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nanocomposites
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Synthesis of new electromagnetic nanocomposite based on modified Fe3O4 nanoparticles with enhanced magnetic, conductive, and catalytic properties
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 65, Issue 8 , 2016 , Pages 384-390 ; 00914037 (ISSN) ; Doroudian, M ; Afshar Saveh, Z ; Doulabi, M ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
A new method for the fabrication of an electromagnetic nanocomposite based on Fe3O4 and polyaniline (PANI) is offered. The authors focused on improvement of the physical and electromagnetic properties of the nanocomposite using a new synthetic method. Supermagnetic Fe3O4 nanoparticles were synthesized through coprecipitation method. As a chemical modification, the third generation of poly (amidoamine) dendrimer was grafted on the surface of the nanoparticles. PANI was grafted from -NH2 functional groups of dendrimer via in situ polymerization of aniline. Finally, Au nanoparticles were loaded on the nanocomposite and its catalytic activity for reduction reactions was studied
Investigation of the modification process and morphology of organosilane modified nanoclay
, Article Ceramics - Silikaty ; Volume 53, Issue 4 , 2009 , Pages 254-259 ; 08625468 (ISSN) ; Bazgir, S ; Tamizifar, M ; Nemati, A. L. I ; Arzani, K ; Sharif University of Technology
Abstract
This work deals with the preparation of epoxy-clay nanocomposites. The results show that the mechanical properties of nanocomposites depend on their compatibility, the epoxy resin used and the purity of the nanoclay. The used bentonite was purified and the effects of the organoclay synthesis and various additives on its characteristics were evaluated. X-ray Diffraction (XRD), X-ray Fluorescence (XRF) and Scanning Electron Microscopy (SEM) were used to analyze the microstructure and the phase composition of the nanoclay. The XRD results revealed that when the modifier addition was increased from 10wt.% to 40 wt.%, the interlayer spacing of the nanoclay increased from 12.43 Å being...
Preparation and fatigue behavior of graphene-based aerogel/epoxy nanocomposites
, Article Materialpruefung/Materials Testing ; Volume 63, Issue 2 , 2021 , Pages 163-168 ; 00255300 (ISSN) ; Nazari, S. A ; Emam, A ; Najafi, M ; Saryazdi, M. G ; Sharif University of Technology
Walter de Gruyter GmbH
2021
Abstract
In this research, the effect of adding graphene-based aerogel ((G)A) nanoparticles on the tensile and fatigue behavior of the epoxy polymer was investigated. Specimens of nanocomposites were prepared by adding 0.05, 0.1, 0.2, 0.5, 1, and 2 wt.-% (G)A nanoparticles to the epoxy polymer. Tensile tests revealed that the 0.1 wt.-% graphene-based aerogel/ epoxy ((G)A/E) nanocomposites had the highest increase in tensile strength with 19 % growth compared to neat epoxy. Also, the tensile modulus increased by 15 % in the 0.5 wt.-% (G)A/E nanocomposites. A substantial improvement in fatigue life of the epoxy polymer was observed on adding 0.1 wt.-% (G)A nanoparticles. For instance, the fatigue life...
Trends and challenges of biopolymer-based nanocomposites in food packaging
, Article Comprehensive Reviews in Food Science and Food Safety ; Volume 20, Issue 6 , 2021 , Pages 5321-5344 ; 15414337 (ISSN) ; YousefniaPasha, H ; Tabatabaeekoloor, R ; Pesaranhajiabbas, E ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
The ultimate goal of new food packaging technologies, in addition to maintaining the quality and safety of food for the consumer, is to consider environmental concerns and reduce its impacts. In this regard, one of the solutions is to use eco-friendly biopolymers instead of conventional petroleum-based polymers. However, the challenges of using biopolymers in the food packaging industry should be carefully evaluated, and techniques to eliminate or minimize their disadvantages should be investigated. Many studies have been conducted to improve the properties of biopolymer-based packaging materials to produce a favorable product for the food industry. This article reviews the structure of...
A short review on transition metal chalcogenides/carbon nanocomposites for energy storage
, Article Nano Futures ; Volume 6, Issue 3 , 2022 ; 23991984 (ISSN) ; Rastgoo Deylami, M ; Askari, M. B ; Hooshyari, K ; Sharif University of Technology
Institute of Physics
2022
Abstract
Introducing suitable electrode materials and electrolytes for supercapacitors and next-generation batteries should be considered for the industrial application of these devices. Among the proposed materials for them, transition metal chalcogenides (TMCs), are attractive and efficient options due to their unique properties such as appropriate layered structure, good oxidation state of transition metals, high thermal and mechanical stabilities, etc. However, applying other layered materials with high electrical conductivity e.g. carbon-based materials can lead to producing remarkable results for the mentioned applications. However, an interesting point is how making TMCs composite with...
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...
Production of Sn Base Composite Solder Reinforced by Nanoparticles Via Melt-spinning Technique
, M.Sc. Thesis Sharif University of Technology ; Tavakkoli, Rouhollah (Supervisor)
Abstract
Lead-containing solder alloys in particular Sn-37Pb is the most common alloy used in electronics industry, this alloy has the good mechanical properties and excellent wetting properties and low prices. Recently, increasing environmental and health concerns over the toxicity of lead combined with strict legislation to ban the use of lead-based solders have provided an inevitable driving force for the development of lead-free solder alloys. A group of these lead-free solders are nanocomposite solders that because of having the reinforcement nano particles exhibit lots of unique properties, such as good mechanical and thermal properties. The aim of this research produce a new tin base...
Preparation of Biodegradeble Nanocomposite with Appropriate Physical and Mechanical Properties for Bread Packaging
, M.Sc. Thesis Sharif University of Technology ; Ramezani Saadat, Ahmad (Supervisor) ; Mohammadi, Mohammad Reza (Supervisor)
Abstract
Platelet nanoparticles could dramatically decrease permeability of polymeric film where increase considerably its physical -mechanical properties. Bio based (Biodegradable) polymeric materials such as starch based polymeric films show very weak mechanical and high oxygen and water vapor permeability. Graphene oxide (GO) could increase mechanical properties of starch based polymer where decrease its permeability dramatically. Addition of chitosan also could increase antibacterial and antifungal of films and decrease permeability of films considerably. In this research nanocomposite of Starch/Chitosan/GO films have been prepared by solution method and its morphology, permeability, physical...
Electrodeposition of Cu/WC Nanocomposite
, M.Sc. Thesis Sharif University of Technology ; Dolati, Abolghasem (Supervisor) ; Afshar, Abdollah (Supervisor)Friction-Stir Processed Al-Al3Ti-MgO Hybrid Nanocomposites
, M.Sc. Thesis Sharif University of Technology ; Kokabi, Amir Hossein (Supervisor) ; Simchi, Abdolreza (Supervisor)
Abstract
In recent years, investigation of mechanical properties of micro- and nano-structure materials, and peculiarly nanocomposites have been attracted a wide variety of researches. In this regard, friction-stir-processed (FSPed) metal matrix nanocomposites have been considered an important case with appropriate mechanical properties especially for fabrication of ultra-fine grained Al alloys and Al-matrix nanocomposites. In this research, Al matrix hybrid nanocomposites were fabricated via multi passes-friction stir processing (FSP) of Al-Mg alloy (AA5052) with different amounts (~2 and 3 vol%) of pre-placed TiO2 (30 nm) particles nanoparticles. It was revealed that employing of cumulative FSP up...
Fabrication & Characterization of Al-Al3Ti-Al2O3 Nano-composites Based on the Thermal Degradation of Aluminium Titanate & Facile Study on the Correlation between Microstructure & Their Mechanical Properties
, M.Sc. Thesis Sharif University of Technology ; Maddah Hosseini, Hamid Reza (Supervisor)
Abstract
In this study insitu Al-Al3Ti-Al2O3 nanocomposite has been fabricated based on thermal decomposition of tialite (Al2TiO5) precursor in aluminium matrix through powder metallurgy method. Also the effect of high energy mechanical milling and hot extrusion on this procedure has been investigated. In the first step nano-structured tialite were synthesized through citrate sol gel methods. Then, different volume fraction of tialte was mixed with aluminium by high energy vibratory milling. The results of X-ray differaction analysis, scanning electron microscopy and differential thermal analysis showed that mechanical milling can degrade stability of tialite and cause strain-induced decomposition,...
Manufacturing of Polymeric Biodegradable Nanocomposites for Musculoskeletal Fixation Devices
, M.Sc. Thesis Sharif University of Technology ; Ramezani Saadatabadi, Ahmad (Supervisor) ; Emami Meibodi, Mohammad Kazem (Co-Advisor)
Abstract
Fixation devices and implants are the most applied devices in orthopedic operation and dentistry. Interference screw is one of these devices that is made by biodegradable nanocomposite polymeric materials in this project. The purpose of this project is designing interference screw, applicable to body, and doing related tests since in vivo tests. For this purpose, hand injection molding, was designed to prepare screws in laboratory scale, first. For making samples, poly(D,L) lacticacid, nano hydroxyapatite as reinforce and polyethylene glycol as plasticizer were used. These samples were made by combination of solvent casting and melt processing methods. Adding nano hydroxyapatite and...
Fabrication and Characterization of Bioactive PLGA- TiO2 Nanocomposite Scaffold by Air-liquid Foaming for Bone Tissue Engineering
, Ph.D. Dissertation Sharif University of Technology ; Madaah Hosseini, Hamid Reza (Supervisor) ; Samadi Kuchaksaraei, Ali (Co-Supervisor)
Abstract
Poly (lactate-co-glycolate) is a typical biocompatible and biodegradable synthetic polymer. Addition of TiO2 nanoparticles improved compressive modulus of PLGA scaffolds and reduced fast degradation. Porous 3D scaffolds, which are synthesized using biocompatible and biodegradable materials, could provide suitable microenvironment and mechanical support for optimal cell growth and function. A novel method has been applied to fabricate PLGA/TiO2 scaffolds without using any organic solvent or porogen for nucleation compared to former ways, with aim of improving the biocompatibility, macroscale morphology and well inter-connected pores efficacy: Air-Liquid Foaming. Adjustment of the foaming...
Cryogenic friction-stir processing of ultrafine-grained Al-Mg-TiO2 nanocomposites
, Article Materials Science and Engineering A ; Vol. 620, issue , 2014 , pp. 471-482 ; ISSN: 09215093 ; Gerlich, A. P ; Simchi, A ; Kokabi, A. H ; Sharif University of Technology
Abstract
Submerged friction-stir processing under cryogenic conditions was employed to fabricate ultrafine-grained nanocomposites with enhanced mechanical characteristics. Al-Mg alloy sheet with 3vol% TiO2 nanoparticles were processed under air (ambient temperature), a water-dry ice medium (~-25°C), and liquid nitrogen. It is shown that a homogenous distribution of reinforcement particles throughout the metal matrix is attained at a rotational speed of 1400rpm and a traverse velocity of 50mm/min after 4 passes. In situ formation of Al3Ti and MgO nanophases during multi-pass processing is shown by transmission electron microscopy. Under the cryogenic cooling condition, ultrafine grains and cellular...
Gadolinium triflate immobilized on magnetic nanocomposites as recyclable Lewis acid catalyst for acetylation of phenols
, Article Nanoscience and Nanotechnology Letters ; Vol. 6, issue. 4 , 2014 , p. 309-313 ; Kim, A ; Shokouhimehr, M ; Sharif University of Technology
Abstract
The acetylation of phenols with acetic anhydride proceeded in excellent yields when it was catalyzed by gadolinium triflate immobilized on magnetically recyclable nanocomposites. This heterogeneous catalyst provided high catalytic activity with low loading level (1 mol%), because the Lewis acid catalyst was grafted on the surface of the nanocomposites. The catalysts were also easily recovered from the reaction mixture using a magnet and reused for six consecutive cycles
Reverse martensitic transformation in alumina-15 vol% zirconia nanostructured powder synthesized by high energy ball milling
, Article Journal of Alloys and Compounds ; Volume 459, Issue 1-2 , 2008 , Pages 531-536 ; 09258388 (ISSN) ; Banerjee, M. K ; Sharif University of Technology
2008
Abstract
In the present work, three alumina-15 vol% zirconia composites with Y2O3, MgO as dopants and without oxide as dopant have been investigated. High energy ball milling (HEBM) provides the positive thermodynamic driving force for monoclinic to tetragonal transformation and it reduces starting temperature for the reverse martensitic transformation, meanwhile mobility of zirconium cations and oxygen anions are enhanced in zirconia by HEBM. The general, albeit heuristic, reasoning is corroborated by nanocrystallity, particle size and also the retained monoclinic seem to play an important role. After 10 h HEBM, approximately 28% zirconia tetragonal phase is achieved. Non-stoichiometric tetragonal...
Enhancing seebeck coefficient and electrical conductivity of polyaniline/carbon nanotube–coated thermoelectric fabric
, Article Journal of Industrial Textiles ; 2021 ; 15280837 (ISSN) ; Ramazani Saadatabadi, A ; Pourjahanbakhsh, M ; Siadati, M. H ; Sharif University of Technology
SAGE Publications Ltd
2021
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...
Magnetic carbon nanocomposite derived from waste tire rubber for atrazine removal from aqueous solutions
, Article Desalination and Water Treatment ; Volume 252 , 2022 , Pages 219-232 ; 19443994 (ISSN) ; Borghei, M ; Takdastan, A ; Javid, A. H ; Zazouli, M. A ; Sharif University of Technology
Desalination Publications
2022
Abstract
In this study magnetite nanoparticles (Fe3 O4) were synthesized and embedded in activated carbon (AC) derived from waste tire rubber to produce magnetic activated carbon. The atrazine (C8 H14 ClN5) adsorption was performed over (AC/Fe3 O4) nanocomposite in an aqueous solution and adsorp-tion isotherms and kinetics were determined. The effects of some parameters such as (pH, contact time, adsorbent dosage and initial pesticide concentration) were investigated. Characterization of nanocomposite was carried out by high-resolution scanning electron microscopy and transmission electron microscopy, X-ray powder diffraction, vibrating sample magnetometer, Brunauer–Emmett– Teller, Fourier-transform...
Synergistic Wound Healing by Novel Ag@ZIF-8 Nanostructures
, Article International Journal of Pharmaceutics ; Volume 629 , 2022 ; 03785173 (ISSN) ; Mohsen Dehnavi, S ; Ahmadi Seyedkhani, S ; Yahya Rahnamaee, S ; Golizadeh, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In this paper, novel zeolitic imidazolate framework-8 (ZIF-8) functionalized with Ag (Ag@ZIF-8) nanoparticles were synthesized through a green, facile and environmental-friendly process for wound dressing applications. X-ray diffraction revealed that the ZIF-8 and Ag@ZIF-8 were successfully synthesized by green solvents at ambient temperature. Field-emission scanning electron microscopy indicated a homogeneous porous blend of ∼30 nm chitosan/bacterial cellulose (CS/BC) nanofibers embedded with ∼80–110 nm nanoparticles of the ZIF-8 and Ag@ZIF-8. Transmission electron microscopy revealed the Ag@ZIF-8 nanostructures consist of ZIF-8 cores that are covered by 5–20 nm Ag nanoparticles. MTT assay...
Fabrication of a magnetic alginate-silk fibroin hydrogel, containing halloysite nanotubes as a novel nanocomposite for biological and hyperthermia applications
, Article Scientific Reports ; Volume 12, Issue 1 , 2022 ; 20452322 (ISSN) ; Sadat, Z ; Aghamirza Moghim Aliabadi, H ; Ganjali, F ; Kashtiaray, A ; Salimi Bani, M ; Komijani, S ; Ahadian, M. M ; salehpour, N ; Ahangari Cohan, R ; Maleki, A ; Sharif University of Technology
Nature Research
2022
Abstract
In this study, the main focus was on designing and synthesizing a novel magnetic nanobiocomposite and its application in hyperthermia cancer treatment. Regarding this aim, sodium alginate (SA) hydrogel with CaCl2 cross-linker formed and modified by silk fibroin (SF) natural polymer and halloysite nanotubes (HNTs), followed by in situ Fe3O4 magnetic nanoparticles preparation. No important differences were detected in red blood cells (RBCs) hemolysis, confirming the high blood compatibility of the treated erythrocytes with this nanobiocomposite. Moreover, the synthesized SA hydrogel/SF/HNTs/Fe3O4 nanobiocomposite does not demonstrate toxicity toward HEK293T normal cell line after 48 and 72 h....