Abstract: High T.sub.c superconducting compounds are made by forming a reaction mixture of the oxides of Sr, Cu, Ca and Tl, compressing these into a hardened body, and placing the hardened body into a container. The container is then evacuated and sealed. The hardened body is heated under pressure until the oxides of Sr, Ca, Cu, and Tl react to form a superconducting compound.
Type:
Grant
Filed:
November 8, 1989
Date of Patent:
June 9, 1992
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
William L. Lechter, Michael S. Osofsky, Earl F. Skelton, Louis E. Toth
Abstract: The invention relates to a flaky extender pigment formed by adsorbing a titanium oxide hydrate having a mean grain size of from 0.1 to 0.5 .mu.m on the surface of a flaky substrate and then further coating a titanium oxide hydrate having a mean grain size of less than 0.1 .mu.m.
Type:
Grant
Filed:
January 7, 1991
Date of Patent:
June 2, 1992
Assignee:
Merck Patent Gesellschaft mit beschrankter Haftung
Abstract: An oxalate route coprecipitation process for preparing a superconducting YBaCuO system precursor powder comprises preparing an aqueous solution of nitrates of yttrium, barium and copper, which is then mixed with an organic solution containing a dibasic oxalate ester, an organic base and acetone. An ultrasound vibration is applied to the mixture to coprecipitate oxalates of yttrium, barium and copper. The decomposition of the oxalate ester is enhanced to an optimum rate as the result of the homogeneous phase contributed by acetone which is miscible with both water and the oxalate ester. The ultrasound vibration segregates the precipitate particles thereby preventing the coagulation of the particles and assuring fine and uniform particle size.
Type:
Grant
Filed:
February 20, 1991
Date of Patent:
May 19, 1992
Assignee:
Industrail Technology Research Institute
Abstract: A high temperature superconducting system has the general composition Tl-R-X-Y, wherein: R is a Group 2A element; X is a group 1B element; and Y is a Group 6A element. Preferably, the composition has the following formula Tl-Ba-Cu-O. The high temperature superconductor of the present invention has a transition temperature of about 90 K with the probability of one phase superconducting at a temerature perhaps as high as 270 K. Processes for making the high temperature superconductor are also provided.
Abstract: Improvement in the superconducting transition temperature of superconductive materials which have perovskite structure or similar structure to perovskite such as typically Y-Ba-Cu-O type perovskite compounds is obtained by implanting phosphorus ion in the superconductive materials.
Abstract: A superconducting material and a process for producing a superconducting material comprising a compound oxide represented by the general formula:(Ba, .gamma.).sub.x (.alpha.,.beta.).sub.1 -.sub.x .epsilon..sub.y Cu.sub.1-y O.sub.3-zin which".gamma." represents an element of the IIa group of the periodic table except Ba, and atomic ratio of .gamma. to Ba, being selected in a range between 1% and 90%,".alpha." represents Y or La,".beta." represents an element of the IIIa group of the periodic table but is different from .alpha., an atomic ratio of .beta. to .alpha. being selected in a range between 1 and 90%,".epsilon." represents a metal element of the IIIb group of the periodic table, x, y and z are numbers each satisfies ranges of 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, and 0.ltoreq.z.ltoreq.1 respectively, andthe expression of (Ba, .gamma.) and (.alpha.,.beta.) mean that the respective elements occupy predetermined sites in a crystal in a predetermined proportion.
Abstract: Vanadium-containing superconducting oxides are disclosed having critical temperature (T.sub.c) values of above about 100.degree. K. and preferably about 110.degree.-150.degree. K., together with predicted current density (J.sub.c) values on the order of 10.sup.4 -10.sup.5 amperes/cm.sup.2. The oxides hereof are moreover relatively ductile and easily bulk sintered to give end products having desirable superconductivity characteristics. Certain preferred oxides of the invention are defined by the general formula:(V.sub.1-x M.sub.x).sub.i (A.sub.1-y M.sub.y).sub.j Q.sub.k Cu.sub.m O.sub.r.+-.t I.
Type:
Grant
Filed:
October 1, 1990
Date of Patent:
March 24, 1992
Assignee:
University of Kansas
Inventors:
Kai W. Wong, Wai-Yim Ching, Peter C. W. Fung, Fui T. Chan, Zhengzhi Sheng
Abstract: A superconducting material and a process for producing a superconducting material comprising a compound oxide represented by the general formula:(Ba, .gamma.).sub.x (.alpha.,.beta.).sub.1-x .epsilon..sub.y Cu.sub.1-y O.sub.3-zin which".gamma." represents an element of the IIa group of the periodic table except Ba, an atomic ratio of .gamma. to Ba, being selected in a range between 1% and 90%,".alpha." represents Y or La,".beta." represents an element of the IIIa group of the periodic table but is different from .alpha., and atomic ratio of .beta. to .alpha. being selected in a range between 1 and 90%,".epsilon." represents a metal element of the IIIb group of the periodic table, x, y and z are numbers each satisfies ranges of 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, and 0.ltoreq.z.ltoreq.1 respectively, andthe expression of (Ba, .gamma.) and (.alpha., .beta.) mean that the respective elements occupy predetermined sites in a crystal in a predetermined proportion.
Abstract: An opacifying pigment with enhanced light scattering properties for use as a paper coating or filler material is produced by reacting kaolin in the presence of water with sodium hydroxide or potassium hydroxide at a temperature in excess of 60.degree. C. The kaolin is reacted with the hydroxide in a concentration to produce a molality of at least 0.1.
Type:
Grant
Filed:
April 21, 1989
Date of Patent:
February 18, 1992
Assignee:
Thiele Kaolin Company
Inventors:
Joseph C. S. Shi, Jerry L. Curtis, Timothy L. Salter
Abstract: Stable mixed metal oxide compositions containing nitrogen are formed by treating an oxygen-deficient perovskite composition with nitrogen dioxide. Preferably, the oxygen-deficient perovskite is of the formula X.sub.a Z.sub.b Cu.sub.c O.sub.h wherein X is a member selected from the group consisting of yttrium, scandium, lanthanum, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, bismuth and thallium, Z is a member selected from the group consisting of barium, strontium, calcium, magnesium and mixtures thereof, a is not less than 1, b is from 0 to 3, c is from 0 to 3, and h is not greater than about 6, and the mixed metal oxides are of the formula X.sub.a Z.sub.b Cu.sub.c N.sub.j O.sub.k where X, Z, a, b and c are as previously defined, j is from about 0.001 to about 3, and k is from about 6 to about 13.
Type:
Grant
Filed:
July 8, 1988
Date of Patent:
February 18, 1992
Assignee:
The University of Colorado Foundation, Inc.
Abstract: A high temperature superconductor is provided having meltability. The superconductor has a preferred composition of Tb-R-Ba-Cu-O wherein R is chosen from the group of rare earth metals excluding: Praseudyium; Cerium; and Terbium.
Abstract: An oxide superconductor comprising a matrix of plate crystals of the formula REBa.sub.2 Cu.sub.3 O.sub.7-y wherein RE is at least one member selected from the group consisting of Y, La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu, and y is the amount of oxygen deficiency, oriented and overlaid one on another, and granular crystals of the formula RE.sub.2 BACuO.sub.5 wherein RE is as defined above, insularly dispersed in the matrix in an amount of at least 0.1 mol per mol of the REBa.sub.2 Cu.sub.3 O.sub.7-y crystals.
Abstract: A process of making high-temperature Tl-based superconductors. The process includes the steps of reacting solid Ba-Ca-Cu-oxides with Tl.sub.2 O.sub.3 vapor. The process allows high quality Tl-based superconductors to be easily fabricated.
Abstract: This invention relates to homogeneous copper-containing oxide superconductors with improved superconducting properties and a process for preparing them.
Abstract: A preparation method of bulk YBa.sub.2 Cu.sub.3 O.sub.x superconductors with high transport critical current and critical current density (Jc), wherein x is 7-.delta., obtained by a modified melt-textured growth method. A continuous dc current carrying capacity exceeding 120 A with critical current density, Jc, higher than 37300 A/cm.sup.2 at 77K has been obtained for the prepared superconductor.
Type:
Grant
Filed:
April 27, 1990
Date of Patent:
December 31, 1991
Assignee:
Industrial Technology Research Institute
Abstract: A target used for forming a thin film of a quinary superconductive oxide contains metal copper ranging between about 8% and about 40% by volume dispersed into a quaternary or a quinary complex oxide, and the metal copper improves the thermal conductivity and the electrical conductivity of the target, so that cracks are less liable to take place in the target and the target is applicable to a d.c. sputtering system, thereby decreasing the production cost of the thin film.
Abstract: A new high temperature superconductor with transition temperature above 120 K. is disclosed. The superconductor in a preferrred embodiment comprises TlRBaCuO wherein R is chosen from Group 2A elements excluding Ba. In another preferred embodiment, the superconductor comprises TlSrCuO. Processes for making high temperature superconductors are also disclosed.
Abstract: A method for making metal/ceramic superconductor thick film structures including the steps of preparing a silver/superconductor ink, applying the ink to a substrate, evaporating the ink's binder, decomposing a silver compound in the residue to coat the superconductor grains, sintering the coated superconductor grains, and oxygenating the superconductor grains through the silver coating. The resultant inter-granular silver increases the critical current and mechanical strength of the superconductor.
Type:
Grant
Filed:
October 13, 1989
Date of Patent:
December 10, 1991
Assignee:
Hewlett-Packard Company
Inventors:
John T. Anderson, V. K. Nagesh, Richard C. Ruby
Abstract: A new high temperature superconducting system with transition temperature above 120 K is disclosed. One superconductor in that system in a preferred embodiment comprises TlRBaCuO wherein R is chosen from Group 2A elements excluding Ba. In a preferred embodiment, the superconductor is TlCaBaCuO. In another preferred embodiment, the superconductor comprises TlSrCuO. Processes for making high temperature superconducting system are also disclosed.
Abstract: The invention relates to production of superconductors, more particularly, LnM.sub.2.sup.II M.sub.3.sup.I O.sub.y compounds where y=6-8; Ln=Y, Sc or lanthanide; M.sup.II =Ba, Ca or Sr; M.sup.I =Cu, Cu+Ag or LnM.sub.2.sup.II M.sup.I O.sub.y-x F where x=1-2. It comprises local initiation of an exothermic reaction in a stoichiometric mixutre of source constituents chosen to provide for production of the afore-mentioned compounds. An exothermic mixture of corresponding constituents includes a non-combustible component and a combustible component comprising at least one metal from the group composed of a rare-earth metal of the periodic system chosen from scandium, yttrium and lanthanide, a metal of group II of the periodic system, a metal of group I of the periodic system or hydride of at least one of said metals.
Type:
Grant
Filed:
November 22, 1989
Date of Patent:
November 12, 1991
Assignee:
Institut Strukturnoi Makrokinetiki an SSSR
Inventors:
Alexandr G. Merzhanov, Inna P. Borovinskaya, Mikael D. Nersesian, Andrei G. Peresada