The patterning characteristics of a variety of resist material platforms were investigated using a KrF laser ablation process. The results showed that a fullerene-based resist material with a 170-nm ...film thickness is capable of sub-micron resolution up to 0.8 μm 1:1 lines and spaces (L/S). Moreover, using a novolac-based resist material, the dependence of laser ablation patterning performance on the resist process conditions was determined. An increase in the total exposure energy (exposure energy per pass × total number of passes) is necessary as the film thickness increases. Moreover, using the same novolac-based resist material fixed at a 5-μm film thickness, results suggested that exposure energy has a more significant impact on the effective formation of laser ablation patterns (compared to number of exposure passes). Finally, preliminary investigations using a metal resist (at a 90-nm film thickness) resulted in resolution capabilities up to 2 μm 1:1 L/S at a relatively lower total exposure energy. This showed the potential of the metal resist material for application in laser ablation patterning.
The construction of a final focusing superconducting magnet system for SuperKEKB has been completed. The superconducting magnet system consists of eight quadrupole magnets, four superconducting ...compensation solenoids, and 43 corrector coils. These magnets are installed in two cryostats, QCS-L and QCS-R. The QCS-L and QCS-R are inserted into the particle detector, Belle-II, which has a superconducting solenoid of 1.5 T. In order to eliminate the influence of the Belle-II solenoid field on the collision beam and to achieve the required high luminosity, four superconducting compensation solenoids are excited to produce a magnetic field in the opposite direction of the Belle-II solenoid field. One of the longest superconducting compensation solenoids, named ESR1, is installed in QCS-R. The ESR1 consists of 15 coils. The coil design and excitation test of the ESR1 are presented in this paper. The experimental and analysis results of the quench characteristic are also discussed.
The beam final focus system in the SuperKEKB interaction region consists of 55 superconducting magnets including eight main quadrupole magnets. Two cryostats for these magnets were required to be ...operated inside the Belle-II particle detector because of the magnet positions by the SuperKEKB beam optics. The cryostats were designed under constraints of the space and the electromagnetic forces with Belle-II. Construction of the cryostats was completed, and they were installed into the SuperKEKB interaction region. Cold tests of the cryostats were performed, and all magnets were successfully excited at the operation currents. In this paper, the design and the construction of the cryostats are presented.
The construction of SuperKEKB, which consists of 7 GeV electron and 4 GeV positron main rings, is now going on. The final focus superconducting quadrupole magnets in the interaction region have been ...designed and constructed. From the field qualities of the prototype magnets, the magnet designs were modified, and the manufacturing and assembling methods of the coils were changed to satisfy the design values. The field measurements of the magnets were performed at room temperature, and confirmed that they were acceptable for the beam operation. In the paper, the design and the construction of the final focus quadrupole magnets, QC1, which will be located at the closest position to the beam interaction point, are presented.
Using rice grains contaminated with radioactive cesium (134Cs and 137Cs) that was released by the Fukushima Daiichi Nuclear Power Plant Accident in March of 2011, we investigated the behaviors of the ...radioactive cesium and potassium (total K and 40K) during sake brewing. Cesiumis a congener of K, and yeast cells have the ability to take up Cs using known K transporters. During rice polishing, the concentrations of radioactive Cs and K in the polished rice grains decreased gradually until a milling ratio (polished rice weight/brown rice weight) of 70% was reached. No significant changes were observed below this milling ratio. Sake was brewed on a small scale using the 70% polished rice. The transfer ratio of radioactive Cs to sake and to the sake cake was significantly different than the ratio of K. Approximately 36% and 23% of radioactive Cs in the polished rice was transferred to the sake and sake cake, respectively; however, 40% was removed by washing and steeping the rice grains. On the other hand, 25% and 40% of K in the polished rice was recovered in the sake and sake cake, respectively, and 35% was removed by washing and steeping the rice grains. From the present results, the concentration of radioactive Cs in sake would be 4 Bq/kg fresh weight, which is well below the regulation values (100 Bq/kg), even using brown rice containing 100 Bq/kg of radioactive Cs.
The applicability of several nitride powders for use as foaming agents in superplastically foaming ceramics was investigated. Ceramic mono-foams were fabricated successfully using AlN and Si3N4 ...foaming agents. By using BN as a foam agent, on the other hand, we cannot fabricated well developed ceramic foams due to cracking and fracture. When the quantity of foaming agent was increased, the porosity increased to a certain amount, then saturated. With equal amounts of Si3N4, the porosity from the dispersed foaming agent was higher than that obtained from a monolithic compact without mixing, which was similar to the case of SiC foam agent.
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