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    Phase morphology of polyblends of amorphous polycarbonate and semi-crystalline polyethylene terephthalate

    , Article Iranian Polymer Journal (English Edition) ; Volume 11, Issue 3 , 2002 , Pages 151-157+209 ; 10261265 (ISSN) Frounchi, M ; Mehrabzadeh, M ; Mohseni, S. S ; Sharif University of Technology
    2002
    Abstract
    Phase morphology, state of compatibility and various properties of blends of polycarbonate (PC) with bottle-grade and fibre-grade polyethylene terephthalate (BPET and FPET, respectively) were investigated. It was found that these blends have two-phase separated morphology with partial miscibility. Scanning electron micrographs revealed separated domains of PC-rich and PET-rich zones. PC domains appear spherical increasing in size from 2 μm for PC20/FPET80 up to about 5 μm for PC60/FPET40 blend. Further increase in PC content up to 80% caused phase inversion in which FPET appears as finely dispersed domains in continuous PC matrix. Tg of PC-rich phase decreased from 153 deg;C for pure PC down... 

    Preparation and characterization of polycarbonate/thermoplastic polyurethane blend membranes for wastewater filtration

    , Article Journal of Water Process Engineering ; Volume 16 , 2017 , Pages 170-182 ; 22147144 (ISSN) Nazemidashtarjandi, S ; Mousavi, S. A ; Bastani, D ; Sharif University of Technology
    Elsevier Ltd  2017
    Abstract
    The polycarbonate (PC)/thermoplastic polyurethane (TPU) blend membranes were prepared by phase inversion process applied to membrane bioreactor (MBR) to investigate the fouling characteristics. The impact of TPU and poly (vinylpyrrolidone) PVP concentration in polymer dopes on membrane structure, morphology, and performance were studied. The flat sheet fabricated membranes were characterized by scanning electron microscope (SEM), water contact angle (WCA), membrane surface roughness measurements and mechanical strength. The membrane performance was investigated at subcritical operating conditions. Pure water and critical flux through the fabricated membranes were measured for better... 

    An optical study of cobalt nanowires dispersed in liquid phase

    , Article Optics Communications ; Volume 274, Issue 2 , 2007 , Pages 471-476 ; 00304018 (ISSN) Azarian, A ; Iraji zad, A ; Dolati, A ; Sharif University of Technology
    2007
    Abstract
    The Co nanowires were electrodeposited in polycarbonate membrane (PCT). SEM, TEM and XPS techniques were used to characterize the morphology, structure and size of nanowires as well as chemical composition. The influence of different mediums was studied on the optical absorption of dispersed cobalt nanowires. The absorption spectrum of cobalt nanowires in water showed a broad shoulder at 290 nm, but in ethanol solution it was not observed in the visible region of the spectra up to 200 nm. Cobalt nanowires dispersed in methanol presented a peak at 236 nm. We attribute the data to oxidation of cobalt in water and low dielectric constant of methanol relative to ethanol and water. We found... 

    Synthesis of Palladium Nanowires for Hydrogen Gas Sensor by Field Ionization

    , M.Sc. Thesis Sharif University of Technology dolatkhah, Naeme (Author) ; Irajizad, Azam (Supervisor)
    Abstract
    The interesting properties of metallic nanowires provide many applications in electronic sensors. In this project, we have synthesized Pd nanowires using electrodeposition method. These nanowires are useful for hydrogen sensors by measuring field ionization current in gas. In this project, Pd nanowires were synthesized by electrochemical deposition method in PCT template with 100 nm pore size. The used solution was contained 2mM PdCl2 + 0.1M HCl. The best reduction potential was determined about -0.2V and the best time for synthesizing nanowires was 7 minutes. Chronoampermetric diagrams showed four steps, capacitive current, growth in the holes, reaching to the surface of PCT and the growth... 

    Time dependence of the surface plasmon resonance of copper nanorods

    , Article Journal of Physics Condensed Matter ; Volume 19, Issue 44 , 2007 ; 09538984 (ISSN) Azarian, A ; Iraji zad, A ; Dolati, A ; Ghorbani, M ; Sharif University of Technology
    2007
    Abstract
    Copper nanorods have been synthesized by electrodeposition with different lengths in porous polycarbonate (PCT) membranes with a pore diameter of 50nm and a thickness of 4νm. The PCT membranes were dissolved in dichloromethane (CH2Cl2) and the solvent was replaced by methanol solutions. Extinction peaks at 587, 581 and 574nm were observed for the Cu nanorods with aspect ratio R = 6,8 and 10 in methanol, respectively. Polarization of the molecules of the medium around the wires changes the dielectric constant of the medium. Hence, the wavelength of the extinction peaks does not shows good agreement with calculations that were done on basis of Gans' theory with nominal dielectric constant of... 

    Mechanical Behavior of Recycled Polyethylene Terephthalate/Polycarbonate/Glass Fiber Composites

    , M.Sc. Thesis Sharif University of Technology Haji Rezaei, Mohammad Javad (Author) ; Bagheri, Reza (Supervisor)
    Abstract
    Nowadays, with the increasing number of polyethylene terephthalate wastes, the issue of its recycling has become very important. Among the problems of polyethylene terephthalate recycling are its loss of crystallinity and mechanical properties. Recycled polyethylene terephthalate does not have the properties of new polyethylene terephthalate and using its mixture with other materials is an effective way to remove its waste from nature and return it to the production cycle. The aim of this study is to produce a mixture of recycled polyethylene terephthalate with polycarbonate and glass fibers with mechanical properties such as good impact strength, which ultimately leads to the production of... 

    Electrodeposition of well-defined gold nanowires with uniform ends for developing 3D nanoelectrode ensembles with enhanced sensitivity

    , Article Materials Chemistry and Physics ; Volume 213 , 2018 , Pages 67-75 ; 02540584 (ISSN) Bahari Mollamahale, Y ; Ghorbani, M ; Dolati, A ; Hosseini, D ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    Fabrication of well-defined gold nanowires (GNWs) is of significant importance in many fields such as sensing applications. In this study, the electrodeposition of well-defined GNWs inside polycarbonate (PC) template has been discussed in detail. GNWs were potentiostatically electrodeposited at different filling rates. The growth of GNWs at different stages of pore filling was monitored by electrochemical measurements and field-emission scanning electron microscopy (FE-SEM). It was confirmed that under growth rates between 2.5 and 4 nm/s, GNWs with smooth ends grew uniformly inside the template without any imperfections or corrugations. The length of GNWs was electrochemically controlled to... 

    Synthesis and Optical Properties of Cadmium Selenide Thin Films and Nanowires

    , M.Sc. Thesis Sharif University of Technology Kalhori, Hossein (Author) ; Iraji Zad, Azam (Supervisor) ; Dolati, Abolghasem (Supervisor)
    Abstract
    The interesting properties of metallic and semiconductor nanowires provide many applications in electronic and optoelectronic devices. In this project, we have synthesized Cu and CdSe nanowires using electrodeposition method. To adjust deposition bath conditions and characterize the structure of deposit first we prepared CdSe thin film on ITO substrates. The used solution was contained 0.1 M CdSO4+ 0.1 mM SeO2 in the acidic situation with pH=2.5. The best reduction potential was determined about -0.5 V. The XPS and XRD analyses showed that the ratio of cadmium to selenium in the films was 1:1 and the film’s structure is amorphous. Optical band gap of the cadmium selenide films was obtained... 

    Processing and Characterization of Microstructure and Mechanical Properties of PC/PBT Blend

    , M.Sc. Thesis Sharif University of Technology Shabani, Farzan (Author) ; Bagheri, Reza (Supervisor)
    Abstract
    Blend of Polycarbonate/ poly(butylene terephthalate) is among the most famous blends of polycarbonate/polyester with vast engineering applications and unique properties. Miscibility and compatibilization of this blend are important as they directly influence the general properties.Transesterification which occurs in the melt state, is a series of cutting and rejoining of dissimilar polymer chains. The reaction ruins the order of pure chains and forms block copolymers of different natures. Further progress in transesterification lead into a completely random copolymer of initial chains. Time, temperature and addition of catalyst can effectively influence transesterification.In this study,... 

    GMR in multilayered nanowires electrodeposited in track-etched polyester and polycarbonate membranes

    , Article Journal of Magnetism and Magnetic Materials ; Volume 308, Issue 1 , 2007 , Pages 35-39 ; 03048853 (ISSN) Nasirpouri, F ; Southern, P ; Ghorbani, M ; Iraji zad, A ; Schwarzacher, W ; Sharif University of Technology
    2007
    Abstract
    Commercially available track-etched polyester membranes were used as templates to electrodeposit Co-Ni-Cu/Cu multilayered nanowires, giving room-temperature current perpendicular to plane (CPP) giant magnetoresistance (GMR) values of up to ∼12%. In contrast to similar nanowires electrodeposited in track-etched polycarbonate membranes, the GMR obtained in multilayered nanowires electrodeposited in the polyester membranes increased with decreasing Cu-layer thickness tCu, for tCu in the 2-7 nm range, indicating a lack of ferromagnetic coupling through pinholes, etc. Transmission electron micrographs showed clear evidence for smooth, parallel layer interfaces in the nanowires. © 2006 Elsevier... 

    Electrodeposition of long gold nanotubes in polycarbonate templates as highly sensitive 3D nanoelectrode ensembles

    , Article Electrochimica Acta ; Volume 75 , 2012 , Pages 157-163 ; 00134686 (ISSN) Bahari Mollamahalle, Y ; Ghorbani, M ; Dolati, A ; Sharif University of Technology
    Elsevier  2012
    Abstract
    Electrodeposition of long and well-defined gold nanotubes in polycarbonate (PC) templates is still a major concern due to pore blockage problems. In the present study, we introduce a novel method for electrodeposition of long gold nanotubes within the pores of PC templates for the first time. In order to deposit gold atoms onto the pore walls preferentially, pore walls were functionalized with a coupling agent. Short and thin Ni nanotubes were then electrodeposited at the bottom of the pores. Gold nanotubes were subsequently electrodeposited at constant potentials and low solution concentrations. The morphology of nanotubes was characterized by electron microscopy and their formation... 

    Preparation and Surface Modification of PC Membranes for Gas Separation

    , M.Sc. Thesis Sharif University of Technology Sedghi, Saeed (Author) ; Soltanieh, Mohammad (Supervisor) ; Goodarznia, Iraj (Supervisor)
    Abstract
    The gas separation properties of polycarbonate (PC) membranes were investigated in this study. These membranes were prepared via dry and dry-wet phase inversion technique. Pure O2, N2, and CO2 gases were permeated through prepared membranes. The effects of membrane preparation conditions, including solvent type, non-solvent type, non-solvent/solvent volumetric ratio, polymer weight fraction, and drying temperature on the gas separation properties of dry PC membranes were investigated using Taguchi experimental design. Taguchi analysis show that polymer weight fraction offers the most important effect on the separation characteristics of the dry PC membranes. To get the highest... 

    Preparation of Polycarbonate Membrane for Industrial Wastewater Treatment in Membrane Bioreator

    , M.Sc. Thesis Sharif University of Technology Nazemi Dashtarjandi, Saeed (Author) ; Mousavi, Abbas (Supervisor) ; Bastani, Dariush (Supervisor)
    Abstract
    Today, membrane bioreactors (MBRs) process is one of the most important options in industrial and municipal wastewater treatment. In MBRs, membrane has an essential influence on their performance. In this study, polycarbonate was exploited as membrane to evaluate its performance in MBR since it has excellent mechanical properties. However, polycarbonate is brittle and breaks at low elongation at room temperature. Solution blending was utilized to improve polycarbonate’s properties. Blending membrane was characterized and assessed by scanning electron microscopy (SEM) and tensile strength. Polycarbonate solution blending with polyurehatne which has excellent toughness and flexibility enhance... 

    Processing and Characterization of Fracture Behavior of Hybrid Epoxy Nanocomposite Modified with Polycarbonate

    , M.Sc. Thesis Sharif University of Technology Amini NajafAbadi, Leila (Author) ; Bagheri, Reza (Supervisor)
    Abstract
    Epoxy resins have good mechanical and thermal properties, high chemical resistance and low shrinkage during cure but in spite of these good properties,they are brittle and this limits the usage of them. Adding a second, soft or rigid, phase has been always an effective strategy to improve the toughness of epoxy. Rigid phase used in resins are divided into organic and inorganic. The aim of this study is to increase epoxy toughness, maintaining mechanical properties and study effect of silica and polycarbonate on fracture toughness simultaneously. Mechanical properties including yield strength and elastic modulus are evaluated by pressure test. Additionally fracture toughness and three... 

    Study on Structure, Mechanical Properties, and Flammability of PC/ABS

    , M.Sc. Thesis Sharif University of Technology Alaei, Yasaman (Author) ; Bagheri, Reza (Supervisor) ; Seyed Reyhani, Morteza (Supervisor)
    Abstract
    Polycarbonate (PC) is known as one of the engineering plastics with remarkable mechanical properties, but the application of this polymer is limited due to its high notch sensitivity. Blending polycarbonate with other polymers such as acrylonitrile butadiene styrene (ABS) is a method to resolve this disadvantage. PC/ABS blends are commonly used in automotive industry, electrical and electronic devices. As PC and ABS are not completely miscible, a variety of compatibilizers are used to achieve a suitable microstructure and high engineering properties. Considering crucial applications of PC/ABS blends, different flame retardants are also used to reduce the flammability. These flame retardants... 

    The potentiostatic electrodeposition of gold nanowire/nanotube in HAuCl4 solutions based on the model of recessed cylindrical ultramicroelectrode array

    , Article Journal of the Electrochemical Society ; Volume 160, Issue 6 , 2013 , Pages D279-D288 ; 00134651 (ISSN) Bagheri Hariri, M ; Dolati, A ; Siavash Moakhar, R ; Sharif University of Technology
    2013
    Abstract
    The mechanism of gold nanowire (AuNW) and nanotube (AuNT) electrodeposition in a cyanide-free solution is investigated for the first time based on the analytical model of Szabo et al. (A. Szabo et al., J. Electroanal. Chem. 217 (1987) 417) for recessed cylindrical ultramicroelectrode (UME). Track-etched Polycarbonate Template (PCT) is served as cylindrical UME ensemble/arrays. Firstly, Au is nucleated through a charge transfer step and when the Nernst thickness exceeds the pore length, the radial diffusion is established around pore mouths. By overlapping of these domains, the planar diffusion toward the whole PCT surface is obtained. An analytic expression for global diffusion coefficient... 

    Electrodeposition of platinum nanowires: Electrochemical characterization

    , Article ECS Transactions, 25 April 2010 through 30 April 2010 ; Volume 28, Issue 18 , April , 2010 , Pages 25-35 ; 19385862 (ISSN) ; 9781607681946 (ISBN) Mahshid, S. S ; Dolati, A ; Hashemi Daryan, S ; Ghorbani, M ; Ghahramaninezhad, A ; Physical and Analytical Electrochemistry ; Sharif University of Technology
    2010
    Abstract
    Platinum nanowires (PtNWs) were electrodeposited on the polycarbonate templates (PCTs) in aqueous solution of H2PtCl6 in triply distilled water. Nanowires with diameters of 50 and 100 nanometers were electrodeposited on the same condition. The kinetics of electrodeposition process was studied by electrochemical techniques such as voltammetry and chronoamperometry methods. Increasing the scan rate, the peaks shifted to more negative potentials and the current density also increased in each peak which was typical for a diffusion-control process. The potential range for the deposition of platinum nanowires was specified and consequently the potentiostatic i-t transients were utilized to produce... 

    Efficient batch-mode mixing and flow patterns in a microfluidic centrifugal platform: a numerical and experimental study

    , Article Microsystem Technologies ; 2016 , Pages 1-13 ; 09467076 (ISSN) Mortazavi, S. M. A ; Tirandazi, P ; Normandie, M ; Saidi, M. S ; Sharif University of Technology
    Springer Verlag 
    Abstract
    During recent years centrifugal-based microfluidic devices known as Lab-on-a-CD have attracted a lot of attentions. Applications of these CD-based platforms are ubiquitous in numerous biological analyses and chemical syntheses. Mixing of different species in microscale is one of the essential operations in biochemical applications where this seemingly simple task remains a major obstruction. Application of centrifugal force, however, may significantly improve the flow agitation and mixing, especially when it is combined with the Coriolis force which acts perpendicular to centrifugal force. In this study, mixing process in minichambers located on a rotating platform under a periodic... 

    Efficient batch-mode mixing and flow patterns in a microfluidic centrifugal platform: a numerical and experimental study

    , Article Microsystem Technologies ; Volume 23, Issue 7 , 2017 , Pages 2767-2779 ; 09467076 (ISSN) Mortazavi, S. M. A ; Tirandazi, P ; Normandie, M ; Saidi, M. S ; Sharif University of Technology
    Abstract
    During recent years centrifugal-based microfluidic devices known as Lab-on-a-CD have attracted a lot of attentions. Applications of these CD-based platforms are ubiquitous in numerous biological analyses and chemical syntheses. Mixing of different species in microscale is one of the essential operations in biochemical applications where this seemingly simple task remains a major obstruction. Application of centrifugal force, however, may significantly improve the flow agitation and mixing, especially when it is combined with the Coriolis force which acts perpendicular to centrifugal force. In this study, mixing process in minichambers located on a rotating platform under a periodic... 

    An ultrasensitive label free human papilloma virus DNA biosensor using gold nanotubes based on nanoporous polycarbonate in electrical alignment

    , Article Analytica Chimica Acta ; 2018 ; 00032670 (ISSN) Shariati, M ; Ghorbani, M ; Sasanpour, P ; Karimizefreh, A ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    An impedimetric human papilloma virus (HPV) DNA biosensor based on gold nanotubes (AuNTs) in label free detection was materialized. The AuNTs decorated nanoporous polycarbonate (AuNTs-PC) template as biosensor electrode was fabricated by electrodeposition method. The single strand DNA (ss-DNA) probe was covalently immobilized onto the AuNTs-PC electrode. The hybridization of target sequences with the ss-DNA probe was observed by the electrochemical impedance spectroscopy (EIS). The biosensor showed high selectivity and could differentiate between the complementary, mismatch and non-complementary DNA sequences. The EIS measurements were matched to Randle's equivalent circuit. The...