Showing papers in "Materials Research Bulletin in 1987"

TL;DR: In this paper, the authors used thermogravimetry, evolved gas analysis (EGA), x-ray powder diffraction and dilatometry to characterize the oxygen stoichiometry in the 93K superconductor, Ba2YCu3Ox (70>x>60).

TL;DR: In this article, chemical vapor deposition (CVD) was applied to polycrystalline plates with a deposition rate of 200 μm/h and the lattice parameters of the CVD-Ti3SiC2 were investigated.

TL;DR: In this article, the binding energies of 1s electrons (ESCA) for B, C and N indicate that each graphite-like sheet is a composite of all three elements.

TL;DR: In this article, the authors show that the non-existence between two extreme compounds of a Na 1+x Ti 2 (PO 4 ) 3 solid solution seems to result from a topotactic demixtion reaction which requires only Na + and e − transfers without skeleton bond breaking and recombination.

TL;DR: In this paper, a series of layered perovskite oxides, AILaNb2O7 (A = Li, Na, K, Rb, Cs, NH4) constituting n = 2 members of the family A A′n−1BnO3n+1, has been prepared.

TL;DR: In this paper, fine powders consisting of aggregated submicron crystallites of Ba(Ti,Zr)O3 in the complete range of Ti/Zr ratios are prepared at 85-130°C by hydrothermal method, starting from TiO2 + ZrO2 · xH2O mixed gel and Ba(OH)2 solution.

TL;DR: The structure of Ba2YCu3O6 has been determined by neutron diffraction powder profile analysis as mentioned in this paper, and the cell is tetragonal P4/mmm with a = 3.8570(1) A and c = 11.8194(3) A.

TL;DR: In this paper, the lattice constants of the new compounds have been determined by powder X-ray diffraction, and the unit cells are tetragonal with a axes that are unchanged with variation of the intercalated amine.

TL;DR: In this article, the results of single crystal determination of the true Nasicon are given, showing that only the Si/P non-stoechiometry mechanism is present in the Nasicon crystal.

TL;DR: In this paper, the effect of the B-site calcium ion on the ferroelectric transition of BaTiO3 ceramics was investigated by X-ray diffraction, TEM, SEM, and by measurements of dielectric properties and equilibrium electric conductivity.

TL;DR: In this paper, superconducting cuprate perovskites with Ba2YCu3O7 incorporating a variety of rare earth ions are reported, and they show high temperature superconductivity in phases containing ions carrying magnetic moments.

TL;DR: In this paper, thin films of V1−xFexO2 (O<-x≤0.12) were prepared by r.f. reactive sputtering, and the resistivity of these films was measured from 25°C to 100°C.

TL;DR: In this paper, the X-ray diffractograms of the powder showed line broadening and a high concentration of lattice defects in these crystallites, and the optical spectra of the particle suspensions in water showed that the absorption around the band gap is considerably broadened, together with the appearance of maxima in the far ultraviolet.

TL;DR: In this article, the superconducting oxides YBa2Cu3O7−x and HoBa2cu3O 7−x degrade in the presence of atmospheric water and then complete breakdown to give a mixture of insulating products.

TL;DR: In this article, a novel family of borates formulated MLnB/sub 9/O/sub 16/ (M = Sr or Ba, Ln = rare earth), is reported.

TL;DR: In this paper, the luminescence of Eu3+ in the borates BaLnB9O16 (Ln = La, Gd and Y) has been investigated.

TL;DR: In this paper, a single phase perovskite Ba(Ti, Sn)O3 was obtained up to 35 atom % Sn. The particle size of the resulting BaSnO3 ranges from 0.2-0.6 μm.

TL;DR: A simple model of oxygen-vacancy ordering in ab planes, uncorrelated along the c axis-unit cell: ∼2√2ac × 2√ 2ac × 3ac, a c ~ 3.80 A −, seems to account for all experimental evidence.

TL;DR: In this article, the effects of thermal hydrogen absorption-desorption cycling on the intrinsic degradation of LaNi5 and LaNi4.7Al0.3 were investigated through the P-C-T curve changes with cycles.

TL;DR: In this article, the Jahn-Teller effect which characterizes nickel (III) in NaNiO2, disappears for x ≥ 0.20 in the NaCoxNi1−xO2 solid solutions.

TL;DR: In this article, the reaction CaC4O4 · 2.5H2OCaC 4O4· 1H2O + 1.5h2O single crystals remain undisturbed and lattice dimensions practically identical both in the water-rich and in the partially dehydrated form.

TL;DR: In this paper, the first order transitions at high temperatures above 600 °C in LiLnS2 (Ln=Dy, Ho, Er, Y), NaNdS2, and NaCeSe2 were investigated.

TL;DR: An expanded version of composite nomenclature is presented, based on the principles of connectivity, property type, tensor rank, size scale, and orientation, which conforms to intuitive ideas of importance but is based on rigorous application of rules of precedence.

TL;DR: In this paper, a method of obtainment of β SiC powders under conditions of the self-propagating high-temperature synthesis (SHS), based on the exothermic reaction between silicon micropowders and active carbon substrates (carbon black and charcoal), has been developed.

TL;DR: In this article, a new structural type Cs2Mo12Se14 containing only Mo12Se 14 cluster units was proposed, which is a metallic conductor with an unusual temperature dependence of its resistivity.

TL;DR: In this paper, single crystals of β-PtO2 have been grown from Pt-KC103-mixtures at 40 kbar, 1500 °C in a modified Belt-type apparatus using Pt-capsules.

TL;DR: In this paper, an almost vertical orientation of the dmp between the phosphate layers is proposed, as was found previously for the unsubstituted phenanthroline analogue, and Spectroscopic evidence for the formation of dimers to the intercalated dmp is described.

TL;DR: In this article, a single crystal of [Y(H 2 O) 3 ] 2 (C 6 Br 2 O 4 ) 3 ·6H2 O and [Y (H 2 OD) 3 ) 2 (c 6 Cl 2 OD 4 ) 2− ions (XCl, Br) was grown in aqueous silicagel.

TL;DR: In this paper, a perovskite-like layer-type phase of K/sub 2/NiF/sub 4/-type was detected for the high T/sub c/ superconductivity of the Ba-La-Cu-O system.

TL;DR: In this article, the importance of hole-hole pairing giving rise to OO bonds is also indicated, and it is shown that hole hole pairing is crucial for superconductivity.