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tio2-nanoparticles
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Synthesis of titanium oxide nanotubes and their decoration by MnO nanoparticles for biomedical applications
, Article Ceramics International ; Volume 45, Issue 15 , 2019 , Pages 19275-19282 ; 02728842 (ISSN) ; Mahmoudi, P ; Zamanian, A ; Mozafari, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this study, apatite formation ability on TiO2 nanotubes (TNTs) synthesized by anodizing process were compared with TNTs decorated by MnO nanoparticles. The MnO nanoparticles used for decoration process were fabricated via thermal decomposition method. At first, it was strived to find the optimal condition of anodizing process and the effect of applied voltages (15 V, 20 V, and 25 V) and process times (15 min, 20 min, and 25 min) on the diameter of the synthesized TNTs was investigated. Results of microscopic characterizations showed that the completely uniform structure of nanotubes with a diameter in the range of about 100–130 nm was achieved after 20 min of anodizing process at an...
Synthesis of composite coating containing tio2 and ha nanoparticles on titanium substrate by ac plasma electrolytic oxidation
, Article Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science ; Volume 50, Issue 7 , 2019 , Pages 3310-3319 ; 10735623 (ISSN) ; Ghorbani, M ; Chambari, E ; Sharif University of Technology
Springer Boston
2019
Abstract
In this study, biocompatible ceramic layers containing TiO2 and hydroxyapatite (HA) nanoparticles (TiO2/HA) were deposited on pure commercial titanium (Grade 2) by using plasma electrolytic oxidation and AC power supply. The coating process was carried out in five different solutions for various times at a current density of 500 mA cm−2. To achieve the optimum conditions for thickness and microstructure, the coating process was conducted in solutions with a 3 g L−1 concentration of HA nanoparticles. FESEM, XRD, and FTIR results showed that HA nanoparticles were successfully incorporated into the pores of the layer. Furthermore, the corrosion behavior of the coating layers in the simulated...
Fluidity enhancement of hard-to-fluidize nanoparticles by mixing with hydrophilic nanosilica and fluid catalytic cracking particles: Experimental and theoretical study
, Article Physics of Fluids ; Volume 31, Issue 7 , 2019 ; 10706631 (ISSN) ; Rahimvandi Noupoor, Y ; Badamchizadeh, P ; Sharif University of Technology
American Institute of Physics Inc
2019
Abstract
As a low-cost method, hydrophilic SiO2 nanoparticles (NPs) and fluid catalytic cracking (FCC) coarse particles were used as assistant materials to improve the fluidity of Al2O3 and TiO2 hard-to-fluidize nanopowders. To decrease the strong electrostatic forces between the hydrophilic nanopowders, prepared samples were fluidized in the presence of methanol vapor. Results revealed that the amount of SiO2 NPs, increased from 5 to 50 wt. %, has a beneficial effect on the fluidization quality of the binary (hard-to-fluidize NPs + SiO2) and ternary (hard-to-fluidize NPs + SiO2 + FCC) mixtures. However, the amount of FCC particles when it varied from 15 to 30 wt. % in the ternary mixtures should...
Synthesis of porous TiO2/ZrO2 photocatalyst derived from zirconium metal organic framework for degradation of organic pollutants under visible light irradiation
, Article Journal of Environmental Chemical Engineering ; Volume 7, Issue 3 , 2019 ; 22133437 (ISSN) ; Yahyanezhad, M ; Sakhaie, S ; Vossoughi, M ; Alemzadeh, I ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Zirconium based metal-organic frameworks (Zr-MOFs) are promising candidates for photocatalytic wastewater treatment due to their excellent properties such as high chemical and thermal stability and high photodegradation ability. Herein, we report a novel porous TiO2/ZrO2 photocatalyst derived from UiO-66 and Titania hybrids. UiO-66 nanoparticles was synthesized through solvothermal method and utilized as catalyst support to grow TiO2 particles on its surface. The prepared Titania/MOF nanocomposite was calcined to obtain porous TiO2/ZrO2 photocatalyst for degradation of organic pollutants from colored wastewater under LED visible light. The prepared materials were fully characterized with...
Microstructural evaluation and mechanical properties of Al1050/TiO 2 -Graphite hybrid nanocomposite produced Via friction stir processing
, Article Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science ; Volume 50, Issue 5 , 2019 , Pages 2443-2461 ; 10735623 (ISSN) ; Movahedi, M ; Kokabi, A. H ; Sharif University of Technology
Springer Boston
2019
Abstract
Production of Al1050/TiO 2 -graphite hybrid nanocomposite via friction stir processing (FSP) was studied. The effect of graphite-to-TiO 2 volume fraction ratio (Gr/TiO 2 ), at a constant rotational speed (ω) and three levels of tool traverse speed (ν), on the microstructural evolution and mechanical properties of the nanocomposites was investigated. While TiO 2 is supposed to enhance the strength and hardness, graphite is believed to improve the tribological behavior. Furthermore, formation of intermetallic compounds (IMCs) through the solid-state reactions between the reinforcements and aluminum matrix may also promote the mechanical properties. To assess these assumptions, longitudinal and...
New approaches in lowering the gas-phase synthesis temperature of TiO2 nanoparticles by H2O-assisted atmospheric pressure CVS process
, Article Journal of Materials Research and Technology ; Volume 8, Issue 3 , 2019 , Pages 3024-3035 ; 22387854 (ISSN) ; Saberyan, K ; Simchi, A ; Gammer, C ; Sharif University of Technology
Elsevier Editora Ltda
2019
Abstract
H2O-assisted atmospheric pressure chemical vapor synthesis is a modern economical process for the gas-phase synthesis of TiO2 nanoparticles. In the present work, the influence of synthesis temperatures (100-800 °C) on the phase structure, nanoparticle size, morphology, and agglomeration is investigated by transmission electron microscopy, selected area electron diffraction, X-ray diffraction, thermogravimetry, and differential thermal analysis. Down to 400 °C, crystalline TiO2 nanoparticles are synthesized and at 200 °C amorphous nanoparticles are formed. Therefore, a decrease in minimum synthesis temperature by more than 500 °C is achieved. In addition, the paper investigates the hypothesis...
Improving the performance of a photonic PCR system using TiO2 nanoparticles
, Article Journal of Industrial and Engineering Chemistry ; 2020 ; Ghazimirsaeed, E ; Shamloo, A ; Dizani, M ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2020
Abstract
Nucleic acid amplification using polymerase chain reaction (PCR) method has been widely used in different fields such as agricultural science, medicine, pathogen identification, and forensics to name a few. Today, it seems inevitable to have a robust, simple PCR system for diagnostics at the point-of-care (POC) level. Many photonic PCR systems have been proposed in the literature that benefit from plasmonic photothermal heating to achieve the common PCR thermal cycling. However, non-homogeneous temperature distribution is a challenge in some of them. In the present work, to achieve more efficient gene amplification, the effect of adding TiO2 nanoparticles has been investigated in a photonic...
A novel superhydrophilic/superoleophobic nanocomposite PDMS-NH2/PFONa-SiO2 coated-mesh for the highly efficient and durable separation of oil and water
, Article Surface and Coatings Technology ; Volume 394 , 2020 ; Siavash Moakhar, R ; Dolati, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A surface to separate oil–water mixtures is a global concern and highly needed particularly in oil industries. The present study was conducted to create a novel superhydrophilic/superoleophobic nanocomposite coating on the stainless-steel mesh for the aim of oil/water separation. Different hydrophilic resins along with PFOA as oleophobic agent with 15 flours in its chemical structure and various oxide nanoparticles containing SiO2 and TiO2 at different concentrations were studied to achieve superhydrophilic/superoleophobic surface. The fabricated nanocomposites were fully characterized via field-emission scanning microscopy (FESEM), atomic force microscopy (AFM) and Fourier-transform...
Sustained release of CIP from TiO2-PVDF/starch nanocomposite mats with potential application in wound dressing
, Article Journal of Applied Polymer Science ; Volume 137, Issue 30 , 2020 ; Haddadi, S. A ; Amini, M ; Hasany, M ; Ramazani SaadatAbadi, A ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
Electrospinning is an economical and alluring method to fabricate wound dressing mats from a variety of natural and synthetic materials. In this study, polyvinylidene fluoride (PVDF) and starch composite mats containing ciprofloxacin (CIP) loaded on titanium dioxide nanoparticles (TiO2) were prepared. Fourier Transform Infrared spectra of CIP, synthesized TiO2 NPs, TiO2/CIP, and PVDF/starch composite mats are analyzed. Scanning electron microscopy images revealed that the fiber diameter of PVDF nanofibers thickens by increasing starch, which varies between 180 nm and 550 nm. Strain at break of PVDF, starch, PVDF/starch (2:1 w:w; P2S1), PVDF/starch (1:1 w:w; P1S1), PVDF/starch (1:2 w:w;...
Improvement of performance and fouling resistance of polyamide reverse osmosis membranes using acrylamide and TiO2 nanoparticles under UV irradiation for water desalination
, Article Journal of Applied Polymer Science ; Volume 137, Issue 11 , 2020 ; Bastani, D ; Mousavi, S. A ; Heydari, H ; Vaghar Mousavi, D ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
The purpose of this research is to explain the surface modification of fabricated polyamide reverse osmosis (RO) membranes using UV-initiated graft polymerization at different irradiation times (15, 30, 60, and 90 s) and various acrylamide concentrations (10, 20, and 30 g L−1). Also, coating of membranes surface with various concentrations of TiO2 nanoparticles (10, 20, 30, and 50 ppm) followed by the same UV irradiation times was investigated. After that, the membranes modification was done by grafting of acrylamide blended with TiO2 nanoparticles via UV irradiation. The characterization of membranes surface properties and their performance were systematically carried out. The results...
Effect of metal oxide based TiO2 nanoparticles on anaerobic digestion process of lignocellulosic substrate
, Article Energy ; Volume 191 , 2020 ; Baniamerian, H ; Tsapekos, P ; Alvarado Morales, M ; Kasama, T ; Shahrokhi, M ; Vossoughi, M ; Angelidaki, I ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Lignocellulosic materials are recalcitrant to bioconversion, due to their rigid physiochemical structure. In this work, the effects of Fe2O3–TiO2 and NiO–TiO2 nanoparticles (NPs) and FeCl3 and NiCl2 salts, on the anaerobic digestion (AD) of wheat straw have been investigated. For this purpose, metal oxide-TiO2 NPs were synthesized and fully characterized. Results showed that addition of 0.252 mg of NiO–TiO2/g total solids (TS) to batch assays resulted in increase of soluble chemical oxygen demand (COD) and 67% increase in volatile fatty acids (VFAs) concentration compared to control tests during the first 4 days of experiments. These results indicate that hydrolysis and acidogenesis rates...
Heterostructured TiO2/SiO2/γ-Fe2O3/rGO coating with highly efficient visible-light-induced self-cleaning properties for metallic artifacts
, Article ACS Applied Materials and Interfaces ; Volume 12, Issue 26 , 3 June , 2020 , Pages 29671-29683 ; Kaveh, R ; Bagherzadeh, M ; Lucotti, A ; Pedeferri, M ; Diamanti, M. V ; Sharif University of Technology
American Chemical Society
2020
Abstract
A novel nanohybrid composite of TiO2, SiO2, γ-Fe2O3, and reduced graphene oxide (TiO2@Si:Fe:rGO) is fabricated by the sol-gel method. The properties of the coated film were examined by structural and self-cleaning analyses using simulated discoloration/soiling and roofing tests. The fabricated transparent TiO2@Si:Fe:rGO composite showed excellent photoactivity and wettability, behaving well in self-cleaning applications. The addition of SiO2 improved the crystalline structure and surface hydroxylation of TiO2 nanoparticles. γ-Fe2O3 decreased the recombination rate of e-/h+ pairs, and significantly improved photocatalytic activity under visible light. Moreover, rGO sheets as excellent...
Mechanical modeling of silk fibroin/TiO2 and silk fibroin/fluoridated TiO2 nanocomposite scaffolds for bone tissue engineering
, Article Iranian Polymer Journal (English Edition) ; Volume 29, Issue 3 , February , 2020 , Pages 219-224 ; Madaah Hosseini, H. R ; Samadikuchaksaraei, A ; Sharif University of Technology
Springer
2020
Abstract
Biocompatible and biodegradable three-dimensional scaffolds are commonly porous which serve to provide suitable microenvironments for mechanical supporting and optimal cell growth. Silk fibroin (SF) is a natural and biomedical polymer with appropriate and improvable mechanical properties. Making a composite with a bioceramicas reinforcement is a general strategy to prepare a scaffold for hard tissue engineering applications. In the present study, SF was separately combined with titanium dioxide (TiO2) and fluoridated titanium dioxide nanoparticles (TiO2-F) as bioceramic reinforcements for bone tissue engineering purposes. At the first step, SF was extracted from Bombyx mori cocoons. Then,...
The effect of nano-TiO2 additions on the densification and mechanical properties of SiC-matrix composite
, Article Ceramics International ; Volume 46, Issue 5 , April , 2020 , Pages 6477-6483 ; Yaghobizadeh, O ; Baharvandi, H. R ; Alipour Shahraki, A ; Mohammadi, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
This research studied the effect of adding TiO2 nanoparticles along with Al2O3 and Y2O3 additives on the physical and mechanical properties of a SiC-matrix composite. The samples were fabricated through a pressureless process at 1900 °C. The results showed that the addition of TiO2 nanoparticles up to 4.5 wt% inhibited the excessive growth of SiC grains. According to the investigations, the microstructure and final properties of composites were affected by density, synthesized phases as well as their distribution in the matrix, and grain size. The highest density, Young's modulus, hardness, indentation fracture resistance, and flexural strength, alongside with the lowest brittleness index...
In situ synthesized TiO2-polyurethane nanocomposite for bypass graft application: In vitro endothelialization and degradation
, Article Materials Science and Engineering C ; Volume 114 , May , 2020 ; Bagheri, R ; Pourjavadi, A ; Ghanbari, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The in vitro endothelial response of human umbilical vein endothelial cells was investigated on a poly (caprolactone)-based polyurethane surface vs an in situ TiO2-polyurethane nanocomposite surface, which has been produced as scaffolds for artificial vascular graft. The in situ synthesis of TiO2 nanoparticles in polyurethane provided surface properties that facilitated cellular adhesion, cell sensing, cell probing and especially cell migration. Cells on the nanocomposite surface have elongated morphology and were able to produce more extracellular matrix. All of these advantages led to an increase in the rate of endothelialization of the nanocomposite scaffold surface vs pure polyurethane....
Carbonaceous supports decorated with Pt–TiO2 nanoparticles using electrostatic self-assembly method as a highly visible-light active photocatalyst for CO2 photoreduction
, Article Renewable Energy ; Volume 145 , January , 2020 , Pages 1862-1869 ; Khorasheh, F ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Supported Pt–TiO₂ photocatalysts on carbonaceous supports were synthesized by the electrostatic self-assembly method to study CO₂ photoreduction to produce CH₄. Catalytic activities of the prepared photocatalysts were correlated with the particle size and dispersion of the active metal, which in turn depended on the type of carbonaceous support used, varying in the order of multi-walled carbon nanotubes (MWCNT) > Single-walled carbon nanotubes (SWCNT) > reduced graphene oxide > activated carbon. Generally, all catalysts were highly photoresistant with less than 5% loss of activity in terms of CH₄ yield. Pt–TiO₂/multi-walled carbon nanotubes exhibited better catalytic activity compared with...
Sequential RTV/(TiO2/SiO2) nanocomposite deposition for suppressing the leakage current in silicone rubber insulators
, Article Applied Physics A: Materials Science and Processing ; Volume 126, Issue 5 , 2020 ; Mohammadi, M ; Shayegani Akmal, A. A ; Samadpour, M ; dehghani, M ; Parvazian, E ; Sharif University of Technology
Springer
2020
Abstract
The sequential deposition method is introduced for suppressing the leakage current in silicone rubber insulators. Room temperature vulcanizing silicone and TiO2/silica nanocomposites are sequentially deposited on silicone insulators surface. TEM results showed that TiO2 nanoparticles size is about 20–30 nm, and the structural study revealed their anatase crystalline structure. Silica nanoparticles are deposited on the surface of insulators by spray deposition. The contact angle was enhanced from 104° to 149° after nanoparticles deposition, which confirms the hydrophobicity improvement. Results show that leakage current for nanocomposite samples in a contaminated environment reduced to about...
Efficiency improvement of solar stills through wettability alteration of the condensation surface: An experimental study
, Article Applied Energy ; Volume 268 , 2020 ; Soltani Goharrizi, A ; Ayatollahi, S ; Feilizadeh, M ; Dashti, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The condensation process is of great importance in many heat transfer devices in which a large amount of energy must be transferred. Furthermore, condensation is a crucial part of energy conversion and affects the energy efficiency of thermal desalination plants and solar stills. During the condensation process in solar stills, an essential part of the energy is transferred through the condensation surface to produce fresh water. Therefore, the condensation surface plays a significant role in the working efficiency of solar stills. The wettability of the condensation surface influences the condensation mechanism, which, in turn, affects the efficiency of solar stills. This study aims to...
Enhanced TiO2broadband photocatalytic activity based on very small upconversion nanosystems
, Article Journal of Physical Chemistry C ; Volume 125, Issue 25 , 2021 , Pages 13788-13801 ; 19327447 (ISSN) ; Madaah Hosseini, H. R ; Mohajerani, E ; Pedroni, M ; Taheri Ghahrizjani, R ; Sharif University of Technology
American Chemical Society
2021
Abstract
Efficient sunlight harvesting is of great significance for environmental remediation through photocatalysis. Herein, very small (20 nm) upconverter SrF2:Yb,Tm@CaF2:Yb@Fluorine-doped TiO2heteronanoparticles (denoted as UCNPs@TiO2) with strong UV-blue emission and broadband photocatalytic performance were prepared via a facile three-step hydrothermal method for the first time. The SrF2:Yb,Tm upconverter nanoparticles (NPs) were produced as the light-emitting core, epitaxially grown CaF2:Yb as the middle shell to enhance the upconversion luminescence output and TiO2as the photocatalyst outermost layer. Superior photocatalytic functioning of UCNPs@TiO2was affirmed through methylene blue (MB)...
Simulation of wellbore drilling energy saving of nanofluids using an experimental taylor–couette flow system
, Article Journal of Petroleum Exploration and Production ; Volume 11, Issue 7 , 2021 , Pages 2963-2979 ; 21900558 (ISSN) ; Sedaghat, A ; Misbah, B ; Sabati, M ; Vaidyan, K ; Mostafaeipour, A ; Hosseini Dehshiri, S. S ; Almutairi, K ; Issakhov, A ; Oloomi, S. A. A ; Malayer, M. A ; Arockia Dhanraj, J ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
Power consumption of wellbore drilling in oil and gas exploitations count for 40% of total costs, hence power saving of WBM (water-based mud) by adding different concentrations of Al2O3, TiO2 and SiO2 nanoparticles is investigated here. A high-speed Taylor–Couette system (TCS) was devised to operate at speeds 0–1600 RPM to simulate power consumption of wellbore drilling using nanofluids in laminar to turbulent flow conditions. The TCS control unit uses several sensors to record current, voltage and rotational speed and Arduino microprocessors to process outputs including rheological properties and power consumption. Total power consumption of the TCS was correlated with a second-order...