scholarly journals Present studies of thermophysical properties of high-gemperature ceramic superconductors.

Netsu Bussei ◽  
1990 ◽  
Vol 4 (2/3) ◽  
pp. 77-86
Author(s):  
Hitoshi Kawaji ◽  
Tooru Atake
Keyword(s):  
Thermophysical Properties ◽  
Ceramic Superconductors

Study of segregation in La1.8Sr0.2CuO4 superconductor by STEM-EDS microanalysis

1987 ◽  
Vol 45 ◽  
pp. 54-55
Author(s):  
T. F. Kelly ◽  
P. J. Lee ◽  
E. E. Hellstrom ◽  
D. C. Larbalestier
Keyword(s):  
Rare Earth ◽  
High Field ◽  
Transport Current ◽  
Total Thickness ◽  
New Class ◽  
Ceramic Superconductors ◽  
Current Densities ◽  
Group Ii ◽  
Eds Microanalysis

Recently there has been much excitement over a new class of high Tc (>30 K) ceramic superconductors of the form A1-xBxCuO4-x, where A is a rare earth and B is from Group II. Unfortunately these materials have only been able to support small transport current densities 1-10 A/cm2. It is very desirable to increase these values by 2 to 3 orders of magnitude for useful high field applications. The reason for these small transport currents is as yet unknown. Evidence has, however, been presented for superconducting clusters on a 50-100 nm scale and on a 1-3 μm scale. We therefore planned a detailed TEM and STEM microanalysis study in order to see whether any evidence for the clusters could be seen.A La1.8Sr0.2Cu04 pellet was cut into 1 mm thick slices from which 3 mm discs were cut. The discs were subsequently mechanically ground to 100 μm total thickness and dimpled to 20 μm thickness at the center.

Superstructures and ordering phenomena in ceramic superconductors

1996 ◽  
Vol 54 ◽  
pp. 710-711
Author(s):  
R. Gronsky
Keyword(s):  
Domain Growth ◽  
Small Displacement ◽  
Small Scale ◽  
Ceramic Superconductors ◽  
Oxygen Sublattices ◽  
Tweed Contrast ◽  
Diffraction Patterns ◽  
Representative Image ◽  
Static Lattice ◽  
Modulation Wavelength

It is now well established that the phase transformation behavior of YBa2Cu3O6+δ is significantly influenced by matrix strain effects, as evidenced by the formation of accommodation twins, the occurrence of diffuse scattering in diffraction patterns, the appearance of tweed contrast in electron micrographs, and the generation of displacive modulation superstructures, all of which have been successfully modeled via simple Monte Carlo simulations. The model is based upon a static lattice formulation with two types of excitations, one of which is a change in oxygen occupancy, and the other a small displacement of both the copper and oxygen sublattices. Results of these simulations show that a displacive superstructure forms very rapidly in a morphology of finely textured domains, followed by domain growth and a more sharply defined modulation wavelength, ultimately evolving into a strong <110> tweed with 5 nm to 7 nm period. What is new about these findings is the revelation that both the small-scale deformation superstructures and coarser tweed morphologies can result from displacive modulations in ordered YBa2Cu3O6+δ and need not be restricted to domain coarsening of the disordered phase. Figures 1 and 2 show a representative image and diffraction pattern for fully-ordered (δ = 1) YBa2Cu3O6+δ associated with a long-period <110> modulation.

DEVELOPMENT OF POLYMER COMPOSITES WITH IMPROVED THERMOPHYSICAL PROPERTIES FOR SHIPBUILDING AND SHIP REPAIR

2019 ◽  
Vol 10 (2) ◽  
pp. 117-134 ◽  
Author(s):  
A. V. Akimov ◽  
A. V. Buketov ◽  
А. А. Sapronov ◽  
Mykola V. Brailo ◽  
S. V. Yakushchenko ◽  
...  
Keyword(s):  
Polymer Composites ◽  
Thermophysical Properties ◽  
Ship Repair

IDENTIFICATION OF THE THERMOPHYSICAL PROPERTIES OF SEMI-TRANSPARENT MATERIALS

Equipment ◽  
2006 ◽  
Author(s):  
O. Wellele ◽  
H. R. B. Orlande ◽  
Nerbe J. Ruperti, Jr. ◽  
Marcelo J. Colaco ◽  
A. Delmas
Keyword(s):  
Thermophysical Properties ◽  
Transparent Materials
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