scholarly journals Effect of water/water vapor on microstructure and phase stability of (Y0.25Bi0.75)2O3 solid electrolytes

2003 ◽  
Vol 18 (11) ◽  
pp. 2624-2632 ◽  
Author(s):  
Chaur-Chi Huang ◽  
Kuan-Zong Fung
Keyword(s):  
Electron Microscopy ◽  
Water Vapor ◽  
Rhombohedral Phase ◽  
Stable Phase ◽  
Similar Reaction ◽  
X Ray Diffraction ◽  
Transmission Electron Microscopy Analysis ◽  
Transmission Electron ◽  
Electron Microscopy Analysis ◽  
Humidified Air

Highly conductive cubic (Y0.25Bi0.75)2O3 tends to transform to rhombohedral (Y0.25Bi0.75)2O3 when annealed at 600°C for more than 200 h. Although the rhombohedral phase of (Y0.25Bi0.75)2O3 was known to be the stable phase at temperatures ≤600°C, it was found that the annealed (Y0.25Bi0.75)2O3 was not thermodynamically stable in the water-containing environment. From x-ray diffraction and transmission electron microscopy analysis, it was observed that the annealed (Y0.25Bi0.75)2O3 easily decomposed into monoclinic α-Bi2O3 and yttrium hydroxide at a temperature as low as 50°C. The monoclinic α-Bi2O3 further reacted with CO2 and formed Bi2O2CO3. Consequently, the annealed (Y0.25Bi0.75)2O3 degraded and became flaky powder. Scanning electron microscopy micrographs of water-reacted (Y0.25Bi0.75)2O3 also showed surface swelling and peeling. Such surface deterioration was caused by a large volume increase during the water reaction. Similar reaction was also observed when the annealed (Y0.25Bi0.75)2O3 was exposed in the humidified air at 300°C. As the temperature was raised to 500°C, little reaction was observed between water vapor and (Y0.25Bi0.75)2O3. The better stability of (Y0.25Bi0.75)2O3 at elevated temperature was observed.

Growth and Characterization of C-Axis Oriented YBa2Cu3O7-x/PrBa2Cu3O7-x Bilayers

1999 ◽  
Vol 13 (09n10) ◽  
pp. 1005-1010 ◽  
Author(s):  
C. Beneduce ◽  
F. Bobba ◽  
M. Boffa ◽  
M. C. Cucolo ◽  
A. M. Cucolo ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
X Ray Diffraction ◽  
Transmission Electron Microscopy Analysis ◽  
X Ray ◽  
Resistivity Measurements ◽  
Transmission Electron ◽  
High Oxygen Pressure ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

We report on the preparation and characterization of YBa 2 Cu 3 O 7-x/ PrBa 2 Cu 3 O 7-x bilayers onto (100) SrTiO 3 substrates. The samples have been prepared by sequential dc sputtering processes in high oxygen pressure from stoichiometric targets. The structural characterization of the YBa 2 Cu 3 O 7-x and PrBa 2 Cu 3 O 7-x films and of the bilayers has been performed by means of X-ray diffraction. The Scanning Electron Microscopy analysis has showed that the film surfaces are flat and free of precipitates. A detailed study of the interfaces has been performed by Transmission Electron Microscopy analysis. The electrical resistivity measurements showed for the YBa 2 Cu 3 O 7-x films sharp superconducting transitions at 91.5 K and critical current density of about 106 A/cm 2 at 77 K, while for the PrBa 2 Cu 3 O 7-x films a semiconductor-like behavior has been observed.

X-ray diffraction and transmission electron microscopy analysis of ordering and structure in Al1−xInxAs thin films

2000 ◽  
Vol 15 (1) ◽  
pp. 45-55 ◽  
Author(s):  
R. L. Forrest ◽  
J. Kulik ◽  
T. D. Golding ◽  
S. C. Moss
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Short Range ◽  
X Ray Diffraction ◽  
Transmission Electron Microscopy Analysis ◽  
X Ray ◽  
Transmission Electron ◽  
Short Range Ordering ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

This paper presents an x-ray diffraction and transmission electron microscopy analysis of Al1−xInxAs grown by molecular beam epitaxy. Two samples grown on (001) InP at temperatures of 370 and 400 °C are characterized. The first, which contains a high density of twin lamellae, exhibits triple-period short-range ordering with a rather short correlation range normal to the (111) planes. Within these (individual) planes, the concentration, however, is uniform over a considerably greater distance, leading to a highly anisotropic scattering. This is the first observation of triple-period short-range ordering in a sample that exhibits 2 × 1 surface reconstruction. The second sample exhibits CuPt-type short-range ordering with scattering that is significantly streaked, suggestive of lamellar-shaped ordered domains. Both samples contain high densities of stacking faults leading to additional sharp streaking along symmetry-allowed 〈111〉 directions.

CHARACTERIZATION AND ELECTRICAL PROPERTIES OF ALIGNED CARBON NANOTUBES WITH HIGH ASPECT RATIO

2011 ◽  
Vol 10 (01n02) ◽  
pp. 23-28
Author(s):  
RAVI BHATIA ◽  
V. PRASAD ◽  
M. REGHU
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Aspect Ratio ◽  
Multiwall Carbon Nanotubes ◽  
High Quality ◽  
Transmission Electron Microscopy Analysis ◽  
Transmission Electron ◽  
Electron Microscopy Analysis ◽  
High Degree

High-quality multiwall carbon nanotubes (MWNTs) were produced by a simple one-step technique. The production of MWNTs was based on thermal decomposition of the mixture of a liquid phase organic compound and ferrocene. High degree of alignment was noticed by scanning electron microscopy. The aspect ratio of as-synthesized MWNTs was quite high (more than 4500). Transmission electron microscopy analysis showed the presence of the catalytic iron nanorods at various lengths of MWNTs. Raman spectroscopy was used to know the quality of MWNTs. The ratio of intensity of the G-peak to the D-peak was very high which revealed high quality of MWNTs. Magnetotransport studies were carried out at low temperature and a negative MR was noticed.

scholarly journals Morphological changes and bioaccumulation in response to cadmium exposure in Morchella spongiola, a fungus with potential for detoxification

2021 ◽  
Author(s):  
Hongyan Xu ◽  
Jing Guo ◽  
Qing Meng ◽  
Zhanling Xie
Keyword(s):  
Electron Microscopy ◽  
Morphological Changes ◽  
Intracellular Accumulation ◽  
Tolerance Mechanism ◽  
Edible Fungi ◽  
Transmission Electron Microscopy Analysis ◽  
Transmission Electron ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Micro Morphology

<i>Morchella</i> is a genus of edible fungi with strong resistance to Cd and the ability to accumulate it in the mycelium. However, the mechanisms conferring Cd resistance in <i>Morchella</i> are unknown. In the present study, morphological and physiological responses to Cd were evaluated in the mycelia of <i>Morchella spongiola</i>. Variations in hyphal micro-morphology including twisting, folding and kinking in mycelia exposed to different Cd concentrations (0.15, 0.9, 1.5, 2.4, 5.0 mg/L) were observed using scanning electron microscopy. Deposition of Cd precipitates on cell surfaces (at Cd concentrations > 2.4 mg/L) was shown by SEM-EDS. Transmission electron microscopy analysis of cells exposed to different concentrations of Cd revealed the loss of intracellular structures and the localization of Cd depositions inside/outside the cell. FTIR analysis showed that functional groups such as C=O, -OH, -NH and -CH could be responsible for Cd binding on the cell surface of <i>M. spongiola</i>. In addition, intracellular accumulation was observed in cultures at low Cd concentrations (< 0.9 mg/L), while extracellular adsorption occurred at higher concentrations. These results provide valuable information on the Cd tolerance mechanism in <i>M. spongiola</i> and constitute a robust foundation for further studies on fungal bioremediation strategies.

Sign in / Sign up

Export Citation Format

Share Document