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    (Experimental Investigation Influence of Submerged Vanes on Dimension Separation Zone and Control Turbulent at a 90˚ Open-Channel Junction)

    , M.Sc. Thesis Sharif University of Technology Nikbin, Sahar (Author) ; Borghei, Mahmoud (Supervisor)
    Abstract
    In this study, the effect of submerged vanes on the flow pattern and dimensions of separation zone at a 90˚ open-channel Junction were investigated. The experiments were conducted in three stages. First, for validity of data with the results of webber et al, using ADV, velocities was teken without submerged vanes.in the second stage, experiments with dye injection was performed at confluence for several initial arrangement of vanes. From 54 different arrangements, two arrangements were selected. In three stage, three dimensional velocities was teken in two arrangement selected. Due to the significant reduction the size of separation zone in one of these arrangements, with moving this... 

    Efficient In-network Caching in Content-centric Networks

    , M.Sc. Thesis Sharif University of Technology Nikbin, Behzad (Author) ; Movaghar, Ali (Supervisor)
    Abstract
    Content-Centric Network is a new network paradigm. In this paradigm, contents are the main element of the network, and the place holding the content is transparent to users. In other words, the concept of content’s place is eliminated. In spite of other common paradigms in which caching operation is occurred in just a few predefined nodes and also it is limited to a specific application, in this kind of network, caching operation can be occurred in all nodes, independent of the application. Furthermore, due to elimination of the concept of the content’s place, matching of same contents held in different places can be possible. So caching in such networks became an important issue. In caching... 

    Design and Synthesis of a Drug Delivery System Based on Mesoporous Bioactive Glass

    , M.Sc. Thesis Sharif University of Technology Mirsafaie, Sahar Sadat (Author) ; Abdekhodaie, Mohammad Jafar (Supervisor)
    Abstract
    The aim of this research is to develop a smart mesoporous bioactive glass-based carrier for targeted drug delivery to cancer cells, particularly bone cancer cells. To achieve this, mesoporous bioactive glass nanoparticles were first synthesized, followed by surface modification with amine groups. To prevent premature drug release before reaching the target tissue and to introduce pH sensitivity, the nanoparticle pores were coated with oxidized hyaluronic acid via Schiff-base bonding with the amine groups on the surface. The use of hyaluronic acid facilitates active targeting of CD44 receptors, which are overexpressed on the surface of cancer cells compared to healthy cells. This process... 

    Electrodeposition of Pt nanostructures and its Application as Glucose Sensor

    , Ph.D. Dissertation Sharif University of Technology Mahshid, Sahar Sadat (Author) ; Dolati, Abolghasem (Supervisor) ; Ghorbani, Mohammad (Supervisor)
    Abstract
    The present work describes sensing application of modified Pt nanostructures towards detection of glucose. Modified Pt nanostructured electrodes were prepared using electrodeposition method such as chronoampermetry and potentiostatic pulse methods. The electrodeposition of Pt nanostructures was first studied by voltammetry and amperommetry techniques and then potentiostatic pulse method has been used to produce the alloyed structures of platinum. In this regard, the first electrode was proposed based on alloyed Pt/Ni nanowire arrays (NWAs) for the non-enzymatic detection of glucose. The Pt/Ni NWAs were prepared by pulse electrodeposition of Pt and Ni within a nano-pore polycarbonate (PC)... 

    Quantum Estimation of Open Systems Using Extended Cramer-Rao Bounds

    , M.Sc. Thesis Sharif University of Technology Mehboudi, Mohammad (Author) ; Rezakhani, Ali (Supervisor) ; Alipour, Sahar (Co-Advisor)
    Abstract
    Any physical system is characterized with some set of quantities or parameters, knowing which, is equivalent to estimation of the system. Evaluating such parameters is usually done using tomography methods. An important question to ask, is how to increase the precision of measurement, being able to do some specific set of physical operations, say, measurement?
    this question is more important in parameter estimation in quantum meanical systems. It has been shown that, quantum meanics causes a fundamental limit, on precision of estimating su parameters, escribed by the so called “antum Cramér-Rao bound”.We must note that almost all quantum meanical systems are interacting with the... 

    Pore-Scale Investigation of the Effect of Fracture and Mineralogy on Formation Damage Caused by Drilling Fluid

    , M.Sc. Thesis Sharif University of Technology Nikbin, Hadi (Author) ; 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... 

    Molecular dynamics simulation of the dissociation mechanism of P-selectin from PSGL-1

    , Article Journal of Theoretical and Computational Chemistry ; Volume 16, Issue 4 , 2017 ; 02196336 (ISSN) Hassani Ardekani, H ; Niroomand Oscuii, H ; Nikbin, E ; Shamloo, A ; Sharif University of Technology
    World Scientific Publishing Co. Pte Ltd  2017
    Abstract
    Interactions between P-selectin, expressed on activated endothelium, and its counterpart P-selectin glycoprotein ligand-1 (PSGL-1), expressed on leukocytes, play a pivotal role in adhesive events that recruit circulating leukocytes toward inflamed or injured tissues. Atomistic understanding of the association and dissociation of these bonds under blood flow is necessary to define the underlying mechanism. In this study, steered molecular dynamics (SMD) simulations were applied to investigate the conformational changes of P-LE/SGP-3 construct (an effective binding unit of the P-selectin/PSGL-1 complex) under stretching with constant velocity. In the present simulations, a self-built force... 

    Coarse Grained Modeling of F-BAR Protein Interaction with Lipid Membrane

    , M.Sc. Thesis Sharif University of Technology Nikbin, Ehsan (Author) ; Ejtehadi, Mohammad Reza (Supervisor) ; Seyyed Reihani, Nader (Supervisor)
    Abstract
    F-BAR protein is one of the Bin/Amphiphysin/Rvs (BAR) superfamily proteins which contributes in curvature generation and stabilization of lipid membranes. These proteins usualy form lattices on the membrane and can sculpt the membrane. In this project the interaction of F-BAR protein with a lipid membrane is modeled using coarse grained molecular dynamics approach. In order to describe the curvature generation and stabilization we would need an appropriate coarse grained model for the lipid membrane. In this project the proposed model for the membrane describes a membrane in liquid phase with a lateral diffusion in the lipid bilayer. Depth and width of the lipids potential is determined in... 

    Selective Transfection of Smart Polymeric Nanoparticles Into Reactive Astrocytes in Animal Model of Spinal Cord Injury

    , Ph.D. Dissertation Sharif University of Technology Sabourian, Parinaz (Author) ; Frounchi, Masoud (Supervisor) ; Mashayekhan, Shohreh (Co-Supervisor) ; Kiani, Sahar (Co-Supervisor)
    Abstract
    In this study, chitosan-based nanoparticles were prepared due to their biocompatibility, availability, high loading capacity of drug, stimulus responsive behavior and the presence of active functional groups. Chitosan was chemically functionalized with reactive oxygen species (ROS)-responsive moiety to respond to the oxidative stess and endosomal pH in nerve injuries. To prepare nanoparticles, functinalized chitosan ionically gelated with pH-responsive polyanions with ROS-scavenging properties such as polyacrylic acid and hyaluronic acid. Then, pH- and ROS-responsive nanoparticles were used for selective transfection into reactive astrocytes and axonal regeneration in spinal cord injuries.... 

    The effect of aging on the fracture characteristics and ductility of self-compacting concrete

    , Article Materials and Design ; Volume 55 , March 2014 , Pages 937-948 Beygi, M. H. A ; Kazemi, M. T ; Nikbin, I. M ; Vaseghi Amiri, J ; Sharif University of Technology
    March 2014
    Abstract
    Good knowledge of fracture parameters and cracking behavior of self-compacting concrete (SCC) from early ages until the SCC becomes mature plays an important role in design of SCC structure and also in evaluation of durability and consequently prevention of damage. In this paper, variation of fracture parameters and corresponding ductility behavior of SCC at different ages (e.g. 3days, 7days, 28days and 90days) for SCC mixes with w/c ratios of 0.45 and 0.65 have been experimentally studied. To do so, three-point bending tests were carried out on 120 notched beams. Then, size effect method (SEM) and work of fracture method (WFM) were applied to interpret the results. The results of analyses... 

    The effect of water to cement ratio on fracture parameters and brittleness of self-compacting concrete

    , Article Materials and Design ; Volume 50 , 2013 , Pages 267-276 ; 02613069 (ISSN) Beygi, M. H. A ; Kazemi, M. T ; Nikbin, I. M ; Amiri, J. V ; Sharif University of Technology
    Elsevier Ltd  2013
    Abstract
    The paper describes an experimental research on fracture characteristics of self-compacting concrete (SCC). Three point bending tests conducted on 154 notched beams with different water to cement (w/c) ratios. The specimens were made from mixes with various w/c ratios from 0.7 to 0.35. For all mixes, common fracture parameters were determined using two different methods, the work-of-fracture method (WFM) and the size effect method (SEM). Test results showed that with decrease of w/c ratio from 0.7 to 0.35 in SCC: (a) the fracture toughness increases linearly: (b) the brittleness number is approximately doubled: (c) the effective size of the process zone cf in SEM and the characteristic... 

    Nanogold imprinted starch bionanocomposites for food packaging applications

    , Article Starch Based Nanomaterials for Food Packaging: Perspectives and Future Prospectus ; 2023 , Pages 209-226 ; 978-044318967-8 (ISBN); 978-044318968-5 (ISBN) Tariq, T ; Saleem, I. M ; Sahar, A ; Raza, N ; Sameen, A ; Nayik, G. A ; Ramniwas, S ; Sharif University of Technology
    Elsevier  2023
    Abstract
    Food science researchers are concerned about global food wastage due to decreased shelf life. It has been shown that using approaches based on nanotechnology, including metal-based nanoparticles (NPs), can alleviate the issues with decreased shelf life and environmental problems. Gold nanoparticles (AuNPs) and their synthesis have seen notable advancements in the last several decades. AuNPs are now utilised more often in industrial and medicinal settings. AuNPs are being employed in the nanopackaging industry as a recently adopted technique because of their medicinal and antibacterial properties and their inert and hypoallergenic nature. When employed in the food industry, AuNPs have... 

    Evaluation of the effect of maximum aggregate size on fracture behavior of self compacting concrete

    , Article Construction and Building Materials ; Vol. 55 , 2014 , pp. 202-211 ; ISSN: 09500618 Beygi, M. H. A ; Kazemi, M. T ; Vaseghi Amiri, J ; Nikbin, I. M ; Rabbanifar, S ; Rahmani, E ; Sharif University of Technology
    2014
    Abstract
    This paper presents and discusses the effect of maximum size of coarse aggregate on fracture characteristics and brittleness of self-compacting concrete (SCC). Based on an experimental program, a series of three point bending tests were carried out on 86 notched beams, as recommended by RILEM. For all mixes, the parameters were analyzed by the work-of-fracture method (WFM) and by the size effect method (SEM) and consequently a correlation between these methods was obtained which is used to calibrate cracking numerical models. Test results showed that with increase of size of coarse aggregate, (a): fracture energies of GF in WFM and Gf in SEM increase which may be explained by the change in... 

    A comprehensive investigation into the effect of water to cement ratio and powder content on mechanical properties of self-compacting concrete

    , Article Construction and Building Materials ; Vol. 57 , April , 2014 , pp. 69-80 ; ISSN: 09500618 Nikbin, I. M ; Beygi, M. H. A ; Kazemi, M. T ; Vaseghi Amiri, J ; Rabbanifar, S ; Rahmani, E ; Rahimi, S ; Sharif University of Technology
    2014
    Abstract
    Self compacting concrete (SCC), as an innovative construction material in concrete industry, offers a safer and more productive construction process due to favorable rheological performance which is caused by SCC's different mixture composition. This difference may have remarkable influence on the mechanical behavior of SCC as compared to normal vibrated concrete (NVC) in hardened state. Therefore, it is vital to know whether the use of all assumptions and relations that have been formulated for NVC in current design codes are also valid for SCC. Furthermore, this study presents an extensive evaluation and comparison between mechanical properties of SCC using current international codes and... 

    A comprehensive investigation into the effect of aging and coarse aggregate size and volume on mechanical properties of self-compacting concrete

    , Article Materials and Design ; Vol. 59, issue , 2014 , pp. 199-210 ; ISSN: 10263098 Nikbin, I. M ; Beygi, M. H. A ; Kazemi, M. T ; Vaseghi Amiri, J ; Rahmani, E ; Rabbanifar, S ; Eslami, M ; Sharif University of Technology
    2014
    Abstract
    The popularity of self-compacting concrete (SCC), as an innovative construction materials in concrete industry, has increased all over the world in recent decades. SCC offers a safer construction process and durable concrete structure due to its typical fresh concrete behavior which is achieved by SCC's significantly different mixture composition. This modification of mix composition may have significant effect on the hardened mechanical properties of SCC as compared to normal vibrated concrete (NVC). Therefore, it is necessary to know whether the use of all rules and relations that have been formulated for NVC in current design codes based on years of experience are also valid for SCC.... 

    Effect of coarse aggregate volume on fracture behavior of self compacting concrete

    , Article Construction and Building Materials ; Volume 52 , 15 February , 2014 , Pages 137-145 ; ISSN: 09500618 Nikbin, I. M ; Beygi, M. H. A ; Kazemi, M. T ; Vaseghi Amiri, J ; Rahmani, E ; Rabbanifar, S ; Eslami, M ; Sharif University of Technology
    2014
    Abstract
    This paper presents the effect of volume of coarse aggregate on fracture characteristics of self- compacting concrete (SCC). Based on an experimental programme, a series of three point bending tests were carried out on 58 notched beams. SCC was prepared with coarse aggregate in varying percentages of 30%, 40%, 50% and 60% (as the percentage of the total aggregate volume). For all mixes, the fracture parameters were analyzed by the work-of- fracture method (WFM) and by the size effect method (SEM) to obtain a suitable correlation between these methods which is used to calibrate fracture numerical models. The results showed that with decrease of volume of coarse aggregate from 60% to 30% in...