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Tire tread performance of silica-filled SBR/BR rubber composites incorporated with nanodiamond and nanodiamond/nano-SiO2 hybrid nanoparticle
, Article Diamond and Related Materials ; Volume 126 , 2022 ; 09259635 (ISSN) ; Momenilandi, M ; Shojaei, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In the present research, the influence of nanodiamond (ND) and a physical hybrid of ND and fumed nano-SiO2 were investigated on the performance of a typical tire tread compound. The styrene-butadiene rubber (SBR) and cis-butadiene rubber (BR) blend filled with a commercial grade highly dispersive silica at 70 phr loading were used as typical tire tread compound. ND was substituted partially with silica at two different concentrations of 5 and 10phr. Meanwhile, 5 phr of ND/nano-SiO2 hybrids with the weight ratio of 2.5/2.5 and 1/4 were substituted with silica. ND-Filled compounds exhibit increased scorch and cure time compared to controls. Improvement in different characteristics of the...
Application of hybrid nanofluids in a novel combined photovoltaic/thermal and solar collector system
, Article Solar Energy ; Volume 239 , 2022 , Pages 102-116 ; 0038092X (ISSN) ; Salari, A ; Ma, T ; Lu, H ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Because of the low outflow temperature of the conventional photovoltaic thermal systems and lack of electrical production of the solar thermal collectors, a novel combined system is proposed to solve the two mentioned drawbacks. This novel system is achieved by connecting a photovoltaic thermal unit to a solar thermal collector in series. To increase the overall performance of this novel combined system, different hybrid nanofluids include (1) multiwall carbon nanotube-aluminum oxide (2) multiwall carbon nanotube-silicon carbide (3) graphene-aluminum oxide, and (4) graphene-silicon carbide are compared. The investigation is performed based on the three-dimensional simulation, 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...
Electro-optical properties of APS and APhS linkers on silicon thin film: A DFT study
, Article Applied Surface Science ; Volume 605 , 2022 ; 01694332 (ISSN) ; Darvish, G ; Faez, R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
APS (3-Aminopropyl) trimethoxysilane) and APhS (p-Aminophenyl) trimethoxysilane) are the most commonly used linkers on a silicon surface. We investigate the surface properties of the structures, including APS or APhS on a silicon substrate. The studied structures consist of APS or APhS linkers with one, two, or three bonds with a substrate, which is a thin layer of Si with crystal orientation 〈1 0 0〉 or 〈1 1 1〉. Using a first-principles study based on density functional theory (DFT), we investigated the electronic and optical properties of the silicon-linker interface, such as interface states, orbital location, dielectric function, and photon absorption. The effects of linker type, number...
Evaluation of whisker alignment and anisotropic mechanical properties of ZK60 alloy reinforced with SiCw during KOBO extrusion method
, Article Journal of Manufacturing Processes ; Volume 84 , 2022 , Pages 344-356 ; 15266125 (ISSN) ; Wang, Y ; Yarigarravesh, M ; Tayyebi, M ; Tayebi, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In current study, microstructure and high-temperature mechanical properties of ZK60 magnesium alloy reinforced by SiC whiskers were investigated after casting, the KOBO extrusion and aging processes. For this purpose, ZK60/SiCw composite specimens were prepared by stir casting technique. In order to achieve a laminar structure and improve the strength, the samples were subjected to KOBO extrusion technique and precipitation hardening, resulting in improved strength and increased ductility. The former is due to grain refining and formation of precipitates in the microstructure, while the latter is attributed to grain refining and formation of laminar structure. To evaluate the strength of the...
Effect of heat treatment parameters on microstructure, defects, and properties of Al-16Si-6Cu automotive shift fork: quantitative evaluation perspective
, Article International Journal of Cast Metals Research ; Volume 35, Issue 1-3 , 2022 , Pages 60-72 ; 13640461 (ISSN) ; Abazari, M ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
The current study investigated the effect of heat treatment parameters, including solution treatment temperature (STT), time, and quench rate, on the microstructure, defects, and hardness of an Al-16Si-6Cu Shift fork die-cast alloy. The changes in primary silicon particle (PSP) features were examined quantitatively by optical microscopy, coupled with image analysis and SEM equipped with EDS. The biggest PSPs (27 ± 8 µm) and the highest area fraction (23%) were found in the sample solution treated at 470°C and cooled in the furnace. The hardness value increased in heat-treated samples slightly (140–148 BHN). A lower STT (420°C) and a lower ageing time (1 h) are suitable conditions for the...
Label-Free real-time detection of HBsAg using a QCM immunosensor
, Article Clinical Laboratory ; Volume 68, Issue 4 , 2022 , Pages 707-720 ; 14336510 (ISSN) ; Ghavidel, A ; Ahangari Cohan, R ; Hamidi Fard, M ; Khoobi, M ; Aghasadeghi, M ; Norouzian, D ; Sharif University of Technology
Verlag Klinisches Labor GmbH
2022
Abstract
Background: Hepatitis B virus surface antigen (HBsAg) is an important protein in both diagnosis and prevention of hepatitis B infection. In the current study, a piezoelectric immunosensor based on antibody-antigen interaction was designed to detect HBsAg. A quartz crystal microbalance system was employed to detect antibody-antigen interaction. Methods: At first, an oscillator was designed to measure the resonant frequency affected by the reactants using IC 74LVC1GX04. Antibody against HBsAg was immobilized on 10 MHz AT-cut quartz crystal. The surface modifications were monitored by atomic force microscopy (AFM) and contact angle measurements. Different concentrations of antibody were used...
Enhanced electromagnetic wave dissipation features of magnetic Ni microspheres by developing core-double shells structure
, Article Ceramics International ; Volume 48, Issue 1 , 2022 , Pages 446-454 ; 02728842 (ISSN) ; Mahariq, I ; Tran, N ; Mahmoud, M. Z ; Akhtar, M. N ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Readily oxidization of magnetic particles is a common drawback of these type of materials which reduce their electromagnetic wave dissipation performance. In this study, the magnetic core-double shells structured (Ni/SiO2/Polyaniline) composite has been developed for protection of the core from oxidation and in consequent improvement the complex permittivity. Solvothermal and in-situ polymerization methods were utilized for decorating Ni micro-particles with SiO2 and conductive polyaniline polymer respectively. All physico-chemical, magnetic and electromagnetic features were evaluated via XRD, FTIR, XPS, FESEM, VSM and VNA analysis. The double shells composite possesses significant...
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...
Investigation into the effect of substrate material on microstructure and optical properties of thin films deposited via magnetron sputtering technique
, Article Ceramics International ; 2021 ; 02728842 (ISSN) ; Nemati, A ; Hadi, I ; Mirdamadi, Sh ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
This study aims at investigating the effect of the substrate material on growth mechanism and also microstructure of Ta2O5 thin films. For this purpose, atomic force microscopy, scanning electron microscopy, and interferometry analyses were implemented to reveal the influence of silicon wafer and amorphous BK7 glass substrates on the nucleation and growth mechanisms of Ta2O5 thin films deposited via the radio frequency magnetron sputtering technique. Results indicated that those films with finer morphologies had relatively higher nucleation densities. Compared with BK7 glass substrate, crystals formed on the silicon wafer were shown to be finer and had lower mean areas in more nucleation...
A theory for coupled lithium insertion and viscoplastic flow in amorphous anode materials for Li-ion batteries
, Article Mechanics of Materials ; Volume 152 , 2021 ; 01676636 (ISSN) ; Arghavani, J ; Naghdabadi, R ; Brassart, L ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Amorphous lithium metal alloys (LixM, with M=Si, Ge, Sn, …) are attractive anode materials for lithium-ion batteries owing to their high energy-storage capacity and safety characteristics. However, repeated insertion of lithium often leads to chemo-mechanical degradation of the alloy, which can severely reduce the battery capacity and cycle life. Better understanding of the chemo-mechanical response of lithium alloys is needed to guide the design of damage-resistant anode microstructures. In this work, we propose a constitutive theory that couples large, viscoplastic deformations to the insertion and extraction of lithium in amorphous electrode materials. The theory relies on the concept of...
Engineering of metallic nanorod-based hyperbolic metamaterials for broadband applications operating in the infrared regime
, Article Applied Nanoscience (Switzerland) ; Volume 11, Issue 1 , 2021 , Pages 229-240 ; 21905509 (ISSN) ; Farmani, A ; Raza, M ; Niaz Akhtar, M ; Hussain, A ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Metamaterials are manmade structures that have attained considerable attention over the past 2 decades in the modern fields like cloaking, sensing, and imaging owing to their ability to harness electromagnetic fields. In this regard, we have inspected the dielectric properties of the hyperbolic metamaterials (HMM) made of metallic nanorods and dielectric medium at the infrared wavelength regime. The periodically arranged subwavelength-sized metallic nanorods embedded in the silicon dioxide (SiO 2) substrate glass. The spacing between two adjacent nanorods is of subwavelength in size. Furthermore, effective permittivity of the metamaterial has been analyzed by employing the Maxwell Garnett...
On the physical layer security of the cooperative rate-splitting-aided downlink in UAV networks
, Article IEEE Transactions on Information Forensics and Security ; Volume 16 , 2021 , Pages 5018-5033 ; 15566013 (ISSN) ; Letafati, M ; Moradikia, M ; Abdelhadi, A ; Behroozi, H ; Hanzo, L ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Unmanned Aerial Vehicles (UAVs) have found compelling applications in intelligent logistics, search and rescue as well as in air-borne Base Station (BS). However, their communications are prone to both channel errors and eavesdropping. Hence, we investigate the max-min secrecy fairness of UAV-aided cellular networks, in which Cooperative Rate-Splitting (CRS) aided downlink transmissions are employed by each multi-antenna UAV Base Station (UAV-BS) to safeguard the downlink of a two-user Multi-Input Single-Output (MISO) system against an external multi-antenna Eavesdropper ( Eve ). Realistically, only Imperfect Channel State Information (ICSI) is assumed to be available at the transmitter....
Electrospun chitosan/polyvinyl alcohol nanocomposite holding polyaniline/silica hybrid nanostructures: An efficient adsorbent of dye from aqueous solutions
, Article Journal of Molecular Liquids ; Volume 331 , 2021 ; 01677322 (ISSN) ; Tati, A ; Ahmadipouya, S ; Haddadi, S. A ; Arjmand, M ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In this work, the addition of a novel polyaniline (PANI)/silica (SiO2) nanostructure (PSn) in chitosan/polyvinyl alcohol nanofibers (CP) was evaluated to enhance the dye removal capacity of CP. Fourier transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDS) results confirmed the chemical grafting of SiO2 on PANI nanoparticles. Brunauer-Emmett-Teller (BET) results showed a specific surface area of 61 m2 g−1 for the PSn filled CP nanofiber (CP-PSn). FE-SEM and EDS-elemental mapping results showed the uniform dispersibility of PSn in CP nanofibers. After the addition of PSn into CP, the adsorption capacity of...
Magnetoelastic coupling enabled tunability of magnon spin current generation in two-dimensional antiferromagnets
, Article Physical Review B ; Volume 104, Issue 18 , 2021 ; 24699950 (ISSN) ; Hamdi, M ; Park, S ; Khavasi, A ; Mohseni, S. M ; Sadeghi, A ; Sharif University of Technology
American Physical Society
2021
Abstract
We theoretically investigate the magnetoelastic coupling (MEC) and its effect on magnon transport in two-dimensional antiferromagnets with a honeycomb lattice. MEC coefficients along with magnetic exchange parameters and spring constants are computed for monolayers of transition-metal trichalcogenides with Néel magnetic order (MnPS3 and VPS3) and zigzag order (CrSiTe3, NiPS3, and NiPSe3) by ab initio calculations. Using these parameters, we predict that the spin-Nernst coefficient is significantly enhanced due to magnetoelastic coupling. Our study shows that although Dzyaloshinskii-Moriya interaction can produce spin-Nernst effect in these materials, other mechanisms such as magnon-phonon...
Symmetry enhanced spin-Nernst effect in honeycomb antiferromagnetic transition metal trichalcogenide monolayers
, Article Physical Review B ; Volume 103, Issue 1 , 2021 ; 24699950 (ISSN) ; Hamdi, M ; Haddadi, F ; Khavasi, A ; Sadeghi, A ; Mohseni, S. M ; Sharif University of Technology
American Physical Society
2021
Abstract
We investigate systematically the spin-Nernst effect in Néel and zigzag ordered honeycomb antiferromagnets. Monolayers of transition-metal trichalcogenides, MnPSe3, MnPS3, and VPS3 show an antiferromagnetic Néel order while CrSiTe3, NiPS3, and NiPSe3 show an antiferromagnetic zigzag order. We extract the exchange and Dzyaloshinskii-Moriya interaction parameters from ab initio calculations. Using these parameters, we predict that the spin-Nernst coefficient is at least two orders of magnitude larger in zigzag compared to the Néel ordered antiferromagnets. We find that this enhancement relies on the large band splitting due to the symmetry of magnetic configuration in the zigzag order. Our...
Twisted-shape selection of self-assembled Si 〈100〉 nanobelts and nanowires
, Article Journal of Physics D: Applied Physics ; Volume 54, Issue 25 , 2021 ; 00223727 (ISSN) ; Nejat Pishkenari, H ; Zohoor, H ; Sharif University of Technology
IOP Publishing Ltd
2021
Abstract
This letter discusses the surface-reconstruction-induced self-twisting behavior of Si100 nanobelts and nanowires (NWs) with rectangular cross section. Giving a thorough physical interpretation, we explain the reason behind this phenomenon and present a continuum-based model. It is revealed that these structures can self-assemble into both right- and left-handed helicoids depending on their crystal arrangements. More specifically, for NWs with the same number of layers in each of their cross sections directions, two distinct values of torsion angle are possible for each of right- and left-handed twisted morphologies. In conclusion, four modes of torsion can be observed in Si100 NWs....
Anodizing behavior and electrochemical evaluation of accumulative roll bonded Al and Al-SiC composite
, Article Surface and Coatings Technology ; Volume 408 , 2021 ; 02578972 (ISSN) ; Alishavandi, M ; Paydar, M. H ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Accumulative roll bonded (ARBed) AA1050 and Al-2 vol% SiCp (AMC) samples were anodized in an H2SO4 electrolyte to improve corrosion resistance. The SEM images revealed that the anodic oxide's morphology is significantly dependent on the microstructure of the ARBed bare samples, owing to high internal energy that accelerates Al consumption during anodizing process. Potentiodynamic polarization measurements and EIS evaluation showed that anodic oxide improves the corrosion resistance of both ARBed AA and AMC samples; however, the electrochemical behavior of the processed samples changed due to the formation of a complex oxide structure comprising of twisted pore channels and attack routes. ©...
Developing a new superhydrophilic and superoleophobic poly(4-(1-vinyl-1H-imidazol-3-ium-3-yl) butane-1-sulfonate): vinyl imidazole@Perfluorooctanoic acid@SiO2 coated stainless steel mesh for highly efficient, stable, and durable oil/water separation
, Article Journal of Coatings Technology and Research ; Volume 18, Issue 2 , 2021 , Pages 511-521 ; 15470091 (ISSN) ; Siavash Moakhar, R ; Amirpoor, S ; Azad, M ; Dolati, A ; Sharif University of Technology
Springer
2021
Abstract
The design and development of efficient approaches for water–oil separation have had widespread interest. Most previously introduced techniques and materials used for development of the successful separation of oily wastewater could not answer all the desired demands, such as being efficient and environmentally and economically friendly. Therefore, in seeking a novel method capable of answering these expectations, surfaces with special wettability were introduced. A novel, reusable, and recyclable superhydrophilic and superoleophobic poly(Vsim-Vim)@PFOA@SiO2 nanocomposite-coated stainless steel mesh was synthesized through a facile preparation process. Since the most important factors of...
Optimization of nano HA-SiC coating on AISI 316L medical grade stainless steel via electrophoretic deposition
, Article Materials Letters ; Volume 285 , 2021 ; 0167577X (ISSN) ; Ahangari, M ; Johar, M. H ; Allahkaram, S. R ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Biocompatible nanostructured coating plays an important role in enhancement of osseointegration ability of metallic implants. This study sets out to obtain optimized SiC concentration in Hydroxyapatite (HA) coating on AISI 316L stainless steel alloy through electrophoretic deposition method. Effect of SiC concentrations (1, 2, and 3%.wt) on the morphology, corrosion behaviour, and mechanical properties of the HA coating is investigated. Results show that SiC could obstruct the formation and growth of micro cracks in the HA coating where HA-3%SiC is considered as a crack free coating. Electrochemical tests reveal that SiC has improved the corrosion resistance of HA coating, and HA-3%SiC...