Device Fabrication and Measurement: The thermally crosslinkable organic gate insulator, a thermally crosslinkable polyvinylphenol derivative (Samsung proprietary), was spin cast from cyclohexanone solution on top of the AlNd gate substrate and then cured on a hot plate at 150 C for 1 h. The thickness of the organic insulator was~550 nm. After thermal curing, the organic insulator was insoluble in organic solvents. To fabricate a top-contact transistor, the soluble fullerene derivatives were spin cast from the chlorobenzene solution to form a 70±110 nm thick layer (1000±2000 rpm with~1 wt.-% solution) and then dried on a hot plate at 70±80 C for 3 h under vacuum. The source±drain metals (Ca, Mg, Al, Ag, and Au) were then deposited by vacuum shadow evaporation to complete the device. 250 nm thick Al and Ag protective layers were deposited to prevent oxidation on top of the 10 nm Ca and Mg, respectively. Practically all of the fabrication process was performed under an inert (N 2 ) atmosphere and vacuum to avoid exposure of the fullerene derivatives to air. The device test was performed immediately after the device fabrication in air and was finished in no more than 30 min. To fabricate a bottom-contact device, the source±drain metal electrodes were deposited on top of the organic insulator before the deposition of the organic semiconductor. We did not perform any surface treatment on the source±drain metal electrodes in bottom-contact geometry. For the bottom-and top-contact geometry, the channel length (L) was 100 lm and the channel width (W) was 1 mm. Source±drain currents were measured using a Keithley Semiconductor Analyzer (4200-SCS). The source±drain current (I D ) is governed by the equation:where C i is the capacitance per unit area of the gate insulator layer, V G is the gate voltage, V T is the threshold voltage, and l is the fieldeffect mobility. The mobility (l) was calculated from the slope of the plot of (½I D ½) 1/2 versus V G in the saturation regime. Holographic gratings can be recorded on both amorphous and liquid-crystalline (LC) polymers through photoisomerization or photochemical phase transition of chromophores, [1±7] and have potential applications in information technology.[3±11] Generally, the diffraction efficiency (DE) is one of the most important parameters for holographic gratings, whose control and stability have become the focus of scientific research. Alteration of the chemical structure of materials has often been adopted, although it requires a large amount of synthetic work. Recently, gain effects, [4] mechanical stretch, [6a] electrical switch, [12] self-assembly, [6b] mixing with liquid crystals, [7a] and crosslinking [7b] have been explored to improve the DE. However, the technique of phase separation has not yet been adopted. Although this method may be simple and effective, phase separation is usually micrometer-or submicrometer-scaled and cannot be applied directly due to serious scattering of visible light, which decreases the DE. If the phase domain size is reduc...

Sucked into the vortex: Hydrogels with embedded Rhodamine B dye showed stir-induced circularly polarized luminescence (CPL; see picture), the sense of which can be controlled by switching the stir direction from clockwise (CW) to counterclockwise (CCW) with slow cooling from the sol to gel states. The chiral alignment of the dye was erased by heating the sample above the gel-sol transition temperature.

This paper presents results of conceptual design activities and associated R&D of a solid breeder blanket system for demonstration of power generation fusion reactors (DEMO blanket) cooled by supercritical water. The Fusion Council of Japan developed the long-term research and development programme of the blanket in 1999. To make the fusion DEMO reactor more attractive, a higher thermal efficiency of more than 40% was strongly recommended. To meet this requirement, the design of the DEMO fusion reactor was carried out. In conjunction with the reactor design, a new concept of a solid breeder blanket cooled by supercritical water was proposed and design and technology development of a solid breeder blanket cooled by supercritical water was performed.By thermo-mechanical analyses of the first wall, the tresca stress was evaluated to be 428 MPa, which clears the 3Sm value of F82H. By thermal and nuclear analyses of the breeder layers, it was shown that a net TBR of more than 1.05 can be achieved. By thermal analysis of the supercritical water power plant, it was shown that a thermal efficiency of more than 41% is achievable. The design work included design of the coolant flow pattern for blanket modules, module structure design, thermo-mechanical analysis and neutronics analysis of the blanket module, and analyses of the tritium inventory and permeation. Preliminary integration of the design of a solid breeder blanket cooled by supercritical water was achieved in this study.In parallel with the design activities, engineering R&D was conducted covering all necessary issues, such as development of structural materials, tritium breeding materials, and neutron multiplier materials; neutronics experiments and analyses; and development of the blanket module fabrication technology. Upon developing the fabrication technology for the first wall and box structure, a hot isostatic pressing bonded F82H first wall mock-up with embedded rectangular cooling channels was successfully fabricated. It withstood the high heat flux test at 2.7 MW m−2. Also, a correlation parameter of the Li2TiO3 pebble bed made by the sol–gel method was verified by measurement of the thermal conductivity of the breeder pebble bed, which is one of the most important design data.

Novel liquid-crystalline polymers (LCPs) containing a long azotolane moiety were synthesized, and the relationship between the chemical structures and the photoresponsive behavior was investigated. All homogeneously aligned LCP films exhibited extremely high values of birefringence (Deltan) in the wide wavelength range. Specifically, the azotolane LCP with two azobenzene units showed the most efficient change in the alignment of the azotolane moiety with a huge change in Deltan (>/=0.65). This means that the high value of Deltan in the homogeneously aligned state can be converted to the change in Deltan effectively.