The magnetoresistance of single-crystal graphite has been measured at low temperatures in pulsed high magnetic fields up to 52 T applied parallel to the c axis. Many features were found in the high-field phase after the field-induced electronic phase transition. After the sharp rise at the phase transition, the resistance shows a dramatic decrease with increasing field, indicating the reentrant character of the phase boundary. The phase transition was no longer observed at the elevated temperature of 10.8 K in a field up to 48 T. Fine structures consisting of local maxima and an inflection point were observed in the high-field phase. Although the temperature dependence of the critical field is qualitatively in accord with Yoshioka and Fukuyama s charge-density-wave model, a more detailed theory is required to explain most of the present observation.

, "Underwater three-dimensional imaging laser sensor with 120-deg wide-scanning angle using the combination of a dome lens and coaxial optics," Opt. Eng. Abstract. We developed an underwater three-dimensional (3-D) imaging sensor using a 532-nm laser. The sensor system combines a dome lens with coaxial optics to realize a wide-scanning angle of 120 deg ðhorizontalÞ × 30 deg ðverticalÞ while having a compact size of 25-cm diameter and 60-cm length. A detector sensitivity time control circuit and a time-to-digital converter are used to detect a small signal and suppress the unwanted backscattered signals due to marine snow. 3-D imaging of the seafloor with 20-m width and 60-m length was demonstrated in the sea around Ishigaki Island, Japan.

A simple method of constructing a multilayer wire-wound pulse magnet was developed by using ice with woven-glass cloth as a reinforcement spacer. Employing strong copper-wire embedded with Nb-Ti filaments, magnetic fields up to 58 T were generated within an 18 mm bore-diameter with a pulse duration of about 8 ms. Even with soft copper-wire, magnetic fields of over 45 T were produced. The advantages of this method are: easy construction of the magnet, without any troublesome processes such as epoxy impregnation or high-pressure solidification; fast cooling time after a large current discharge; recovery from fatigued insulation after multiple use by a process of warming up the magnet once to room temperature and cooling it again to liquid nitrogen temperature, forming a new ice binder for the woven-glass fibre.

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