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    Investigation of Excitation-contraction behavior in Skeletal Muscle by Means of Chemomechanical Modeling

    , Ph.D. Dissertation Sharif University of Technology Karami, Mina (Author) ; Zohoor, Hassan (Supervisor) ; Firoozbakhsh, Keikhosrow (Supervisor)
    Abstract
    Numerous studies have shown a direct relationship between skeletal muscle active force and intracellular calcium ion concentrations; In fact, no matter how the muscle is stimulated (neurological, electrical, chemical, and mechanical stimuli), the main cause of muscle activation and consequently force generation is calcium ions.According to this scientific finding, the purpose of this study is to present a new chemo-mechanical multiscale model of skeletal muscle based on the fundamental principles of continuum thermodynamics. In this model, unlike other similar studies, muscle active force is not considered as the conventional multiplication of isometric force in a set of corrective... 

    Preparation and Modification of Lithium-ion Battery Membrane/Separator

    , M.Sc. Thesis Sharif University of Technology Javadi, Omid (Author) ; Soltanieh, Mohammad (Supervisor) ; Mousavi, Abbas (Supervisor) ; Fathollahi, Abolfazl (Co-Supervisor)
    Abstract
    Electrolyte separator is the major component of lithium-ion batteries which the battery safety directly depends on it. In this work, a membrane separator based on the polyvinylidene fluoride (PVdF) was prepared via non-solvent induced phase separation (NIPS) method with water and ethanol as non-solvent and a mixture of dimethylformamide (DMF) and acetone as solvents. The effect of various acetone/DMF ratios and type of non-solvent on the structural, mechanical and electrochemical properties of separator was studied. The separator was characterized by FE-SEM, tensile strength, electrochemical AC-impedance spectroscopy, thermal stability and linear sweep voltammetry (LSV). Additionally, the... 

    The Study of Quark-Gluon Plasma by Flow Harmonics in Heavy Ion Collisions

    , Ph.D. Dissertation Sharif University of Technology Mehrabpour, Hadi (Author) ; Rouhani, Shahin (Supervisor) ; Arfaei, Hesamoddin (Supervisor)
    Abstract
    A new phase of matter which is known as quark-gluon plasma is created after ultrarelativistic nucleus-nucleus collisions. Experimental data imply that hydrodynamic equations can explain this new phase of matter. On the other hand, observations show that the geometry of initial energy distribution fluctuates event-by-event, even in a given centrality class. Also, the geometry of initial state distribution reflects itself as different samples of final particle spectrum results by the hydrodynamic evolution. The particle momentum distribution can be expanded by Fourier series which its coefficients called harmonic flows. We can only study the effects of hydrodynamics on initial fireball by flow... 

    Synthesis and Characterization of Graphene/Tin (IV) Sulfide (SnS₂) Hybrid Nanostructures as Anode Material for Ionic Batteries

    , M.Sc. Thesis Sharif University of Technology Haji Bagheri, Majid (Author) ; Esfandiar, Ali (Supervisor)
    Abstract
    In the current century, an energy storage is one of the critical and important factors affecting on human life. Rechargeable batteries, specially Lithium ion batteries (LIBs), can be considered as ideal energy storage devices including various advantages e.g. high energy and power densities. In this work, Tin IV sulfide (SnS2) and its composites, making by conductive materials e.g. Reduced Graphene Oxide (SnS2@rGO), are prepared during two different synthesis methods consisting of Hydrothermal and Hot-bath, and their properties are investigated as anode material in LIB. The structural and electrochemical analyses demonstrated that the composite sample prepared by hot-bath method exhibited... 

    Investigation of Interface Phenomena in Low Salinity/Smart Waterflooding by Applying Molecular Dynamics Simulation

    , Ph.D. Dissertation Sharif University of Technology Badizad, Mohammad Hassan (Author) ; Ayatollahi, Shahab (Supervisor) ; Ghazanfari, Mohammad Hossein (Supervisor) ; Koleini, Mhammad Mehdi (Co-Supervisor)
    Abstract
    Low salinity/smart waterflooding is simple to apply and a promising enhanced oil recovery method in which ion-tuned saltwater is injected into subsurface oil reservoirs. Many aspects of this operation, in particular those pertaining to nano-scale, are not yet fully understood. The present dissertation is an attempt to shed light on the microscopic properties and behavior of rock/brine/oil interfaces throughout low salinity/smart waterflooding. Several simulations were carried out for oil/brine and calcite/brine categories each containing various ions and hydrocarbons compounds. The surface contribution of non-functional oil compounds (aromatics and aliphatics) near brine medium was... 

    Design of Monitoring and Control System for Ion Implanter Gases

    , M.Sc. Thesis Sharif University of Technology Baharian, Hossein (Author) ; Rashidian, Bijan (Supervisor)
    Abstract
    Very dangerous gases are used in ion implanter machines. Opening and closing the valves of these gases can be very dangerous. In this project, these valves are inspected, monitored and opened and closed from a safe distance. To do this, we must monitor and control the above system by using the latest and most efficient technologies available and with the least delay. For accurate and precise monitoring, clear images should be obtained from the location and changes should be detected, and the device can be controlled very quickly with the necessary commands. To do this, one must have an accurate and comprehensive knowledge of processors and communication protocols, and also pay attention to... 

    Numerical Simulation and Modeling of Electrochemical Processes in Lithium Titanate Oxide Batteries

    , M.Sc. Thesis Sharif University of Technology Hassani, Elham (Author) ; Rajani Ghahnavieh, Abbas (Supervisor) ; Torabi, Farshad (Co-Supervisor)
    Abstract
    Batteries have always been used as one of the most important sources of electricity storage and supply. Among different types of batteries, lithium-ion batteries are widely used in various fields and engineering applications due to their high-density energy/power, high discharge/charge rate, and long life. The most common of these applications are using these batteries in all-electric and hybrid vehicles, which reduce environmental problems. Due to the high cost of these types of batteries and the environmental issues of battery decomposition, researchers are seeking to discover long-lasting batteries that lithium titanate oxide batteries have the most extended lifespan among lithium-ion... 

    Co-precipitation Synthesis Parameters of Lithium-rich Cathode Material

    , M.Sc. Thesis Sharif University of Technology Seraji, Pardis (Author) ; Sadrnezhaad, Khatiboleslam (Supervisor)
    Abstract
    Electric vehicles and electronics such as laptops and smartphones require an efficient amount of energy conversion and storage. As one of the reliable systems in this field, lithium-ion batteries have high energy density and lower emissions. Cathodic material is a bottleneck in the development of lithium-ion systems due to its high cost and limited energy capacity. In this study, lithium-rich oxide cathode was synthesized in the liquid phase using the co-precipitation synthesis method using six-aqueous nickel nitrate and four-aqueous manganese chloride precursors. The material was analyzed by structural characterization analysis as well as electrochemical characterizations. In this project,... 

    Synthesis of Graphene and its Application for Adsorption of Cobalt and Strontium Ions, and as an Electrode in Electrochemical Cells (Battery)

    , M.Sc. Thesis Sharif University of Technology Jalilzadeh, Hassan (Author) ; Outokesh, Mohammad (Supervisor) ; Hosseinpour, Morteza (Co-Supervisor)
    Abstract
    Although much progress has been made in eliminating, conserving, and reducing migration and emissions of radioactive materials, the risk of radioactive material release into the environment is still one of the most important hazards in the use of nuclear energy. In this study, graphene compounds have been used as adsorbents for the removal of radioactive materials due to their high level, cost-effectiveness and simplicity of the synthesis process of various composites. In this regard, the removal of strontium and cobalt by graphene compounds has been investigated. Magnetite nanoparticles were anchored on the surface of graphene by sol-gel method and adsorption in batch mode was investigated.... 

    Monitoring of Ion Implanter Radiation

    , M.Sc. Thesis Sharif University of Technology Malekian Sourki, Mehrdad (Author) ; Rashidian, Bizhan (Supervisor)
    Abstract
    X-ray radiation is an ionizing radiation that can be produced under some conditions in an ion implanter and can have significant effects on equipment and personnel health. In this dissertation, we first examine the properties of ionizing radiations and their effects of electronic devices and discuss the general properties of common detectors. Next, Using Silvaco TCAD and GEANT4 we will simulate the interaction of ionzing radiation with energies up to 300 keV with electronic devices including a commercial off the shelf photo diode and a specialized x-ray detector and show that these devices can efficiently reveal informations of a radiation source to the user. Also, it has been shown that... 

    Measuring Concentration of Heavy Metals in Waste Water Using Biosensor

    , M.Sc. Thesis Sharif University of Technology Heydarian Dolatabadi, Ehsan (Author) ; Alemzadeh, Iran (Supervisor) ; Kalantarian, Asadollah (Supervisor)
    Abstract
    Wastewater, especially with heavy metal contamination, is a global environmental concern. Numerous techniques have been tested for online controlling and monitoring the concentration of heavy metal ions; yet, there are many challenges in performing these techniques. Biosensor is cheap, easily available, simple, fast, selective, sensitive, and repeatable so it is an excellent alternative for the detection and quantification of hazardous particles in the wastewater. In this study, a Nano biosensor with high detection of copper ions has been fabricated. PEDOT:PSS as a highly conductive polymer is coupled with gold nanoparticles to modify the surface of graphite electrode and results in higher... 

    Investigation of the Optimum Conditions for the Regeneration of Anion and Cation Exchange Resins of the TR System of Bushehr Nuclear Power Plant

    , M.Sc. Thesis Sharif University of Technology Arkannia, Mohammad Hossein (Author) ; Outokesh, Mohammad (Supervisor) ; Seyed Kalal, Hossein (Supervisor) ; Habibian, Alireza (Co-Supervisor)
    Abstract
    The main purpose of this research is to select a suitable solution for regeneration of ion exchange resins of TR system of Bushehr nuclear power plant and also to compare and evaluate the possibility of using industrial cationic resin (Amberlite IR120) instead of nuclear grade cationic resin (Amberlite IRN97).First, different solutions for regeneration of cationic resins were investigated. For this purpose, three strong acids including hydrochloric acid (HCl), sulfuric acid (H2SO4) and nitric acid (HNO3) were selected and each of these acids was tested in two different concentrations and two different linear velocities; Also, to evaluate the appropriate solution for anionic resin... 

    Synthesis and Characterization of CuO Microflowers/Ppy Nanowires NCs as Anode Materials for Lithium-ion Battery

    , M.Sc. Thesis Sharif University of Technology Helli, Motahareh (Author) ; Sadrnezhad, Khatiboleslam (Supervisor)
    Abstract
    Novel Copper Oxide microflowers /Polypyrroles nanowire nanocomposites with various wight ratio have been synthesized.The synthesized CuO/Ppy NCs and Cuo microflowers are characterized by XRD, FT-IR, TGA, FESEM and EDX line analysis/elemntal mapping. The formation mechanism of CuO microflower and Ppy nanowires are also well explained.All syntesized samples have been used as as anode material for li-ion batteries in order to measure their electochemical lithium-ion storage properties. It is demonstrated that presence of Ppy nanowire with different weight ratio plays important role in lithium-storage properties of the hybrid CuO/Ppy NCs. With increase in the mass ratio of Ppy nanowire cyclic... 

    Design of an Observer for Lithium-ion Battery State of Charge

    , M.Sc. Thesis Sharif University of Technology Fereydooni Sefid Dashti, Alireza (Author) ; Pishvaie, Mahmoud Reza (Supervisor) ; Vafa, Ehsan (Supervisor)
    Abstract
    To ensure stable and optimal operation of lithium-ion batteries (LIBs), it is necessary to use a management system for online monitoring and accurate estimation of battery State of Charge (SOC). Due to LIBs' complex dynamics and effective factors such as temperature and side reactions, battery SOC estimation has become one of the greatest challenges for experts in the field. In this research, an adaptive sliding mode observer has been designed and evaluated for a cylindrical lithium manganese oxide battery with a capacity of 1258 mAh. At first, rigorous simulation of lithium-ion battery has been performed by utilizing the P2D electrochemical as well as thermal and aging model to be the main... 

    Design and Construction of a Sputter Ion Pump

    , M.Sc. Thesis Sharif University of Technology Bazrafshan, Gholamreza (Author) ; Vosoughi, Naser (Supervisor) ; Rahighi, Javad (Supervisor)
    Abstract
    Design and construction process of special kind of sputter ion pump is described briefly in this paper. In order to investigate the optimization of effective parameters in choosing and designing ILSF ion pumps, this pump has been designed and manufactured. By optimizing some parameters such as dimension and shape of penning cells, anode voltage, magnetic field and internal structure of pump, it is possible to significantly decrease the cost of construction and operation of synchrotron vacuum system. By using the results of simulations and calculations of electromagnetic field, plasma simulation or glow discharge, titanium sputtering, etc., critical parameters in design of internal structure... 

    Converting the Organic Constituents of the Li-ion Batteries to Added-value Species with the Possibility of Removing the Environmental Pollutants

    , M.Sc. Thesis Sharif University of Technology Moosavi Shahabi, Mohamad Ali (Author) ; Fotovat, Farzam (Supervisor)
    Abstract
    During the last few years, the number of electric devices using lithium-ion batteries as a source of energy has increased drastically. The lifespan of these batteries is very short (2-3 years) and according to the statistics only 25% of which is recycled. However, considering the variety of materials used in these batteries, recycling them can be highly gainful. One of the technical challenges in the way of recycling Li-ion batteries is the presence of polyvinylidene fluoride (PVDF), that besides raising issues during recycling processes causes the production of toxic fluorine or hydrogen fluoride effluents. The second issue is the presence of metals with high oxidation states in these... 

    Lithium Adsorption on TiO2 Ion-sieve from Magnesium Treated Brine Sources

    , M.Sc. Thesis Sharif University of Technology Naji Toosi, Alireza (Author) ; Asgari, Masoud (Supervisor)
    Abstract
    Brines are one of the main resources for lithium extraction and Iran has got many high magnesium and low lithium brine resources. In order to extract lithium, it is required to carefully identify these resources and their associated compounds and then an appropriate method can be adopted to extract lithium. Among the Previous researches, Bahadori, Jandaghi and Moazeni developed methods for removal of undesirable brines elements, Deposition of lithium from refined brine and lithium adsorption anatase ion-sieves membrane respectively; in this study it has been tried to investigate the optimization of the adsorption process, onto the TiO2-B ion sieve with nanotube morphology. TiO2-B nanotubes... 

    The Effect of Pomegranate Peel Extract as a Green Anti-corrosion Agent and Aluminium Oxide Nanostructured Containing Sulfur on the Anticorrosion
    Performance of Epoxy Coating

    , M.Sc. Thesis Sharif University of Technology Movahedzadeh, Zahra (Author) ; Ramazani Saadatabadi, Ahmad (Supervisor)
    Abstract
    The present work focuses on the sustainable development of an intelligent self-healing anticorrosion coating using nanocontainers based on the aluminium oxide nanostructure-pomegranate peel extract-Ce3+ (Ce-PPE@Cat). The Ce-PPE@Cat nanopigment was introduced into the epoxy film (Ep) to achieve a smart barrier/ self-healing anti-corrosive property. To this end, a couple of characterization tests, including FT-IR, TGA, and, BET have been carried out to investigate the Ce-PPE@Cat nanopigment structure/composition. The effectiveness of the anti-corrosion performance of the established coatings was confirmed by EIS, FE-SEM, and accelerated salt spray test. Furthermore, EIS studies revealed that... 

    Optimization of 18650 Cells Arrangement in Tesla Battery Pack with Active, Passive and Hybrid Cooling Systems

    , M.Sc. Thesis Sharif University of Technology Shamekhi, Alireza (Author) ; Aryanpour, Masoud (Supervisor)
    Abstract
    In this study, three active, passive, and hybrid thermal management systems are applied to a lithium battery module with industrial specifications, i.e., Tesla battery module, and the optimal conditions are extracted. The thermal and electrochemical behavior of battery cells is modeled using the quasi-two-dimensional approach by Newman’s method. The effects of inter-cellular distance on the maximum temperature and on the temperature distribution in the pack as the target variables are thoroughly investigated. A suitable range for the above distances is then determined in order to reduce the overall cooling power and the expected thermal performance of the pack. The results of temperature... 

    Chemomechanical Modeling of Silicon Electrode in Lithium-Ion Battery by Considering the Effects of Large Plastic Deformation and Strain Rate

    , Ph.D. Dissertation Sharif University of Technology Bagheri, Afsar (Author) ; Naghdabadi, Reza (Supervisor) ; Argavani Hadi, Jamal (Supervisor)
    Abstract
    In Li-ion batteries, large volume changes of electrodes with high capacity, such as silicon electrodes during charging and discharging processes (insertion/extraction of lithium into/from the electrode), lead to restrictions on the use of this type of electrode. Given the very high capacity of silicon, predicting and modeling the behavior of silicon electrodes during electrochemical cycles is important and is also addressed in this thesis. First, using the theory of linear elasticity, relations are proposed that couple the diffusion of particles with small elastic deformation. The effect of hydrostatic stress on diffusion and stresses is investigated in lithiation processes. Then, the...