Extensive progress and improvements have been made in the science and technology of gamma titanium aluminide alloys within the last decade. In particular, our understanding of their microstructural characteristics and property/microstructurc relationships has been substantially deepened. Based on these achievements, various engineering two-phase gamma alloys have been developed and their mechanical and chemical properties have been assessed. Aircraft and automotive industries arc pursuing their introduction for various structural components. At the same time, recent basic studies on the mechanical properties of two-phase gamma alloys, in particular with a controlled lamellar structure have provided a considerable amount of fundamental information on the deformation and fracture mechanisms of the two-phase gamma alloys. The results of such basic studies are incorporated in the recent alloy and microstructure design of two-phase gamma alloys. In this paper, such recent advances in the research and development of the two-phase gamma alloys and industrial involvement are summarized.

Gamma Titanium Aluminide Alloys

Lasers and Coherent Light Sources

This study, supported by the European Communities, was carried out within the framework of the European Fusion Development Agreement. The views and opinions expressed herein do not necessarily reflect those of the European Commission. a series of studies within the European fusion programme, summarised in References 1 and 2, examined the safety, environmental and economic potential of fusion power. These studies showed that: • Fusion power has very promising potential to provide inherent safety and favourable environmental features, to address global climate change and gain public acceptance. In particular, fusion energy has the potential of becoming a clean, zero-CO 2 emission and inexhaustible energy source. • The cost of fusion electricity is likely to be comparable with that from other environmentally responsible sources of electricity generation. In the period since these earlier studies, there have been substantial advances in the understanding of fusion plasma physics and in the development of more favourable plasma operating regimes, and progress in the development of materials and technology. Accordingly, it was decided to undertake a comprehensive power plant conceptual design study, updated in the light of our current know-how and understanding, to serve as a better guide for the further evolution of the fusion development programme. The European Power Plant Conceptual Study (PPCS) has been a 3-years study, between mid 2001 and mid 2004, of conceptual designs for commercial fusion power plants. It focussed on four power plant models, named PPCS A to PPCS D, which are illustrative of a wider spectrum of possibilities. These span a range from relatively near-term concepts, based on limited technology and plasma physics extrapolations, to a more advanced conception. All four PPCS plant models differ substantially in their plasma physics, electrical output, blanket and divertor technology from the models that formed the basis of the earlier European studies. They also differ substantially from one another in their size, fusion power and materials compositions, and these differences lead to differences in economic performance and in the details of safety and environmental impacts. This report summarizes the European Power Plant Conceptual Study (PPCS), which continued and expanded earlier European fusion power plant studies [1]. The study was carried out with the help of a large number of experts from both the European fusion research community and its industrial partners. All four of the plant models PPCS A to D are based on the tokamak concept as the main line of …

A conceptual study of commercial fusion power plants, EFDA-RP-RE-5.0

Based on recent progress in world tokamak research, the prospects of continuous operation of a tokamak fusion power reactor are discussed. Efficient steady state operation (Q>30) becomes feasible when a large fraction of the plasma current (>70%) is driven by the bootstrap current. Moderate current (Ip approximately 10-20 MA) and an enhanced confinement mode of operation are the key for efficient steady state operation. High magnetic fields (Bt=8-11T) and high Troyon factors ( beta N>3.5) are required to attain high beta p operation and a reasonably high fusion power density. Control of the current and edge pressure profiles is necessary for high beta N operation with a high bootstrap fraction. It is proposed that the Next Step Tokamak should be optimized for continuous operation as well as high current pulsed operation.

https://iopscience.iop.org/article/10.1088/0741-3335/35/SB/003/pdf

Prospects of a stationary tokamak reactor

The first lasing at around 590 nm of a free-electron laser (FEL) in the storage ring NIJI-IV was achieved on August 18, 1992, though just above threshold. The NIJI-IV is a racetrack-type ring dedicated to FEL, which was completed in December 1990. Though the ring is compact, it has two 7.25-m straight sections. The electron beam was stacked for the first time in February 1991. After a 6.3-m optical klystron was installed in one of the straight sections, FEL related experiments were started at the end of April this year, and oscillation experiments have been carried out since the beginning of August. The electron-beam energy during the lasing was about 240 MeV, and the current was 1.1−0.2 mA/bunch. The laser wavelength ranged from 594.5 to 588.7 nm, and the bandwidth was below 0.4 nm.

First lasing of the NIJI-IV storage-ring free-electron laser

Preliminary Design of a Solid Particulate Cooled Blanket for the Steady State Tokamak Reactor (SSTR)

The first lasing of the KHI FEL device installed at the FEL-SUT was obtained at 9 μm on July 6, 2000. The FEL device consists of a 40 MeV accelerator, a beam transport system with two 25° bending magnets, an undulator of 40 periods and 32 mm period length, and a cavity mirror system. The output power was 10 5 times that of the spontaneous emission. The tuning range of the cavity length is about 12 μm.

First lasing of KHI FEL device at the FEL-SUT

We have constructed a racetrack-type compact electron storage ring “NIJI-IV” for UV FEL experiments. The ring has a hexagonal configuration with a circumference 29.6 m. consisting of the two-cell structure of the triple-bend achromat lattice. The length of the straight section is 7.25 m in which a 6.3 m insertion device can be installed. A stored current higher than 200 mA is expected. The first storage of electrons was achieved on February 15, 1991, with an injection energy of 270 MeV. At present, a stored current higher than 70 mA with a lifetime of 20 to 30 min is obtained at full bunch operation (the harmonic number is sixteen).

Present status of a 500 MeV compact electron storage ring for UV FEL experiments

PROBLEM TO BE SOLVED: To provide a safe X-ray theraputic and diagnostic device capable of detecting and treating even a small affected part, which is economically reduced in size as it can be set even in a hospital. SOLUTION: In this X-ray diagnostic device, an X-ray shielding metal complex taken by a subject 7 is selectively accumulated in the affected part, and X-ray from X-ray generators 1 and 2 are radiated thereto to form the X-ray image of the affected part in a radiographic device 6. A metal target 3 for generating a characteristic X-ray belonging to an energy range such that the SN ratio of the X-rays reaching the radiographic device 6 is about 50 or more, the contrast of the X-ray transmitted by the metal complex accumulated in the affected part and the subject 7 is about 2% or more, and the X-ray energy is 40 keV or more is used, and the characteristic X-ray generated by colliding the electron beam generated in an electron generator 1 and accelerated by an electron accelerator 2 to the metal target 3 is used as irradiating X-ray.

X-ray diagnostic device and x-ray theraputic device

PROBLEM TO BE SOLVED: To provide a safety gate having an X-ray inspection apparatus for obtaining a clear X-ray image without damming the flow of people, without making them aware of the inspection apparatus, and by surely stopping the flow at the inspection position. SOLUTION: The safety gate, having the X-ray inspection apparatus has an image display that is provided at the entrance of a region where people enter, and displays a passage 21 having an exit obstacle 22 for preventing people from passing at the exit side, the combination of an X-ray generator 24 and an X-ray image pickup apparatus 25, while pinching a specific photographing position 26 at the passage, and the detection result of the X-ray image pickup apparatus in images, thus performing the X-ray photographing of the entire body of a person 5, standing at the photographing position of the passage to detect goods that are prohibited to be carried in and the person wears, and enables people to enter by removing the exit obstacle 22 when no prohibited goods are detected. COPYRIGHT: (C)2004,JPO

Hidenori Miura

Papers

Preliminary Design of a Solid Particulate Cooled Blanket for the Steady State Tokamak Reactor (SSTR)

First lasing of KHI FEL device at the FEL-SUT

Present status of a 500 MeV compact electron storage ring for UV FEL experiments

X-ray diagnostic device and x-ray theraputic device

Safety gate having x-ray inspection apparatus