Nippon Steel Corporation

Tokyo Shibaura Denki Kabushiki Kaisha

Showa Denko Kabushiki Kaisha

Tokyo Denryoku Kabushiki Kaisha

Kunio Takahashi

Norio Koike

Koichi Sato

Yasushi Matsui

Eiichi Haginomori

Shinichi Menju

Hiroshi Matsue

Yoichi Murakami

Kenichiro Minami

Eiichi Zaima

Osamu Kiyomiya

Water area structure using placing member for underwater ground

Lepidocrocite (.gamma.-FeOOH) with an large specific surface area and a uniform particle size is provided by a method comprising preparing a suspension of ferrous hydroxide at a pH of 6.5 to 7.5 by adding a ferrous salt solution with an alkali solution in an amount of 0.4 to 0.7 times the theoretical amount for converting all the ferrous salt to ferrous hydroxide, blowing an oxygen-containing gas into the suspension to form a seed crystal of .gamma.-FeOOH, completing the generation reaction of .gamma.-FeOOH by blowing an oxygen-containing gas into the suspension while adding an alkali solution to keep the pH of the suspension within a range of 3 to 5, in which an Si concentration of the suspensions for seed reaction and for generation reaction of .gamma.-FeOOH is controlled to be within 5 to 30 ppm.

Method for manufacturing lepidocrocite

In a method for detecting foreign matters present in gas sealed electrical apparatus including a tank at the ground potential and containing an insulating gas and a high voltage live part disposed in the tank, a voltage is applied to the high voltage live part causing generation of ultrasonic waves and the ultrasonic waves propagated through the tank is sensed by a sensing element mounted on the tank.

Method and apparatus for detecting foreign matters in gas sealed

Growing community of inventors

Yokohama, Japan

Kunio Takahashi