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ZnCr_1-xFe_xO₄ system (with x = 0, 0.5, 1, 1.5, and 2) at the nanoscale has been successfully synthesized by a simple combination of milling mixture of Zn, Cr, and Fe oxides precursors. X-ray diffraction and magnetic measurements were carried out on the as-milled powders. XRD pattern clearly shows that the mixed oxides are all nanosized. However, as Fe₂O₃ increases the ZnCrFeO₄ phase becomes the main phase. However, magnetic measurements do not show any significance in saturation magnetization (Ms), only when the content of Fe becomes 50% and 0.75% the Ms increased drastically to 15.4 and 16.7 emu/g respectively. However, with Fe 75% He and Mr reduced abruptly to half of their values, showing a ferromagnetic behaviour with low He.

A novel tree-like nano-cadmium sulfide (CdS) with the fractal feature is synthesized by solid-state reaction at room temperature from complex precursor with aminotrimethylenephosphonic acid (ATMP) as ligand. The obtained sample is the crystalline cubic beta cadmium sulfide. The tree is composed of nanorods with an average diameter of ca. 95 nm and a length of up to 100–650 nm. The nanorods grow in the asymmetrical "Y" shape. The amount of ATMP plays an important role in the formation of fractal structure. Nonlinear optical (NLO) measurements by the Z-scan technique exhibit that the tree-like fractal nano-CdS has the third-order nonlinear optical properties of both NLO absorption and NLO refraction with self-focusing effect and the optical limiting performance.

Nanodendritic ${\gamma }^{\prime }$-Fe₄N was successfully synthesized through a nitriding process from dendritic $\alpha$-Fe₂O₃, which was prepared by hydrothermal method using potassium ferricyanide (K₃[Fe(CN)₆]) as iron source. The structure and electromagnetic properties of this material were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and vector network analyzer (VNA). The results revealed that the dendritic morphology can be mostly inherited from $\alpha$-Fe₂O₃ to ${\gamma }^{\prime }$-Fe₄N by controlling the nitriding temperature, duration and nitrogen potential precisely. The dendritic ${\gamma }^{\prime }$-Fe₄N has the saturation magnetization of 146emu/g and the coercive force of 94Oe at 300K. The maximum reflection loss is $-12$dB at 3GHz with the thickness of 3.0mm for the composite sample.