from laboratory studies in conventional sandstones, no application of the process in fractured carbonates has been addressed yet. The authors modified a successful combustion tube history matched model of an Iranian low-permeable heavy oil reservoir called Kuh-E-Mond to investigate the feasibility of ISC in fractured carbonate reservoirs mimicking block-scale combustion cells. Effects of fractured geometrical properties such as orientation, location, extension, density, spacing, and dispersion were considered. Results confirmed... 

    In situ emulsion polymerization and characterization of PVAc nanocomposites including colloidal silica nanoparticles for wood specimens bonding

    , Article Journal of Applied Polymer Science ; Volume 137, Issue 15 , 2020 Azamian Jazi, M ; Ramezani Saadat Abadi, A ; Haddadi, S. A ; Ghaderi, S ; Azamian, F ; Sharif University of Technology
    John Wiley and Sons Inc  2020
    Abstract
    Polyvinyl acetate (PVAc) nanocomposites for wood adhesives containing different amounts of colloidal silica nanoparticles (CSNs) were synthesized via in situ one-step emulsion polymerization. The adhesion strength of wood specimens bonded by PVAc nanocomposites was investigated by the tensile test. Thermal properties of PVAc nanocomposites were also characterized by differential scanning calorimetry and thermogravimetric analysis. Rheological and morphological properties of the PVAc nanocomposites were investigated using rheometric mechanical spectrometry and field emission scanning electron microscopy (FESEM), respectively. The obtaining results showed that the shear strength of PVAc... 

    Fully implicit compositional thermal simulator using rigorous multiphase calculations

    , Article Scientia Iranica ; Volume 18, Issue 3 C , June , 2011 , Pages 509-517 ; 10263098 (ISSN) Khorsandi Kouhanestani, S ; Bozorgmehry Boozarjomehry, R ; Pishvaie, M. R ; Sharif University of Technology
    2011
    Abstract
    Simulation of the in-situ combustion process is one of the most complex simulations amongst other reservoir flow simulations. Accurate simulation of the process is critical to obtain a successful implementation of the in-situ combustion process. Several factors impact performance of the simulation of this process. First are all the numerical models used for different sub-processes, such as reactions, fluid phase behavior, heat loss to surrounding formations and fluid physical properties. In the previous numerical models of the in-situ combustion process, very simplified models were used for the phase behavior of the fluid. Recent studies show that the fluid phase behavior model has a great... 

    A new semi-analytical modeling of steam-assisted gravity drainage in heavy oil reservoirs

    , Article Journal of Petroleum Science and Engineering ; Volume 69, Issue 3-4 , 2009 , Pages 261-270 ; 09204105 (ISSN) Alali, N ; Pishvaie, M. R ; Jabbari, H ; Sharif University of Technology
    Abstract
    Thermal recovery by steam injection has proven to be an effective means of recovering heavy oil. Forecasts of reservoir response to the application of steam are necessary before starting a steam drive project. Thermal numerical models are available to provide forecasts. However, these models are expensive and consume a great deal of computer time. An alternative to numerical modeling is to use a semi-analytical model. The objective of the current study was to investigate thermal applications of horizontal wells for displacement and gravity drainage processes using analytical modeling as well as reservoir simulation. The main novelties presented in the paper are: a) the transient temperature...