Halogen [i.e., Fluorine (fl), Chlorine (cl), Bromine (br), Iodine (i), Astatine (at)] Containing Patents (Class 505/123)
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Patent number: 8703651Abstract: A composition of matter for a layered ionic superconductor comprising a plurality of layers of ions and electronic interaction charges, and having a substantially improved superconducting transition temperature is described. An aspect of the composition includes a first layer comprising a plurality of alkali ions and cesium ions in particular that is adjacent to a second layer comprising a plurality of halogen ions and fluorine ions in particular. The first and second layers contain electronic interaction charges and are separated by a predetermined perpendicular distance. Crystalline structure, ionic properties, superconducting transition temperature, and superfluid density for several embodiments including companion ionic species are described and illustrated. Methods for preparing the several embodiments are provided.Type: GrantFiled: July 6, 2012Date of Patent: April 22, 2014Inventors: Dale Richard Harshman, Anthony Thomas Fiory
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Patent number: 8389045Abstract: An oxide superconductor film formed on a substrate includes an oxide containing at least one metal M selected from the group consisting of yttrium and lanthanoid metals, provided that cerium, praseodymium, promethium and ruthenium are excluded, and barium and copper, in which the film has an average thickness of 350 nm or more, an average amount of residual carbon of 3×1019 atoms/cc or more, and an amount of residual fluorine in a range of 5×1017 to 1×1019 atoms/cc, and in which, when divided the film into a plurality of regions from a surface of the film or from an interface between the film and the substrate, each region having a thickness of 10 nm, atomic ratios of copper, fluorine, oxygen and carbon between two adjacent regions are in a range of ? times to 5 times.Type: GrantFiled: October 7, 2010Date of Patent: March 5, 2013Assignee: Kabushiki Kaisha ToshibaInventor: Takeshi Araki
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Patent number: 8288321Abstract: Provides a new non-oxide system compound material superconductor as an alternative of the perovskite type copper oxides superconductor. Layered compounds which are represented by chemical formula AF(TM)Pn (wherein, A is at least one selected from a group consisting of the second family elements in the long form periodic table, F is a fluorine ion, TM is at least one selected from a group of transition metal elements consisting of Fe, Ru, Os, Ni, Pd, and Pt, and Pn is at least one selected from a group consisting of the fifteenth family elements in the long form periodic table), having a crystal structure of ZrCuSiAs type (space group P4/nmm) and which become superconductors by doping trivalent cations or divalent anions.Type: GrantFiled: July 9, 2009Date of Patent: October 16, 2012Assignee: Japan Science and Technology AgencyInventors: Hideo Hosono, Hiroshi Yanagi, Toshio Kamiya, Satoru Matsuishi, Sungwng Kim, Seok Gyu Yoon, Hidenori Hiramatsu, Masahiro Hirano, Takatoshi Nomura, Yoichi Kamihara
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Patent number: 8124568Abstract: An oxide superconductor with superconduction properties being improved by effectively introducing a pinning center thereinto and its fabrication method are disclosed. The superconductor has a high-crystallinity oxide superconductor film which is formed on a substrate with a <001> direction of crystal grain being oriented almost perpendicularly to the substrate and with (100) planes of neighboring crystal grains being oriented to form an oblique angle ranging from 0 to 4 degrees or 86 to 90 degrees. The film has a multilayer structure including a plurality of high-density magnetic field trap layers stacked in almost parallel to the substrate and a low-density magnetic field trap layer sandwiched therebetween. An average grain boundary width of the high-density trap layers in a cross-section horizontal to the substrate is 80 nm or less. The width is less than an average grain boundary width of the low-density trap layer in its cross-section horizontal to the substrate.Type: GrantFiled: October 1, 2008Date of Patent: February 28, 2012Assignee: Kabushiki Kaisha ToshibaInventors: Mariko Hayashi, Takeshi Araki
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Publication number: 20110237440Abstract: Disclosed is a composition for forming a thick oxide superconductor film, the oxide being an RE-BA-Cu based oxide, wherein RE is at least one element selected from the group consisting of Y, Nd, Sm, Gd, Eu, Yb, Pr, and Ho. The composition contains an RE salt of a keto acid having 4 to 8 carbon atoms as an RE component, barium trifluoroacetate as a Ba component, at least one copper salt selected from the group consisting of a copper salt of a branched saturated aliphatic carboxylic acid having 6 to 16 carbon atoms and a copper salt of an alicyclic carboxylic acid having 6 to 16 carbon atoms as a Cu component, and an organic solvent dissolving these metal salt components. In the composition, the RE to Ba to Cu molar ratio is 1:1.3 to 2.2:2.4 to 3.Type: ApplicationFiled: January 6, 2010Publication date: September 29, 2011Applicant: ADEKA CORPORATIONInventors: Tomotaka Goto, Atsuya Yoshinaka, Akimasa Yajima
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Publication number: 20110172103Abstract: An oxide superconductor film formed on a substrate includes an oxide containing at least one metal M selected from the group consisting of yttrium and lanthanoid metals, provided that cerium, praseodymium, promethium and ruthenium are excluded, and barium and copper, in which the film has an average thickness of 350 nm or more, an average amount of residual carbon of 3×1019 atoms/cc or more, and an amount of residual fluorine in a range of 5×1017 to 1×1019 atoms/cc, and in which, when divided the film into a plurality of regions from a surface of the film or from an interface between the film and the substrate, each region having a thickness of 10 nm, atomic ratios of copper, fluorine, oxygen and carbon between two adjacent regions are in a range of ? times to 5 times.Type: ApplicationFiled: October 7, 2010Publication date: July 14, 2011Inventor: Takeshi Araki
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Publication number: 20110136670Abstract: Compositions are disclosed of a matrix of a high temperature superconductive oxide such as YBCO, with non-superconductive particles distributed in the matrix. The non-superconductive particles comprise at least one rare earth element (RE) and at least one of tantalum (Ta) and niobium (Nb). Of particular interest are non-superconductive particles of composition RE-Ta3O7 (RTO), where RE is Yb, Er, Gd or Sm, disposed in a YBCO superconductive matrix.Type: ApplicationFiled: August 5, 2009Publication date: June 9, 2011Applicant: CAMBRIDGE ENTERPRISE LIMITEDInventors: Sophie-Ann Harrington, Judith Macmanus-Driscoll
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Publication number: 20110111965Abstract: Provides a new non-oxide system compound material superconductor as an alternative of the perovskite type copper oxides superconductor. Layered compounds which are represented by chemical formula AF(TM)Pn (wherein, A is at least one selected from a group consisting of the second family elements in the long form periodic table, F is a fluorine ion, TM is at least one selected from a group of transition metal elements consisting of Fe, Ru, Os, Ni, Pd, and Pt, and Pn is at least one selected from a group consisting of the fifteenth family elements in the long form periodic table), having a crystal structure of ZrCuSiAs type (space group P4/nmm) and which become superconductors by doping trivalent cations or divalent anions.Type: ApplicationFiled: July 9, 2009Publication date: May 12, 2011Applicant: JAPAN SCIENCE AND TECHNOLOGY AGENCYInventors: Hideo Hosono, Hiroshi Yanagi, Toshio Kamiya, Satoru Matsuishi, Sungwng Kim, Seok Gyu Yoon, Hidenori Hiramatsu, Masahiro Hirano, Takatoshi Nomura, Yoichi Kamihara
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Patent number: 7833941Abstract: An oxide superconductor film formed on a substrate includes an oxide containing at least one metal M selected from the group consisting of yttrium and lanthanoid metals, provided that cerium, praseodymium, and promethium are excluded, and barium and copper, in which the film has an average thickness of 350 nm or more, an average amount of residual carbon of 3×1019 atoms/cc or more, and an amount of residual fluorine in a range of 5×1017 to 1×1019 atoms/cc, and in which, when divided the film into a plurality of regions from a surface of the film or from an interface between the film and the substrate, each region having a thickness of 10 nm, atomic ratios of copper, fluorine, oxygen and carbon between two adjacent regions are in a range of ? times to 5 times.Type: GrantFiled: September 18, 2007Date of Patent: November 16, 2010Assignee: Kabushiki Kaisha ToshibaInventor: Takeshi Araki
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Patent number: 7732376Abstract: The present invention relates to a method of preparing an oxide superconducting film, the method includes reacting a metal acetate containing metal M selected from the group consisting of lanthanum, neodymium and samarium with fluorocarboxylic acid having not less than three carbon atoms, reacting barium acetate with fluorocarboxylic acid having two carbon atoms, reacting copper acetate with fluorocarboxylic acid having not less than two carbon atoms, respectively, followed by refining reaction products, dissolving the reaction products in methanol such that a molar ratio of the metal M, barium and copper is 1:2:3 to prepare a coating solution, and coating a substrate with the coating solution to form a gel film, followed by calcining and firing the gel film to prepare an oxide superconducting film.Type: GrantFiled: August 31, 2009Date of Patent: June 8, 2010Assignees: Kabushiki Kaisha Toshiba, International Superconductivity Technology CenterInventors: Takeshi Araki, Koichi Nakao, Izumi Hirabayashi
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Patent number: 7691786Abstract: The present invention relates to a method of preparing an oxide superconducting film, the method includes reacting a metal acetate containing metal M selected from the group consisting of lanthanum, neodymium and samarium with fluorocarboxylic acid having not less than three carbon atoms, reacting barium acetate with fluorocarboxylic acid having two carbon atoms, reacting copper acetate with fluorocarboxylic acid having not less than two carbon atoms, respectively, followed by refining reaction products, dissolving the reaction products in methanol such that a molar ratio of the metal M, barium and copper is 1:2:3 to prepare a coating solution, and coating a substrate with the coating solution to form a gel film, followed by calcining and firing the gel film to prepare an oxide superconducting film.Type: GrantFiled: March 3, 2008Date of Patent: April 6, 2010Assignees: Kabushiki Kaisha Toshiba, International Superconductivity Technology CenterInventors: Takeshi Araki, Koichi Nakao, Izumi Hirabayashi
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Patent number: 7622424Abstract: A method for producing a thick film includes disposing a precursor solution onto a substrate to form a precursor film. The precursor solution contains precursor components to a rare-earth/alkaline-earth-metal/transition-metal oxide including a salt of a rare earth element, a salt of an alkaline earth metal, and a salt of a transition metal in one or more solvents, wherein at least one of the salts is a fluoride-containing salt, and wherein the ratio of the transition metal to the alkaline earth metal is greater than 1.5. The precursor solution is treated to form a rare earth-alkaline earth-metal transition metal oxide superconductor film having a thickness greater than 0.8 ?m. precursor solution.Type: GrantFiled: September 30, 2005Date of Patent: November 24, 2009Assignee: American Superconductor CorporationInventors: Xiaoping Li, Thomas Kodenkandath, Edward J. Siegal, Wei Zhang, Martin W. Rupich, Yibing Huang
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Patent number: 7615515Abstract: An oxide superconductor includes a main component represented by the following formula: LnBa2Cu3O7-x, where Ln comprises two or more types of elements selected from the group consisting of Gd, Tb, Dy, Ho, Er, Tm, and Y, and a content of each element is 10 to 90 mol %, and fluorine at a molar ratio of 10?2 to 10?6 with respect to copper.Type: GrantFiled: September 15, 2005Date of Patent: November 10, 2009Assignees: Kabushiki Kaisha Toshiba, International Superconductivity Technology CenterInventors: Takeshi Araki, Koichi Nakao, Izumi Hirabayashi
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Publication number: 20080274895Abstract: The present invention relates to a method of preparing an oxide superconducting film, the method includes reacting a metal acetate containing metal M selected from the group consisting of lanthanum, neodymium and samarium with fluorocarboxylic acid having not less than three carbon atoms, reacting barium acetate with fluorocarboxylic acid having two carbon atoms, reacting copper acetate with fluorocarboxylic acid having not less than two carbon atoms, respectively, followed by refining reaction products, dissolving the reaction products in methanol such that a molar ratio of the metal M, barium and copper is 1:2:3 to prepare a coating solution, and coating a substrate with the coating solution to form a gel film, followed by calcining and firing the gel film to prepare an oxide superconducting film.Type: ApplicationFiled: March 3, 2008Publication date: November 6, 2008Inventors: Takeshi ARAKI, Koichi Nakao, Izumi Hirabayashi
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Publication number: 20080191561Abstract: A superconducting electrical cable system is configured to be included within a utility power grid. The superconducting electrical cable system includes a superconducting electrical path interconnected between a first and a second node within the utility power grid. A non-superconducting electrical path is interconnected between the first and second nodes within the utility power grid. The superconducting electrical path and the non-superconducting electrical path are electrically connected in parallel. The superconducting electrical path has a lower series impedance, when operated below a critical current level, than the non-superconducting electrical path. The superconducting electrical path has a higher series impedance, when operated at or above the critical current level, than the non-superconductor electrical path.Type: ApplicationFiled: February 9, 2007Publication date: August 14, 2008Inventors: DOUGLAS C. FOLTS, James Maguire, Jie Yuan, Alexis P. Malozemoff
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Publication number: 20080139393Abstract: An oxide superconductor film formed on a substrate includes an oxide containing at least one metal M selected from the group consisting of yttrium and lanthanoid metals, provided that cerium, praseodymium, promethium and ruthenium are excluded, and barium and copper, in which the film has an average thickness of 350 nm or more, an average amount of residual carbon of 3×1019 atoms/cc or more, and an amount of residual fluorine in a range of 5×1017 to 1×1019 atoms/cc, and in which, when divided the film into a plurality of regions from a surface of the film or from an interface between the film and the substrate, each region having a thickness of 10 nm, atomic ratios of copper, fluorine, oxygen and carbon between two adjacent regions are in a range of 1/5 times to 5 times.Type: ApplicationFiled: September 18, 2007Publication date: June 12, 2008Inventor: Takeshi ARAKI
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Patent number: 6673387Abstract: A process is described for formation of oxide films independent of thickness from precursor films comprising metals, metal oxides, and metal fluorides with properties and structures similar to those previously only obtained in thin films, for example less than about 0.4 microns.Type: GrantFiled: July 14, 2000Date of Patent: January 6, 2004Assignee: American Superconductor CorporationInventors: Wei Zhang, Qi Li, Martin W. Rupich
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Publication number: 20020132739Abstract: A superconducting magnesium diboride (MgB2) thin film having c-axial orientation and a method and apparatus for fabricating the same are provided. The fabrication method includes forming a boron thin film on a substrate and thermally processing the substrate on which the boron thin film is formed along with a magnesium source and cooling the resulting structure. The superconducting magnesium diboride thin film can be used in a variety of electronic devices employing superconducting thin films, such as precision medical diagnosis equipment using superconducting quantum interface devices (SQUIDs) capable of sensing weak magnetic fields, microwave communications equipment used for satellite communications, and Josephson devices. Computer systems with 100 times greater computing speed can be implemented with the superconducting magnesium diboride thin film.Type: ApplicationFiled: March 15, 2002Publication date: September 19, 2002Inventors: Won nam Kang, Sung-Ik Lee, Eun-Mi Choi, Hyeong-Jin Kim
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Patent number: 6426320Abstract: A method for fabricating superconductor articles with an epitaxial layer is described. The method can be performed under conditions of relatively high pressure and low substrate surface temperature. The resulting epitaxial layers can demonstrate various advantageous features, including low pore density and/or inclusions with small average particle size diameter.Type: GrantFiled: December 29, 1999Date of Patent: July 30, 2002Assignee: American Superconductors CorporationInventors: Leslie G. Fritzemeier, David M. Buczek
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Patent number: 6027564Abstract: A method for fabricating composite articles with an epitaxial layer is described. The method can be performed under conditions of relatively high pressure and low substrate surface temperature. The resulting epitaxial layers can demonstrate various advantageous properties, such as low pore density and/or inclusions with small average particle size diameter.Type: GrantFiled: January 15, 1998Date of Patent: February 22, 2000Assignee: American Superconductor CorporationInventors: Leslie G. Fritzemeier, David M. Buczek
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Patent number: 6022832Abstract: A method for fabricating superconductor articles with an epitaxial layer is described. The method can be performed under conditions of relatively high pressure and low substrate surface temperature. The resulting epitaxial layers can demonstrate various advantageous features, including low pore density and/or inclusions with small average particle size diameter.Type: GrantFiled: January 15, 1998Date of Patent: February 8, 2000Assignee: American Superconductor CorporationInventors: Leslie G. Fritzemeier, David M. Buczek
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Patent number: 5858926Abstract: The present invention is directed to a process for preparing a HgBaCaCuO superconductor by annealing a precursor mixture comprising a lower member of the homologous HgBaCaCuO superconductor series, a source of calcium and a source of copper. The precursor mixture may further comprise a source of oxygen, a source of rhenium, and, if desired, a source of an additional element selected from the group consisting of halogens and metals other than mercury, barium, calcium, copper and rhenium. The process is particularly effective for preparing (Hg.sub.1-x,Re.sub.x)Ba.sub.2 Ca.sub.2 Cu.sub.3 O.sub.8-y by annealing a precursor mixture containing (Hg.sub.1-x,Re.sub.x)Ba.sub.2 Ca.sub.1 Cu.sub.2 O.sub.6-y at a temperature below about 850.degree. C., wherein x ranges up to about 0.25 and y is a rational number ranging from about negative 1 to about positive 1.Type: GrantFiled: August 23, 1996Date of Patent: January 12, 1999Assignee: Florida State UniversityInventors: Justin Schwartz, Christian H. Wolters, Kathleen M. Amm
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Patent number: 5777032Abstract: An ocular lens obtained by reacting a hydroxyl group-containing polymer shaped to have an ocular lens shape, with a silicon-containing compound of the formula (I):O.dbd.C.dbd.N--R.sup.1 --Si.sub.n O.sub.n-1 (CH.sub.3).sub.2n+1 (I)wherein R.sup.1 is a C.sub.1-6 linear or branched alkylene group, and n is an integer of from 1 to 15.Type: GrantFiled: February 25, 1997Date of Patent: July 7, 1998Assignee: Menicon Co., Ltd.Inventors: Yasuhiro Yokoyama, Yuriko Watanabe, Sadayasu Tanikawa, Shoji Ichinohe, Toshio Yamazaki
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Patent number: 5716907Abstract: The present invention is an oxide superconductor containing alkaline earth metal M (where M is at least one element of Ba, Sr, and Ca) and having a crystalline structure in which a portion based on two rock-salt structures including the alkaline earth metal M, oxygen, and chlorine, and a 2n-1 piece of infinite layer structure portion are alternately layered on each other, said 2n-1 piece of infinite layer structure portion having an atom layer including copper atoms and oxygen atoms in a ratio of 1 to 2 and of an atom layer including only M atoms layered on each other (where n is an integer of 1 or more and where copper atoms and oxygen atom are contained in a ratio of 1 to 2 if n is 1).Type: GrantFiled: March 20, 1996Date of Patent: February 10, 1998Assignees: International Superconductivity Technology Center, The Furukawa Electric Co., Ltd., Tohoku Electric PowerInventors: Tadashi Tatsuki, Seiji Adachi, Makoto Itoh, Toshiyuki Tamura, Changqin Jin, Xiao-Jing Wu, Hisao Yamauchi
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Patent number: 5614471Abstract: A superconductive material is in composition expressed as Y.sub.0.33 Ba.sub.0.67).sub.a Cu.sub.b (OF).sub.c. The usual a, b and c are so selected as to satisfy a relation expression ax (mix valence of A)+bx (mix valence of B)=cx (mix valence of C).Type: GrantFiled: May 25, 1995Date of Patent: March 25, 1997Assignee: Sumitomo Electric Industries, Ltd.Inventors: Kengo Ohkura, Hajime Hitotsuyanagi, Hiromi Takei
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Patent number: 5607658Abstract: A metal oxide manufacturing method includes the steps of preparing the metal oxide expressed by a general formula of AXBYCZDn, (where A represents at least one element selected from a group consisting of a rare earth element, yttrium and an element obtained either by substituting part of rare earth elements with alkali metals or alkali earth metals or by substituting part of yttrium with alkali metals or alkali earth metals, B represents an alkali earth metal, C represents copper or an element obtained by substituting part of copper with transition metals, and D represents oxygen, and where when X=1, Y=2 to 4, Z=2.7 to 6 and n=6 to 13), reducing the metal oxide expressed by the general formula, and halogenating the reduced metal oxide. Part of oxygen (D) of the metal oxide expressed by the general formula is substituted with the halogen elements.Type: GrantFiled: September 5, 1995Date of Patent: March 4, 1997Assignee: Canon Kabushiki KaishaInventors: Norio Kaneko, Tamaki Kobayashi
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Patent number: 5565414Abstract: A metal oxide is provided which is represented by the compositional formula :(Bi.sub.1-x A.sup.I.sub.x).sub.2 (Sr.sub.y Ca.sub.1-y-z A.sup.II.sub.z).sub.p (Cu.sub.1-r A.sup.III.sub.r).sub.q O.sub..delta.wherein 0.ltoreq.x.ltoreq.0.5, 0.3.ltoreq.y.ltoreq.0.7, 0.ltoreq.z.ltoreq.0.5, 0.ltoreq.r.ltoreq.0.1, 1>y+z, 2>p>11, 1.ltoreq.q.ltoreq.10 and 5.4.ltoreq..delta..ltoreq.24 with the exclusion of x=z=r=0, A.sup.I is at least one element selected from In, Sb, Pb and Sn; A.sup.II is at least one element selected from Na, K, Mg, Ba, and Sn and A.sup.III is at least one element selected from Ti, V, Cu, Ni, Zr, Nb, Ta, Fe and Ru. The metal oxide may further comprise an element selected from lanthanoids and yttrium. The metal oxide material shows superconductivity at a temperature not lower than the boiling point of liquid helium.Type: GrantFiled: November 21, 1994Date of Patent: October 15, 1996Assignee: Canon Kabushiki KaishaInventors: Jun Akimitsu, Tohru Den, Fumio Kishi, Norio Kaneko, Masatake Akaike, Kiyozumi Niizuma, Atsuko Tanaka
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Patent number: 5561102Abstract: A superconductive fullerene and a process for making such superconductive fullerene are provided. The process involves contacting a quantity of fullerene with the vapor of an interhalogen compound such as ICl. The halogen doped fullerenes exhibited a transition temperature above 60 K.Type: GrantFiled: December 14, 1994Date of Patent: October 1, 1996Assignee: The Research Foundation of State University of New York at BuffaloInventors: Yi-Han Kao, Liwei Song, Deborah D. L. Chung, Kevin T. Fredette
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Patent number: 5482917Abstract: A superconducting composition having the nominal formula TlM.sub.2 CuO.sub.5-x F.sub.x wherein M is Ba and x is from about 0.10 to about 0.65, or M is Sr and x is from about 0.35 to about 0.75 is disclosed.Type: GrantFiled: September 21, 1993Date of Patent: January 9, 1996Assignee: E. I. du Pont de Nemours and CompanyInventor: Munirpallam A. Subramanian
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Patent number: 5426092Abstract: A thin film, high T.sub.c fluorinated, superconducting having a lattice structure differing from the lattice structure of the material substrate, such as sapphire or stainless steel, upon which it is grown. The superconducting material is characterized by basal plane alignment of the unit cells thereof even though the substrate does not possess a perovskite lattice structure. A laser ablation technique is used to evaporate material from a fluorinated pellet of target material to deposit the fluorinated superconducting material on the substrate. The instant invention provides for a low pressure and relatively low temperature method of depositing a superconducting film which is characterized by (1) a minimal number of high angle grain boundaries typically associated with polycrystalline films, and (2) aligned a, b, and c axes of the unit cells thereof so as to provide for enhanced current carrying capacities.Type: GrantFiled: June 25, 1992Date of Patent: June 20, 1995Assignee: Energy Conversion Devices, Inc.Inventors: Stanford R. Ovshinsky, Rosa Young
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Patent number: 5340792Abstract: A method of substantially aligning the superconducting grains of a multi-grained perovskite defect oxide type material, which material includes at least one superconducting phase. In the superconducting phase of such perovskite materials, the unit cells thereof include a plurality of substantially parallel metal oxide planes spacedly disposed along the c axis thereof. The aforementioned alignment of discrete grains of the multi-grained superconducting material occurs along the c axis.Type: GrantFiled: November 28, 1989Date of Patent: August 23, 1994Assignee: Energy Conversion Devices, Inc.Inventors: Stanford R. Ovshinsky, Rosa Young
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Patent number: 5244871Abstract: An oxide superconductor comprises a composition represented by the composition formula: (Nd.sub.x --Ce.sub.y --L.sub.z).sub.2 CuO.sub.4-d (wherein L is an element selected from Ca and Mg, and x+y+z=1). The compositions of Nd, Ce and L of the oxide superconductor corresponds to a point falling inside an area of Nd--Ce--L ternary diagram surrounded by straight lines (A-B), (B-C), (C-D) and (D-A) connecting point (A) with point (B), point (B) with point (C), point (C) with point (D) and point (D) with point (A), respectively, the points (A), (B), (C) and (D) being points (x=1, y=0, z=0), (x=0.4, y=0.6, z=0), (x=0.4, y=0.3, z=0.3) and (x=0.1, y=0, z=0.9), respectively, in the Nd--Ce--L ternary diagram. Above-described Nd--Ce--L--Cu--O oxides can exhibit superconductivity within a wide range of composition when heat-treated in an atmosphere of nitrogen.Type: GrantFiled: October 9, 1991Date of Patent: September 14, 1993Assignees: Mitsubishi Metal Corporation, Hitachi, Ltd., International Superconductivity Technology CenterInventors: Takeshi Sakurai, Toru Yamashita, Hisao Yamauchi, Shoji Tanaka