Time Resolved Temperature Measurement of Single Gold Structures via Luminescence Thermometry

MRS Advances ◽  
2018 ◽  
Vol 3 (14) ◽  
pp. 747-751 ◽  
Author(s):  
Ali Rafiei Miandashti ◽  
Martin Kordesch ◽  
Hugh H. Richardson

ABSTRACTHere we report the use of luminescence thermometry to measure the temperature decay from single gold structure into the substrate of AlGaN:Er3+ film. We looked at Er3+ ion photoluminescence upon illumination by modulated 532 nm laser and recorded time-resolved luminescence of 2H11/2 → 4I15/2 and the 4S3/2 → 4I15/2 energy transitions. We calculated the heat generated from gold microdisk and observed the rate of heat dissipation to the environment. We directly calculated the absolute thermal conductivity of 1.7 W/mK for AlGaN: Er3+ film which was in agreement with the literature.

2011 ◽  
Vol 10 (01n02) ◽  
pp. 151-154
Author(s):  
S. P. PAL ◽  
P. SEN

Time-resolved fluorescence spectroscopy has been employed to study the ultrafast heat dissipation dynamics of silver nanoparticles dispersed in methanol, tetrahydrofuran, and hexane. The average relaxation time obtained is in the order of several hundreds of picoseconds indicating lack of band-edge emission where lack of scaling of these times with the thermal conductivity of the surrounding medium indicate disparate heat dissipation pathways.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1812
Author(s):  
Qin Gang ◽  
Rong-Tsu Wang ◽  
Jung-Chang Wang

A thermoelectric pipe (TEP) is constructed by tubular graphite electrodes, Teflon material, and stainless-steel tube containing polymeric nanofluids as electrolytes in this study. Heat dissipation and power generation (generating capacity) are both fulfilled with temperature difference via the thermal-electrochemistry and redox reaction effects of polymeric nanofluids. The notion of TEP is to recover the dissipative heat from the heat capacity generated by the relevant machine systems. The thermal conductivity and power density empirical formulas of the novel TEP were derived through the intelligent dimensional analysis with thermoelectric experiments and evaluated at temperatures between 25 and 100 °C and vacuum pressures between 400 and 760 torr. The results revealed that the polymeric nanofluids composed of titanium dioxide (TiO2) nanoparticles with 0.2 wt.% sodium hydroxide (NaOH) of the novel TEP have the best thermoelectric performance among these electrolytes, including TiO2 nanofluid, TiO2 nanofluid with 0.2 wt.% NaOH, deionized water, and seawater. Furthermore, the thermal conductivity and power density of the novel TEP are 203.1 W/(m·K) and 21.16 W/m3, respectively.


2013 ◽  
Vol 48 (4) ◽  
pp. 477-482 ◽  
Author(s):  
David O. Draper ◽  
Amanda R. Hawkes ◽  
A. Wayne Johnson ◽  
Mike T. Diede ◽  
Justin H. Rigby

Context: A new continuous diathermy called ReBound recently has been introduced. Its effectiveness as a heating modality is unknown. Objective: To compare the effects of the ReBound diathermy with an established deep-heating diathermy, the Megapulse II pulsed shortwave diathermy, on tissue temperature in the human triceps surae muscle. Design:  Crossover study. Setting: University research laboratory. Patients or Other Participants: Participants included 12 healthy, college-aged volunteers (4 men, 8 women; age = 22.2 ± 2.25 years, calf subcutaneous fat thickness = 7.2 ± 1.9 mm). Intervention(s):  Each modality treatment was applied to the triceps surae muscle group of each participant for 30 minutes. After 30 minutes, we removed the modality and recorded temperature decay for 20 minutes. Main Outcome Measure(s): We horizontally inserted an implantable thermocouple into the medial triceps surae muscle to measure intramuscular tissue temperature at 3 cm deep. We measured temperature every 5 minutes during the 30-minute treatment and each minute during the 20-minute temperature decay. Results: Tissue temperature at a depth of 3 cm increased more with Megapulse II than with ReBound diathermy over the course of the treatment (F6,66 = 10.78, P < .001). ReBound diathermy did not produce as much intramuscular heating, leading to a slower heat dissipation rate than the Megapulse II (F20,220 = 28.84, P < .001). Conclusions:  During a 30-minute treatment, the Megapulse II was more effective than ReBound diathermy at increasing deep, intramuscular tissue temperature of the triceps surae muscle group.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Manavendra P. Singh ◽  
Manab Mandal ◽  
K. Sethupathi ◽  
M. S. Ramachandra Rao ◽  
Pramoda K. Nayak

AbstractDiscovery of two-dimensional (2D) topological insulators (TIs) demonstrates tremendous potential in the field of thermoelectric since the last decade. Here, we have synthesized 2D TI, Sb2Te3 of various thicknesses in the range 65–400 nm using mechanical exfoliation and studied temperature coefficient in the range 100–300 K using micro-Raman spectroscopy. The temperature dependence of the peak position and line width of phonon modes have been analyzed to determine the temperature coefficient, which is found to be in the order of 10–2 cm−1/K, and it decreases with a decrease in Sb2Te3 thickness. Such low-temperature coefficient would favor to achieve a high figure of merit (ZT) and pave the way to use this material as an excellent candidate for thermoelectric materials. We have estimated the thermal conductivity of Sb2Te3 flake with the thickness of 115 nm supported on 300-nm SiO2/Si substrate which is found to be ~ 10 W/m–K. The slightly higher thermal conductivity value suggests that the supporting substrate significantly affects the heat dissipation of the Sb2Te3 flake.


2018 ◽  
Vol 254 ◽  
pp. 771-777 ◽  
Author(s):  
Daniel Struk ◽  
Amol Shirke ◽  
Alireza Mahdavifar ◽  
Peter J. Hesketh ◽  
Joseph R. Stetter

2000 ◽  
Vol 123 (3) ◽  
pp. 273-277 ◽  
Author(s):  
Robert J. Samuels ◽  
Nancy E. Mathis

The present study examines the relationship between thermal conductivity and planarity in polyimide films. The samples tested were specially prepared to range in orientation from three dimensionally random to highly planar. The molecular structure and orientation of the polyimide film have been characterized by polarizing microscope techniques, while the thermal conductivity measurements were done using a new rapid nondestructive technique. This correlation represents the first time thermal conductivity has been measured by modified hot wire techniques and related to the internal structure of polyimide. This work contributes to a deeper theoretical understanding of thermal conductivity and heat transfer mechanisms as they relate to orientation. Thermal conductivity evaluation could provide a new tool in the arsenal of structural characterization techniques. This relationship between thermal conductivity and orientation is key for applications of directional heat dissipation in the passive layers of chip assemblies. Such a correlation has potential to speed the development cycles of new materials during formulation as well as assure properties during production.


2017 ◽  
Vol 898 ◽  
pp. 1532-1538
Author(s):  
Yue Gao ◽  
Qian Jin Mao ◽  
Hai Wang ◽  
Zi Ming Wang ◽  
Su Ping Cui

Aiming at the heat dissipation of equipment, and based on ANSYS finite element simulation of thermal conductivity of coatings, the heat-dissipation coating filled with graphite and carbon nanotubes respectively, which integrates heat conduction (high thermal conductivity) and radiation (high emissivity), was successfully prepared by the method of solution mixing. Meanwhile, the effects of filler content, type and shape on thermal conductivity and emissivity of the coating were also investigated. The results indicate that the rising tendency between the simulated data by FEM and experimental value is consistent, which has a certain directive significance. In addition, graphite can improve the thermal conductivity and emissivity of the coating effectively; however, the emissivity decreases when the content exceeds 23.08%. The carbon nanotubes can improve the thermal conductivity and emissivity simultaneously, the thermal conductivity is 2.3 times that of pure resin, and the emissivity is up to 0.91 at the 2.0% mass fraction of carbon nanotubes.


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