Patents by Inventor Seizi Takeuchi

Seizi Takeuchi 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: 5625332
    Abstract: A superconducting wire comprising a conductor core composed of an oxide superconducting material and a sheath material composed of conductive metal formed at periphery of the conductor core, characterized in that the sheath material is a composite metal including dispersed non-superconductive metallic oxide therein. In accordance with the present invention, oxide superconducting wire having a large mechanical strength, and controllable electric conductivity and thermal conductivity at an arbitrary range corresponding to its using object can be provided.
    Type: Grant
    Filed: May 10, 1994
    Date of Patent: April 29, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Tomoichi Kamo, Keiji Fukushima, Seizi Takeuchi
  • Patent number: 5545610
    Abstract: An oxide-based superconductor ccmprising Tl, Pb, Sr, Ca and Cu or Tl, Pb, Ba, Sr, Ca and Cu, prepared by subjecting a low melting point composition comprising the superconductor-constituting elements and a solid composition comprising the superconductor-constituting elements, prepared in advance, to reaction under melting conditions for the low melting point composition, has distinguished current pass characteristics in a high magnetic field due to improvement of electric contact among grains through reduction of non-superconductor phase, increase in crystal grain sizes (reduction of crystal boundaries), orientation of crystal and cleaning of crystal boundaries.
    Type: Grant
    Filed: September 2, 1993
    Date of Patent: August 13, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Kazutoshi Higashiyama, Toshiya Doi, Takesi Ozawa, Seizi Takeuchi, Tomoichi Kamo, Shinpei Matsuda, Yutaka Yoshida
  • Patent number: 5510323
    Abstract: An oxide superconductor comprising a perovskite type oxide compound of thallium, strontium, calcium and copper or thallium, strontium, balium, calcium and copper is produced by absorbing thallium in a gaseous phase into a mixture of strontium oxide or strontium oxide and barium oxide, calcium oxide, and copper oxide or a mixture of compounds capable of producing these oxides upon firing. From this superconductor are provided a superconductor wire material, tape-shaped wire material, coil, thin film, magnet, magnetic shielding material, printed circuit board, measuring device, computer, power storing device and etc.
    Type: Grant
    Filed: April 7, 1995
    Date of Patent: April 23, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Tomoichi Kamo, Seizi Takeuchi, Shinpei Matsuda, Atsuko Soeta, Takaaki Suzuki, Yutaka Yoshida
  • Patent number: 5502029
    Abstract: Superconductors using oxide superconducting materials having pinning centers inside crystal grains are enhanced in transmissible critical current density and allowed to have a high critical current density even in the magnetic field. A superconductor is produced comprising superconducting materials having a high irreversible magnetic field where the c axes of their crystals are oriented in one direction. This can be practically realized by heat-treating a superconducting material having the composition (Tl.sub.1-X1-X2 Pb.sub.X1 Bi.sub.X2)(Sr.sub.1-X3 Ba.sub.X3).sub.2 Ca.sub.2 Cu.sub.3 O.sub.9+X4 together with Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.8 having a tendency of growing in the form of plate crystal. Various apparatuses capable of working under cooling with liquid nitrogen let alone with liquid helium and having a high superconducting critical current density even in a high magnetic field can be produced.
    Type: Grant
    Filed: January 26, 1994
    Date of Patent: March 26, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Toshiya Doi, Atsuko Soeta, Seizi Takeuchi, Tomoichi Kamo, Shinpei Matsuda
  • Patent number: 5300482
    Abstract: This invention provides an oxide superconductor having a composition of the following general formula of (Tl.sub.a Bi.sub.b Pb.sub.c).sub.x (Sr.sub.d Ba.sub.e).sub.2y (Ca.sub.f Ln.sub.g).sub.y(n-1) Cu.sub.wn O.sub.2n+3+.delta., wherein Ln is at least one selected from Y and rare earth elements, n is 2, 3 or 4, -1<.delta.1, 0.8.ltoreq.x.ltoreq.1.2, 0.8.ltoreq.y.ltoreq.1.2, 0.8.ltoreq.z.ltoreq.1.2 and 0.8.ltoreq.w.ltoreq.1.2, and if a, b and c all are not zero, i.e., greater than zero, a+b+c=1, d+e=1 and f+g=1, and 0<a.ltoreq.1, 0<b.ltoreq.1, 0<c.ltoreq.1, 0.ltoreq.d.ltoreq.1, 0.ltoreq.e.ltoreq.1, 0.3.ltoreq.f.ltoreq.0.99 and 0.01.ltoreq.g.ltoreq.0.7; if b is zero, a+b+c=1, d+e=1 and f+g=1, and 0<a.ltoreq.1, 0<c.ltoreq.1, 0<d<1, 0<e<1, 0.3.ltoreq.f.ltoreq.0.99 and 0.01.ltoreq.g.ltoreq.0.7; if c is zero, a+b+c=1, d+e=1 and f+g=1, and 0<a.ltoreq.1, 0<b.ltoreq.1, 0.ltoreq.d.ltoreq.1, 0.ltoreq.e.ltoreq.1, 0.3.ltoreq.f.ltoreq.0.99 and 0.01.ltoreq.g.ltoreq.0.
    Type: Grant
    Filed: March 1, 1991
    Date of Patent: April 5, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Toshiya Doi, Takaaki Suzuki, Yutaka Yoshida, Atsuko Soeta, Tomoichi Kamo, Seizi Takeuchi
  • Patent number: 4643957
    Abstract: In a fuel cell comprising a pair of counterposed gas-diffusible electrodes, an electrolyte-retaining, porous matrix provided between and in contact with the electrodes, a fuel chamber for feeding a gaseous fuel to the anode of the pair of the electrodes and an oxidizing agent chamber for feeding a gaseous oxidizing agent to the cathode of the pair of the electrodes, the cell performance is remarkably prevented from lowering by making the electrolyte saturated absorption amount of the cathode smaller than that of the anode, thereby preventing migration of the electrolyte in the electrolyte-retaining matrix.
    Type: Grant
    Filed: April 11, 1985
    Date of Patent: February 17, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Seizi Takeuchi, Tomoichi Kamo, Tatsuo Horiba, Kunko Kitami, Toshikatsu Mori, Toshiki Kahara, Jinichi Imahashi, Akio Honji, Masato Takeuchi, Kohki Tamura
  • Patent number: 4623415
    Abstract: In a fuel cell comprising an electrolyte-retaining matrix interposed between a pair of gas-diffusion electrodes, the matrix comprises particles or fibers of a substance unreactive with phosphoric acid and having electron-insulating properties and an inorganic binder.
    Type: Grant
    Filed: January 18, 1985
    Date of Patent: November 18, 1986
    Assignees: Hitachi, Ltd., Hitachi Chemical Co., Ltd.
    Inventors: Toshiki Kahara, Shinpei Matsuda, Kenzo Ishii, Seizi Takeuchi, Jinichi Imahashi, Akio Honji
  • Patent number: 4578112
    Abstract: Disclosed is a catalytic reaction process in which a substance in a liquid reaction system is catalytically reacted with a gaseous substance which is hardly soluble in the liquid reaction system in the presence of a solid catalyst of a non-electroconductive, hydrophobic polymeric material, a part of the surface of which is non-compatible with the liquid reaction system or with the liquid reaction system and a product formed by the catalytic reaction.According to this process, mild reaction conditions can be selected and adopted and separation or recovery of the catalyst can be remarkably facilitated. This catalytic reaction process can be applied to various liquid-gas reactions and can be applied especially advantageously to oxidation and reduction of organic substances and inorganic ions for disposal of waste waters and recovery of valuable substances.
    Type: Grant
    Filed: May 2, 1983
    Date of Patent: March 25, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Toshikatsu Mori, Seizi Takeuchi, Shimpei Matsuda, Teruo Kumagi, Akira Kato, Hisao Yamashita, Masato Takeuchi
  • Patent number: 4529671
    Abstract: In a fuel cell comprising an electrolyte-retaining matrix interposed between a pair of gas-diffusion electrodes, the matrix comprises particles or fibers of a substance unreactive with phosphoric acid and having electron-insulating properties and an inorganic binder.
    Type: Grant
    Filed: September 2, 1982
    Date of Patent: July 16, 1985
    Assignees: Hitachi, Ltd., Hitachi Chemical Co., Ltd.
    Inventors: Toshiki Kahara, Shinpei Matsuda, Kenzo Ishii, Seizi Takeuchi, Jinichi Imahashi, Akio Honji
  • Patent number: 4493879
    Abstract: A fuel cell comprising a pair of gas diffusion electrodes, an electrolyte retaining matrix disposed between said gas diffusion electrodes, and a phosphoric acid electrolyte disposed within said matrix, characterized by using as matrix that comprising one or more metal oxides having electronic insulation and insolubility in phosphoric acid and a binder is excellent in phosphoric acid retaining ability and can be used for a long period of time without degradation of the performance of fuel cell.
    Type: Grant
    Filed: March 11, 1982
    Date of Patent: January 15, 1985
    Assignees: Hitachi, Ltd., Hitachi Chemical Company, Ltd.
    Inventors: Toshiki Kahara, Shimpei Matsuda, Kenzo Ishii, Seizi Takeuchi, Jinichi Imahashi, Akio Honji
  • Patent number: 4457987
    Abstract: A liquid fuel cell including an anode made of carbon powders, which contains therein an electrode catalyzer and is adapted to be supplied with a liquid fuel, a cathode supplied with oxygen, and a separator interposed between the anode and the cathode. In order to improve cell performance, the anode is formed from carbon powders bonded with a binder, the carbon powders having particle sizes passing through a 50 Tyler mesh screen, in which at least thirty percent by volume of the carbon powders are unable to pass through a 100 Tyler mesh screen.
    Type: Grant
    Filed: September 17, 1982
    Date of Patent: July 3, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Tatsuo Horiba, Seizi Takeuchi, Kohki Tamura, Go Kawamura, Tetsuichi Kudo
  • Patent number: 4446210
    Abstract: A fuel cell electrode being substantially free from cracks on the surface of catalyst layer on the electrode and having a good electrode performance under the atmospheric pressure or under pressure when assembled into a fuel cell, which comprises a gas-diffusing electroconductive substrate with continued pores and a water-repellent catalyst layer comprising electroconductive submicron particles having a catalyst, electroconductive materials each having a volume 10.sup.3 -10.sup.10 as large as the volume of the largest particle of the submicron particles and, if necessary, having a catalyst, and a water-repellent polymer as a binder, the electroconductive submicron particles and the electroconductive materials being provided in a mixing ratio by volume of the former to the latter of 95-50 to 5-50.
    Type: Grant
    Filed: April 8, 1982
    Date of Patent: May 1, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Hideo Okada, Jinichi Imahashi, Seizi Takeuchi, Sigeru Okabe, Toshiki Kahara, Kenzo Ishii, Masato Takeuchi, Shimpei Matsuda, Kohki Tamura, Hiroshi Tobita
  • Patent number: 4409129
    Abstract: Disclosed is a method of manufacturing a catalyst composed of fine metal particles having a large specific surface area, such as a platinum black catalyst. According to this method, a solution containing a platinum ion and at least one metal ion or complex ion having an oxidation-reduction potential different from that of platinum is reduced, and the metal having an oxidation-reduction potential different from that of platinum is dissolved out from the precipitated particles. The catalyst obtained according to this method has a very fine particle size and is suitable for an electrode of a fuel cell.
    Type: Grant
    Filed: October 19, 1981
    Date of Patent: October 11, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Seizi Takeuchi, Shimpei Matsuda
  • Patent number: 4407905
    Abstract: Fuel cell with improved and stabilized electrode performance having at least one gas diffusion electrode, where the gas diffusion electrode comprises an electronconductive, gas-permeable substrate and an electrode catalyst uniformly distributed on the substrate, the electrode catalyst comprising colonies each consisting of not more than 20 primary particles of noble metal each having a size of 10-30 A and being uniformly distributed and deposited on carrier powder.
    Type: Grant
    Filed: October 14, 1981
    Date of Patent: October 4, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Seizi Takeuchi, Kenzo Ishii, Toshiki Kahara, Jinichi Imahashi, Masato Takeuchi, Hideo Okada, Sigeru Okabe, Shimpei Matsuda, Fumito Nakajima, Hirosi Tobita, Kohki Tamura
  • Patent number: 4282092
    Abstract: An inorganic particulate adsorbent of a titania-alumina system for treating a superheated water containing radioactive materials such as cobalt ions, which is free from release of corrosive impruities, and which has a high adsorption capacity of radioactive materials and a high mechanical strength is prepared by hydrolyzing a titanium alkoxide and an aluminum alkoxide, thereby forming a hydrous titanium oxide and a hydrous aluminum oxide, respectively; precalcining the hydrous titanium oxide and aluminum oxide, mixing and molding the resulting titania and alumina into a particulate mixture thereof having a titania mole fraction of 0.2-0.9, and calcining the particulate mixture at 500.degree.-700.degree. C. This absorbent is effectively used in treating boiling water-type nuclear reactor core-circulating water to remove radioactive substances therefrom.
    Type: Grant
    Filed: October 1, 1979
    Date of Patent: August 4, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Kazunori Fujita, Shigeo Uno, Seizi Takeuchi, Hisao Yamashita