| 1. |
- Kurtan, U., et al.
(författare)
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Influence of calcination rate on morphologies and magnetic properties of MnFe2O4 nanofibers
- 2016
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Ingår i: Ceramics International. - : Elsevier. - 0272-8842 .- 1873-3956. ; 42:16, s. 18189-18195
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Tidskriftsartikel (refereegranskat)abstract
- In the present study, we succesfully synthesized electrospun MnFe2O4 nanofibers (NFs) from poly(N-vinylpyrrolidone)/manganese(II) nitrate composite by electrospinning and then as-spun NFs were calcined 450 degrees C for 2 h in air atmosphere to remove the polymer matrix and fabricate inorganic MnFe2O4 nanofibers. In order to investigate the sintering behavior of MnFe2O4 nanofibers in air atmosphere, the synthesized as-spun nanofibers were calcined with different calcination rates. Thus the effect of calcination rate on structure and morphology of nanofibers were discussed clearly. The structural, magnetic, morphological, spectroscopic and thermal characterizations were also done by XRD, VSM, TEM, SEM, FTIR and TG analysis. In the presence of slow calcination rate, only peaks of MnFe2O4 could be observed on other hand in the presence of rapid calcination rate, formation of an impurity was observed. Scanning electron microscope images revealed that MnFe2O4 nanorods possess a broader range size distribution with higher particle size. Also, magnetic properties were both size and shape dependent.
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| 2. |
- Amir, M., et al.
(författare)
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Synthesis and Characterization of CoxZn1−xAlFeO4 Nanoparticles
- 2015
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Ingår i: Journal of Inorganic and Organometallic Polymers and Materials. - : Springer Science and Business Media LLC. - 1574-1443 .- 1574-1451. ; 25:4, s. 747-754
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Tidskriftsartikel (refereegranskat)abstract
- Nanocrystalline powders of cobalt and aluminum co-substituted zinc ferrites with general formula CoxZn1−xAlFeO4 (x = 0.0–1.0) have been synthesized for the first time. Using the citrate-microwave technique and the citric acid as combustion–complexion agent (fuel), materials with spinel mono-phase cubic spinel structure were successfully prepared. The characterization of products was done by XRD, SEM and VSM. The crystallite size estimated by Scherrer formula has been found in the range of 7.7–9.6 nm. The magnetic properties were studied by room temperature (RT) VSM magnetization measurements. The small remanent magnetization (Mr) and coercivity (Hc) values reveal the superparamagnetic nature of nanoparticles (NPs) at RT. The extrapolated saturation magnetization (Ms) is maximum for Co0.8Zn0.2AlFeO4 (17.15 emu/g) and minimum for ZnAlFeO4 particles (4.22 emu/g). This case is attributed to high or low amount of cation distribution change from normal to mixed spinel structure. The average magnetic diameters (Dmag) were calculated from magnetic fit studies of M–H spectra. Dmag values are between 8.17 and 8.46 nm and this range is in great accordance with the obtained diameters from XRD measurements. The small Mr/Ms ratios (maximum, 0.219) specify the uniaxial anisotropy according to Stoner–Wohlfarth model for CoxZn1−xAlFeO4 NPs. RT effective anisotropy constants (Keff) were calculated by using Ms and Hc values. Keff constants increased with increasing Co content in the spinel NPs.
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| 3. |
- Baykal, A., et al.
(författare)
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Synthesis, Characterization, and Dielectric Properties of BaFe10(Mn2+Zn2+Zn2+)O-19 Hexaferrite
- 2016
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Ingår i: Journal of Superconductivity and Novel Magnetism. - : Springer. - 1557-1939 .- 1557-1947. ; 29:1, s. 199-205
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Tidskriftsartikel (refereegranskat)abstract
- Barium hexaferrite with nominal chemical composition BaMnZn2Fe10O19 has been synthesized by sol-gel method, using polymethyl methacrylate (PMMA) as a template. Fourier transform infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRD) were used for approving the formation of barium hexaferrites. In addition, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were performed to investigate the structural and morphological properties of BaM. The dielectric properties were studied by impedance measurements as a function of frequency (in the range 0.1 Hz-1 MHz). The XRD patterns confirmed the formation of single-phase magnetoplumbite with crystallite size around 73 nm. The results of dielectric parameters and conductivity measurements showed three regions with different behaviors in electrical conduction mechanism.
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| 4. |
- Jermy, B. Rabindran, et al.
(författare)
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Targeted therapeutic effect against the breast cancer cell line MCF-7 with a CuFe2O4/silica/cisplatin nanocomposite formulation
- 2019
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Ingår i: Beilstein Journal of Nanotechnology. - : BEILSTEIN-INSTITUT. - 2190-4286. ; 10, s. 2217-2228
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Tidskriftsartikel (refereegranskat)abstract
- The combination of magnetic nanoparticles with a porous silica is a composite that has attracted significant attention for potential multifunctional theranostic applications. In this study, 30 wt % CuFe2O4 was impregnated into a matrix of monodispersed spherical hydrophilic silica (HYPS) nanoparticles through a simple dry impregnation technique. The chemotherapy drug cisplatin was loaded through electrostatic equilibrium adsorption over 24 h in normal saline solution. The presence of cubic spinel CuFe2O4 on HYPS was confirmed through powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR) and diffuse reflectance UV-vis spectroscopy (DR UV-vis) analysis. The HYPS particles showed a surface area of 170 m(2)/g, pore size of 8.3 nm and pore volume of 0.35 cm(3)/g. The cisplatin/CuFe2O4/HYPS nanoformulation showed the accumulation of copper ferrite nanoparticles on the surface and in the pores of HYPS with a surface area of 45 m(2)/g, pore size of 16 nm and pore volume of 0.18 cm(3)/g. Transmission electron microscopy (TEM) and energy dispersive X-ray (EDX) mapping analysis showed the presence of homogeneous silica particles with nanoclusters of copper ferrite distributed on the HYPS support. Vibrating sample magnetometry (VSM) analysis of CuFe2O4/HYPS showed paramagnetic behavior with a saturated magnetization value of 7.65 emu/g. DRS UV-vis analysis revealed the functionalization of cisplatin in tetrahedral and octahedral coordination in the CuFe2O4/HYPS composite. Compared to other supports such as mesocellular foam and silicalite, the release of cisplatin using the dialysis membrane technique was found to be superior when CuFe2O4/HYPS was applied as the support. An in vitro experiment was conducted to determine the potential of CuFe2O4/HYPS as an anticancer agent against the human breast cancer cell line MCF-7. The results show that the nanoparticle formulation can effectively target cancerous cells and could be an effective tumor imaging guide and drug delivery system.
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| 5. |
- Kurtan, U., et al.
(författare)
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Magnetically Recyclable Fe3O4@His@Cu Nanocatalyst for Degradation of Azo Dyes
- 2016
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Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 16:3, s. 2548-2556
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Tidskriftsartikel (refereegranskat)abstract
- Fe3O4@His@Cu magnetic recyclable nanocatalyst (MRCs) was synthesized by reflux method using L-histidine as linker. The composition, structure and magnetic property of the product were characterized by X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), Fourier Transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry (VSM). Powder XRD, FTIR and EDAX results confirmed that the as-synthesized products has Fe3O4 with spinel structure and Cu nanoparticles with moderate crystallinity without any other impurities. The surface of the Fe3O4@His nanocomposite was covered by tiny Cu nanoparticles. We examine the catalytic activity of Fe3O4@His@Cu MRCs for the degradation of two azo dyes, methyl orange (MO) and methylene blue (MB) as well as their mixture. The reusability of the nanocatalyst was good and sustained even after 3 cycles. Therefore this innovated Fe3O4@His@Cu MRCs has a potential to be used for purification of waste water.
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