Structural change of a phase-separated block copolymer thin film with polystyrene (PS) and poly (2-vinylpyridine) (P2VP) in contact with different solvents was observed by in-situ neutron reflectometry using a conventional cell for a solid/liquid interface, and time evolution of phase-separated structure after a temperature jump to 200℃ was observed for diblock and triblock copolymer thin films of PS and P2VP by grazing-incidence small-angle X-ray scattering (GISAXS). When PS-P2VP diblock copolymer thin film was contacted with methanol and water, the structural change was induced by penetration of small amount of the solvent into the film, and the original structure was almost recovered after drying it. Also, the diblock copolymer thin film was easily dissolved into toluene, and the original structure was never recovered after the solvent contact. After the temperature jump the lateral correlation spots were evolved with a time in the GISAXS pattern similarly for either block copolymer thin film with spherical structure, though their as-spun states were different.
Ionic diffusion paths are important for the ion-diffusion mechanism in the ionic conducting ceramic materials. Here we present a brief review on the ionic diffusion paths in some ionic conducting ceramic materials. In the fluorite-structured ionic conducting ceramics such as bismuth oxide-based materials, a similar curved diffusion pathway is observed along the ＜100＞ directions. In the ionic conductors with the cubic ABO3 perovskite-type structure such as (La0.8Sr0.2)(Ga0.8Mg0.15Co0.05)O3-δ, the mobile ions diffuse along a curved line keeping the interatomic distance between the B cation and O2- anion to some degree. The structure and diffusion path of K2NiF4-type (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ and apatite-type La9.69(Si5.70Mg0.30)O26.24 are also presented.
Water in plants is one of the most important factors for life. Water availability, water distribution and water flow also regulate various plant physiological phenomena. However, non-destructive methods for the in-situ study of water transport are quite limited. Neutron Radiography (NR) seem to be appropriate methods to study water distribution in intact plants. Also the combination of NR with the low-contrast tracer D2O allows the direct visualization of water flow and the calculation of water flow rates in plants with a high resolution at the tissue level. This article gives general introduction into those two methods and report about most recent results of our experiments in this field.
Neutron radiography is one of a useful non-destructive methods based upon the fact that the neutron beam is attenuated due to the interaction of neutrons with the nuclei of the atoms in the object materials. With this method, not only the transmission analysis with highly spatial resolution and time resolution, but also monitoring of transport processes of moisture and hydrogenous liquids in porous materials is enabled. This article reviews some researches to apply this technique in architecture field.