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    Application of Cellulose Nanofibers Coated Quartz Crystal Microbalance (QCM)Biosensor for Amino Acid Detection in Aqueous Media

    , Ph.D. Dissertation Sharif University of Technology Hosseini, Marzieh Sadat (Author) ; Iraji Zad, Azam (Supervisor) ; Vossoughi, Manouchehr (Supervisor)
    Abstract
    Developing a simple, cost effective and accurate detection method for L-lysine (Lys), L-leucine (Leu) and glycine (Gly) as the important analytes in clinical diagnostics, biological processes and food industries is of great interest. Therefore, in the first part of this research, cellulose nanofibrils (CNFs) were coated on a quartz crystal microbalance (QCM) surface by spin coating to achieve a QCM biodetector for Gly. Thus, the two-layer CNFs coating was selected as sensing film and was applied for following experiments. In the next step, the coated QCMs were carefully characterized before and after interaction with Gly using water contact angle (WCA), Fourier transform infrared... 

    Application of Cellulose Nanofibers Coated Quartz Crystal Microbalance (QCM) Biosensor for Amino Acid Detection in Aqueous Media

    , Ph.D. Dissertation Sharif University of Technology Hosseini, Marzieh Sadat (Author) ; Irajizad, Azam (Supervisor) ; Vossoughi, Manouchehr (Supervisor)
    Abstract
    Developing a simple, cost effective and accurate detection method for L-lysine (Lys), L-leucine (Leu) and glycine (Gly) as the important analytes in clinical diagnostics, biological processes and food industries is of great interest. Therefore, in the first part of this research, cellulose nanofibrils (CNFs) were coated on a quartz crystal microbalance (QCM) surface by spin coating to achieve a QCM biodetector for Gly. Thus, the two-layer CNFs coating was selected as sensing film and was applied for following experiments. In the next step, the coated QCMs were carefully characterized before and after interaction with Gly using water contact angle (WCA), Fourier transform infrared... 

    Synthesis of Magnetic Nanocomposite Scaffolds by Electrospinning Method and Study of Drug Release Behavior

    , Ph.D. Dissertation Sharif University of Technology Khodaei, Azin (Author) ; Bagheri, Reza (Supervisor) ; Madaah Hosseini, Hamid Reza (Supervisor)
    Abstract
    Controlled release is a crucial factor in tissue engineering and cancer-therapy applications. The main purpose of current research is to synthesis smart magnetic nanocarriers for hydrophobic drug and embedding them in a fibrous platform for anti-cancer/ tissue engineering applications. In this regard, three different drug delivery systems of magnetic nanocolloid, magnetic fibers and hydrogels were studied. In the first phase, superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized and then were modified using oleic acid and thermo-sensitive polymer of pluronic F127/F68. After characterization of this composite, Response Surface Methodology (RSM) was applied to model the lower... 

    Synthesis of Titania Coated Upconversion Nanoparticles with the Capability of Being Utilized in Photodynamic Therapy Under the Near-Infrared Radiation

    , Ph.D. Dissertation Sharif University of Technology Ghorashi, Maryam Sadat (Author) ; Madaaah Hosseini, Hamid Reza (Supervisor) ; Soleimani, Masoud (Supervisor) ; Mohajerani, Ezeddin (Co-Supervisor)
    Abstract
    Development of novel photosensitizers and photocatalysts with near-infrared (NIR) light activity and efficient sunlight harvesting is of great importance in photodynamic therapy and environmental remediation. In this work, very small (20 nm) upconverter SrF2:Yb,Tm@CaF2:Yb@Fluorine-doped TiO2 heteronanoparticles (denoted as UCNPs@TiO2) with strong UV-blue emission and wide-spectrum photocatalytic activity were synthesized via a facile three-step hydrothermal method, for the first time. The SrF2: Yb,Tm upconverter nanoparticles were produced as the light-emitting core, epitaxially-grown CaF2 : Yb as the middle shell to enhance the Upconversion luminescence efficiency and TiO2 as the... 

    Fabrication and Characterization of Porous Carbon-Graphene Composite as an Absorbent for Industrial Pollutants

    , Ph.D. Dissertation Sharif University of Technology Alizadeh, Omid (Author) ; Madaah Hosseini, Hamid Reza (Supervisor) ; Pourjavadi, Ali (Supervisor) ; Bahramian, Ahmad Reza (Co-Supervisor)
    Abstract
    The amount of fresh water suitable for various uses is decreasing day by day. This may be due to evaporation or contamination of water or such. Heavy metal cations, dyes, oils and solvents are the most important substances that contaminate water. There are various ways to remove these contaminants, one of which is the absorption of these substances by suitable absorbents. Carbon compounds have attracted much attention among all the absorbents used so far. The aim of this study is to produce carbon aerogels from an economic and modify its structure and properties by adding graphene nanosheets. In this study, Novalak-graphene oxide (GO) gel was fabricated using solvent-saturated vapor... 

    The Synthesis of Graphene-Nanobubbles and Investigation of their Potential Synergistic Effect on Bacterial Cells

    , Ph.D. Dissertation Sharif University of Technology Jannesari, Marziyeh (Author) ; Akhavan, Omid (Supervisor) ; Maddah Hosseini, Hamid Reza (Supervisor) ; Bakhsi, Bita (Co-Supervisor)
    Abstract
    Recently, nanotechnology has promised to create and/ or improve therapeutic methods which in turn remain minimum side effects by employing synergistic effects of nanostructures. However, a comprehensive understanding of the interactions between nanostructures and building blocks of the biological systems (cells) is essential to create innovative therapeutic methods and compound and also predict their behavior for upcoming applications. In this thesis for the first time, synergistic effects of graphene-nanobubbles in interactions with bacterial (as the simplest model) cells were investigated. Therefore, at the first step, production of nanobubbles (NBs) in the presence of two-dimensional... 

    Luminescent Down Shifting of the Incident Spectrum to Enhance the Performance of Dye-Sensitized Solar Cell

    , Ph.D. Dissertation Sharif University of Technology Hosseini, Zahra (Author) ; Taghavinia , Nima (Supervisor) ; Mehrany, Khashayar (Supervisor)
    Abstract
    Luminescence down shifting (LDS) of the incident spectrum is a practical strategy that helps to increase the light harvesting efficiency by manipulating the incident spectrum instead of interfering with the active material inside the cell. In this research, for a dye-sensitized solar cell with a near-infrared sensitizer, the photovoltaic performance was enhanced remarkably with a reflective luminescent down-shifting (R-LDS) layer. Different inorganic phosphors with different luminescent quantum efficiencies have been used as the down shifting materials to increase the light-harvesting efficiency of DSSCs sensitized with TT1 and SQ1 dyes. Four different structures were examined to find the... 

    Design and Synthesis of Ni-Zn Magnetic Nanoparticles for Hyperthermia Treatment

    , Ph.D. Dissertation Sharif University of Technology Delavari, Hamid (Author) ; Madaah Hosseini, Hamid Reza (Supervisor) ; Simchi, Abdolreza (Supervisor)
    Abstract
    Hyperthermia (also called thermal therapy or thermotherapy) is defined as a type of cancer treatment in which body tissue is exposed to high temperatures, to damage and kill cancer cells, or to make cancer cells more sensitive to the effects of radiation and certain anticancer drugs. The temperature increase required by hyperthermia can be achieved via different heat sources, such as electromagnetic radiation waves (radiofrequency or microwave, ultrasound waves and electrical current. These techniques have shown good results, however, the major problem with present conventional methods is reaching homogenous heat distribution and therapeutic temperatures in the deep region of the tumor to be... 

    Study of Nanocrystallization Kinetics, Microstructure and Magnetic Properties of Finemet-type Soft Magnetic Materials

    , Ph.D. Dissertation Sharif University of Technology Asghari Shivaee, Hossein (Author) ; Madaah Hosseini, Hamid Reza (Supervisor) ; nozad, Ahmad (Supervisor) ; Beitollahi, Ali (Co-Advisor)
    Abstract
    Nanocrystallization kinetics of amorphous Finemet-type alloys was studied using Isokinetic and Isoconversional methods (Kissinger model-fitting method, Vyazovkin advance method, Kissinger–Akahira–Sunose(KSA),Flynn–Wall–Ozawa(FWO),Tang and Starink) under isothermal and non-isothermal conditions. Effects of chemical composition on the nanocrystallization kinetics, microstructure and magnetic properties of Fe73.5Si13.5B9Nb3Cu1 and Fe77Si11B9Nb2.4Cu0.6 alloys were also investigated. Kinetic triplet (activation energy, frequency factor and reaction model) were determined by these methods and compared for the alloys. According to isoconversional methods, the activation energy is variable as a... 

    Fully Automatic Segmentation of Pelvic CT Images based on Deep Learning Methods

    , M.Sc. Thesis Sharif University of Technology Ghaedi, Elnaz (Author) ; Hosseini, Abolfazl (Supervisor)
    Abstract
    The initial step in radiotherapy treatment planning involves delineating the clinical target volumes (CTVs) and organs at risk (OARs). However, manual contouring is a time-consuming, labor-intensive, and subjective process. This study explores the potential of utilizing convolutional neural networks (CNNs) as an automated segmentation tool and an alternative to manual delineation. 218 Computed Tomography (CT) scans were gathered from two local hospitals in Tehran and the Whole Abdominal Organ Dataset (WORD). We employed ResUNet, a variant of UNet, as well as the original UNet from the Medical Open Network for AI (MONAI), an open-source framework for Deep Learning (DL) in healthcare imaging,... 

    Comparative Study of Different Techniques for Calculation of Cell Survival Surve in Ion Therapy

    , M.Sc. Thesis Sharif University of Technology Karimi, Mehdi (Author) ; Hosseini, Abolfaz (Supervisor)
    Abstract
    Cancer is one of the leading causes of death around the world according to WHO. Scientists’ tried different approaches for treating this illness and from about 100 years ago one of the leading approaches to treat cancer is radiotherapy. With advancement of technology possibility of using different kinds of radiation for this purpose became available and one of the most interesting ones is high energy charged ions. But using high energy charged ions for treatment planning needs deep understanding of its nature and factors that affects the human body cells response to it. This thesis briefly reviewed the working principles of radiation therapy and then investigated two of the most used... 

    Evaluation of the Possibility of Diagnosing Female Gynecologic Cancer using X-Ray Fluorescence (XRF)Spectroscopy of Hair and Nail

    , M.Sc. Thesis Sharif University of Technology Jafari Iman, Fatemeh (Author) ; Hosseini, Abulfazl (Supervisor) ; Salimi, Ehsan (Supervisor)
    Abstract
    In recent years, indirect methods of cancer detection that utilize changes in trace element levels in various parts of the body, such as hair and nails, have garnered significant attention from researchers.The primary objective of these methods is to identify alterations in trace element levels that serve as biological markers in the presence of disease. While direct examination of affected organs remains the gold standard for cancer diagnosis, it is often expensive, time-consuming, inconvenient, and associated with potential side effects. Therefore, if the effectiveness of this approach is validated, it could serve as a cost-effective, non-invasive, safe, and early diagnostic method in... 

    Designing a System for Pulse Pile-Up Processing in Gamma Ray Spectroscopy Based on Digital Method

    , M.Sc. Thesis Sharif University of Technology Hojjat, Saeed (Author) ; Hosseini, Abolfazl (Supervisor)
    Abstract
    In Radiation Detection Systems applied in Spectroscopy and Imaging, if the rate of particle incidence with detector is high, the output pulses being stacked up on each other will be expected, which is known as “Pulse Pile-up”. Pulse pile-up might result in a serious disorder of energy and timing data expected from the pulses. In recent decades and after successful implementation of pile-up rejection methods on analog circuits, considering development and progression in the field of digital, different algorithms based on pileup correction methods have been developed to obtain all spectrum information, whether energy, rise time and recorded pulses. Such methods can be compared in different... 

    Development of Software Based on Statistical Iterative Algorithm in the Reconstruction of Sparse View CT images

    , M.Sc. Thesis Sharif University of Technology Jamaati, Sayna (Author) ; Hosseini, Abolfazl (Supervisor)
    Abstract
    X-ray Computed Tomography (CT) is a widely used medical imaging technique that provides cross-sectional images by measuring the attenuation of X-rays in the body. However, the increasing use of CT has raised concerns about the potential long-term risks associated with radiation exposure. Various approaches have been proposed to reduce radiation dose, and one of the latest methods is sparse-view CT, which has gained popularity due to its lower challenges compared to other techniques. In sparse-view CT, data acquisition is restricted to specific angles, resulting in a significant reduction in radiation dose. However, this approach can introduce streak artifacts in the reconstructed images due... 

    Investigation of Ocular Tumor Dose Enhancement in Proton Therapy in the Presence of Nanoparticles of Different Materials

    , M.Sc. Thesis Sharif University of Technology Alamgir, Jafar (Author) ; Hosseini, Abolfazl (Supervisor) ; Salimi, Ehsan (Supervisor)
    Abstract
    In recent years, the effect of the presence of nanoparticles in the tumor in order to increase the benefit of the treatment in radiation therapy has been the focus of many researchers. Although for photon irradiation, a significant dose increase due to the presence of nanoparticles has been observed, in the case of proton irradiation, due to the different nature of the beam and the lower cross-section of protons with metals compared to photons, scattered and in some cases contradictory findings have been published in the articles, and more studies are needed in this field. Due to laboratory limitations, Monte Carlo simulation is an appropriate tool for simulating difficult real-world... 

    Dose Reduction Via Development of a Novel Image Reconstruction Method for Few-View Computed Tomography

    , Ph.D. Dissertation Sharif University of Technology Khodajou Chokami, Hamid Reza (Author) ; Hosseini, Abolfazl (Supervisor) ; Ay, Mohammad Reza (Supervisor)
    Abstract
    Sparse-view computed tomography (CT) is recently proposed as a promising method to speed up data acquisition and alleviate the issue of CT high-dose delivery to patients. However, traditional reconstruction algorithms are time-consuming and suffer from image degradation when faced with sparse-view data. To address this problem, we propose two new frameworks based on deep learning (DL) that can quickly produce high-quality CT images from sparsely sampled projections and is able for clinical use. Our first DL-based proposed model is based on the convolution, and residual neural networks in a parallel manner, named the parallel residual neural network (PARS-Net). Besides, our proposed PARS-Net... 

    Presentation and Modeling of a New Nanocomposite Shield Against Gamma Radiation Based on Simulation and Computational Tools

    , M.Sc. Thesis Sharif University of Technology Arvaneh, Ali (Author) ; Hosseini, Abolfazl (Supervisor)
    Abstract
    In this study, using the MCNPX computer code based on the Monte Carlo method, the properties of protection against gamma-rays of the glass system with the combination of (55-x)Bi2O3-15Pb3O4-20Al2O3-10ZnO-xTiO2 with certain concentrations (x= 0, 5, 10, 15, 20, 25, 30 and 35 mol percent) and in nano and micro dimensions by calculating several parameters related to photon attenuation such as half value layer (HVL), Tenth value layer (TVL), mean free range (MFP), mass attenuation coefficient (m), linear attenuation coefficient (l), effective atomic number (Zeff) and buildup factor (BF) for We investigated different energy levels in the range of 1500-100 keV. To verify the simulation results,... 

    Discrimination of Neutron and Gamma Spectrum Using a Method Based on Digital Filters

    , M.Sc. Thesis Sharif University of Technology Valipour, Mahdi (Author) ; Hosseini, Abolfazl (Supervisor)
    Abstract
    Since the beginning of discussion on neutron-gamma discrimination, different methods were suggested for this purpose. In early 2000s, Analogue methods were mainly used to discriminate the spectrum in mixed fields which mostly depends on electronic modules used in the lab setup; Nowadays, with improvements in digital pulse processing techniques, analyzing mixed neutron-gamma fields for pulse discrimination is also available.In this research, the recent MC developed toolkit called GEANT4 is used to simulate the 3-inch BC501A scintillation detector and 500 mCi Am-Be source (that emits neutron and gamma at the same time). For the next step, an experiment with same source and detector was done... 

    Analysis of the Effect of Economic Variables on Effectiveness of Mobile Sources Air Pollutants Emission Control Policies: in the Case of Tehran

    , Ph.D. Dissertation Sharif University of Technology Hassani, Amin (Author) ; Maleki, Abbas (Supervisor) ; Hosseini, Vahid (Co-Supervisor)
    Abstract
    Passenger cars (PCs) are of particular importance among mobile air pollutants emissions sources due to their population and significant share in air pollutants emissions and gasoline consumption. Moreover, ownership and use intensity of PCs are affected by socio-economic situation. The present study projects the future trends of air pollutants emissions and fuel consumption from PCs in Tehran by 1415 and assesses the effect of economic situation on the emission trends and effectiveness of emission reduction polices. Accordingly, the present study develops an interdisciplinary modeling framework, which combines econometric models with a bottom-up emission estimation model to simulate the... 

    Simulation of Bushehr Nuclear Power Plant Hot Channel Using ANSYS CFX 18.0 Software

    , M.Sc. Thesis Sharif University of Technology Asadi, Ali Asghar (Author) ; Ghafari, Mohsen (Supervisor) ; Hosseini, Abolfazl (Co-Supervisor)
    Abstract
    In nuclear power plants, the fission reaction takes place inside the fuel rods, and the heat generated inside the fuel rods is transferred through the clad wall to the cooling fluid, which is single-phase, subcooled and in the turbulence zone. In the hot channel of the reactor core, where the axial and radial heat flux reaches its maximum state, the fluid leaves the single-phase state and some steam is formed in the area close to the clad wall.Therefore, in some cases, in the hot channel, the steam near the clad wall may reach a point that reduces the heat transfer coefficient, rapidly increases the wall temperature and thus destroys or melts the sheath surface. If this happens, it means...