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A hydrogen-bonded extracellular matrix-mimicking bactericidal hydrogel with radical scavenging and hemostatic function for ph-responsive wound healing acceleration
, Article Advanced Healthcare Materials ; Volume 10, Issue 3 , 2021 ; 21922640 (ISSN) ; Correia, A ; Hasany, M ; Figueiredo, P ; Dobakhti, F ; Eskandari, M. R ; Hosseini, S. H ; Abiri, R ; Khorshid, S ; Hirvonen, J ; Santos, H. A ; Shahbazi, M. A ; Sharif University of Technology
Wiley-VCH Verlag
2021
Abstract
Generation of reactive oxygen species, delayed blood clotting, prolonged inflammation, bacterial infection, and slow cell proliferation are the main challenges of effective wound repair. Herein, a multifunctional extracellular matrix-mimicking hydrogel is fabricated through abundant hydrogen bonding among the functional groups of gelatin and tannic acid (TA) as a green chemistry approach. The hydrogel shows adjustable physicochemical properties by altering the concentration of TA and it represents high safety features both in vitro and in vivo on fibroblasts, red blood cells, and mice organs. In addition to the merit of facile encapsulation of cell proliferation-inducing hydrophilic drugs,...
The effect of improved cooling on the microstructure and mechanical properties of friction stir-welded advanced high-strength dual-phase steel
, Article Steel Research International ; Volume 92, Issue 2 , 2021 ; 16113683 (ISSN) ; Kokabi, A. H ; Goodarzi, M ; Kestens, L. A. I ; Sharif University of Technology
Wiley-VCH Verlag
2021
Abstract
The heat-affected zone (HAZ) softening is considered one of the most significant challenges during welding of ferrite–martensite dual-phase (DP) steels. In fact, the strain localization in the softened area results in a premature fracture that degrades the mechanical properties of the joint. Herein, the objective is to investigate the effectiveness of improved cooling using a high thermal diffusivity backing plate (BP) to reduce HAZ softening and enhance the mechanical properties of friction stir-welded DP700 steel. Accordingly, friction stir butt welding of DP700 steel was conducted using copper and mild steel BPs. The findings show that the replacement of steel BP with copper significantly...
Influence of residual stress on fatigue life of st-37 butt-mag weldment
, Article 12th International Conference on Metal Forming, METAL FORMING 2008, Krakow, 21 September 2008 through 24 September 2008 ; Volume 79, Issue 2 , 2008 , Pages 280-287 ; 16113683 (ISSN) ; Majzoobi, G. H ; Fadaee, A ; Sharif University of Technology
Wiley-VCH Verlag
2008
Abstract
In this paper residual stresses induced by butt metal arc gas welding (MAGW), in accordance with ASTM E837, are determined by hole drilling. The results are analyzed by probabilistic methods. Also, the effect of fatigue life on relaxation of welding residual stress is investigated. The specimens are tested to measure fatigue life and crack growth rates in accordance with ASTM E466 for force controlled amplitude axial fatigue testing. © 2008 Verlag Stahleisen GmbH, Düsseldorf
A hydrogen-bonded extracellular matrix-mimicking bactericidal hydrogel with radical scavenging and hemostatic function for ph-responsive wound healing acceleration
, Article Advanced Healthcare Materials ; Volume 10, Issue 3 , 2021 ; 21922640 (ISSN) ; Correia, A ; Hasany, M ; Figueiredo, P ; Dobakhti, F ; Eskandari, M. R ; Hosseini, S.H ; Abiri, R ; Khorshid, S ; Hirvonen, J ; Santos, H. A ; Shahbazi, M. A ; Sharif University of Technology
Wiley-VCH Verlag
2021
Abstract
Generation of reactive oxygen species, delayed blood clotting, prolonged inflammation, bacterial infection, and slow cell proliferation are the main challenges of effective wound repair. Herein, a multifunctional extracellular matrix-mimicking hydrogel is fabricated through abundant hydrogen bonding among the functional groups of gelatin and tannic acid (TA) as a green chemistry approach. The hydrogel shows adjustable physicochemical properties by altering the concentration of TA and it represents high safety features both in vitro and in vivo on fibroblasts, red blood cells, and mice organs. In addition to the merit of facile encapsulation of cell proliferation-inducing hydrophilic drugs,...
Effects of ion-carrier substituents on the potentiometric-response characteristics in anion-selective membrane electrodes based on iron porphyrins
, Article ChemPhysChem ; Volume 5, Issue 5 , 2004 , Pages 652-660 ; 14394235 (ISSN) ; Seifi, H ; Bagherzadeh, M ; Mousavi, S. R ; Sharif University of Technology
Wiley-VCH Verlag
2004
Abstract
The potentiometric response characteristics with respect to salicylate anion of several membrane electrodes based on iron(II) tetraphenylporphyrin chloride (FeTPPCl) and derivatives with electrophilic and nucleophilic substituents, incorporated into plasticized polyvinylchloride (PVC) membranes were investigated. Complexes tetraphenyl porphyrin iron(III) chloride (FeTPPCl; A), tetrakis (4-methoxyphenyl) porphyrin iron(III) chloride (Fe(TOCH 3PP)Cl; B), tetrakis (2,6-dichlorophenyl) porphyrin iron(III) chloride (Fe(TDClPP)Cl; C), tetrakis (4-nitrophenyl) porphyrin iron(III) chloride (Fe(TNO2PP)Cl; D), and tetrakis (pentafluorophenyl) porphyrin iron(III) chloride (Fe(TPFPP)Cl; E) were used as...
Worm-like micelles:a new approach for heavy oil recovery from fractured systems
, Article Canadian Journal of Chemical Engineering ; Volume 93, Issue 5 , 2015 , Pages 951-958 ; 00084034 (ISSN) ; Saidian, M ; Mavaddat, M ; Ghazanfari, M. H ; Kharrat, R ; Rashtchian, D ; Sharif University of Technology
Wiley-Liss Inc
2015
Abstract
In this work, a new type of flooding system, "worm-like micelles", in enhanced heavy oil recovery (EOR) has been introduced. Application of these types of surfactants, because of their intriguing and surprising behaviour, is attractive for EOR studies. Fundamental understanding of the sweep efficiencies as well as displacement mechanisms of this flooding system in heterogeneous systems especially for heavy oils remains a topic of debate in the literature. Worm-like micellar surfactant solutions are made up of highly flexible cylindrical aggregates. Such micellar solutions display high surface activity and high viscoelasticity, making them attractive in practical applications for EOR. In this...
Kinetic modelling of enzymatic biodiesel production from castor oil: Temperature dependence of the Ping Pong parameters
, Article Canadian Journal of Chemical Engineering ; Volume 94, Issue 3 , 2016 , Pages 512-517 ; 00084034 (ISSN) ; Kariminia, H. R ; Khorasheh, F ; Sharif University of Technology
Wiley-Liss Inc
2016
Abstract
Biodiesel is considered an alternative replacement for petroleum diesel, and enzymatic reaction is one method for biodiesel production. Understanding the kinetics of this reaction is important to achieve higher production rates. The kinetics of transesterification of castor oil using Novozym 435 was investigated in this study. The genetic algorithm was employed for estimation of kinetic parameters including Vmax, KmTG, and KmA in the Ping Pong kinetic model at different temperatures. In most enzymatic reactions that follow the Ping Pong mechanism, inhibition by alcohol has been taken into consideration. Here, we examined a competitive inhibition mechanism and found no inhibition effect at...
Wettability alteration of reservoir rocks to gas wetting condition: a comparative study
, Article Canadian Journal of Chemical Engineering ; Volume 96, Issue 4 , April , 2018 , Pages 997-1004 ; 00084034 (ISSN) ; Ghazanfari, M. H ; Karimi Malekabadi, F ; Sharif University of Technology
Wiley-Liss Inc
2018
Abstract
Productivity of gas condensate reservoirs reduces significantly due to the near wellbore condensate/water blockage phenomenon. A novel, permanent solution to alleviate this problem is near wellbore wettability alteration of reservoir rocks to preferentially gas wetting conditions; industrial chemical materials are good candidates for this purpose, because of their eco-friendly characteristics, economical price, and mass production. In this paper, a comparative study is conducted on two industrial fluorinated chemicals, MariSeal 800 and SurfaPore M. Static and dynamic contact angle measurements, spontaneous imbibition, and core flooding tests were conducted to investigate the effect of...
Effect of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement
, Article Canadian Journal of Chemical Engineering ; Volume 95, Issue 1 , 2017 , Pages 83-91 ; 00084034 (ISSN) ; Ramazani S. A, A ; Alijani Alijanvand, H ; Ghazanfari, M. H ; Ghanavati, M ; Sharif University of Technology
Wiley-Liss Inc
2017
Abstract
The highly viscous property of heavy oil often causes problems in its transportation in pipelines. Mixing heavy oil with light oil as well as ultrasound treatment are viable solutions to this problem. In this study, extra heavy crude oil samples were first diluted with 0, 0.05, 0.1, and 0.15 mL/mL (0, 5, 10, and 15 vol%) of a light crude oil; then the mixture was irradiated by ultrasonic waves for 0, 5, 10, 15, and 20 min; finally the viscous shear functions of all mixtures was measured at different values of shear rate at different temperature levels. The results revealed that the minimum viscosity of the diluted extra heavy crude oil samples was obtained at 10 min of ultrasonic...
Equimatchable regular graphs
, Article Journal of Graph Theory ; Volume 87, Issue 1 , 2018 , Pages 35-45 ; 03649024 (ISSN) ; Ghodrati, A. H ; Hosseinzadeh, M. A ; Iranmanesh, A ; Sharif University of Technology
Wiley-Liss Inc
2018
Abstract
A graph is called equimatchable if all of its maximal matchings have the same size. Kawarabayashi, Plummer, and Saito showed that the only connected equimatchable 3-regular graphs are K4 and K3, 3. We extend this result by showing that for an odd positive integer r, if G is a connected equimatchable r-regular graph, then G ϵ {Kr+1, Kr,r}. Also it is proved that for an even r, a connected triangle-free equimatchable r-regular graph is isomorphic to one of the graphs C5, C7, and Kr,r. © 2017 Wiley Periodicals, Inc
Combinational therapy of lithium and human neural stem cells in rat spinal cord contusion model
, Article Journal of Cellular Physiology ; Volume 234, Issue 11 , 2019 , Pages 20742-20754 ; 00219541 (ISSN) ; Sadrosadat, H ; Jaberi, R ; Zareikheirabadi, M ; Mirsadeghi, S ; Naghdabadi, Z ; Ghaneezabadi, M ; Fardmanesh, M ; Baharvand, H ; Kiani, S ; Sharif University of Technology
Wiley-Liss Inc
2019
Abstract
A large number of treatment approaches have been used for spinal cord injury improvement, a medically incurable disorder, and subsequently stem cell transplantation appears to be a promising strategy. The main objective of this study is to ascertain whether combinational therapy of human neural stem cells (hNSCs) together with lithium chloride improves cell survival, proliferation, and differentiation in a rat spinal contusion model, or not. Contusive spinal cord injury was implemented on Wistar male rats. Experimental groups comprised of: control, hNSCs transplanted, lithium chloride (Li), and hNSCs and lithium chloride (hNSCs + Li). In every experimental group, locomotor activity score and...
Targeting AMPK signaling pathway by natural products for treatment of diabetes mellitus and its complications
, Article Journal of Cellular Physiology ; Volume 234, Issue 10 , 2019 , Pages 17212-17231 ; 00219541 (ISSN) ; Singh, A. K ; Haratipour, P ; Sah, A. N ; Pandey, A. K ; Naseri, R ; Juyal, V ; Farzaei, M. H ; Sharif University of Technology
Wiley-Liss Inc
2019
Abstract
Diabetes affects a large population of the world. Lifestyle, obesity, dietary habits, and genetic factors contribute to this metabolic disease. A target pathway to control diabetes is the 5′-adenosine monophosphate-activated protein kinase (AMPK) signaling pathway. AMPK is a heterotrimeric protein with α, β, and γ subunits. In several studies, AMPK activation enhanced glucose uptake into cells and inhibited intracellular glucose production. Impairment of AMPK activity is present in diabetes, according to some studies. Drugs used in the treatment of diabetes, such as metformin, are also known to act through regulation of AMPK. Thus, drugs that activate and regulate AMPK are potential...
Graph homomorphisms through random walks
, Article Journal of Graph Theory ; Volume 44, Issue 1 , 2003 , Pages 15-38 ; 03649024 (ISSN) ; Hajiabolhassan, H ; Sharif University of Technology
Wiley-Liss Inc
2003
Abstract
In this paper we introduce some general necessary conditions for the existence of graph homomorphisms, which hold in both directed and undirected cases. Our method is a combination of Diaconis and Saloff-Coste comparison technique for Markov chains and a generalization of Haemers interlacing theorem. As some applications, we obtain a necessary condition for the spanning subgraph problem, which also provides a generalization of a theorem of Mohar (1992) as a necessary condition for Hamiltonicity. In particular, in the case that the range is a Cayley graph or an edge-transitive graph, we obtain theorems with a corollary about the existence of homomorphisms to cycles. This, specially, provides...
Circular chromatic index of graphs of maximum degree 3
, Article Journal of Graph Theory ; Volume 49, Issue 4 , 2005 , Pages 325-335 ; 03649024 (ISSN) ; Ghandehari, M ; Ghandehari, M ; Hatami, H ; Tusserkani, R ; Zhu, X ; Sharif University of Technology
Wiley-Liss Inc
2005
Abstract
This paper proves that if G is a graph (parallel edges allowed) of maximum degree 3, then χc′(G) ≤ 11/3 provided that G does not contain H1 or H2 as a subgraph, where H1 and H2 are obtained by subdividing one edge of K23 (the graph with three parallel edges between two vertices) and K4, respectively. As χc′(H1) = χ c′(H2) = 4, our result implies that there is no graph G with 11/3 < χc′(G) < 4. It also implies that if G is a 2-edge connected cubic graph, then χc′(G) ≤ 11/3. © 2005 Wiley Periodicals, inc
On the effect of temperature on precipitation and aggregation of asphaltenes in light live oils
, Article Canadian Journal of Chemical Engineering ; Volume 94, Issue 9 , 2016 , Pages 1820-1829 ; 00084034 (ISSN) ; Rashidi, F ; Mousavi Dehghani, S. A ; Ghazanfari, M. H ; Sharif University of Technology
Wiley-Liss Inc
2016
Abstract
Asphaltene precipitation and deposition is a serious issue in all facets of petroleum production and processing. Despite the numerous experimental efforts concerning asphaltenes, the effect of temperature on asphaltene precipitation and aggregation in live oils remains an elusive and controversial subject in the available literature. In this work, a series of high pressure-high temperature depressurization experiments were designed to assess the effect of temperature on asphaltene precipitation and aggregation in light live oils. Asphaltene related experiments were performed using a high pressure microscope and high pressure-high temperature filtration setup on a light live oil with a low...
Accurate determination of the CO2-crude oil minimum miscibility pressure of pure and impure CO2 streams: A robust modelling approach
, Article Canadian Journal of Chemical Engineering ; Volume 94, Issue 2 , 2016 , Pages 253-261 ; 00084034 (ISSN) ; Ghazanfari, M. H ; Ayatollahi, S ; Masihi, M ; Sharif University of Technology
Wiley-Liss Inc
2016
Abstract
Gas flooding processes have emerged as attractive enhanced oil recovery (EOR) methods over the last few decades. Among different gas flooding processes, CO2 flooding is recognized as being most efficient for displacing oil through miscible displacement. Minimum miscibility pressure (MMP) is a crucial parameter for successfully designing CO2 flooding, which is traditionally measured through time-consuming, expensive, and cumbersome experiments. In the present study, a new reliable model based on feed-forward artificial neural networks was presented to predict both pure and impure CO2-crude oil MMP. Among various properties and parameters, reservoir temperature, reservoir oil composition, and...
Nonlinear analysis and attitude control of a gyrostat satellite with chaotic dynamics using discrete-time LQR-OGY
, Article Asian Journal of Control ; 2016 ; 15618625 (ISSN) ; Sadati, S. H ; Salarieh, H ; Sharif University of Technology
Wiley-Blackwell
2016
Abstract
Quasi-periodic and chaotic behavior, along with the control of chaos for a Gyrostat satellite (GS), is investigated in this work. The quaternion-based dynamical model of the GS is first derived, and then the influences of the reaction wheels in the GS structure, under the gravity gradient perturbation that causes a route to chaos through quasi-periodicity mechanism, is investigated. For the suppression of chaos in the system, a chaos control system with the quaternion feedback is designed for the GS based on the extension of the Ott-Grebogi-Yorke (OGY) method using the linearization of the Poincaré map. In the extended OGY controller, the Poincaré map is estimated using the Least Square...
Magnetic nanocomposite of cross-linked Mmelamine groups decorated with large amounts of gold NPs: reduction of nitro compounds and Suzuki–Miyaura coupling reactions in aqueous media
, Article ChemistrySelect ; Volume 3, Issue 10 , March , 2018 , Pages 2716-2722 ; 23656549 (ISSN) ; Keshavarzi, N ; Matloubi Moghaddam, F ; Hosseini, S. H ; Sharif University of Technology
Wiley-Blackwell
2018
Abstract
A magnetic nanocomposite was prepared based on magnetic Fe3O4 nanoparticles entrapped into a cross-linked nitrogen rich polymer which has high loading capacity for immobilization of gold nanoparticles. The synthesized catalyst was characterized using various methods including Atomic absorption spectroscopy (AAS), Transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), Energy-dispersive X-ray spectroscopy (EDX), Thermogravimetric analysis (TGA), scanning electron microscope (SEM), Brunauer–Emmett–Teller (BET), VSM and X-ray diffraction (XRD) techniques. The catalyst was proven to be highly efficient for reduction of nitroarenes as well as Suzuki–Miyaura...
Accuracy analysis of an integrated inertial navigation system in slow maneuvers
, Article Navigation, Journal of the Institute of Navigation ; 2017 ; 00281522 (ISSN) ; Mohammadkarimi, H ; Sharif University of Technology
Wiley-Blackwell
2017
Abstract
In-motion alignment of a strapdown inertial navigation system, during slow maneuvers, is studied. Terrestrial velocity is fed back to the navigation system to estimate and compensate for the navigation errors. Observability of the errors is analyzed since the integrated navigation system is not fully observable. Then, the accuracy bounds of the navigation system in different motion scenarios are obtained analytically. Also, in order to minimize the errors of the navigation system, special maneuvers are designed based on the analytical derivations. The analytical results, obtained using the linearized error model, are verified through nonlinear simulation of different maneuvering and...
A model aided inertial navigation system for automatic landing of unmanned aerial vehicles
, Article Navigation, Journal of the Institute of Navigation ; Volume 65, Issue 2 , June , 2018 , Pages 183-204 ; 00281522 (ISSN) ; Nobahari, H ; Sharif University of Technology
Wiley-Blackwell
2018
Abstract
The use of Model Aided Inertial Navigation (MAIN) during the landing of an Unmanned Aerial Vehicle (UAV) is investigated. A new MAIN algorithm is proposed, which is fast and accurate enough to be used in automatic landing. In this algorithm, the six Degree of Freedom (6DoF) model of the UAV is tightly coupled with the inertial navigation system; thus, the 6DoF model acts as an aiding system for the INS and vice versa. In the last parts of the landing phase in proximity of Earth, the proposed algorithm also estimates and removes the Ground Effect (GE) uncertainties and provides the height controller with a realistic model. An adaptive controller based on a parametric state-space model is used...