Currently, superparamagnetic functionalized systems of magnetite (Fe₃O₄) nanoparticles (NPs) are promising options for applications in hyperthermia therapy, drug delivery and diagnosis. Fe₃O₄ NPs below 20 nm have stable single domains (SSD), which can be oriented by magnetic field application. Dispersion of Fe₃O₄ NPs in silicon dioxide (SiO₂) matrix allows local SSD response with uniaxial anisotropy and orientation to easy axis, 90° or 180° . A successful, easy methodology to produce Fe₃O₄ NPs (6–17 nm) has been used with the Stöber modification. NPs were embedded in amorphous and biocompatible SiO₂ matrix by mechanical stirring in citrate and tetraethyl orthosilicate (TEOS). Fe₃O₄ NPs dispersion was sampled in the range of 2–12 h to observe the SiO₂ matrix formation as time function. TEM characterization identified optimal conditions at 4 h stirring for separation of SSD Fe₃O₄ in SiO₂ matrix. Low magnetization (M_s) of 0.001 emu and a coercivity (H_c) of 24.75 Oe indicate that the embedded SSD Fe₃O₄ in amorphous SiO₂ reduces the M_s by a diamagnetic barrier. Magnetic force microscopy (MFM) showed SSD Fe₃O₄ of 1.2 nm on average embedded in SiO₂ matrix with uniaxial anisotropy response according to Fe³⁺ and Fe²⁺ electron spin coupling and rotation by intrinsic Neél contribution.

Raman scattering spectroscopy, scanning electron microscopy, and scanning acoustic microscopy were studied on porous $\mathrm{SiC}$ layers prepared by different technological routes and subjected to reactive ion treatment. The Raman spectra revealed a number of features specific for nanocrystallite materials, which can be used for characterization and diagnostics of porous $\mathrm{SiC}$ layers for technological applications.