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![[Figure 1]](hi5594fig1mag.jpg)
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Figure 1
Set-up for microbeam SAXS/WAXS measurements of frozen biological samples. (a) Schematic diagram of the cross section of the modified cryochamber. cb, cooled block; dp, super-invar tubing with the defining pinhole on top; fs, frozen sample; gp, super-invar tubing with the guard pinhole on top; ld, lid for specimen exchange; sh, specimen holder made of copper; vc, vacuum chamber. Upstream is on the left-hand side of the drawing. (b) Schematic diagram of the arrangement of components. bp, brass plate to cover the imaging plate except for the fan-shaped opening; cc, cryochamber; ip, cassette for the imaging plate attached to a motorized rotating stage on its back (not drawn); vb, vacuum beam path leading to the SAXS detector. (c) Method of adapting a specimen-bearing brass rod to the specimen holder. The specimen is a flight muscle fiber or fiber bundles, initially ∼2 mm in length and ∼200 µm in diameter. In its cross section, myofilamens are arranged in a hexagonal lattice with a unit-cell size of ∼45 nm. After freezing, this specimen is trimmed to leave a central straight segment of ∼500 µm in length. br, brass rod; cs, cross section; pp, piece of paper. (d) Diagram for heat transfer from the irradiated area of the specimen (shaded circle) to the brass rod, which is kept at ∼70 K and serves as a heat sink. This geometry is used to estimate the thermal effect of microbeam irradiation (see Appendix A). It is assumed that the effective surface of heat conduction is half of the surface area of the irradiated volume (black arc). It is also assumed that the distance between the irradiated area and the brass rod (L) is 500 µm and that the space between them is filled with ice. The arrows indicate the flow of heat. ia, irradiated area. |
![[Figure 1]](hi5594fig1.jpg)
 | JOURNAL OF SYNCHROTRON RADIATION |
ISSN: 1600-5775
