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Dysprosium-iron garnet (DyIG) nanoparticles were synthesized with the new modification of the anion resin exchange precipitation method. Nanoparticles structure and morphology were characterized by the Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The magnetic properties were studied by using a QUANTUM Design MPMS-XL system and the visible magnetic circular dichroism (MCD). The nanoparticles synthesized were of the garnet structure with an excellent crystallinity. Nanoparticles magnetic properties were close to that of the bulk DyIG crystals. Nanoparticles magnetization dependence on an external magnetic field demonstrates narrow hysteresis loop and the strong magnetization increase in high fields. Visible MCD of DyIG was studded here for the first time. The MCD spectral and temperature dependences allowed to separate contributions of the Fe and Dy sub-lattices to this effect and to analyze each sub-lattice temperature behavior.

A new patented method for the synthesis of nanosized powders of indium(III) hydroxide and oxide using the strong base anion exchange resin AV-17-8 as a precipitate agent was proposed. The effect of anions of the initial indium salt and the influence of the process duration, temperature, and counterions of resin such as hydroxide or carbonate on the yield of indium(III) hydroxide during the anion resin exchange precipitation were investigated by scanning electron microscopy, electrical conductivity measurement method, and atomic absorption analysis. Based on the obtained data, the mechanism of the anion resin exchange precipitation of indium(III) hydroxide was suggested. The products were characterized by X-ray diffraction, thermogravimetric analysis/differential scanning calorimetry, elemental analysis, Brunauer−Emmett−Teller, and transmission electron microscopy. It was found that impurity-free monophasic In 2 O 3 powders with an average particle size of 10−15 nm and specific surface area of 62−73 m 2 /g were formed after heat treatment of as-prepared products at 400 °C.