INVESTIGATION OF THERMAL CONDUCTIVITY OF SUPERCONDUCTING MATERIALS WITHIN THE TEMPERATURE RANGE FROM 4.2 TO 300 K

The thermoelectric properties of Nb-doped Zn4Sb3 compounds, (Zn1–xNbx)4Sb3 (x = 0, 0.005, and 0.01), were investigated at temperatures ranging from 300 to 685 K. The results showed that by substituting Zn with Nb, the thermal conductivities of all the Nb-doped compounds were lower than that of the pristine β-Zn4Sb3. Among the compounds studied, the lightly substituted (Zn0.995Nb0.005)4Sb3 compound exhibited the best thermoelectric performance due to the improvement in both its electrical resistivity and thermal conductivity. Its figure of merit, ZT, was greater than the undoped Zn4Sb3 compound for the temperature range investigated. In particular, the ZT of (Zn0.995Nb0.005)4Sb3 reached a value of 1.1 at 680 K, which was 69% greater than that of the undoped Zn4Sb3 obtained in this study.

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ON MEASUREMENT OF THERMAL CONDUCTIVITY AT HIGH TEMPERATURES

Canadian Journal of Physics ◽

10.1139/p61-112 ◽

1961 ◽

Vol 39 (7) ◽

pp. 1029-1039 ◽

Cited By ~ 3

Author(s):

M. J. Laubitz

Keyword(s):

Thermal Conductivity ◽

Heat Flow ◽

High Temperatures ◽

Mathematical Analysis ◽

Temperature Range ◽

Linear Heat ◽

Flow Systems

A method is given for exact mathematical analysis of linear heat flow systems used in measuring thermal conductivity at high temperatures. It is shown that a popular version of such a system is very sensitive to the alignment of its components, which seriously limits the temperature range of its satisfactory use.

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Calculation of the coefficient of thermal conductivity of a chemically reacting gas mixture of methane and hydrogen in the temperature range 1000?6000�K

Journal of Engineering Physics ◽

10.1007/bf00866003 ◽

1978 ◽

Vol 35 (1) ◽

pp. 773-777

Author(s):

A. N. Laktyushin ◽

T. V. Laktyushina ◽

O. I. Yas'ko

Keyword(s):

Thermal Conductivity ◽

Gas Mixture ◽

Temperature Range ◽

Coefficient Of Thermal Conductivity ◽

Chemically Reacting

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Measurements of the thermal conductivity of R11 and R12 in the temperature range 250?340 K at pressures up to 30 MPa

International Journal of Thermophysics ◽

10.1007/bf00503903 ◽

1992 ◽

Vol 13 (5) ◽

pp. 735-751 ◽

Cited By ~ 21

Author(s):

M. J. Assael ◽

E. Karagiannidis ◽

W. A. Wakeham

Keyword(s):

Thermal Conductivity ◽

Temperature Range

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Thermal Conductivity and Prandtl Number of Carbon Dioxide and Carbon-Dioxide Air Mixtures at One Atmosphere

Journal of Heat Transfer ◽

10.1115/1.3680490 ◽

1961 ◽

Vol 83 (2) ◽

pp. 125-131 ◽

Cited By ~ 12

Author(s):

Jerome L. Novotny ◽

Thomas F. Irvine

Keyword(s):

Carbon Dioxide ◽

Thermal Conductivity ◽

Prandtl Number ◽

Maximum Error ◽

Intermolecular Force ◽

Temperature Range ◽

Average Temperature ◽

Pure Carbon ◽

Prandtl Numbers ◽

Pure Carbon Dioxide

By measuring laminar recovery factors in a high velocity gas stream, experimental determinations were made of the Prandtl number of carbon dioxide over a temperature range from 285 to 450 K and of carbon-dioxide air mixtures at an average temperature of 285 K with a predicted maximum error of 1.5 per cent. Thermal conductivity values were deduced from these Prandtl numbers and compared with literature values measured by other methods. Using intermolecular force constants determined from literature experimental data, viscosities, thermal conductivities, and Prandtl numbers were calculated for carbon-dioxide air mixtures over the temperature range 200 to 1500 deg for mixture ratios from pure air to pure carbon dioxide.

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Thermal Conductivity of Si/SiGe Superlattices

10.1115/imece2001/htd-24397 ◽

2001 ◽

Author(s):

Scott T. Huxtable ◽

Alexis R. Abramson ◽

Arun Majumdar ◽

Chang-Lin Tien ◽

Chris LaBounty ◽

...

Keyword(s):

Thermal Conductivity ◽

Measurement Technique ◽

Unit Length ◽

Temperature Range ◽

Sige Alloy ◽

The Cross ◽

Superlattice Structures

Abstract The cross-plane and in-plane thermal conductivity of four Si/Si0.7Ge0.3 superlattice structures with periods from 45 Å to 300 Å are experimentally investigated using the 3-ω measurement technique. The experiment is conducted over a temperature range from 70 to 340 K. Results indicate that the cross-plane thermal conductivity decreases with decreasing period thickness (i.e. increasing number of interfaces per unit length). The superlattice with the shortest period exhibits a cross-plane thermal conductivity similar to that of a SiGe alloy. The in-plane thermal conductivity follows a similar decreasing trend with period thickness for the three larger period superlattices, but jumps to higher values for the shortest period superlattice. Additionally, the in-plane conductivity can be 3–4 times higher than the cross-plane value.

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