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Engineering topics

Hill, D. W.

Publications and source records attributed to Hill, D. W..

Extended-magnetohydrodynamics in under-dense plasmas

Extended-magnetohydrodynamics (MHD) transports magnetic flux and electron energy in high-energy-density experiments, but individual transport effects remain unobserved experimentally. Two factors are responsible in defining the transport: electron temperature and electron current. Here, each electron energy transport term has a direct analog in magnetic flux transport. To measure the thermally driven transport of magnetic flux and electron energy, a simple experimental configuration is explored computationally using a laser-heated pre-magnetized under-dense plasma. Changes to the laser heating profile precipitate clear diagnostic signatures from the Nernst, cross-gradient-Nernst, anisotropic conduction, and Righi-Leduc heat-flow. With a wide operating parameter range, this configuration can be used in both small and large scale facilities to benchmark MHD and kinetic transport in collisional/semi-collisional, local/non-local, and magnetized/unmagnetized regimes.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Chemical studies of Apollo 16 and 17 samples

Instrumental neutron activation analyses were conducted to nine Apollo 16 samples and 23 Apollo 17 samples. Radiochemical neutron activation analyses were carried out in the case of six Apollo 16 boulder-2 rocks, five Apollo 17 soils, and one Apollo 16 soil. The elemental abundances obtained are presented in tables and the significance of the analytical results is discussed. Attention is also given to interelement correlations.

Laul, J. C.↗