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A zone refining processing was utilized to purify tellurium (Te) metal using a locally melted zone caused by high-frequency induction heating. The travel rate of the molten zone was set as a parameter. The purification efficiency for each impurity (Bi, Sb, Sn, and Se) in the tellurium sample was analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES), and the experimental results were compared with the theoretical results furnished by the proposed model to validate its predictions. The experimental results indicated that a lower travel rate of the molten zone and repetition of passes were more efficient for purification. The effective distribution coefficient k eff and the k eff values of bismuth, antimony, tin, and selenium were 0.5, 0.35, 0.22, and 0.58, respectively. These elements were effective for the purification of Te by zone refining. The obtained distribution coefficient k eff values of impurities can be used as standards for the purification of Te by zone refining. The Vickers hardness was measured, and a correlation between hardness and concentration was observed, with an average Vickers hardness was 62 Hv .

High-purity Nd metal was recovered from waste Nd–Fe–B magnet by the molten salt electrowinning process with chemical pretreatment. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), cyclic voltammetry (CV), chronopotentiometry (CP), and inductively coupled plasma-atomic emission spectrometer (ICP/AES) were used to characterize the deposit and electrochemical behaviors. The results show that NdF3 is effectively synthesized from the Nd–Fe–B magnet using HCl solution and NH4F. During the chemical treatment of the waste magnet, iron impurity is eliminated as a soluble [NH4]3[FeF6] complex. Electrowinning using NdF3 in LiF molten salt shows that Nd metal is deposited from the electrolyte on the cathode at the reduction potentials ranging from −1.48 to −1.35 V (vs. W) with the concentration change of NdF3. The final purity of Nd metal deposit is higher than 99.78 %.

In this paper, we describe an attractive and rapid process for preparing zirconium metal (sponge and powder) by reacting zirconium tetrachloride with magnesium powder. The process was carried out in the combustion synthesis (shortly CS) mode using a ZrCl4–2Mg exothermic mixture, which provided a temperature of 1000–1100 °C and a final product consisting of MgCl2 and Zr sponge. The separation of Zr sponge from the reaction product was accomplished by dissolving MgCl2 into warm acidified water. The average size of the Zr sponge particles ranged from about 1 mm to about 10 mm. Micrometer-sized (from 10 to 300 μm) Zr powders were also obtained after mechanical processing of sponge. The characteristics of the Zr metal were established by X-ray diffraction, scanning electron microscopy, and inductively coupled plasma spectroscopy techniques.

Cu-Ag powder having Core-Shell structure was prepared from by electroless plating method using agents such as , , Hydroquinone. Ag coated copper powders were analyzed using scanning electron microscopy(SEM) and energy dispersive X-ray spectrometer(EDX). The silver coating layer of copper powder was affected from various reaction conditions such as molar ratio of , , and pulp density. Free silver was generated below 0.1M or 0.3M and above of mole ratio. Silver coating layer thickened as addition of . When the pulp density reached 12% with 0.2M , and 0.15M at , silver was homogeneously distributed around the copper particles and free silver particles were not generated.

Silver nanoparticles (SNPs) at 1 mg/l inhibited the growth of the toxic cyanobacterium, Microcystis aeruginosa, by 87%. Similar results were obtained in field experiments. M. aeruginosa was more sensitive to SNPs than were green algae. SNPs may be a useful selective biocidal agent for the control of M. aeruginosa.

The self-propagating high temperature synthesis approach was applied to synthesize amorphous boron nanopowders in argon atmospheres. For this purpose, we investigated the characteristics of a thermally induced combustion wave in the B2O3 + α Mg system(α = 1.0-8.0) in an argon atmospheres. In this study, the exothermic nature of the B2O3-Mg reaction was investigated using thermodynamic calculations. Experimental study was conducted based on the calculation data and the SHS products consisting of crystalline boron and other compounds were obtained starting with a different initial molar ratio of Mg. It was found that the B2O3 and Mg reaction system produced a high combustion temperature with a rapid combustion reaction. In order to regulate the combustion reaction, NaCl, Na2B4O7 and H3BO3 additives were investigated as diluents. In an experimental study, it was found that all diluents effectively stabilized the reaction regime. The final product of the B2O3 + α Mg system with 0.5 mole Na2B4O7 was identified to be amorphous boron nano-powders(< 100 nm).