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deposition-rates
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Mechanistic study to investigate the effects of different gas injection scenarios on the rate of asphaltene deposition: An experimental approach
, Article Fuel ; Volume 262 , 2020 ; Zanganeh, P ; Kord, S ; Ayatollahi, S ; Amiri, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Asphaltene deposition during enhanced oil recovery (EOR) processes is one of the most problematic challenges in the petroleum industry, potentially resulting in flow blockage. Our understanding of the deposition mechanism with emphasis on the rate of the asphaltene deposition is still in its infancy and must be developed through a range of experiments and modelling studies. This study aims to investigate the rate of asphaltene deposition through a visual study under different gas injection scenarios. To visualise the asphaltene deposition, a high-pressure setup was designed and constructed, which enables us to record high-quality images of the deposition process over time. Present research...
A study of the electrophoretic deposition of Bioglass® suspensions using the Taguchi experimental design approach
, Article Journal of the European Ceramic Society ; Volume 30, Issue 14 , October , 2010 , Pages 2963-2970 ; 09552219 (ISSN) ; Simchi, A ; Ryan, M. P ; Boccaccini, A. R ; Sharif University of Technology
2010
Abstract
This paper presents a study of the Taguchi design method to optimise the rate of electrophoretic deposition (EPD) of Bioglass® particles from aqueous suspensions. The effect of Bioglass® concentration, pH and electric field was investigated. An orthogonal array of L16 type with mixed levels of the control factors was utilized. Multivariate analysis of variance (MANOVA) and regression analysis based on the partial least-square method were used to identify the significant factors affecting the deposition rate and its stability during constant-voltage EPD. It was found that the pH of the suspension significantly influences the deposition rate whereas the applied electric field has the smallest...
Electrodeposition of Zn–Ni–P compositionally modulated multilayer coatings: An attempt to deposit Ni–P and Zn–Ni alloys from a single bath
, Article Electrochemistry Communications ; Volume 81 , 2017 , Pages 93-96 ; 13882481 (ISSN) ; Ghorbani, M ; Sharif University of Technology
Elsevier Inc
2017
Abstract
The effects of bath composition and deposition variables on the electrodeposition of Zn–Ni–P alloys were studied in order to develop a single bath for deposition of Ni–P/Zn–Ni compositionally modulated multilayer coatings (CMMCs). The basis for development of the bath was a large increase in the Ni deposition rate compared to that of Zn at low deposition overpotentials combined with the impossibility of codeposition of Zn with P. EDS analysis demonstrated that the deposits obtained from the Zn–Ni–P bath at low overpotentials were practically all Ni–P, while the alloy deposited at high overpotentials was mainly Zn–Ni with around 3.2 wt% P content. © 2017 Elsevier B.V
Prediction of asphaltene deposition during turbulent flow using heat transfer approach
, Article Petroleum Science and Technology ; Volume 36, Issue 9-10 , February , 2018 , Pages 632-639 ; 10916466 (ISSN) ; Ayatollahi, S ; Vafaie Seftie, M ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
In this study, asphaltene deposition from crude oil has been studied experimentally using a test loop and prediction using theoretical study under turbulent flow (Reynolds numbers below 5000). The effects of many parameters such as oil velocity, surface temperature and concentration of flocculated asphaltene on the asphaltene deposition were investigated. The results showed that asphaltene deposition thickness increases with increasing both surface temperature and concentration of flocculated asphaltene and decreasing oil velocity. Thermal approach was used to describe the mechanisms involved in this process and the results of data fitting showed that there are good agreements between the...
Electrophoretic deposition of chitosan/45S5 Bioglass® composite coatings for orthopaedic applications
, Article Surface and Coatings Technology ; Volume 205, Issue 23-24 , 2011 , Pages 5260-5268 ; 02578972 (ISSN) ; Simchi, A ; Ryan, M. P ; Boccaccini, A. R ; Sharif University of Technology
2011
Abstract
This article presents experimental results on the electrophoretic deposition (EPD) of bioresorbable chitosan/45S5 Bioglass® composite coatings for orthopaedic implants based on the Taguchi design of experiments (DOE) approach. The influence of EPD parameters including Bioglass® concentration, electric voltage and deposition time on deposition yield was studied by an orthogonal Taguchi array of L18 type. Multivariate analysis of variance (MANOVA) and regression analysis based on the partial least-square method were used to identify the significant factors affecting the deposition yield and its stability during constant-voltage EPD. The coatings were characterised by high resolution scanning...
Corrosion resistance enhancement of Ni-P-nano SiO2 composite coatings on aluminum
, Article Applied Surface Science ; Vol. 303 , 2014 , Pages 125-130 ; ISSN: 01694332 ; Afshar, A ; Sharif University of Technology
Abstract
In this study, the influences of different concentrations of SiO 2 nano sized particles in the bath on deposition rate, surface morphology and corrosion behavior of Ni-P-SiO2 Composite coatings were investigated. The deposition rate of coating was influenced by incorporation of SiO2 particles. The microstructure was investigated with field emission scanning electron microscopy (FESEM). The amount of SiO 2 was examined by Energy Dispersive Analysis of X-Ray (EDX) and amount of SiO2 nanoparticles co-deposited reached a maximum value at 4.5 %wt. Corrosion behavior of coated aluminum was evaluated by electrochemical impedance spectroscopy (EIS) and polarization techniques. The results...
Tribological properties of Ni–P–SiO2 nanocomposite coating on aluminum
,
Article
Colloid Journal
;
Volume 77, Issue 5
,
September
,
2015
,
Pages 628-634
;
1061933X (ISSN)
; Afshar, A
; Jazani, M. A
;
Sharif University of Technology
Maik Nauka Publishing / Springer SBM
2015
Abstract
In this study, the effects of different concentrations of SiO2 nanosized particles in the bath on deposition rate, surface morphology and wear behavior of Ni–P–SiO2 composite coatings were investigated. The rate of coating deposition was influenced by the incorporation of SiO2 particles. The observations of microstructural morphology were performed with field emission scanning electron microscopy. The amount of deposited SiO2 was examined by X-ray energy dispersive analysis. The results showed that for the coating produced at 12.5 g/L of nanoparticles, the amount of co-deposited SiO2 nanoparticles and microhardness reached their maximal...
Experimental investigation of the effect of inlet concentration on the behavior of turbidity currents in the presence of two consecutive obstacles
, Article Journal of Waterway, Port, Coastal and Ocean Engineering ; Volume 143, Issue 2 , 2017 ; 0733950X (ISSN) ; Afshin, H ; Firoozabadi, B ; Farizan, A ; Sharif University of Technology
American Society of Civil Engineers (ASCE)
2017
Abstract
Turbidity currents are often the main processes of sediment transport in deep waters and reservoirs. To prevent sedimentation in critical locations, various methods, such as placing solid obstacles in the path of these flows, have been proposed. In the present study, the effect of inlet concentration on the behavior of turbidity currents in the presence of two consecutive triangular obstacles was investigated experimentally. For this purpose, a series of laboratory experiments were conducted with various inlet concentrations. In each experiment, velocity and concentration profiles were measured using an acoustic Doppler velocimeter. The velocity of the current head and local Froude number...
Measurement and prediction of the rate of deposition of flocculated asphaltene particles from oil
, Article International Journal of Heat and Mass Transfer ; Volume 52, Issue 19-20 , 2009 , Pages 4624-4634 ; 00179310 (ISSN) ; Soltani, B ; Müller Steinhagen, H ; Rashtchian, D ; Sharif University of Technology
2009
Abstract
Asphaltene deposition is one of the unresolved problems in oil industries. Little information is available on the critical question of "how fast" the flocculated asphaltene particles deposit across the production wells from the flowing oil. In this study, the mechanisms of deposition of flocculated asphaltene particles from oil have been studied experimentally and theoretically under forced convective conditions using an accurate thermal approach. The effects of oil velocity, flocculated asphaltene concentration and temperature on the rate of asphaltene deposition are investigated. It is observed that during the first few weeks the deposition mechanism is dominant and the erosion of the...
Atheroprone sites of coronary artery bifurcation: Effect of heart motion on hemodynamics-dependent monocytes deposition
, Article Computers in Biology and Medicine ; Volume 133 , 2021 ; 00104825 (ISSN) ; Firoozabadi, B ; Saidi, M. S ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Atherosclerosis as a common cardiovascular disease is a result of both adverse hemodynamics conditions and monocyte deposition within coronary arteries. It is known that the adhesion of monocytes on the arterial wall and their interaction with the vascular surface are one of the main parameters in the initiation and progression of atherosclerosis. In this work, hemodynamic parameters and monocyte deposition have been investigated in a 3D computational model of the Left Anterior Descending coronary artery (LAD) and its first diagonal branch (D1) under the heart motion. A one-way Lagrangian approach is performed to trace the monocyte particles under different blood flow regimes and heart motion...