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In this study, for the understandings of Cesium (Cs) adsorption behavior on structure materials in severe accidents in a light water nuclear reactor, the chemical state of Cs and its distribution on the surface of SUS304 stainless steel (SS) with different Si concentrations was investigated by hard X-ray photoelectron spectroscopy (HAXPES) and scanning electron microscope/energy dispersive X-ray spectroscopy (SEM/EDX). As a result, it was found that Cs is selectively adsorbed at the site where Si distributes with a high concentration. CsFeSiO 4 is the dominant Cs products in case of low Si content, while Cs 2 Si 2 O 5 and Cs 2 Si 4 O 9 are formed in addition to CsFeSiO 4 in case of high Si content. The chemical forms of the Cs compounds produced in the adsorption process on the SS surface have a close correlation with the concentration and chemical states of Si originally included in SS. [ABSTRACT FROM AUTHOR]

Deformation behavior and formability of AZ91 magnesium alloy containing a small volume of liquid were investigated by compressive tests between 703 and 803 K and by forging tests between 753 and 803 K. Partial melting occurred initially at 743 K, however, the deformation mechanism changed at 773 K. Thus, the presence of liquid does not always lead to a change in deformation mechanism. The forging tests showed that excellent formability was attained at more than 773 K. It was suggested that the liquid serves to relax the stress concentrations caused by piles of dislocations, resulting in acceleration in flow of the solid. Also, grain refinement due to dynamic recrystallization was attained. Thus, both excellent formability and grain refinement were simultaneously attained by compressive deformation in a semi-solid state containing a small volume of liquid. [Copyright &y& Elsevier]

A porous 7075 Al alloy was fabricated by bubble expansion in a semi-solid state. After processing at 903 K for 72 h in semi-solid state, pores were formed relatively uniformly and a high porosity of 75% was attained. [Copyright &y& Elsevier]

Dentin matrix protein 1 (DMP1) is one of the acidic phosphorylated extracellular matrix proteins called the SIBLING (small integrin-binding ligand, N-linked glycoproteins) family. Recent studies showed that DMP1 is expressed in the mineralized tissues and suggested that DMP1 is involved in the mineralization. We investigated the precise localization of DMP1 messenger RNA (mRNA) and protein during fracture healing. In situ hybridization demonstrated that DMP1 mRNA was strongly expressed in preosteocytes and osteocytes in the bony callus during intramembranous and endochondral ossification while DMP1 mRNA was not detected in osteoblasts and chondrocytes. During endochondral ossification, however, a low number of DMP1-expressing cells were identified in the cluster of hypertrophic chondrocytes. However, these DMP1-expressing cells were not hypertrophic and were likely to be osteoblast-lineage cells, which were embedded in the matrix of bone or cartilage, because type I collagen-expressing cells and invasion of capillary vessels were observed in the same area. Northern blot, in situ hybridization, and immunohistochemical analyses showed that DMP1 mRNA and protein expressions were increased until day 14 postfracture, when bony callus was formed, and then declined to a lower level during remodeling of the bony callus. Therefore, DMP1 is likely to play an important role in the mineralization of the bony callus. [Copyright &y& Elsevier]