Using the solid-state ceramic route, Ca 4 La 2 Ti 5Àx (Mg 1/3 Nb 2/3 ) x O 17 (0 x 4) ceramics were prepared, and the phase purity, microstructure, and microwave dielectric properties were investigated. The XRD results suggest the formation of solid solutions for all studied compositions (0 x 4) and the unit cell volume increases linearly with x. The SEM results also show no evidence of secondary phase and doping (Mg 1/3 Nb 2/3 ) at Ti site promotes the grain growth. The e r of sintered ceramics decreases from 71.86 to 35.23, the Q 3 f value increases from 15 070 to 21 277 GHz and the τ f value varies from 125.2 to À16.7 ppm/°C with x increasing from 0 to 4. A near-zero τ f (~1.62 ppm/°C) is achieved at x = 3 with e r~4 0.45 and Q 3 f~19 123 GHz.

New dielectric ceramics are prepared by the conventional solid-state ceramic route. Effects of LZB glass on sintering, phase purity, microstructure, and dielectric properties of Li 2 ZnTi 3 O 8 ceramics have been investigated. Adding LZB lowers sintering temperature from 1050°C to 875°C, and does not induce much degradation of dielectric properties. The 1.0 wt% LZB glass-added ceramic has better properties of e r = 23.9, Q 9 f = 31,608 GHz, τ f = À14.3 ppm/°C. Additions of TiO 2 markedly improve microwave properties. Typically, the Li 2 ZnTi 3 O 8 + 1 wt%LZB + 3.5 wt%TiO 2 sintered at 900°C shows e r = 26.1, Q 9 f = 45,168 GHz, τ f = À4.1 ppm/°C. Compatibility with Ag electrode indicates that this material may be applied to LTCC devices.

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A novel nitrate- and selenite reducing bacterium strain ZYKT was isolated from a rice paddy soil in Dehong, Yunnan, China. Strain ZYKT is a facultative anaerobe and grows in up to 150, 000 ppm O2. The comparative genomics analysis of strain ZYKT implies that it shares more orthologues with B. subtilis subsp. subtilis NCIB 3610T (ANIm values, 85.4–86.7%) than with B. azotoformans NBRC 15712T (ANIm values, 84.4–84.7%), although B. azotoformans NBRC 15712T (96.3% 16S rRNA gene sequence similarity) is the closest Bacillus species according to 16S rRNA gene comparison. The major cellular fatty acids of strain ZYKT were iso-C14:0 (17.8%), iso-C15:0 (17.8%), and C16:0 (32.0%). The polar lipid profile consisted of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and an unidentified aminophospholipid. Based on physiological, biochemical and genotypic properties, the strain was considered to represent a novel species of the genus Bacillus, for which the name Bacillus oryziterrae sp. nov. is proposed. The type strain is ZYKT (=DSM 26460T =CGMCC 1.5179T). Strain ZYKT can reduce nitrate to nitrite and ammonium and possesses metabolic genes for nitrate reduction including nar, nap and nrf. Biogenic selenium nanoparticles of strain ZYKT show a narrow size distribution and agree with the gaussian distribution. These selenium nanoparticles show significant dose-dependent inhibition of the lung cancer cell line H157, which suggests potential for application in cancer therapy.

The Y 2.9 Ce 0.1 Al 5 O 12 (YAG: Ce 3+ ) phosphors were successfully prepared via molten salt synthesis (MSS) method using the eutectic mixtures of NaNO 2 -KNO 2 or NaCl-KCl as the flux. Using NaCl-KCl as the flux, Y 3 Al 5 O 12 phase is formed above 1000°C, and the as-prepared YAG: Ce 3+ phosphor with 2 lm average particle size has good emission and excitation spectra. Using NaNO 2 -KNO 2 as the flux, Y 3 Al 5 O 12 phase can be formed at a temperature as low as 400°C, but the as-prepared YAG: Ce 3+ phosphor with 200 nm average particle size do not have obvious emission and excitation spectra, and after being annealed at 1100°C, the powder also has 200 nm average particle size but has stronger emission and excitation spectra. Compared with the commercial YAG: Ce 3+ phosphor, the emission intensity of the phosphor prepared by MSS using NaNO 2 -KNO 2 as the flux followed by calcination is a little low, but the latter has a smaller particle size, which will reduce the amount of phosphors utilized in white light-emitting diodes.