Low Temperature Preparation of y‐bA‐cU‐0 Films by Omcvd

1989 ◽  
Vol 169 ◽  
Author(s):  
Taiji Tsuruoka ◽  
Ryodo Kawasaki ◽  
Hitoshi Abe ◽  
Susumu Shibata
Keyword(s):  
Low Temperature ◽  
Deposition Rate ◽  
X Ray Diffraction ◽  
Axis Orientation ◽  
X Ray ◽  
Low Temperature Preparation ◽  
Zero Resistance ◽  
Diffraction Patterns ◽  
Temperature Preparation

AbstractBy using N2O for oxygen source, Y‐Ba‐Cu‐O films prepared at 650” C on the SrTiO3 substrates showed zero resistance at 79K. The deposition rate of Y‐Ba‐Cu‐0 films on MgO(l00) substrates by using N2O gas was nearly half of that using 02 gas. X‐ray diffraction patterns of Y‐Ba‐Cu‐0 films grown on SrTiO3(100) and MgO(l00) substrates indicate c‐axis orientation.

Apparent Activation Energy in Low Temperature Aging of Y-TZP Ceramics

2010 ◽  
Vol 105-106 ◽  
pp. 100-103
Author(s):  
Qi Fei Xie ◽  
Cheng Wang ◽  
Qing Feng Zan ◽  
Li Min Dong
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Apparent Activation Energy ◽  
Coordinate Systems ◽  
X Ray Diffraction ◽  
X Ray ◽  
Low Temperature Aging ◽  
Diffraction Patterns ◽  
Straight Lines ◽  
Temperature Aging

Apparent activation energy in low temperature aging of two kinds of Y-TZP ceramic was studied in this paper. The ceramics were processed into small pieces, and aging in 100°C, 110°C, 120°C, 130°C and 140°C respectively. The content of monoclinic phase was calculated by X-ray diffraction patterns and the microstructure was scanned by SEM. According to MAJ law and Arrhenius formation, straight lines were fitted in coordinate systems of ln (ln (1/(1 − f )))-ln t and ln b-1/T, and the kinetic parameters of low temperature aging of Y-TZP ceramic were calculated according to these lines. The results revealed that grain size significantly affected apparent activation energy of Y-TZP ceramics.

scholarly journals Low temperature preparation of α-tricalcium phosphate and its mechanical properties

2017 ◽  
Vol 11 (2) ◽  
pp. 100-105 ◽  
Author(s):  
Song Wang ◽  
Yaping Wang ◽  
Kangning Sun ◽  
Xiaoning Sun
Keyword(s):  
Mechanical Properties ◽  
Flexural Strength ◽  
Tricalcium Phosphate ◽  
Annealing Temperature ◽  
Thermal Transformation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Low Temperature Preparation ◽  
Scanning Electron ◽  
Temperature Preparation

In this work, ?-tricalcium phosphate (?-TCP) was successfully prepared by the thermal transformation of amorphous calcium phosphate (ACP) precursor. ?-cyclodextrin (?-CD) was used for preparation of ACP precursor and played an important role in designing its special structure. The phase composition and microstructures of the obtained ?-TCP at different annealing temperature were analysed by X-ray diffraction and scanning electron microscope, and confirmed that ?-TCP can be prepared at 650?C for 3 h using ACP as precursor, which is much lower than the phase transition temperature of ?-TCP. Mechanical properties were tested 24 h after mixing the obtained ?-TCP with 30 wt.% of deionised water. The compressive strength and the flexural strength were 26.4MPa and 12.0MPa, respectively. The flexural strength was higher than that of ?-TCP prepared by other methods.

Textured Superconducting Thin Films of Bismuth Cuprate by Laser Ablation Method

1989 ◽  
Vol 169 ◽  
Author(s):  
Ashok Kumar ◽  
L. Ganapathi ◽  
J. Narayan
Keyword(s):  
Thin Films ◽  
Laser Ablation ◽  
Bulk Material ◽  
Lattice Parameter ◽  
Superconducting Thin Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Laser Ablation Method ◽  
Zero Resistance ◽  
Diffraction Patterns

AbstractWe have prepared highly textured superconducting thin films from Bi1.5pb0.5Ca3Sr2Cu4Ox (2324) on (100) YS-ZrO2 (Yttria stabilized zirconia) and Bi1.5Pb0.5Ca2Sr2Cu3°x (2223) on LaAlC-3 (100) and MgO (100) substrates at 650°C by pulsed laser ablation method.These films showed 2212 type of phase of the (BiPb)2(Ca,Sr)n+1CunO2n+4+5 family with onset transition temperature ( Tc ) ~ 110 K, confirming our earlier observations of 110 K superconductivity in a n = 2 bulk material. Thin films deposited from 2324 bulk target on YS-Z1O2 showed zero resistance temperature (Tco ) of 68 K but post annealing for one hour at 400°C in oxygen improved Tco from 68 K to 82 K. Thin films from 2223 target on LaAlO3 ( 100 ) and MgO ( 100 ) exhibited a Tco of 65 K and 74 K respectively while onset remained the same at 110 K. Further annealing at 400°C for one hour in oxygen did not show any improvement in Tco. X-ray diffraction (XRD), scanning electron microscopy (SEM) and Rutherford backscattering (RBS) channeling studies were performed on these films for correlation between crystal structure, microstructure and superconducting properties. X-ray diffraction patterns indicated 2212 type phase with a= 5.39 Å and c=30.76 Å; preferential orientation of c-axis perpendicular to the substrate was observed. The lattice parameter and x-ray diffraction patterns were found to be invariant with annealing treatments.

High Tc Superconducting Y-Ba-Cu-O Thick Fim by Screen Printing

1987 ◽  
Vol 99 ◽  
Author(s):  
H. H. Yen ◽  
J. H. Kung ◽  
Y. C. Chen ◽  
P. T. Wu
Keyword(s):  
Film Thickness ◽  
Screen Printing ◽  
Copper Oxides ◽  
Onset Temperature ◽  
Superconducting Film ◽  
X Ray Diffraction ◽  
High Tc ◽  
X Ray ◽  
Zero Resistance ◽  
Diffraction Patterns

ABSTRACTSuperconducting film of ternary copper oxides from the Y-Ba-Cu-O system has been prepared by screen printing on 96% A1203 substrate with onset temperature at 95K and zero resistance at 85K. X-ray diffraction patterns show that film will react with the A1203 substrate. With decreasing film thickness the superconductivity is destroyed and may become a semiconductor.

Synthesis of Metal Sulfide Powders From Organometallics

1986 ◽  
Vol 73 ◽  
Author(s):  
Curtis E. Johnson ◽  
Deborah K. Hickey ◽  
Daniel C. Harris
Keyword(s):  
Metal Sulfide ◽  
Organometallic Complexes ◽  
X Ray Diffraction ◽  
Organometallic Reagents ◽  
X Ray ◽  
Optical Ceramics ◽  
Low Temperature Preparation ◽  
Temperature Electron ◽  
Organozinc Reagents ◽  
Temperature Preparation

ABSTRACTOrganometallic reagents have been examined for the low-temperature preparation of metal sulfide powders which are desired as precursors to optical ceramics. The general approach is typified by the reaction of diethylzinc with hydrogen sulfide in toluene solution at room temperature. Electron microscopy shows that the white ZnS product consists of aggregates of ≤ 0.1 μm particles. The product is further characterized as predominantly cubic zinc sulfide (X-ray diffraction) which contains some residual hydrocarbon. Various organozinc reagents and experimental procedures have been tried in order to optimize the reaction. The reaction has also been extended to organometallic complexes of Al and Mg, and also to a ternary system, ZnAl2 S4

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