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Improving bactericidal performance of implant composite coatings by synergism between Melittin and tetracycline
, Article Journal of Materials Science: Materials in Medicine ; Volume 33, Issue 6 , 2022 ; 09574530 (ISSN) ; Ghorbani, M ; Pooshang Bagheri, K ; Shokrgozar, M. A ; Sharif University of Technology
Springer
2022
Abstract
Methicillin resistance Staphylococcus aureus bacteria (MRSA) are serious hazards of bone implants. The present study was aimed to use the potential synergistic effects of Melittin and tetracycline to prevent MRSA associated bone implant infection. Chitosan/bioactive glass nanoparticles/tetracycline composite coatings were deposited on hydrothermally etched titanium substrate. Melittin was then coated on composite coatings by drop casting method. The surfaces were analyzed by FTIR, XRD, and SEM instruments. Tetracycline in coatings revealed multifunctional behaviors include bone regeneration and antibacterial activity. Releasing ALP enzyme from MC3T3 cells increased by tetracycline, so it is...
Ag-incorporated biodegradable Mg alloys
, Article Materialia ; Volume 23 , 2022 ; 25891529 (ISSN) ; Alizadeh, R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Biodegradable magnesium implants possess excellent mechanical properties and biocompatibility, which make them suitable candidates to be employed as temporary structures for the bone regeneration purposes. However, there are still important challenges which limit their extensive use in biomedical applications, where the most important ones include implant-associated infection, rapid degradation rate and the need for improved mechanical properties. Silver, which is a strong antimicrobial agent, has been extensively used for improving the mentioned challenges in biodegradable Mg alloys either as alloying element or incorporation in the protective coating. Ag addition has been reported to have...
Enhancing Seebeck coefficient and electrical conductivity of polyaniline/carbon nanotube–coated thermoelectric fabric
, Article Journal of Industrial Textiles ; Volume 51, Issue 2_suppl , 2022 , Pages 3297S-3308S ; 15280837 (ISSN) ; Ramazani Saadatabadi, A ; Pourjahanbakhsh, M ; Siadati, M. H ; Sharif University of Technology
SAGE Publications Ltd
2022
Abstract
In this work, flexible thermoelectric fabrics, polyester/yarn fabrics coated with polyaniline/carbon nanotube (PANI/CNT) nanocomposite, were fabricated by sequential processing: (I) polyaniline/carbon nanotube nanocomposites preparation by a one-step in-situ polymerization and (II) dip coating of a mixture solution of CNT-doped PANI on a polyester/yarn fabric. Nanocomposites were synthesized with various CNT content (0.5, 2.5, 5, and 10 wt%) and characterized using different methods. The Seebeck coefficient and electrical conductivity measurements were used to determine their thermoelectric properties. The results revealed significant improvement in both electrical conductivity and the...
Tuning the wetting properties of SiO2-based nanofluids to create durable surfaces with special wettability for self-cleaning, anti-fouling, and oil-water separation
, Article Industrial and Engineering Chemistry Research ; Volume 61, Issue 23 , 2022 , Pages 8005-8019 ; 08885885 (ISSN) ; Ghazanfari, M. H ; Molaei Dehkordi, A ; Sharif University of Technology
American Chemical Society
2022
Abstract
Surfaces with special wettability have aroused lots of attention due to their broad applications in many fields. In this work, we systematically report selective and various fabrications of nanofluids based on readily available materials such as SiO2 nanoparticles and polydimethylsiloxane to create superhydrophobic, superoleophobic, superhydrophilic/superoleophobic, and underwater superoleophobic coatings. The efficiency of prepared coatings is investigated on mineral rock plates as porous substrates via the straightforward and cost-effective solution-immersion technique. The static water contact angle of 170°, effortless bouncing of water droplets, and self-cleaning property with a near...
Application of numerical simulation to solid phase-microextraction for decreasing of extraction time of pyrene and phthalate esters on solid coatings
, Article Journal of Chromatography A ; Volume 1673 , 2022 ; 00219673 (ISSN) ; Jamshidian, M ; Habibi, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Reynolds-Averaged Navier-Stokes (RANS) approach with the k-ε closure model is employed for the first time to simulate direct Solid-Phase Micro-Extraction (SPME) computationally. Simulations are performed by using COMSOL Multiphysics in order to examine methods to decrease the extraction time. Experiments are also conducted to support data obtained from the numerical framework. Di-n-Butyl Phthalate (DNBP) and etched steel wire are chosen as the analyte and the adsorbent, respectively. Stirring rate, fiber's location, stirrer magnet's size, and the method of sample rotation are examined to decrease the extraction time. In addition, the effects of adding a baffle to the vial and implementing a...
Biodegradation behavior of polymethyl methacrylate−bioactive glass 45S5 composite coated magnesium in simulated body fluid
, Article Transactions of Nonferrous Metals Society of China (English Edition) ; Volume 32, Issue 7 , 2022 , Pages 2216-2228 ; 10036326 (ISSN) ; Jafari, H ; Pishbin, F ; Mohammadi, R ; Simchi, A ; Sharif University of Technology
Nonferrous Metals Society of China
2022
Abstract
The biodegradation behavior of Mg, coated by polymethyl methacrylate as well as polymethyl methacrylate (PMMA)−bioactive glass (BG) composite was investigated. Electrophoretic deposition and dip coating techniques were adopted to prepare composite coating using a suspension of different percentages of the above two chemical materials. The deposited coatings were characterized using SEM, EDS, FTIR, and water contact angle measurements. Biodegradation behavior study of the coated Mg was performed using linear polarization, impedance spectroscopy, and immersion tests in simulated body fluid. The compact and homogeneous composite coating was developed as evidenced by electron microscopy results....
Implementation of binder-free SnO2 NWs@C electrode and LiTFSI-based electrolyte for high-performance lithium-ion battery
, Article Journal of Physics D: Applied Physics ; Volume 56, Issue 1 , 2022 ; 00223727 (ISSN) ; Habibi, A ; Sanaee, Z ; Ghasemi, S ; Mohajerzadeh, S ; Sharif University of Technology
Institute of Physics
2022
Abstract
This study has investigated the effect of carbon coating on the electrochemical performance of SnO2 Nanowires (NWs) as an electrode along with a bis (trifluoromethane) sulfonimide lithium (LiTFSI)-based electrolyte in a lithium-ion battery (LIB). The vapor-liquid-solid approach has been used to grow SnO2 NWs on the stainless steel mesh current collector. The obtained results have demonstrated that the utilization of the LiTFSI-based electrolyte improved the battery performance with the SnO2 NWs electrode over the LiPF6-based electrolyte. This may be due to the formation of a stable and thin solid electrolyte interphase layer. Since bare SnO2 NWs exhibit inferior cycling stability due to...
Niosomal formulation for antibacterial applications
, Article Journal of Drug Targeting ; Volume 30, Issue 5 , 2022 , Pages 476-493 ; 1061186X (ISSN) ; Gharehchelou, B ; Haghighi Poodeh, S ; Jamshidifar, E ; Karimifard, S ; Farasati Far, B ; Akbarzadeh, I ; Seifalian, A ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Infection is a disease that is mainly caused by different Gram-negative and Gram-positive bacteria. Treatment of infections requires a considerable amount of antibiotics, which can cause serious damage to the patient's body. Delivering the antibiotic only to the site of infection can prevent these destructive effects, such as the destruction of the normal intestinal flora. The drug delivery system through carriers will take antibiotics into a part of the body involved in the disease. Niosome nanoparticles, which have been made from non-ionic surfactants, have been emerging as ideal drug/antibiotics delivery vehicles. Recently, niosome formulations have been targeted to reduce toxicity and...
Magnetic, thermally stable, and superhydrophobic polyurethane sponge: A high efficient adsorbent for separation of the marine oil spill pollution
, Article Chemosphere ; Volume 287 , 2022 ; 00456535 (ISSN) ; Pourjavadi, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Herein, we demonstrated a facile method for the fabrication of magnetic and superhydrophobic polyurethane sponge with water contact angle of 159° as an adsorbent for cleanup the marine oil spill pollution. For this aim, a polyurethane sponge was coated with carbon black (CB), hexagonal boron nitride (h-BN)@Fe3O4, and acrylic resin and then characterized by different techniques. Owing to the chemical and thermal stability of h-BN and CB, the modified sponge was stable under corrosive conditions (pH = 1–14 and salt solutions) and at different temperatures (−12 °C–105 °C). In addition to common oils and organic solvents, we also used the real spilled oils containing monoaromatics and...
Numerical study on the post-earthquake fire behavior of intermediate steel moment frames
, Article Earthquake and Structures ; Volume 22, Issue 2 , 2022 , Pages 137-145 ; 20927614 (ISSN) ; Kazemia, M. T ; Sharif University of Technology
Techno-Press
2022
Abstract
As steel is highly sensitive to temperature variations, fire exposure is more destructive in the case of steel structures in comparison to the concrete ones. The performance of an intermediate three-story steel moment frame with 4 spans was studied under the service load, thermal load and post-earthquake fire in this paper. Also, the effects of passive fire-protection materials such as ordinary cement-based and fire-retardant coatings were investigated. To model and analyze the structure; Abaqus software is utilized. In order to apply the earthquake effect, the push-over analysis method is employed. Changes in the stories deflection, endurance time and growth of nonlinear regions due to...
Development of HAp/GO/Ag coating on 316 LVM implant for medical applications
, Article Journal of the Mechanical Behavior of Biomedical Materials ; Volume 126 , 2022 ; 17516161 (ISSN) ; Izanloo, S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In this study, antibacterial activity, biocompatibility, and corrosion resistance of 316 LVM implants were improved using the development of HAp/GO/Ag nanocomposite coatings by the dip-coating method. The XRD and FTIR results confirmed the synthesis of HAp/GO/Ag nanocomposites. HAp/Ag nanoparticles (68 nm) bound to epoxy, hydroxyl, and carboxyl functional groups on GO sheets (size of GO sheets varies from 255 to 1480 nm) by electrostatic interaction. FESEM images showed that HAp/GO/Ag coatings had higher density and fewer micro-cracks than pure HAp coatings. In addition, HAp/GO/Ag coatings showed optimized nano-hardness (4.5 GPa) and elasticity modulus (123 GPa). The results of...
Detection and analysis of corrosion and contact resistance faults of tin and crn coatings on 410 stainless steel as bipolar plates in PEM fuel cells
, Article Sensors ; Volume 22, Issue 3 , 2022 ; 14248220 (ISSN) ; Kashyzadeh, K. R ; Borjali, A ; Ivanov, A ; Jafarnode, M ; Gan, T. H ; Wang, B ; Chizari, M ; Sharif University of Technology
MDPI
2022
Abstract
Bipolar Plates (BPPs) are the most crucial component of the Polymer Electrolyte Membrane (PEM) fuel cell system. To improve fuel cell stack performance and lifetime, corrosion resistance and Interfacial Contact Resistance (ICR) enhancement are two essential factors for metallic BPPs. One of the most effective methods to achieve this purpose is adding a thin solid film of conductive coating on the surfaces of these plates. In the present study, 410 Stainless Steel (SS) was selected as a metallic bipolar plate. The coating process was performed using titanium nitride and chromium nitride by the Cathodic Arc Evaporation (CAE) method. The main focus of this study was to select the best coating...
Studies of Ponceau 4R food colorant and zinc oxide nanoparticles containing it interactions with DNA and evaluation of their antimicrobial activity
, Article Journal of Food Processing and Preservation ; Volume 46, Issue 2 , 2022 ; 01458892 (ISSN) ; Shahabadi, N ; Mahmoudi Hashemi, M ; Meibodi, F. S ; Mirjafari, Z ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
The current study describes design and synthesis of silica-coated zinc oxide nanoparticles containing Ponceau 4R food colorant (named as ZnO@SiO2@APTMS/P4R). The interactions of Ponceau 4R and ZnO@SiO2@APTMS/P4R with calf thymus-DNA were investigated It should be noted that the competitive binding experiment revealed that both Ponceau 4R and ZnO@SiO2@APTMS/P4R could release Hoechst 33258. As inferred from the results the binding of the Ponceau 4R and ZnO@SiO2@APTMS/P4R with DNA were surface binding, mainly due to groove binding. Furthermore, antibacterial properties of ZnO, Ponceau 4R and ZnO@SiO2@APTMS/P4R samples against gram-positive bacteria and gram-negative bacteria were examined and...
Epoxy nanocomposite coating based on calcium zinc phosphate with dual active/barrier corrosion mitigation properties
, Article Progress in Organic Coatings ; Volume 163 , 2022 ; 03009440 (ISSN) ; Haddadi, S. A ; Motlagh, A. L ; Ghaderi, M ; Ramezanzadeh, B ; Mahdavian, M ; Arjmand, M ; Jalili, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In this paper, a high-performance epoxy nanocomposite with dual active/barrier protection ability based on calcium zinc phosphate (CZP) nanopigment was fabricated. Then chemistry, morphology, and anti-corrosion ability of the commercial zinc phosphate (ZP) and CZP pigments were studied. By electrochemical techniques, the inhibition potency of the CZP nanopigment was examined in a NaCl solution on mild steel (MS) substance and compared with that of ZP. Results revealed a higher corrosion inhibition degree of the CZP compared to the ZP. The growth of a protective layer on the metal coupons exposed to the CZP extract was illustrated by X-ray photoelectron spectroscopy (XPS), field emission...
Smart protection of surfaces during day-night by a novel composite self-cleaning coating with catalytic memory
, Article Journal of Environmental Chemical Engineering ; Volume 10, Issue 1 , 2022 ; 22133437 (ISSN) ; Nguyen, D. T ; Sakar, M ; Lucotti, A ; Asa, M ; Kaveh, R ; Diamanti, M. V ; Pedeferri, M ; Do, T.-O ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
For the first time this work reports a new idea to develop a round-the-clock self-cleaning coating which was successfully applied to preserve cultural heritage and modern artifacts under sunlight illumination and at night. To fabricate this structure, namely, H2:TiO2/WO3@Pt, soft templating and hydrogen treatment approaches were selected to enhance the performance of TiO2/WO3 photocatalyst, together with the addition of Pt plasmonic nanoparticles. The coating can be photochemically charged in the presence of sacrificial electron donors and keep its stability, benefiting from the remained electrons stock for over 10 h to clean the surface from aggressive pollution also at night, in absence of...
Aperiodic perforated graphene in optical nanocavity absorbers
, Article Materials Science and Engineering B: Solid-State Materials for Advanced Technology ; Volume 276 , 2022 ; 09215107 (ISSN) ; Akhavan, O ; Salami, P ; Yousefi, L ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Aperiodic perforated graphene layers were synthesized and used in fabrication of optical nanocavity absorbers. Chemical vapor deposition-grown graphene (Gr) layers were exposed to oxygen plasma etching to obtain the perforated graphene (pGr). The fabricated pGr/SiO2 (68 nm)/Ag (150 nm) nanocavity could present significant higher optical absorption, especially at around 530 nm wavelength region, as compared to a benchmark Gr/SiO2 (68 nm)/Ag (150 nm) sample. The effect of pore size of the pGr layer on the absorption property of the nanocavity has been studied by both experimental and numerical methods. The dependence of the absorption property of the nanocavity on the incident angles of...
Effect of crystallographic texture and twinning on the corrosion behavior of Mg alloys: A review
, Article Journal of Magnesium and Alloys ; Volume 10, Issue 2 , 2022 , Pages 313-325 ; 22139567 (ISSN) ; Alizadeh, R ; Langdon, T. G ; Sharif University of Technology
National Engg. Reaserch Center for Magnesium Alloys
2022
Abstract
Magnesium and its alloys have gained significant popularity due to their light weight and their potential for use as bioresorbable materials. However, their application is limited in practice due to their relatively poor corrosion resistance. Several methods are available for improving the corrosion resistance of Mg alloys for bio-applications such as using different coatings, alloying, and modifying the microstructural parameters such as the grain size and the crystallographic texture. This review provides a comprehensive summary of the effects of crystallographic texture and twinning, as one of the most important deformation mechanisms of Mg and Mg alloys, on the corrosion behavior....
A modified Jarzynski free-energy estimator to eliminate non-conservative forces and its application in nanoparticle-membrane interactions
, Article Physical Chemistry Chemical Physics ; Volume 24, Issue 6 , 2022 , Pages 3647-3654 ; 14639076 (ISSN) ; Lund, M ; Ejtehadi, M. R ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
Computational methods to understand interactions in bio-complex systems are however limited to time-scales typically much shorter than in Nature. For example, on the nanoscale level, interactions between nanoparticles (NPs)/molecules/peptides and membranes are central in complex biomolecular processes such as membrane-coated NPs or cellular uptake. This can be remedied by the application of e.g. Jarzynski's equality where thermodynamic properties are extracted from non-equilibrium simulations. Although, the out of equilibrium work leads to non-conservative forces. We here propose a correction Pair Forces method, that removes these forces. Our proposed method is based on the calculation of...
Kinetics of wettability alteration and droplet detachment from a solid surface by low-salinity: A lattice-Boltzmann method
, Article Fuel ; Volume 329 , 2022 ; 00162361 (ISSN) ; Zhan, Y ; Mahani, H ; Niasar, V ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The dynamics of droplet detachment from a surface is a fundamental topic studied in coating engineering, fluid mechanics, and subsurface engineering applications. This topic has direct relevance to wettability alteration using the modified ionic composition of water in contact with oil droplet, low salinity waterflooding (LSWF). Previous experimental studies of LSWF have shown a very long timescale in wettability alteration which cannot be explained using bulk diffusion coefficient. In the present study, we address both the time scale of detachment, as well as the impact of buoyancy and interfacial forces (referred to as Bond number) on droplet detachment by proposing an advanced...
Zn-rich (GaN)1−x(ZnO)x: a biomedical friend?
, Article New Journal of Chemistry ; Volume 45, Issue 8 , 2021 , Pages 4077-4089 ; 11440546 (ISSN) ; Rabiee, N ; Fatahi, Y ; Dinarvand, R ; Sharif University of Technology
Royal Society of Chemistry
2021
Abstract
A Zn-Rich (GaN)1−x(ZnO)xnanostructure was synthesized with the assistance of a high-gravity technique in order to reduce the reaction time and temperature. The synthesized inorganic nanomaterial has been applied in both drug and gene delivery systems, and as the first fully inorganic nanomaterial, it was investigated in a comprehensive cellular investigation as well. In order to increase the potential bioavailability, as well as the interactions with the pCRISPR, the nanomaterial was enriched with additional Zn ions. The nanomaterial and the final nanocarrier were characterized at each step before and after any biological analysisviaFESEM, AFM, TEM, FTIR and XRD. The polymer coated...