How to apply the small-angle X-ray scattering (SAXS) and neutron scattering (SANS) to colloidal, micellar and polymeric systems in solution was described. The principles and methods to determine the size and shape of particles in solution and dispersion, and also to estimate the solution structure were explained from the basic point of view.
The 2.8Å crystal structure of the novel multiple-heme enzyme, hydroxylamine oxidoreductase from a nitrifying chemoautotrophic bacterium, Nitrosonnonas europaea, is described. Twenty-four hemes lie in the center bottom of the trimeric molecule, localized in four clusters within each monomer. The heme clusters within the trimer are aligned to form a ring that has inlet and outlet sites. The inlet occupied by the novel heme, heme P460. The structure suggests pathways by which ‘dielectron transfer’ may occur through the precisely arranged hemes.
Diffusion of cations (self-, impurities) in single-crystal MgO have been studied. The diffusion penetration profiles were obtained with the aid of a secondary ion mass spectrometry (SIMs) . The diffusion profiles contained lattice and dislocation diffusion contributions. The temperature dependence of lattice and dislocation diffusion for 16 species has been determined. The dislocation diffusion coefficients were 4 to 6 orders of magnitude larger than those of lattice diffusion, although the activation energies for lattice and dislocation diffusion on the same element were not so different. A linear correlation between pre-exponential factor and activation energy for lattice and dislocation diffusion has been confirmed. The elements were separated into two trends of lines by the geometrical condition. The slope of these lines on lattice and dislocation diffusion corresponds with that expected from Zener's elastic theory.
The article reviews the recent determination of the magnetic structures of an [Fe/Gd] 15 multilayer by the authors using resonant magnetic scattering of circular polarized x-rays at synchrotron sources.The specular reflections reveal that the 5.4-nm-thick Gd layers magnetize highly nonuniformly along the out-of-plane direction in both magnitude and azimuthal angle in the aligned and twisted states of the sample. The decay of the qx-scan magnetic diffuse scattering evidences much smoother magnetic interfaces than the charge interfaces.The qz-dependent difference diffuse peaks suggest the presence of rough magnetic interfaces within the Gd layers.