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Anisotropy of attenuation of acoustic waves in photorefractive BSO and BGO crystals has been studied in the frequency range of 0.4−1.6 GHz. The anisotropy parameters determined by the imaginary constants of BSO and BGO crystals are equal 0.58 and 0.52, respectively. It is shown that the most contribution of dielectric loss to the attenuation of acoustic waves is observed for the piezoactive transversal waves propagating in the (100) plane.

Propagation velocity and attenuation coefficient of acoustics waves in paratellurite crystals were measured by Bragg diffraction of light in the frequency range of 0.4–1.6 GHz. These results were used for calculation of real and imaginary components of the complex tensor of elastic constants. The analysis of the anisotropy of attenuation was carried out for the acoustic waves of different polarization propagating in the crystallographic planes, which are orthogonal to symmetry axes of second and forth order. The strongest anisotropy of acoustic attenuation and phase velocity is observed for the transverse acoustic waves propagating in the plane (1-10). It is shown that the attenuation reduces the integral efficiency of diffraction in several times in the acousto-optic deflector in which is used an oblique cut of paratellurite and the transverse acoustic wave propagating at an angle of 6 degrees to the [110] axis in the plane (1-10).

The three Phase I MX beamlines have been built for state of the art high-throughput data collection on crystals of biological macromolecules and are now well in their fourth year of operation. High quality results have been obtained. Further improvement of the beamlines is ongoing with a focus of automating and streamlining as many components and experimental processes as possible, from beam conditioning to user interaction and data analysis but maintaining experimental flexibility. Therefore, we are redesigning the end-station table, beam conditioning components and sample environment with the aim to add new and improved features. The system is also designed for ease of maintenance and keeps adaptability to future scientific requirements for the structural biology community. Delivery of the new end-stations is due to begin towards the latter half of 2010. Further plans include the provision of an improved software user interface, fast sample screening, remote access and category 3 pathogenic sample handling (I03). An update on these developments will also be presented.