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The article discusses the preparation of a magnetic spherical alumina support through the controlled hydrolysis of aluminum isopropoxide. Various methods used in the preparation are mentioned, including coprecipitation to synthesize magnetite Fe3O4 nanoparticles, the sodium silicate acidification method to coat the surface of Fe3O4 with silica film, and controlled hydrolysis to support alumina on the Fe3O4/SiO2 film. Microemulsion was used to create palladium catalysts supported with the magnetic alumina. Following several processes including X-ray diffraction, transmission electron microscopy, and scanning electron microscopy, results showed superparamagnetic behavior, zero coercivity, and zero remanence.

Crystalline lithium metasilicate (Li2SiO3) nanoparticles have been synthesized using a sol–gel process with tetraethylorthosilicate and lithium ethoxide as precursors. The particle size examined by using transmission electron microscopy and BET-specific surface area techniques is in the range 5–50 nm, depending on the temperature at which the material is calcined. The crystalline Li2SiO3 forms at ambient temperature (∼40°C), and it remains in this phase after calcination at temperatures up to 850°C. The BET-specific surface area is ∼110 m2/g for material calcined at temperatures below 500°C, decreasing to ∼29 and ∼0.7 m2/g following calcination at 700° and 850°C, respectively. Solid-state 29Si NMR spectroscopy shows the presence of only Q2 structural units in the material. The lithium metasilicate is further characterized using differential scanning calorimetry and thermogravimetric analysis, and Fourier transform infrared spectroscopy. [ABSTRACT FROM AUTHOR]