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The magnetic nanoferrites (Fe3O4, CoFe2O4, and NiFe2O4) were synthesized via hydrothermal method using an aloe vera plant extract solution. Magnetic nanoferrites were characterized using X-ray powder diffraction (XRD), vibrating sample magnetometer (VSM), field emission electron microscope (FESEM), transmission electron microscopy (TEM), and X-ray photon spectroscopy (XPS). Cytotoxicity was obtained using the water-soluble tetrazolium salt (WST) assay. X-ray diffraction analysis also demonstrated that the size range of the nanoferrites exhibited average diameters of 6–28 nm and also exhibited high crystallinity. Results showed that all the metallic nanoparticles (NPs) are magnetic with saturation values of Fe = 52 emu/g, Co = 33 emu/g, and Ni = 20.43 emu/g. The magnetic nanoferrites exhibited a high cell viability rate at high concentrations and as shown from the optical images of the cells signifies their nontoxic and biocompatibility property. From SEM and TEM, the spherical structure was noticeable and the particle size is also in accordance with XRD. The chemical states for each NP also confirmed the successful synthesis of each nanoferrite. Not to mention, the heating capabilities of the nanoferrites were investigated and showed significant temperature increase of 6 °C–8 °C and acceptable specific absorption rate (SAR) values. Interestingly, the results assure that the materials would be suitable as magnetic mediators for magnetic hyperthermia application for cancer treatment. [ABSTRACT FROM AUTHOR]

X-ray diffraction methods and DSC thermal analysis have been used to investigate the structural change of nylon 6/clay nanocomposites. Nylon 6/clay has prepared by the intercalation of ζ-caprolactam and then exfoliaton of the layered saponite or montmorillonite by subsequent polymerization. Both X-ray diffraction data and DSC results indicate the presence of polymorphism in nylon 6 and in nylon 6/clay nanocomposites. This polymorphic behavior is dependent on the cooling rate of nylon 6/clay nanocomposites from melt and the content of saponite or montmorillonite in nylon 6/clay nanocomposites. The quenching from the melt induces the crystallization into the γ crystalline form. The addition of clay increases the crystallization rate of the α crystalline form at lower saponite content and promotes the heterophase nucleation of γ crystalline form at higher saponite or montmorillonite content. The effect of thermal treatment on the crystalline structure of nylon 6/clay nanocomposites in t he range between Tg and Tm is also discussed., INTRODUCTION Polymer nanocomposites, defined by the particle size of the dispersed phase containing at least one dimension in the range of 1~100 nm, have received increasing interest because of their [...]

The fluorescence quantum efficiency and the internal conversion quantum yield of 0.59 plusmn 0.02, and the intersystem crossing quantum yield of 0.11 plusmn 0.01 are presented. The fluorescence lifetime of ca. 490 ps is measured to estimate the relative lifetime of 1.64 ns for the singlet excitons and nonradiative decay rate constants, for the internal conversion and intersystem crossing.