In a series of experiments on a demolition system using a steam pressure cracking（SPC）agent were conducted. The results were obtained by drilling 11 mm diameter（D10 class）rebar in concrete using three types of rake angle bits at the tip of a small rock drill with a power of 2.24 kW （Compressed Air power）. The rebar could be pierced by the rock drill a time of 730～1020 seconds. Thus, it was confirmed that it is possible to process holes for SPC for concrete demolition with reinforcing bars. However, a drilling speed of rebar was about one-fi ftieth of concrete. Observing the steel chips, there are two types of drilling mechanisms. One is a drilling mechanism in which the rebar undergoes compressive deformation at the tip of the bit, and microscopic chips are discharged at the tip of the bit with each impact. The chips are not more than 1 mm wide. The second is to discharge macro chips of several millimeters in size, and the entire rebar is subjected to compressive deformation and because of multiple impacts from the end of the rebar, drilling proceeds in steps.

A coaxial ultrasonic transducer was proposed for non-destructive evaluation using sidebands. The coaxial probe was consisted of a ring-type piezoelectric transducer and a disk-type piezoelectric transducer. The sound field distribution of the displacement was numerically calculated by the finite element method when the ratio of the inner diameter of the ring type vibrator to the diameter of the disk type vibrator was changed. In addition, two-frequency ultrasonic waves were transmitted from the coaxial transducer toward a closed-crack located inside the solid, and the sideband components contained in the transmitted waves were detected using the pulse inversion method. It was confi rmed that the proposed coaxial transducer could generate sidebands in a sound field with a closed crack.

An α"-Fe₁₆N₂ has very high magnetic crystalline anisotropy energy even if magnetic anisotropy field is not so large because of its very high saturation magnetization. Therefore, magnetization switching field of this material is smaller than that of L1₀-FePt which has very high magnetic crystalline anisotropy energy due to having very high magnetic anisotropy field. As the results, α"-Fe₁₆N₂ seems one of the suitable materials for next-generation high density magnetic recording media without energy assisted recording system. In this study, for fabrication of α"-Fe₁₆N₂ thin fi lms, we newly attempted a pulsed DC（P-DC） reactive sputtering method, which is expected to provide high quality in the formation of oxide/nitride thin films with complex crystal structures. Since there have been no attempts to fabricate this thin fi lms with this method before, we investigated the influence of film properties （composition） on deposition parameters such as pulse frequency, deposition power, and target-substrate （T-S） distance, and fi nally optimized the deposition conditions to obtain the nitrogen concentration of Fe:N ＝ 16:2 in the film. As a result, with decreasing pulse frequency, with increasing deposition power, and with decreasing T-S distance, nitrogen concentration in the thin fi lm decreased, and it was clear that the optimized deposition conditions to obtain the nitrogen concentration of Fe:N ＝ 16:2 in the thin fi lm were pulse frequency: 25 kHz, deposition power: 200 W, and T-S distance: 100 mm, respectively. Using these deposition conditions, we investigated the deposition temperature and VHF plasma irradiation power to promote the α" phase formation and crystallization in the fabrication of Fe-N thin films on MgO（100） single crystalline substrates. As a result, it was found that α" phase formation and crystallization were most enhanced at a deposition temperature of 200 ℃ and a VHF plasma irradiation power of 3 W （V_dc: -18 to -16 V）. The usefulness of P-DC power source for fabrication of α"-Fe₁₆N₂ thin fi lms was confi rmed by comparing to Fe-N thin fi lms fabricated by using a DC power source. As a result, reactive P-DC sputtering method was found to have a positive impact on α" phase formation and crystallization.

Rice bran wax（RBW）formed gels with long-chain alcohols（from 1-hexanol to 1-decanol）. The gelation property of RBW was evaluated using Hansen solubility parameters. It was speculated that the main driving force for gel formation of RBW is van der Waals forces between RBWs due to moderate solvophobic effects from the gelling solvent. FT-IR spectra and powder XRD measurements of xerogels prepared from 1-heptanol indicated that the alkyl chains of RBW were arranged in trans-form and had a close-packed structure. Gel melting point measurements indicated that the gelation of RBW was characteristic of supramolecular gels in which entropy loss was compensated by enthalpy.