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1. A high temperature instrument for consecutive measurements of thermal conductivity, electrical conductivity, and Seebeck coefficient

   https://doi.org/10.1115/1.4043572  

   Yazdani, Sajad; Kim, Hyun-Young; Pettes, Michael T (January 2019, Journal of Heat Transfer)

   A device for measuring a plurality of material properties is designed to include accurate sensors configured to consecutively obtain thermal conductivity, electrical conductivity, and Seebeck coefficient of a single sample while maintaining a vacuum or inert gas environment. Four major design factors are identified as sample-heat spreader mismatch, radiation losses, parasitic losses, and sample surface temperature variance. The design is analyzed using finite element methods for high temperature ranges up to 1000°C as well as ultra-high temperatures up to 2500°C. A temperature uncertainty of 0.46% was estimated for a sample with cold and hot sides at 905.1 and 908.5°C, respectively. The uncertainty at 1000°C was calculated to be 0.7% for a ?T of 5°C between the hot and cold sides. The thermal conductivity uncertainty was calculated to be -8.6% at ~900°C for a case with radiative gains, and +8.2% at ~1000°C for a case with radiative losses, indicating the sensitivity of the measurement to the temperature of the thermal guard in relation to the heat spreader and sample temperature. Lower limits of -17 and -13% error in thermal conductivity measurements were estimated at the ultra-high temperature of ~2500°C for a single-stage and double-stage radiation shield, respectively. It is noted that this design is not limited to electro-thermal characterization and will enable measurement of ionic conductivity and surface temperatures of energy materials under realistic operating conditions in extreme temperature environments. 

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2. Electrical resistivity, thermal conductivity, and viscosity of Fe-H alloys at Earth's core conditions

   https://doi.org/10.1103/PhysRevB.111.094101  

   Liu, Cong; Cohen, R E (March 2025, Physical Review B)
3. Thermal Conductivity of CaSrFe0.75Co0.75Mn0.5O6-δ

   https://doi.org/10.54963/neea.v3i1.222  

   Medicine_Cloud, Gillian; Guinn, Mandy; Krishna_Hona, Ram (January 2024, New Energy Exploitation and Application)

   CaSrFe0.75Co0.75Mn0.5O6-δ, an oxygen-deficient perovskite, had been reported for its better electrocatalytic properties of oxygen evolution reaction. It is essential to investigate different properties such as the thermal conductivity of such efficient functional materials. The thermal conductivity of CaSrFe0.75Co0.75Mn0.5O6-δ is a critical parameter for understanding its thermal transport properties and potential applications in energy conversion and electronic devices. In this study, the authors present an investigation of the thermal conductivity of CaSrFe0.75Co0.75Mn0.5O6-δ at room temperature for its thermal insulation property study. Experimental measurement was conducted using a state-of-the-art thermal characterization technique, Thermtest thermal conductivity meter. The thermal conductivity of CaSrFe0.75Co0.75Mn0.5O6-δ was found to be 0.724 W/m/K at 25 °C, exhibiting a notable thermal insulation property i.e., low thermal conductivity. 

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4. Thermal Conductivity of CaSrFe2O6-δ

   https://doi.org/10.19080/AJOP.2024.06.555685  

   Hona, Ram Krishna (January 2024, Academic Journal of Polymer Science)

   unknown (Ed.)

   The thermal conductivity of CaSrFe2O6-δ, an oxygen-deficient perovskite, is a critical parameter for understanding its thermal transport properties and potential applications in energy conversion and electronic devices. In this study, we present an investigation of the thermal conductivity of CaSrFe2O6-δ at room temperature for its thermal insulation property study. Experimental measurement was conducted using a state-of-the-art thermal characterization technique, Thermtest thermal conductivity meter. The thermal conductivity of CaSrFe2O6-δ was found to be 0.574W/m/K, exhibiting a notable thermal insulation property. 

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5. Electrical conductivity of metasomatized lithology in subcontinental lithosphere

   https://doi.org/10.2138/am-2021-7942  

   Peng, Ye; Manthilake, Geeth; Mookherjee, Mainak (March 2022, American Mineralogist)

   Abstract A plausible origin of the seismically observed mid-lithospheric discontinuity (MLD) in the subcontinental lithosphere is mantle metasomatism. The metasomatized mantle is likely to stabilize hydrous phases such as amphiboles. The existing electrical conductivity data on amphiboles vary significantly. The electrical conductivity of hornblendite is much higher than that of tremolite. Thus, if hornblendite truly represents the amphibole varieties in MLD regions, then it is likely that amphibole will cause high electrical conductivity anomalies at MLD depths. However, this is inconsistent with the magnetotelluric observations across MLD depths. Hence, to better understand this discrepancy in electrical conductivity data of amphiboles and to evaluate whether MLD could be caused by metasomatism, we determined the electrical conductivity of a natural metasomatized rock sample. The metasomatized rock sample consists of ~87% diopside pyroxene, ~9% sodium-bearing tremolite amphibole, and ~3% albite feldspar. We collected the electrical conductivity data at ~3.0 GPa, i.e., the depth relevant to MLD. We also spanned a temperature range between 400 to 1000 K. We found that the electrical conductivity of this metasomatized rock sample increases with temperature. The temperature dependence of the electrical conductivity exhibits two distinct regimes. At low temperatures <700 K, the electrical conductivity is dominated by the conduction in the solid state. At temperatures >775 K, the conductivity increases, and it is likely to be dominated by the conduction of aqueous fluids due to partial dehydration. The main distinction between the current study and the prior studies on the electrical conductivity of amphiboles or amphibole-bearing rocks is the sodium (Na) content in amphiboles of the assemblage. Moreover, it is likely that the higher Na content in amphiboles leads to higher electrical conductivity. Pargasite and edenite amphiboles are the most common amphibole varieties in the metasomatized mantle, and our study on Na-bearing tremolite is the closest analog of these amphiboles. Comparison of the electrical conductivity results with the magnetotelluric observations constrains the amphibole abundance at MLD depths to <1.5%. Such a low-modal proportion of amphiboles could only reduce the seismic shear wave velocity by 0.4–0.5%, which is significantly lower than the observed velocity reduction of 2–6%. Thus, it might be challenging to explain both seismic and magnetotelluric observations at MLD simultaneously. 

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