Weissenberg geometry

Weissenberg geometry (Weissenberg 1924) is dealt with in the books by Buerger (1942) and Woolfson (1970) for example. This method is not 

The following sections Al.3.1 and Al.3.2 describe the standard situation where a layer-line screen is used. 

Normal-beam geometry (i.e. the X-ray beam being perpendicular to the rotation axis) is used to record zero-layer photographs. The film is held in a cylindrical cassette coaxial with the rotation axis. The centre of the gap in a screen is set to coincide with the zero-layer plane. The coordinate of a spot on the film measured parallel (ZF) and perpendicular (Yf) to the rotation axis is given by 

Upper-layer photographs are usually recorded in equi-inclination geometry (i.e.fi-— v, see equations (A1.8) and (A1.9)). The X-ray beam direction is made coincident with the generator of the cone of the dif- 

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The first protein structure to be solved using IP synchrotron data was that of amino acid pyruvate aminotransferase using Weissenberg geometry at the Photon Factory the scanner used was the BA-100 of Fuji (Watanabe et al 1989). 

At the Photon Factory data collection facilities for macromolecular crystallography have primarily been centred on either Weissenberg geometry or diffractometry. 

A cone and plate viscometer, such as the Ferranti-Shirley or the Weissenberg instruments, shears a fluid sample in the small angle (usually 4° or less) between a flat surface and a rotating cone whose apex just touches the surface. Figure 3f illustrates one such arrangement. This geometry has the advantage that the shear rate is everywhere uniform and equal io co/ sin, since the local cone velocity is cor and the separation between the... 

Another serious limitation on the magnitude of the torque is avoidance of the Weissenberg effect in which, owing to normal stresses (Section C below), the liquid climbs up the inner cylinder during rotation. This alters the geometry and falsifies the form factor b calculated from equation 7. Observation of the sample is therefore highly desirable to make sure that the torque is sufficiently small to render this effect negligible. 

For cone and plate geometry, the primary normal stress difference thrust force F tending to separate the two surfaces, and this can be measured by a force transducer as in the Weissenberg rheogo-niometer the relation is... 

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