Critical current density and ultra high-voltage transmission electron microscopic image for melt-processed fine filamentary EuBa2Cu3Ox superconductors

2004 ◽  
Vol 415 (3) ◽  
pp. 103-108 ◽  
Author(s):  
T. Goto ◽  
K. Watanabe ◽  
E. Ban ◽  
Y. Matsui ◽  
T. Nagai ◽  
...  
RSC Advances ◽  
2016 ◽  
Vol 6 (48) ◽  
pp. 42334-42346 ◽  
Author(s):  
Suchitra Parija ◽  
Arup R. Bhattacharyya

Transmission electron microscopic image of separated MWCNTs (N51L15G5) showing the wrapped polymer chains on the MWCNTs surface, which corresponds to the α-phase of the PP.


1993 ◽  
Vol 07 (06n07) ◽  
pp. 1387-1413 ◽  
Author(s):  
H.-U. NISSEN ◽  
C. BEELI

A review is presented of high-resolution transmission electron microscopic studies on icosahedral, decagonal and dodecagonal quasicrystals executed during the last eight years, especially at ETH Zürich, with special consideration of the use made of tilings for the interpretation of the electron microscopic image contrast. Since the contrast contains information on the projected potential of the quasicrystal structure, the local details of decorated and undecorated tilings can be correlated to the image contrast. These tilings can even be superimposed directly onto the micrographs as an aid in structural interpretation. Also, tilings can directly be constructed by computer on the basis of contrast maxima or minima appearing in the image. These tilings serve to differentiate between quasiperiodic tiling and random tiling quasicrystal structures. Examples of the successful application of these types of tilings in the structural interpretation of electron microscopic observations on quasicrystal alloys are presented.


2008 ◽  
Vol 23 (12) ◽  
pp. 3363-3369 ◽  
Author(s):  
C.V. Varanasi ◽  
J. Burke ◽  
L. Brunke ◽  
H. Wang ◽  
J.H. Lee ◽  
...  

Previous work on YBa2Cu3O7−x (YBCO) + BaSnO3 (BSO) films with a single composition showed significant critical current density (Jc) improvements at higher fields but lowered Jc in low fields. A detailed study on BSO concentrations provided here demonstrates that significant Jc enhancement can occur even up to 20 mol% BSO inclusion, where typical particulate inclusions in these concentrations degrade the YBCO performance. YBCO + BSO films were processed on (100) LaAlO3 substrates using premixed targets of YBa2Cu3O7-x (YBCO) with additions of 2, 4, 10, and 20 mol% BSO. The critical transition temperature Tc of the films remained high (>87 K), even with large amounts (20 mol%) of BSO. YBCO + BSO films showed a gradual increase in Jc at high fields as the amount of BSO was increased. More than an order of magnitude increase in Jc was measured in YBCO + BSO samples as compared to regular YBCO at 4 T. YBCO + 10 mol% BSO films showed overall improvement at all the field ranges while YBCO + 20 mol% BSO was better only at high fields. Transmission electron microscopy revealed the presence of ∼7–8-nm-diameter BSO nanocolumns, the density of which increased with increasing BSO content correlating well with the observed improvements in Jc.


2004 ◽  
Vol 12 (1) ◽  
pp. 3-7
Author(s):  
Stephen W. Carmichael ◽  
Jon Charlesworth

The use of fluorescent probes is becoming more and more common in cell biology. It would be useful if we were able to correlate a fluorescent structure with an electron microscopic image. The ability to definitively identify a fluorescent organelle would be very valuable. Recently, Ying Ren, Michael Kruhlak, and David Bazett-Jones devised a clever technique to correlate a structure visualized in the light microscope, even a fluorescing cell, with transmission electron microscopy (TEM).Two keys to the technique of Ren et al are the use of grids (as used in the TEM) with widely spaced grid bars and the use of Quetol as the embedding resin. The grids allow for cells to be identified between the grid bars, and in turn the bars are used to keep the cell of interest in register throughout the processing for TEM. Quetol resin was used for embedding because of its low auto fluorescence and sectioning properties. The resin also becomes soft and can be cut and easily peeled from glass coverslips when heated to 70°C.


2000 ◽  
Vol 15 (2) ◽  
pp. 285-295 ◽  
Author(s):  
T. G. Holesinger ◽  
J. F. Bingert ◽  
M. Teplitsky ◽  
Q. Li ◽  
R. Parrella ◽  
...  

A detailed compositional analysis of high-critical-current-density (Jc) (55 and 65 kA/cm2at 77 K) (Bi,Pb)2Sr2Ca2Cu3Oy(Bi-2223) tapes was undertaken by energy dispersive spectroscopy in the transmission electron microscope. Structural features were coupled with characteristic compositions of the Bi-2223 phase. The average of all compositional measurements of the Bi-2223 phase was determined to be Bi1.88Pb0.23Sr1.96Ca1.95Cu2.98Oy. However, spatial variations in the Bi-2223 composition and differing phase equilibria were found throughout the filament structure. In particular, a considerable range of Bi-2223 compositions can be found within a single tape, and the lead content of the Bi-2223 phase is significantly depressed in the vicinity of lead-rich phases. The depletion of lead in the Bi-2223 phase around the 3221 phases may be a current-limiting microstructure in these tapes.


1989 ◽  
Vol 169 ◽  
Author(s):  
A. Mogro-Campero ◽  
L.G. Turner ◽  
E.L. Hall ◽  
N. Lewis

AbstractThin films of nominal composition YBa2Cu3O7‐x (YBCO) were produced on (100) SrTiO3 substrates by coevaporation and furnace annealing. Film thicknesses in the range of 0.2 to 2.4/μm were analyzed. Microstructural investigations by cross sectional transmission electron microscopy (TEM) reveal a continuous layer of about 0.4 μm thickness adjacent to the substrate with c‐axis normal to the substrate plane. In thicker films the remaining top portion has the c‐axis in the film plane. The critical current density (J ) at 77 K decreases with increasing thickness in the thickness range exceeding 0.4 μm, qualitatively consistent with the microstructural observations, but quantitatively inconsistent with a simple model based on the microstructural data.


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