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    Application of Diazonium Salts for Grafting the Sol-gel Based Sorbents: A New Approach Towards Unbreakable SPME

    , M.Sc. Thesis Sharif University of Technology Bayat, Parisa (Author) ; Bagheri, Habib (Supervisor)
    Abstract
    A novel application of diazonium salts for grafting the sol-gel based sorbents was sucessfully introduced. Preparation of unbrekable sorbents has been on highly demand and sough after by many researches for several years. However, there are a few achivements in this regard, but it still remains as a big challenge.Regarding to this issue, diazonium salts were sucessfully applied for functionalizing the different substrates, in which there is no limitation in selection of substrates. Different substrates, metallic and non metallic, such as copper, brass, stailess steel and PTFE were chosen to be functionalized by chemical or electrochemical reduction of 4-Amino phenyl acetic acid. Then,... 

    Mahaarloo Salt Lake Restoration Policy Study Using DPSIR Approach

    , M.Sc. Thesis Sharif University of Technology Shoorrahmati, Abdullah (Author) ; Abrishamchi, Ahmad (Supervisor)
    Abstract
    Lakes, marshes, and wetlands shrinkage and drying up due to natural and human driving forces is today one of the most important concerns in the world. Mahaarloo Salt Lake in southern part of Iran is (18 km far from south eastern of Shiraz ) drying-up and is faced with ecologic and environmental degradation. It recharges from western north by upstream basin of Shiraz and 3 rivers named Khoshk, Chenaarrahdaar, Soltaanabad and also from eastern south by Nazarabad river located in Sarvestan basin (Regional water org. of Fars 1382). In recent years, the shrinkage of Mahaarloo has been exacerbated by mismanagement of water resources, inappropriate land use, ignoring allocation of environmental... 

    Numerical Modeling of CO2 Sequestration in Nonhomogeneous (layered) Saline Underground Formations

    , M.Sc. Thesis Sharif University of Technology Naddafnia, Mohammad Reza (Author) ; Pak, Ali (Supervisor)
    Abstract
    Due to a rapid growth in the consumption of fossil fuels, the emission of greenhouse gases has multiplied in the atmosphere in the past few decades. This issue can directly affect on the rise of global temperature. Because of the intensification of the global warming, international organizations are looking for ways to reduce the greenhouse effect. One of these methods is injecting and trapping greenhouse gases, especially carbon dioxide, resulting from the operation of power plants and other large industries and preventing it from entering the atmosphere. The injection of carbon dioxide in underground salt water reservoirs can have various effects such as mechanical, hydraulic, thermal, and... 

    Integrated Geomechanical Modeling of Casing Failure; From Lab to Simulation

    , Ph.D. Dissertation Sharif University of Technology Taheri, Reza (Author) ; Pak, Ali (Supervisor) ; Shad, Saeed (Co-Supervisor)
    Abstract
    Casing failure is one of the mainly problems of hydrocarbon fields that may cause wells out of service and impose heavy costs on oil companies. There exist many theories that may cause casing failure including: the plastic behavior of surrounding formations, the effects of reservoir depletion, over-pressured formations, weak cementing operations, fault activation, and local stresses applied on casing. In salt-rich formations, creep behavior can be the main cause of casing failure, too.The purpose of this study is to evaluate the causes affecting casing failure via experimental studies and numerical simulation with the focus on the conditions governing south-west Iranian oil fields, where the... 

    Molecular Dynamics Simulation of Hydrogen Diffusion into Brine: Implications for Underground Hydrogen Storage

    , M.Sc. Thesis Sharif University of Technology Kalati, Saba (Author) ; Ayatollahi, Shahaboddin (Supervisor) ; Mahani, Hassan (Supervisor) ; Pourkhiabani, Nahid (Co-Supervisor) ; Esmaeilbeig, Mohammad Amin (Co-Supervisor)
    Abstract
    The high consumption of worldwide fossil energy and its detrimental effects on the environment and climate have prompted a transition toward renewable energy sources. The availability of renewable energy sources depends on weather and seasonal changes; therefore, an imbalance between supply and demand would be unavoidable. Hydrogen storage as an energy carrier, can fulfill this energy mismatch. Storing hydrogen in underground formations, such as aquifers, has been the subject of extensive research recently. In these storage reservoirs, hydrogen contacts the resident brine which will be lost through the dissolution-diffusion mechanism. Therefore, successful design of these storages requires... 

    Saltwater Up-coning into Pumping Wells in Coastal Aquifers in Fractured
    Soil

    , M.Sc. Thesis Sharif University of Technology Ebrahimi, Nazanin (Author) ; Ataie Ashtiani, Behzad (Supervisor)
    Abstract
    The goal of this research is to investigate the phenomenon of saltwater up-coning into pumping wells in fractured porous media. For this aim, two series of regular orthogonal fracture networks and different vertical and horizontal fracture apertures are simulated using an axisymmetric (2D vertical cross-section) model with a sharp interface approach. The effect of changing the pumping rate and the hydraulic conductivity has been examined to recognize other effective characteristics of the aquifer and pumping well on the saltwater up-coning. These simulations have been performed in COMSOL Multiphysics. The results indicate that the saltwater extent under the pumping well can be affected... 

    Synthesis of Dithiocarbamate Salts, Reaction of Divinyl Sulfone with Amines and CS2 & Polymerization of Diamines and CS2 with Michael Acceptors

    , M.Sc. Thesis Sharif University of Technology Raesi, Mozhgan (Author) ; Mahmoodi Hashemi, Mohammad (Supervisor) ; Ziyaei Halimjani, Azim (Supervisor)
    Abstract
    At the first part of project, different kinds of monodithiocarbamates were synthesized.In order to prepare these compounds two methods have been used:Reactions of amines and carbon disulfide in water and finally addition of Michael acceptors.Reaction of amines and carbon disulfide, then addition of alkyl halides under solvent-free conditions.Dithiocarbamate salts are prepared in ether by using CF3SO3CH3 as the methylation agent with resulted monodithiocarbamates at the first part of the project. These salts are found to be ionic liquids, which is important class of organic compounds.At the second part of project, the Michael additions of amines with divinyl sulfone are investigated in... 

    , M.Sc. Thesis Sharif University of Technology Khodabakhshi, Mohammad Reza (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    1,3-Dipolar cycloaddition reactions constitute one of the most fundamental reactions for construction of five-membered heterocyclic compounds Spiro and dispirooxindoles have become important synthetic targets as these structural frameworks form the core units of many naturally occurring molecules that possess abundant biological activities .In this report we used (E)-Aryl ideneindolinones as unusual dipolarophiles for synthesis of dispirooxindoles. In follow different bifunctional nucleophiles for example 1,3-dicarbonyl, phenol, thioindole can be used in synthesis of benzoxazocines We have reported a new and efficient synthesis of benzoxazocines via unique tandem 1,3-dinucleophilic addition... 

    Synthesis of Heterocyclic Compounds via Domino Knoevenagel Hetero Diels–Alder Reaction on Thiocarbonyls and Investigation of Tandem Dinucleophilic Addition on Pyridinium Salts

    , Ph.D. Dissertation Sharif University of Technology Kiamehr, Mostafa (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    In the first chapter, three efficient synthesis of novel polyheterocyclic indole and thiochromone-annulated thiopyranocoumarin derivatives are achieved via domino Knoevenagel hetero Diels–Alder reaction of O-acrylated and O-propargylated salicylaldehyde derivatives with indolin-2-thiones and 4-hydroxy dithiocoumarin. The domino Knoevenagel-hetero-Diels–Alder reactions are very efficient process that allows the formation of two or more rings at once, avoiding sequential chemical transformations. The products are formed in good-to-excellent yields with high regio- and stereoselectivity. The major advantage of this reaction is the ease of the work-up during which the products can be isolated... 

    Synthesis of Dithiocarbamate Derivatives and Their Applications to Prepare Heterocyclic Compounds

    , M.Sc. Thesis Sharif University of Technology Alaei Tazehgheshlagh, Mohammad Ali (Author) ; Saeedi, Mohammad Reza (Supervisor)
    Abstract
    Sulfur containing compounds are known as the most applicable group of organic compounds. Due to their medicinal and biological applications, dithiocarbamates are the most considerable among the many sulfur containing compounds. There are many procedures reported to synthesize these compounds as synthetic intermediates instead of thiophosgen and isothiocyanates. The reaction of amine and carbon disulfide is reported as the best and least hazardous way to synthesize this functional group. In this project heterocyclic compounds such as thiazoles, thiazolidine-2-thione, and 2-(alkylthio)thiazol-4(5H)-one derivatives were synthesized from the reaction of prepared dithiocarbamates with in situ... 

    Synthesis, Characterization and Voltametric Study of Single Molecule Magnet Hybrid Salts [Mn3O(O2CMe)6(Pyr)3][Keggin-Polyoxometalates]Type

    , M.Sc. Thesis Sharif University of Technology Kazemi Movahed, Leily (Author) ; Mohammadi Boghaei, Davar (Supervisor)
    Abstract
    Molecular nanomagnets, also known as Single Molecule Magnets (SMMs) are a class of molecules that at low temperature exhibit magnetic hysteresis of pure molecular origin and not related to a cooperative effect. In the past fifteen years they have attracted great interest for their potentiality to act as magnetic memory units and for the many quantum effects in the dynamics of their magnetization. Organization of SMM on surfaces is the first step in order to address the magnetic state of a single molecule or to connect the molecule to a conducting substrate. The complex nature of SMMs and the peculiar origin of their magnetic bistability have been representing for half a decade an obstacle to... 

    Preparing an Appropriate UF Membrane from PVC to Use it as Substrate in Sea Water Desalination RO Membranes

    , M.Sc. Thesis Sharif University of Technology Sabzi Dizajeyekan, Behnam (Author) ; Bastani, Daruoosh (Supervisor) ; Musavi, Abbas (Supervisor)
    Abstract
    In this study the main goal is preparing an appropriate UltraFiltration membrane from PolyVinyl Chloride for using as substrate in producing efficient Reverse Osmosis membranes to use in sea water desalination. each membrane should have some specifications to use it as reverse osmosis membrane’s substrate. One of the most important specifications is the appropriate pore sizes. To investigate this subject pure water flux and PolyEthylene glycol rejection of prepared membranes is tested. After investigation of this parameters and proving them, RO membranes are prepared using this membranes.
    Salt rejection of Brackish water (2000ppm) and sea water (Persian gulf,32000ppm) are measured in... 

    Hybrid Aqueous/Nonaqueous Electrolyte for Ca-Ion Batteries

    , M.Sc. Thesis Sharif University of Technology Noorsina, Saba (Author) ; Sadrnezhaad, Khatiboleslam (Supervisor) ; Yoozbashizadeh, Hossein (Supervisor)
    Abstract
    Water-in-salt (WIS) electrolytes with a wide electrochemical stability window (ESW) have made great progress in the field of aqueous batteries and capacitors. However, the slow diffusion of metal ions, such as lithium or calcium, has limited the use of these devices. Meanwhile, adding an organic co-solvent can improve the penetration of metal ions in salt water electrolytes. This electrolyte category, which has also used organic solvent in addition to water, is called organic/aqueous hybrid electrolyte modification. Since the effect of organic solvent on the performance of aqueous electrolyte in calcium batteries has not been investigated so far, in this research the physical and chemical... 

    , M.Sc. Thesis Sharif University of Technology Nourian, Saghar (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    Stachys species have played crucial role as a folk-medicinal plants since so many years ago. According to their commercial interest in the production of essential oils and flavoring agents, investigation through their secondary metabolisms still has been done. In the first part of this research, we have done our phytochemical investigation of Stachys inflata. The aerial parts of this plant have been collected; we could isolate and identify 5 molecules. Their structural elucidation was accomplished by extensive spectroscopic methods including 1H NMR, 13C NMR and 13C Dept experiments. In the second part of the research, we have reported a new and efficient synthesis of a broad spectrum of... 

    Preparation of Cobalt and Manganese Salts of Para-amino Benzoic Acid Supported on Graphene Oxide as an Oxidative Nanocatalysts

    , M.Sc. Thesis Sharif University of Technology Nasiri Kalkhoran, Shahrokh (Author) ; Mahmoodi Hashemi, Mohammad (Supervisor)
    Abstract
    In this thesis, a heterogeneous nanocatalyst based on graphene oxide was synthesized. To improve the graphene oxide, it was reacted with paraaminobenzoic acid and then metal salts (cobalt and manganese) were coated on it. The structure of the catalyst was confirmed by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), quantitative X-ray diffraction (EDS) and infrared (FT-IR) spectroscopy. Finally, the catalytic properties of the catalysts were evaluated in the oxidation reaction of different alcohols in the presence of oxygen. In the presence of benzyl alcohols with lethal electron groups, the oxidation conditions are stricter and the reaction efficiency is lower.... 

    Synthesis of Flavylium Perchlorate Salts via Reaction of Salicylaldehydes and Acetophenones Using Silica Gel.HClO4 Reagent.

    , M.Sc. Thesis Sharif University of Technology Ghonouei, nima (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    2-flavylium skeletons (2- Phenylbenzopyrylium salts), are often found as the basic structure in anthocyanins; the chromophores in natural pigments which are responsible for intense colors of fruits, leaves and flowers. They are present in plant organs, also to prevent them from environment predation and to protect the plant against ultraviolet irradiation especially in leaves. Aside from their contribution in plant parts, in industry, anthocyanines serve as food colorant, laser dyes and hair growing agents and have considerable biological and pharmaceutical activities like antioxidant, anti cancer, anti inflammatory, anti atherosclerosis, cardio protection and anti aging properties. almost... 

    Prediction of Thermodynamic Parameters in Solutions with Similar Composition to Plasma or Blood

    , Ph.D. Dissertation Sharif University of Technology Sadeghi, Masoud (Author) ; Abdekhodaie, Mohammad Jafar (Supervisor) ; Ghotbi, Cyrus (Co-Advisor)
    Abstract
    Serum osmolality is an important physiological quantity that is directly related to health condition of human body. Glucose, urea, and NaCl are the main components which determine the value of serum osmolality. Besides, calcium and potassium are vital inorganic cations for the body. Thus, it is of high importance to investigate the interactions between these physiological solutes in aqueous solution. Thermodynamic quantities like osmotic and activity coefficients contain enthalpic and entropic information and thus are a direct measure of interactions in these complex systems. Thus, theoretical and experimental methods were applied to investigate these thermodynamic parameters in multi-solute... 

    Analysis of Creep Behavior and Stability of Underground Fuel Storage in Rock Salt

    , M.Sc. Thesis Sharif University of Technology Narimani, Mohammad Ali (Author) ; Sadaghiani, Mohammadhosein (Supervisor)
    Abstract
    The purpose of this study is to analyze the stability and creeping behavior of rock salt in underground gas and oil reservoirs. Preparation of natural salt caverns and operating them can manipulate the initial state of previously existed stress and to produce deviatoric stresses around the cavern. New state of stress and with creeping behavior of rock salt, causes a significant decrease in cavern’s volume and damages the surrounding area. Reduction of internal minimum pressure of cavern, increases the intensity of mentioned problems. Geometrical characteristics of cavern can also be significantly effective in the magnitude of damages around the reservoir. For instance, Deflection of cavern... 

    Theoretical Analysis of the Electrochemistry and Power Generation in Thermally Activated Batteries

    , M.Sc. Thesis Sharif University of Technology Sharafi, Mona (Author) ; Gobal, Fereydoun (Supervisor)
    Abstract
    Study the potential and internal resistance of the electrochemical cells in different states of charge are important for practical and usage. Measurement of these parameters in an electrochemical cell is inseparably bound to the electrochemical resistance, temperature and also geometric states of different parts of the cell. In This project we focus on power and resistance of one kind of batteries called thermally activated batteries. These batteries are active after receiving heat and they are inactive at room temperature. Two of the most important models of these batteries that are discussed in this project are LiSi/ LiCl- KCl / FeS2 battery ( with liquid - molten salt electrolyte ) and... 

    Optimization the Performance of Multi-stage BNR Reactors Based on MBBR Reactor for Biological Removal of Nitrogen and Phosphorus in Saline Wastewater Refinery and Compared with Membrane Bioreactor Systems and USBF

    , M.Sc. Thesis Sharif University of Technology Delashoob, Abolfazl (Author) ; Borgheei, Mahdi (Supervisor)
    Abstract
    There are a lot of industry, including refineries with saline wastewater. Biological wastewater treatment saline pose particular problems and leads to plasmolysis microorganisms in the presence of salt. Remove salt from the wastewater before biological treatment by reverse osmosis or ion exchange and other methods are expensive and often impossible. Remove nutrients from wastewater before disposal and give up their saline for nature is essential. Because the these materials, especially nitrogen and phosphorus can degrade water quality and even make it unusable. So that by increasing the concentration of the algae production is also too much and cause eutrophication of water tanks are grown....