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Hirokazu Sasaki

Publications and source records attributed to Hirokazu Sasaki.

4 recordsLinked to original sources

Effect of TiO2 powder addition on sonochemical destruction of 1,4-dioxane in aqueous systems.

Effects of TiO(2) powder addition on sonochemical destruction of 1,4-dioxane in water were investigated through comparison of a SiO(2) powder that had similar specific surface area. Results show that addition of TiO(2) is more effective for decomposition of 1,4-dioxane in water than addition of SiO(2). The contribution of photocatalytic destruction through sonoluminescence is not a dominant mechanism for acceleration of sonochemical reactions by adding TiO(2). Sonication of TiO(2)-added water generated thermally excited holes in this case. Moreover, intrinsic oxygen vacancies in TiO(2) surface play an important role in achieving high decomposition efficiency by producing cavitation. The addition of reduced TiO(2) powder increases both the ultrasonication energy that is consumed in water and the destruction efficiency of 1,4-dioxane.

Journal Article↗

Remote support for emergency medicine using a remote-control laser pointer.

We have developed a laser pointing system, the GestureLaser, which allows a remote operator to control a videocamera and a laser beam via a networked personal computer. The laser spot can be moved by the mouse cursor controlled by the remote instructor. The system was tested by giving remote instruction in thoracentesis to inexperienced operators using a training mannekin. Seven medical students received instructions using the laser pointer and another seven received instruction without the laser pointer. All operators completed the task correctly. The laser pointer group correctly identified the centesis space and performed the task on the first trial. When the laser pointer was not used, four operators (57%) made a mistake in selecting the centesis space at the first trial. The mean times for both stage 1--verbal versus GestureLaser 59 s (SD 13) versus 44 s (SD 5), p = 0.015 - and stage 2--verbal versus GestureLaser 98 s (SD 20) versus 64 s (SD 7), P = 0.002 - were significantly shorter when the GestureLaser was used. The study shows that the laser pointing system can be used to remotely instruct a novice operator in performing thoracentesis. It could improve collaboration between geographically separated sites.

Abdominal Wall↗

Specimen preparation for high-resolution transmission electron microscopy using focused ion beam and Ar ion milling.

We have developed a focused ion beam (FIB)-Ar ion-milling technique for high-resolution transmission electron microscopy. A micrometresized specimen was mounted on a cross section of metal foil of a few micrometres thick, using FIB microsampling. Following this, a 2 degrees wedgeshaped part was made in the specimen using FIB. Finally, the specimen was milled using an Ar ion beam to remove the FIB-damaged layers. We applied the FIB-Ar ion milling technique to a CeO(2)/Gd(2)Zr(2)O(7) multilayer specimen, resulting in the crystal lattice fringes of both layers being clearly observable in comparison to a specimen finished using a Ga ion beam at an accelerating voltage of 10 kV.

Argon↗