Thermal Characterization of Micro/Nanoscale Wires/Tubes Using Pulsed Laser-assisted Thermal Relaxation

2008 ◽  
Vol 1083 ◽  
Author(s):  
Jiaqi Guo ◽  
Xinwei Wang ◽  
David Geohegan ◽  
Gyula Eres ◽  
Cecile Vincent
Keyword(s):  
Thermal Diffusivity ◽  
Thermal Relaxation ◽  
Pulsed Laser ◽  
Reference Value ◽  
Thermal Characterization ◽  
Copper Electrodes ◽  
Nanosecond Pulsed Laser ◽  
Voltage Variation ◽  
The Wire ◽  
High Level

ABSTRACTA novel transient technique is developed to measure the thermal diffusivity of one-dimensional microscale wires. In this technique, the thin wire is suspended over two copper electrodes. Upon fast (nanosecond) pulsed laser irradiation, the wire's temperature will quickly increase to a high level and then decrease gradually. Such temperature decay can be used to determine sample's thermal diffusivity. To probe this temperature evolution, a dc current is fed through the wire to sensor its voltage variation, from which the thermal diffusivity can be extracted. A 25.4-μ;m thin Pt wire is characterized to verify this technique. Sound agreement is obtained between the measured data and reference value. Applying this pulsed laser-assisted thermal relaxation technique, the thermal diffusivity of multi-wall carbon nanotube bundles and microscale carbon fibers is measured. Detailed analysis is conducted to study the effect of the wire embedded in the paste/base on the final measurement result.

Thermal Characterization of Micro/Nanoscale Conductive and Nonconductive Wires by Transient Photo-Electro-Thermal Technique

2008 ◽  
Author(s):  
Tao Wang ◽  
Xinwei Wang ◽  
Jiaqi Guo ◽  
Zhongyang Luo ◽  
Kefa Cen
Keyword(s):  
Thermal Diffusivity ◽  
Laser Beam ◽  
Thermophysical Properties ◽  
Reference Sample ◽  
Reference Value ◽  
Thermal Characterization ◽  
Transient Temperature ◽  
Voltage Variation ◽  
Thermal Sensing ◽  
The Wire

In this work, a transient photon-electro-thermal (TPET) technique based on step laser heating and electrical thermal sensing is developed to characterize the thermophysical properties of one-dimensional micro/nanoscale conductive and nonconductive wires. In this method, the to-be-measured thin wire/tube is suspended over two electrodes and is irradiated with a step CW laser beam. The laser beam induces a transient temperature rise in the wire/tube, which will lead to a transient change of its electrical resistance. A DC current is applied to the sample, and the resulting transient voltage variation over the wire is measured and used to extract the thermophysical properties of the sample. A 25.4-μm thick Pt wire is used as the reference sample to verify this technique. Sound agreement is obtained between the measured thermal diffusivity and the reference value. Applying the TPET technique, the thermal diffusivity of conductive single-wall carbon nanotube (SWCNT) bundles and nonconductive cloth fibers is measured. For nonconductive wires, a thin (∼nm) metallic film is coated on the outside of the wire for electrical thermal sensing. The measured thermal diffusivity for the SWCNT bundle is 2.53×10−5 m2/s, much less than the thermal diffusivity of graphite in the layer direction. For microscale cloth fibers, our experiment shows its thermal diffusivity is at the level of 10−7 m2/s.

scholarly journals THERMAL CHARACTERIZATION OF MULTI-WALL CARBON NANOTUBE BUNDLES BASED ON PULSED LASER-ASSISTED THERMAL RELAXATION

2008 ◽  
Vol 01 (01) ◽  
pp. 71-76 ◽  
Author(s):  
JIAQI GUO ◽  
XINWEI WANG ◽  
DAVID B. GEOHEGAN ◽  
GYULA ERES
Keyword(s):  
Carbon Nanotube ◽  
Thermal Diffusivity ◽  
Thermal Relaxation ◽  
Thermal Characterization ◽  
Nanosecond Laser ◽  
One Dimensional ◽  
Nanotube Bundles ◽  
The Wire ◽  
Multi Wall Carbon Nanotube

A novel transient technique is developed to measure the thermal diffusivity of one-dimensional microscale wires. In this technique, a pulsed nanosecond laser is used to quickly heat the wire. After laser heating, the wire temperature decays slowly. Such temperature decay is sensed and used to determine the thermal diffusivity of the wire. A 25.4 μm thin Pt wire is characterized to verify this technique. The thermal diffusivity of multi-wall carbon nanotube bundles is measured. Based on the measurement result and the inside structure, the thermal diffusivity of individual carbon nanotubes is estimated.

Laser for carbon nanotubes: From the PLD deposition of the catalytic layer to the thermal characterization by nanosecond pulsed laser

2012 ◽  
Author(s):  
Mireille Gaillard ◽  
Eliane Amin-Chalhoub ◽  
Chantal Boulmer-Leborgne ◽  
Agnès Petit ◽  
Éric Millon ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Pulsed Laser ◽  
Thermal Characterization ◽  
Catalytic Layer ◽  
Nanosecond Pulsed Laser

scholarly journals High level activen+doping of strained germanium through co-implantation and nanosecond pulsed laser melting

2018 ◽  
Vol 123 (16) ◽  
pp. 165101 ◽  
Author(s):  
David Pastor ◽  
Hemi H. Gandhi ◽  
Corentin P. Monmeyran ◽  
Austin J. Akey ◽  
Ruggero Milazzo ◽  
...  
Keyword(s):  
Pulsed Laser ◽  
Laser Melting ◽  
Nanosecond Pulsed Laser ◽  
High Level

Development of pulsed laser-assisted thermal relaxation technique for thermal characterization of microscale wires

2008 ◽  
Vol 103 (11) ◽  
pp. 113505 ◽  
Author(s):  
Jiaqi Guo ◽  
Xinwei Wang ◽  
David B. Geohegan ◽  
Gyula Eres ◽  
Cécile Vincent
Keyword(s):  
Thermal Relaxation ◽  
Pulsed Laser ◽  
Thermal Characterization ◽  
Relaxation Technique

Inside process of glass with nanosecond pulsed laser

2008 ◽  
Author(s):  
Takeji Arai ◽  
Noritaka Asano ◽  
Akihiko Minami ◽  
Hideaki Kusano
Keyword(s):  
Pulsed Laser ◽  
Nanosecond Pulsed Laser

DFT Benchmark Study of the O--O Bond Dissociation Energy in Peroxides Validated with High-Level Ab-Initio Calculations

2019 ◽  
Author(s):  
Danilo Carmona ◽  
Pablo Jaque ◽  
Esteban Vöhringer-Martinez
Keyword(s):  
Reference Value ◽  
Basis Set ◽  
Basis Sets ◽  
Mean Deviation ◽  
Bond Dissociation ◽  
Dissociation Energies ◽  
The Mean ◽  
Experimental Values ◽  
High Level ◽  
Almost All

<div><div><div><p>Peroxides play a central role in many chemical and biological pro- cesses such as the Fenton reaction. The relevance of these compounds lies in the low stability of the O–O bond which upon dissociation results in radical species able to initiate various chemical or biological processes. In this work, a set of 64 DFT functional-basis set combinations has been validated in terms of their capability to describe bond dissociation energies (BDE) for the O–O bond in a database of 14 ROOH peroxides for which experimental values ofBDE are available. Moreover, the electronic contributions to the BDE were obtained for four of the peroxides and the anion H2O2− at the CBS limit at CCSD(T) level with Dunning’s basis sets up to triple–ζ quality provid- ing a reference value for the hydrogen peroxide anion as a model. Almost all the functionals considered here yielded mean absolute deviations around 5.0 kcal mol−1. The smallest values were observed for the ωB97 family and the Minnesota M11 functional with a marked basis set dependence. Despite the mean deviation, order relations among BDE experimental values of peroxides were also considered. The ωB97 family was able to reproduce the relations correctly whereas other functionals presented a marked dependence on the chemical nature of the R group. Interestingly, M11 functional did not show a very good agreement with the established order despite its good performance in the mean error. The obtained results support the use of similar validation strategies for proper prediction of BDE or other molecular properties by DF Tmethods in subsequent related studies.</p></div></div></div>

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