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Magnetic nanoparticles for thermotherapy must be biocompatible and possess high thermal efficiency as heating elements. The biocompatibility of Mg 0.8 Ni 0.2 Fe 2 O 4 nanoparticles was studied using a cytotoxicity colony formation assay and a cell viability assay. HeLa cells exhibited cytotoxic effects when exposed to three different concentrations of 150 μg /ml, 100 μg /ml, and 50 μg /ml nanoparticles. Therefor e, c oncentrations of 50 μg /ml showed the lowest cytotoxic activity and the lowest toxicity to living cells. In vitro cytotoxicity of samples was then investigated by two methods, colony formation assay and cell viability assay. The Hela inhibited cell growth as 16.8% during heating by magnetic field generators.

Magnetic properties of fully oxygenated bare CuO nanoparticles have been investigated using magnetization, X-ray diffraction, neutron diffraction, and Raman scattering measurements. The Langevin field profile is clearly revealed in the isothermal magnetization of 8.8 nm CuO nanoparticle assembly even at 300 K, revealing a 172 times enhancement of the ferromagnetic responses over that of bulk CuO. Surface magnetization of 8.8 nm CuO reaches 18% of the core magnetization. The Cu spins in 8.8 nm CuO order below 400 K, which is 1.7 times higher than the 231 K observed in bulk CuO. A relatively simple magnetic structure that may be indexed using a modulation vector of (0.2, 0, 0.2) was found for the 8.8 nm CuO, but no magnetic incommensurability was observed in bulk CuO. The Cu spins in 8.8 nm CuO form spin density waves with length scales of 5 chemical unit cells long along the crystallographic a- and c-axis directions. Considerable amounts of electronic charge shift from around the Cu lattice sites toward the interconnecting regions of two neighboring Cu–Cu ions, resulting in a stronger ferromagnetic direct exchange interaction for the neighboring Cu spins in 8.8 nm CuO.

Neutron diffraction has been used for in-situ studying of the charge–discharge processes in commercial lithium batteries with LiFePO 4 (LFP) and graphite electrodes. The diffraction data were obtained with time-of-flight diffractometer in the process of three complete charge–discharge cycles performed at a low rate (0.1 C) at room temperature. The experimental data allowed detailed tracing of the multistage process of Li insertion into graphite followed by the formation of several LiC n phases, as well as the reversible transition of LiFePO 4 ↔ FePO 4 . A comparison of the charge–discharge processes in a battery with a pure LFP cathode and LFP containing ∼1% of vanadium (LFPV) is made. In the second case, an evidently larger part of the anode material passes into the final LiC 6 state. Analysis of the diffraction patterns of LFP and LFPV powders revealed a marked shrinkage of crystallite size in the LFPV case, which correlates with better electrochemical properties of LFPV compared to LFP.

Ex-situ and in-situ neutron diffraction experiments were performed at HRFD time-of-flight (TOF) diffractometer (IBR-2 long-pulsed reactor, JINR) to characterize the entire battery system based on LiFePO4 and V-added LiFePO4 electrodes during electrochemical cycling and to find additional information about crystal structure of electrodes. Another purpose of this work was checking possibilities for in-situ experiments with real Li-ion batteries at the IBR-2 pulsed reactor. An important advantage of TOF method is the possibility to work at the fixed geometry of the experiment, which allows selecting the optimal battery orientation relative to the directions of the incident and scattered neutron beams and, thus, to minimize the difficulties associated with complex internal structure of the battery. It was shown that charge/discharge process of Li-based real Li-ion battery can be effectively studied by TOF technique at the IBR-2 pulsed reactor. Three full charge/discharge cycles were realized at room temperature (~170C) with slow rate. The step-like appearance of several LiCn phases was observed and the volume fractions of LiFePO4 and FePO4 structural phases at different states of charge were determined. The analysis of changes in cathode material microstructure when doped with vanadium showed a significant increase in the density of defects, which correlates with better electrochemical properties of V-added LiFePO4 compared to pure LiFePO4.