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A series of samples of the system Ni0.65Zn0.35CuxFe2−xO4 (x=0, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) are prepared by the usual ceramic technique. X-ray analysis shows that they are cubic spinel (single phase). The lattice parameter, theoretical density (D x), bulk density (D) and the porosity (P) are measured for the samples. The vacancy concentration of oxygen is an important parameter in the sintering process of spinel ferrites. The decrease in the population of Fe3+ ion in the octahedral sites with the introduction of Cu2+ results in the decrease of lattice parameter. The DTA tracing shows a strong exothermic peak at 90°C.

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An ion chromatographic method has been developed for the determination of traces of Li+, Na+, K+, Ca2+, Mg2+, Sr2+, Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, Mn2+ in UO2, ThO2 powders and sintered (Th,U)O2 pellets. This new method utilizes poly-(butadiene-maleic acid) (PBDMA) coated silica cation exchange column and mixed functionality column of anion and cation exchange to achieve the separation of alkali, alkaline earths and transition metal ions, respectively. It involves matrix separation after sample dissolution by solvent extraction with TBP (tri butyl phosphate)-TOPO (tri octyl phosphine oxide)/CCl4. Interference of transition metal ions in the determination of alkali, alkaline earth metal ions are removed by using pyridine 2,6-dicarboxylic acid (PDCA) in the tartaric acid mobile phase. Mobile phase composition is optimized for the base line separation of alkali, alkaline earth and transition metal ions. Linear calibration graphs in the range 0.01–20 μg mL−1 were obtained with regression coefficients better than 0.999. The respective relative standard deviations were also determined. Recoveries of the spiked samples are within ±10% of the expected value. The developed method is authenticated by comparison with certified standards of UO2 and ThO2 powders.

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IGCC slag is a vitreous residual product from the new induction gasification combined cycle gasification thermal power plants. In order to characterize this waste as secondary new material for the production of new glasses and glass-ceramics as construction materials; this slag from the Puertollano, Ciudad Real, Spain power plants has been fully thermally investigated. After controlled heating this waste gives rise to hematite, anorthite, and cristobalite crystallized materials.

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The results of experiments on application of NaH2PO4 as a binding agent for ceramic kaolin samples were presented. The experiments were carried out at temperatures of 973, 1073 and 1173 K and NiO and CoO additives were used as tempering agents. The parameters of the obtained samples with NaH2PO4 were compared with the samples compressed with water only. The materials of 3-4 times higher bending strength, lower water absorption as well decreased open porosity were prepared during these experiments. The binding function of the NaH2PO4 additive relies on creation of some compounds in reaction between the products of its condensation and products of kaolin decomposition. Finally a ceramic material of prospective properties was created.

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The optical transmittance — temperature spectra of well-translucent thin pellets of hydroxyapatite prepared by the high isostatic pressure consolidation of xerogel particles were measured by a newly-developed thermal analysis technique. From these spectra, it was possible to identify temperature intervals with increased or decreased levels of light transmittance, clearly associated with microstructural changes. The thermal processing of treated pellets was stopped at temperatures deliberately chosen with respect to the specific transmittance states. Samples with increased transparency were prepared when the heating of pellets was stopped at the temperatures of the locally highest light transmittance measured.

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