Influence of thermal conductivity on the dynamic response of magnetocaloric materials

We compare the magnetocaloric effect of samples prepared with different thermal conductivities to investigate the potential of composite materials. By applying the magnetic field under operating conditions we test the material’s response and compare this to heat transfer simulations in order to check the reliability of the adiabatic temperature change probe used. As a result of this study we highlight how the material’s thermal conductivity influences τ , the time constant of temperature change. This parameter ultimately limits the maximum frequency of a refrigerant cycle and offers fundamental information about the correlation between thermal conductivity and the magnetocaloric effect

N-body simulations of the Magellanic Stream

A suite of high-resolution N-body simulations of the Magellanic Clouds -- Milky Way system are presented and compared directly with newly available data from the HI Parkes All-Sky Survey (HIPASS). We show that the interaction between Small and Large Magellanic Clouds results in both a spatial and kinematical bifurcation of both the Stream and the Leading Arm. The spatial bifurcation of the Stream is readily apparent in the HIPASS data, and the kinematical bifurcation is also tentatively identified. This bifurcation provides strong support for the tidal disruption origin for the Magellanic Stream. A fiducial model for the Magellanic Clouds is presented upon completion of an extensive parameter survey of the potential orbital configurations of the Magellanic Clouds and the viable initial boundary conditions for the disc of the Small Magellanic Cloud. The impact of the choice of these critical parameters upon the final configurations of the Stream and Leading Arm is detailed.Comment: Accepted by MNRAS, 07 Jun 2006. 14 pages, 14 figures, 3 tables. LaTeX (mn2e.sty). File with decent resolution images (strongly recommended) available at http://astronomy.swin.edu.au/~tconnors/publications/ . References added; distance and HI-LOres difference figures added; clearer figures; discussion added to, but conclusions unchange

Thermal properties of UPdSn and UCuSn

The authors report on the specific-heat and the thermopower of UPdSn and UCuSn, both of which order antiferromagnetically at low temperatures. Both compounds show similar behavior in the specific heat, and the large magnetic-entropy changes around T{sub N} are evidence for a large degree of 5f-electron localizations. The thermopower, on the other hand, behaves very different in the two compounds. While prominent features are seen in the temperature dependence of the thermopower of UCuSn, only weak changes are observed for UPdSn. This may indicate that, for these compounds, the thermopower response is due to mechanisms other than purely magnetic ones

Plasmas and Controlled Nuclear Fusion

Contains reports on thirteen research projects split into three sections.National Science Foundation (Grant GK-2581