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The absolute Seebeck coefficient of platinum was determined from 80 to 340 K by direct comparsion to lead. Results of this comparison disagree with previous results which have been used for the calculation of absolute values for other materials. The thermal conductivity λ and electrical resistivity ρ of the lead standard were also determined. The electrical resistivity could be described with a modified Gruneisen-Bloch equation which allows for the effect of thermal expansion on the Debye temperature ΘD. The ratio λρ/T was within 1% of the Sommerfeld value of 2.443×10−8 (V/K)2 from 1.0 to 5.0 ΘD.

a b s t r a c tThe abundance of natural gas in the United States because of the number of existing natural gas reserves and the recent advances in extracting unconventional reserves has been one of the main drivers for low natural gas prices. A question arises of what is the optimal use of natural gas as a transportation fuel. Is it more efficient to use natural gas in a stationary power application to generate electricity to charge electric vehicles, compress natural gas for onboard combustion in vehicles, or re-form natural gas into a denser transportation fuel? This study investigates the well-to-wheels energy use and greenhouse gas emissions from various natural gas to transportation fuel pathways and compares the results to conventional gasoline vehicles and electric vehicles using the US electrical generation mix. Specifically, natural gas vehicles running on compressed natural gas are compared against electric vehicles charged with electricity produced solely from natural gas combustion in stationary power plants. The results of the study show that the dependency on the combustion efficiency of natural gas in stationary power can outweigh the inherent efficiency of electric vehicles, thus highlighting the importance of examining energy use on a well-to-wheels basis.

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A study of the factors which affect the thermal conductivity of αFe and its solutions is described. The results of these experiments define the phonon and electronic components of the thermal conductivity of pure αFe fairly well between 90 and 400 K. Also, the phonon conductivity can be analyzed to identify the strengths of electron-phonon and phonon-phonon scattering, and the latter resistance is in good agreement with theoretical estimates. The scattering of phonons by electrons is intermediate between the small values for noble metals and the strong scattering found in Nb and Ta. An experimental estimate of the electron-phonon mass enhancement factor, 0.4, is derived from the results. Finally, reexamination of the data for ten solid solution alloys suggests that both phonon-scattering mechanisms are influenced by the alloying elements.

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Rapid vehicle powertrain development has become a technological breakthrough for the design and implementation of vehicles that meet and exceed the fuel efficiency, cost, and performance targets expected by today's consumer. Recently, advances in large scale additive manufacturing have provided the means to bridge hardware-in-theloop with preproduction mule chassis testing. This paper details a case study from Oak Ridge National Laboratory bridging the powertrain-in-the-loop development process with vehicle systems implementation using big area additive manufacturing (BAAM). For this case study, the use of a component-in-the-loop laboratory with math-based models is detailed for the design of a battery electric powertrain to be implemented in a printed prototype mule. The ability for BAAM to accelerate the mule development process via the concept of computer-aided design to part is explored. The integration of the powertrain and the opportunities and challenges of doing so are detailed in this work. The results of the mule-vehicle chassis dynamometer testing are presented. Lastly, the ability to integrate more complex powertrains is discussed.

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