Preparation of Graphene Oxide-Maghemite-Chitosan Composites for the Adsorption of Europium Ions from Aqueous Solutions.

The adsorption of Eu(III) on composites synthesised from graphene oxide (GO), maghemite (MGH), and chitosan (CS) has been studied using different approaches. The physicochemical and morphological characteristics of the composites GO-MGH, GO-CS, GO-MGH-CS I, II, and III were determined by XRD, Mössbauer spectroscopy, FTIR, Raman spectroscopy, and TEM. According to the results of batch experiments, the maximum experimental adsorption capacity was 52, 54, 25, 103, and 102 mg/g for GO-MGH, GO-CS, GO-MGH-CS I, II, and III, respectively.

Sol-Gel Synthesis and Characterization of Yttrium-Doped MgFeO Spinel.

In this study, an environmentally friendly sol-gel synthetic approach was used for the preparation of yttrium-doped MgFeO. Two series of compounds with different iron content were synthesized and A-site substitution effects were investigated. In the first series, the iron content was fixed and the charge balance was suggested to be compensated by a partial reduction of Fe to Fe or formation of interstitial O ions.

Adsorption of caesium and cobalt ions on the muscovite mica clay-graphene oxide-γ-FeO-FeO composite.

The muscovite mica clay-graphene oxide-maghemite-magnetite (γ-FeO-FeO) composite was first used for the adsorption of caesium(I) and cobalt(II). The presence of clay minerals, graphene oxide, maghemite, and magnetite was detected in the prepared composite by XRD, WD-XRF, Mössbauer spectroscopy, and ATR-FTIR. The SEM and TEM results show that the composite has a layered structure with irregularly shaped pores on the surface.

Lanthanum and Manganese Co-Doping Effects on Structural, Morphological, and Magnetic Properties of Sol-Gel Derived BiFeO.

In this work, lanthanum and manganese co-substitution effects on different properties of bismuth ferrite solid solutions BiLaFeMnO (x from 0 to 1) prepared by a sol-gel synthetic approach have been investigated. It was observed that the structural, morphological, and magnetic properties of obtained specimens are influenced by the amount of introduced La ions. Surprisingly, only the compound with a composition of BiFeMnO was not monophasic, and the presence of neighboring phases was determined from X-ray diffraction analysis and Mössbauer measurements.

Aqueous Sol-Gel Synthesis of Different Iron Ferrites: From 3D to 2D.

In this study, an aqueous sol-gel synthesis method and subsequent dip-coating technique were applied for the preparation of yttrium iron garnet (YIG), yttrium iron perovskite (YIP), and terbium iron perovskite (TIP) bulk and thin films. The monophasic highly crystalline different iron ferrite powders have been synthesized using this simple aqueous sol-gel process displaying the suitability of the method. In the next step, the same sol-gel solution was used for the fabrication of coatings on monocrystalline silicon (100) using a dip-coating procedure.

Features of iron accumulation at high concentration in pulcherrimin-producing Metschnikowia yeast biomass.

In previous studies it was found that the antimicrobial properties of pulcherrimin-producing Metschnikowia species are related to the formation of a red pigment-pulcherrimin and sequestration of free iron from their growth medium. For strains of Metschnikowia pulcherrima, M. sinensis, M.

Inactivation of Bacteria Using Bioactive Nanoparticles and Alternating Magnetic Fields.

Foodborne pathogens are frequently associated with risks and outbreaks of many diseases; therefore, food safety and processing remain a priority to control and minimize these risks. In this work, nisin-loaded magnetic nanoparticles were used and activated by alternating 10 and 125 mT (peak to peak) magnetic fields (AMFs) for biocontrol of bacteria a suitable model to study the inactivation of common foodborne pathogen It was shown that features high resistance to nisin-based bioactive nanoparticles, however, application of AMFs (15 and 30 min exposure) significantly potentiates the treatment resulting in considerable log reduction of viable cells. The morphological changes and the resulting cellular damage, which was induced by the synergistic treatment, was confirmed using scanning electron microscopy.

Study of gadolinium substitution effects in hexagonal yttrium manganite YMnO.

In the present work, gadolinium substitution effects on the properties of yttrium manganite YGdMnFeO (x from 0 to 1 with a step of 0.2) synthesized by an aqueous sol-gel method have been investigated. Partial substitution of Mn by Fe in the manganite was also performed in order to investigate deeper the structural properties of synthesized compounds applying Mössbauer spectroscopy.

A Facile Synthesis and Characterization of Highly Crystalline Submicro-Sized BiFeO.

In this study, a highly crystalline bismuth ferrite (BFO) powder was synthesized using a novel, very simple, and cost-effective synthetic approach. It was demonstrated that the optimal annealing temperature for the preparation of highly-pure BFO is 650 °C. At lower or higher temperatures, the formation of neighboring crystal phases was observed.

Fe and Zn co-substituted beta-tricalcium phosphate (β-TCP): Synthesis, structural, magnetic, mechanical and biological properties.

In the present work, Fe and Zn co-substituted β-tricalcium phosphate (β-TCP) has been synthesized by wet co-precipitation method. Co-substitution level in the range from 1 to 5 mol% has been studied. Thermal decomposition of as-prepared precipitates was shown to be affected by introducing of foreign ions, decreasing the decomposition temperature of precursor.

Behaviour of (99)Tc in aqueous solutions in the presence of iron oxides and microorganisms.

A set of experiments was performed to determine the factors that influence TcO4(-) interaction with Fe-bearing minerals and to explore the effect of microbial activity on the behaviour of Tc(VII) in solution, in the presence of iron oxides under oxidizing medium. Gradual sorption of TcO4(-) (aq) onto wustite/magnetite was observed under alkaline conditions (pH 8-9). No pronounced effect of TcO4(-) (aq) interaction with hematite was observed in the investigating alkaline systems.