Hydrotalcite-type anionic clays: Preparation, properties and applications.

https://zirconia.typepad.com/files/zirconia-as-a-ceramic-biomaterial---piconi---biomaterials-1999.pdf

Zirconia as a ceramic biomaterial

The production of clean and renewable hydrogen through water splitting using photocatalysts has received much attention due to the increasing global energy crises. In this study, a high efficiency of the photocatalytic H2 production was achieved using graphene nanosheets decorated with CdS clusters as visible-light-driven photocatalysts. The materials were prepared by a solvothermal method in which graphene oxide (GO) served as the support and cadmium acetate (Cd(Ac)2) as the CdS precursor. These nanosized composites reach a high H2-production rate of 1.12 mmol h–1 (about 4.87 times higher than that of pure CdS nanoparticles) at graphene content of 1.0 wt % and Pt 0.5 wt % under visible-light irradiation and an apparent quantum efficiency (QE) of 22.5% at wavelength of 420 nm. This high photocatalytic H2-production activity is attributed predominantly to the presence of graphene, which serves as an electron collector and transporter to efficiently lengthen the lifetime of the photogenerated charge carrier...

/pdf/highly-efficient-visible-light-driven-photocatalytic-5a6myaeooj.pdf

Highly efficient visible-light-driven photocatalytic hydrogen production of CdS-cluster-decorated graphene nanosheets.

Phosphor-converted white light-emitting diodes (pc-WLEDs) are emerging as an indispensable solid-state light source for the next generation lighting industry and display systems due to their unique properties including but not limited to energy savings, environment-friendliness, small volume, and long persistence. Until now, major challenges in pc-WLEDs have been to achieve high luminous efficacy, high chromatic stability, brilliant color-rending properties, and price competitiveness against fluorescent lamps, which rely critically on the phosphor properties. A comprehensive understanding of the nature and limitations of phosphors and the factors dominating the general trends in pc-WLEDs is of fundamental importance for advancing technological applications. This report aims to provide the most recent advances in the synthesis and application of phosphors for pc-WLEDs with emphasis specifically on: (a) principles to tune the excitation and emission spectra of phosphors: prediction according to crystal field theory, and structural chemistry characteristics (e.g. covalence of chemical bonds, electronegativity, and polarization effects of element); (b) pc-WLEDs with phosphors excited by blue-LED chips: phosphor characteristics, structure, and activated ions (i.e. Ce 3+ and Eu 2+ ), including YAG:Ce, other garnets, non-garnets, sulfides, and (oxy)nitrides; (c) pc-WLEDs with phosphors excited by near ultraviolet LED chips: single-phased white-emitting phosphors (e.g. Eu 2+ –Mn 2+ activated phosphors), red-green-blue phosphors, energy transfer, and mechanisms involved; and (d) new clues for designing novel high-performance phosphors for pc-WLEDs based on available LED chips. Emphasis shall also be placed on the relationships among crystal structure, luminescence properties, and device performances. In addition, applications, challenges and future advances of pc-WLEDs will be discussed.

Phosphors in phosphor-converted white light-emitting diodes: Recent advances in materials, techniques and properties

http://www.ibmc.up.pt/projectos/FJMonteiro/Bonamidi%20Project/References%20Bonamidi/Denry%20-%20State%20of%20the%20art%20zirconia%20dental%20applications.pdf

State of the art of zirconia for dental applications

Preparation and electrical properties of LixM1-xO (M = Ni, Co)

The behaviour of the removal of the sulfuroxyanions, SO2−4, S2O2−3, S2O2−6 and S4O2−6, in aqueous solutions by Mg0.61Al0.26□0.13O (□:vacancy) was investigated at 40–80°C. All the sulfuroxyanions were removed from solution competitively with OH− to form the hydrotalcite-like compounds. The rate of the removal was first order with respect to the concentration of the sulfuroxyanion in the solution, and the apparent activation energy was about 60 kJ mol−1. All the sulfuroxyanions intercalated in the interlayer of hydrotalcite structure decomposed to SO2−4 at 100–300°C.

Removal of sulfuroxyanions by magnesium aluminium oxides and their thermal decomposition

Thermal-shock fracture behavior of yttria-doped tetragonal zirconia polycrystals (Y-TZP) of various grain sizes was evaluated by the quenching method using water as the quenching solvent. The tetragonal-to-monoclinic phase transformation behavior of Y-TZP around cracks introduced by thermal stress was investigated by using Raman microprobe spectroscopy. The critical quenching temperature difference (ΔTc) of Y-TZP ceramics increased from 250° to 425°C with increasing grain size of zirconia from 0.4 to 3.0 μm, while the fracture strength decreased from 900 to 680 MPa. The improvement of ΔTc of Y-TZP with increasing grain size of zirconia corresponded with the quantity of tetragonal-to-monoclinic phase transformation around cracks introduced by thermal stress.

Grain‐Size Dependence of Thermal‐Shock Resistance of Yttria‐Doped Tetragonal Zirconia Polycrystals

https://www.jstage.jst.go.jp/article/jcersj1950/94/1085/94_1085_133/_pdf

Masahiko Shimada

Papers

Preparation and electrical properties of LixM1-xO (M = Ni, Co)

Removal of sulfuroxyanions by magnesium aluminium oxides and their thermal decomposition

Grain‐Size Dependence of Thermal‐Shock Resistance of Yttria‐Doped Tetragonal Zirconia Polycrystals

Corrosion of SiC, Si3N4 and AIN in molten K2SO4K2CO3 salts

CrN single-crystal growth using Cr–Ga–Na ternary melt