Anisotropic In-Plane Strain and Transport in Epitaxial Nd(0.2)Sr(0.8)MnO(3) Thin Films

The structure, morphology, and electrical properties of epitaxial a-axis oriented thin films of Nd(0.2)Sr(0.8)MnO(3) are reported for thicknesses 10 nm <= t <= 150 nm. Films were grown with both tensile and compressive strain on various substrates. It is found that the elongated crystallographic c-axes of the films remain fully strained to the substrates for all thicknesses in both strain states. Relaxation of the a and b axes is observed for t>= 65 nm with films grown under tensile strain developing uniaxial crack arrays (running along the c axis) due to a highly anisotropic thermal expansion. For the latter films, the room-temperature in-plane electrical resistivity anisotropy, rho_b/rho_c, increases approximately exponentially with increasing film thickness to values of ~1000 in the thickest films studied. Films under tension have their Neel temperatures enhanced by ~25 K independent of thickness, consistent with an enhancement of ferromagnetic exchange along their expanded c axes.Comment: 14 pp., 9 Fig.

Ground states and formal duality relations in the Gaussian core model

We study dimensional trends in ground states for soft-matter systems. Specifically, using a high-dimensional version of Parrinello-Rahman dynamics, we investigate the behavior of the Gaussian core model in up to eight dimensions. The results include unexpected geometric structures, with surprising anisotropy as well as formal duality relations. These duality relations suggest that the Gaussian core model possesses unexplored symmetries, and they have implications for a broad range of soft-core potentials.Comment: 7 pages, 1 figure, appeared in Physical Review E (http://pre.aps.org

Plasmatron Reformation of Renewable Fuels

The characteristics of plasmatron reformers for the generation of hydrogen rich gas using renewable fuels is discussed. Biodiesel and ethanol have been investigated. Operating as a function of the air/fuel ratio is evaluated, as well as the impact of the plasma. I

Experimental Investigation of Plasma Assisted Reforming of Propane

Plasmatron fuel converters have been investigated for the conversion of a wide range of fuels. This paper is one of a series of paper investigating the performance of plasmatron reformers. In this paper a systematic experimental investigation is carried out of the reformation of propane in a plasmatron fuel reformer. The effect upon reformation of flow rate distribution and electrical power level are investigated for a given geometry that has been thoroughly studied with a similar gaseous fuel, methane. A limited set of startup experiments with propane are discussed 1

Experimental Investigation of Plasma Assisted Reforming of Methane I: Steady State Operation

Plasmatron fuel converters have been investigated for the conversion of a wide range of fuels. This paper is one of a series of paper investigating the performance of plasmatron methane reformers. In this paper a systematic experimental investigation is carried out of the reformation of methane in a plasmatron fuel reformer at steady state conditions. The effect upon reformation of flow rate distribution and electrical power level are investigated for a given geometry that has been thoroughly studied with a similar gaseous fuel, propane. Startup issues are investigated in an accompanying paper. 1