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    Effect of radially functionally graded materials on the primary resonances of large amplitude flexural vibration of in-extensional rotating shafts

    , Article Engineering Structures ; Volume 226 , 2021 ; 01410296 (ISSN) Jahangiri, M ; Bagheri, E ; Sharif University of Technology
    Elsevier Ltd  2021
    This paper analytically studies the effect of functionally graded materials (FGMs) on the primary resonances of large amplitude flexural vibration of in-extensional rotating shafts with nonlinear curvature as well as nonlinear inertia. The constituent material is assumed to vary along the radial direction according to a power-law gradation. The governing differential equations and the corresponding boundary conditions are derived employing the variational approach. Then, the Galerkin method and the multiple scales perturbation method are utilized to obtain the frequency–response equation. In a numerical case study, the effects of the power-law index on the steady-state responses and locus of... 

    Enhanced electrochemical performance and thermal stability of ZrO2- And rGO-ZrO2-Coated Li[Ni0.8Co0.1Mn0.1]O2Cathode material for Li-Ion batteries

    , Article ACS Applied Energy Materials ; Volume 4, Issue 1 , 2021 , Pages 934-945 ; 25740962 (ISSN) Khalili Azar, M ; Razmjoo Khollari, M. A ; Esmaeili, M ; Heidari, E ; Hosseini Hosseinabad, S. M ; Siavash Moakhar, R ; Dolati, A ; Ramakrishna, S ; Sharif University of Technology
    American Chemical Society  2021
    LiNi0.8Co0.1Mn0.1O2 (NCM811) has been considered as a promising cathode for Li-ion batteries (LIBs) due to its high electrochemical capacity and low cost; however, poor cycling stability is one of the main restricting factors in industrial applications of the NCM811 cathode material. Notably, the capacity fading and low structural stability of NCM811 are intensified at elevated temperatures. ZrO2- and composite rGO-ZrO2-coated NCM811 were fabricated by a facile wet chemical method and evaluated at 25 and 55 °C to overcome these impediments. The ZrO2 coating provides superior cycling and thermal stability and perfectly protects the cathode active material from deleterious side reactions, and... 

    Natural polymers decorated mof-mxene nanocarriers for co-delivery of doxorubicin/pCRISPR

    , Article ACS Applied Bio Materials ; Volume 4, Issue 6 , 2021 , Pages 5106-5121 ; 25766422 (ISSN) Rabiee, N ; Bagherzadeh, M ; Jouyandeh, M ; Zarrintaj, P ; Saeb, M. R ; Mozafari, M ; Shokouhimehr, M ; Varma, R. S ; Sharif University of Technology
    American Chemical Society  2021
    A one-pot and facile method with assistance of high gravity was applied for the synthesis of inorganic two-dimensional MOF-5 embedded MXene nanostructures. The innovative inorganic MXene/MOF-5 nanostructure was applied in co-delivery of drug and gene, and to increase its bioavailability and interaction with the pCRISPR, the nanomaterial was coated with alginate and chitosan. The polymer-coated nanosystems were fully characterized, and the sustained DOX delivery and comprehensive cytotoxicity studies were conducted on the HEK-293, PC12, HepG2, and HeLa cell lines, demonstrating acceptable and excellent cell viability at both very low (0.1 μg.mL-1) and high (10 μg·mL-1) concentrations. The... 

    Development of an active/barrier bi-functional anti-corrosion system based on the epoxy nanocomposite loaded with highly-coordinated functionalized zirconium-based nanoporous metal-organic framework (Zr-MOF)

    , Article Chemical Engineering Journal ; Volume 408 , 2021 ; 13858947 (ISSN) Ramezanzadeh, M ; Ramezanzadeh, B ; Bahlakeh, G ; Tati, A ; Mahdavian, M ; Sharif University of Technology
    Elsevier B.V  2021
    For the first time, the UIO-66, NH2-UIO, and NH2-UIO particles covalently functionalized by Glycidyl Methacrylate (GMA@NH2-UIO), were utilized as the novel functional anti-corrosive fillers. The functionality, high surface area, phase composition, excellent thermal properties as well as chemical stability of the Zr-MOFs were proved by FT-IR, BET, XRD, TGA, and water stability tests, respectively. The smart pH-sensitive controlled-release activity of the corrosion inhibitors (i.e., Zr ions and organic compounds) from the prepared Zr-MOFs was proved by the water stability test of the Zr-MOFs particles in the acidic (pH = 2), neutral (pH = 7.5), and alkaline (pH = 12) solutions containing 3.5... 

    Electrochemical performance and elevated temperature properties of the TiO2-Coated Li[Ni0.8Co0.1Mn0.1]O2 cathode material for high-safety li-ion batteries

    , Article ACS Applied Energy Materials ; Volume 4, Issue 5 , 2021 , Pages 5304-5315 ; 25740962 (ISSN) Razmjoo Khollari, M. A ; Azar, M. K ; Esmaeili, M ; Malekpour, N ; Hosseini Hosseinabad, S. M ; Moakhar, R. S ; Dolati, A ; Ramakrishna, S ; Sharif University of Technology
    American Chemical Society  2021
    Nowadays, the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode material has attracted great research interest due to its high energy density and less usage of costly raw materials. However, the high nickel content of NCM811 brings about an extremely unstable interface between the electrode and electrolyte and therefore inferior cyclic stability. Herein, we have proposed a straightforward method to deliver 1, 2, and 4 wt % of TiO2 nanoparticles (NPs) on the surface of the NCM811 cathode material and to improve its properties at room and high temperatures. Based on scanning electron microscopy and transmission electron microscopy observations, the coating thickness varies from 10 to 35 nm and the 2 wt %... 

    Full-core reactor physics analysis for accident tolerant cladding in a VVER-1000 reactor

    , Article Annals of Nuclear Energy ; Volume 155 , 2021 ; 03064549 (ISSN) Safarzadeh, O ; Qarani tamai, M ; Sharif University of Technology
    Elsevier Ltd  2021
    Advanced accident tolerant cladding materials have brought up the potential to delay the deleterious consequences of loos of coolant accidents related to slowing down hydrogen formation from reaction of zirconium with steam in order to minimize the additional heat generation and improve fuel and cladding retention of fission products. The performance improvement offered by these advanced materials may expand the operating envelope of existing light water reactors. This paper examines the neutronic performance of the VVER-1000 light water reactor for the application of accident tolerant cladding in order to realize the endurance of severe accident conditions. This study includes a detailed... 

    The effect of thickness and film homogeneity on the optical and microstructures of the ZrO2 thin films prepared by electron beam evaporation method

    , Article Optical and Quantum Electronics ; Volume 53, Issue 8 , 2021 ; 03068919 (ISSN) Shakoury, R ; Talebani, N ; Zelati, A ; Ţălu, Ş ; Arman, A ; Mirzaei, S ; Jafari, A ; Sharif University of Technology
    Springer  2021
    In this study, ZrO2 coatings with different thicknesses were grown by the electron beam evaporation technique. The crystalline structure was studied by XRD analysis which suggested the tetragonal and monoclinic phases for ZrO2 coatings. Additionally, the film thickness slightly enhanced the crystallinity. The surface morphology and fractal features were analyzed using Scanning Electron Microscopy (SEM). The surface statistical parameters and the fractal geometry were employed to analyze the impact of the coating thickness and homogeneity on the morphology of the films. The statistical processing and fractal dimension revealed variations in the morphology parameters due to the electron beam... 

    The effect of pore morphology and agarose coating on mechanical properties of tricalcium phosphate scaffolds

    , Article International Journal of Applied Ceramic Technology ; Volume 19, Issue 5 , 2022 , Pages 2713-2722 ; 1546542X (ISSN) Gorgin Karaji, Z ; Bagheri, R ; Amirkhani, S ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Three-dimensional biocompatible porous structures can be fabricated using different methods. However, the biological and mechanical behaviors of scaffolds are the center of focus in bone tissue engineering. In this study, tricalcium phosphate scaffolds with similar porosity contents but different pore morphologies were fabricated using two different techniques, namely, the replica method and the pore-forming agent method. The samples fabricated using the pore-forming agent showed more than two times higher compressive and bending strengths and more than three times higher compressive moduli. Furthermore, a thin layer of agarose coating improved the compressive and bending strength of both... 

    A micro mechanical study on tensile behavior of steel sheets with spheroidal cementite using crystal plasticity finite element method

    , Article Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications ; Volume 236, Issue 12 , 2022 , Pages 2357-2371 ; 14644207 (ISSN) Einolghozati, M ; Assempour, A ; Sharif University of Technology
    SAGE Publications Ltd  2022
    In this research, we investigate the effects of various microstructural features on the behavior of spherical steel sheets, using the crystal plasticity finite element method. The cementite phase ratio, the grain sizes of ferrite and cementite, and the percentage of residual pearlite in the steel structure due to incomplete annealing are the major microstructural parameters studied in this work. A grain generator software has been developed to generate hexagonal ferrite grains as well as circular cementite particles distributed in the ferrite matrix. We use a hard coating with special properties as an intermediate layer around the cementite grains to simulate the contact between ferrite... 

    Selective fabrication of robust and multifunctional super nonwetting surfaces by diverse modifications of zirconia-ceria nanocomposites

    , Article Langmuir ; Volume 38, Issue 30 , 2022 , Pages 9195-9209 ; 07437463 (ISSN) Esmaeilzadeh, P ; Zandi, A ; Ghazanfari, M. H ; Khezrnejad, A ; Fatemi, M ; Molaei Dehkordi, A ; Sharif University of Technology
    American Chemical Society  2022
    The creation of surfaces with various super nonwetting properties is an ongoing challenge. We report diverse modifications of novel synthesized zirconia-ceria nanocomposites by different low surface energy agents to fabricate nanofluids capable of regulating surface wettability of mineral substrates to achieve selective superhydrophobic, superoleophobic-superhydrophilic, and superamphiphobic conditions. Surfaces treated with these nanofluids offer self-cleaning properties and effortless rolling-off behavior with sliding angles ≤7° for several liquids with surface tensions between 26 and 72.1 mN/m. The superamphiphobic nanofluid coating imparts nonstick properties to a solid surface whereby... 

    PO43--Loaded zif-8-type metal-organic framework-decorated multiwalled carbon nanotube synthesis and application in silane coatings for achieving a smart corrosion protection performance

    , Article Industrial and Engineering Chemistry Research ; Volume 61, Issue 32 , 2022 , Pages 11747-11765 ; 08885885 (ISSN) Mohammadkhani, R ; Ramezanzadeh, M ; Fedel, M ; Ramezanzadeh, B ; Mahdavian, M ; Sharif University of Technology
    American Chemical Society  2022
    In this research study, interfacial assembled nanoporous zeolitic imidazolate framework (ZIF-8) multiwalled oxidized carbon nanotubes (MW-OCNTs) were developed and introduced into a silane coating. To analyze the destructive behavior of the nanoparticles exposed to salty solutions with three distinctive pHs of 2, 7.5, and 12, various types of tests such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and inductively coupled plasma (ICP) were accomplished. The XRD test revealed that the main characteristic peaks of ZIF-8 were eliminated and/or their intensity decreased. In accordance with the obtained data from the XRD test, nanoparticles at pH = 2 had been... 

    Carboxymethyl cellulose-based functional film integrated with chitosan-based carbon quantum dots for active food packaging applications

    , Article Progress in Organic Coatings ; Volume 166 , 2022 ; 03009440 (ISSN) Riahi, Z ; Rhim, J. W ; Bagheri, R ; Pircheraghi, G ; Lotfali, E ; Sharif University of Technology
    Elsevier B.V  2022
    A chitosan-based carbon quantum dots (CQDs) with multifunctional properties were synthesized using a hydrothermal process. The CQDs were spherical with an average size of 7.8 ± 2.4 nm. The CQD showed strong antioxidant activity, potent antibacterial activity against E. coli and L. monocytogenes, and antifungal activity against A. niger and P. chrysogenum. In addition, the prepared CQD showed negligible cytotoxicity against L929 cells even at a concentration of 500 μg/mL. Carboxymethyl cellulose (CMC)-based functional films were fabricated by adding various amounts of CQD. The CQDs were evenly dispersed in the polymer matrix to form a highly transparent UV-blocking film. The addition of CQD... 

    Ag-incorporated biodegradable Mg alloys

    , Article Materialia ; Volume 23 , 2022 ; 25891529 (ISSN) Mohammadi Zerankeshi, M ; Alizadeh, R ; Sharif University of Technology
    Elsevier B.V  2022
    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... 

    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) Esmaeilzadeh, P ; Ghazanfari, M. H ; Molaei Dehkordi, A ; Sharif University of Technology
    American Chemical Society  2022
    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... 

    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) Gerashi, E ; Alizadeh, R ; Langdon, T. G ; Sharif University of Technology
    National Engg. Reaserch Center for Magnesium Alloys  2022
    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.... 

    In situ solid-phase microextraction and post on-fiber derivatization combined with gas chromatography-mass spectrometry for determination of phenol in occupational air

    , Article Analytica Chimica Acta ; Volume 742 , 2012 , Pages 17-21 ; 00032670 (ISSN) Es haghi, A ; Baghernejad, M ; Bagheri, H ; Sharif University of Technology
    Elsevier  2012
    A method based on solid-phase microextraction (SPME) followed by on-fiber derivatization and gas chromatography-mass spectrometry detection (GC-MS) for determination of phenol in air was developed. Three different types of SPME fibers, polar and non-polar poly(dimethylsiloxane) (PDMS) and polyethylene glycol (PEG) were synthesized using sol-gel technology and their feasibility to the sampling of phenol were investigated. Different derivatization reagents for post on-fiber derivatization of phenol were studied. Important parameters influencing the extraction and derivatization process such as type of fiber coating, type and volume of derivatizing reagent, derivatization time and temperature,... 

    Novel polyamide-based nanofibers prepared by electrospinning technique for headspace solid-phase microextraction of phenol and chlorophenols from environmental samples

    , Article Analytica Chimica Acta ; Volume 716 , 2012 , Pages 34-39 ; 00032670 (ISSN) Bagheri, H ; Aghakhani, A ; Baghernejad, M ; Akbarinejad, A ; Sharif University of Technology
    A novel solid phase microextraction (SPME) fiber was fabricated by electrospinning method in which a polymeric solution was converted to nanofibers using high voltages. A thin stainless steel wire was coated by the network of polymeric nanofibers. The polymeric nanofiber coating on the wire was mechanically stable due to the fine and continuous nanofibers formation around the wire with a three dimensional structure. Polyamide (nylon 6), due to its suitable characteristics was used to prepare the unbreakable SPME nanofiber. The scanning electron microscopy (SEM) images of this new coating showed a diameter range of 100-200nm for polyamide nanofibers with a homogeneous and porous surface... 

    Superparamagnetic iron oxide nanoparticles (SPIONs): Development, surface modification and applications in chemotherapy

    , Article Advanced Drug Delivery Reviews ; Volume 63, Issue 1-2 , January–February , 2011 , Pages 24-46 ; 0169409X (ISSN) Mahmoudi, M ; Sant, S ; Wang, B ; Laurent, S ; Sen, T ; Sharif University of Technology
    At present, nanoparticles are used for various biomedical applications where they facilitate laboratory diagnostics and therapeutics. More specifically for drug delivery purposes, the use of nanoparticles is attracting increasing attention due to their unique capabilities and their negligible side effects not only in cancer therapy but also in the treatment of other ailments. Among all types of nanoparticles, biocompatible superparamagnetic iron oxide nanoparticles (SPIONs) with proper surface architecture and conjugated targeting ligands/proteins have attracted a great deal of attention for drug delivery applications. This review covers recent advances in the development of SPIONs together... 

    Silica aerogel coated on metallic wire by phase separation of polystyrene for in–tube solid phase microextraction

    , Article Journal of Chromatography A ; Volume 1500 , 2017 , Pages 69-75 ; 00219673 (ISSN) Baktash, M. Y ; Bagheri, H ; Sharif University of Technology
    Elsevier B.V  2017
    In this research, an attempt was made toward synthesizing a sol–gel–based silica aerogel and its subsequent coating on a copper wire by phase separation of polystyrene. Adaption of this new approach enabled us to coat the metallic wire with powder materials. The use of this method for coating, led to the formation of a porous and thick structure of silica aerogel. The coated wire was placed in a needle and used as the sorbent for in–tube solid phase microextraction of chlorobenzenes (CBs). The superhydrophobicity of sorbent on extraction efficiency was investigated by using different ratios of tetraethylorthosilicate/methyltrimethoxysilane. The surface coated with the prepared silica aerogel... 

    Cell toxicity of superparamagnetic iron oxide nanoparticles

    , Article Journal of Colloid and Interface Science ; Volume 336, Issue 2 , 2009 , Pages 510-518 ; 00219797 (ISSN) Mahmoudi, M ; Simchi, A ; Milani, A. S ; Stroeve, P ; Sharif University of Technology
    The performance of nanoparticles for biomedical applications is often assessed by their narrow size distribution, suitable magnetic saturation and low toxicity effects. In this work, superparamagnetic iron oxide nanoparticles (SPIONs) with different size, shape and saturation magnetization levels were synthesized via a co-precipitation technique using ferrous salts with a Fe3+/Fe2+ mole ratio equal to 2. A parametric study is conducted, based on a uniform design-of-experiments methodology and a critical polymer/iron mass ratio (r-ratio) for obtaining SPION with narrow size distribution, suitable magnetic saturation, and optimum biocompatibility is identified. Polyvinyl alcohol (PVA) has been...