Fabrication of PbO-Type Structure β-FeSe Superconductor Ceramics by Solid State Reaction Method

PbO-type structure β-FeSe superconductor ceramic were successfully prepared by solid state sinter method in high vacuum state. The structures of the ceramics were investigated by X-ray diffraction and scanning electron microscopy. X-ray diffraction indicates that the sample prepared by two-steps method exhibited a much improved crystallinity. And as sintering temperature increases to 700°C, secondary phase Fe7Se8 phase peak disappear and α-Fe peak weakened. Besides, the ceramic prepared in 700°C exhibited a denser surface morphology in comparison to that prepared in 410°C and its composition is closer to the chemical formula FeSe according to EDX compositional analyses. It was noted that the resistivity of the sample, sintered at 700°C using two-steps sinter method, shows a linear metallic behavior from room temperature and onset is around T = 7.5 K.

Yttrium Oxide Luminescence Films Preparated by Electrodeposition- Sinter Method

Luminescence film material plays a very important role in display technology. In this paper, electrochemical deposition of luminescent Y2O3:Eu or Y2O3:Tb thin films on transparent conducting optically ITO glass substrates by cathodes reduction of yttrium nitric was investigated. Y(OH)3 deposits were obtained using a conventional three electrode cell that potential of work electrode was –1.2v vs. Ag/AgCl electrode for 400 s in a 0.1mol/L Y(NO)3 with 4%(mol/mol) Eu(NO)3 at 65°C.Then this glass was sintered for 2h at 500°C.The luminescence spectrum of the film prepared by this method was tested. Its luminescent spectrum is the same as that of powder which prepared by solid method. Its XRD confirmed the formation of Y2O3 and SEM revealed uniformity of film.

Recovery of Al and Na Values from Red Mud by BaO-Na2CO3Sinter Process

The red mud BaO-Na2CO3sinter process can be used in combination with the Bayer process to recover sodium and aluminium from the red mud waste and direct it back to the process stream. This is facilitated by the high temperature reaction of BaO-Na2CO3and De-silication product (Sodalite) (DSP) in the red mud to produce an insoluble di-barium silicate, barium titanate, barium ferrite and a soluble sodium aluminate. A variation of the red mud BaO-Na2CO3sintering process using half the barium oxide of existing methods has been investigated. The barium to silicon ratio was reduced from 2 to 1 producing a sodium barium silicate (Na2BaSiO4) rather than the di-barium silicate (Ba2SiO4) insoluble phase produced in the existing BaO-Na2CO3sinter method. Synthetic BaO-Na2CO3sinter products were investigated to understand the phases produced during sintering at varying temperatures and the chemistry of extraction. The target phases and morphological behaviors of sinter products were seen in XRD and SEM and the highest extractions were produced from a sinter temperature of 1000 °C for 4 h. A two-stage (105 °C / 60 min, 105 °C / 240 min) water or caustic leaching process was found to be most effective for extraction. Sodium and aluminium extractions were 99% and 99.5% respectively. The experimental method devised was then used to treat red mud and the target phases were produced. An extraction of sodium and aluminium of 94% and 87% respectively was achieved. Silicon extractions were below 2%. Production benefits include sodium hydroxide savings, liquor burning, increased aluminium extraction and reduced cost of waste handling.

The Study of Manufacture of the New Type Coal Ash Ceramsite and Treating Landscape Waste Water with the New Type Coal Ceramsite

Coal ash, clay, coal powder and special type additive used to produce new type coal ash ceramsite by the sinter method. Effects of fly ash/clay/coal powder/special type additive ratio and calcinations temperature and calcinations time on compression strength and water holding capacity of the granules were studied. The best project is using a mixture of fly ash 80%, clay 10%, coal powder 5% and special type additive 5% produced by 30 min of sintering at 1150 . The results of landscape tiny pollute wastewater experiments show the wipe off rates of COD, NH3-N and P are above 80%, 60% and 70% separately.

Preparation Process Optimization and Characterization of an Ultra-Hard Al-Mg-B Material

The Al-Mg-B polycrystalline bodies were prepared using vacuum hot-pressing sinter method by pure Al, Mg and B powders. Process parameters and constitution variation were investigated to obtain compact Al-Mg-B sintered body with high mechanical properties. Al-13%Mg-72.7%B(weight ratio) sintered body prepared under 1600°C, 30MPa for 1 hour in vacuum was proved to be optimum, which bending strength was 156MPa and Vickers hardness was 2220. X-ray diffraction (XRD), Micron Probe Micro-analyzer (EPMA) were employed to analyse the ultimate phases. The results showed that the matrix phases were metal borides including AlB12, MgB6 and AlMgB14, while Al2O3 and MgAl2O4 phases existed which connected or filled in the matrix grains to promote the compactness degree, where oxygen introduced from impurities in raw materials. A portion of Mg in AlMgB14 combined with oxygen during heating to 1600°C which helped to form MgAl2O4 and AlB12 in the end.