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Fabrication and Optimization of Organic Inorganic Perovskite Solar Cells Using Vapor Phase Deposition
, Ph.D. Dissertation Sharif University of Technology ; Taghavinia, Nima (Supervisor) ; Tajabadi, Fariba (Supervisor)
Abstract
In this research, we focus on study and fabrication of organic inorganic solar cells. We use and optimize various methods such as one-step spin-coating, two-step sequential deposition and vapor-assisted solution process (VASP), to prepare high quality perovskite films. One-step deposition is simplest method for deposition of perovskite films. Although perovskite deposition by this method is very simple, the control of uniformity and surface film morphology is difficult. Chlorine inclusion, optimization of annealing conditions, and a sequential solution-based deposition method have been demonstrated to increase film coverage and uniformity. Hence, we use sequential deposition method for...
The semi-analytical modeling and simulation of the VAPEX process of ""Kuh-e-Mond"" heavy oil reservoir
, Article Petroleum Science and Technology ; Vol. 29, issue. 5 , Oct , 2009 , p. 535-548 ; ISSN: 10916466 ; Masihi, M ; Kharrat, R ; Sharif University of Technology
2009
Abstract
The vapor extraction process (or VAPEX) uses vaporized solvents injected into a horizontal well to form a vapor chamber within the reservoir. Vapor dissolves in the oil and enhances the oil production by decreasing the oil viscosity in heavy oil reservoirs. To evaluate the process we conduct a simulation study on an Iranian heavy oil reservoir called Kuh-e-Mond. In addition, a semi-analytical investigation of the VAPEX process has been performed. The idea is to perform VAPEX simulation for a laboratory model and find a methodology to compare the results of the simulator with the semi-analytical Butler's model. In particular, a semi-analytical dimensionless correlation for production rate...
The semi-analytical modeling and simulation of the VAPEX process of "Kuh-e-Mond" heavy oil reservoir
, Article Petroleum Science and Technology ; Volume 29, Issue 5 , 2011 , Pages 535-548 ; 10916466 (ISSN) ; Masihi, M ; Kharrat, R ; Sharif University of Technology
2011
Abstract
The vapor extraction process (or VAPEX) uses vaporized solvents injected into a horizontal well to form a vapor chamber within the reservoir. Vapor dissolves in the oil and enhances the oil production by decreasing the oil viscosity in heavy oil reservoirs. To evaluate the process we conduct a simulation study on an Iranian heavy oil reservoir called Kuh-e-Mond. In addition, a semi-analytical investigation of the VAPEX process has been performed. The idea is to perform VAPEX simulation for a laboratory model and find a methodology to compare the results of the simulator with the semi-analytical Butler's model. In particular, a semi-analytical dimensionless correlation for production rate...
Shaping of Laser Pulse for Molecular Dissociation
, M.Sc. Thesis Sharif University of Technology ; Saddighi Bonabi, Rasoul (Supervisor)
Abstract
In this project, ionization and dissociation of nitrogen, methane and formaldehyde molecules through interaction by intense femto-second lasers have been investigated. The optimum shape of laser pulses for dissociation of methane and formaldehyde molecules for controlling the dissociation paths into desired products are obtained. Based on time dependent density functional theory and quantum optimal control theory, the calculations are carried out in intensities at the range of 1014-1016 Wcm-2 with pulse durations of 4 -20fs. Octopus package is used as a powerful computational program. By using, quantum optimal control theory, optimum laser pulses with manipulation of amplitude, phase and...
Investigation of Quantum States of Light (Generation and Utilization Their Special Properties) in Quantum Information Science and Precision Measurements
, M.Sc. Thesis Sharif University of Technology ; Karimipour, Vahid (Supervisor)
Abstract
Quantum entanglement and superposition are wonderful and mysterious phenomena of quantum mechanics. By means of quantum entanglement, two or more systems become partner in state of each other . As a result, measurements on each of these systems affect the status of other systems. Quantum superposition allows a system inhabits several of its possible quantum states simultaneously. These two features are applicable in many technologies in present age. Photons, as an quantum unit of light, are appropriate candidate for utilization these properties. Because they are robust to decoherence and for their preparation exist various methods. Hence, we interested to generation of quantum states of...
Optimal control of dissociation of nitrogen molecule with intense ultra-short laser pulse shaping
, Article Journal of Molecular Structure ; Volume 1083 , March , 2015 , Pages 121-126 ; 00222860 (ISSN) ; Irani, E ; Sadighi Bonabi, R ; Sharif University of Technology
Elsevier
2015
Abstract
(GraphPresented) The quantum optimal control theory in conjunction with time dependent density functional theory is used to optimize the laser pulse shape for dissociation of nitrogen molecule. For several initial peak intensities and frequency ranges, the optimum shapes are produced and compared to determine the most efficient pulse. Ehrenfest molecular dynamics model is also used to test the dissociation process. The corresponding snapshots of density and time dependent electron localization function are presented. It is noticed that when the frequency ranges of laser pulses are doubled, it leads to 60% faster dissociation of N2 molecule
Efficient photo-dissociation of CH4 and H2CO molecules with optimized ultra-short laser pulses
, Article AIP Advances ; Volume 5, Issue 11 , 2015 ; 21583226 (ISSN) ; Irani, E ; Sadighi Bonabi, R ; Sharif University of Technology
American Institute of Physics Inc
2015
Abstract
The fragmentation dynamics of CH4 and H2CO molecules have been studied with ultra-short pulses at laser intensityof up to 1015Wcm-2. Three dimensional molecular dynamics calculations for finding the optimized laser pulses are presented based on time-dependent density functional theory and quantum optimal control theory. A comparison of the results for orientation dependence in the ionization process shows that the electron distribution for CH4 is more isotropic than H2CO molecule. Total conversion yields of up to 70% at an orientation angle of 30o for CH4 and 65% at 900 for H2CO are achieved which lead to enhancement of dissociation probability
Context-Aware ontology-based security measurement model
, Article Journal of Information Security and Applications ; Volume 67 , 2022 ; 22142134 (ISSN) ; Aref, M. R ; Rasti, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Security measurement models (SMMs) and quantitative security metrics (QSMs) are crucial pillars of systematic security measurement. How to design the enhanced SMMs and effective QSMs has been seriously considered in recent years. However, to the best of our knowledge, a desirable SMM has not yet been provided to measure the security effectiveness of a national-level network (NLN) due to its specific attributes. NLN has three main attributes, including plurality and diversity of network components, continuous changes, and simultaneous functionalities. These attributes cause three major challenges to designing a desirable SMM for NLN, including complexity, dynamic measurement, and...
Comprehensive comparison of security measurement models
, Article Journal of Applied Security Research ; 2022 ; 19361610 (ISSN) ; Aref, M. R ; Rasti, M ; Sharif University of Technology
Routledge
2022
Abstract
Security measurement models (SMMs) and their corresponding derived metrics form the main pillars of a systematic security measurement. Providing a desirable SMM is very challenging and has been investigated over the past two decades, so that numerous SMMs have been proposed and several surveys on SMMs have been performed. However, to the best of our knowledge, neither a systematic taxonomy nor a comprehensive comparison has yet been proposed for SMMs. This paper focuses on the comprehensive comparison of SMMs relying on a feature-based approach. The plurality and diversity of the compared SMMs enable us to deduce all the open issues. © 2021 Taylor & Francis Group, LLC
Comprehensive Comparison of Security Measurement Models
, Article Journal of Applied Security Research ; Volume 18, Issue 3 , 2023 , Pages 333-401 ; 19361610 (ISSN) ; Aref, M. R ; Rasti, M ; Sharif University of Technology
Routledge
2023
Abstract
Security measurement models (SMMs) and their corresponding derived metrics form the main pillars of a systematic security measurement. Providing a desirable SMM is very challenging and has been investigated over the past two decades, so that numerous SMMs have been proposed and several surveys on SMMs have been performed. However, to the best of our knowledge, neither a systematic taxonomy nor a comprehensive comparison has yet been proposed for SMMs. This paper focuses on the comprehensive comparison of SMMs relying on a feature-based approach. The plurality and diversity of the compared SMMs enable us to deduce all the open issues. © 2021 Taylor & Francis Group, LLC
Plug and play augmented HQS: Convergence analysis and its application in MRI reconstruction
, Article Neurocomputing ; Volume 518 , 2023 , Pages 1-14 ; 09252312 (ISSN) ; Ghaffari, A ; Fatemizadeh, E ; Sharif University of Technology
Elsevier B.V
2023
Abstract
Sparse recovery in the context of the inverse problem has become an enormously popular technique in reconstructing various degraded images in various applications. One of the well-known techniques in modularizing these particular inverse problems is the Plug and Play Half-Quadratic-Splitting (PnP-HQS). This method has been demonstrated to achieve good results in the literature; however, it is still too plain to be fully exploited for reconstruction. In this regard, we introduce an augmented version of this technique dubbed “PnP-AugHQS” to efficiently utilize its capabilities in image reconstruction. We provide a comprehensive convergence analysis of the proposed algorithm to ensure its...
A Study on Action Selection Deficits in Schizophrenic Patients Using Computational Modeling in Reniforcement Learning Framework
, M.Sc. Thesis Sharif University of Technology ; Vosoughi Vahdat, Bijan (Supervisor) ; Bahrami, Fariba (Supervisor)
Abstract
Schizophrenia is a devastating disorder that steals the opportunity of having a normal life from the sufferers. Drugs used in treating this disorder usually target psychotic symptoms and do not affect negative symptoms effectively. One of the deficits falling into this category is the impaired reversal learning. These patients usually learn the rules but do not renounce them after the contingencies of reward have been reversed. To investigate the reasons of this impairment, first a hypothesis of how different parts of the brain communicate during reversal learning is proposed using the physiological evidence. Then considering the known relation between the actor-critic model of the...
Semi-Analytical Modeling And Simulation Of Heavy Oil Recovery Through VAPEX Process
, M.Sc. Thesis Sharif University of Technology ; Masihi, Mohsen (Supervisor) ; Kharrat, Riyaz (Supervisor)
Abstract
VAPEX is a relatively new EOR process for the recovery of heavy oil. In this process solvent is used to form a vapor chamber within a reservoir. Vapor dissolves in the oil and diluted oil drains by gravity to a horizontal production well. The essential features of this recovery mechanism have been discussed in this study. Furthermore, a semi-analytical and a simulation study of VAPEX process have been performed on a specified Iranian heavy oil reservoir (such as Kuh-e-Mond). The aim of this study is to investigate an exponential functionality (correlation) witch incorporates all physical parameters that affect the production rate of VAPEX process in dimensionless form. The adjustable...
Determination of Stable Crystal Structure of Y358 New Superconductor and its Phonon and Electronic Structure using Density Functional Theory
, M.Sc. Thesis Sharif University of Technology ; Khosroabadi, Hossein (Supervisor) ; Akhavan, Mohammad (Co-Advisor)
Abstract
Y-based Superconducting compounds (YBCO) with different stoichiometry have been considered by researchers for its transition temperature above the boiling temperature of liquid nitrogen, preparation of high quality samples, simple crystal and electronic structure and other advantages relative to the other high-Tc copper oxide superconductors. Reaching to higher transition temperature has been considered in the recent years. In 2009, new compound of this family with different stoichiometry Y3Ba5Cu8O18(Y358) and transition temperature above 100 K was synthesized which is 10 K higher than maximum transition temperature in this family. Confirming this transition temperature can be help us for...
Analysis of DNA Methylation in Single-cell Resolution Using Algorithmic Methods and Deep Neural Networks
, M.Sc. Thesis Sharif University of Technology ; Sharifi Zarchi, Ali (Supervisor)
Abstract
DNA methylation in one of the most important epigenetic variations, which causes significant variations in gene expressions of mammalians. Our current knowledge about DNA methylation is based on measurments from samples of bulk data which cause ambiguity in intracellular differences and analysis of rare cell samples. For this reason, the ability to measure DNA methylation in single-cells has the potential to play an important role in understanding many biological processes including embryonic developement, disease progression including cancer, aging, chromosome instability, X chromosome inactivation, cell differentiation and genes regulation. Recent technological advances have enabled...
Improvment of Perovskite Layer and Perovskite/Hole Transport Layer Interface to Inhance Perovskite Solar Cell Performance
, Ph.D. Dissertation Sharif University of Technology ; Taghavinia, Nima (Supervisor) ; Tajabadi, Fariba (Supervisor)
Abstract
The use of renewable energy sources has received much attention due to the increasing need for energy, limited energy resources and the pollution of fossil fuels. Among all types of solar energy conversion technology, photovoltaics has the highest technical potential and Iran’s geographical location is very suitable for benefiting from this energy. So, in this thesis, the fabrication and characterization of nanostructured solar cells based on organic-inorganic perovskites have been investigated. Many research goups have tried to increase the efficiency of perovskite solar cells. The efficiency of this kind of solar cells depends mainly on the light-absorbing layer (perovskite) and its...
Synthesis and Characterization of ZnO for Electron Transport Layer in Perovskite and CIGS Solar Cells
, M.Sc. Thesis Sharif University of Technology ; Taghavinia, Nima (Supervisor) ; Dehghani, Mehdi (Supervisor)
Abstract
The purpose of this study is the fabrication and characterization of ZnO nano particles and the application of ZnO in solar cells. Therefore, firstly we fabricate the high stable solution of ZnO nano particles and then characterize ZnO nano particles. In addition, we study sulfurzation and selenization of zinc oxide thin films. We use ZnO nano particles for fabrication of transparent conductive films. Transparent conductive films have many applications such as touch panels, displays and solar cells. The most applicable transparent conductive electrode is indium tin oxide , which is the most expensive layer in solar cells. But silver nanowires has some challenges such as high surface...
Enhancing Supersaturation Processes in the Fabrication of Perovskite Solar Cells Using Ionic Liquids
, Ph.D. Dissertation Sharif University of Technology ; Taghavinia, Nima (Supervisor) ; Tajabadi, Fariba (Supervisor)
Abstract
Perovskite solar cells (PSCs) have emerged as a promising photovoltaic technology due to their high power conversion efficiency, ease of fabrication, relatively low production cost, and compatibility with various scalable deposition techniques. Nevertheless, several critical challenges including sensitivity to moisture and ambient oxygen, long-term instability, and the widespread use of toxic anti-solvents during film fabrication still hinder the large-scale commercialization of PSCs. Achieving perovskite layers with high crystalline quality, uniform and stable morphology under ambient conditions, and without employing harmful chemicals is a key bottleneck for industrial development. The...
Printable Carbon Electrode for Perovskite & Thin Film Solar Cells
, Ph.D. Dissertation Sharif University of Technology ; Taghavinia, Nima (Supervisor) ; Tajabadi, Fariba (Supervisor) ; Mohammadpour, Raheleh (Supervisor)
Abstract
Solar cells, as a part of photovoltaics (PV) industry, have a significant share in the renewable energy market. Perovskite solar cells (PSCs) and thin film solar cells (TFSCs) achieved 23% and 22% power conversion efficiencies (PCEs) respectively. However, the PV industry still faces challenges like “high manufacturing costs” and “stability”. Among the strategies to overcome these challenges are substitution of the costly materials with cheaper, more abundant ingredients along with utilizing inexpensive deposition methods like printing rather than vacuum-based methods such as evaporation and sputtering. Carbon materials attract more attention in the solar cell research community for their...
Conductive nanofiber scaffold for bone tissue engineering
, Article 24th Iranian Conference on Biomedical Engineering and 2017 2nd International Iranian Conference on Biomedical Engineering, ICBME 2017, 30 November 2017 through 1 December 2017 ; 2018 ; 9781538636091 (ISBN) ; Mashayekhan, S ; Abbaszadeh, H. A ; Ansarizadeh, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
In order to fabricate nanofiber scaffold for bone tissue engineering, electrospinning technique was employed. This technique produces nanofiberous scaffold supporting cell adhesion, migration, and proliferation. Here, we developed a novel conductive scaffold from poly-caprolactone, gelatin, and poly aniline/graphene nanoparticles. In this study, co-electrospinning was utilized to fabricate composite electrospun scaffold. The effect of polyaniline/graphene (PAG) nanoparticles on the mechanical properties and electrical conductivity of this hybrid scaffold was investigated. The result showed that PAG nanoparticles enbance both mechanical properties and electrical conductivity of the scaffolds....