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    Fabrication of a Centrifugal Microfluidic System for Cell-free DNA Isolation from whole Blood as a Biomarker

    , M.Sc. Thesis Sharif University of Technology Hatami, Ali (Author) ; 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 Abdi, Parisa (Author) ; 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 Amirpoor, Setareh (Author) ; 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 Fakhri, Mohammad Ali (Author) ; 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 Navi, Hossein (Author) ; 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 Aharipour, Nazli (Author) ; 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 Madanchi, Parham (Author) ; 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... 

    Design of Methods for Synthesis and Immobilization of Nitrogen Ligands Such as Pyridine onto the Mesoporous Silica Nanoparticles and Design of Pharmaceutical Structures Based on Amino Acids and Carbohydrates to Inhibit Polymerase Η for the Treatment of Leukemia and their Applications In Resins and Ionic Liquids

    , Ph.D. Dissertation Sharif University of Technology Kalhor, Sepideh (Author) ; Matloubi Moghaddam, Firouz (Supervisor) ; Fattahi, Alireza (Supervisor)
    Abstract
    1- Mesoporous silica materials have been found to possess pore sizes ranging from 2 -10 nm alongside 2D-hexagonal and 3D-cubic structural features. The specific properties of nanoparticles of the mesoporous silica family, such as the collected size, porosity, morphology, and high chemical stability, make them among the best drug delivery systems and catalysts. Designing the catalysts with advanced structures that effectively locate the transition metals and create active centres onto the surfaces of mesoporous silica materials has attracted extraordinary attention. According to many studies, mesoporous silica materials without organic functional groups cannot be used as catalysts in chemical... 

    Evaluation of Exerted Drag Force on Alkane Saturated Air Bubbles in Aqueous Solutions by Experimental Studies

    , M.Sc. Thesis Sharif University of Technology Rajabzadeh Dezfuli, Mehdi (Author) ; Bastani, Dariush (Supervisor) ; Lotfi, Marzieh (Supervisor)
    Abstract
    Interfacial phenomena and properties of interphase surfaces in dynamic mode play an important role in industrial processes that include gas-liquid and liquid-liquid multiphase flows. As well as, interface knowledge leads to better understanding of natural and fundamental phenomena. The present study has been performed for understanding about dynamic behavior of interphase surfaces in the presence of nanoparticles and hexane vapor in gas-liquid dispersion systems. In this research, rising bubble method has been used as one of the most conventional techniques. Accordingly, aqueous solutions of nanosilica were prepared in concentrations of 50, 100, 200, 400 and 1200 ppm as continuous phase... 

    Investigation on Effect of Additives on the Synthesis of Mesoporous Silica Nano Particles for Drug Delivery Applications

    , M.Sc. Thesis Sharif University of Technology Askari, Majid (Author) ; Nemati, Ali (Supervisor) ; Akbari, Hmid (Supervisor) ; Khoobi Shourkaei, Mahdi (Co-Supervisor)
    Abstract
    In recent years, the use of mesoporous silica nanoparticles as carriers of biological agents has increased. The use of nanometer dimensions in intra-body applications not only hides the particles from the view of macrophages and the body's immune system, but also causes the particles to enter the cells more easily through endocytosis. Template removal method is the most common method in the synthesis of mesoporous silica. In this method, the orderly arrangement of pattern-forming molecules is used to form pores. Until now, various types of organic materials have been used as pattern materials. The main goal is the synthesis of nanoparticles with the largest size of holes and the largest... 

    Study of Self-Cleaning Silica Nano Coatings

    , M.Sc. Thesis Sharif University of Technology Hadinejad Sheikh, Farshad (Author) ; Afshar, Abdollah (Supervisor)
    Abstract
    It has always been a challenge to make self-cleaning coatings based on super-hydrophobic properties that can provide the necessary features to be operational in the industry. One of these necessary features is the ability to easily apply the coating on the substrate and reduce the cost by finding the optimal amount of consumables. Therefore, in this research, at first, it was tried to produce silica nanoparticles with a particle size of less than 011 nm using the Stober method, and then the surface of the synthesized nanoparticles was coated with HDTMS (Hexadecyltrimethoxysilane) to make the silica particles, which are hydrophilic in nature, hydrophobic. According to the conducted studies,... 

    Experimental and Analytical Study of Warpage Reduction in Polypropylene 3d Printing by using Recycled Silica Nanoparticles

    , M.Sc. Thesis Sharif University of Technology Ebadifard, Mohammad Reza (Author) ; Pircheraghi, Gholamreza (Supervisor) ; Tavakoli, Rohollah (Supervisor)
    Abstract
    Creating sustainable development in today's society is essential, and one of the most important elements to achieve this is the phenomenon of recycling. Lead-acid batteries are one of the sources of environmental pollution, and their separators contain 50% recyclable silica nanoparticles. In this research, impurities in these separators were removed using two methods: washing with water and sandblasting. The purity of recycled nanoparticles was 85.5% in the first method and 98% in the second method. In addition to the importance of recycling, finding a suitable use for recycled materials is also critical. FDM 3D printing is a new method of producing parts, but polypropylene is not commonly... 

    Investigation on Effects of Nanoparticles Presence on Hydrate Formation Characterization During Drilling

    , M.Sc. Thesis Sharif University of Technology Jalilolghadr Ardabili, Raouf (Author) ; Mohammadi, Ali Asghar (Supervisor) ; Zarenezhad, Bahman (Co-Advisor) ; Ramazani, Ahmad (Co-Advisor)
    Abstract
    In past two decades, the direction of oil and gas exploration has moved towards deep water drilling. The pressure and temperature in these zones are ideal for gas hydrate formation that can cause serious and sometimes uncontrollable issues during drilling operations. Gas hydrate formation while drilling can cause problems such as occurrence of kick and blowout, plug chock and kill line, and change in rheology of drilling mud. On the other hand, nowadays, nanotechnology has created an evolution in engineering sciences and because of the wide range of this science, drilling industry is affected like other industries. In the meantime, because of high yield, high stability and various methods of... 

    3D Bioprinting of Amniotic Membrane-Based Nanocomposite for Tissue Engineering Applications: Evaluation of Rheological, Mechanical and Biological Properties

    , Ph.D. Dissertation Sharif University of Technology Kafili, Golara (Author) ; Simchi, Abdolreza (Supervisor) ; Tamjid, Elnaz (Supervisor) ; Niknejad, Hassan (Co-Supervisor)
    Abstract
    3D bioprinting is an additive manufacturing method that facilitates the deposition of the desired cells and biomaterials at any pre-defined location. This technique also enables control over the internal structure and external dimensions of printed constructs. Among various biomaterials used as bioinks, the bioinks derived from decellularized extracellular matrixes (dECMs) have attracted significant attention due to their bioactivity and being a rich source of biochemical cues. Here in this study, the decellularized amnion membrane (dAM) has been selected as the main component of the bioink formulation because of its biocompatibility, low immunogenicity, antibacterial property, abundance,... 

    Mesoporous silica nanoparticles (MCM-41) coated PEGylated chitosan as a pH-Responsive nanocarrier for triggered release of erythromycin [electronic resource]

    , Article International Journal of Polymeric Materials and Polymeric Biomaterials ; 2014, Volume 63, Issue 13, Pages 692-697 Pourjavadi, A. (Ali) ; Mazaheri Tehrani, Zahra ; Sharif University of Technology
    Abstract
    A pH-responsive drug delivery system based on core shell structure of mesoporous silica nanoparticle (MSN) and chitosan-PEG copolymer was prepared and characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscope (SEM), and high-resolution transmission microscope (HR-TEM) techniques. In order to improve compatibility MSN and drug, mesoporous nanosilica was modified by 3-aminopropyl triethoxysilane. The release of erythromycin (a macrolide antibiotic) as a model drug was investigated in two pHs, 7.4 and 5.5  

    Efficient and practical protocol for silylation of hydroxyl groups using reusable lithium perchlorate dispread in silica gel under neutral condition [electronic resource]

    , Article Journal of Organometallic Chemistry ; 2006, Volume 691, Issue 5, Pages 817–820 Azizi, N. (Najmodin) ; Yousefi, R ; Saidi, M. R ; Sharif University of Technology
    Abstract
    A very efficient and mild procedure for the trimethylsilylation of a wide variety of alcohols, including primary, allylic, benzylic, secondary, hindered secondary, tertiary, and phenols with hexamethyldisilazane on the surface of silica gel dispersed with LiClO4 in room temperature at few minutes in excellent yields under neutral conditions is reported. This procedure also allows the excellent selectivity under LP-SiO2 system for silylation of alcohols in the presence of amine and phenolic hydroxy groups  

    Silica chloride/wet SiO2 as a novel heterogeneous system for the deprotection of acetals under mild conditions [electronic resource]

    , Article Phosphorus, Sulfur, and Silicon and the Related Elements ; Volume 178:2667-2670, Issue 12, 2003 Mirjalili, B. F. (BiBi Fatemeh) ; Pourjavadi, Ali ; Zolfigol, Mohammad Ali ; Bamoniri, Abdolhamid
    Abstract
    A combination of silica chloride and wet SiO2 was used as an effective deacetalizating agent for the conversion of acetals to their corresponding carbonyl derivatives under mild and heterogeneous condition  

    Monitoring the influence of dispersed nano-particles on oil-water relative permeability hysteresis

    , Article Journal of Petroleum Science and Engineering ; Vol. 124, issue , December , 2014 , p. 222-231 ; ISSN: 09204105 Parvazdavani, M ; Masihi, M ; Ghazanfari, M. H ; Sharif University of Technology
    Abstract
    In recent years, polysilicon nanoparticles are used to enhance the oil recovery through the water injection process in oilfields. The contributing mechanisms are the reduction of interfacial tension and wettability alteration which lead to improving or decreasing the oil phase relative permeability and can be traced by change of relative permeability curves. However, profound understanding of the effect of dispersed nano-silica particles on the hysteretic behavior of relative permeability curves remains a controversy topic in the literature.The current study illustrates the influence of dispersed silica particles on hysteretic trend of two-phase curves of oil-water relative permeability.... 

    Investigation of the effect of water based nano-particles addition on hysteresis of oil and-water relative permeability curves

    , Article Society of Petroleum Engineers - SPE International Oilfield Nanotechnology Conference 2012 ; June , 2012 , p. 267-277 Parvazdavani, M ; Masihi, M ; Ghazanfari, M. H ; Sherafati, M ; Mashayekhi, L ; Sharif University of Technology
    Abstract
    It has been shown that one kind of poly silicon particles with sizes ranging from 10-500 nm, can be used in oilfields to enhance the oil recovery of water injection by 15-20%. The contributing mechanism might be reducing the interfacial tension which appears through improving relative permeability of the oil-phase. However, fundamental understanding of how hysteretic behavior of relative permeability curves affected by nanosilica particles remains a topic of debate in the literature. In this study, water as well as water dispersed nanosilica particles floods was performed on sandstone rock sample saturated by light crude oil supplied from one of Iranian oil reservoir, and the relative... 

    Monitoring wettability alteration by silica nanoparticles during water flooding to heavy oils in five-spot systems: A pore-level investigation

    , Article Experimental Thermal and Fluid Science ; Vol. 40, issue , July , 2012 , p. 168-176 ; ISSN: 08941777 Maghzi, A ; Mohammadi, S ; Ghazanfari, M. H ; Kharrat, R ; Masihi, M ; Sharif University of Technology
    Abstract
    It is well known that the displacement efficiency of EOR processes is mainly affected by wettability of porous medium; however, the role of nanoparticles on wettability alteration of pores surfaces remains a topic of debate in the literature. Furthermore, a little is known about how the dispersed silica nanoparticles affect the microscopic/macroscopic recovery efficiency of heavy oils during common immiscible EOR processes such as water flooding. In this study, a series of injection experiments was performed on five-spot glass micromodel which is initially saturated with the heavy oil. Distilled water and dispersed silica nanoparticles in water (DSNW) at different values of weight percent...