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Information × Registration Number 0217U004774, 0116U001213 , R & D reports Title Stabilization of colloids of ferromagnetic nanoparticles in nematic and smectic liquid crystals popup.stage_title Head Vashchenko Valeriy Vladimirovich, Registration Date 02-03-2017 Organization State Scientific Institution "Institute for Single Crystals" of National Academy of Sciences of Ukraine popup.description2 Ferromagnetic CoFe2O4 nanoparticles (FNPs) with diameter about 7.8 nm were synthesized, which have been modified with mixture of dendritic oligomesogenic surfactant and hexylphosphonic acid (1/4), that allows to obtain stable colloids such particles in nematic liquid crystals. As a ferroelectric liquid crystal (FLC) mixture was used comprised phenylpyrimidine chiral additive and lactate at a concentration of 14%. The frequency dependence of the real and imaginary parts of the complex dielectric permittivity of the FLC host and colloids of NPs in FLC were measured. The strong shift of the maximum in the high frequency region, as well as a decrease in the amplitude of the variance were observed in the dielectric spectrum of FNPs in FLC. Both effects depend on the concentration of the FNPs. Measurements of the temperature dependence of the main macroscopic parameters showed that they almost do not change with the introduction in the FNPs in FLC. Consequently, changes in the dielectric spectrum dispersions IPM occur due to increased modulus, as evidenced by increasing voltage required for complete promotion of supramolecular helix FLC dispersion with FNPs. It is shown that these dispersions are stable over time. No significant effect of a magnetic field on the parameters FLC dispersions with FNPs detected. Product Description popup.authors Ващенко В. В. Проданов М. Ф. popup.nrat_date 2020-04-02 Close