scholarly journals High‐Purity Er 3 N@C 80 Films: Morphology, Spectroscopic Characterization, and Thermal Stability

2021 ◽  
pp. 2000546
Author(s):  
Jürgen Weippert ◽  
Seyithan Ulaş ◽  
Patrick Per Meyer ◽  
Dmitry V. Strelnikov ◽  
Artur Böttcher
Keyword(s):  
Thermal Stability ◽  
High Purity ◽  
Spectroscopic Characterization

Thermal Stability of Ni40Ti40Nb20 and Ni32Ti48Nb20 Tapes Obtained by Rapid Solidification Technique

2012 ◽  
Vol 188 ◽  
pp. 41-45
Author(s):  
György Thalmaier ◽  
Ioan Vida-Simiti ◽  
N. Jumate ◽  
Viorel Aurel Şerban ◽  
C. Codrean ◽  
...  
Keyword(s):  
Thermal Stability ◽  
High Purity ◽  
Elevated Temperatures ◽  
Graphite Crucible ◽  
Argon Atmosphere ◽  
Membrane Reactors ◽  
Master Alloys ◽  
Selective Membrane ◽  
Dta Analysis ◽  
Thermal Stability Of

Nickel–titanium- group 5A metal (V, Nb, Ta, Zr) alloys are known as promising hydrogen-selective membrane materials. They can potentially be used in membrane reactors, which can produce high-purity H2 and CO2 streams from coal-derived syngas at elevated temperatures. The master alloys were prepared by arc melting using high purity metals in a Ti-gettered argon atmosphere. The alloys were melted several times in order to improve homogeneity. The ingots were induction-melted under a high-purity argon atmosphere in a quartz tube and graphite crucible injected through a nozzle onto a Cu wheel to produce rapidly solidified amorphous ribbons. Thermal stability of the Ni40Ti40Nb20 and Ni32Ti48Nb20 thin tapes has been examined using DTA analysis.

Comprehensive spectroscopic characterization of high purity metallicity-sorted single-walled carbon nanotubes

2015 ◽  
Vol 252 (11) ◽  
pp. 2512-2518 ◽  
Author(s):  
Marianna V. Kharlamova ◽  
Christian Kramberger ◽  
Markus Sauer ◽  
Kazuhiro Yanagi ◽  
Thomas Pichler
Keyword(s):  
Carbon Nanotubes ◽  
High Purity ◽  
Single Walled Carbon Nanotubes ◽  
Spectroscopic Characterization ◽  
Single Walled Carbon ◽  
Walled Carbon Nanotubes

Thermal Stability and Heat Transfer Characteristics of Methane and Natural Gas Fuels

1994 ◽  
Author(s):  
Douglas Chin ◽  
James C. Hermanson ◽  
Louis J. Spadaccini
Keyword(s):  
Heat Transfer ◽  
Thermal Stability ◽  
Natural Gas ◽  
High Purity ◽  
Operating Conditions ◽  
Stainless Steel Tube ◽  
Heat Transfer Characteristics ◽  
Hydrocarbon Mixtures ◽  
Transfer Characteristics ◽  
Gas Fuel

The thermal decomposition and heat transfer characteristics of gaseous, high-purity methane, several methane-hydrocarbon mixtures and a typical natural gas fuel were evaluated using an electrically heated, stainless-steel tube test apparatus. Of several candidate heat transfer correlations, the Dittus-Boelter heat transfer correlation provided the best fit of the methane heat transfer data over the range of Reynolds numbers 10,000 to 215,000. The thermal stability (i.e. deposit formation) characteristics of the methane-hydrocarbon mixtures and the natural gas fuel were established and compared with the deposition characteristics of high-purity methane. Testing was conducted at wall temperatures up to 900 K (fuel temperatures to 835 K) for durations of up to 60 hours. Measurements of deposit mass indicated that there was essentially no deposit buildup for wall temperatures below 650 K. Deposit began to form at wall temperatures between 650 K and 775 K. Above 775 K, there was a rapid monotonic increase in deposition. The data suggest that the use of high-purity methane instead of natural gas at temperatures above 775 K could reduce the deposit thickness under similar operating conditions by as much as a factor of three, or permit operation at higher temperatures.

Thermal Stability of Deep-Level Defects in High-Purity Semi-Insulating 4H-SiC Substrate Studied by Admittance Spectroscopy

2016 ◽  
Vol 858 ◽  
pp. 357-360
Author(s):  
Naoya Iwamoto ◽  
Alexander Azarov ◽  
Takeshi Ohshima ◽  
Anne Marie M. Moe ◽  
Bengt Gunnar Svensson
Keyword(s):  
Thermal Stability ◽  
High Purity ◽  
Deep Level ◽  
Decisive Role ◽  
Treatment Temperature ◽  
Admittance Spectroscopy ◽  
Chemical Analyses ◽  
Deep Level Defect ◽  
P Type ◽  
Thermal Stability Of

Effects of high temperature treatments on the deep-level defects in high-purity semi-insulating substrates are studied by employing electrical and chemical analyses. Thermal admittance spectroscopy reveals the presence of a deep-level defect, labeled XMID, with a state near the middle of the bandgap, playing a decisive role to realize the semi-insulating characteristics. The concentration of the XMID level decreases with increasing treatment temperature from 1400 to 1700 °C, and consequently, the substrate becomes more conductive toward p-type due to residual boron impurities. The identity of XMID is yet to be known but the carbon vacancy is briefly discussed as a possible candidate.

Synthesis, spectroscopic characterization, thermal stability and compatibility properties of energetic PVB-g-GAP copolymers

2015 ◽  
Vol 22 (9) ◽  
Author(s):  
Xiaofang Wang ◽  
Bo Jin ◽  
Rufang Peng ◽  
Qingchun Zhang ◽  
Wenlin Gong ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Spectroscopic Characterization

Spectroscopic Characterization of Ion-Implanted GaN

2002 ◽  
Vol 743 ◽  
Author(s):  
L. Chen ◽  
B. J. Skromme
Keyword(s):  
Low Temperature ◽  
High Purity ◽  
Spectroscopic Characterization ◽  
Acceptor Pair ◽  
Donor Acceptor ◽  
Optical Activation ◽  
Donor Acceptor Pair ◽  
Low Temperature Photoluminescence ◽  
Do So

ABSTRACTWe investigate implantation of high purity HVPE GaN with Mg, Be, C, Zn, Cd, Ca, N, O, P, As, Ne, and Ar. After annealing at 1300 °C, the material is characterized using low temperature photoluminescence (PL). The Mg acceptors exhibit much better optical activation than Be, C, Zn, Cd, or Ca acceptors implanted and annealed under the same conditions. Acceptor-bound exciton peaks and well-resolved donor-acceptor pair bands are observed for both Mg and Zn. A broad peak centered near 2.78 eV is obtained for Cd, confirming that it is deeper than Zn. Isoelectronic As or P exhibit sharp no-phonon bound exciton lines at 2.952 and 3.200 eV, respectively. Defect-related bands centered at 2.2 and 2.35 eV are studied. Both Be and C strongly enhance the yellow (2.2 eV) PL band, but no other impurities do so, including O.

Thermal Stability and Heat Transfer Characteristics of Methane and Natural Gas Fuels

1995 ◽  
Vol 117 (3) ◽  
pp. 462-467 ◽  
Author(s):  
D. Chin ◽  
J. C. Hermanson ◽  
L. J. Spadaccini
Keyword(s):  
Heat Transfer ◽  
Thermal Stability ◽  
Natural Gas ◽  
High Purity ◽  
Operating Conditions ◽  
Stainless Steel Tube ◽  
Heat Transfer Characteristics ◽  
Hydrocarbon Mixtures ◽  
Transfer Characteristics ◽  
Gas Fuel

The thermal decomposition and heat transfer characteristics of gaseous, high-purity methane, several methane–hydrocarbon mixtures, and a typical natural gas fuel were evaluated using an electrically heated, stainless-steel tube test apparatus. Of several candidate heat transfer correlations, the Dittus–Boelter heat transfer correlation provided the best fit of the methane heat transfer data over the range of Reynolds numbers 10,000 to 215,000. The thermal stability (i.e., deposit formation) characteristics of the methane–hydrocarbon mixtures and the natural gas fuel were established and compared with the deposition characteristics of high-purity methane. Testing was conducted at wall temperatures up to 900 K (fuel temperatures to 835 K) for durations of up to 60 hours. Measurements of deposit mass indicated that there was essentially no deposit buildup for wall temperatures below 650 K. Deposit began to form at wall temperatures between 650 K and 775 K. Above 775 K, there was a rapid monotonic increase in deposition. The data suggest that the use of high-purity methane instead of natural gas at temperatures above 775 K could reduce the deposit thickness under similar operating conditions by as much as a factor of three, or permit operation at correspondingly higher temperatures.

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