Abstract: A now superconducting material comprising a compound oxide represented by the general formula:(Sr,.gamma.).sub.x (La,.delta.).sub.1-x .epsilon..sub.y Cu.sub.1-y O.sub.3-zin which".gamma." represents an element of IIa group of the periodic table except Sr, an atomic ratio of .gamma. to Sr being selected in a range between 1% and 90%,".delta." represents an element of IIIa group of the periodic except La, an atomic ratio of .delta. to La is selected in a range between 1% and 90%,".epsilon." represents a metal element of Vb 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, and the expression of (Sr,.gamma.) and (La,.delta.) mean that the respective elements position predetermined sites in a crystal in a predetermined proportion.

Abstract: A process of forming on a substrate a coating of a precursor of a crystalline rear earth alkaline earth copper oxide or heavy pnictide mixed alkaline earth copper oxide electrical conductor and converting the precursor to the crystalline electrical conductor.

Abstract: A superconductor consisting of a sufficiently pure phase of the oxides of Bi, Sr, Ca, and Cu to exhibit a resistive zero near 110K resulting from the process of forming a mixture of Bi.sub.2 O.sub.3, SrCO.sub.3, CaCO.sub.3 and CuO into aparticulate compact wherein the atom ratios are Bi.sub.2, Sr.sub.1.2-2.2, Ca.sub.1.8-2.4, Cu.sub.3. Thereafter, heating the particulate compact rapidly in the presence of oxygen to an elevated temperature near the melting point of the oxides to form a sintered compact, and then maintaining the sintered compact at the elevated temperature for a prolonged period of time. The sintered compact is cooled and reground. Thereafter, the reground particulate material is compacted and heated in the presence of oxygen to an elevated temperature near the melting point of the oxide and maintained at the elevated temperature for a time sufficient to provide a sufficiently pure phase to exhibit a resistive zero near 110K.

Abstract: A Bi-Pb-Sr-Ba-Ca-Cu-O system superconductor having a composition of:Bi.sub.l Pb.sub.m Sr.sub.p Ba.sub.q Ca.sub.y Cu.sub.z O.sub.xwherein l, m, p, q, y and z satisfy the following inequalities:0.50<l<1.500.01.ltoreq.m.ltoreq.0.600.70.ltoreq.p.ltoreq.1.600.005.ltoreq.q.ltoreq.0.800.70.ltoreq.y.ltoreq.1.601.40.ltoreq.z.ltoreq.3.00which has the critical temperature of at least 77 K, and contains the high T.sub.c phase in a high fraction.

Abstract: To produce a high-temperature superconductor of the composition Bi.sub.(2+a) (Sr.sub.(1-b) Ca.sub.b).sub.(3-a) Cu.sub.(2+c) O.sub.(8+x), where a is from 0 to 0.3, b is from 0.1 to 0.9 and c is from 0 to 2, and x has a value which depends on the oxidation state of the metals contained, oxides and/or carbonates of bismuth, strontium, calcium and copper are thoroughly mixed. In this process, the copper compound is used as a mixture of copper(I) oxide and copper(II) oxide. Then the mixture of oxides and/or carbonates is first allowed to react mutually in an inert gas atmosphere at temperatures from 700.degree. to 800.degree. C. for 0.5 to 36 hours before subsequently treating the mixture in an oxygen-containing atmosphere at temperatures from 700.degree. to 875.degree. C. for 3 to 60 hours.

Abstract: A method of preparing a high temperature superconductor from an amorphous phase. The method involves preparing a starting material of a composition of Bi.sub.2 Sr.sub.2 Ca.sub.3 Cu.sub.4 Ox or Bi.sub.2 Sr.sub.2 Ca.sub.4 Cu.sub.5 Ox, forming an amorphous phase of the composition and heat treating the amorphous phase for particular time and temperature ranges to achieve a single phase high temperature superconductor.

Abstract: Bulk form of superconducting materials are produced by pouring a melt a O.sub.2 -containing superconducting material into a heated mold, cooling the mold until solidification begins, removing the cast object from the mold, gradually cooling the cast object to prevent the development of thermal stresses, and then annealing the cast, cooled object to restore O.sub.2 to near equilibrium levels. The bulk form produced according to the present invention may be used as a sputtering target in the production of wires, or as a bulk form semiconductor.

Abstract: An oriented superconducting material may be made by cold pressing a nonoriented superconducting material selected from the group consisting of Bi.sub.1, Bi.sub.2, Tl.sub.1, Tl.sub.2, Pb substituted Bi.sub.1, Pb substituted Bi.sub.2, Pb substituted Tl.sub.1, and Pb substituted Tl.sub.2 superconductor materials at a pressure sufficient to form an oriented superconducting material.

Abstract: A process for preparing powder of high temperature oxide superconductors of Bi-Pb-Sr-Ca-Cu-O type. In an aqueous solution of nitrate salts of Bi, Pb, Sr, Ca, and Cu metals, an appropriate ratio of triethylamine/oxalic acid was added to form a coprecipitate. Through the process of calcination at a temperature in the range of 750.degree. C. to 800.degree. C. and sintering at a temperature of 860.degree. C., a uniform and fine powder superconductive metal oxide having a critical temperature of 110K is obtained as the final product.

Abstract: The present invention provides a process for producing a superconducting material capable of elevating the Tc of oxide superconductors, in particular Bi-based superconductors. The feature of the present invention resides in a process for producing an oxide superconductor, in which a intermediate product or a product showing superconducting property is treated with a solution containing a compound having a reducing or oxidizing function. As the compound having a reducing function, compounds having two or more enolic hydroxy groups, cycloaliphatic polyhydric alcohol compounds or inorganic type reducing compounds are preferred. As the compound having oxidizing function, there can be mentioned, for example, carbonyl compounds, ozone, hydrogen peroxide, organic peroxide, dimethylsulfoxide and permanganate.

Abstract: A high-Tc oxide superconductor including Bi, Sr, Ca, Cu, O and at least one of Pb and Al, with a high critical temperature than that of liquid nitrogen. A method for producing the high-Tc oxide superconductor is also disclosed, in which Bi.sub.2 O.sub.3, SrCO.sub.3, CaCO.sub.3, CuO and PbO or Al.sub.2 O.sub.3 powders are mixed, calcined, ground, cold-pressed and sintered. The calcined mixture may be melted and annealed to obtain a tape-form superconductor.

Abstract: The superconducting device according to the present invention is provided with a superconducting thin film of the Bi-Sr-Ca-Cu oxide deposited on a substrate thereof. Consequently, the device can be produced at a low cost because no rare earth elements are required.The superconducting thin film according to the present invention is formed by sputtering onto a substrate from a Bi-Sr-Ca-Cu oxide target, followed by annealing in an oxidizing atmosphere. In this way, it is possible to produce a superconducting thin film of the Bi-Sr-Ca-Cu oxide in a simple way by using an ordinary sputtering apparatus. In this method, it is preferable that a MgO substrate be used and the optimum annealing temperature is about 880.degree. C.

Abstract: Compositions having the nominal formula Bi.sub.2 Sr.sub.3-x Y.sub.x Cu.sub.2 O.sub.8+y wherein x is from about 0.05 to about 0.45 and y is from about 0 to about 1 are superconducting.

Abstract: A superconductor and precursor therefor from oxide mixtures of Ca, Sr, Bi and Cu. Glass precursors quenched to elevated temperatures result in glass free of crystalline precipitates having enhanced mechanical properties. Superconductors are formed from the glass precursors by heating in the presence of oxygen to a temperature below the melting point of the glass.

Abstract: A conductive film of crystalline bismuth mixed alkaline earth oxide containing silver is disclosed. A process for promoting the growth of crystalline bismuth mixed alkaline earth oxide grains by incorporating silver prior to sintering is also disclosed.

Abstract: A fundamental pinning mechanism has been identified in the Bi-Sr-Ca-Cu-O system. The pinning strength has been greatly increased by the introduction of calcium- and copper-rich precipitates into the sample matrix. The calcium and copper are supersaturated in the system by complete melting, and the fine calcium and copper particles precipitated during subsequent crystallization anneal to obtain the superconducting phases. The intragrain critical current density has been increased from the order of 10.sup.5 A/cm.sup.2 to 10.sup.7 A/cm.sup.2 at 5 T.

Abstract: This invention is directed to the formation of homogeneous, aqueous precursor mixtures of at least one substantially soluble metal salt and a substantially soluble, combustible co-reactant compound, typically an amino acid. This produces, upon evaporation, a substantially homogeneous intermediate material having a total solids level which would support combustion. The homogeneous intermediate material essentially comprises highly dispersed or solvated metal constituents and the co-reactant compound. The intermediate material is quite flammable. A metal oxide powder results on ignition of the intermediate product which combusts same to produce the product powder.

Abstract: Disclosed is a process for the preparation of a composite metal oxide superconductor, in which a composite metal oxide composition comprising Bi, Pb, Sr, Ca and Cu and further containing an alkali metal at a specific ratio is used as the starting material, and this composite metal oxide composition is molded and fired. According to this process, precipitation of the 80 K phase and other impurities is controlled, and a superconductor containing a large quantity of the 110 K phase and a high critical temperature is obtained.

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.

Abstract: A mixture comprised of an alkali chloride solvent and reactants comprised of bismuth sesquioxide, calcium oxide, strontium oxide and copper oxide, or precursors therefor, wherein the reactants are formulated to produce a superconducting reaction product, is heated to melt the chloride solvent in which the reactants then dissolve and react precipitating a Bi-Ca-Sr-Cu-O superconductive material which is comminuted to produce a sinterable powder.

Abstract: A process for producing a sinterable doped superconductive powder which contains a sufficient amount of superconductive compound which is at least coated with sufficient uranium-235 and/or plutonium-239 dopant atoms to enable the sinterable powder to be formed into a sintered superconductive body which can be irradiated with thermal neutrons to produce from about 0.25.times.10.sup.14 to about 5.times.10.sup.14 fission events per cubic centimeter of the resulting irradiated superconductive body, said superconductive compound being selected from the group consisting of Bi.sub.2 CaSr.sub.2 Cu.sub.2 O.sub.8 .+-.x where x ranges from zero to 0.5, Bi.sub.2-y Pb.sub.y Ca.sub.2 Sr.sub.2 Cu.sub.3 O.sub.10.+-.z where y ranges from 0.1 to 0.5 and z ranges from zero to less than 1, and mixtures thereof.

Abstract: An oxide superconductive material comprising constituent elements mainly composed of ABiCuO in which A comprises at least one element of alkaline earth metals, and having a C-plane orientation, and a method of orienting such superconductive materials by hot extrusion from a rectangular nozzle.

Abstract: This invention describes the way to prepare high purity Bi-based superconducting powders with the zero resistance temperature at 110K. The technique employs the dissolution of corresponding metal nitrates in deionized water, plus oxalic acid to chelate the metal cations. The amount of oxalic acid equals to about half of the total nitrate anion in molar ratio. After pH adjustment and gelation, optimal calcination results in 110K superconducting powders in high purity.

Abstract: Binary memory storage devices and cryotrons utilizing superconducting crystals exhibiting an onset of superconductivity and a relatively weak flux exclusion at a temperature T1 and the onset of relatively strong flux exclusion at T2, where T1>T2>77K, are controlled by dc magnetic fields. The preferred superconducting crystals have the formula Bi.sub.2 Sr.sub.3-z Ca.sub.z Cu.sub.2 O.sub.8+w wherein z is from about 0.1 to about 0.9 and w is greater than zero but less than about 1.

Abstract: A glass-ceramic superconductor is disclosed, having a nominal stoichiometric composition consisting essentially of the oxides of Bi, Ca, Sr, Cu and Zn in the stoichiometric formula range: Bi.sub.2 Ca.sub.x Sr.sub.z Zn.sub.n Cu.sub.w O.sub.y, wherein x ranges about 1-2, z ranges about 1-2, n ranges about 0.001-2, w ranges about 1-2, and y ranges about 6-11. These compositions exhibit greatly improved glass stability, yet can yield highly crystalline superconductors which may include large platelet crystals and which can exhibit very low room temperature resistivity.

Abstract: A reactant particulate mixture comprised of Bi.sub.2 CaSr.sub.2 Cu.sub.2 O.sub.8.+-.x where x ranges from 0 to 0.5, Ca.sub.2 CuO.sub.3, cupric oxide and lead oxide is formulated and reacted to produce superconductive Bi.sub.2-y Pb.sub.y Ca.sub.2 Sr.sub.2 Cu.sub.3 O.sub.10.+-.z where y ranges from 0.1 to 0.5 and z ranges from zero to less than 1.

Abstract: A particulate mixture comprised of Bi.sub.2 CaSr.sub.2 Cu.sub.2 O.sub.8.+-.x where x ranges from 0 to 0.5, Ca.sub.2 CuO.sub.3, cupric oxide and lead oxide, wherein the Bi.sub.2 CaSr.sub.2 Cu.sub.2 O.sub.8.+-.x crystals are oriented with their c-axis at least sufficiently parallel to each other so as not to differ significantly from a common direction, is initially reacted producing an intermediate swollen partially reacted product which is pressed to remove the swelling and then sintered to produce a superconductive Bi.sub.2 yPb.sub.y Ca.sub.2 Sr.sub.2 Cu.sub.3 O.sub.10.+-.z body where y ranges from 0.1 to 0.5 and z ranges from zero to less than 1.

Abstract: In a process for depositing a superconducting thin film of bismuth-containing compound oxide on a substrate by physical vapor deposition, the improvement wherein the substrate is heated at a temperature between 670.degree. and 750.degree. C. during the deposition.

Abstract: Superconductors of the Bi-Pb-Sr-Ca-Cu-O system and Tl-Pb-Ba-Ca-Cu-O system having a high Tc phase (about 110K and about 125K, respectively, or more) at a high proportion are obtained by adding a calcium compound which forms CaO and a liquid phase at a temperature for firing the superconductors, e.g., Ca.sub.2 PbO.sub.x (x=3 or 4); or by starting form a composition represented by the formula: Bi.sub.2 Pb.sub.(n-1)/2 Sr.sub.2 Ca.sub.n Cu.sub.n+1 O.sub.b, or Tl.sub.2 Pb.sub.(n-1)/2 Ba.sub.2 Ca.sub.n Cu.sub.n+1 Ob where 2.ltoreq.n.ltoreq.10, 5.ltoreq.b.ltoreq.40.5, i.e., at a ratio of Ca:Pb=2:1.

Abstract: The invention relates to an apparatus and method to detect a magnetic field by measuring the magnetically modulated resistance of a superconductor maintained at its phase transition temperature (T.sub.c).

Abstract: A Ca carbonate powder, a Sr carbonate powder, and a Cu oxide powder are mixed in predetermined proportions, and sintered at a first predetermined temperature into a Ca-Sr-Cu--O oxide sintered body. A Bi oxide powder and a Pb oxide powder are mixed in predetermined proportions, and are sintered at a second predetermined temperature into a Bi--Pb--O oxide sintered body. The obtained Ca--Sr--Cu--O oxide sintered body and Bi--Pb--O oxide sintered body are crushed, and the resulting Ca--Sr--Cu--O oxide powder and Bi--Pb--O oxide powder are mixed in predetermined proportions. The resulting mixed powder is sintered at a third predetermined temperature into a Bi--Pb--Sr--Ca--Cu--O superconductive oxide sintered body, which is crushed into a powder of a Bi-based superconductive oxide containing Pb. A sintered body of the Bi-based superconductive oxide containing Pb is formed from the Bi-based superconductive oxide powder.

Abstract: A metal oxide material is provided which is represented by the composition formula:A.sub.2 B.sub.x Cu.sub.y O.sub.zwherein 2.ltoreq.x.ltoreq.3.5, 2.ltoreq.y.ltoreq.3.5, x+y>4, and 4<z; A is an element or a group of elements selected from alkaline earth metal elements; and B is an element or a group of elements selected from the group of elements consisting of bismuth, lead and thallium. The material has a superconductivity transition temperature of from 4.2K to 12K.

Abstract: A superconducting ceramic powder of Bi/Sr/Ca/Cu/O system are formed in a film and the c-axes are uniformly aligned with the normal of the film. The alignment of the axes is accomplished by dripping ethylalcohol containing the ceramic powder into ethyl alcohol contained in a reservoir. The ceramic powder is settled on a substrate arranged in the reservoir in film form. After removing ethylalcohol, the ceramic film is fired.

Abstract: Black crystal compositions having the empirical composition Bi.sub.a Sr.sub.b Cu.sub.c O.sub.d are described where a+b+c=1, A=0.36-0.557, b=0.098-0.496, c=0.1-0.4 and d=approximately 1+a/2. These compositions have a superconducting transition temperature T.sub.c for superconductivity of greater than 20 K and contain a principal phase which crystallizes in the orthorhombic system. They can be prepared from the mixture of the oxides in the atomic ratio stated by heating to 700.degree.-1000.degree. C.

Abstract: A process for producing a superconductor of an oxide system, which comprises uniformly dissolving, dispersing or suspending in a solvent metal elements for constituting the oxide system at least partly in the form of carboxylates with the rest, if any, being in the form of alkoxides, acetylacetonates and/or inorganic compounds, followed by removal of the solvent to obtain a homogeneous mixture, and sintering the mixture.

Abstract: A novel process for preparing superconductor of bismuth-containing compound oxide such as Bi--Sr--Ca--Cu system.In the present invention, firstly an intermediate compound oxide containing metal elements of the superconductor except bismuth is prepared and then the intermediate compound oxide is contacted with bismuth oxide vapour at a temperature between 750.degree. and 950.degree. C. so that bismuth oxide is reacted with said intermediate compound oxide.

Abstract: A new class of Bi-based superconductive oxides is disclosed. As do the previously known Bi-based superconductors, the novel materials have a perovskite-like crystal structure. However, in contradistinction to the prior art materials, the inventive materials have unmixed B-site occupany, with all substituents occupying A-sites. This tends to produce marginal stability and enhanced transition temperatures, as compared to the prior art Bi-based oxide superconductors. Materials according to the invention have composition ABiO.sub.3-.delta., with A being Ba and at least one monovalent element (typically chosen from Na, K,Rb, and Cs) and 0.ltoreq..delta..ltorsim.0.1, and have a transition temperature T.sub.c.sup.onset .gtorsim.13K. The superconductive materials are advantageously produced from precursor material that contains an excess of the monovalent element(s), as compared to the final composition.