Optical Properties and New Functionality of Nanocrystalline CuCl and Ge

1992 ◽  
Vol 283 ◽  
Author(s):  
Yasuaki Masumoto
Keyword(s):  
Optical Transition ◽  
Optical Gain ◽  
Glassy Matrix ◽  
Bulk Crystals ◽  
Electron Microscopic ◽  
Visible Photoluminescence ◽  
Resolution Electron ◽  
Microscopic Studies ◽  
Direct Optical Transition ◽  
First Time

ABSTRACTLasing of nanocrystalline CuCl embedded in a NaCl single crystal wasobserved for the first time. Lasing takes place at 77 K in nanocrystalline CuCl sandwiched between dielectric mirrors under the pulsed ultraviolet laser excitation. The lasing transition is that from bi-exciton to exciton. The lasing is observed up to 108 K. The optical gain of nanocrystalline CuCl is almost the same as that of bulk crystals in spite of the low concentration of CuCl in the NaCl matrix.The origin of visible photoluminescence of nanocrystalline Ge in SiO2 glassy matrix has been studied. Spectroscopic analyses of nanocrystalline Ge indicate that the room-temperature photoluminescence comes from nanocrystalline Ge of diameter of 4 nm or less. High-resolution electron microscopic studies imply that the structure of nanocrystalline Ge of diameter ≤ 4 nm differs from the diamond structure. These data suggest that new nanostructure crystalline Ge having a character of direct optical transition exhibits the visible photoluminescence.

A microscopic marker experiment study on high temperature oxidation of Ni-Al alloy

1986 ◽  
Vol 44 ◽  
pp. 514-515
Author(s):  
Shou-kong Fan
Keyword(s):  
Transport Mechanism ◽  
High Temperature Oxidation ◽  
Transverse Section ◽  
Al Alloy ◽  
Metal Interface ◽  
Electron Microscopic ◽  
Temperature Oxidation ◽  
Analytical Electron ◽  
Microscopic Studies ◽  
First Time

Transmission and analytical electron microscopic studies of scale microstructures and microscopic marker experiments have been carried out in order to determine the transport mechanism in the oxidation of Ni-Al alloy. According to the classical theory, the oxidation of nickel takes place by transport of Ni cations across the scale forming new oxide at the scale/gas interface. Any markers deposited on the Ni surface are expected to remain at the scale/metal interface after oxidation. This investigation using TEM transverse section techniques and deposited microscopic markers shows a different result,which indicates that a considerable amount of oxygen was transported inward. This is the first time that such fine-scale markers have been coupled with high resolution characterization instruments such as TEM/STEM to provide detailed information about evolution of oxide scale microstructure.

High resolution electron microscopic studies of Ni-9.3 and 14.7 at.%Ti alloys

1986 ◽  
Vol 34 (7) ◽  
pp. 1401-1408 ◽  
Author(s):  
H. Yoshida ◽  
M. Arita ◽  
A. Cerri ◽  
G. Kostorz
Keyword(s):  
High Resolution ◽  
Electron Microscopic ◽  
Ti Alloys ◽  
Resolution Electron ◽  
Microscopic Studies

High-Resolution Electron Microscopic Studies of CS Structure in Reduced WO3Thin Crystals

1983 ◽  
Vol 22 (Part 1, No. 5) ◽  
pp. 863-868 ◽  
Author(s):  
Toshio Miyano ◽  
Masazumi Iwanishi ◽  
Chihiro Kaito ◽  
Makoto Shiojiri
Keyword(s):  
High Resolution ◽  
Electron Microscopic ◽  
Resolution Electron ◽  
Microscopic Studies

Electron microscopic studies of internal gettering of nickel in silicon

1990 ◽  
Vol 5 (5) ◽  
pp. 1013-1016 ◽  
Author(s):  
P.K. Sinha ◽  
W.S. Glaunsinger
Keyword(s):  
Electron Microscopy ◽  
Front Surface ◽  
High Resolution Electron Microscopy ◽  
Nickel Silicide ◽  
Back Surface ◽  
Electron Microscopic ◽  
Resolution Electron ◽  
Microscopic Studies ◽  
Argon Ions ◽  
Electron Microdiffraction

The internal gettering of nickel in (100) silicon wafers implanted with 2.5 ⊠ 1015 argon-ions/cm2 at 280 keV has been studied by electron microscopy. Nickel deposited on the back surface is gettered by forming a discontinuous layer of nickel silicide, NiSi2, in the argon-implanted region near the front surface. Electron microdiffraction and high-resolution electron microscopy indicate that the layers of nickel silicide probably grow epitaxially on the undamaged silicon surrounding the silicide.

MoS2 Microtubes: An Electron Microscopy Study

1998 ◽  
Vol 05 (01) ◽  
pp. 423-426 ◽  
Author(s):  
M. Remškar ◽  
Z. Škraba ◽  
F. Cléton ◽  
R. Sanjinés ◽  
F. Lévy
Keyword(s):  
Gas Flow ◽  
Stacking Faults ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Electron Microscopic ◽  
Resolution Electron ◽  
Scanning Electron Microscopic ◽  
Microscopic Studies ◽  
Turbulent Gas Flow ◽  
Scanning Electron

Recently it was found that instability of thin weakly bonded MoS 2 sheets against folding can lead to a growth of hollowed microtubes with several mm lengths, 1–20 μm diameter and less than 0.1 μm wall thickness.1 Bent sheets can directly roll up into the tube or they can produce in their microfolds a turbulent gas flow of transported molecules which promotes a tubelike growth mode. These uncommon stable features of inorganic crystals reveal a great similarity to much smaller carbon fullerences and especially to inorganic ( MoS 2, WS 2) nested fullereness-nanotubes.2 Scanning electron microscopic studies of cylindrical microtubes and twisted microribbons are combined with high resolution electron microscopic observations of stacking faults.

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