Browsing by Author "Su, J"

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    On the structure of α-BiFeO3
    (American Chemical Society, 2013-03-04) Wang, H; Yang, CX; Lu, J; Wu, MM; Su, J; Li, K; Zhang, JR; Li, GB; Jin, T; Kamiyama, T; Liao, FH; Lin, JH; Wu, YC
    Polycrystalline and monocrystalline α-BiFeO3 crystals have been synthesized by solid state reaction and flux growth method, respectively. X-ray, neutron, and electron diffraction techniques are used to study the crystallographic and magnetic structure of α-BiFeO3. The present data show that α-BiFeO3 crystallizes in space group P1 with a = 0.563?17(1) nm, b = 0.563?84(1) nm, c = 0.563?70(1) nm, α = 59.33(1)°, ? = 59.35(1)°, ? = 59.38(1)°, and the magnetic structure of α-BiFeO3 can be described by space group P1 with magnetic modulation vector in reciprocal space q = 0.0045a* ? 0.0045b*, which is the magnetic structure model proposed by I. Sosnowska(1) applied to the new P1 crystal symmetry of α-BiFeO3. © 2013 American Chemical Society
  • Thumbnail Image
    Item
    A study of the interaction between polyelectrolytes and biomolecules at the solid/solution interface with neutron specular reflectivity
    (International Conference on Neutron Scattering, 2017-07-12) Garvey, CJ; Raghuwanshi, VS; Su, J; Raverty, W; Holt, SA; Holden, PJ; Garnier, G
    Cellulose fibres may be formed into a low cost substrate, paper, for the adsorption of biomolecules to form the basis of cheap robust diagnostic tests. Important issues for the development of this technology are the retention of the biomolecules and maintaining the activity of the absorbed biomolecule. Typically the large internal surface is rough and there are limited experimental techniques to directly examine the structure of the adsorbed layer. In this work we describe our progress in using neutron and x-ray reflectivity to study the interaction between the cellulose surface and various adsorbed biomolecules with the aim to produce a model system to provide fundamental understanding for the production of robust paper based sensors. We have produced flat cellulose films from biodeuterated cellulose of varying degrees of non-exchangeable deuteration using bacterial cellulose produced with deuterated carbon sources. The films are amorphous with the fully hydrated films exhibiting 100% exchangeability of hydroxyl cellulose groups. The enhanced contrast, with respect to protein in particular, will allow visualisation of this class of molecules on the surface. The films are suitable for the visualisation of the diffuseness of a layer of cationic polyelectrolyte adsorbed to a cellulose surface. Giving, in principle,control on the charge sign and density of the cellulose surface for adsorption of biomolecules.