Write-Erase Mechanism of Indium-Antimony Optical Disk Medium

1986 ◽  
Vol 74 ◽  
Author(s):  
Y. Goto ◽  
K. Utsumi ◽  
A. Ushioda ◽  
I. Tsugawa ◽  
N. Koshino
Keyword(s):  
Electron Microscopy ◽  
Phase Diagram ◽  
Transmission Electron Microscopy ◽  
Electron Probe ◽  
Crystal Size ◽  
Optical Disk ◽  
Grain Sizes ◽  
Zinc Blende ◽  
Transmission Electron ◽  
The Difference

AbstractWritten and erased bits of the In-Sb phase change type optical disk medium were studied using transmission electron microscopy (TEN) and electron probe microanalysis (EPMA). Both the bits were separated into inner and outer areas and were composed of only rhombohedral Sb crystals and zinc blende In50Sb50 crystals. The difference between the two bits were in crystal size and atomic distribution of the inner area. Models of the writing and erasing processes were derived from these observations and the In-Sb phase diagram. With these models, the thicknesses, grain sizes and optical contrasts of the both bits were consistently explained.

scholarly journals Effect of Aging Time on Crushing Performance of Al-0.5Mg-0.4Si Alloy for Safety Components of Automobile

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 608
Author(s):  
Jinkun Lu ◽  
Haichun Jiang ◽  
Lingying Ye ◽  
Daxiang Sun ◽  
Yong Zhang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Tensile Test ◽  
Aging Time ◽  
Uniform Elongation ◽  
Total Elongation ◽  
Localized Deformation ◽  
Ductility Index ◽  
Transmission Electron ◽  
The Difference

The effect of aging time on the crushing performance of Al-0.5Mg-0.4Si alloy used for safety components of automobile was investigated by tensile test and crush test. Moreover, the microstructure of the alloy was investigated by transmission electron microscopy (TEM). The results show that the localized deformation ductility index, ΔAabs, which is defined as the difference between total elongation and uniform elongation, of Al-0.5Mg-0.4Si alloy is 6.5%, 7.0% and 8.5%, respectively, after being aged at 210 °C for 1, 3 and 6 h, and this tendency is the same as that of the crushing performance. The spacing of grain boundary precipitates (GBPs) from TEM results are found to be 94.9, 193.6 and 408.2 nm after being aged at 210 °C for 1, 3 and 6 h, respectively, and this tendency is same to that of ΔAabs. A mechanism about the relation between the spacing of GBPs and the ductility index ΔAabs has been proposed based on localized deformation around GBPs. With the increase of GBPs spacing, the ΔAabs increases, and the crushing performance is improved.

Influence of doping on crystal growth, structure and optical properties of nanocrystalline CaTiO3: a case study using small-angle neutron scattering

2015 ◽  
Vol 48 (3) ◽  
pp. 836-843 ◽  
Author(s):  
Oindrila Mondal ◽  
Manisha Pal ◽  
Ripandeep Singh ◽  
Debasis Sen ◽  
Subhasish Mazumder ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Crystal Growth ◽  
Small Angle Neutron Scattering ◽  
Ionic Radius ◽  
Ionic Radii ◽  
Growth Structure ◽  
Transmission Electron ◽  
The Difference

The effect of dopant size (ionic radius) on the crystal growth, structure and optical properties of nanocrystalline calcium titanate, CaTiO3(CTO), have been studied using small-angle neutron scattering. X-ray diffraction, along with high-resolution transmission electron microscopy, confirms the growth of pure nanocrystalline CTO. Rietveld analysis reveals that the difference of ionic radii between dopant and host ions induces strain within the lattice, which significantly affects the lattice parameters. The induced strain, due to the difference of ionic radii, causes the shrinkage of the optical band gap, which is manifested by the redshift of the absorbance band. Mesoscopic structural analysis using scattering techniques demonstrates that the ionic radius of the dopant influences the agglomeration behaviour and particle size. A high-resolution transmission electron microscopy study reconfirms the formation of pure highly crystalline CTO nanoparticles.

Ordering in Compound Semiconductors: The Role of Transmission Electron Microscopy

1998 ◽  
Vol 523 ◽  
Author(s):  
D. S. Su ◽  
A. T. Tham ◽  
P. Schubert-Bischoff ◽  
I. Hähnert ◽  
W. Neumann ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Structure Model ◽  
Zinc Blende ◽  
Transmission Electron ◽  
Semiconductor Compounds ◽  
Ternary Semiconductor ◽  
Ternary Semiconductor Compounds ◽  
Long Range Ordering

AbstractIn this paper, the ordering of ternary semiconductor compounds is briefly reviewed by means of a coordination polyhedron model. Long-range ordering of chalcopyrite and CuAu-type structures can be represented as an array of repeating A2B2 tetrahedra. A CuAu-type ordered phase in a chalcopyrite AIBIIICVI2 compound is surrounded by an A3B+ AB3 boundary, whereas a CuPt-type ordered phase in a zinc-blende (A, B)IIICV compound is surrounded mainly by A2B2 type tetrahedra and thus restricted in size. Following the description of the ordered structure model, the detection of the asymmetry in ordering directions in (A, B)IIICV compounds is discussed. Some examples that employ transmission electron microscopy are presented.

Structural transformation of a kaolinite and calcite mixture to gehlenite and anorthite

2003 ◽  
Vol 18 (2) ◽  
pp. 475-481 ◽  
Author(s):  
Karfa Traoré ◽  
Philippe Blanchart
Keyword(s):  
Electron Microscopy ◽  
Phase Diagram ◽  
Transmission Electron Microscopy ◽  
Electron Diffraction ◽  
Low Temperature ◽  
Orientation Relationship ◽  
Interlayer Spacing ◽  
Direct Transition ◽  
Transmission Electron ◽  
Successive Phase

Kaolinite mixed with calcite was sintered at low temperature (1100 °C; 5 °C/min). The successive phase transformations are metakaolinite to gehlenite and then anorthite, although the available phase diagram indicates a direct anorthite recrystallization. Transmission electron microscopy and electron diffraction studies of nanocrystallites revealed that the transformation path is favored by the structural similarities of phases. In particular, the pseudolayers of gehlenite have a major orientation relationship with the initial metakaolinite layers. The gehlenite axis, [001]G, is parallel to the metakaolinite axis, [001]A. This direct transition is favored by the existence of Si tetrahedral units and 4–fold–coordinated Al in both structures. Ca atoms, initially in the interlayer spacing of metakaolinite, remain in the interlayers of gehlenite. During the second transformation step, anorthite recrystallizes from gehlenite with axis [020]A parallel to [210]G. It is proposed that this orientation relationship is favored by the orientation and shape of Ca-atom channels through both structures, along [001]G and [100]A axes.

Preparation and Luminescence Properties of ZnS: Cu/Fe Nanocrystalline

2014 ◽  
Vol 1033-1034 ◽  
pp. 1054-1057
Author(s):  
Xiang Zhang ◽  
Jin Liang Huang ◽  
Li Hua Li
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Thioglycolic Acid ◽  
Luminescent Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zinc Blende ◽  
Transmission Electron ◽  
Fe Nanoparticles

ZnS: Cu/Fe nanocrystals were synthesized by hydrothermal method with thioglycolic acid as a stabilizer. The phases, grain size and luminescent properties of the nanocrystals were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and fluorescence photometer respectively. The results showed that ZnS: Cu/Fe nanoparticles have a particle size about 7nm and possess a cubic zinc blende crystal structure. The luminous intensity of ZnS: Cu/Fe nanocrystals was strongly when they were reacted at 140°C for 12 hours.

TEM Investigation of Microwave Joined Si-SiC/Al/Si-SiC and α-SiC/Al/α-SiC.

1993 ◽  
Vol 314 ◽  
Author(s):  
S. Arunajatesan ◽  
A. H. Carim ◽  
T. Y. Yiin ◽  
V. K. Varadan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Intimate Contact ◽  
Strength Data ◽  
Transmission Electron

AbstractElectron probe microanalysis (EPMA) and transmission electron microscopy (TEM) have been used to examine the SiC/Al interfaces in microwave joined Si-SiC/Al/Si-SiC and α-SiC/Al/α-SiC. Both the SiC/Al interfaces display intimate contact between the ceramic and metal and are free of porosity. EPMA of the α-SiC/Al/α-SiC joints reveals that no Al has diffused into the bulk α-SiC, unlike the reported diffusion of Al in Si-SiC/Al/Si-SiC. The TEM investigations show that while the Si-SiC/Al/Si-SiC interface is reaction-free, the α-SiC/Al/α-SiC joint contains Si at the interface. The TEM findings are correlated to the strength data available on these joints and the possible reasons for the presence of Si in the absence of Al4C3 in the α-SiC/Al/α-SiC joint are discussed.

Microstructure and growth of joins in melt-textured YBa2Cu3O7−δ

2001 ◽  
Vol 16 (8) ◽  
pp. 2298-2305 ◽  
Author(s):  
A. D. Bradley ◽  
W. Lo ◽  
M. Mironova ◽  
N. H. Babu ◽  
D. A. Cardwell ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Liquid Phase ◽  
Grain Boundary ◽  
Electron Probe ◽  
High Quality ◽  
Strongly Coupled ◽  
External Agent ◽  
Transmission Electron

Joining of melt-textured YBa2Cu3O7-δ (Y123) grains has been achieved without use of an external agent. The technique uses barium-cuprate liquid phase released from platelet boundaries to mediate the growth of Y123 at the interface between two grains. The epitaxial nature and high quality of the growth was determined by optical and transmission electron microscopy. The composition of Ba–Cu–O phases found in some parts of the joins was determined by electron probe microanalysis. A clean low-angle join was found to consist of a grain boundary with dislocation networks and facets. Transport critical current measurements on this type of join revealed strongly coupled behavior. The technique shows promise for the joining of melt-textured material for power engineering applications.

Discrete angle rotations of Bi nanoparticles embedded in a Ga matrix

Open Physics ◽  
2010 ◽  
Vol 8 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Avraham Be’er ◽  
Richard Kofman ◽  
Yossi Lereah
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Time Resolved ◽  
Transmission Electron ◽  
The Difference ◽  
First Time ◽  
Microscopy Images ◽  
Bi Nanoparticles

AbstractSpontaneous instabilities of nanoparticles are known to be influenced by the temperature, and strongly depend on the particle size. However, it is not clear what is the role of the surrounding material that is in contact with the particle. Here we report on the difference between spontaneous rotations of Bi nanoparticles embedded in amorphous SiO and those embedded in liquid Ga. The phenomenon was studied quantitatively by time resolved transmission electron microscopy using Fourier Transform analysis of highresolution electron microscopy images. While rotations of Bi nanoparticles embedded in amorphous SiO occur by all angles, the rotations of Bi nanoparticles embedded in liquid Ga occur by discrete angles. Our results point quantitatively, for the first time, to the role and importance of the contacting surrounding surface during the rotation of nanoparticles.

Stability of Nanometer-Size Si Crystals in Amorphous Si Thin Films under Ion Irradiation

1993 ◽  
Vol 311 ◽  
Author(s):  
Chih M. Yang ◽  
Harry A. Atwater
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Crystal Size ◽  
Ion Irradiation ◽  
Shrinkage Rate ◽  
Nanometer Size ◽  
Size Dependent ◽  
Transmission Electron ◽  
Amorphous Si

ABSTRACTIn this paper we discuss the size-dependent shrinkage rate of nanometer-size Si crystals in amorphous Si thin films during ion irradiation. We obtain shrinkage rate of nanometersize crystals at low temperature under ion irradiation by studying the evolution of the crystal size distribution using transmission electron microscopy. Our results indicate that crystals less than 10 nm in diameter decrease in size faster than larger crystals under ion irradiation. In addition, we fit our data to a capillary model for growth of Si crystals in amorphous Si under ion irradiation.

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