Figure 1.

Beamline schematic. (a) BioCAT beamline schematic; parts (b–(d) are possible sample mounts/options at the position labeling ‘Sample’. (b) Cryo-jet that operates without a gas shield and plunge-cooled sample. Note that there is no ice build-up at the nozzle while there is ice building up on the sample outside of the cryo-jet stream, although the sample at the beam position is cryo-preserved and ice-free in this image. (c) Cryo-stream that operates with a gas shield to prevent icing; note that the sample is dried by the very low humidity gas shield, even within part of the sample that is within the cryo-stream. (d) Example of a room-temperature sample enclosure, designed to preserve the sample against dehydration with two sections so that multiple samples can be scanned (one after the other) per sample mount change during an experimental run.