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Comparison of logarithmic, elliptic, and conical helical spiral for isolation of circulating tumor cells based on inertial method
, Article Physics of Fluids ; Volume 34, Issue 9 , 2022 ; 10706631 (ISSN) ; Mozhdehbakhsh Mofrad, Y ; Safari, M ; Naseri, T ; Sharif University of Technology
American Institute of Physics Inc
2022
Abstract
Cancer is one of the most significant causes of death in the world. It has been shown that the role of circulating tumor cells (CTCs) in the early detection of cancer is crucial. Since the number of these cancerous cells in blood is very rare, the inertial microfluidic devices are one of the best candidates for the isolation of CTCs because they result in a high throughput process. Consequently, they can process a large volume of blood in a short time. Despite extensive computational and experimental studies on inertial microfluidic platforms, the impact of the curvature has not been thoroughly investigated during separation. In this paper, the feasibility of isolation of CTCs for...
PH-Sensitive polydopamine–La (III) complex decorated on carbon nanofiber toward on-demand release functioning of epoxy anti-corrosion coating
, Article Langmuir ; Volume 38, Issue 38 , 2022 , Pages 11707-11723 ; 07437463 (ISSN) ; Saadatabadi, A. R ; Mahdavian, M ; Haddadi, S. A ; Sharif University of Technology
American Chemical Society
2022
Abstract
The high aspect ratio and unique thermal and electrical characteristics of carbon nanofiber (CNF) made it an ideal physical barrier against the penetration of corrosive ions. However, the poor compatibility of the CNF with the polymer matrix and the lack of active corrosion inhibitors are the key limitations of this nanomaterial, resulting in short-term anti-corrosion resistance. An intelligent self-healing epoxy (EP) coating, including CNF modified with a polydopamine (PDA)-La3+ complex, was successfully fabricated to overcome these issues. Electrochemical impedance spectroscopy (EIS) evaluation implied that mild steel (MS) submerged in a 3.5 wt % NaCl solution containing the CNF-PDA-La...
Machine learning-aided scenario-based seismic drift measurement for RC moment frames using visual features of surface damage
, Article Measurement: Journal of the International Measurement Confederation ; Volume 205 , 2022 ; 02632241 (ISSN) ; Mansourdehghan, S ; Asjodi, A. H ; Dolatshahi, K.M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
This paper presents a novel computer vision-based methodology for assessment of the seismic damage in reinforced concrete moment frames using visual characteristics of surface damage following an earthquake. An extensive collected database comprising 974 images associated with 256 cyclic-loaded damaged beam-column joints, providing a set of cracking and crushing progression with increasing the evolution of damage level, is collected and used for the development and validation of the methodology. Employing image processing techniques, the characteristics of the surface damage, including the cracking length and crushing areas, are measured and used in a scenario-based assessment for the...
Mitigating the effect of urban layout on torsion of buildings caused by infill walls
, Article Earthquake and Structures ; Volume 23, Issue 2 , 2022 , Pages 151-168 ; 20927614 (ISSN) ; Tabeshpour, M. R ; Saradj, F. M ; Sharif University of Technology
Techno-Press
2022
Abstract
Torsion is one of the most important causes of building collapse during earthquakes. Sometimes, despite the symmetric form of the building, infill walls disturb the symmetry of the lateral resisting system. The purpose of this research is to investigate the effect of urban layout on developing torsion caused by infill walls. For this purpose, a typological study was conducted based on the conditions of perimeter walls on 364 buildings and then 9 cases were selected. The dimensions of the selected buildings are constant and the conditions of the perimeter walls including facades with openings and cantilevered facades are variable. The selected buildings with 60 different layouts of infill...
Data-driven damage assessment of reinforced concrete shear walls using visual features of damage
, Article Journal of Building Engineering ; Volume 53 , 2022 ; 23527102 (ISSN) ; Dolatshahi, K. M ; Asjodi, A. H ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This paper proposes a damage assessment framework based on the visual features of a damaged reinforced concrete shear wall, such as crack pattern distribution, crushing areal density, aspect ratio, and the presence of the boundary condition. The study contains two parts including: identifying the performance level of the damaged walls (i.e., Immediate Occupancy, Life Safety, and Collapse Prevention) and estimating the residual strength and drift ratio of the walls. The research database contains 236 images of 72 reinforced concrete shear walls tested in the laboratory under the quasi-static cyclic loadings at various drift ratios between 0 and 4%. To identify the performance level of a...
Investigating the behavior of cracks in welded zones of supporting structure of spherical pressure vessel under seismic loading
, Article Journal of Constructional Steel Research ; Volume 191 , 2022 ; 0143974X (ISSN) ; Ghazi, M ; Adibnazari, S ; Rofooei, F. R ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In this paper, the numerical studies on the semi-elliptical crack behavior in different locations of welded zones in the supporting structure of a spherical pressure vessel under an earthquake are presented. The cracks in the welded zones of supporting structures under earthquake effects may jeopardize the safety of spherical pressure vessels and result in catastrophic failure. A detailed finite element sub-modeling technique is carried out to compute the mixed-mode stress intensity factors along the crack front. Furthermore, crack behavior with different aspect ratios a/c: 0.25, 0.5, and 0.75 at the weld and the heat-affected zone of the supporting structure is evaluated. The...
Spatial analysis of damage evolution in cyclic-loaded reinforced concrete shear walls
, Article Journal of Building Engineering ; Volume 49 , 2022 ; 23527102 (ISSN) ; Dolatshahi, K. M ; Ebrahimkhanlou, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This paper introduces a probabilistic framework to quantify the spatial distribution of cracking and crushing in rectangular reinforced concrete shear walls at different drift ratios. In this research, a comprehensive probabilistic spatial analysis is conducted on an extensive collected database of reinforced concrete shear walls tested under the quasi-static cyclic loading. The database includes 235 images of 72 damaged walls with various geometry and material properties at different drift ratios between 0.0 and 4.0%. Various image processing filters are implemented to the images to highlight the wall areas that are more prone to cracking and crushing. Then, advanced statistical analysis is...
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) ; 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
Abstract
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...
Aeroelastic optimization of the high aspect ratio wing with aileron
, Article Computers, Materials and Continua ; Volume 70, Issue 3 , 2022 , Pages 5569-5581 ; 15462218 (ISSN) ; Mahariq, I ; Ghadak, F ; Accouche, O ; Jarad, F ; Sharif University of Technology
Tech Science Press
2022
Abstract
In aircraft wings, aileron mass parameter presents a tremendous effect on the velocity and frequency of the flutter problem. For that purpose, we present the optimization of a composite design wing with an aileron, using machine-learning approach. Mass properties and its distribution have a great influence on the multi-variate optimization procedure, based on speed and frequency of flutter. First, flutter speed was obtained to estimate aileron impact. Additionally mass-equilibrated and other features were investigated. It can deduced that changing the position and mass properties of the aileron are tangible following the speed and frequency of the wing flutter. Based on the proposed...
On the theoretical and molecular dynamic methods for natural frequencies of multilayer graphene nanosheets incorporating nonlocality and interlayer shear effects
, Article Mechanics of Advanced Materials and Structures ; Volume 29, Issue 20 , 2022 , Pages 2873-2883 ; 15376494 (ISSN) ; Taati, E ; Asghari, M ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
In this paper, a multiplate nonlocal shear model and molecular dynamic simulations are presented to investigate the effects of interlayer shear and nonlocality on the natural frequencies of multilayer graphene sheets (MLGSs). From one aspect in the optimal design of such structures, the interaction between graphene layers, which can significantly vary the static and dynamic behavior due to lack of solidity of layers stack, should be considered. On the other hand, it is requied that the nonlocality phenomenon which has an effective role in the mechanical analysis of nanostructures is taken into account. To this aim, the equation of motion along with corresponding boundary conditions is...
Buckling and vibration analysis of FG-CNTRC plate subjected to thermo-mechanical load based on higher order shear deformation theory
, Article Mechanics Based Design of Structures and Machines ; Volume 50, Issue 4 , 2022 , Pages 1137-1160 ; 15397734 (ISSN) ; Karbon, M ; Eyvazian, A ; Jung, D. W ; Habibi, M ; Safarpour, M ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
In the present study, based on 12-unknown higher order shear deformation theory (HSDT), buckling and vibration analysis of FG-CNTRC rectangular plate are investigated for various types of temperature distribution and boundary conditions. Implementing Hamilton’s principle, the equations of motion are derived and solved by adopting the Navier solution for the simply supported boundary conditions and DQM method for other boundary conditions. Validation is carried out by comparing the numerical results with those obtained in the open literature. Also, a detailed parametric analysis is carried out to illuminate the influence of different system parameters such as CNT distributions, CNT volume...
How does a microfluidic platform tune the morphological properties of polybenzimidazole nanoparticles?
, Article Journal of Physical Chemistry B ; Volume 126, Issue 1 , 2022 , Pages 308-326 ; 15206106 (ISSN) ; Sayyad Amin, J ; Zendehboudi, S ; Sharif University of Technology
American Chemical Society
2022
Abstract
Microfluidic synthesis methods are among the most promising approaches for controlling the size and morphology of polymeric nanoparticles (NPs). In this work, for the first time, atomistic mechanisms involved in morphological changes of polybenzimidazole (PBI) NPs in microfluidic media are investigated. The multiscale molecular dynamic (MD) simulations are validated with the literature modeling and experimental data. A good agreement is obtained between the molecular modeling results and experimental data. The effects of mixing time, solvent type, dopant, and simulation box size at the molecular level are investigated. Mixing time has a positive impact on the morphology of the PBI NPs....
The UV photodetection enhancement of tailored ZnO nanorods by controlling the aspect ratio
, Article Surfaces and Interfaces ; Volume 28 , 2022 ; 24680230 (ISSN) ; Rajabi, M ; Moshfegh, A. Z ; Sharif University of Technology
Elsevier B.V
2022
Abstract
ZnO Nanorods (NRs) are deposited on glass substrate using the hydrothermal method by applying a strategic growth control to improve their aspect ratios. In this research, the aspect ratio was tuned by tailoring the synthesis parameters, including the seed layer annealing temperature, absence/presence of polyethylenimine (PEI) in the growth solution, and the solution preheating process. The effects of these parameters on the morphology, crystal structure, room temperature photoluminescence properties, and current-voltage characteristics were examined by FESEM, XRD, PL, and I-V measurements. It was demonstrated that by varying the seed layer annealing temperature and presence of PEI solution...
Subsonic and supersonic flow-induced vibration of sandwich cylindrical shells with FG-CNT reinforced composite face sheets and metal foam core
, Article International Journal of Mechanical Sciences ; Volume 215 , 2022 ; 00207403 (ISSN) ; Fallah, F ; Ahmadian, M. T ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Based on the linear fluid-solid interaction (FSI) model and classical shell theories, vibration behavior of sandwich cylindrical shells subjected to external incompressible or compressible fluid flow is investigated. The sandwich shell includes the same outer and inner face sheets made of carbon nanotube (CNT) reinforced composites and a metal foam core. The effective mechanical properties of CNT reinforced composites are obtained using the extended rule of mixture. Also, the porosity distribution through the foam thickness is assumed to be in the form of a trigonometric function. Equations of motion and corresponding boundary conditions are derived according to the Donnell's, Love's and...
Secondary flows, mixing, and chemical reaction analysis of droplet-based flow inside serpentine microchannels with different cross sections
, Article Langmuir ; Volume 37, Issue 17 , 2021 , Pages 5118-5130 ; 07437463 (ISSN) ; Madadelahi, M ; Dizani, M ; Shamloo, A ; Sharif University of Technology
American Chemical Society
2021
Abstract
Chemical bioreactions are an important aspect of many recent microfluidic devices, and their applications in biomedical science have been growing worldwide. Droplet-based microreactors are among the attractive types of unit operations, which utilize droplets for enhancement in both mixing and chemical reactions. In the present study, a finite-volume-method (FVM) numerical investigation is conducted based on the volume-of-fluid (VOF) applying for the droplet-based flows. This multiphase computational modeling is used for the study of the chemical reaction and mixing phenomenon inside a serpentine microchannel and explores the effects of the aspect ratio (i.e., AR = height/width) of...
On the theoretical and molecular dynamic methods for natural frequencies of multilayer graphene nanosheets incorporating nonlocality and interlayer shear effects
, Article Mechanics of Advanced Materials and Structures ; 2021 ; 15376494 (ISSN) ; Taati, E ; Asghari, M ; Sharif University of Technology
Bellwether Publishing, Ltd
2021
Abstract
In this paper, a multiplate nonlocal shear model and molecular dynamic simulations are presented to investigate the effects of interlayer shear and nonlocality on the natural frequencies of multilayer graphene sheets (MLGSs). From one aspect in the optimal design of such structures, the interaction between graphene layers, which can significantly vary the static and dynamic behavior due to lack of solidity of layers stack, should be considered. On the other hand, it is requied that the nonlocality phenomenon which has an effective role in the mechanical analysis of nanostructures is taken into account. To this aim, the equation of motion along with corresponding boundary conditions is...
Providing Multicolor Plasmonic Patterns with Au@Ag Core-Shell Nanostructures for Visual Discrimination of Biogenic Amines
, Article ACS Applied Materials and Interfaces ; Volume 13, Issue 17 , 2021 , Pages 20865-20874 ; 19448244 (ISSN) ; Ghasemi, F ; Bigdeli, A ; Hormozi Nezhad, M. R ; Sharif University of Technology
American Chemical Society
2021
Abstract
Biogenic amines (BAs) are known as substantial indicators of the quality and safety of food. Developing rapid and visual detection methods capable of simultaneously monitoring BAs is highly desired due to their harmful effects on human health. In the present study, we have designed a multicolor sensor array consisting of two types of gold nanostructures (i.e., gold nanorods (AuNRs) and gold nanospheres (AuNSs)) for the discrimination and determination of critical BAs (i.e., spermine (SM), tryptamine (TT), ethylenediamine (EA), tyramine (TR), spermidine (SD), and histamine (HT)). The design principle of the probe was based on the metallization of silver ions on the surface of AuNRs and AuNSs...
Geometrically non-linear vibration of concrete shallow funicular shells
, Article Proceedings of the Institution of Civil Engineers: Structures and Buildings ; Volume 174, Issue 3 , 2021 , Pages 169-180 ; 09650911 (ISSN) ; Mofid, M ; Daneshmand, N ; Sharif University of Technology
ICE Publishing
2021
Abstract
This study deals with the geometrically non-linear vibration analysis of concrete shallow funicular shells of rectangular plan with four clamped edges under impulse loads. The shape of a concrete funicular shell is such that the shell is subjected to pure compression under its dead weight. Following the existing method presented for the linear vibration analysis, the geometrically non-linear vibration analysis is considered through the use of non-linear shallow shells theory. Each displacement component is expanded in a double Fourier series and the kinetic energy, the elastic strain energy and the virtual work done by external forces are calculated in terms of the displacement components....
Seismic evaluation of steel plate shear wall systems considering soil-structure interaction
, Article Soil Dynamics and Earthquake Engineering ; Volume 145 , 2021 ; 02677261 (ISSN) ; Shabanlou, M ; Meghdadi, Z ; Estekanchi, H. E ; Mofid, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
This study investigates the various effects of Soil-Structure Interaction (SSI) on the seismic behavior of steel frames with Steel Plate Shear Wall (SPSW) lateral resisting systems. Nine steel frames with various aspect ratios are studied under multiple seismic hazard levels. The SPSWs are modeled based on the strip model concept, and the Soil-Structure Systems are simulated using the substructure method. The soil beneath the structure is considered as a homogeneous elastic half-space. The Endurance Time method is exploited for nonlinear dynamic analysis of the fixed-base structures and soil-structure systems. Results indicate that use of fixed-base models leads to the significant...
The effect of nanopores geometry on desalination of single-layer graphene-based membranes: A molecular dynamics study
, Article Journal of Molecular Liquids ; Volume 339 , 2021 ; 01677322 (ISSN) ; Chogani, A ; Shariat, M ; Moosavi, A ; Kariminasab, H ; Sharif University of Technology
Elsevier B.V
2021
Abstract
The water desalination process using nanoporous single-layer graphene membranes is simulated through classical molecular dynamics. The effect of nanopores shapes on the capacity of the membrane for filtration of water is investigated. According to the results, the geometry of the nanopores considerably affects the performance of the membrane and can completely change the water flow rate and salt rejection. The results reveal that the effective area of the nanopores plays a critical role and for a better understanding of the impact of this parameter, aspect ratio and the equal diameter of noncircular pores based on different methods such as equal area, equal perimeter, and hydraulic diameter...