Abstract:
Experiments are carried out on rapid heating by an electric current pulse of plates for anisotropic graphite and gadolinium foil clamped in the same way: between two thick-walled plates of TF-$5$ glass (heavy flint). In both cases, the glass cells were previously compressed with a clamp to create some initial pressure. During the passage of the current pulse $(5~\mu$s$)$, the pressure in the samples is estimated; it increases due to thermal expansion when confined by the glass plates. The electrical resistance of liquid carbon at low pressures $($up to $1$ kbar$)$ increases with increasing temperature, just as for most conductors. Under limited expansion (increasing pressure), the electrical resistance of liquid carbon becomes constant, independent of the increase in temperature and pressure $($up to $9000$ K$)$. Unlike carbon, the electrical resistance of liquid gadolinium at elevated pressure $($about $1$ kbar$)$ practically did not change $(\sim260~\mu$m cm$)$ and remained approximately constant, as at lower pressures $(\sim0.34$ kbar$)$; and at high temperatures, up to $6000$ K.
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