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A facile approach for the preparation of core-shell structured poly(acrylic acid) (PAA)-coated Fe3O4 cluster@SiO2 nanocomposite particles as the support materials for the lipase immobilization is reported. Low- or high-molecular-weight (1800 and 100 000, respectively) PAA molecules were covalently attached onto the surface of amine-functionalized magnetic silica nanoacomposite particles. The successful preparation of particles were verified by scanning transmission electron microscopy (STEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), zeta potential measurement, and Fourier-transform infrared (FTIR) techniques. Once lipase is covalently... 

This work presents solid-state thermal decomposition synthesis of transition metal ferrites (MFe2O4, M = Zn, Ni, Cd). In this method, binary complexes of [Zn(en)3]3[Fe(ox)3]2, [Cd(en)3]3[Fe(ox)3]2 and [Ni(en)3]3[Fe(ox)3]2 (where en = ethylenediamine and ox = oxalate) are introduced as new single-source precursors to fabricate ZnFe2O4, CdFe2O4 and NiFe2O4 micro/nanostructures, respectively. X-ray powder diffraction (XRD) patterns show that pure CdFe2O4 and NiFe2O4 are formed by thermal decomposition of the single-source precursors at 800°C. When thermal decomposition of [Zn(en)3]3[Fe(ox)3]2 complex is carried out at 700 and 800°C, the final products are composed of ZnFe2O4 and metal oxides.... 

Ternary mesoporous nanocomposites of RGO/Fe3O4-ZnO were prepared successfully via hydrothermal technique. Fe3O4-ZnO core/shell nanoparticles were decorated on the surface of reduced graphene oxide platelet to improve charge separation efficiency and magnetic properties. The phase, microstructure and specific surface area of the prepared samples were determined via X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy/selected area electron diffraction (TEM/SAED) and Brunauer–Emmett–Teller (BET) techniques. A vibrating sample magnetometer (VSM) was used for recording the magnetization hysteresis curves. The methylene blue (MB)... 

Thin films of Fe73.1Cu1Nb3.1Si14.7B8.2 alloy with 200, 500, and 800 nm thicknesses have been deposited by RF sputtering. Their magnetic properties have been characterized using Alternating Gradient Field Magnetometer (AGFM) and Vibrating Sample Magnetometer (VSM). The effects of residual stresses investigated by nanoindentation experiments were conducted on the as-deposited samples. It is observed that the coercivity of as-deposited films is inversely proportional to the thickness in relation with the residual stress induced during sputtering. © 2017 Sharif University of Technology. All rights reserved  

For the efficient removal of some anionic dyes, a novel adsorbent was developed. The adsorbent was prepared by coating a synthetic polymer on magnetite nanosphere surface as a magnetic carrier. The synthesized nano-adsorbent was fully characterized using Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer, X-ray diffractometer, scanning electron microscope, and transmission electronic microscopy measurements. The synthesized nano-adsorbent showed high adsorption capacity towards removal of some anionic dyes (221.4, 201.6, and 135.3 mg g-1 for reactive red 195, reactive yellow 145, and reactive blue 19 dye, respectively) from aqueous samples. The dye adsorption was... 

In this manuscript, synthesis of cobalt/poly vinyl alcohol (PVA)/gamma alumina nanocomposite via a simple room temperature, as well as its catalyst performance were explored. Brunauer–Emmett–Teller analysis, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy were conducted. The surface area of the polymeric composite was obtained to be 280 m2/g. The cobalt loading on the nanocomposite was measured using inductivity couple plasma. Transmission electron microscopy analysis showed that the size of cobalt crystalline encapsulate inside the polymer was confined to 5 nm. Magnetic property analysis, using vibrating sample magnetometer, confirmed... 

This article reports the synthesis of a magnetic heterogeneous catalyst through the decoration of gold ions onto the cross-linked polymeric nanocomposite from 2,6-diaminopyridine. The activity of the resulting catalyst was then evaluated in the bromination of aromatic compounds. The nitrogen rich support showed a high affinity to gold ions, and the measured content of Au was 0.76 mmol g-1. The structure of the catalyst was fully characterized by using Fourier-transform infrared spectroscopy, thermogravimetric analysis, atomic absorption spectroscopy, transmission electron microscopy, scanning electron microscope, energy-dispersive X-ray spectroscopy, Brunauer-Emmett-Teller surface area... 

Hyperthermia generally means as increasing the temperature of particular region of body to rise 5 °C above the body's physiological temperature. Here, we investigate the thermal therapy of PEGylated cobalt ferrite nanoparticles prepared by hydrothermal approach on cancerous cell line in the alternative current magnetic field. To characterize of the magnetic nanoparticles (MNPs), scanning electron microscopy, dynamic light scattering, X-ray diffraction, Fourier transform infrared spectroscopy, and vibrating sample magnetometer were used. X-ray diffraction analysis confirmed the spinel phase formation of the MNPs. Cytotoxicity of MNPs using MTT assay on L929 cell lines showed the PEGylated... 

We synthesized by electrostatic self-assembly route in basic solution Fe3O4–cysteine/RGO and Fe3O4/RGO–cysteine nanocomposites. In this method, electrostatic interaction was created via negatively charged surface of the reduced graphene oxide and reduced graphene oxide–cysteine sheets and positively charged surface of the Fe3O4 and Fe3O4–Cys nanoparticles in aqueous solution. The structural and magnetic properties of the prepared samples were analyzed by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM), respectively. The dependences of magnetization as a function of... 

Microbial contamination poses a serious threat to human health. The evaluation of alternative systems and their reliability for the treatment of water is essential. In this work, a new method for the deposit of more silver nanoparticles (AgNPs) on the external surface of Fe3O4 nanoparticles is presented. Fe3O4 nanoparticles were synthesised by chemical co-precipitation and were modified in two stages using 3-mercaptopropyl trimethoxysilane and grafting allyl glycidyl ether and N, N-dimethylacrylamide. Then, AgNPs were loaded onto the modified Fe3O4 to be used for water disinfection. The resulting nanoparticles were characterised by transmission electron microscopy, X-ray powder diffraction,... 

Most recent findings on structural and magnetic properties of Fe-Ni-Co nano-powders produced by mechanical alloying and subsequent low-temperature hydrogen reduction are presented in this paper. At 300 rpm, with ball to powder weight ratio of 20, single phase nickel-cobalt ferrite is mechanically synthesized for 50 h. The as-milled powder is then subjected to 1 h hydrogen reduction at 700 °C. Hydrogen reduction results in the formation of Fe-16.5%Ni-16.5%Co nano-powders. The phases of the powders are identified by X-ray diffraction (XRD) utilizing Cu Kα radiation. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are used to study the morphology and the average... 

The structural, electrical, magnetic and high frequency properties of Ni-substituted Zn2W-type hexagonal ferrites were investigated for microwave applications. Ferrite powders with chemical compositions Ba0 · 5Sr0.5NixZn2-xFe16O27 (where Ni-substitution was varied from 0.0 to 1.5 with a step size of 0.5) were prepared using sol-gel auto-combustion at 1300 °C. X-ray diffraction (XRD) analysis confirmed the single-phase hexagonal ferrite structure. The lengths of both the axis i.e. minor and major (a, c) obtained from hkl values of XRD peaks were decreased with Ni-substitution due to the difference in ionic radius of the substituted metal ions. DC electrical resistivity obtained by two-point... 

Co-Ce doped Ni nanocrystalline ferrites having composition Ni0.8Ce0.2CoxFe2-xO4 with x = 0.00, 0.25, 0.50, 0.75, 1.00 were fabricated by sol gel auto combustion method. Synthesized samples were investigated by thermal gravimetric and differential thermal analysis (TGA-DTA), Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analysis (EDX) and vibrating sample magnetometer (VSM) to study the phase, vibrational modes, structure, surface analysis and magnetic properties respectively. Structural parameters (lattice parameters, cell volume, crystallite size and micro strains) were also calculated from XRD recorded data.... 

Pr doped spinel nanoferrites having following composition Cu Pr x Fe 2-x O 4 (x = 0, 0.25, 0.50, 0.75, 1.00) were synthesized using sol-gel route. Prosademium (Pr) which is a rare earth metal was doped to tailor the properties of the Cu spinel nanoferrites. Characterization tools such as FTIR, XRD, FESEM and VSM were employed to investigate the phase, absorption bands, structure, microstructure and magnetic properties. FTIR was used to see the absorption bands and force constants of the Pr doped Cu spinel nanoferrites. Crystallite size, lattice parameters, cell volume and micro strains were determined from XRD data. Bulk density, X-ray density and porosity of the Pr doped Cu spinel... 

We synthesized by electrostatic self-assembly route in basic solution Fe3O4–cysteine/RGO and Fe3O4/RGO–cysteine nanocomposites. In this method, electrostatic interaction was created via negatively charged surface of the reduced graphene oxide and reduced graphene oxide–cysteine sheets and positively charged surface of the Fe3O4 and Fe3O4–Cys nanoparticles in aqueous solution. The structural and magnetic properties of the prepared samples were analyzed by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM), respectively. The dependences of magnetization as a function of... 

Herein, a magnetic zirconium-based metal-organic framework nanocomposite was synthesized by a simple solvothermal method and used as an adsorbent for the removal of direct and acid dyes from aqueous solution. To enhance its adsorption performance, poly(propyleneimine) dendrimer was used to functionalize the as-synthesized magnetic porous nanocomposite. The dendrimer-functionalized magnetic nanocomposite was characterized by field-emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption isotherms, and vibration sample magnetometer. The obtained results revealed the successful synthesis and functionalization of the... 

This research reports the preparation and examination of Cadmium Telluride (CdTe) Quantum Dots and doping CdTe QDs with Europium (Eu), Gadolinium (Gd), and Manganese (Mn) prepared in aqueous solution using TGA as a capping agent. Magnetic QDs (MQDs) are important agents for fluorescence (FL) /magnetic resonance (MR) dual-modal imaging due to their excellent optical and magnetic properties. Herein, the chemical bonds, structural, fluorescence, and magnetized properties of CdTe QDs and effect of Mn, Eu, and Gd ions doping on their properties were examined by X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTM), Energy-dispersive X-ray spectroscopy (EDX),... 

Rare earths (REs) play a key role in distorting spinel structure by creating some defects at the lattice sites and make them suitable for magnetodielectric applications. In the present study, the nanoferrites of CuRE0.02Fe1.98O4, where REs = Y3+, Yb3+, Gd3+, were prepared using one step sol–gel method. The prepared samples are copper ferrite (CFO), yttrium doped copper ferrite (Y-CFO), ytterbium doped copper ferrite (Yb-CFO) and gadolinium doped copper ferrite (Gd-CFO), respectively. The single-phase structure of all the REs doped nanoferrites was determined by X-ray diffraction (XRD) analysis. The porosity, agglomerations and grain size of the REs doped copper ferrite were examined using... 

Herein, a novel Pt-APA composite (APA = pyridinium bromide salt) based on magnetic graphene oxide was synthesized and used as an effective catalyst. In this way, Fe3O4 nanoparticles are grown on graphene oxide (GO) nanosheets by a simple and practical method which creates a unique nanostructure (Fe3O4/GO) through dispersing uniformly among graphene nanosheets. The resulted Pt-APA composite was obtained via adding PtCl2 to an ethanol solution of Fe3O4/GO and α-keto stabilized pyridinium ylide in related conditions. The synthesized nanocomposite structure was identified using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive... 

NiZn nanoferrites doped with rare-earth cations having stoichiometric composition such as Ni0.5Zn0.5R0.02Fe1.98O4 (R = Tb, Pr, Ce, Gd, Y) were prepared by sol–gel technique. The same amount of Ni and Zn with constant ratio of different rare-earths ions were doped to investigate the variations in the properties. X-ray diffraction (XRD), Field emission electron microscope (FESEM), and vibrating sample magnetometer (VSM) were used to investigate the structure, morphology, and magnetic properties of rare-earth doped NiZn nanoferrites, respectively. X-ray density, bulk density, and porosity were also calculated. Phase, crystallite size, structure, d-spacing, lattice parameter, micro strain, and...