Divalent europium-doped nitride phosphors, Ca 1-x Eu x AlSiN 3 (x ) 0-0.2), were successfully prepared by the self-propagating high-temperature synthesis (SHS) by using Ca 1-x Eu x AlSi alloy powder as a precursor. The Rietveld refinement analysis was carried out on the CaAlSiN 3 host lattice to elucidate the luminescence properties of dopant Eu 2+ on the tetrahedrally coordinated site. For the Eu 2+ doped samples, strong absorption peaking at about 460 nm was observed on the excitation spectra, which matched perfectly with the current blue light of InGaN/GaN light-emitting diodes (LEDs). The optimized sample, Ca 0.98 -Eu 0.02 AlSiN 3 , gave the red emission peaking at 649 nm of which the intensity was competitive with the sample prepared from the metal nitride raw materials (Ca 3 N 2 , AlN, Si 3 N 4 , and EuN). The CIE chromaticity index (0.647, 0.347) with high color saturation indicated that it was a promising candidate as a redemitting phosphor for the InGaN/GaN-based down-conversion white LEDs for general illumination or displays.

In 1998, after six years of joint work originally foreseen under the ITER engineering design activities (EDA) agreement, a design for ITER had been developed fulfilling all objectives and the cost target adopted by the ITER parties in 1992 at the start of the EDA. While accepting this design, the ITER parties recognized the possibility that they might be unable, for financial reasons, to proceed to the construction of the then foreseen device. The focus of effort in the ITER EDA since 1998 has been the development of a new design to meet revised technical objectives and a cost reduction target of about 50% of the previously accepted cost estimate. The rationale for the choice of parameters of the design has been based largely on system analysis drawing on the design solutions already developed and using the latest physics results and outputs from technology R&D projects. In so doing the joint central team and home teams converge towards a new design which will allow the exploration of a range of burning plasma conditions. The new ITER design, whilst having reduced technical objectives from its predecessor, will nonetheless meet the programmatic objective of providing an integrated demonstration of the scientific and technological feasibility of fusion energy. Background, design features, performance, safety features, and R&D and future perspectives of the ITER design are discussed.

We have developed a new oxide-based phosphor Ca 3 Sc 2 Si 3 O 12 :Ce 3+ , which is applicable as a green-emitting color converter for white light emitting diodes ͑LEDs͒. This phosphor absorbs blue light around 450 nm and emits green luminescence, with a peak wavelength around 505 nm. It is a promising candidate for application in LEDs as quenching of the phosphor at 150°C was smaller than that of Y 3 Al 5 O 12 :Ce yellow phosphor. A white LED with high color rendering was fabricated by combining this phosphor with a blue GaN LED and a red phosphor. The luminescence of this phosphor is derived from the 5d-4f transition of the Ce ion and the luminescence decay curve fit a single exponential function. This phosphor has a garnet-type host crystal structure. X-ray absorption fine structure analysis showed that Ce ions replaced the Ca position of the host crystal as Ce 3+ .

The focus of effort in ITER EDA since 1998 has been on the development of a new design to meet revised technical objectives and a cost reduction target of about 50% of the previously accepted cost estimate. Drawing on the design solutions already developed, and using the latest physics results and outputs from technology R&D projects, the Joint Central Team and Home Teams, working together, have been able to progress towards a new design which will allow the exploration of a range of burning plasma conditions, with a capacity to progress towards possible modes of steady state operation. The new ITER design, whilst having reduced technical objectives from those of its predecessor, will nonetheless meet the programmatic objective of providing an integrated demonstration of the scientific and technological feasibility of fusion energy. The main features of the current design and of its projected performance are introduced and the outlook for construction and operation is summarized.