• Title/Summary/Keyword: $Fe_2O_3$ nanoparticles

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Fe3O4 magnetic nanoparticles provide a novel alternative strategy for Staphylococcus aureus bone infection

  • Youliang, Ren;Jin, Yang;Jinghui, Zhang;Xiao, Yang;Lei, Shi;Dajing, Guo;Yuanyi, Zheng;Haitao, Ran;Zhongliang, Deng;Lei, Chu
    • Advances in nano research
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    • v.13 no.6
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    • pp.575-585
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    • 2022
  • Due to its biofilm formation and colonization of the osteocyte-lacuno canalicular network (OLCN), Staphylococcus aureus (S.aureus) implant-associated bone infection (SIABI) is difficult to cure thoroughly, and may occur recurrently subsequently after a long period dormant. It is essential to explore an alternative therapeutic strategy that can eradicate the pathogens in the infected foci. To address this, the polymethylmethacrylate (PMMA) bone cement and Fe3O4 nanoparticles compound cylinder were developed as implants based on their size and mechanical properties for the alternative magnetic field (AMF) induced thermal ablation, The PMMA mixed with optimized 2% Fe3O4 nanoparticles showed an excellent antibacterial efficacy in vitro. It was evaluated by the CFU, CT scan and histopathological staining on a rabbit 1-stage transtibial screw model. The results showed that on week 7, the CFU of infected soft tissue and implants, and the white blood cells (WBCs) of the PMMA+2% Fe3O4+AMF group decreased significantly from their controls (p<0.05). PMMA+2% Fe3O4+AMF group did not observe bone resorption, periosteal reaction, and infectious reactive bone formation by CT images. Further histopathological H&E and Gram Staining confirmed there was no obvious inflammatory cell infiltration, neither pathogens residue nor noticeably burn damage around the infected screw channel in the PMMA+2% Fe3O4+AMF group. Further investigation of nanoparticle distributions in bone marrow medullary and vital organs of heart, liver, spleen, lung, and kidney. There were no significantly extra Fe3O4 nanoparticles were observed in the medullary cavity and all vital organs either. In the current study, PMMA+2% Fe3O4+AMF shows promising therapeutic potential for SIABI by providing excellent mechanical support, and promising efficacy of eradicating the residual pathogenic bacteria in bone infected lesions.

Synthesis of CoFe2O4 Nanoparticles as Electrocatalyst for Oxygen Evolution Reaction (산소 발생 반응 용 전기화학촉매로 사용되는 CoFe2O4 나노 입자 합성 및 특성 분석)

  • Lee, Jooyoung;Kim, Geulhan;Yang, Juchan;Park, Yoo Sei;Jang, Myeong Je;Choi, Sung Mook
    • Journal of the Korean Electrochemical Society
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    • v.23 no.4
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    • pp.97-104
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    • 2020
  • One of the main challenges of electrochemical water splitting technology is to develop a high performance, low cost oxygen-evolving electrode capable of substituting a noble metal catalyst, Ir or Ru based catalyst. In this work, CoFe2O4 nanoparticles with sub-44 nmsize of a inverse spinel structure for oxygen evolution reaction (OER) were synthesized by the injection of KNO3 and NaOH solution to a preheated CoSO4 and Fe(NO3)3 solution. The synthesis time of CoFe2O4 nanoparticles was controlled to control particle and crystallite size. When the synthesis time was 6 h, CoFe2O4 nanoparticles had high conductivity and electrochemical surface area. The overpotential at current denstiy of 10 mA/㎠ and Tafel slope of CoFe2O4 (6h) were 395 mV and 52 mV/dec, respectively. In addition, the catalyst showed excellent durability for 18 hours at 10 mA/㎠.

Superparamagnetic Properties of Nanoparticles Ni0.9Zn0.1Fe2O4 for Biomedical Applications

  • Lee, Seung-Wha;Kim, Chul-Sung
    • Journal of Magnetics
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    • v.10 no.1
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    • pp.5-9
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    • 2005
  • Nanoparticles $Ni_{0.9}Zn_{0.1}Fe_2O_4$ is fabricated by a sol-gel method. The magnetic and structural properties of powders were investigated with XRD, SEM, Mossbauer spectroscopy, and VSM. $Ni_{0.9}Zn_{0.1}Fe_2O_4$ powders annealed at $300{^{\circ}C}$ have a spinel structure and behaved superparamagnetically. The estimated size of $Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticle is about 10 nm. The hyperfine fields at 13 K for the A and B patterns are found to be 533 and 507 kOe, respectively. The ZFC curves are rounded at the blocking temperature ($T_B$)and show a paramagnetic-like behavior above $T_B$. $T_B$ of $Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticle is about 250 K. Nanoparticles $Ni_{0.9}Zn_{0.1}Fe_2O_4$ annealed at 400 and $500{^{\circ}C}$ have a typical spinel structure and is ferrimagnetic in nature. The isomer shifts indicate that the iron ions were ferric at the tetrahedral (A) and the octahedral (B). The saturation magnetization of nanoparticles $Ni_{0.9}Zn_{0.1}Fe_2O_4$ annealed at 400 and $500{^{\circ}C}$ are 40 and 43 emu/g, respectively. The magnetic anisotropy constant of $Ni_{0.9}Zn_{0.1}Fe_2O_4$ annealed at $300{^{\circ}C}$ were calculated to be 1.6 ${\times}$ $10^6$ ergs/$cm^3$.

Gas Sensing Properties of Pt Doped Fe2O3 Nanoparticles Fabricated by Sol-Gel Method (Sol-Gel 방법을 이용하여 제작된 Pt이 첨가된 Fe2O3 나노 입자의 가스 감지 특성)

  • Jang, Min-Hyung;Lim, Yooseong;Choi, Seung-Il;Park, Ji-In;Hwang, Namgyung;Yi, Moonsuk
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.30 no.5
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    • pp.288-293
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    • 2017
  • $Fe_2O_3$ is one of the most important metal oxides for gas sensing applications because of its low cost and high stability. It is well-known that the shape, size, and phase of $Fe_2O_3$ have a significant influence on its sensing properties. Many reports are available in the literature on the use of $Fe_2O_3$-based sensors for detecting gases, such as $NO_2$, $NH_3$, $H_2S$, $H_2$, and CO. In this paper, we investigated the gas-sensing performance of a Pt-doped ${\varepsilon}$-phase $Fe_2O_3$ gas sensor. Pt-doped $Fe_2O_3$ nanoparticles were synthesized by a Sol-Gel method. Platinum, known as a catalytic material, was used for improving gas-sensing performance in this research. The gas-response measurement at $300^{\circ}C$ showed that $Fe_2O_3$ gas sensors doped with 3%Pt are selective for $NO_2$ gas and exhibita maximum response of 21.23%. The gas-sensing properties proved that $Fe_2O_3$ could be used as a gas sensor for nitrogen dioxide.

A survey on the application of oxide nanoparticles for improving concrete processing

  • Khayati, Gholam Reza;Ghasabe, Hojat Mirzaei;Karfarma, Masoud
    • Advances in concrete construction
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    • v.3 no.2
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    • pp.145-159
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    • 2015
  • The evolution of nanotechnology provides materials with advance properties. It's a fast growing area of research to introduce the oxide nanoparticles into the cement pastes to improve their performance. The purpose of this paper is to review the effects of oxide nanoparticles (such as $SiO_2$, $TiO_2$, $Fe_2O_3$, $ZnO_2$, $Cr_2O_3$ and $Al_2O_3$) on both of hardened concrete properties (i.e., compressive strength, split tensile strength and flexural strength, water permeability, Abrasion resistance and pore structure of concrete) and fresh concrete properties (i.e., workability and setting time). Graphical representations of all these parameters were presented to facilitate the comparison of the effect of oxide nanoparticles on concrete processing. The paper also introduces some discussion about future work in this direction by identifying some open research area.

Toxicity Assessment of Nanopariticles Based on Seed Germination and Germination Index (씨앗발아 및 발아지수에 근거한 나노입자 독성평가)

  • Gu, Bonwoo;Kong, In Chul
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.6
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    • pp.396-401
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    • 2014
  • Nanomaterials have been widely used in many fields. This study investigates the effects of metal oxide nanoparticles (CuO, NiO, $TiO_2$, $Fe_2O_3$, $Co_3O_4$, ZnO) on germination and germination index (G.I.) of seeds, Lactuca and Raphanus. Under aqueous exposure, CuO on Lactuca shows the most significant impacts on activities compared to others, showing $EC_{50s}$ for germination and G.I. as 0.46 mg/L and 0.37%, respectively. The effects of nanoparticle phytotoxicity on seed Lactuca was much higher than that of Raphanus. In general, the toxicities on seed germination and germination index were as following orders : CuO > ZnO > NiO ${\gg}$ $TiO_2$, $Fe_2O_3$, $Co_3O_4$. No measurable inhibition was observed at 1,000 mg/L (maximum exposure concentration) of $TiO_2$, $Fe_2O_3$, $Co_3O_4$.

Post Annealing Effects on Iron Oxide Nanoparticles Synthesized by Novel Hydrothermal Process

  • Kim, Ki-Chul;Kim, Young-Sung
    • Journal of Magnetics
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    • v.15 no.4
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    • pp.179-184
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    • 2010
  • We have investigated the effects of post annealing on iron oxide nanoparticles synthesized by the novel hydrothermal synthesis method with the $FeSO_4{\cdot}7H_2O$. To investigate the post annealing effect, the as-synthesized iron oxide nanoparticles were annealed at different temperatures in a vacuum chamber. The morphological, structural and magnetic properties of the iron oxide nanoparticles were investigated with high resolution X-ray powder diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Mossbauer spectroscopy, and vibrating sample magnetometer analysis. According to the XRD and HRTEM analysis results, as-synthesized iron oxide nanoparticles were only magnetite ($Fe_3O_4$) phase with face-centered cubic structure but post annealed iron oxide nanoparticles at $700^{\circ}C$ were mainly magnetite phase with trivial maghemite ($\gamma-Fe_2O_3$) phase which was induced in the post annealing treatment. The crystallinity of the iron oxide nanoparticles is enhanced by the post annealing treatment. The particle size of the as-synthesized iron oxide nanoparticles was about 5 nm and the particle shape was almost spherical. But the particle size of the post annealed iron oxide nanoparticles at $700^{\circ}C$ was around 25 nm and the particle shape was spherical and irregular. The as-synthesized iron oxide nanoparticles showed superparamagnetic behavior, but post annealed iron oxide nanoparticles at $700^{\circ}C$ did not show superparamagnetic behavior due to the increase of particle size by post annealing treatment. The saturation of magnetization of the as-synthesized nanoparticles, post annealed nanoparticles at $500^{\circ}C$, and post annealed nanoparticles at $700^{\circ}C$ was found to be 3.7 emu/g, 6.1 emu/g, and 7.5 emu/g, respectively. The much smaller saturation magnetization value than one of bulk magnetite can be attributed to spin disorder and/or spin canting, spin pinning at the nanoparticle surface.

Facile Synthesis of Flower-like Superparamagnetic Fe3O4/BiOCl Nanocomposites as High Effective Magnetic Recyclable Photocatalyst under Visible Light

  • Wang, Wei;He, Mingyi;Zhang, Huan;Dai, Yatang
    • Journal of Magnetics
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    • v.21 no.2
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    • pp.179-182
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    • 2016
  • In this paper, 10 nm $Fe_3O_4$ nanoparticles were modified on the surface of $2{\mu}m$ flower-like bismuth oxychloride (BiOCl) spheres by a facile co-precipitation method. The results showed that the $Fe_3O_4/BiOCl$ nanocomposites exhibited excellent photocatalytic activity and superparamagnetic property ($M_s=3.22emu/g$) under visible light for Rhodamine B (RhB) degradation. Moreover, the $Fe_3O_4-BiOCl$ photocatalyst possessed magnetic recyclable property, which could maintain high photocatalytic effective even after 20 cycle times. These characteristic indicates a promising application for wastewater treatment.

Nonvolatile Memory and Photovoltaic Devices Using Nanoparticles

  • Kim, Eun Kyu;Lee, Dong Uk
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.79-79
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    • 2013
  • Quantum-structures with nanoparticles have been attractive for various electronic and photonic devices [1,2]. In recent, nonvolatile memories such as nano-floating gate memory (NFGM) and resistance random access memory (ReRAM) have been studied using silicides, metals, and metal oxides nanoparticles [3,4]. In this study, we fabricated nonvolatile memories with silicides (WSi2, Ti2Si, V2Si) and metal-oxide (Cu2O, Fe2O3, ZnO, SnO2, In2O3 and etc.) nanoparticles embedded in polyimide matrix, and photovoltaic device also with SiC nanoparticles. The capacitance-voltageand current-voltage data showed a threshold voltage shift as a function of write/erase voltage, which implies the carrier charging and discharging into the metal-oxide nanoparticles. We have investigated also the electrical properties of ReRAM consisted with the nanoparticles embedded in ZnO, SiO2, polyimide layer on the monolayered graphene. We will discuss what the current bistability of the nanoparticle ReRAM with monolayered graphene, which occurred as a result of fully functional operation of the nonvolatile memory device. A photovoltaic device structure with nanoparticles was fabricated and its optical properties were also studied by photoluminescence and UV-Vis absorption measurements. We will discuss a feasibility of nanoparticles to application of nonvolatile memories and photovoltaic devices.

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Immobilization of the Thenoyltrifluoroacetone on Sodium Dodecyl Sulfate Modified Magnetite Nanoparticles for Magnetic Solid Phase Extraction of Pb (II) from Water Samples

  • Sadeghi, Meysam;Yekta, Sina;Babanezhad, Esmaeil
    • Korean Chemical Engineering Research
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    • v.54 no.5
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    • pp.636-647
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    • 2016
  • Magnetite nanoparticles ($Fe_3O_4$ NPs) were synthesized by co-precipitating method under optimized condition. The $Fe_3O_4$ NPs coated with sodium dodecyl sulfate-thenoyltrifluoroacetone ($Fe_3O_4$ NPs-SDS-TTFA) were then exerted as the magnetic solid phase extraction (MSPE) adsorbent for the extraction process prior to introducing to a flame atomic adsorption spectrometry (FAAS). The synthesized $Fe_3O_4$ NPs-SDS-TTFA were applied for the extraction of Pb(II) ions from different water samples. The characterization studies of nanoparticles were performed via scanning electron microscopy-energy dispersive micro-analysis (SEM-EDAX), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) techniques. The substantial parameters affecting the extraction efficiency were surveyed and optimized. A dynamic linear range (DLR) of $10-400{\mu}g\;L^{-1}$ was obtained and the limit of detection (LOD, n=7) and relative standard deviation (RSD%, n= 6, $C=20{\mu}g\;L^{-1}$) were found to be $2.3{\mu}g\;L^{-1}$ and 1.9%, respectively. According to the results, the proposed method successfully applied for the extraction of Pb(II) ions from different environmental water samples and satisfactory results achieved.