X-ray diffraction synchrotron radiation

Ueno, S., Yano, J., Seto, H., Amemiya, Y., Sato, K. 2000. Synchrotron radiation X-ray diffraction study of polymorphic crystallization in triacylglycerols. In, Physical Properties of Fats, Oils and Emulsifiers (N. Widlak, ed.), pp. 64-78, AOCS Press, Champaign. 

FIGURE 5.17 Cellulose diffraction patterns. Top left synchrotron radiation x-ray diffraction pattern for cotton fiber bundle. The fiber was vertical and the white circle and line correspond to a shadow from the main beam catcher and its support. (Credit to Zakhia Ford.) Top right electron diffraction pattern of fragments of cotton secondary wall. The much shorter arcs in the top right figure are due to the good alignment and small number of crystallites in the electron beam. (Credit to Richard J. Schmidt.) Bottom a synthesized powder pattern for cellulose, based on the unit cell dimensions and crystalline coordinates of Nishiyama et al. [209]. (Credit to Zakhia Ford.) Also shown are the hkl values for the Miller indices. The 2-theta values are for molybdenum radiation instead of the more commonly used copper radiation. 

Figure 9. Synchrotron-radiation X-ray diffraction patterns of polymorphic transformation of trielaidin taken during temperature variation shown in an inserted figure (unit, nm). Q wave vector.

Figure 17. Time-resolved synchrotron radiation X-ray diffraction patterns of concentration ratio LLL/PPP = 60/40. At left is the temperature change with time (unit nm).

As for the polymorphism of milkfat, a and p forms frequently appear, and p form appears under special conditions when HMF and milkfat are stored for long duration (99-101). In regard to the effects of thermal treatment and emulsification on the polymorphic crystallization of milkfat, Lopez et al. recently performed synchrotron radiation X-ray diffraction and DSC studies, using anhydrous milkfat... 

As for the effects of the shear stress, it was shown by a Synchrotron radiation X-ray diffraction study that transformations from metastable to more stable forms, especially to Form V, were accelerated by high shear stress (110). Figure 25 shows the time variation of relative intensities of X-ray diffraction peaks of CB crystals formed after cooling from 50°C to 18°C at a rate of 3°C/min. In the case of no shear. Form III appeared at first after the temperature reached at 18°C, and then Form IV crystallized at the expense of Form III. On the other hand, applying the shear stress at 1440 s caused accelerated transformation from Form III to Form V, without the occurrence of Form IV. The same result was observed with lower shear rates (19), and the persistence time of Form III was reduced as the shear rate was increased. Mazaanti et al also observed that the orientation of CB crystals are aligned with the shear flow (110). These results indicated that temperature and shear treatments are the tools for tailoring the desired polymorphic structures of fats. 

In SLS, the polymorphic transformation from a to y proceeded quite fast, because thermal energy easily accelerated the transformation between the two forms having rather low melting points. Therefore, Synchrotron radiation X-ray diffraction (SR-XRD) was employed to monitor the transformation process, since... 

Fig, 10. In situ Synchrotron radiation X-ray diffraction spectra of a-y transformation and melting of y of SLS (unit, nm). See Figure 9 for abbreviation. 

Higami, M., Ueno, S., Segawa, T., Iwanami, K., and Sato, K. (2003). Simultaneous synchrotron radiation X-ray diffraction—DSC analysis of melting and crystallization behavior of trilauroylglycerol in nanoparticles of oil-in-water emulsion. /. Am. Oil Chem. Soc. 80, 731-739. 

Among the techniques utilized for investigating water management in PEMFCs, synchrotron radiation x-ray diffraction has been demonstrated to be a snit-able tool to observe the real-time water dynamics in the polymeric membranes. 

Huq et al. (2001) have tentatively identified goyazite in Punic cosmetic pigments using synchrotron radiation X-ray diffraction (SR-XRD) techniques. 

Riekel, C., Madsen, B., Knight, D., and Vollrath, F. (2000). X-ray diffraction on spider silk during controlled extrusion under a synchrotron radiation X-ray beam. Biomacromolecules 1, 622—626. 

Fig. 7. A typical X-ray diffraction pattern of the Fepr protein fromZJ. vulgaris (Hil-denborough). The pattern was recorded on station 9.6 at the Synchrotron Radiation Source at the CCLRC Daresbury Laboratory using a wavelength 0.87 A and a MAR-Research image-plate detector system with a crystal-to-detector distance of 220 nun. X-ray data clearly extend to a resolution of 1.5 A, or even higher. The crystal system is orthorhombic, spacegroup P2i2i2i with unit cell dimensions, a = 63.87, b = 65.01, c = 153.49 A. The unit cell contains four molecules of 60 kDa moleculEu- weight with a corresponding solvent content of approximately 48%.

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