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hassani-monir--vahid
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Study of Phase Behavior and Economical Investigation on Transportation Of LNG and LPG Mixture
, M.Sc. Thesis Sharif University of Technology ; Badakhshan, Amir (Supervisor) ; Taghikhani, Vahid (Supervisor) ; Ghotbi, Siroos (Supervisor)
Abstract
Many technologies should be applied for transportation or consumption of natural gas. There are many different ways for transporting natural gas from origin of production to the location of consumption which the simplest way is transportation via pipelines but for transportation of natural gas for long distances, we can not use this method in this way we should apply other technologies such as converting the natural gas to the liquid state. For using this method, first we should liquefy the natural gas up to -162 degree of centigrade at the atmospheric pressure and then transport it with large cargo ships. By using this method, the transportation costs are decreased in compared with the...
Modeling of Natural Gas Components Hydrate Formation by Using Neural Network
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Siroos (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
In this study two approaches were applied to predict the hydrate dissociation pressure of natural gas in the presence of aqueous water. One approach applied van der Waals and Platteeuw solid solution theory & PR EOS the other applied a feed forward multi layers artificial neural network (ANN) with 19 input variables (temperature, existence of hydrocarbon liquid and ice phase, gas phase composition, inhibitor composition in aqueous phase), and one hidden layer with 17 neurons. In comparison of both methods it was concluded that, in temperature above 12℃ , ANN is more accurate than thermodynamic model, but in lower temperature thermodynamic model is comparable with ANN. The trained network...
preparation and Evaluation of Titanium Oxide sensitized in Visible Light for Obliterating of Pollutants
, M.Sc. Thesis Sharif University of Technology ; Kazemeini, Mohammad (Supervisor) ; Rashidzade, Mehdi (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
The Dye-sensitizers loading on TiO2 is decreasing the electron excitation energy and therefore improving the photocatalytic performance from the increasing the sensitivity under visible light irradiation.in this project CoPCTS , Mordant dye and N3(Ruthenium 535) used as dye-sensitizers. Also The addition of VIII group metals on TiO2 is improving the photocatalytic activity that increasing the photocatalytic reaction rate because of the intermediation role of them for moving the conduction band electrons to electron acceptors and increasing the pair electron-holes long-life that in this case Pt loading used as a VIII group metal. In this project Titanium Isopropoxide as a precursore and...
Optimum Ground State for Quantum Spin Chains
, M.Sc. Thesis Sharif University of Technology ; Karimipour, Vahid (Supervisor)
Abstract
In this thesis, we have studied some exact solutions for low dimensional strongly correlated systems, especially spin chains. In the first chapter using simple AKLT model and introducing Valence Bond Solid States we have prepared good area to study Finitely Correlated States. In addition to presenting relation between these concepts, we have expressed Matrix Product States as a simpler formalism to deal with Finitely Correlated States. In the second chapter we have discussed the Optimum Ground State concept and we have studied a spin-32 with nearest neighbor interaction and a spin-1 model with next nearest neighbor interaction
as example
as example
Measurement of Gas Permeation Though Carbonized Membranes and Determination of Mass Transfer Mechanisms
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Cyrus (Supervisor) ; Taghikhani, Vahid (Supervisor) ; Mahdyarfar, Mohammad (Supervisor)
Abstract
In this project, using experimental results for permeation of gases H2, He, N2, and CO on a microporous membrane (the applied sample was a ceramic membrane) and modified equations, pore diameter, tortuosity, and porosity were determined for this type of membrane. Furthermore, pore diameter, critical volume, and characteristic energy of a carbon molecular sieve membrane were calculated using experimental data for CO2 adsorption on this type of membrane. Diffusivities of CO2, N2, and Ar were also calculated by means of the uptake, time lag/adsorption, and permeability/adsorption tests on carbon molecular sieve membranes utilizing experimental data obtained for this type of membranes and the...
Constructing and Study of 1d And Quasi-1d Spin Models Through Matrix Product States Formalism (Mps)
, Ph.D. Dissertation Sharif University of Technology ; Karimipour, Vahid (Supervisor)
Abstract
Matrix Product States (MPS) is an analytical formalism to construct solvable many-body quan-tum models, which is based on the concepts of quantum information and computation theory. In this dissertation, We briefly review the history of matrix product states. We follow these states from quantum Markovian states(QMS) and valence bond solid states(VBS) to finitely correlated states(FCS) and matrix product states(MPS). We then present our method of study-ing and working with MP states and we introduce and study in detail the 1D and quasi-1D solvable spin models that we have been able to successfully construct in this frame work and calculate the corresponding correlations and quantities. These...
Two‐qubit Quantum State Sharing
, M.Sc. Thesis Sharif University of Technology ; Karimipour, Vahid (Supervisor)
Abstract
One of the problems that we are deal with in quantum information is secure transition of information. In Quantum State Sharing, we can encode our data on the quantum state and share the quantum state among some people such that none of the can be able to retrieve the state without collaboration with others. In this thesis, we will be concerned with reviewing of classical and quantum secret sharing and finally introduce another method in order to share a two qubit secret between N parties such any of the members can retrieve the state only with collaboration with other parties. It will be shown that using only Bell Pairs as recourse and measurement basis makes this model more efficient than...
Effect of Grinding and Shot Peening on Fatigue Life of Welded Joints
, M.Sc. Thesis Sharif University of Technology ; Farrahi, Gholamhossein (Supervisor)
Abstract
Metallurgical initial defects, stress concentration due to change in geometry and induced tensile residual stress during welding create an extraordinary high possibility of fatigue cracks nucleation and propagation in the weld toe region. Despite this, the ever increasing use of welding in offshore, aerospace and automotive industries, as the most applied mechanical joint, has occasioned a very extensive attempt to achieve an in-depth understanding of failure mechanisms and fatigue life improvement techniques of welded joints. Generally, these techniques could be classified into two broad categories. The first consists of methods that modify the geometry and the other is related to the...
Modeling of Fischer-Tropsch Synthesis Reactor for GTL Process
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Farhad (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
There is a need from the natural gas and energy industries to seek for an economically attractive way of converting remote gas reserves into transportable products, such as high quality fuels or petrochemicals. A possible way for the conversion of natural gas to middle distillates is based on a three-step process. Firstly, production of syngas from natural gas. Secondly,catalytic conversion of syngas into hydrocarbons, mostly parafins from C5 to C100. (Fischer-Tropsch (F-T) synthesis). Thirdly, hydrocracking of the heavy paraffinic hydrocarbons to middle distillates. The F-T synthesis step is highly exothermic. In order to control the temperature within the reactor, when considering high...
A Mixing Rule Based on WS Rule for Prediction of Phase Behavior of Polymer Solutions
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Cirus (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
The cubic equation of state (CEOS) is a powerful method for calculation of (vapor + liquid) equilibrium (VLE) in polymer solutions. However, the traditional mixing rules are not appropriate to extend the CEOS to non-ideal mixtures such as polymer solutions. For better prediction of (vapor + liquid) equilibria in polymer solutions, it is better to use mixing rules based on Excess Gibbs free energy function, GE. Choosing an appropriate excess Gibbs free energy for a mixing rule is a major step. In this work, by using three EOS (PRSV, Dashtizadeh and SRK) with FH-NRTL-NRF excess Gibbs free energy model and Wong–Sandler mixing rule, the EOS/GE method is applied for prediction of phase...
Kinetically Investigation of Catalyst Deactivation in Catalytic Reforming Process
, M.Sc. Thesis Sharif University of Technology ; Baghalha, Morteza (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
Catalytic reforming of naphtha is an important process to convert of low-octane number naphtha into high-octane number gasoline. Deactivation of catalysts, is the major problem for this process. In this study, catalytic reforming unit of Tabriz oil refinery investigated, and Smith’s kinetic model used for modeling. Also, several models presented for activity of catalysts. To find the parameters of presented models, the difference between the calculated and experimental values of outlet temperatures of each bed and aromatics, paraffin and naphthene yields simultaneously must be minimized. Using Genetic Algorithm Toolbox in Matlab software, optimization was performed and results indicated that...
Theoretical and Experimental Study of the Partitioning of Cephalexin in Aqueous Two Phase System of Polymer-Salt
, M.Sc. Thesis Sharif University of Technology ; Teghikhani, Vahid (Supervisor) ; Ghotbi, Cirouc (Supervisor) ; vossoughi, Manouchehr (Supervisor)
Abstract
The aqueous two phase systems provide a suitable environment for separation and purification of biological compounds. Because both phases are water rich and biomolecule remain active in them. In this work, the partition coefficients of Cephalexin in polymer-salt aqueous two-phase systems have been measured. The experimental results were obtained at three various temperatures (37.2, 34.2 and 28.2) C and in each temperature, two salt (K2HPO4, Na3Cit) and two polymer with different molecular weight (4000, 10000) are investigated. According to the two phase analysis, the effect of different factors on tie line of systems is studied. It is observed that with increasing the PEG molecular weight,...
Characterization and Modeling of Heavy Oil Fields Using Artificial Neural Networks to Optimize Horizontal Wells Selection
, Ph.D. Dissertation Sharif University of Technology ; Pishvaie, Mahmoud Reza (Supervisor) ; Taghi Khani, Vahid (Supervisor) ; Buzorgmehri, Ramin (Co-Advisor)
Abstract
Steam-Assisted Gravity Drainage (SAGD) is one of the best and the most effective methods of enhanced oil recovery (EOR) which is used in the production from Heavy Oil Reservoirs which constitute large amount of oil throughout the globe. In a typical process of SAGD, steam is injected into a horizontal well and the oil is produced several meters deeper in the ground. In order to increase the Recovery of this process, it is better to review on the Pre-heating methods around the injecting and producing wells. Pre-heating is important when the viscosity of the oil is large enough to prevent oil from any motion at the beginning of the SADG operation, and makes it necessary to to use a Pre-heating...
Capacity of Memory Quantum Channels
, M.Sc. Thesis Sharif University of Technology ; Karimipour, Vahid (Supervisor)
Abstract
One of the most important problems of quantum information theory is to try to determine the channel capacity of noisy quantum channels. Alice would like to send Bob information over many uses of a noisy quantum communication link. As the line is usually noisy, this cannot be done perfectly, and so they must use suitable coding methods to minimize the error. Different coding methods yield different rates of information transition and different errors, the channel capacity is defined as the maximum rate at which information may be transferred with vanishing error in the limit of a large number of channel uses. There are a variety of different capacities, depending upon whether Alice and Bob...
Experimental and Theoretical Study of Methane Adsorption on Multiwall Carbon Nano Tubes
, M.Sc. Thesis Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Ghotbi, Siroos (Supervisor)
Abstract
In this project, theoretical and experimental study of methane adsorption on Multiwall Carbon Nano-Tubes (MWCNT) has been performed. This study has been conducted in the way to achieve a suitable method for methane storage and transportation. To carry out the experiments, the volumetric method was used up to 500 psia at various temperatures of 298.15 K, 303.15 K, 308.15 K. The effect of moisture was also studied at 298.15 K. Also, various adsorption isotherms were used to model the experimental data collected in this work. The results showed that the amount of methane adsorbed on the MWCNT can decrease with increasing the moisture and temperature of the adsorption cell. In order to...
Enhancing Umbrella Activities in Agile Methodologies
, M.Sc. Thesis Sharif University of Technology ; Ramsin, Raman (Supervisor)
Abstract
The adaptive nature of agile processes and their conformance to the turbulent nature of business and organizational environments has been greeted with enthusiasm by both project and stakeholder communities. Through deviating from conventional linear and plan-driven frameworks, Agility aims at accommodating the dynamicity of its target environment at the process level during the project lifecycle. This deviation from standard frameworks confronts process management and project framework activities with key challenges. While existing frameworks and standards provide adequate support for linear process management, the agile approach lacks a coherent framework that defines and outlines process...
Experimental Study and Thermodynamic Modeling of Process Partitioning of Penicillin in Polymer-Salt Aqueous Two-Phase Systems
, Ph.D. Dissertation Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Vossoughi, Manouchehr (Supervisor)
Abstract
In this research, the partitioning of Penicillin G-Acylase in aqueous two-phase systems (ATPS) containing poly ethylene glycol (PEG) 20000 or 35000 and potassium di-hydrogen phosphate (KH2PO4) or sodium citrate (C6H5Na3O7.5H2O) is measured at three temperature (301.2, 307.2 and 310.2) K. The effects of temperature, polymer molecular weight, polymer and salt concentrations on partitioning of Penicillin G in the aqueous two-phase systems are studied. The experimental data showed that composition of salt has a large effect on partitioning of Penicillin G in ATPS and temperature of system has small effect on the partitioning. The modified local composition model was used to obtain the activity...
Studying the Behaviour and Performance of an Innovative Floating Offshore Platform
, M.Sc. Thesis Sharif University of Technology ; Khonsari, Vahid (Supervisor)
Abstract
The objective of this project is to study the behaviour and performance of an innotative floating offshore platform. Such Platform not only can be used for exploring oil from offshore fields, but for creating artificial islands, where land is in short supply. Due to its specific and, at the same time, simple geometry (symmetric), its fabrication does ont involve much complexity. Studies carried out on this platform include the investigation into its structural behaviour under gravitational (including self weight) and bouyancy forces. Studied cases include a number of platforms with different (geometrical) sizes and under 3 various bouyancy conditions (percentage), namely 1) 50% of the height...
Developing a Group-Contribution Thermodynamic Model Based on the SAFT-Type Equation of State for Solvent-Polymer Systems
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Cyrus (Supervisor) ; Taghikhani, Vahid (Supervisor) ; Behzadi, Bahman (Supervisor)
Abstract
The usual method for determination of pure component parameters of SAFT-type Equation of State (EoS) is to fit them to experimental vapor pressure and liquid density data. Since high-molecular-weight compounds, like polymers, do not have a detectable vapor pressure, there is a need for a predictive calculation method for parameters of polymers and other complex compounds. In 2008, Tihic et al. proposed a Group Contribution (GC) method for estimating molecular parameters of PC-SAFT EoS. In this thesis, it is attempted to extend the suggested method of Tihic et al. by adjusting molecular parameters of PC-SAFT EoS for about 120 new non-associating compounds using experimental data extracted...
The Study of The Behaviour of Steel Structures with Semi-Rigid Connections Subject to Fire
, M.Sc. Thesis Sharif University of Technology ; Khonsari, Vahid (Supervisor)
Abstract
Fire is one the events which threatens the very existence of every building, residential, office, industrial or else. However, this threat is more serious with regard to buildings with steel structures. Steel, despite its many advantages over other structural materials, such as having high strength to weight ratio, ductility, toughness and resilience, has the disadvantage of rapidly losing its strength at elevated temperatures, i.e. in fire. Therefore, it is the responsibility of the designer to make the serious decision of whether to use steel, concrete, timber, or other materials for the structure of the building to be designed. Observations made during full-scale fire tests as well as...