Helium retention behavior of 316L stainless steel (316L SS) used for the first wall of the large helical device (LHD) was investigated by using an ECR plasma/ion apparatus and thermal desorption ...spectroscopy. Samples of 316L SS were irradiated by helium ions with different energy. After helium ion irradiation with 100s eV energy, the desorption temperature of the retained helium was below 800K. As increasing ion energy, the fraction of helium desorbed temperatures >800K gradually increased. The retained amount of helium saturated for ion fluences above 1.0×1017He/cm2. The retained amount of He was similar to that observed in other plasma facing materials. For irradiation fluences >1.0×1017He/cm2, blister formation was observed. The present results are consistent with the desorption behavior of 316L SS samples exposed to LHD plasmas.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Lithium titanate (Li2TiO3) pebbles were irradiated with deuterium ions with energy of 1.7keV and then exposed to helium or helium–hydrogen mixed gas at various temperatures, in order to evaluate the ...effects of gas exposure on deuterium removal from the pebbles. The amounts of residual deuterium in the pebbles were measured by thermal desorption spectroscopy. The mixing of hydrogen gas into helium gas enhanced the removal amount of deuterium. In other words, the amount of residual deuterium after the helium–hydrogen mixed gas exposure at lower temperature was lower than that after the helium gas exposure. In addition, we also evaluated the pebbles exposed to the helium gas with different hydrogen mixture ratio from 0% to 1%, at 573K. Although the amount of residual deuterium in the pebbles after the exposure decreased with increasing the hydrogen mixture ratio, the implanted deuterium partly remained after the exposure. These results suggest that the tritium inventory may occur at low temperature region in the blanket during the operation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The removal of deuterium retained in boron, titanium, and titanium oxide films by neon glow discharge was investigated. The films were exposed to deuterium glow plasma to retain the deuterium and ...subsequently exposed to neon glow plasma. The temperature of the exposures was room temperature. The residual deuterium was estimated by thermal desorption spectroscopy. The removal ratio of deuterium by neon glow discharge largely depended on the material. Namely, the ratios for boron, titanium, or titanium oxide were 14%, 2%, or 40%, respectively. The ratios for the boron and the titanium oxide roughly agreed with the estimation from SRIM code calculations, while the ratio for the titanium did not agree with the estimation. These results suggest that the reduction of the deuterium retention is owing to the etching and the ion impact desorption of neon ions in the cases of boron and titanium oxide, and the prompt re-trapping of deuterium by titanium atoms might occur in the case of titanium. The comparison between titanium and titanium oxide clearly shows that the removal effect by glow discharge largely depended on the surface conditions, such as oxygen impurity.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
The removal of deuterium retained in boron, titanium, and titanium oxide films by neon glow discharge was investigated. The films were exposed to deuterium glow plasma to retain the deuterium and ...subsequently exposed to neon glow plasma. The temperature of the exposures was room temperature. The residual deuterium was estimated by thermal desorption spectroscopy. The removal ratio of deuterium by neon glow discharge largely depended on the material. Namely, the ratios for boron, titanium, or titanium oxide were 14%, 2%, or 40%, respectively. The ratios for the boron and the titanium oxide roughly agreed with the estimation from SRIM code calculations, while the ratio for the titanium did not agree with the estimation. These results suggest that the reduction of the deuterium retention is owing to the etching and the ion impact desorption of neon ions in the cases of boron and titanium oxide, and the prompt re-trapping of deuterium by titanium atoms might occur in the case of titanium. The comparison between titanium and titanium oxide clearly shows that the removal effect by glow discharge largely depended on the surface conditions, such as oxygen impurity.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
ABSTRACT
Background. Extracellular urease proteins located on the surface of Helicobacter pylori are gastric mucin‐targeted adhesins, which play an important role in infection and colonization to ...the host. In this study we have determined the inhibitory activity of a variety of melanoidins, protein‐derived advanced Maillard reaction products, ubiquitously found in heat‐treated foods, on urease‐gastric mucin adhesion. In addition, we have determined the anticolonization effect of melanoidin I, prepared by the Maillard reaction between casein and lactose, in an animal model and in human subjects infected with this bacterium.
Methods. The inhibitory activity of each compound was determined by a competitive binding assay of labeled gastric mucin to plate‐immobilized urease. Melanoidin I was used in an in vivo trial using euthymic hairless mice as an infection model. Melanoidin I was consumed for 8 weeks by subjects infected with H. pylori. The 13C urease breath test and H. pylori‐specific antigen in the stool (HpSA) test were performed on subjects at week 0 and week 8.
Results. A variety of food protein‐derived melanoidins strongly inhibited urease‐gastric mucin adhesion in the concentration range of 10 µg/ml to 100 µg/ml. In particular, melanoidin I significantly (p < .05) suppressed colonization of H. pylori in mice when given for 10 weeks via the diets. Eight weeks daily intake of 3 g melanoidin I significantly (p < .05) decreased the optical density of HpSA in subjects.
Conclusion. Foods containing protein‐derived melanoidins may be an alternative to antibiotic‐based therapy to prevent H. pylori that combines safety, ease of administration and efficacy.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
48.
Wall Conditioning in LHD Masuzaki, S.; Ashikawa, N.; Nishimura, K. ...
Fusion science and technology,
08/2010, Volume:
58, Issue:
1
Journal Article
Peer reviewed
Wall conditioning in the Large Helical Device (LHD) has been conducted successively since the first experimental campaign in 1998. The effects of wall conditioning on the vacuum condition, the plasma ...performance, and the surface modification of the plasma-facing components have been analyzed by both macroscopic and microscopic observations such as residual gas analysis and transmission electron microscope observation, respectively. The main tools for the conditioning are mild baking (95°C); glow discharges with hydrogen, helium, and neon; and wall coating with titanium and boron. Though the baking temperature is lower than in other fusion devices, it reduces impurity gases well just after the start of vacuum pumping, and it reduces retained hydrogen in plasma-facing components during the experimental campaign. Helium glow discharge was revealed to cause heavy damage on the surfaces of metallic components and the contamination of the hydrogen discharges with helium released from wall. Neon glow discharge has been conducted since it causes much less damage and hastens the conditioning of the wall. Boronization is very effective to reduce oxygen impurity in plasma, and the effects last for the whole experimental campaign in LHD.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Strobilurus ohshimae is an edible mushroom, and it specifically forms its fruiting bodies on buried sugi (Cryptomeria japonica) twigs. In this research, we studied lignindegrading activity of S. ...ohshimae. We isolated 18 strains of S. ohshimae from various regions of Japan, and determined their lignin degradation rates on sugi wood meal medium. All the strains of S. ohshimae degraded approximately 6%–12% of sugi lignin in 30 days, and these lignin degradation rates were 1.5–3 times higher than those of Trametes versicolor, which is a typical lignin-degrading fungus. Among the three main lignin-degrading enzymes, activity of lignin peroxidase and manganese peroxidase was not observed, while 4340U/g of laccase was produced in 30 days. To investigate the effect of wood species on lignin degradation by S. ohshimae, the lignin degradation rate and laccase productivity on sugi wood meal medium were compared with those on beech (Fagus crenata). In T. versicolor, both lignin degradation rate and laccase productivity were higher on beech than on sugi. Conversely, in S. ohshimae, lignin degradation rate and laccase productivity were higher on sugi than on beech. Therefore, it was suggested that coniferous lignin is not always difficult to degrade for the fungi that inhabit softwood.
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FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UL, UM, UPUK, VKSCE, ZAGLJ
The Standard Specifications for Concrete Structures were revised and published by Japan Society of Civil Engineers in December 2007. The 2007 edition was consisted of 5 parts, “Design”, “Materials ...and Construction”, “Dam Concrete”, “Maintenance” and “Standards for test methods and material quality”. This paper describes main revisions in 4 parts excluding “Standards for test methods and material quality”. Having in mind for making the specifications convenient to practicing engineers, the revision was carried out to maintain the least requirements for introducing the up-to-date developments in concrete technology, to optimize the current performance-based specifications and to synchronize all constituent parts so as to create a perfect connection between different parts. It is believed that this revision is a fine integration between the rationality based on performance verification concept and the practical applicability.
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