High quality triethanolamine-coated Fe 3 O 4 nanocrystals can be prepared by a novel complex-coprecipitation route based on the use of triethanolamine as ligands to the iron precursors. These nanocrystals show high saturation magnetizations and excellent Cr(VI) removal performances.In the past decade, magnetite (Fe 3 O 4 ) nanocrystals (NCs) have attracted much attention due to their unique chemical and physical properties. These inherent properties make their current and promising applications in magnetic ferrofluids, magnetic response imaging and sensing, biomedical drug delivery, catalysis and other applications of magnetic nanomaterials.

Self-assembled magnetite (Fe 3 O 4 ) peony structures with petal-like nanoslices have been successfully synthesized by a low-temperature and environmentally friendly one-step aqueous method without any surfactant and calcination treatment. Powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Mo ¨ssbauer spectroscopy and superconducting quantum interference device magnetometer measurements were used to characterize the samples. The experimental results indicate that the use of the organic additive triethanolamine (N(CH 2 CH 2 OH) 3 ) has an obvious impact on the morphologies of the products. The possible formation mechanism for the Fe 3 O 4 peony structures with well-defined morphology has been presented in detail. The magnetic and electrical properties of the Fe 3 O 4 peony structures are investigated. The sample shows a ferrimagnetic behaviour with a high saturation magnetization of 88.4 emu g 21 at 295 K. Low-field magnetoresistance of ca. 22.0% is achieved in an applied magnetic field of ¡1.0 T at 295 K. In addition, the as-prepared Fe 3 O 4 peony materials are studied as adsorbents in waste-water treatment, and exhibit an excellent ability to remove Cr(VI) pollutant from aqueous solution. The Fe 3 O 4 peony sample demonstrates ca. 5.24 mg g 21 of adsorption capacity towards Cr(VI) ions favourably comparing with commercial and reported adsorbents.

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Research Institute. Hsinchu, Chutung, TAIWAN, R.0.C Many papers have already reported the excellent m n e t i c properties of SmsFeirNx (X=2-3) powders, which are suitable for making good metal composite magnet'".Up to now, the starting S8:Felr alloys that reported are mostly produced by vacuum inductioon melting (VU) process, the ingot usually consists of many free iron inside due to insufficient cooling rate during chi 11 ing process. Subsequent long homogenization treatment ( 24 hrs-1 week 1 before nitrogenization is necessary to dissolve the free iron, it seem to be uneconomic for comnercial production. In this study, we tried to prepare the SmnFel7 powders by Reduction diffusion (RD ) method followed by rapid quench to eliminate the free iron. with the benifit of omiting homogenization treatment. The proper way of nitrogenation of these RD SmaFelr powders has been studied to conpare with the effect of that in VM ShFet7 powders. 99 X pure Sm.0.. Fe and Ca povders were used for RD process to meet the