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Fabrication and Thermal Analysis of Superhydrophobic Nano-textured Condensation Substrates
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Ali (Supervisor) ; Asghari, Mohsen (Supervisor)
Abstract
This thesis is a research corresponding to Super-Hydrophobic condensation substrates with Nanometer texture. In this study, the foresaid surfaces are fabricated by two methods that are Nano-composite paint and Electrophoretic coating. As a summary for the first method (the Super-Hydrophobic Nano-composite paint), the hybrid coating contains two mineral and organic phases; The organic phase is a two-part clear-coat polyurethane and plays the role as a polymer matrix in Nano-composite structure. Silica Nano-particles are the mineral phase and the two phases of Nano-composite have made connection with silane compounds. Also, surface-modification in Nano-particles for giving hydrophobicity...
Superhydrophobic Materials as Nanosorbents for Extraction Methodologies
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
In the first work, a superhydrophobic polystyrene hollow fiber (PS–HF) was synthesized by electrospinning and used in microextraction of trazine herbicides from aquatic media followed by gas chromatography mass spectrometric (GC–MS) determination. Effects of different parameters influencing the extraction efficiency including the solvent extraction and its amount, the desorbing solvent and its amount, extraction time and ionic strength were optimized. The characteristic properties of the hollow fiber were studied by scanning electron microscopy (SEM). The limits of detection and quantification of the method under optimized condition were 2 and 6 ng L-1, respectively. The relative standard...
Experimental Investigation of Improvement of Stability and Performance of Foam Using Nano-particles to Enhance Oil Recovery
, M.Sc. Thesis Sharif University of Technology ; Ghazanfari, Mohammad Hossein (Supervisor)
Abstract
Using foam for reducing undesirable effects of fingering and gravity segregation in enhanced oil recovery through gas injection has attracted a rapidly increasing interest in recent years. Lack of stability of foam often limits its application. However there is a lack of systematic study of effects of unmodified and in-situ modified silica nano-particle on foam stability and foam behavior in the presence and absence of oil and also polymer effects from the prospective of analysis of foam dynamic stability, size of foam bubbles, and foam flow behavior in Hele – Shaw cell. Main objectives of this study are mechanistic investigation of effects of polymer – surfactant systems and in-situ...
Theoretical and Experimental Investigation of Interaction between Nanoparticles and Carbonate Porous Media
, Ph.D. Dissertation Sharif University of Technology ; Ghazanfari, Mohammad Hosseini (Supervisor) ; Jamialahmadi, Mohammad (Supervisor) ; Helalizadeh, Abbas (Supervisor) ; Kazemeini, Mohammad ($item.subfieldsMap.e)
Abstract
In recent years, application of silica nanoparticles for wettability alteration of reservoir rocks as an effective approach in enhancing oil recovery from petroleum reservoirs is introduced. However, in this area, lack of fundamental studies to provide a clear understanding about the interaction between these nanoparticles and carbonate rocks (as the predominant reservoir rocks in the world and Iran), which is of particular importance, is sensed. Therefore, the main purpose of this dissertation is to present a mechanistic investigation about the interaction of silica nanoparticles (the most used nanoparticles) with carbonate rock from theoretical and experimental viewpoints. To better...
Synthesis of Amphiphilic Nanoparticles with Different Alkyl Chains and their Application in Enhanced Oil Recovery
, M.Sc. Thesis Sharif University of Technology ; Mohammadi, Ali Asghar (Supervisor)
Abstract
Important features of the nanoparticles properties are their high superficial area and being able to reform their surface. In this study, the repairable property used to reform surface of silica nanoparticles (Those are used more frequently than other nanoparticles). Repairing of surface are doing to use nanoparticles as a surface-active material in enhanced oil recovery. Silane compounds with different chain length are used to create hydrophobic nanoparticles and PEG compounds are used to create hydrophilic nanoparticles. Also amphiphilic nanoparticles are created with a combination of both hydrophilic and hydrophobic compounds. To investigate the usefulness of nanofluids are made up of the...
studying the Effect of Adding Nanoparticles in Polymer/salt Aqueous Two Phase Systems for Separating of Alpha-amylase Enzyme
,
Ph.D. Dissertation
Sharif University of Technology
;
Vossoughi, Manoochehr
(Supervisor)
;
Pazuki, Gholamreza
(Supervisor)
Abstract
The effects of adding nanoparticles in partitioning of α-amylase in polymer/salt aqueous two phase system (ATPS) was studied in this research. First the binodal curves of magnesium sulfate salt with PEGs 2000,3000,4000,6000 and 10000 at 23 ° C has been plotted and the suitable system which was PEG 6000/ magnesium sulfate has been selected for studying the partitioning of enzyme. Thereupon the partition coefficient of α-amylase was measured and then effect of adding silica and graphene oxide nanoparticles was investigated. It was observed that nanoparticles caused a dramatic increase in partition coefficient and yield recovery (of top phase). For further investigation the partitioning of...
Febrication of Superhydrophobic Nanocomposites Containing Modified Silica Nanoparticles and Silicone Polymers and Evaluation of Their Application
, M.Sc. Thesis Sharif University of Technology ; Pourjavadi, Ali (Supervisor) ; Alamolhoda, Ali Asghar (Supervisor)
Abstract
Rehabilitation usually involves physical therapy, occupational therapy and counseling for the patient's morale to help to restore his power and performance. Considering the economic outlook and the costs of rehabilitation methods and due to the increasing prevalence of stroke and the need to recover the patients in a short period, only the use of robotic systems opens the door to the medical community. Since a large rehabilitation robots designed and built and each been used according to their advantages and shortcomings. In this project, the major shortcomings examined and exoskeleton designed on two major features including portability and covering shoulder workspace. Shoulder movement was...
Synthesis of Silica Nanoparticles Modified with Alumina and Its Performance in Compressive Strength of Concrete
, M.Sc. Thesis Sharif University of Technology ; Sajadi, Ali Akbar (Supervisor) ; Ghanbari, Bahram (Supervisor)
Abstract
Silica nanoparticles is one of the most important mineral particles. In this study, Sodium silicate, Sulfuric acid and Sodium aluminate is used in order to synthesis of the modified Silica nanoparticles. The effects of temperature, reaction time and the molar ratio of regents were tested and optimized. Synthesized nanoparticles were characterized by use of XRD, FT-IR and SEM techniques. The results show that by controlling the reaction conditions, nanoparticles with an average size of 26.2 nm is obtained. The increase of temperature and reaction time alters the structure of the particles of amorphous state to a crystalline needles. The particle surface modification process was performed by...
PVDF/SiO2 Nanocomposite Coating with Different Wettability in Contact with Oil and Water for phase Separation Propose
, M.Sc. Thesis Sharif University of Technology ; Dolati, Abolghasem (Supervisor)
Abstract
increased cohesion up to 4H pencil. Results of immersion test in water showed stability of coatings. Polarization test in naphtha and water mixture for stainless steel, copper and aluminum meshes demonstrated 98.89%, 86.25% and 66.6% protection efficiency respectively. In order to study of oil and water separation efficiency, mixtures of water and naphtha with different content of naphtha were used. Separation test for 200μm St.St mesh in different slopes demonstrated that changing of slop increase separation efficiency up to 95.5% for water and up to 100% for naphtha. Separation test for meshes with different pore size demonstrated that meshes with small pore size are more appropriate for...
The stereoselective synthesis of the tetrahydrothiopyranolr ,Y'-blindole skeletons via tandem reaction of indoline- r-thiones to Baylis-Hillman adduct acetates & Silica-Supported DABCO-tribromide: A New, Versatile and Recyclable Catalyst for the Chemoselective Oxidation of Sulfides to Sulfoxides and Oxidative Coupling of Thiols into Disulfides
,
M.Sc. Thesis
Sharif University of Technology
;
Matloubi Moghaddam, Firouz
(Supervisor)
Abstract
We have reported a new and efficient synthesis of tetrahydrothiopyrano [2,3-b]indole skeletons via unique tandem reaction of indoline-2-thiones to Baylis-Hillman adduct acetates. This protocol is a very mild and simple method for construction heterocycles in a one-step process. This is a convenient and diastereoselective synthesis of methyl 4-aryl-2,3,4,9-tetrahydrothiopyrano[2,3-b]indole-3-carboxylate systems in the presence of K2CO3 in acetonitrile. The major benefits of the current study are the one-pot procedure, high yields and diastereoselectivity, short reaction times and the similarity of the products to the biologically active moieties.
In addition 1, 4-diazabicyclo [2.2.2]...
In addition 1, 4-diazabicyclo [2.2.2]...
Manufacturing and Investigating of Polypropylene/Silica Nanocomposites via in-situ Polymerization and Using Bi-supported Ziegler-Natta Catalyst
, M.Sc. Thesis Sharif University of Technology ; Ramezani Saadat, Ahmad (Supervisor)
Abstract
The main object of this thesis is production and investigation of polypropylene-fumed silica nanocomposites by using bi-supported Ziegler-natta catalytic system and in-situ polymerization. Magnesium ethoxide and fumed silica were used as supports of catalyst. TiCl4 was accompanied by triisobutyl aluminum(TiBA) and diisobutyl phthalate(DIBP) as electron doner constituting Ziegler-Natta catalytic system. Preparation of catalyst and polymerization were taken place in slurry phase under the argon atmosphere. At the beginning of the polymerization experiment, several type of nanocomposites were made under various conditions(such as different Al/Ti molar ratio) to find optimum condition to...
Synthesis and Characterization of Smart Silica Nanocomposites via Reversible Addition−Fragmentation Chain-Transfer (RAFT)Polymerization
, M.Sc. Thesis Sharif University of Technology ; Pourjavadi, Ali (Supervisor)
Abstract
Photochromism is defined as a reversible transformation of a chemical species between two forms having different absorption spectra induced in one or both directions by photoirradiation. Numerous photochromic molecules were investigated such as spiropyrans (SP), spirooxazines (SO), fulgides, diarylethenes, and azobenzenes. Recently, spirooxazines have been attracted more attention due to their more sensitivity towards photo, pH, heat, pressure, solvent polarity, and high fatigue resistance. Spirooxazine moieties are one of the most popular photochromic groups that can be transformed from colorless closed ring form (SO from) to blue color open ring form by UV irradiation that so-called;...
Pore-Scale Investigation of the Effect of Fracture and Mineralogy on Formation Damage Caused by Drilling Fluid
, M.Sc. Thesis Sharif University of Technology ; Mahani, Hassan (Supervisor) ; Masihi, Mohsen (Supervisor)
Abstract
Formation damage in petroleum engineering is an important and fundamental phenomenon. During drilling operation, penetration of either the solid phase of drilling fluid or the base-fluid into the porous medium, reduces the permeability of the formation. While most experiments in the literature have focused on core-scale and beyond, there is lack of pore-scale studies. Moreover, presence of fractures has an undeniable effect on the extent of formation damage. Thus, the main objective of this dissertation is to investigate the effects of fractures on the severity of formation damage caused by the water-based drilling fluid and the mechanisms of formation damage at the pore scale, using glass...
Fabrication of a Centrifugal Microfluidic System for Cell-free DNA Isolation from whole Blood as a Biomarker
, M.Sc. Thesis Sharif University of Technology ; Saadatmand, Maryam (Supervisor) ; Garshasbi, Masoud (Co-Supervisor)
Abstract
Today, medical science has come to the conclusion that the best time to start treating a disease is in its early stages. Therefore, the topic of early detection has been widely welcomed in scientific circles. Today, one of the safest methods for early detection in medicine is the study of biomarkers. These biomarkers include CTC, cfRNA, cfDNA, Exosome, etc. For instance, in the discussion of early cancer detection, the US Food and Drug Administration has so far identified two biomarkers, cfDNA and CTC, as the safest markers. The cfDNA marker is also widely used not only in the diagnosis of cancer, but also in the field of sex diagnosis and fetal Down syndrome in the first weeks of pregnancy....
Fabrication of Porous Electrospun Fibe on Biocompatible Polymers such as Polycaprolactone (Pcl) and Thrs Based eir Application in Sample Preparation
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
The aim of this study was to develop a method to determine the trace residual amounts of nonsteroidal anti-inflammatory drugs in meat-related samples and to study the effect of different cooking methods and storage conditions of meat before cooking as an effective factor on the fate of these drugs. To proceed this goal, a nanocomposite was prepared from polycaprolactone nanofiber/silica mesopores as green sorbent by electrospinning. The synthesized nanocomposite was implemented for micro-solid phase extraction of the desired drugs in conjunction with high performance liquid chromatography. Polycaprolactone, due to its excellent physical properties, availability, biodegradability,...
Synthesis and Characterizes of Superoleophobic Coating on Stainless Steel
, M.Sc. Thesis Sharif University of Technology ; Dolati, Abolghasem (Supervisor)
Abstract
The main objective of this project was to create some coatings with different wettability properties of water and oil on the 304 stainless steel mesh In order to achieve phase separation. With the aim of creating a hydrophilic property, Various resin such as SILRES BS29, PDDA PDMS-OH, PDMS-NH2 was used individually or mixed. Furthermore, silica and TiO2 nanoparticles were used to make surface roughness. Perfluorooctanoic acid with 15 fluorine atoms in its molecular structure were added to solution to create the effect of superoleophobic. The contact angle and the slip angle measurements tests were performed. morphology and structure of nanocomposite coating study by FESEM microscopy and...
Fabrication of Superhydrophobic Coating to Reduce Drag force with Anti-Corrosion and Anti-biofouling Properties
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Ali (Supervisor)
Abstract
Growth of the fuel consumption in the world and the greenhouse effect of its pollution get industrial managers and environmental activities attention. Skin drag force has a significant role in energy uses. The drag reduction property of superhydrophobic surfaces shows a new approach for investigators to reduce energy uses. Surface with 150° contact angle called superhydrophobic surface.In this project, a superhydrophobic coating is developed based on acrylic hydroxyl resin by silica nanoparticles. This coating can be sprayed on any surface. Using the Iron oxid particles and silica nanoparticles together produces hierarchical micro-nano structures. This coating has a 160.1° contact angle on...
Preparation of Magnetically Recyclable Silica Supported Oxovanadium Nanocatalyst and its Application in the Oxidation of Sulfides
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
Current study reports a state-of-the-art approach for synthesis of nanocatalyst based on Oxo-vanadium Schiff base complex which itself is, covalently, immobilized on core-shell magnetic nanoparticles of silica-modified magnetite (Fe3O4@SiO2) and the substantial potential it offers as heterogeneous catalyst in selective oxidation of sulfides.Synthesized materials and complexes in this project were characterized by means of modern spectral devices such as FT-IR, XRD and SEM.Unlike routine process of the preparation of heterogeneous catalysts that requires further modification of the core-shell nanoparticles with capping agents, here we have been capable of cutting some time-consuming steps...
Synthesis of Fe3O4@ SiO2 Core-shell Magnetic Nanoparticles with Porous SiO2 Shell Extracted from Rice Husk Ash
, M.Sc. Thesis Sharif University of Technology ; Nemati, Ali (Supervisor)
Abstract
Magnetic nanoparticles, especially magnetic nanoparticles with silicate coatings, have attracted the attention of many researchers; Mainly because the silica shell can be functionalized with different molecules and functional groups and used in biological applications as targeted drug carriers. This study aimed to synthesize Fe3O4 core-shell nanoparticles with continuous and porous SiO2 shells on the surface of Fe3O4 particles. So that the coating is done evenly and with a strong connection. The procedure was as follows: core nanoparticle individual nanoparticles were made by the single-step method. To extract silica from rice husk, rice husk was subjected to heat treatment to obtain rice...
Investigation of Formation Damage with Oil-Based Mud (Invert Emulsion) Using Microfluidic Method
, M.Sc. Thesis Sharif University of Technology ; Mahani, Hassan (Supervisor)
Abstract
Formation damage is one of the most important challneges in hydrocarbon production; drilling mud invasion is one of its common types. This damage is caused by the penetration of the drilling fluid into the porous media, which its filtrate and solid pareticles block the pores and cause permeability reduction. The main purpose of this thesis is to investigate the pore-scale mechanisms of the formation damage induced by invert-emulsion drilling fluid and to investigate the effect of adding nanoparticles to the drilling fluid on the severity of the damage using microfluidic technique. According to the latest published articles, there has not been any research conducted at the pore-scale with...