| 摘要 |
A new device for obtaining dust diffractograms from a single crystal through spreading of its orientation with simultaneous rotation about two axes (technique of Gandolfi), with an angle X between the axes which is optimized in order to achieve a maximum of orientations and a maximum diffraction angle up to when is recorded a total quantity of possible reflections. Mounted in a diffractometer or chamber with Debye-Scherrer geometry, the device causes the crystal, at the crossing of the two axes, to simulate a polycrystalline sample in order to produce a diffractogram similar to that of a powder, as used for the identification of crystalline materials. The device comprises the axis GC, its coupling to the axis FC of the diffractometer through a part which defines X, a mechanism to produce its rotation through friction at the bottom of the diffractometer and a mechanism which supports the crystal and provides for its centering in the diffractometer.
|
