Showing papers in "Materials Letters in 1989"

TL;DR: In this article, the dielectric and pyroelectric properties in the solid solution (1 −x) Pb (Mg 1 3 Nb 1 3 ) O 3 : xPbTiO 3 across the morphotropic phase boundary compositions, x = 0.275 − 0.4, are studied as a function of temperature.

TL;DR: In this article, phase-pure orthorhombic YBa 2 Cu 3 O x was obtained by keeping the ratio of O 2 to evolved CO 2 above 50 to ensure phase purity.

TL;DR: In this article, the addition of silver oxide has been found to accelerate the decomposition and melting of the Y-Ba-Cu-O superconductor, which exhibits, after sintering near 980°C, morphology of very large stacked-plate grains for the YBa 2 Cu 3 O 7−δ phase and the presence of decomposition products.

TL;DR: In this article, the dielectric properties of yttria-stabilized cubic zirconia were measured over a wide range of frequency (100 to 1 × 10 10 Hz) and temperature (25 to 200°C).

TL;DR: In this paper, an oxygen-free, stable Fe-rich phase A2, formed peritectically in the range 750-800°C, was found in binary Fe-Nd alloys.

TL;DR: In this paper, the structure of thermally evaporated lead phthalocyanine thin films has been studied as a function of substrate temperature and post-evaporation annealing.

TL;DR: In this paper, an alkoxide sol-gel chemistry has been developed to form superconducting Y 1 Ba 2 Cu 3 O 7−x thin films and bulk powders using two different solvent systems: toluene and methoxyethanol/methylethylketone.

TL;DR: In this paper, high-resolution electron microscopy studies on oxygen-deficient YBa2Cu3O7−δ samples of composition δ = 0.45 and 0.37 having a Tc of 60 K were performed.

TL;DR: The Raman spectra as discussed by the authors are similar to the spectra of glasses prepared by high-temperature melt and vapor deposition techniques, with the addition of a polarized band at 1106 cm−1 and a depolarized band at 933 cm− 1 which varied in intensity with titanium concentration.

TL;DR: In this paper, mixed compounds of transition metal dichalcogenides with a general formula Mo 1− x W x Se 2 (0⩽ x ⩽ 1) have been grown by the direct vapour transport technique and analyzed for absorption properties in the near infrared region.

TL;DR: In this paper, a mathematical method which makes it possible to calculate the kinetic parameters of crystallization, activation energy, E, reaction order, n, and frequency factor, K 0, was developed.

TL;DR: In this article, it was shown that phase separation results only when Nd 3+ concentrations exceed 7 wt% and phase separation can be achieved only when nd 3 + concentrations exceed 15 wt%.

TL;DR: In this paper, it was shown that the flame composition/substrate temperature locus is constrained within a range, a finding which has been confirmed experimentally, and that diamonds may be directly grown on various substrates from an oxy-acetylene flame.

TL;DR: In this article, the electrochemical behavior of diamond films (> 10 μm ) grown on molybdenum using large area, filament assisted chemical vapor deposition (FACVD) was studied in deaerated 0.1 M NaCl solutions.

TL;DR: The mixed oxide NbVO 5 has been synthesized for the first time following a procedure based on sol-gel methods in this paper, where the authors compare these results with various attempts to obtain this compound by other procedures, which appear to be unsuccessful.

TL;DR: In this paper, a microwave dielectric resonator with low loss and temperature stable frequency at about 4 GHz was obtained by adjusting the Nd Sm ratio in ceramics sintered from BaNd 2(1− x Sm 2 x Ti 5 O 14 solid solutions.

TL;DR: In this paper, the ternary compounds UFe 10 Si 2, U 2 Fe 13 Si 4 and U2 Fe 15 Ge 2 have been prepared. The former crystallizes in the tetragonal ThMn 12 -type structure, while the last two have structures which derive from the hexagonal Th 2 Ni 17 -type.

TL;DR: In this article, the high-T c superconducting oxide in the Bi-Sr-Ca-Cu-O system, with a transition temperature at about 80 K, has been fabricated by the sol-gel method using oxalic acid and nitrates as starting materials.

TL;DR: In this article, the primary phase observed by X-ray diffractometry and transmission electron microscopy (TEM) is 1-2-3, where the Ag is contained in discrete grains dispersed uniformly throughout the powder.

TL;DR: Tyranno is a non-crystalline Si-Ti-C-O fiber with carbon and oxygen dispersed within mixed local tetrahedral units as mentioned in this paper, which has been studied using magic angle spinning nuclear magnetic resonance spectroscopy and electron-optical methods.

TL;DR: In this paper, an aerosol process has been used to generate fine YBa 2 Cu 3 O 7−δ superconducting powders by oxidizing a mixture of the three metal nitrates.

TL;DR: In this article, potential-time and linear polarisation data for commercial metallic coatings on steel strip in 1 N NaCl solution have been determined to investigate the connection between the coating corrosion rate and the difference in potential of the coating and steel.

TL;DR: In this article, three superconducting phases, 2 0-2-1, 2 1/2-2 and 2 2 2/2/3, were crystallized sequentially in specific heat-treatment regimes.

TL;DR: In this article, a sintered target of Ni0.6Mn2.4O4 has been used to deposit films with electrical properties identical to bulk Ni 0.6mn2O4.

TL;DR: In this article, the exaggerated grain growth during sintering of superconducting ceramics was investigated, due to the local presence of a small amount of liquid at 1000°C, a few grains of abnormally large size were present in the microstructure.

TL;DR: In this article, isolated porosity was formed in a glass ceramic substrate body by the volatilization of polymer spheres prior to sintering, and the dielectric constant and loss were measured over a frequency range of 200 Hz to 9.3 GHz, at room temperature.

TL;DR: In this article, potential-time and linear polarisation tests together with SEM microanalysis have been used to investigate the corrosion of 55 Al-Zn, Zn and Al hot-dipped coatings on steel in 1 N NaCl solution of pH 4 at 30 °C.

TL;DR: In this article, a new phase has been isolated in the glass forming region and its production and composition is discussed together with initial investigations of the structure of the new phase and its initial structure.

TL;DR: In this paper, the maximum dielectric constant (K = 6812) in the Ba1−xSrxTiO3 (BSTO-29) system was found.

TL;DR: In this article, the authors measured velocities in fresnoite single crystal along several directions and observed that an elastic anomaly occurs near 160°C and that the anomalies may be attributed to a commensurate-incommensurate phase transition.