Patents by Inventor Yoichi Wada

Yoichi Wada 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).

  • Publication number: 20090225928
    Abstract: The object of this invention is to provide a method for mitigating a stress corrosion cracking of reactor structural material which makes it possible to suppress the rise in the main steam line dose rate without secondary effects such as a rise in the concentration of radioactive cobalt-60, etc. in the reactor water. Hydrogen and a reductive nitrogen compound containing nitrogen having a negative oxidation number (for example, hydrazine) are injected into the core water of boiling water nuclear power plant. By injecting the reductive nitrogen compound containing nitrogen having a negative oxidation number into the core water, the stress corrosion cracking of structural material of reactor can be mitigated without side reactions such as a rise in the concentration of cobalt-60, etc.
    Type: Application
    Filed: January 16, 2009
    Publication date: September 10, 2009
    Inventors: Kazushige ISHIDA, Yoichi Wada, Makoto Nagase, Masahiko Tachibana, Masao Endo, Motomasa Fuse, Naoshi Usui, Motohiro Aizawa
  • Publication number: 20090190712
    Abstract: The object of this invention is to provide a method for mitigating a stress corrosion cracking of reactor structural material which makes it possible to suppress the rise in the main steam line dose rate without secondary effects such as a rise in the concentration of radioactive cobalt-60, etc. in the reactor water. Hydrogen and a reductive nitrogen compound containing nitrogen having a negative oxidation number (for example, hydrazine) are injected into the core water of boiling water nuclear power plant. By injecting the reductive nitrogen compound containing nitrogen having a negative oxidation number into the core water, the stress corrosion cracking of structural material of reactor can be mitigated without side reactions such as a rise in the concentration of cobalt-60, etc.
    Type: Application
    Filed: February 2, 2009
    Publication date: July 30, 2009
    Inventors: Kazushige ISHIDA, Yoichi Wada, Makoto Nagase, Masahiko Tachibana, Masao Endo, Motomasa Fuse, Naoshi Usui, Motohiro Aizawa
  • Publication number: 20090185653
    Abstract: A method of suppressing deposition of radionuclides on components of a nuclear power plant comprises forming a ferrite film by contacting a first chemical including iron (II) ions, a second chemical for oxidizing the iron (II) ions to iron (III) ions, and a third chemical for adjusting the pH of a processing solution containing a mixture of the first and second chemicals to be 5.5 to 9.0 with the metal member surface in a time period from a finishing stage in decontamination step of removing contaminants formed on the surface of metal member composing the nuclear power plant, and suppressing deposition of radionuclides on the metal member by the ferrite film.
    Type: Application
    Filed: March 25, 2009
    Publication date: July 23, 2009
    Applicant: Hitachi-GE Nuclear Energy, Ltd.
    Inventors: Hideyuki HOSOKAWA, Makoto NAGASE, Kazushige ISHIDA, Yoichi WADA, Naoshi USUI, Motohiro AIZAWA, Motomasa FUSE
  • Publication number: 20090141849
    Abstract: A method of suppressing deposition of radionuclides on components of a nuclear power plant comprises forming a ferrite film by contacting a first chemical including iron (II) ions, a second chemical for oxidizing the iron (II) ions to iron (III) ions, and a third chemical for adjusting the pH of a processing solution containing a mixture of the first and second chemicals to be 5.5 to 9.0 with the metal member surface in a time period from a finishing stage in decontamination step of removing contaminants formed on the surface of metal member composing the nuclear power plant, and suppressing deposition of radionuclides on the metal member by the ferrite film.
    Type: Application
    Filed: February 3, 2009
    Publication date: June 4, 2009
    Applicant: HITACHI-GE NUCLEAR ENERGY, LTD.
    Inventors: Hideyuki HOSOKAWA, Makoto Nagase, Kazushige Ishida, Yoichi Wada, Naoshi Usui, Motohiro Aizawa, Motomasa Fuse
  • Publication number: 20090137030
    Abstract: An input section of an incubator accepts, from a user, a first input selecting a specified incubation container which registers an observing schedule, and a second input specifying an imaging condition of the specified incubation container in an observing sequence. A calculating section calculates, according to the above-mentioned imaging condition, an observing duration of the specified incubation container from a first data relating to a carrying period of an incubation container and a second data with regard to an imaging duration. A schedule management section extracts, based on a schedule data, a registrable time zone in which an observing sequence of the specified incubation container can be executed without overlapping with previously registered observing schedules, and outputs to display the registrable time zone for presentation to the user.
    Type: Application
    Filed: January 12, 2009
    Publication date: May 28, 2009
    Applicant: NIKON CORPORATION
    Inventor: Yoichi Wada
  • Publication number: 20090003509
    Abstract: A method of suppressing deposition of radionuclides on components of a nuclear power plant comprises forming a ferrite film by contacting a first chemical including iron (II) ions, a second chemical for oxidizing the iron (II) ions to iron (III) ions, and a third chemical for adjusting the pH of a processing solution containing a mixture of the first and second chemicals to be 5.5 to 9.0 with the metal member surface in a time period from a finishing stage in decontamination step of removing contaminants formed on the surface of metal member composing the nuclear power plant, and suppressing deposition of radionuclides on the metal member by the ferrite film.
    Type: Application
    Filed: July 1, 2008
    Publication date: January 1, 2009
    Applicant: Hitachi-GE NUCLEAR ENERGY, LTD.
    Inventors: Hideyuki Hosokawa, Makoto Nagase, Kazushige Ishida, Yoichi Wada, Naoshi Usui, Motohiro Aizawa, Motomasa Fuse
  • Publication number: 20080292042
    Abstract: The object of this invention is to provide a method for mitigating a stress corrosion cracking of reactor structural material which makes it possible to suppress the rise in the main steam line dose rate without secondary effects such as a rise in the concentration of radioactive cobalt-60, etc. in the reactor water. Hydrogen and a reductive nitrogen compound containing nitrogen having a negative oxidation number (for example, hydrazine) are injected into the core water of boiling water nuclear power plant. By injecting the reductive nitrogen compound containing nitrogen having a negative oxidation number into the core water, the stress corrosion cracking of structural material of reactor can be mitigated without side reactions such as a rise in the concentration of cobalt-60, etc.
    Type: Application
    Filed: June 18, 2008
    Publication date: November 27, 2008
    Inventors: Kazushige Ishida, Yoichi Wada, Makoto Nagase, Masahiko Tachibana, Masao Endo, Motomasa Fuse, Naoshi Usui, Motohiro Aizawa
  • Publication number: 20080247499
    Abstract: A handling method for a natural circulation boiling water reactor having a chimney having cylindrical chimney shell disposed above a core in a reactor pressure vessel, a plurality of square tubes disposed in the chimney shell, and a grid support plate with grid holes supporting and in communication with a lower end portion of the square tubes so that adjacent square tubes are disposed at an interval which exceeds the width of one square tube between them. The method includes steps shifting predetermined ones of the square tubes to the interval between the square tubes, and performing maintenance and inspection of members around a core via the grid holes which appear at positions from which the predetermined square tubes are taken out due to the shift of the predetermined square tubes.
    Type: Application
    Filed: June 3, 2008
    Publication date: October 9, 2008
    Inventors: Atsushi WATANABE, Yoichi Wada, Makoto Nagase, Kazushige Ishida, Hideyuki Hosokawa, Fumihito Hirokawa, Masaaki Tsubaki, Shiro Takahashi
  • Publication number: 20080149028
    Abstract: A method of suppressing deposition of radionuclides on components of a nuclear power plant comprises forming a ferrite film by contacting a first chemical including iron (II) ions, a second chemical for oxidizing the iron (II) ions to iron (III) ions, and a third chemical for adjusting the pH of a processing solution containing a mixture of the first and second chemicals to be 5.5 to 9.0 with the metal member surface in a time period from a finishing stage in decontamination step of removing contaminants formed on the surface of metal member composing the nuclear power plant, and suppressing deposition of radionuclides on the metal member by the ferrite film.
    Type: Application
    Filed: May 2, 2007
    Publication date: June 26, 2008
    Applicant: Hitachi, Ltd.
    Inventors: Hideyuki Hosokawa, Makoto Nagase, Kazushige Ishida, Yoichi Wada, Naoshi Usui, Motohiro Aizawa, Motomasa Fuse
  • Publication number: 20070201607
    Abstract: A natural circulation boiling water reactor provides to a chimney with a plurality of tubes. That is to say, each of the plurality of tubes partitions the coolant flow path above a core. Thus, unlike the conventional natural circulation boiling water reactor providing the flow path partition wall grid in which the plate members are made integral by welding and coolant flow paths are partitioned, the chimney of the natural circulation boiling water reactor can reduce the number of welded portions because the edges of the four corners of each flow path do not need to be welded. The natural circulation boiling water reactor can avoid removal as a single unit, as in the case of the flow path partition wall grid in the conventional natural circulation boiling water reactor, by detaching each tube. The chimney can be easily detached from the reactor pressure vessel.
    Type: Application
    Filed: February 28, 2007
    Publication date: August 30, 2007
    Inventors: Atsushi WATANABE, Yoichi Wada, Makoto Nagase, Kazushige Ishida, Hideyuki Hosokawa, Fumihito Hirokawa, Masaaki Tsubaki, Shiro Takahashi
  • Publication number: 20060067455
    Abstract: A method of suppressing deposition of radionuclides on components of a nuclear power plant comprises forming a ferrite film by contacting a first chemical including iron (II) ions, a second chemical for oxidizing the iron (II) ions to iron (III) ions, and a third chemical for adjusting the pH of a processing solution containing a mixture of the first and second chemicals to be 5.5 to 9.0 with the metal member surface in a time period from a finishing stage in decontamination step of removing contaminants formed on the surface of metal member composing the nuclear power plant, and suppressing deposition of radionuclides on the metal member by the ferrite film.
    Type: Application
    Filed: July 15, 2005
    Publication date: March 30, 2006
    Applicant: Hitachi, Ltd.
    Inventors: Hideyuki Hosokawa, Makoto Nagase, Kazushige Ishida, Yoichi Wada, Naoshi Usui, Motohiro Aizawa, Motomasa Fuse
  • Publication number: 20050075521
    Abstract: A method and plant for conversion into oil is provided which can completely heat and decompose a large amount of a plastic raw material, and treat a harmful gas. The plastic raw material is dissolved in a dissolution section (31) to form an expanded plastic. The expanded plastic is sent to an inclined first-stage decomposition column (47) and a second-stage decomposition column (48) adjacent to the first-stage decomposition column, both having fixed temperature distributions, which depolymerize and decompose the plastic into a light secondarily decomposed gas. The extracted secondarily decomposed gas is cooled into oil in condensers (37, 38) and collected in oil storage tanks (42, 43).
    Type: Application
    Filed: January 20, 2003
    Publication date: April 7, 2005
    Inventor: Yoichi Wada
  • Publication number: 20050018805
    Abstract: The object of this invention is to provide a method for mitigating a stress corrosion cracking of reactor structural material which makes it possible to suppress the rise in the main steam line dose rate without secondary effects such as a rise in the concentration of radioactive cobalt-60, etc. in the reactor water. Hydrogen and a reductive nitrogen compound containing nitrogen having a negative oxidation number (for example, hydrazine) are injected into the core water of boiling water nuclear power plant. By injecting the reductive nitrogen compound containing nitrogen having a negative oxidation number into the core water, the stress corrosion cracking of structural material of reactor can be mitigated without side reactions such as a rise in the concentration of cobalt-60, etc.
    Type: Application
    Filed: July 22, 2004
    Publication date: January 27, 2005
    Inventors: Kazushige Ishida, Yoichi Wada, Makoto Nagase, Masahiko Tachibana, Masao Endo, Motomasa Fuse, Naoshi Usui, Motohiro Aizawa
  • Patent number: 6487265
    Abstract: Surfaces of the structural components of a nuclear power plant exposed to reactor water are wetted with an electroless plating solution containing an electrical insulating substance. The electrical insulating substance has a high resistivity about 105 (100000) times those of the structural components of the nuclear power plant or above. A metal film containing the electrical insulating substance is formed on the surfaces of the structural components exposed to the reactor water by wetting the surfaces of the structural components with the electroless plating solution. Thus, the electrochemical corrosion potential of the structural components is reduced regardless of whether hydrogen is injected into the reactor water.
    Type: Grant
    Filed: July 6, 2000
    Date of Patent: November 26, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Masato Nakamura, Yamato Asakura, Yoshiyuki Takamori, Kazuhiko Akamine, Katsumi Ohsumi, Masanori Sakai, Yoichi Wada
  • Publication number: 20020136344
    Abstract: Surfaces of the structural components of a nuclear power plant exposed to reactor water are wetted with an electroless plating solution containing an electrical insulating substance. The electrical insulating substance has a high resistivity about 105 (100000) times those of the structural components of the nuclear power plant or above. A metal film containing the electrical insulating substance is formed on the surfaces of the structural components exposed to the reactor water by wetting the surfaces of the structural components with the electroless plating solution. Thus, the electrochemical corrosion potential of the structural components is reduced regardless of whether hydrogen is injected into the reactor water.
    Type: Application
    Filed: April 29, 2002
    Publication date: September 26, 2002
    Applicant: Hitachi, LTD.
    Inventors: Masato Nakamura, Yamato Asakura, Yoshiyuki Takamori, Kazuhiko Akamine, Katsumi Ohsumi, Masanori Sakai, Yoichi Wada