Abstract: A novel process of the production and processing of high quality, high Tc (Bi,Pb)SCCO superconductors starts with fabrication of a precursor article including selected intermediate phases with desired chemical and structural properties. The precursor fabrication includes mixing raw powders with a desired ratio of Bi:Pb:Sr:Ca:Cu elements and reacting the mixture under different selected reaction conditions that form a precursor powder with a dominant (Bi, Pb)SCCO 2212 phase and without Ca—Pb—O phase, wherein the 2212 phase may be the orthorhombic 2212 phase. The precursor article is then subjected to optimized reaction and mechanical deformation processes that lead to a reaction induced texturing and deformation induced texturing, respectively. A heating process is used to convert the precursor powder to the 2223 phase and subsequent deformation and annealing processes may be used to form a substantially single phase, highly textured (Bi, Pb)SCCO 2223 superconductor with high Jc.

Abstract: A novel process of the production and processing of high quality, high Tc BSCCO or (Bi,Pb)SCCO superconductors starts with fabrication of a forming a bundle including a plurality of billets, each billet containing at least one filament comprising a dominant amount of an tetragonal BSCCO phase with selected intermediate phases, and substantially surrounded by a constraining metal. The bundle is thermomechanically consolidated to form a multifilamentary precursor article by applying pressure and heat to the bundle under conditions cooperatively selected to cause interdiffusion of said constraining metal at the interfaces between said metal and said filaments and substantially complete elimination of voids in said bundle, and the consolidation step is completed before any high strain longitudinal deformation is performed on the bundle.

Abstract: Superconductor reactors, methods and systems are disclosed.

Abstract: The invention relates to multi-layer articles and methods of making such articles. The multi-layer superconductors can have one or more layers with an oriented termination plane. The methods include first conditioning the termination plane of an underlying layer, such as a buffer layer or a superconductor layer, then disposing a layer of material on the conditioned termination plane. The conditioned termination plane can be a high quality termination plane. Superconductor articles formed by these methods can exhibit relatively high critical current densities.

Abstract: Processes for the fabrication of MgB2 powder and wires are provided. Powders are produced by mechanically alloying magnesium- and boron-containing precursors under controlled conditions to avoid secondary phase and impurity formation. Powders are also prepared by vapor phase reaction of volatile magnesium- and boron-containing precursors. Wires, tapes, films and coatings are provided.

Abstract: Oxide bronze compositions and articles manufactured in accordance therewith are provided. The oxide bronze compositions have the general formula AxBOy, in which A comprises an alkali, alkaline earth or rare earth metal and in which A has a valence, m, equal to 1, 2 or 3, B comprises a transition metal having a valence, n, less than or equal to 6,0<x<1 on an atomic ratio basis and y=[(x)(m)+n]/2. High temperature superconducting devices incorporating such compositions are also provided. The superconducting devices include a substrate having a polycrystalline superconducting layer or filament deposited on top of or embedded in the substrate. The superconducting layer or filament is formed of the oxide bronze composition. In some embodiments, the oxide bronze layer is textured with a full-width-half-maximum of a pole figure of less than or equal to 20 degrees.

Abstract: A novel process of the production and processing of high quality, high Tc (Bi,Pb)SCCO superconductors starts with fabrication of a precursor article including selected intermediate phases with desired chemical and structural properties. The precursor fabrication includes introducing the reacted mixture having a dominant amount of the tetragonal BSCCO phase into a metal sheath, and sealing the reacted mixture within said sheath, heating the mixture at a second selected processing temperature in an inert atmosphere with a second selected oxygen partial pressure for a second selected time period, the second processing temperature and the second oxygen partial pressure being cooperatively selected to form a dominant amount of an orthorhombic BSCCO phase in the reacted mixture.

Abstract: The invention relates to multi-layer articles and methods of making such articles. The multi-layer superconductors can have one or more layers with an oriented termination plane. The methods include first conditioning the termination plane of an underlying layer, such as a buffer layer or a superconductor layer, then disposing a layer of material on the conditioned termination plane. The conditioned termination plane can be a high quality termination plane. Superconductor articles formed by these methods can exhibit relatively high critical current densities.

Abstract: Superconductor precursor solutions are disclosed. The precursor solutions contain, for example, a salt of a rare earth metal, a salt of an alkaline earth metal and a salt of a transition metal. The precursor solutions can optionally include a Lewis base. The precursor solutions can be processed relatively quickly to provide a relatively thick and good quality intermediate of a rare earth metal-alkaline earth metal-transition metal oxide.

Abstract: A novel process of the production and processing of high quality, high Tc (Bi,Pb)SCCO superconductors starts with fabrication of a precursor article including selected intermediate phases with desired chemical and structural properties. The precursor fabrication includes mixing raw powders with a desired ratio of Bi:Pb:Sr:Ca:Cu elements and reacting the mixture under different selected reaction conditions that form a precursor powder with a dominant (Bi, Pb)SCCO 2212 phase and without Ca—Pb—O phase, wherein the 2212 phase may be the orthorhombic 2212 phase. The precursor article is then subjected to optimized reaction and mechanical deformation processes that lead to a reaction induced texturing and deformation induced texturing, respectively. A heating process is used to convert the precursor powder to the 2223 phase and subsequent deformation and annealing processes may be used to form a substantially single phase, highly textured (Bi, Pb)SCCO 2223 superconductor with high Jc.

Abstract: An aspected multifilamentary oxide article is provided having a plurality of aspected filaments including a metal oxide and extending continuously for the length of the article. A constraining member substantially surrounds each filament, wherein each of the filaments has an average transverse cross-sectional thickness less than about 35 &mgr;m and an average variation in cross-section along its length of less than about 10%. The article exhibits superior filament uniformity, hardness, and oxide density and texture.

Abstract: A novel process of the production and processing of high quality, high Tc (Bi,Pb)SCCO superconductors starts with fabrication of a precursor article including selected intermediate phases with desired chemical and structural properties. The precursor fabrication includes introducing the reacted mixture having a dominant amount of the tetragonal BSCCO phase into a metal sheath, and sealing the reacted mixture within said sheath, heating the mixture at a second selected processing temperature in an inert atmosphere with a second selected oxygen partial pressure for a second selected time period, the second processing temperature and the second oxygen partial pressure being cooperatively selected to form a dominant amount of an orthorhombic BSCCO phase in the reacted mixture.

Abstract: A multicomponent powder useful in the formation of BSCCO-2223 is provided comprised of orthorhombic BSCCO-2212 and alkaline earth cuprate, without formation of undesirable secondary phases such as alkaline earth bismuthates and alkaline earth plumbates. A method for the production of the multicomponent powder includes providing a mixture of raw materials comprising constituent metallic elements in a ratio corresponding to a superconducting BSCCO-2223 material and heating the mixture under conditions which form a dominant amount of the orthorhombic BSCCO phase and the alkaline earth cuprate phase while preventing formation of an undesirable secondary phase selected from the group of alkaline earth plumbates and alkaline earth bismuthates. A subsequent heating step converts the multicomponent powder into the BSCCO-2223 and subsequent deformation and annealing processes may be used to form a substantially single phase, highly textured (Bi,Pb)SCCO-2223 superconductor article.

Abstract: A method is described to prepare a highly textured oxide superconductor article in a single deformation-sinter process. A precursor article including a plurality of filaments comprising a precursor oxide having a dominant amount of a tetragonal BSCCO 2212 phase and a constraining member substantially surrounding each of the filaments is provided. Each of the filaments extends along the length of the article. The oxide article is subjected to a heat treatment at an oxygen partial pressure and temperature selected to convert a tetragonal BSCCO 2212 oxide into an orthorhombic BSCCO 2212 oxide and, thereafter, roll worked in a high reduction draft in a range of about 40% to 95% in thickness so that the filaments have a constraining dimension is substantially equivalent to a longest dimension of the oxide superconductor grains. The rolled article is sintered to obtain a BSCCO 2223 oxide superconductor.

Abstract: A novel process of the production and processing of high quality, high T.sub.c BSCCO or (Bi,Pb)SCCO superconductors starts with fabrication of a forming a bundle including a plurality of billets, each billet containing at least one filament comprising a dominant amount of an tetragonal BSCCO phase with selected intermediate phases, and substantially surrounded by a constraining metal. The bundle is thermomechanically consolidated to form a multifilamentary precursor article by applying pressure and heat to the bundle under conditions cooperatively selected to cause interdiffusion of said constraining metal at the interfaces between said metal and said filaments and substantially complete elimination of voids in said bundle, and the consolidation step is completed before any high strain longitudinal deformation is performed on the bundle.

Abstract: A novel process of the production and processing of high quality, high T.sub.c (Bi,Pb)SCCO superconductors starts with fabrication of a precursor article including selected intermediate phases with desired chemical and structural properties. The precursor fabrication includes introducing the reacted mixture having a dominant amount of the tetragonal BSCCO phase into a metal sheath, and sealing the reacted mixture within said sheath, heating the mixture at a second selected processing temperature in an inert atmosphere with a second selected oxygen partial pressure for a second selected time period, the second processing temperature and the second oxygen partial pressure being cooperatively selected to form a dominant amount of an orthorhombic BSCCO phase in the reacted mixture.

Abstract: A substrate and apparatus for qualitatively and quantitatively detecting constituents of an environment by surface enhanced Raman spectroscopy. The substrate is composed of two separate phases: an adsorbing phase which has an affinity for the molecular constituents of interest, and a metallic phase that possesses the specific geometry, chemical and electromagnetic properties required to enhance emission of Raman signal frequencies of adsorbed molecules. An apparatus is provided which includes a monochromatic light source, a means to transmit the desired wavelength from the light source to the surface substrate surface, a means to collect the scattered Raman signal frequencies and transmit them to a detector, and a means to analyze the recorded response.

Abstract: A method for measuring the amount of an electroactive gas in a gaseous mixture using an electrochemical cell, the cell including a working electrode (anode), counter electrode (cathode), an electrolyte in which oxygen reduction is inhibited, means for applying a variable potential across the electrodes, and means for measuring current flow between the electrode, the method involving contacting the gaseous mixture with the anode, applying a potential across the anode and cathode and cycling the applied potential between a potential level at which the gas in the gaseous mixture adsorbs onto the anode and a potential level at which the adsorbed gas in the gaseous mixture is oxidized, and measuring the current resulting from the anodic sweep portion of the potential cycle as a measure of the amount of the adsorbed gas in the gaseous mixture.

Abstract: A method for measuring the amount of an electroactive gas in a gaseous mixture using an electrochemical cell, the cell including a working electrode (anode), counter electrode (cathode), an electrolyte in which oxygen reduction is inhibited, means for applying a variable potential across the electrodes, and means for measuring current flow between the electrode, the method involving contacting the gaseous mixture with the anode, applying a potential across the anode and cathode and cycling the applied potential between a potential level at which the gaseous mixture adsorbs onto the anode and a potential level at which the adsorbed mixture is oxidized, and measuring the current resulting from the anodic sweep portion of the potential cycle as a measure of the amount of the adsorbed gas in the gaseous mixture.

Abstract: An electrochemical cell having a housing containing a sodium anode assembly, a cathode assembly, and an electrolyte, in which the electrolyte is a sodium ion conducting alkali metal aluminum tetrahalide and the cathode material is a transition metal chalcogenide, or a reaction product of the chalcogenide and the electrolyte, disposed on a substrate in contact with the electrolyte.