Patents by Inventor Yukio Hemmi

Yukio Hemmi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7346140
    Abstract: A photocatalytic substance having the properties of an n-type semiconductor is deposited on a surface of a metal base made of a stainless steel or Inconel. When necessary, the hydrogen concentration of the reactor water is increased. A current produced by the photocatalytic substance when the same is irradiated with light or radioactive rays in a nuclear reactor flows through the metal base to reduce corrosion current. When necessary, the photocatalytic substance is provided on its surface with at least one of Pt, Rh, Ru and Pd.
    Type: Grant
    Filed: June 27, 2005
    Date of Patent: March 18, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Nagayoshi Ichikawa, Yukio Hemmi, Tetsuo Oosato, Junichi Takagi, Kenji Yamazaki
  • Patent number: 7027549
    Abstract: Migration of radioactive materials from a pressure vessel to a steam system in a nuclear power plant is suppressed by using a dryer (3) provided with corrugated plates (22) having surfaces coated with an inorganic ion-exchange material stable under a condition in which high-temperature water exist, such as TiO2.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: April 11, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yukio Hemmi, Shuji Seki, Yutaka Uruma, Minoru Kobayashi, Fumihiko Ishibashi, Ichiro Inami, Takao Baba
  • Publication number: 20060050833
    Abstract: A photocatalytic substance having the properties of an n-type semiconductor is deposited on a surface of a metal base made of a stainless steel or Inconel. When necessary, the hydrogen concentration of the reactor water is increased. A current produced by the photocatalytic substance when the same is irradiated with light or radioactive rays in a nuclear reactor flows through the metal base to reduce corrosion current. When necessary, the photocatalytic substance is provided on its surface with at least one of Pt, Rh, Ru and Pd.
    Type: Application
    Filed: June 27, 2005
    Publication date: March 9, 2006
    Inventors: Nagayoshi Ichikawa, Yukio Hemmi, Tetsuo Oosato, Junichi Takagi, Kenji Yamazaki
  • Patent number: 6940939
    Abstract: A photocatalytic substance having the properties of an n-type semiconductor is deposited on a surface of a metal base made of a stainless steel or Inconel. When necessary, the hydrogen concentration of the reactor water is increased. A current produced by the photocatalytic substance when the same is irradiated with light or radioactive rays in a nuclear reactor flows through the metal base to reduce corrosion current. When necessary, the photocatalytic substance is provided on its surface with at least one of Pt, Rh, Ru and Pd.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: September 6, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Nagayoshi Ichikawa, Yukio Hemmi, Tetsuo Oosato, Junichi Takagi, Kenji Yamazaki
  • Publication number: 20050117690
    Abstract: A method for controlling water quality in a nuclear reactor comprises a first and second steps. The first step is to make an amount of iron, which is carried into the nuclear reactor and corrosively eluted from structural material within the nuclear reactor into reactor water, at least twice as much as any one of an amount of nickel, which is carried into the nuclear reactor, and an amount of nickel, which is generated in the nuclear reactor. The second step is to limit an upper limit of concentration value of iron in system water supplied into the nuclear reactor to up to 0.10 ppb.
    Type: Application
    Filed: November 18, 2004
    Publication date: June 2, 2005
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yukio Hemmi, Kenji Yamazaki, Hajime Hirasawa
  • Patent number: 6856665
    Abstract: A method for controlling water quality in a nuclear reactor comprises a first and second steps. The first step is to make an amount of iron, which is carried into the nuclear reactor and corrosively eluted from structural material within the nuclear reactor into reactor water, at least twice as much as any one of an amount of nickel, which is carried into the nuclear reactor, and an amount of nickel, which is generated in the nuclear reactor. The second step is to limit an upper limit of concentration value of iron in system water supplied into the nuclear reactor to up to 0.10 ppb.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: February 15, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yukio Hemmi, Kenji Yamazaki, Hajime Hirasawa
  • Publication number: 20020057755
    Abstract: Migration of radioactive materials from a pressure vessel to a steam system in a nuclear power plant is suppressed by using a dryer (3) provided with corrugated plates (22) having surfaces coated with an inorganic ion-exchange material stable under a condition in which high-temperature water exist, such as TiO2.
    Type: Application
    Filed: March 30, 2001
    Publication date: May 16, 2002
    Inventors: Yukio Hemmi, Shuji Seki, Yutaka Uruma, Minoru Kobayashi, Fumihiko Ishibashi, Ichiro Inami, Takao Baba
  • Publication number: 20020039399
    Abstract: A method for controlling water quality in a nuclear reactor comprises a first and second steps. The first step is to make an amount of iron, which is carried into the nuclear reactor and corrosively eluted from structural material within the nuclear reactor into reactor water, at least twice as much as any one of an amount of nickel, which is carried into the nuclear reactor, and an amount of nickel, which is generated in the nuclear reactor. The second step is to limit an upper limit of concentration value of iron in system water supplied into the nuclear reactor to up to 0.10 ppb.
    Type: Application
    Filed: September 28, 2001
    Publication date: April 4, 2002
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yukio Hemmi, Kenji Yamazaki, Hajime Hirasawa