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    Preparation and Investigation of the Electrochemical behavior of the Glassy Carbon Electrode Modified with Nanodiamond/Nanographite and NanoNi Composites: Applications to Pharmaceutical Determinations

    , M.Sc. Thesis Sharif University of Technology Koolivand, Zeinab (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    Part 1: In the first work, the electrochemical behavior of Ceftriaxone was thoroughly investigated at the surface of a glassy carbon electrode modified with nano-diamond graphite (NDG). The surface morphology and electrochemical properties of thin film modifier are characterized by Scanning electron microscopy (SEM) and cyclic voltammetry (CV) techniques. The prepared electrode showed a considerable improvement in the peak current of Ceftriaxone compared to either glassy carbon electrode or nanodiamond (NDs) modified glassy carbon electrode. Under the optimum conditions, the modified electrode showed a wide linear dynamic range of 0.04-10 μM with the detection limit of 10 nM for voltammetric... 

    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... 

    Development and Application of Carbon Nanomaterials-based Polymer Modified Electrodes for Electrochemical Determination of Pharmaceutical Compounds

    , Ph.D. Dissertation Sharif University of Technology Kamalzadeh, Zahra (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In this thesis, in the first part, a promising electrochemical sensor was developed based on a layer by layer process by electropolymerization of pyrrole in the presence of new coccine (NC) as dopant anion on the surface of the CNTs pre-coated glassy carbon electrode (GCE). The modified electrode was used as a new and sensitive electrochemical sensor for voltammetric determination of sumatriptan (SUM). The results showed a remarkable increase in the anodic peak current of SUM in comparison to the bare GCE. In the second part, the electropolymerization of pyrrole was performed in the presence of Nitrazine Yellow (NY) as a dopant anion on the surface of the electrode precoated with CNTs. The... 

    Design and Fabrication Nanocomposite Modified Electrode Materials Based on Transition Metal Phosphide Using Copper Hydroxide Nanotubes as a Catalytic Substrate for Glucose Sensing in Non-Enzymatic Sensors

    , M.Sc. Thesis Sharif University of Technology Kazemi Abatari, Zeynab (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In this study, transition metal phosphide, with a high accessible surface and abundant electroactive centers, was used as an electrocatalyst to fabrication an electrochemical sensor of Gloucose. The direct growth of thin film of nanocomposite can be considered as an efficient method to modify the electrode surface, and the application of these modified electrodes as electrochemical sensors. nanocomposite of transition metal phosphide (CuCoP) were directly grown on Cu(OH)2 nanotubes (as-prepared on GCE) in order to design hierarchical core-shell nanostructure with using efficient, inexpensive and fast method. Here, Cu(OH)2 nanotubes not only served as substrate, but also steer the CuCoP to... 

    Chemical Modification of Glassy Carbon Electrode by Carbon Nanostructures/Conductive Polymers Composites and Its Application in The Study of Electrochemical Behaviour and Determination of Salbutamol and Isoprenaline

    , M.Sc. Thesis Sharif University of Technology Panahi, Saba (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In the first part of thesis, the electropolymerization of pyrrole was performed in the presence of new coccine (NC) as a dopant anion on the surface of the electrode precoated with SWCNT. The modified electrode was used to study the voltammetric response of salbutamol (SAL). The results showed a remarkable increase in the anodic peak current of SAL in comparison 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 0.02 – 0.1 μM and 0.1-10 μM with a detection limit of 6 nM for the... 

    Preparation and Investigation of the Electrochemical Behavior of Sensors Modified with Reduced Graphene Oxide nanohybrids for Electrochemical Determinations of Some Biologically Important Compounds

    , M.Sc. Thesis Sharif University of Technology Navabi, Mostafa (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In the first work, a stable composite film of silver nanoparticles decorated on reduced graphene oxide is easily prepared. The surface morphology of the modified electrode is characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The electrochemical behavior of TNZ on the surface of the modified electrode is investigated by using linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). The prepared modified electrode acts as a highly sensitive platform for the voltammetric determination of tinidazole (TNZ). Voltammetric investigations demonstrated that, in comparison to the glassy carbon electrode individually coated with... 

    Design of a Microfluidic System for Continuous Glucose Measurement, as well as Fabricating and Experimentally Testing the Biosensor

    , M.Sc. Thesis Sharif University of Technology Najmi, Armita (Author) ; Saeedi, Mohammad Saeed (Supervisor) ; Kazemzadeh Hannani, Siamak (Supervisor) ; Shahrokhian, Saeed (Co-Supervisor)
    Abstract
    Diabetic patients, unlike other people whose blood glucose vary in a limited and normal range, encounter hyperglycemia and hypoglycemia, so their glucose level should be measured periodically and kept in the normal range. The aim of this research is to design an implantable integrated microfluidic system in order to regularly measure the glucose level in the human body, using the microdialysis method. The main compartments of this system are a micropump, array of hollow microneedles at the base of them located semipermeable membranes, the channels of dialysis fluid and an electrochemical sensor for measuring the glucose level. The micropump of this system is designed and simulated based on... 

    Morphology-Dependent Electrocatalytic Activity of Silver Nanostructures and Differentia Pulse Voltammetry Determination of Atorvastatin at Silver Nanowires Modified Electrode

    , M.Sc. Thesis Sharif University of Technology Naseri, Amene (Author) ; Shahrokhian, Saeed (Supervisor) ; Hormozi Nezhad, Mohammad Reza (Supervisor)
    Abstract
    In this work two shapes of silver nanostructures including silver nanowires and silver nanocubeswere synthesized by polyol method. Silver nanostructures were characterized by SEM, XRD and UV-Vis spectroscopy. Afterwards the morphology-dependent electrocatalyticperformance of these nanocrystals on the differential pulse behavior of naltrexone (NAL) was investigated. To this aim the differential pulse voltammetric behavior of NAL on a glassy carbon electrode modified with electrochemical deposited gold nanoparticles conjugated with different shapes of silver nanostructures and nafion was investigated. It was proved that silver nanowires show more effective electrocatalytic activity toward... 

    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... 

    Design and Fabrication of Flexible Fiber- Shaped Hybrid Micro- Supercapacitors Based on Carbon Nanostructures and Oxides, Sulfides and Phosphides of Some Transition Metals

    , Ph.D. Dissertation Sharif University of Technology Naderi, Leila (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    Miniaturization of electronic devices with portable, flexible and wearable characteristics created a great demand for high-performance microscale energy storage devices with lightweight and flexible properties. Among the energy storage devices, wire-shaped micro-supercapacitors have recently received tremendous attention due to their small size, lightweght, and high flexibility. In the first part, the porous dendritic Ni-Cu film was prepared on Cu wire substrate (CW) for fabrication of high- performance wire-type micro-supercapacitors (micro-SCs). The porous structure with dendritic morphology provides a high surface area, short ion diffusion pathway and low contact resistance between... 

    Preparation and Investigations of Flexible Supercapacitors Using Nanocomposites with Graphene-based Structures and Layered double hydroxide Ni/Co and Manganese Molybdate

    , Ph.D. Dissertation Sharif University of Technology Mehrabi Matin, Bahareh (Author) ; Shahrokhian, Saeed (Supervisor) ; Iraji-zad, Azam (Supervisor)
    Abstract
    In the first part of this research, for the first time, we introduced a flexible high performance graphene-based supercapacitor using silver fiber fabric as the current collector. The silver fiber fabric offers remarkable advantages such as light weight, mechanical flexibility and ease of integration with electronic textiles, which well-suited for wearable energy storage devices. A new hybrid material of graphene-silver fiber fabric (rGO/SFF) was prepared through a facile electrophoretic deposition of graphene and being used as a binder-free flexible supercapacitor electrode. In order to obtain the optimum condition, the effect of deposition time was investigated and a duration time of 10... 

    , M.Sc. Thesis Sharif University of Technology Mahdavi Shakib, Akbar (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract

    This experimental work is of two parts. First, self-assembled monolayers of cysteamine was formed on the gold electrode surface which leaded to the formation of amine groups on the surface; then amine bond was formed between these amine groups and the carboxylic acid groups of acid treated multi-walled carbon nanotubes (MWCNTs). The modified electrode was used for voltammetric determination of dopamine in the presence of uric acid. In the second part, acid treated MWCNTs were decorated with ruthenium nanoparticles; then the resulting composite was used for surface modification with the exact same procedure as the first part. Ruthenium nanoparticles on the electrode surface were... 

    Constructing and Investigation of the Electrochemical Behavior of Nanocomposite of Conducting Polymers on Copper Hydroxide Nanotubes; Application to Determination of Glucose

    , M.Sc. Thesis Sharif University of Technology Manafi, Reza (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    A novel amperometric non-enzymatic glucose (NEG) sensor is designed by a facile preparation method. It is made by electrodeposition of Cu clusters and converting them to Cu(OH)2 nanotubes (Cu(OH)2NTs) arrays along with thin-film electro-polymerized of spindle-shaped polypyrrole (PPy@Cu(OH)2NTs), which have been doped by using sodium Benzene-1,3- disulfonate as an anion dopant. The electrochemical performance of the modified electrode toward glucose detection is investigated by various electrochemical methods. Under the optimized conditions, a significant electrochemical response improvement is observed toward the electro-oxidation of glucose on the surface of PPy@Cu(OH)2NTs electrode... 

    Separation and Treatment of Cutting Oil Emulsions using Electrocoagulation

    , M.Sc. Thesis Sharif University of Technology Maleknia, Arash (Author) ; Shahrokhian, Saeed (Supervisor) ; Nazari Alavi, Alireza (Supervisor)
    Abstract
    Cutting oils are used for reducing friction, cooling and preventing from corrosion in the industry. These oils are mixed in different proportions with water and produce emulsion. In this study, treatment of oil-water emulsions is studied using electrocoagulation with aluminum, copper and stainless steel electrodes as a pretreatment stage. The efficiency of electrocoagulation process was obtained through the measurement of COD removal percentage and or the required time for the treatment. COD is the required oxygen for oxidizing oxidizable materials through oxidizing substances in the solution.In this study, the effect of operating parameters such as emulsion concentration (volume/volume... 

    Using of Oxides, Hydroxides and Sulfides of Some Transition Metals and Carbon Nanostructures in Supercapacitors

    , Ph.D. Dissertation Sharif University of Technology Mohammadi, Rahim (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    Electrochemical capacitors are type of electrical energy storage devices that research on them has grown due to the development of hybrid vehicles. It is proved that lectrodes configuration has vital role in electrochemical capacitors performance. In this thesis, transition metal hydroxides, oxides and sulfides along with carbonaceous materials have benn used as active materials in supercapacitors. In first section, graphite has been poroused by applying anodic potential of 2V in acidic electrolyte which results in exfoliation of graphite planes due to gas diffusion to the interlayer of graphite sheets. The prepared porous graphite was used as precursor for electrodeposition of nickel... 

    Investigating Electrochemical Behavior of Biosensor Based on Vertically Aligned Carbon Nanotubes

    , Ph.D. Dissertation Sharif University of Technology Gholizadeh, Azam (Author) ; Shahrokhian, Saeed (Supervisor) ; Iraji Zad, Azam (Co-Advisor) ; Mohajerzadeh, Shamsoddin (Co-Advisor) ; Vossoughi, Manoochehr (Co-Advisor)
    Abstract
    In this research we focus on fabrication, characterization and performance of biosensors based on vertically aligned carbon nanotubes. Carbon nanotubes have been used as high density carbon nanotubes and nanoelectrode array. Carbon nanotubes have been grown using plasma enhanced chemical vapor deposition method. Characterization and performance of biosensors have been studied by cyclic voltammetry and electrochemical impedance spectroscopy methods.
    The mediator-less glutamate biosensor is prepared based on covalently attached glutamate dehydrogenase on vertically aligned carbon nanotubes. The biosensor has a low detection limit of 57 nM, two linear range of 0.1-20 µM with sensitivity of... 

    Design and Fabrication of an Optimized Wake Equalizing Duct in Order to Improve Propulsion System Operation

    , M.Sc. Thesis Sharif University of Technology Ali Mirzazadeh, Siamak (Author) ; Seif, Mohammad S (Supervisor) ; Rad, Manouchehr ($item.subfieldsMap.e)
    Abstract
    Special geometrical sections, known as “duct”, which can be installed on merchant vessels stern in order to improve propulsion system and propeller performance, today have evolved considerably. The force which produces by the propeller depends on efficiency of propulsion system. In the way of improving the efficiency of propulsion systems, by using these special geometrical sections, to much research have been done from the mid-twentieth century. The Wake Equalizing Ducts (WEDs) in addition to conduct the more uniform fluid flow to the propeller disk (which causes to improve the propeller operation), affect on flow separation in ship stern zone and will decrease the separated flow zone.... 

    Preparation and Investigation of Electrochemical Sensors for Determination of Pharmaceutical and Biological Compunds Based on Glassy Carbon Electrode Modified with Polypyrrole/Carbon Nanotube Composite

    , M.Sc. Thesis Sharif University of Technology Azimzadeh Sani, Mahnaz (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In the recent years, conductive polymers are widely used in the design and construction of chemical and biological sensors.The polypyrrole due to features such as good thermal and chemical stability, ease of synthesis and better conductivity than other conductive polymers, atracts much attention. In order to modification of electrode surface,adhesiveand thin polymer films can be electropolymerized in the presence of organic or inorganic dopants on the surface of metal or carbon surfaces in aqueous or organic solutions. On the other hand carbon nanotubes by owing unique properties such as chemical stability and high electrical conductivity are good choice for electrod surface modification.... 

    Fabrication of Composite Electrode Materials Based on Bi-Metalic Metal-Organic Frameworks for Designation of Amperometric Non-Enzymatic Glucose Sensors

    , M.Sc. Thesis Sharif University of Technology Ataei Kachouei, Matin (Author) ; Shahrokhian, Saeed (Supervisor)
    Abstract
    In the present study, the method of direct growth was used to grew bi-metalic MOFs based on cobalt and zinc, as electroactive centers, for preparing electrochemical sensors for the determination of glucose. In comparison to most of the electrochemical sensing platforms based on MOFs for determining glucose, which suffer from some disadvantages like time-consuming synthesis procedures and using hazardous organic solvents, the proposed in-situ growth method is much faster and without any need to toxic organic solvents. Herein, cobalt and zinc-based MOFs were grown on the surface of glassy carbon electrode by the direct and rapid conversion of layered double hydroxide nanosheets intermediates.... 

    Fabrication of Applied Electrode Materials based on Metal-Organic Frameworks to Design Non-Enzymatic Electrochemical Sensing Platforms for Measuring of Glucose in Physiological Samples

    , M.Sc. Thesis Sharif University of Technology Ezzati, Milad (Author) ; Shahrokhian Dehkordi, Saeed (Supervisor)
    Abstract
    In the first work, the method of direct growth was used to grew MOFs based on cobalt, as electroactive centers, for preparing electrochemical sensors for the determination of glucose. In comparison to most of the electrochemical sensing platforms based on MOFs for determining glucose, which suffer from some disadvantages like time-consuming synthesis procedures and using hazardous organic solvents, the proposed in situ growth method is much faster and no need to toxic organic solvents. Herein, cobalt-based MOFs were grown on the surface of the reduced graphene oxide modified glassy carbon electrode by the direct and rapid conversion of cobalt hydroxide nanosheets intermediates. The...