RESUMEN
Bio-semiconductors are expected to be similar to organic semiconductors; however, they have not been utilized in application yet. In this study, we show the origin of electron appearance, N- and S-type negative resistances, rectification, and switching effects of semiconductors with energy storage capacities of up to 418.5 mJ/m2 using granulated amorphous kenaf cellulose particles (AKCPs). The radical electrons in AKCP at 295 K appear in cellulose via the glycosidic bond C1-O1·-C4. Hall effect measurements indicate an n-type semiconductor with a carrier concentration of 9.89 × 1015/cm3, which corresponds to a mobility of 10.66 cm2/Vs and an electric resistivity of 9.80 × 102 Ωcm at 298 K. The conduction mechanism in the kenaf tissue was modelled from AC impedance curves. The light and flexible cellulose-semiconductors may open up new avenues in soft electronics such as switching effect devices and bio-sensors, primarily because they are composed of renewable natural compounds.
RESUMEN
We have developed a new neutron phase imaging system with a Talbot-Lau interferometer for utilization at the CN-3 port of the Kyoto University Reactor. To achieve efficient differential-phase imaging and visibility (dark-field) imaging at this beamline, we adopted a relatively shorter design wavelength of 2.7 Å. By fabricating neutron absorption gratings with thick gadolinium absorbers, we were able to obtain clear moiré fringes with a high visibility of 55% for thermal neutrons. As a demonstration of its imaging capabilities for expanded actual utilization in the medium-sized sources, we observed additively manufactured rods of Inconel 718. Using visibility imaging, we successfully examined variations in the size of defects in the rods caused by hot isostatic pressing process. In addition, we conducted tomography measurements of the rods, which allowed us to reveal the spatial distribution of defects at sub-micrometer scales.