We captured ultrafast two-dimensional (2D)-burst images of the crystalline-to-amorphous phase transition of Ge2Sb2Te5. These transitions were induced by a femtosecond laser pulse, and the images, with a sub-picosecond temporal resolution, were acquired on a single-shot basis through the change in local optical transmittance. We employed a 2D-burst imaging method of sequentially timed all-optical mapping photography utilizing spectral filtering (SF-STAMP). The SF-STAMP system consists of a 25-beam-generating diffractive optical element, a band-pass filter, and two Fourier transform lenses. We used a frequency-chirped broadband pulse and achieved 25-frame burst imaging with an interval of 133 fs in a single-shot time window of 3.2 ps.

We propose and experimentally demonstrate a new method called SF-STAMP for sequentially timed all-optical mapping photography (STAMP) that utilizes spectral filtering. SF-STAMP is composed of a diffractive optical element (DOE), a band-pass filter, and two Fourier transform lenses. Using a linearly frequency-chirped pulse and converting the wavelength to the time axis, we realize single-shot ultrafast burst imaging. As an experimental demonstration of SF-STAMP, we monitor the dynamics of a laser ablation using a linearly frequency-chirped broadband pulse (>100 nm) that is temporally stretched up to ~40 ps. This imaging method is expected to be effective for investigating ultrafast dynamics in a diverse range of fields, such as photochemistry, plasma physics, and fluidics.

The formation behavior of Secondary Reaction Zone (SRZ) for a 4 th generation nickel-base single crystal (SC) superalloy with aluminide coating was investigated. The growth of SRZ is supposed to be dominantly controlled by the inward diffusion of aluminum from the coating layer to the substrate. The outward diffusion of Ru from the substrate to the coating layer may also contribute to SRZ formation. A remarkable reduction of SRZ was accomplished by depositing thin films composed of Co and/or Ru on the alloy surface prior to aluminide coating, that is expected to restrict the diffusion of Al and Ru between the coating layer and the substrate.

In order to get fundamental understanding to establish a refurbishment technology for advanced gas turbine components, the cellular formation associated with a y/y microstructure coarsened in lamellar or equiaxed arrays in single crystal Ni-base superalloys, CMSX-2 and CMSX-4, have been studied, supposing the case in which they were previously subjected to a damage associated with local plastic deformation, followed by a re-heat treatment. During this study special attention was paid to understand the nucleation and the growth of the transformation from viewpoints of crystallo-plasticity and therm0 dynamics. The experimental evidence indicated that the transformation originated and developed with high anisotropy, being influenced by the following factors: the strain field produced by local plastic deformation, the crystallographic orientation, the re-heat treatment temperature and time, and the microsegregation in the material. It was shown that the transformation was reproduced in material previously subjected to fatigue and thermo-mechanical fatigue damage, in which the shearing of y precipitates resulting from the activation of { 11 l}4fO> slip systems was significant. It was shown that diffusion was controlling the growth rate of the transformation, accompanied with an activation energy of 36 kcal/mol. Furthermore, the effect of the local cellular transformation on the high temperature small fatigue crack propagation was quantified experimentally. supeml10ys 2oc0 Edited byT

Three bacterial strains, identified as Alcaligenes sp. strain D-59 and Pseudomonas sp. strains D-87 and D-186, capable of growing on 2,6-dimethylnaphthalene (2,6-DMN) as the sole source of carbon and energy were isolated from soil samples. 2,6-Naphthalene dicarboxylic acid was formed in the culture broths of these three strains grown on 2,6-DMN. In addition, 2-hydroxymethyl-6-methylnaphthalene and 6-methylnaphthalene-2carboxylic acid were detected in the culture broth of strain D-87. Strain D-87 grew well on 1,2-, 1,3-, 1,4-, 1,5-, 2,3-, and 2,7-DMN as the sole source of carbon and energy and accumulated 2-methylnaphthalene-3-carboxylic acid and 2,3-naphthalene dicarboxylic acid from 2,3-DMN, 4-methylnaphthalene-1-carboxylic acid from 1,4-DMN, and 7-methylnaphthalene-2-carboxylic acid from 2,7-DMN.

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The feasibility study of electroless plating as carbon fiber modification for aluminum matrix composites was carried out. The comparison of Cu plating and Ni plating of carbon fiber by the electroless method was investigated. The Cu- or Ni-coated carbon fiber reinforced aluminum was fabricated with a centrifugal pressure infiltration method. The mechanical property was metallographically discussed. Electroless plating is able to improve the throwing power of the precipitant into the multifilament and uniformly coat Cu or Ni onto the carbon fiber. The technique using centrifugal casting seems to be an innovative method for fabrication of composite materials. The eutectic reaction between aluminum and Cu or Ni on the fiber appears to improve the affinity of the carbon fiber and aluminum. The Cu-plated carbon fiber reinforced aluminum is two times higher in bending strength than Ni-plated carbon fiber reinforced aluminum.

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