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shamkhali--amir-naser
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Investigation of Thermodynamic Relations in Microscopic Systems by Quantum Information Theory
, M.Sc. Thesis Sharif University of Technology ; Shafiee, Afshin (Supervisor) ; Shamkhali, Amir Naser (Supervisor)
Abstract
Entropy is one of the important quantities in thermodynamics. In this project has tried to make this quantity as a bridge between quantum and thermodynamics. Entropy has many definitions that the Shannon entropy is chosen in this work. By this definition of entropy, we are able to define the entropy for a electronic system in molecules. By this definition, we are seeking an answer for this question,”whether entropy has a similar application in quantum like thermodynamics or not?”. To elucidate this hypothesis, simple diatomic molecules are computed. In fact, displacement of the Shannon entropy has investigated in bond making process. The question is that whether we can use this quantity to...
Presentation of a Model for Prediction of Ch4/Co2/H2s Permeation Through Polymeric Membranes
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Abbas (Supervisor) ; Maghsoudi, Vida (Co-Advisor) ; Shamkhali, Amir Naser (Co-Advisor)
Abstract
Acidic gases separation from hydrocarbon mixtures is very important in natural gas industry. In this study, the separation of CO2 and H2S from CH4 investigates by experimental and molecular dynamics simulation approaches. For achievement to this goal, it is used two polymeric families, as be divided to polyurethanes and PEBAX copolymers. It is used 4 polyurethane membranes as are named PU-1, PU-2, PU-Ether, and PU-Ester from polyurethanes group. Also, it is applied 5 PEBAX commercial membranes have be known PEBAX-2533, PEBAX-4033, PEBAX-5533, PEBAX-4011, and PEBAX-1074. It is compared between simulation and experimental works and found that there is good agreement between...
Calculation of the Thermodynamical Properties of [BMIM][PF6] via Equation of State and Molecular Dynamic Simulations Data
, M.Sc. Thesis Sharif University of Technology ; Parsafar, Gholamabbas (Supervisor) ; Tafazzoli, Mohsen (Supervisor) ; Shamkhali, Amir Naser (Co-Advisor)
Abstract
In this thesis, We have investigated the accuracy of general equation of state ( EoS III ) and linear isotherm regularity ( EoS I ), introduced on 2009 and 1993, respectively, and the Ghatee’s equation of state ( EoS II ) introduced on 2001, for the pvT data and thermodynamic properties of [BMIM][PF6] ionic liquid. We have carried out simulations at first in a narrow range of pressure, namely within 1-3400 atm and in temperature range from 398 K to 1000 K. The results of fitting of EoS I, EoS II and EoS III into the simulations results, leads to R2 > 0.9936, 0.9800 and 0.9949 respectively, for the pressure range of 1-3400 atm and for the temperature range of 398-1000 K. The results of...
Theoretical Investigation of Carbon Monoxide Adsorption on the Nickel Surface in the Macroscopic and Microscopic Scales
, Ph.D. Dissertation Sharif University of Technology ; Parsafar, Gholamabbas (Supervisor)
Abstract
In this work, CO interaction with macroscopic Ni(111) surface and microscopic Nin (n = 2-4) clusters were investigated. First, the CO interaction with various adsorption sites were studied by DFT methods on Ni(111) surface. On the basis of these calculations, hcp site has the strongest interaction with CO adsorbate. Then, the vibrational frequencies of C=O and adsorptive bond on the hcp site were calculated and the results show that anharmonicity of adsorptive bond is more important than C=O bond. Therefore, three potential models are considered for adsorptive bond and the effect of potential models on its thermodynamic properties was investigated. The results show that the effect of...
Theoritical Investigation of Metallic Cations and Gas Adsorption on Surface of Carbon Nanostructures
, Ph.D. Dissertation Sharif University of Technology ; Tafazoli, Mohsen (Supervisor) ; Shamkhali, Amir Nasser (Supervisor)
Abstract
Carbon nanostructures are of great importance in scientific and industrial research. Two case of the important two-dimensional carbon nanostructures are graphitic carbon nitride (g-C3N4) and graphene. In the first part of this work, adsorption of important heavy metal cations including Hg+2, Ag+, Cr+3, Pb+2, Cu+2, Ni+2, Cd+2, Tl+, Sb+3, Zn+2 and As+3 on the surface of (g-C3N4) was investigated by density functional theory (DFT). The main purpose of this theoretical study is to evaluate the ability of g-C3N4 to adsorb pollutant cations. The most prominent result of this work was the ability of g-C3N4 for effective adsorption of As+3 and Sb+3 ions from aqeous solutions. Also, another...
Wear Behavior of Cast Rods Manufactured for Hard Surfacing Iron Based Alloy
, M.Sc. Thesis Sharif University of Technology ; Kokabi, Amir Hossein (Supervisor) ; Varahram, Naser (Supervisor)
Abstract
Wear of parts during service is one of the main factors of damage to the industrial parts. From among various kinds of wear, abrasive wear has the most role in damage of industrial parts. Hard surfacing is a useful and cost effective method for improving the surface properties of parts. This method is made through coherent layer sediment from the alloys resistant to abrasion, oxidation and wear by welding or spray. Determining the appropriate alloy for hard surfacing operations need knowing of working conditions of the part and the type of occurred abrasion. Ordinarily, the alloys which are prepared for hard work by welding, are in the form of cored wire or electrodes. In this research die...
Feasibility Study and Conceptual Design of A Radioisotope Thermoelectric Generator
,
M.Sc. Thesis
Sharif University of Technology
;
Vosoughi, Naser
(Supervisor)
;
Feghhi, Amir Hosain
(Supervisor)
Abstract
Radioisotope thermoelectric generator (RTG) is a kind of nuclear batteries, in which thermal energy resulting from the discharge of charged particles decayed of radioisotope, using thermoelectric arrays, can be converted to electrical energy. In this study, the different kinds of RTGs introduced and applications of them have been expressed. All types of radioisotopes used in RTGs have been reviewed and the most suitable of them in terms of maximum thermal power density and minimum dose rate have been selected. All types of thermoelectrics used in RTGs have been reviewed and the most suitable of them in terms of the range of temperature and maximum efficiency have been selected.
In this...
In this...
Effect of side by side interactions on the thermodynamic properties of adsorbed CO molecules on the Ni(111) surface: A cluster model study
, Article Molecular Physics ; Volume 108, Issue 10 , 2010 , Pages 1397-1412 ; 00268976 (ISSN) ; Parsafar, G ; Sharif University of Technology
2010
Abstract
The effect of electrostatic interactions on vibrational frequencies and thermodynamic properties of CO adsorbate on the Ni(111) surface is calculated by taking the first and second nearest-neighbour interactions into account. In order to obtain reasonable results, the cluster model of various surface adsorption sites with CO adsorbate is partially optimized, using Density Functional Theory and also the MP2 method for the hcp site. Comparison between DFT and MP2 results shows that DFT results are more reliable for this system. The stretching and bending frequencies of CO adsorbate are calculated using both Partial Hessian Analysis and Cluster-Adsorbate Coupling methods. Stretching and bending...
Effect of model potential of adsorptive bond on the thermodynamic properties of adsorbed CO molecules on Ni(111) surface
, Article Journal of Physical Chemistry B ; Volume 110, Issue 41 , 2006 , Pages 20435-20444 ; 15206106 (ISSN) ; Parsafar, G ; Sharif University of Technology
American Chemical Society
2006
Abstract
The effect of anharmonicity on the adsorption of CO molecules on the Ni(111) surface has been investigated. The DFT calculations are used to obtain the effective adsorption potential of the CO molecule on the Ni(111) surface. First, using an appropriate slab model, the geometry of adsorption system corresponding to hep, fcc, bridge, and on-top sites with p(2 × 2) arrangement and coverage of 0.25 ML is optimized by the DFT calculations using a plane wave basis set and ultrasoft pseudopotentials; this gives the hep site as the most stable site with De = 185 kJ/mol, for which the equilibrium distance of CO from the surface and C-O bond length on the surface are found to be 1.31 and 1.192 Å,...
Studying the Factors Affecting Customer Satisfaction and Customer Loyalty from Customer Relationship Management Plans: Case of IranKhodro Company
, M.Sc. Thesis Sharif University of Technology ; Sepehri, Mehran (Supervisor) ; Karami, Naser (Co-Advisor)
Abstract
Results showed that 9 factors of “Brand Equity”, “Product Quality”, “Service Quality”, “Service Recovery”, “Perceived Value”, “Relationship”, “Employee Satisfaction”, “Physical Environment” and “Distribution Channel” are most effective factors by researchers that have effect on customer satisfaction. Thus, the Macromodel of this research was designed based on these factors. Due to limitations and context of the research, “Service Quality”, “Service Recovery” and “Relationship” were chosen in the final model. Results of questionnaire showed that the 5 parameters of “Service Recovery Speed”, “Reliability”, “Responsiveness”, “Empathy” and “Seller-focused antecedents” was the most important...
Determination of Optimum Material and Thickness of Filter Based on Radiation Energy in Digital Industrial Radiography (CR) Using MCNP Monte Carlo Simulation Code
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Naser (Supervisor) ; Rokrok, Behrouz (Supervisor) ; Movafeghi, Amir (Co-Supervisor)
Abstract
In this study, the effect of external filter on the various parameters of image quality in digital industrial radiography by CR method for steel and aluminum piece has been investigated. The filter reduces the noise of scattered beams by absorbing the low-energy beams in the X-ray spectrum that are most likely to be scattered, but high filter thicknesses can attenuate the more energetic beams and have a negatively effect on the image quality. On the other hand, the absorption of those low-energy beams increases the average spectrum energy and thus reduce the contrast, so it is necessary to use the appropriate material and thickness of the filter. For this purpose, to examine the filter...
Experimental Determination & Thermodynamic Modeling of Solubility of Gases in Ionic Liquids
,
M.Sc. Thesis
Sharif University of Technology
;
Ghotbi, Cyrus
(Supervisor)
;
Behzadi, Bahman
(Supervisor)
;
Jalili, Amir Hossein
(Supervisor)
;
Ahmadi, Amir Naser
(Co-Advisor)
Abstract
Ionic liquids (IL's) are found to be potentially suitable solvents for the chemical process industry, especially due to their negligible vapor pressure which can result in a major decrease of solvent loss and the environmental harm. One of the foreseeable industrial applications in the field of natural gas processing is the replacement of traditional organic solvents (usually alkanol amines) presently used for the absorption of H2S from sour gases, by suitable IL's. Ionic liquids have been proposed for the separation of gas mixtures. In particular, ionic liquids have been suggested for the removal of the acid gases, hydrogen sulfide, and carbon dioxide, from natural gases and refinery gases....
Modeling Cesium-137 Deposition and Absorption on Soil and Plants
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Naser (Supervisor) ; Movafeghi, Amir (Co-Advisor) ; Yahagi, Effat (Supervisor)
Abstract
Cesium-137 is one of the more important radionuclides in the environment because it is relatively abundant, it has a moderately long half-life (~30 y), its decay produces highly penetrating gamma radiation in addition to beta particles, and its biogeochemical properties allow it to move readily through food chains. It is a radioactive isotope of cesium which is formed as one of the more common fission product by the nuclear fission of uranium-235 and other fissionable isotopes in nuclear reactors and nuclear weapons.
In this reseach a model is introduced that could simulate a nuclear accident, its distribution into air, deposition into soil and absorption by plant. Nuclear accident and...
In this reseach a model is introduced that could simulate a nuclear accident, its distribution into air, deposition into soil and absorption by plant. Nuclear accident and...
Design and Fabrication of a Microfluidic Device to Study the Growth of Breast Cancer Cell
, M.Sc. Thesis Sharif University of Technology ; Vosughi, Manuchehr (Supervisor) ; Shamloo, Amir (Supervisor) ; Naserifar, Naser (Supervisor)
Abstract
for decades Cancer has been one of the major causes of death universally. Though extensive efforts in developing new anticancer therapies, they face failures in clinical trials and curing the sick owing to time consuming and expensive preclinical models with poor predictions of drug responses in human. To address this challenge it is crucial to develop preclinical models mimicking the main aspects of a tumor that can provide effective prediction of therapeutic responses. Tumor on chip technology has appeared as a promising approach for providing effective cancer models and reliable preclinical predictions. In this project, collagen was first extracted as the main constituent of the tumor...
Separation of Aromatic Component from Aliphatic Component by Using Task Ionic Liquid
, M.Sc. Thesis Sharif University of Technology ; Sayf Kordi, Ali Akbar (Supervisor) ; Ahmadi, Amir Naser (Supervisor)
Abstract
In this work 1-(2-hydroxyethyl)-3-methylimidazoliumbis{(trifluoromethyl) sulfonyl}imide ([hemim][NTf2]) and 1-benzyl-3-methylimidazoliumbis{(trifluoromethyl) sulfonyl}imide ([bzmim][NTf2]) ionic liquids were used to study the effect of introducing hydroxyl and benzyl groups to the imidazolium cation on aliphatic/aromatic separations. Toluene separation from heptanes has been investigated by extraction using ionic liquids. Finally, a realistic model for survey the data was used. The liquid-liquid equilibrium (LLE) data for the {heptane + toluene + [hemim][NTf2]}, {heptane + benzene + [hemim][NTf2]} , {heptane + toluene + [bzmim][NTf2]} systems were measured at 313.2 K and atmospheric...
Polar and low polar solvents media effect on dipole moments of some diazo Sudan dyes
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Vol. 127 , 2014 , Pages 340-348 ; ISSN: 13861425 ; Golghasemi Sorkhabi, Sh ; Shamkhali, A. N ; Sharif University of Technology
2014
Abstract
Absorption and fluorescence spectra of three Sudan dyes (Sudan III, SudanIV and Sudan black B) were recorded in various solvents with different polarity in the range of 300-800 nm, at room temperature. The solvatochromic method was used to investigate dipole moments of these dyes in ground and excited states, in different media. The solvatochromic behavior of these substances and their solvent-solute interactions were analyzed via solvent polarity parameters. Obtained results express the effects of solvation on tautomerism and molecular configuration (geometry) of Sudan dyes in solvent media with different polarity. Furthermore, analyze of solvent-solute interactions and value of ground and...
Effect of Ionic Liquids on the Process of Gas Hydrates Formation
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Siroos (Supervisor) ; Taghikhani, Vahid (Supervisor) ; Ahmadi, Amir Naser (Supervisor)
Abstract
In this study thermodynamics and kinetics effects of two ionic liquids (ILs) on the formation and dissociation of methane and carbon dioxide hydrates were investigated. The ILs used in this study are 1-butyle-3-metylimidazolium tetrafluoroborate, [Bmim][BF4], and 1-butyle-3-metylimidazolium methyl sulfate, [Bmim][MS]. At the first step of experimental section, the tetrahydrofuran (THF) was used in atmospheric pressure. The structure of THF hydrate is similar to natural gas hydrate; therefore it is used as a model for studying the properties and investigation of inhibitors effects on gas hydrates. In order to consider the effects of foregoing ILs on the formation and dissociation of gas...
A general model for I/O system theory, Proceedings of AIMC31 [electronic resource]
, Article Iranian Journal of Fuzzy Systems ; 2006, Volume 3, Issue 2, Page 1-19 ; Hashem, Amir ; Sharif University of TechnologyTrain Scheduling on a two-Way and Single Track Railway Line Considering the Train Stops for Prayer
, M.Sc. Thesis Sharif University of Technology ; Salmasi, Naser (Supervisor)
Abstract
Train scheduling is one of the most complicated stages of railway planning. In this stage, the arrival and departure times of trains at stations are determined. In this thesis, we studied train scheduling on a two-way and single track railway in order to minimize the total travel times of trains subject to a set of operational constraints and prayer time related constraints that determines the optimal station for prayer. In this project, we tried to simulate the real constraints exist in IRAN railway network and the objective function considers customer’s and railway management’s satisfaction, simultaneously. First, a mathematical programming is proposed for this problem. After demonstrating...
, Ph.D. Dissertation Sharif University of Technology ; Vosoughi, Naser (Supervisor)
Abstract
The present ph.D. thesis consists of three sections including the static calculation, neutron noise calculation and neutron noise source unfolding in VVER-1000 reactor core. The multi-group, two dimensional neutron diffusion equations and corresponding adjoint equations are solved in the static calculation. The spatial discretization of equations is based on Galerkin Finite Element Method (GFEM) using unstructured triangle elements generated by Gambit software. The static calculation is performed for both linear and quadratic approximations of shape function; baesd on which results are compared. Using power iteration method for the static calculation, the neutron and adjoint fluxes with the...