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    Nanocellulose/Carbon Nanoparticles Nanocomposite Film Modified Electrode for Durable and Sensitive Electrochemical Determination of Metoclopramide

    , Article Electroanalysis ; Volume 27, Issue 11 , November , 2015 , Pages 2637-2644 ; 10400397 (ISSN) Shahrokhian, S ; Naderi, L ; Ghalkhani, M ; Sharif University of Technology
    Wiley-VCH Verlag  2015
    Abstract
    A novel electrochemical sensor based on nanocellulose-carbon nanoparticles (NC-CNPs) nanocomposite film modified glassy carbon electrode (GCE) is developed for the analysis of metoclopramide (MCP). Atomic force microscopy, scanning electron microscopy and electrochemical impedance spectroscopy were used to characterize the roughness, surface morphology and performance of the deposited modifier film on GCE. SEM image demonstrated that modifier nanoparticles are uniformly deposited on GCE, with an average size of less than 50nm. The electrochemical behavior of MCP and its oxidation product is studied using linear sweep and cyclic voltammetry over a wide pH range on NC-CNPs modified glassy... 

    Sensitive electrochemical sensor for determination of methyldopa based on polypyrrole/carbon nanoparticle composite thin film made by in situ electropolymerization

    , Article Electroanalysis ; Volume 23, Issue 9 , 2011 , Pages 2248-2254 ; 10400397 (ISSN) Shahrokhian, S ; Saberi, R. S ; Kamalzadeh, Z ; Sharif University of Technology
    2011
    Abstract
    A composite surface coating is prepared by electropolymerization of a mixture of pyrrole and carbon nanoparticles onto a glassy carbon electrode (GCE). The microscopic structure and morphology of the composite film is characterized by scanning electron microscopy. The modified electrode offers a considerable improvement in voltammetric sensitivity toward methyldopa (m-dopa), compared to the bare and polypyrrole-coated GCEs. A significantly enhanced anodic peak current together with a remarkable increase in sharpness of the cyclic voltammetric (CV) signals are observed for the detection of m-dopa. The effect of experimental parameters, such as scan rate and pH, are investigated by monitoring... 

    Electrodeposition of Copper Oxide Nanoparticles on Precasted Carbon Nanoparticles Film for Electrochemical Investigation of anti-HIV Drug Nevirapine

    , Article Electroanalysis ; Volume 27, Issue 8 , June , 2015 , Pages 1989-1997 ; 10400397 (ISSN) Shahrokhian, S ; Kohansal, R ; Ghalkhani, M ; Amini, M. K ; Sharif University of Technology
    Wiley-VCH Verlag  2015
    Abstract
    This work describes the development of a novel electrochemical sensor based on electrodeposition of copper oxide nanoparticles onto carbon nanoparticle (CNP) film modified electrode for the analysis of the anti-HIV drug, nevirapine (NEV). The electrochemical experiments were performed using linear sweep and cyclic voltammetry. Atomic force microscopy was applied for surface characterization of the deposited modifier film (CuO-CNP) on glassy carbon electrode (GCE). No oxidation peak was observed for NEV on the bare GCE, but both CNP-GCE and CuO-CNP-GCE showed a distinctive anodic response towards NEV with considerable enhancement (276-fold and 350-fold, respectively) compared to CuO-GCE. The... 

    Electrochemical determination of piroxicam on the surface of pyrolytic graphite electrode modified with a film of carbon nanoparticle-chitosan

    , Article Microchimica Acta ; Volume 170, Issue 1 , August , 2010 , Pages 141-146 ; 00263672 (ISSN) Shahrokhian, S ; Jokar, E ; Ghalkhani, M ; Sharif University of Technology
    2010
    Abstract
    The electrochemical behavior of the anti-inflammatory drug piroxicam is studied at the surface of a plain pyrolytic graphite electrode modified with chitosan-doped carbon nanoparticles. An electroactive surface was produced by drop-casting a suspension of the modifier and characterized by atomic force microscopy. A remarkable enhancement is found in studies on the cyclic voltammetric response towards piroxicam. This is described on the basis of the thin-layer mass transport regimes within the porous films, which leads to a considerable increase in the active surface area of the electrode. The electrode shows a linear response to piroxicam in the range of 0.05-50 μM, with a detection limit of... 

    Biomimetic sensor for dobutamine employing Nano- TiO2/Nafion/carbon nanoparticles modified electrode

    , Article Electroanalysis ; Volume 28, Issue 5 , 2016 , Pages 970-978 ; 10400397 (ISSN) Shahrokhian, S ; Ghalkhani, M ; Kohansal, R ; Mohammadi, R ; Sharif University of Technology
    Wiley-VCH Verlag  2016
    Abstract
    A novel voltammetric biosensor based on nano-TiO2/nafion/carbon nanoparticles modified glassy carbon electrode (TiO2/N/CNP/GCE) was developed for the determination of dobutamine (DBA). Characterization of the surface morphology and property of TiO2/N/CNP layer was carried out by the scanning electron microscopy and atomic force microscopy. The electrochemical performance of the modified electrode was investigated by means of the cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy techniques. Effective experimental variables, such as the scan rate, pH of the supporting electrolyte, drop size of the casted modifier suspension and accumulation... 

    Controlling Amyloid Formation Using Novel Carbon Based Nanoparticles

    , M.Sc. Thesis Sharif University of Technology Yahyazadeh, Amin (Author) ; Kalhor, Hamid Reza (Supervisor)
    Abstract
    Proteins carry out most important roles in the organisms and they have a number of functions including structural, catalytically, regulatory and transportal, However for protein to have functional role they must be able to possess tridimensional structure. Several proteins due to various genetic and physico-chemical conditions have shown to alter their tridimensional structure leading to insoluble fibrilar structure. One of the properties of these insoluble fibrils is conformational change, converting to β-sheet rich structures; the entire process of converting soluble to proteins insoluble fibrils known as amyloid formation. The proteins amyloidosis have been seen as causative role in a... 

    Extending a Hybrid Finite-volume-element Method for Numerical Analysis of Reacting Flows and the Study of Soot Nanoparticles Formation and Growth

    , Ph.D. Dissertation Sharif University of Technology Ghafourizadeh, Majid (Author) ; Darbandi, Masoud (Supervisor)
    Abstract
    There are some parameters, which can affect the performance of a combustor less and more, e.g., fuel-oxidant mixing process, turbulence generation, combustion process, and so on. A stoichiometric reaction as a unique reaction, in which all the reactants are consumed to form the stable products, can be categorized as the most economic reaction. The majority of industrial combustion apparatus consumes hydrocarbon fuels and departs from ideal combustion conditions, which expects products like CO2 and H2O. Combustion by-products reduce the combustion efficiency and cause environmental damages and human health problems. To resolve the human health problems and environmental hazardous issues, the... 

    Preparation and Investigation of the Electrochemical of the Glassy Carbon Electrode Modified by Nanocellulose/Carbon Nanoparticle: Application to Pharmaceutical Determinations

    , M.Sc. Thesis Sharif University of Technology Balotf, Hamed (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In the first part, a novel electrochemical sensor for clonazepam (CLNP) was fabricated based on immobilizing cellulose nanofibers /carbon nanoparticles (CNFs/CNPs) nanocomposite on glassy carbon electrode (CNFs/CNPs/GCE). The combination of CNFs and CNPs produced a novel kind of structurally uniform and electro-analytically active nanocomposite. The surface morphology of CNFs/CNPs layer deposited onto glassy carbon electrode was characterized by scanning electron microscopy. The results of the voltammetric investigations showed a considerable enhancement in the cathodic peak current of CLNP (up to 60 times) on the surface of CNFs/CNPs/GCE relative to the bare GCE. Under the optimal... 

    Electrochemical Sensors Based on Electrodes Modified with Composites of Carbon Nanostructures and Polypyrrole; Application to Electrochemical Investigations and Determination of Nifedipine and Tizanidine

    , M.Sc. Thesis Sharif University of Technology Shamloofard, Maryam (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In the first part, the electropolymerization of pyrrole was performed in the presence of Titan Yellow (TY) as a dopant anion on the surface of the electrode precoated with CNTs. The modified electrode was used to study the voltammetric response of tizanidine (TIZ). A remarkable increase was observed in the anodic peak current of TIZ on the surface of the modified electrode relative to the bare GCE. The surface morphology PPY/CNT/GCE was thoroughly characterized by scanning electron microscopy (SEM) and cyclic voltammetry (CV) techniques. Under the optimized analysis conditions, the modified electrode showed two linear dynamic ranges of 0.01 - 1 μM and 1-10 μM with a detection limit of 3 nM... 

    Synthesis of S- and N-doped Carbon Quantum Dots

    , M.Sc. Thesis Sharif University of Technology Minagar, Ava (Author) ; Madah Hosseini, Hamid Reza (Supervisor)
    Abstract
    In recent years, adjustable optical properties, simple and inexpensive synthesis, and excellent biocompatibility of carbon dots have attracted much attention. However, the widespread use of carbon dots in biomedical diagnostics, photoluminescence, and photocatalysis has been limited due to a lack of emission or excitation in the red or near-infrared region. Studies have shown that doping in carbon dots can affect the displacement and increase the light intensity. This study aims to use the engineering methods of optical properties of carbon points by doping heteroatoms and adjusting the surface state to synthesize biocompatible carbon dots with luminescence at long wavelengths with strong... 

    Investigating Process Factors on Red-shift of Photoluminescence of Carbon Dots

    , M.Sc. Thesis Sharif University of Technology Feghhi, Fazeleh (Author) ; Madah Hosseini, Hamid Reza (Supervisor)
    Abstract
    In recent years, studies in luminescent carbon dots are overgrowing, the prominent features of carbon quantum dots include cheap and straightforward synthesis, excellent biocompatibility, and adjustable optical properties. However, the widespread use of carbon dots in biomedical diagnostics, photoluminescence, and photocatalysis has been limited due to a lack of emission and excitation in the red or near-infrared region.. However, the widespread use of carbon dots in biomedical diagnostics, photoluminescence, and photocatalysis has been limited due to a lack of emission and excitation in the red or near-infrared region. This research tried to produce carbon dots with redshift in emission... 

    Improvement of Polymer Composites Thermal Conductivity by Nanoparticles

    , M.Sc. Thesis Sharif University of Technology Kazemi Ranjbar, Sina (Author) ; Nouri Broujerdi, Ali (Supervisor)
    Abstract
    The new generation of electronic devices including 5G internet, wearable electronics, LED optoelectronics or cloud computing devices have higher power density as their computing power increases and their sizes reduce. The increase in power density leads to higher heat generation and consequently higher operating temperature which reduces their lifetime and reliability. In recent years development of novel solutions for electronic cooling has been persued. Thermal interface material that inserted between heat source and heat sink is the main component in electronic cooling. These materials consists of a polymeric base that filled with highly thermally conductive solid particles. By emergence... 

    Investigation of Mechanical and Rheological Properties of Recycled PP – Calciumcarbonat Nanocomposites

    , M.Sc. Thesis Sharif University of Technology Janzadeh, Amir Hossin (Author) ; Moosavi, Abass (Supervisor) ; Frounchi, Masood (Supervisor)
    Abstract
    In this work the effect of recycling process and nanometric CaCO3 on the rheological and heat-sealing properties of co-polymer Polypropylene (R40) was studied. Nanocomposites with recycled and neat matrix were prepared with twin extruder. Complex viscosity, dynamic modulus, flexural and tensile properties, impact strength and sealing ability of nanocomposites of neat Co-PP (R40) and Recycled Co-PP (RPP) determined according to the relevant standard specifications.Rheological analysis revealed that incorporation of nanofiller enhances values of Complex viscosity and dynamic modulus, broadening molecular weight distribution (MWD) and decrease cross over point (ωc, GC) for RPP. In this study,... 

    Preparation and Application of the Glassy Carbon Electrodes Modified with Carbon Nanomaterials for Studies of the Electrochemical Behavior and Quantitative Determination of Metoclopramide and Furazolidone

    , M.Sc. Thesis Sharif University of Technology Naderi, Leila (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In the first part, a novel electrochemical sensor based on nanocellulose-carbon nanoparticles (NC–CNPs) nanocomposite film modified glassy carbon electrode (GCE) is developed for the analysis of metoclopramide (MCP). The electrochemical behavior of MCP was investigated on the surface of the modified electrode using cyclic voltammetry (CV). Characterization of the surface morphology and properties of NC/CNPs was carried out by scanning electron microscopy (SEM), atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS). Effective experimental variables, such as scan rate, pH of the supporting electrolyte, drop size of the casted modifier suspension and accumulation... 

    Electrochemical Determination of Piroxicam at thin Carbon
    Nanoparticle Composite And Investigation of the Electrochemical Behavior and Synthesis of Catechols in the Presence of Mercapto Methyl Tetrazol as a Nucleophile

    , M.Sc. Thesis Sharif University of Technology Jokar, Effat (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    The electrochemical oxidation behavior of the anti-inflammatory drug piroxicam was investigated. A carbon nanoparticle (CNP)-chitosan (CS) film-coated graphite electrode (PGE) was fabricated and the electrochemical behaviors of piroxicam on its surface was investigated by the means of cyclic voltammetry (CV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). In comparison to the bare PGE, at the surface of the CNP-CS film modified electrode, the oxidation peak current of piroxicam increased significantly and the peak potential shifted negatively. Consequently, a simple and sensitive electroanalytical method was developed for the determination of piroxicam. The... 

    Reactive Crystallization of Calcium Carbonate Nanoparticles in Impinging Jets Reactors

    , M.Sc. Thesis Sharif University of Technology Habibi, Amir Hossein (Author) ; Molaei, Asghar (Supervisor)
    Abstract
    Due to their highly efficient micromixing rates, confined impinging jet reactors can be beneficial in treating mixing-sensitive processes such as precipitations or crystallizations at high supersaturation. Successful scale-up of these reactors requires a decent insight of geometric design and operating conditions of these systems. This paper deals with the reactive crystallization of calcium carbonate nano-particles in two-impinging jets reactors. The influence of jet velocity (Jet Re number), nozzle diameter, and chamber ratio on the PSD and mean particle size of the product are investigated. In addition, the effect of supersaturation ratio, ion ratio and quenching ratio on the nucleation,... 

    Nano composite coating based on cellulose nanofibers/carbon nanoparticles: application to voltammetric determination of clonazepam

    , Article Journal of Solid State Electrochemistry ; Vol. 19, issue. 1 , 2014 , p. 251-260 Shahrokhian, S ; Balotf, H ; Ghalkhani, M ; Sharif University of Technology
    Abstract
    A novel electrochemical sensor for clonazepam (CLNP) was fabricated based on immobilizing cellulose nanofibers/carbon nanoparticles (CNFs/CNPs) nanocomposite on glassy carbon electrode (CNFs/CNPs/GCE). The combination of CNFs and CNPs produced a novel kind of structurally uniform and electro-analytically active nanocomposite. The surface morphology of CNFs/CNPs layer deposited onto glassy carbon electrode was characterized by scanning electron microscopy. The results of the voltammetric investigations showed a considerable enhancement in the cathodic peak current of CLNP (up to 60 times) on the surface of CNFs/CNPs/GCE relative to the bare GCE. Under the optimal conditions, the modified... 

    Application of glassy carbon electrode modified with a carbon nanoparticle/melamine thin film for voltammetric determination of raloxifene

    , Article Journal of Electroanalytical Chemistry ; Volume 780 , 2016 , Pages 126-133 ; 15726657 (ISSN) Shahrokhian, S ; Ghalkhani, M ; Balotf, H ; Salimian, R ; Sharif University of Technology
    Elsevier B.V  2016
    Abstract
    As a selective estrogen receptor modulator, raloxifene (RXF) prevent of osteoporosis in postmenopausal women by estrogenic actions on bone and decreases the risk of invasive breast cancer by anti-estrogenic actions on the breast and uterus tissue. However, RXF may increase the risk of blood clots, including deep vein thrombosis and pulmonary embolism. For the first time glassy carbon electrode modified with a thin film of melamine/carbon nanoparticles (CNPs/Mela) was constructed and used for the sensitive voltammetric determination of RXF. In comparison with unmodified electrode, the presence of the CNPs/Mela film resulted in a remarkable increase in the peak currents and sharpness of the... 

    Electrochemical sensing based on carbon nanoparticles: A review

    , Article Sensors and Actuators, B: Chemical ; Volume 293 , 2019 , Pages 183-209 ; 09254005 (ISSN) Asadian, E ; Ghalkhani, M ; Shahrokhian, S ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    The emergence of nanoscience and nanotechnology has opened up new horizons to researchers. In this regard, carbon nanomaterials are considered as the cornerstone of numerous investigations. Among various carbon nanostructures, “Carbon nanoparticles (CNPs)” have attracted a great deal of attention during the past few years due to their unique properties such as high surface area, non-toxicity, biocompatibility as well as simple and low-cost synthetic procedures via environmentally friendly routes. Thanks to these properties along with their interesting optical behavior, CNPs have found diverse applications in the fields of bioimaging, nanomedicine, photo/electro-catalysis, and bio/chemical... 

    Preparation and Study of the Electrochemical Ptal Oxide Particles/Carbon Nanoparticles: Application to Pharmaceutical Determinations

    , M.Sc. Thesis Sharif University of Technology Kohansal, Razieh (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In the first work, a novel voltammetric biosensor basedon TiO2-nafion-carbon nanoparticles modified glassy carbon electrode (TiO2/N/CNP/GCE) was developed for the determination of DBA. The electrochemical performance of the modified electrode was investigated by means of cyclic voltammetry (CV), different pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) techniques. Characterization of the surface morphology and properties of TiO2/N/CNP was carried out by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Effective experimental variables, such as scan rate, pH of the supporting electrolyte, drop size of the cast modifier suspension and accumulation...