Ordered Structure of Titanium Oxide

Nature ◽  
1966 ◽  
Vol 210 (5039) ◽  
pp. 934-936 ◽  
Author(s):  
D. WATANABE ◽  
J. R. CASTLES ◽  
A. JOSTSONS ◽  
A. S. MALIN
Keyword(s):  
Titanium Oxide ◽  
Ordered Structure

Planar defects in ordered (Ga,In)P

1988 ◽  
Vol 46 ◽  
pp. 902-903
Author(s):  
S. McKernan ◽  
C. B. Carter ◽  
D. Bour ◽  
J. R. Shealy
Keyword(s):  
Electron Diffraction ◽  
Vapor Phase ◽  
Growth Direction ◽  
High Density ◽  
Ordered Structure ◽  
Planar Defects ◽  
Diffraction Patterns ◽  
Ternary Semiconductors ◽  
Anion Species ◽  
Metallic Vapor

The growth of ternary III-V semiconductors by organo-metallic vapor phase epitaxy (OMVPE) is widely practiced. It has been generally assumed that the resulting structure is the same as that of the corresponding binary semiconductors, but with the two different cation or anion species randomly distributed on their appropriate sublattice sites. Recently several different ternary semiconductors including AlxGa1-xAs, Gaxln-1-xAs and Gaxln1-xP1-6 have been observed in ordered states. A common feature of these ordered compounds is that they contain a relatively high density of defects. This is evident in electron diffraction patterns from these materials where streaks, which are typically parallel to the growth direction, are associated with the extra reflections arising from the ordering. However, where the (Ga,ln)P epilayer is reasonably well ordered the streaking is extremely faint, and the intensity of the ordered spot at 1/2(111) is much greater than that at 1/2(111). In these cases it is possible to image relatively clearly many of the defects found in the ordered structure.

Characterisation of planar crystal defects in Y2Fe17Cx (0.6 ≤ x ≤ 1.6) magnetic material by High Resolution Electron Microscopy

1990 ◽  
Vol 48 (4) ◽  
pp. 774-775
Author(s):  
W. Coene ◽  
F. Hakkens ◽  
T.H. Jacobs ◽  
K.H.J. Buschow
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Permanent Magnets ◽  
Annealing Treatment ◽  
High Resolution Electron Microscopy ◽  
Crystal Defects ◽  
Ordered Structure ◽  
X Ray ◽  
Planar Crystal ◽  
Resolution Electron

Intermetallic compounds of the type RE2Fe17Cx (RE= rare earth element) are promising candidates for permanent magnets. In case of Y2Fe17Cx, the Curie temperature increases from 325 K for x =0 to 550 K for x = 1.6 . X ray and electron diffraction reveal a carbon - induced structural transformation in Y2Fe17Cx from the hexagonal Th2Ni17 - type (x < 0.6 ) to the rhombohedral Th2Zn17 - type ( x ≥ 0.6). Planar crystal defects introduce local sheets of different magnetic anisotropy as compared with the ordered structure, and therefore may have an important impact on the coercivivity mechanism .High resolution electron microscopy ( HREM ) on a Philips CM30 / Super Twin has been used to characterize planar crystal defects in rhombohedral Y2Fe17Cx ( x ≥ 0.6 ). The basal plane stacking sequences are imaged in the [100] - orientation, showing an ABC or ACB sequence of Y - atoms and Fe2 - dumbbells, for both coaxial twin variants, respectively . Compounds resulting from a 3 - week annealing treatment at high temperature ( Ta = 1000 - 1100°C ) contain a high density of planar defects.

Electron Holographic Nano-Characterization of Gold Catalyst at Interface

2002 ◽  
Vol 727 ◽  
Author(s):  
S. Ichikawa ◽  
T. Akita ◽  
M. Okumura ◽  
M. Haruta ◽  
K. Tanaka
Keyword(s):  
Contact Angle ◽  
Titanium Oxide ◽  
Gold Catalyst ◽  
Three Dimensional ◽  
High Resolution Electron Microscopy ◽  
Electron Holography ◽  
Gold Particles ◽  
Oxide Support ◽  
The Mean ◽  
A Charge

AbstractThe catalytic properties of nanostructured gold catalyst are known to depend on the size of the gold particles and to be activated when the size decreases to a few nanometers. We investigated the size dependence of the three-dimensional nanostructure on the mean inner potential of gold catalysts supported on titanium oxide using electron holography and high-resolution electron microscopy (HREM). The contact angle of the gold particles on the titanium oxide tended to be over 90° for gold particles with a size of over 5 nm, and below 90° for a size of below 2 nm. This decreasing change in the contact angle (morphology) acts to increase the perimeter and hence the area of the interface between the gold and titanium oxide support, which is considered to be an active site for CO oxidation. The mean inner potential of the gold particles also changed as their size decreased. The value of the inner potential of gold, which is approximately 25 V in bulk state, rose to over 40 V when the size of the gold particles was less than 2 nm. This phenomenon indicates the existence of a charge transfer at the interface between gold and titanium oxide. The 3-D structure change and the inner potential change should be attributed to the specific electronic structure at the interface, owing to both the “nano size effect” and the “hetero-interface effect.”

Titanium Oxide Nanoparticles Improve the Chemotherapeutic Action of Erlotinib in Liver Cancer Cells

2020 ◽  
Vol 16 (4) ◽  
pp. 337-343
Author(s):  
Shaimaa E. Abdel-Ghany ◽  
Eman El-Sayed ◽  
Nour Ashraf ◽  
Nada Mokhtar ◽  
Amany Alqosaibi ◽  
...  
Keyword(s):  
Liver Cancer ◽  
Cancer Cells ◽  
Titanium Oxide ◽  
Phase Distribution ◽  
Oxide Nanoparticles ◽  
Titanium Oxide Nanoparticles ◽  
Liver Cancer Cells ◽  
M Phase ◽  
Apoptosis Detection ◽  
Novel Method

Background: Hepatocellular carcinoma is the second leading cause of cancer-related deaths among other types of cancer due to lack of effective treatments and late diagnosis. Nanocarriers represent a novel method to deliver chemotherapeutic drugs, enhancing their bioavailability and stability. Methods: In the present study, we loaded gold nanoparticles (AuNPs) and titanium oxide nanoparticles (TiO2NPs) with ERL to investigate the efficiency of the formed composite in inducing apoptosis in HepG2 liver cancer cells. Cytotoxicity was assessed using MTT assay and cell phase distribution was assessed by flow cytometry along with apoptosis detection. Results: Data obtained indicated the efficiency of the formed composite to significantly induce cell death and arrest cell cycle and G2/M phase. IRF4 was downregulated after treatment with loaded ERL. Conclusion: Our data showed that loading ERL on TiO2NPs was more efficient than AuNPs. However, both nanocarriers were efficient compared with control.

Titanium Oxide Based Photocatalysts: From Research to Applications

2010 ◽  
Vol 1 (2) ◽  
pp. 165-175 ◽  
Author(s):  
Lianzhou Wang ◽  
Gao Qing (Max) Lu
Keyword(s):  
Titanium Oxide
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