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Active control of the resistive wall modes (RWMs) is analysed for the feedback system with internal correction coils (ICs). The analysis is performed using a single mode thin-wall model in the cylindrical approximation and proportional control. Three cases are considered: with radial field sensors, poloidal field sensors inside the vessel and poloidal sensors outside. It is shown that, within the model, the systems with such sensors and proportional feedback have similar characteristics. The feedback systems with internal and external correction coils are compared and advantages of the IC system are shown.

We present incoherent quasi-elastic neutron scattering measurements in a wave vector transfer range from 0.4 Å(-1) to 1.6Å (-1) on liquid n-hexane confined in cylindrical, parallel-aligned nanochannels of 6 nm mean diameter and 260 μm length in monolithic, mesoporous silicon. They are complemented with, and compared to, measurements on the bulk system in a temperature range from 50 K to 250 K. The time-of-flight spectra of the bulk liquid (BL) can be modeled by microscopic translational as well as fast localized rotational, thermally excited, stochastic motions of the molecules. In the nano-confined state of the liquid, which was prepared by vapor condensation, we find two molecular populations with distinct dynamics, a fraction which is immobile on the time scale of 1 ps to 100 ps probed in our experiments and a second component with a self-diffusion dynamics slightly slower than observed for the bulk liquid. No hints of an anisotropy of the translational diffusion with regard to the orientation of the channels' long axes have been found. The immobile fraction amounts to about 5% at 250 K, gradually increases upon cooling and exhibits an abrupt increase at 160 K (20 K below bulk crystallization), which indicates pore freezing.

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