The Construction Of A Stability Monitor System For Beijing Synchrotron Radiation Facility And The Research On The Biological Macromolecules By Using Small-angle X-ray Scattering

Beijing Synchrotron Radiation Facility (BSRF) is a powerful synchrotron radiation source which wavelength range from vacuum ultraviolet to hard x-ray, and play a significant role in many scientific domains such as biophysics, biochemistry, solid physics, atom and molecule physics, surface physics, material physics, standard measurement, Lithography, medicine and so on. This thesis is main concerning the development of BSRF. The content is divided into two parts:First part's topic is the construction of the stability monitor system for BSRF. Considering the quality of experimental data is affected by the instability of the incident beam light frequently, we construct a stability monitor system, which includes beamline stability monitor system and front ends stability monitor system, to monitor the beam's position and the intensity. In this part, we firstly present our new invented algorithms which aim to improve the precision of the double-wires beam position monitor (BPM) and double-blades BPM, and then describe the methods and the structure of the beamline stability monitor system and front ends monitor system. According to the monitor results, the stability status of the BSRF and the effect of the slow feedback system of the electron beam's orbit are also discussed.Second part's topic is the small-angle x-ray scattering methods to study biological macromolecules. As the small-angle x-ray scattering (SAXS) is considered as a powerful tool in the study of biological macromolecules in recent years, we constructed a new small-angle x-ray scattering beamline named 1W2A at BSRF during the years of 2006 and 2007. In this part, the structure and the characteristics of this new beamline are present firstly, and then the special experiment setup and the experimental raw data's processing methods which we have constructed to suit to the biological macromolecules studies are also presented and discussed. In order to rectify our experiment setup and processing methods, the structures of two monomers (include bovine serum albumin and mitogen-activated protein kinase kinase kinase 3) and two complexes (include ribosome70S from E. coli and ribosome80S from yeast) which have known crystal structure are investigated. The low resolution 3-D structures of the monomers are obtained by using ab initio methods, and the atomic resolution 3-D structures of the complexes are obtained by using rigid body refinement methods. All of the structures are fitting their crystal structures very well indicate that the small-angle x-ray scattering's experiment setup and methods at 1W2A station which for the studies of the biological macromolecules' structure are constructed successfully.