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    Uranium Recovery from Liquid Waste of UCF by Solvent Extraction Method

    , M.Sc. Thesis Sharif University of Technology Aminoro-a-yaei Yamini, Leyla (Author) ; Samadfam, Mohammad (Supervisor) ; Taghizadeh, Mohammad (Supervisor) ; Ghasemi, Mohamad Reza (Co-Advisor)
    The Atomic Energy Organization of Iran (AEOI) has launched a program of low level waste management. This program also includes waste produced at Uranium Conversion Facility (UCF) of Esfahan. The liquid waste, which was generated during the operation of plant and concentrated in lagoon, was characterized for the development of the treatment process. The aim of this study was to recovery of uranium content of liquid waste in the lagoon. The recovery of uranium has the advantage of saving this valuable metal and the avoidance of unacceptable discarding solution to the environment. Uranium may be recovered from an aqueous solution by precipitation, solvent extraction and ion exchange.... 

    Application of Multiscale methods for Modeling Spatial Heterogeneity in Complex Reservoirs

    , M.Sc. Thesis Sharif University of Technology Hajizadeh Mobaraki, Alireza (Author) ; Farhadpour, Farhad A (Supervisor) ; Sayf Kordi, Ali Akbar (Supervisor)
    Underground reservoirs are highly complicated due to the presence of spatial heterogeneities at length scales that span from micrometer in pore structure of the rocks to kilometer in the reservoir models. While large-scale flow units need to be characterized using seismic and well data, detailed displacements of fluids in pore space need to be modeled using thin section analysis and pore network modeling. It is therefore necessary to adopt a multi-scale approach to reservoir description to make best use of all the available data that vary over several orders of magnitude, from micro-scale in pore structure to field scale in reservoir flow models. In this thesis, an integrated framework for... 

    Spectrophotometric Determination of Ametryn Herbicide in Drainage Water Based on Aggregation of Gold Nanoparticles Capped with Citrate

    , M.Sc. Thesis Sharif University of Technology Rastgar, Mortaza (Author) ; Hormozi-Nezhad, Mohammad Reza (Supervisor) ; Torkian, A (Supervisor)
    Due to vast use of Ametryn herbicide in agricultural and even non-agricultural activities and the possibility of contamination of carp and natural water sources by this herbicide, determination of this herbicide in surface and ground water sources is very important. Therefor introducing simple and sensitive method for determination of Ametryn is critical.
    This study demonstrate a simple and sensitive colorimetric method for the detection and determination of Ametryn based on aggregation of citrate capped AuNPs. Studied method relies upon shape and distance dependent AuNPs surface plasmon resonance. By replacing the sulfide containing Ametryn herbicide with citrate molecules on AuNPs... 

    Jahn-Teller Effect in Diamond Vacancy Under Stress

    , M.Sc. Thesis Sharif University of Technology monfared, Mohammad (Author) ; Vesaghi, M. A (Supervisor) ; Babamoradi, M (Co-Advisor)
    Electron states of diamond vacancy under stress were studied theoretically. The generalized Hubbard model is used to calculate the electrons energy levels. The results shows that the degeneracy of some levels (T, with triple space degeneracy) reduced to levels with lower degeneracy (E, with double space degeneracy and A, without degeneracy). Besides this spiting of degeneracy the energy of all states changed and therefore the transition energy between these states changed too. Jahn-Teller effect was observed  

    Trajectory Optimization of a Dual-arm Cam-lock Robot Considering Redundancy

    , M.Sc. Thesis Sharif University of Technology Rashidnejhad, Sajad (Author) ; Meghdari, A. (Ali) (Supervisor) ; Ghaemi Osgouie, Kambiz (Supervisor)
    In the present work, trajectory optimization of the Dual-Arm Cam-Lock robot considering kinematic and dynamic redundancy is performed. First, the optimal control problem is solved only considering kinematic redundancy and then is solved considering dynamic redundancy. General form of the dynamic model for the system is developed using Lagrangian relations. Global optimization method is used for redundancy resolution problem. A performance index is defined based on the consumed kinetic energy and is minimized through a desired trajectory using the global optimization method. Formulations of optimal control problem are derived and initial boundary problem is changed to two point boundary value... 

    Design, Simulation and Fabrication of a Centrifugal Microfluidic Device for Circulating Tumor Cells Separation

    , M.Sc. Thesis Sharif University of Technology Naghdloo, Amin (Author) ; Shamloo, Amir (Supervisor) ; Nouri Borujerdi, Ali (Supervisor)
    In this project, two centrifugal microfluidic platforms with the goal of separation and genetical study of circulating tumor cells have been designed, simulated and fabricated. Circulating tumor cells are the ones that are detached from the cancer tumors, entered the blood and disseminated the danger of cancer through other parts of the body. Both passive and active methods of separation are investigated in this study. The passive method is based on the inertial effects of the fluid and the active method is based on the magnetophoretic force exerted from an external magnetic field. In order to use the active method, the magnetic nanoparticles are attached to the breast cancer cells by the... 

    Real-Time Fusion of Asynchronous Data in Distributed Sensor Networks

    , Ph.D. Dissertation Sharif University of Technology Talebi, Hadi (Author) ; Hemmatyar, A. M. Afshin (Supervisor)
    Real-time asynchronous data fusion for high-speed phenomena is an important and challenging task in the sensor networks. Examples of data fusion applications in sensor networks are: managing the traffic of maneuvering airplanes and ground vehicles in airside areas of an airport, traffic management in streets and roads, Driver Assistance Systems, guidance of antiaircraft and antimissile missiles. In all the data fusion applications the estimation of the required variables is necessary.
    In this research two methods are introduced for real-time asynchronous data fusion, especially for track-to-track fusion of high-speed phenomena in sensor networks. The effectiveness and usability of these... 

    Phase diagram of J1-J2 transverse field Ising model on the checkerboard lattice: a plaquette-operator approach

    , Article European Physical Journal B ; Volume 88, Issue 10 , October , 2015 ; 14346028 (ISSN) Sadrzadeh, M ; Langari, A ; Sharif University of Technology
    springer berlin  2015
    We study the effect of quantum fluctuations by means of a transverse magnetic field (Γ) on the antiferromagnetic J1-J2 Ising model on the checkerboard lattice, the two dimensional version of the pyrochlore lattice. The zero-temperature phase diagram of the model has been obtained by employing a plaquette operator approach (POA). The plaquette operator formalism bosonizes the model, in which a single boson is associated to each eigenstate of a plaquette and the inter-plaquette interactions define an effective Hamiltonian. The excitations of a plaquette would represent an-harmonic fluctuations of the model, which lead not only to lower the excitation energy compared with a single-spin flip but... 

    The importance of electron correlation in graphene and hydrogenated graphene

    , Article European Physical Journal B ; Volume 88, Issue 10 , October , 2015 ; 14346028 (ISSN) Hadipour, H ; Jafari, S. A ; Sharif University of Technology
    springer berlin  2015
    Local density approximation (LDA) and Green function effective Coulomb (GW) calculations are performed to investigate the effect of electronic correlations on the electronic properties of both graphene and graphane. The size of band gap in graphane increases from 3.7 eV in LDA to 4.9 eV in GW approximation. By calculating maximally localized Wannier wave functions, we evaluate the necessary integrals to get the Hubbard U and the exchange J interaction from first principles for both graphene and graphane. Our ab-initio estimates indicate that in the case of graphene, in addition to the hopping amplitude t ∼ 2.8 eV giving rise to the Dirac nature of low lying excitations, the Hubbard U value... 

    Investigation of cervical spine curvature in females with postural neck pain

    , Article Journal of Zanjan University of Medical Sciences and Health Services ; Volume 25, Issue 110 , 2017 , Pages 110-119 ; 16069366 (ISSN) Salahzadeh, Z ; Maroufi, N ; Ahmadi, A ; Behtash, H ; Hazhir Sahneh, S ; Parnianpour, M ; Sharif University of Technology
    Zanjan University of Medical Sciences and Health Services  2017
    Background and Objective: Changes in the cervical spine curvature leads to increased shear force and compression stress on cervical spine and axial loading in different cervical segments. The objective of this study was to compare the general and segmental curvature in the upper and lower cervical spine of women with postural neck pain and Forward Head Posture (FHP), women without neck pain but with FHP and healthy women. Material and Methods: 45 women were divided into three groups: 15 women with postural neck pain and FHP, 15 women without neck pain but with FHP and 15 healthy women. Photography was used to assess neck posture while cervical spine curvature was measured using fluoroscopy... 

    Evaluation of the effects of fullerene c60 nanoparticles on oxidative stress parameters in normal rats liver and brain

    , Article Journal of Advances in Medical and Biomedical Research ; Volume 27, Issue 124 , 2019 , Pages 8-15 ; 26766264 (ISSN) Namadr, F ; Bahrami, F ; Bahri, Z ; Ghanbari, B ; Elahi, S. A ; Mohammadi, M. T ; Sharif University of Technology
    Zanjan University of Medical Sciences and Health Services  2019
    Background & Objective: The potent antioxidant property of fullerene C60 nanoparticles and their derivatives has been demonstrated in a wide range of in vitro and in vivo studies. Hence, we examined the effects of fullerene C60 on the oxidative stress parameters in brain and liver of the rats in normal situation. Materials & Methods: The study was performed in two groups of Wistar rats (each group, n = 6); normal and fullerene-treated normal animals. Treated rats received fullerene via oral gavage at dose of 1 mg/kg/day for 60 days. At termination of the study, the oxidative stress parameters were determined in brain and liver tissues, including the contents of glutathione (GSH) and... 

    Thermoeconomic analysis and multi-objective optimization of an integrated solar system for hydrogen production using particle swarm optimization algorithm

    , Article Journal of Thermal Engineering ; Volume 7, Issue 4 , 2021 , Pages 746-760 ; 21487847 (ISSN) Keykhah, S ; Assareh, E ; Moltames, R ; Taghipour, A ; Barati, H ; Sharif University of Technology
    Yildiz Technical University  2021
    This study aims to investigate the hydrogen production process using an integrated system based on solar energy. This system includes an evacuated tube collector to absorb solar energy as input energy of the system. A parametric analysis was conducted to determine the most important design parameters and evaluate these parameters' impact on the system's objective functions. For identifying the optimum system conditions, multi-objective optimization was performed using particle swarm optimization (PSO) algorithm. The results obtained from the parametric analysis show that an increment in the collector mass flow rate and the turbine inlet temperature, as well as a decrement in the collector... 

    Thermoeconomic analysis and multi-objective optimization of a novel trigeneration system consisting of kalina and humidificationdehumidification desalination cycles

    , Article Journal of Thermal Engineering ; Volume 8, Issue 1 , 2022 , Pages 52-66 ; 21487847 (ISSN) Behnam, P ; Faegh, M ; Fakhari, I ; Ahmadi, P ; Faegh, E ; Rosen, M. A ; Sharif University of Technology
    Yildiz Technical University  2022
    Low-temperature geothermal heat sources have the highest share of geothermal energy in the world. Utilization of these heat sources for energy and freshwater generation can play an important role in meeting energy and freshwater demands. To do so, this study aims to propose a novel trigeneration cycle powered by low-temperature geothermal sources. The proposed system, which is an integration of Kalina and humidification-dehumidification (HDH) cycles, is used for the generation of electricity, heating, and freshwater. For the Kalina cycle, an evaporative condenser is used. It also acts as a humidifier and heater of the humidification-dehumidification desalination cycle, resulting in a... 

    Kinetics of swelling of cylindrical temperature-responsive hydrogel: a semi-analytical study

    , Article International Journal of Applied Mechanics ; Volume 12, Issue 8 , 2020 Namdar, A. H ; Mazaheri, H ; Sharif University of Technology
    World Scientific  2020
    Cylindrical hydrogels have a wide variety of applications, especially in microfluidics as micro-valves, micro-mixers, and micro-lenses. Main advantages of them can be mentioned as their simple geometry and autonomous functionality due to their responses to the environmental stimuli. In current research, kinetics of swelling, shrinking and force generation of cylindrical temperature-responsive hydrogels have been investigated analytically. According to this, models of fluid permeation and large deformation of the hydrogels were considered and an analytical solution was performed. In order to study the behavior of the cylindrical hydrogels, the temperature is changed between higher and lower... 

    Parametric study of droplet formation and characteristics within microfluidic devices - A case study

    , Article International Journal of Applied Mechanics ; Volume 12, Issue 7 , 2020 Salehi, S. S ; Shamloo, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
    World Scientific  2020
    Droplet-based microfluidics technologies hold great attention in a wide range of applications, including chemical analysis, drug screening, and food industries. This work aimed to describe the effects of different physical properties of the two immiscible phases on droplet formation in a flow-focusing microfluidic device and determining proper flow rates to form a droplet within the desired size range. A numerical model was developed to solve the governing equations of two-phase flow and the results were validated with previous experimental results. The results demonstrate different types of droplet formation regimes from dripping to jetting and different production rates of droplets as a... 

    Characterization of magnetized CNT-based hybrid nanofluid subjected to convective phenomenon

    , Article International Journal of Modern Physics B ; Volume 35, Issue 28 , 2021 ; 02179792 (ISSN) Hayat, T ; Khan, W. A ; Aqsa ; Waqas, M ; Abbas, S. Z ; Malik, M. Y ; Alqahtani, A. S ; Sharif University of Technology
    World Scientific  2021
    Hybrid nanofluid gains attention of scientists due to its dynamic properties in various fields, and thus, hybrid nanofluids can be taken as an innovative form of nanofluids. Even though analysts acquire tremendous results in the field of hybrid nanofluids but yet no study has been carried out to predict magnetohydrodynamic effects in such fluid models. In this present analysis, influence of MHD has been investigated for the micro hybrid nanofluid over a stretched surface under convective conditions. Combine boundary layer equations for the flow have been altered into a suitable form via boundary layer approximations. Further, complete nonlinear system of equations has been numerically solved... 

    Automated analysis of karyotype images

    , Article Journal of Bioinformatics and Computational Biology ; Volume 20, Issue 3 , 2022 ; 02197200 (ISSN) Khazaei, E ; Emrany, A ; Tavassolipour, M ; Mahjoubi, F ; Ebrahimi, A ; Motahari, S. A ; Sharif University of Technology
    World Scientific  2022
    Karyotype is a genetic test that is used for detection of chromosomal defects. In a karyotype test, an image is captured from chromosomes during the cell division. The captured images are then analyzed by cytogeneticists in order to detect possible chromosomal defects. In this paper, we have proposed an automated pipeline for analysis of karyotype images. There are three main steps for karyotype image analysis: image enhancement, image segmentation and chromosome classification. In this paper, we have proposed a novel chromosome segmentation algorithm to decompose overlapped chromosomes. We have also proposed a CNN-based classifier which outperforms all the existing classifiers. Our... 

    The novel soliton solutions for the conformable perturbed nonlinear Schrödinger equation

    , Article Modern Physics Letters B ; Volume 36, Issue 8 , 2022 ; 02179849 (ISSN) Yépez-Martínez, H ; Pashrashid, A ; Gómez Aguilar, J. F ; Akinyemi, L ; Rezazadeh, H ; Sharif University of Technology
    World Scientific  2022
    The sub-equation method is implemented to construct exact solutions for the conformable perturbed nonlinear Schrödinger equation. In this paper, we consider three different types of nonlinear perturbations: The quadratic-cubic law, the quadratic-quartic-quintic law, and the cubic-quintic-septic law. The properties of the conformable derivative are discussed and applied with the help of a suitable wave transform that converts the governing model to a nonlinear ordinary differential equation. Furthermore, the order of the expected polynomial-type solution is obtained using the homogeneous balancing approach. Dark and singular soliton solutions are derived. © 2022 World Scientific Publishing... 

    Nonlinear free vibration analysis of in-plane Bi-directional functionally graded plate with porosities resting on elastic foundations

    , Article International Journal of Applied Mechanics ; Volume 14, Issue 1 , 2022 ; 17588251 (ISSN) Hashemi, S ; Shahri, P. K ; Beigzadeh, S ; Zamani, F ; Eratbeni, M. G ; Mahdavi, M ; Heidari, A ; Khaledi, H ; Abadi, M. R. R ; Sharif University of Technology
    World Scientific  2022
    This paper deals with the nonlinear free vibration analysis of in-plane bi-directional functionally graded (IBFG) rectangular plate with porosities which are resting on Winkler-Pasternak elastic foundations. The material properties of the IBFG plate are assumed to be graded along the length and width of the plate according to the power-law distribution, as well as, even and uneven types are taken into account for porosity distributions. Equations of motion are developed by means of Hamilton's principle and von Karman nonlinearity strain-displacement relations based on classical plate theory (CPT). Afterward, the time-dependent nonlinear equations are derived by applying the Galerkin... 

    Dynamic feedback stabilization of timoshenko beam with internal input delays

    , Article WSEAS Transactions on Mathematics ; Volume 17 , 2018 , Pages 101-112 ; 11092769 (ISSN) Genqi, X ; Jalili Rahmati, A ; Badpar, F ; Sharif University of Technology
    World Scientific and Engineering Academy and Society  2018
    In this paper, we consider the exponential stabilization problem of a Timoshenko beam with interior local controls with input delays. In the past, most of the stabilization results for the Timoshenko beam were on the boundary control with input delays. In the present paper we shall extend the method treating the boundary control with delays to the case of interior local control with delays. Essentially we design a new dynamic feedback control laws that stabilizes exponentially the system. Detail of the design procedure of the dynamic feedback controller and analysis of the exponential stability are given. © 2018 World Scientific and Engineering Academy and Society. All Rights Reserved