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The analysis of the electrical transport properties of the [Bi.sub.2][Sr.sub.2][CaCu,sub,2][O.sub.8X]/AgMg wires show that the application of a magnetic field can really enhance the texture of these tapes. The results show that the change in the texture induces electrical properties that vary with magnetic field orientation.

A study is conducted to examine the influence of the static magnetic field on crystallization of triacylglycerols (TAGs). The conclusion states that symmetrical type TAG's are more sensitive to static magnetic field rather than asymmetrical type of TAGs.

Investigating the crystal growth of the YBCO films by TFA-MOD method is discussed. The crystal growth process of the YBCO in the crystallization atmosphere in detail, the samples prepared by abrupt heating and cooling annealing method.

A project to develop a high-temperature superconducting split magnet for silicon single-crystal growth applications was begun in 1997. Test results for a full-scale magnet are reported.

A method for producing single-domained Y123 crystals via top-seeded melt growth using two step undercooling has been developed. The technique resulted in a large reduction in the amount of time needed to grow the Y123 single-domained crystal. The two step undercooling process, whose resulting Y123 crystals were subjected to analyses of both microstructure and texture, also exhibited no degradation in the superconducting characteristics of the fabricated superconductors.

A wide variety of YBa2Cu3O6+x grain boundaries were created using seeding techniques to control the orientation of grains. In addition, a method to produce grain boundaries in the same sample that have the misorientations theta(001) tilt, theta(100) tilt and 90 degrees-theta(100) where the misorientation angle theta is fully controllable was developed, aside from the five existing domain samples with 90 degrees (100) twist and tilt grain boundaries.

Microbridges were patterned from YSr2Cu2.75Mo0.25O7-delta thin films that were epitaxially grown by pulsed laser ablation. An analysis was then conducted on the superconducting and normal state transport properties of the microbridges. Electrical biases were applied at near room temperature to cause long range displacement of chain oxygen vacancies for examining dopant oxygen mobility.

(YBa2Cu3O7-/Nd0.67Sr0.33MnO3-y)n superlattices were developed using the high-pressure direct current sputtering technique. X-ray analyses reveal that the LaAlO3 (100) substrates exhibit c-axis epitaxial growth. Lattice parameter discrepancies between the substrate and YBa2Cu3O7 sublayers strained the Nd0.67SrO.33MnO3-y films which exhibited ferromagnetic order less than 200 K.

A study was conducted on the influence of Co doping on the intrinsic anisotropic properties of in-plane aligned a-axis YBa2Cu3-xCoxO7-delta thin films grown on (100) LaSrGaO4 substrates using pulsed laser deposition. The quality of Co incorporation was examined using x-ray absorption fine structure analysis and resistivity data. Films with improved Co dopant incorporation but with smaller grain sizes were produced using higher deposition pressures.

A study was conducted on the growth Hg0.9Re0.1Ba2Ca2Cu3O8+x samples on metallic substrates of Ag, AgHg, Au and Pt. The samples were fabricated by combining precursor powders in a dry methanol solution which was then centrifuge coated or pipette-dropped on metal substrates. X-ray diffraction, x-ray microanalysis and scanning electron microscopy were used for the microstructural analysis of grain alignment and phase formation at the superconductor/metal interface.

A novel two-step technique was employed in synthesizing (Hg,Re)Ba2Ca2Cu3Oy (HRBCCO) superconductors with lower annealing temperatures. High phase purity HRBCCO superconductors were fabricated from Ba2Cacu2Ox precursors HgO and Re2O7 in the first step. The second step involves the mixture of finely ground HRBCCO with Ca-Cu-O and HgO. The method succeeded in preparing superconductors with a critical temperature of 133 K.

Melt growth techniques have been successfully used to grow extremely high quality Tl0.5Pb0.5Sr1.6Ba0.4Ca2Cu3Ox epitaxial films as large as 15 micrometers thick on single crystal LaAlO3 substrates. Such films, however, were found to be incompatible with the textured buffer layer yttria-stabilized zirconia. Studies reveal that buffer layer properties required for the epitaxial growth of such films involve texture, chemical stability and lattice matching.

The sample heating rate in Hg-vapor annealing process was modified to permit the analysis of superconducting Hg-based cuprate thin films' growth mechanisms. The growth high-quality c-axis oriented epitaxial HgBa2CaCu2O6+delta films with zero resistance up to 124 K was enhanced using the fast temperature ramping Hg-vapor annealing method. The method also assisted the growth of HgBa2Ca2Cu3O8+delta films with zero resistance up to 130 K.

A study was conducted on the chemical reactions among magnetic flux containing Hg, Ba, Ca, Cu, O and crucibles consisting of Al2O3, Y2O3 and BaZrO3. Previous studies on oxide superconductors containing mercury were utilized in developing the first approach of p-T-x conditions of synthesis. The approach led to the fabrication of large flat single crystals up to 2 x 2 mm2.

A study was conducted on the effects of seed crystallography on the growth and nucleation of single- and multiple-domain large diameter YBa2Cu3Ox levitators. Results show that anisotropic solidification controls the growth of levitators. Several types of seeds were utilized to develop a dual-speed melt textured growth process for the fabrication of bulk crystals that may be used for studying grain boundary transport characteristics.

A bilayer deposition technique was utilized in developing a series of composite films made of Au with YBa2Cu3O7-delta on different substrates. The patterning method was developed to analyze the films' potential for flux flow applications. The technique, however, damaged the composites and an oxygen plasma treatment approach had to be used to restore resistance ratios and critical current density.

A thermal co-evaporation system was used for continuous YBa2Cu3O7-delta film deposition on large areas. Individual metal fluxes were measured through an atomic absorption spectroscopy-based optical rate control system. Results reveal that in situ reloading of metal resources at long time is possible. The grown films also exhibited excellent superconducting properties as compared to films developed using a standard co-evaporation system.

Pulsed laser deposition and ion-beam assisted laser deposition (IBALD) were employed in growing biaxially oriented yttria-stabilized zirconia buffer layers on amorphous substrates at room temperature. IBALD-grown films exhibited up to 20-degrees full-width at half maximum in-plane orientations. High-energy electron diffraction was used for the in-situ monitoring of film growth orientation.

The liquid phase epitaxy approach was employed in growing c-axis oriented Nd1+xCu3Oy thick films on MgO (100) single crystal substrates in Ar gas atmosphere with O.5 at% O2. The superconducting transition temperature became sharp when the film thickness was increased to 100 micrometers. Post-annealing at 300-degrees celsius for 336 hrs was also found to increase the superconducting transition temperature up to 92 K.

A study was conducted on the growth conditions of a cylindrically textured YBCO film on a cylindrically curved surface of single crystalline YSZ. Oxygen ion milling and CeO2 buffer layer deposition were used for the pretreatment of the substrate surface. XRD 2 theta-scan and phi-scan revealed that the a- and b-axes were aligned and that the c-axis was normal to the surfaces.

An off axis deposition geometry is proposed for the enhancement of pulsed laser deposited YBCO thin films' surface quality. Resulting films exhibited excellent superconducting and structural properties as well as a surface morphology free from particulates such as droplets. A 0.12-degree full-width half maximum ofthe rocking curve of (005) YBCO peak was also observed. The effects of deposition parameters on film quality were also analyzed.

The influence of oxygen exposure and substrate temperature during crystal growth on the critical current density and resistivity of Nb/AlOx/Nb Josephson tunnel junctions is investigated at low- and high-exposure regimes. Results show that oxygen exposure affects the junctions' electric properties at the low exposure regime. For high exposure, the tunnel junctions' electric properties are strongly dependent on the substrate temperature.

Differential thermal analysis and optical microscopic techniques were employed to study the crystallization and growth mechanisms during seeded-melt texturing of large-domain YBa2Cu3Ox (123) samples. Specifically, it was found that a large temperature gap exists between partial melting of the 123 material during heating and recrystallization. According to observations, the latter occurs at a temperature below the equilibrium peritectic point.

The influence of platinum additions on the microstructural development of YBa2Cu3O(7-x) thick films grown on magnesium oxide substrates was investigated. Specifically, well textured thick films of YBa2Cu3O(7-x) were produced by adding platinum powder to YBa2Cu3O(7-x) suspensions in an applied magnetic field and partial melt texturing. The process yielded films with enhanced superconducting, magnetic and microstructural properties.

A two-zone thallination furnace was employed to grow smooth TlBa2CaCu2O7 thin films on LaAlO3 substrates from oxide precursors. The experiment, which achieved control of the thallium oxide vapor pressure, yielded TlBa2CaCu2O7 films with high phase purity, a transition temperature of approximately 87 K and a critical current density of 2,000 kA/cm2 at low field and 40 K. In addition, it demonstrated the feasibility of preparing high-quality TlBa2CaCu2O7 thin films at temperatures near 825 degrees Celsius.

The crystal orientations and surface morphology of thin films of YBa2Cu3O(7-x) (YBCO) on YBCO single crystal substrates were investigated. The films, which were grown via off-axis magnetron sputtering, exhibited an axis orientation that was dependent on the growth temperature and lattice mismatches at the interface. The latter was caused by the deoxidation and oxidation of the YBCO substrate during film growth.

Several sets of superconducting thick films are quenched from various stages of the high-temperature thallination process to study their nucleation, growth and colony microstructure. Electron microscopy, x-ray diffraction and electron backscatter diffraction are used in analyzing the films' crystallization properties. Results show that the formation of colonies occur at the onset of 1223 crystallization. This crystallization process occurs in an aligned manner.

The fabrication and characterization of Ba(1-x)KxBiO3 (BKBO) single crystals exhibiting a Meissner state in 70% of its volume fraction has been carried out. The blue-black crystals, which demonstrate a sharp diamagnetic transition at 30 K, were grown on a platinum anode via electrolytic deposition. Besides this, polycrystalline samples with a Meissner effect of about 50% were also powder synthesized at 715 degrees Celsius using a ceramic technology.