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The size of cellulose microfibril (CMF) bundles varies to interact with glucomannan/galactoglucomannan (GM/GGM). Arabino-4-O-methylglucuronoxylan (AGX) bonded CMF bundles coated with GM/GGM also have important roles in elaborating the distance between these components. Since the precise roles of GM/GGM and AGX are not clear, the elution analysis to evaluate the strength of the interaction between the cell wall were tried. Earlywood (EW) and latewood (LW) were separated in a Japanese cedar. The chemical components of cellulose, hemicellulose including GM/GGM and AGX, and lignin were almost the same in EW and LW. Slight differences in GM/GGM, the side-chain substitution in AGX and the ionic bond characteristics of glucuronic acid side chains were observed. Based on measurements of GM/GGM and AGX adhering to CMFs, there were more hemicelluloses forming strong hydrogen bonds in LW than in EW. The results showed that the highly assembled hemicellulose in LW produced a strong cell wall framework. [ABSTRACT FROM AUTHOR]

The feasibility for the lead-bismuth--cooled accelerator-driven system (ADS) to transmute minor actinides partitioned from high-level radioactive waste is discussed. Since lead-bismuth will cause considerable corrosion and erosion effects at high temperature, the fuel-clad temperature must be kept as low as possible. Moreover, the most critical issue of the ADS design is the engineering viability of the high-power spallation target and the beam window. The thermal-hydraulic and structural analysis was carried out for both the fuel assembly and the beam window. In addition to the analysis in steady state, the transient behaviors were also studied during typical transient and unprotected accidents. The results showed that engineering viability is reasonably achievable in the nominal operation. For the beam trip, which will be the most frequent transient, the number of events to cause the failure of the beam window is estimated as more than 105. For safety aspects of the ADS during unprotected accidents, the estimated results showed that unprotected loss of flow would cause the most significant problem, if the beam operation was kept. Therefore, high reliability of the beam shutdown is required for the ADS safety. [ABSTRACT FROM AUTHOR]