182 research outputs found

    Material damage in TBCs by a synthetic CMAS and the non-destructive detection:-An exploration via a single crystal YSZ-

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    More recently a new type of damage has been pronounced in thermal barrier coatings (TBCs) by calcium-magnesium-alumino-silicates (CMAS) from ingestion of siliceous minerals under certain operating conditions, based on synthetic material in Table 1. In order to understand material aspect of CMAS damage, a study on material interaction between a synthetic CMAS and a single crystal yttria-stabilized zirconia (YSZ) was studied in this work. Here, the effect of crystallographic orientation on the interaction was also investigated. The experimental works clearly showed that the material interaction between the CMAS and YSZ was significant, resulting in the change in microstructural morphology(Fig. 1(a)). The extent of interaction depended on the crystallographic factor of the YSZ (Fig. 1(b)). The CMAS damage developed depending on the crystallographic plane of YSZ; it was the lowest onthe {111} plane.This is a noteworthy finding tomitigate the CMAS damagein EB-PVD top coat. The change in physical properties was also found to be pronounced at the CMAS damaged area. Based on these findings the non-destructive detection was also tried for engineering applications. Please click Additional Files below to see the full abstract

    Delamination of ceramic top coat accelerated by CMAS in an EB-PVD thermal barrier coating specimen

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    Application of thermal barrier coatings (TBCs) which provides thermal insulation to the underlying Nickel-based superalloy substrate has been key technologies in advanced gas turbines. More recently, it has been recognized that the TBCs can be damaged by calcium–magnesium–alumino-silicates (CMAS) resulting from siliceous minerals (dust, sand, ash) containing the intake air and from unclean fuels such as a syngas and biomass gas. In this work basic mechanisms and mechanics as well as the kinetics, were explored, via a model CMAS, by specifying a TBC specimen which consisted of a Ni-base superalloy, MCrAlY bond coat and YSZ top coat fabricated by electron beam physical vapor deposition (EB-PVD) process. It was demonstrated that the penetration and the resultant phase transformation of the YSZ with the CMAS were basic mechanisms(Fig.1(a)). It was a particular finding that the thickness of thermal grown oxide was significantly accelerated by CMAS at the top/bond coat interface, resulting in a predominant delamination of top coat(Fig.1(b)). The behavior was discussed, in comparison with that in the TBC specimen fabricated by an air plasma spraying process(Fig.1(c)). Please click Additional Files below to see the full abstract

    Material damage in TBCs by a synthetic CMAS and the non-destructive detection:-An exploration via a single crystal YSZ-

    Get PDF
    More recently a new type of damage has been pronounced in thermal barrier coatings (TBCs) by calcium-magnesium-alumino-silicates (CMAS) from ingestion of siliceous minerals under certain operating conditions, based on synthetic material in Table 1. In order to understand material aspect of CMAS damage, a study on material interaction between a synthetic CMAS and a single crystal yttria-stabilized zirconia (YSZ) was studied in this work. Here, the effect of crystallographic orientation on the interaction was also investigated. The experimental works clearly showed that the material interaction between the CMAS and YSZ was significant, resulting in the change in microstructural morphology(Fig. 1(a)). The extent of interaction depended on the crystallographic factor of the YSZ (Fig. 1(b)). The CMAS damage developed depending on the crystallographic plane of YSZ; it was the lowest onthe {111} plane.This is a noteworthy finding tomitigate the CMAS damagein EB-PVD top coat. The change in physical properties was also found to be pronounced at the CMAS damaged area. Based on these findings the non-destructive detection was also tried for engineering applications. Please click Additional Files below to see the full abstract

    Study on the Teaching Strategy of an Elementary School and Improving the Program for Training Students to be Teachers of University (1) : In the Case of Japanese Language, Arithmetic and Science

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     本研究は,教科内容構成の考え方に基づいて小学校の授業づくりのあり方を検討するとともに,それをふまえることで大学の教員養成プログラムの授業が具体的にどのように改善されるかを明らかにしようとしたものである。教科内容構成とは,教員養成において従来から課題とされてきた教科の内容に関わる知識・技能と教科の指導法に関わる知識・技能の分離という問題を克服するために提案されたものである。教科内容構成は,教科の内容と指導法に関わる知識・技能を統合し,それらを応用して,教師が自ら「どのような内容をどのように教えるべきか」を考え,授業づくりに取り組むことができるようになるための考え方を示すものであり,本研究では教員養成プログラムにおける具体的な授業プランを提示してそれを明らかにしていく。本稿では,特に,小学校の国語科,算数科,理科を事例として論じていくことにしたい

    Study on the Teaching Strategy of an Junior High School and Improving the Program for Training Students to be teachers of University (1) : In the Case of Japanese Language, Arithmetic, Science and Social Studies

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     本研究は,教科内容構成の考え方に基づいて中学校の授業づくりのあり方を検討するとともに,それをふまえることで大学の教員養成プログラムの授業が具体的にどのように改善されるかを明らかにしようとしたものである。教科内容構成とは,教員養成において従来から課題とされてきた教科の内容に関わる知識・技能と教科の指導法に関わる知識・技能の分離という問題を克服するために提案されたものである。教科内容構成は,教科の内容と指導法に関わる知識・技能を統合し,それらを応用して,教師が自ら「どのような内容をどのように教えるべきか」を考え,授業づくりに取り組むことができるようになるための考え方を示すものであり,本研究では教員養成プログラムにおける具体的な授業プランを提示してそれを明らかにしていく。本稿では,特に,中学校の国語科,数学科,理科,社会科を事例として論じていくことにしたい

    A Study on “Subject Contents Organization (SCO)” for Teacher Training Program in the Faculty of Education, Okayama University : Practice and Assessment of SCO in Elementary School and Junior High School Teacher Training Curriculum

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     岡山大学教育学部・教師教育開発センターは,平成23 ~ 27年度「教員の資質向上に寄与する『大学と学校・教育委員会の協働』の実現−学校教育改善との連動で教員養成教育を進化させる−(先進的教員養成プロジェクト)」に取り組んだ。その中の教科構成学開発事業では,本学部で独自に構築・実施しているコア・カリキュラムの中での教科内容構成のあり方について,2つのプロセスから研究を行った。本稿では,平成26年度に学部教育全体で取り組んだ「教科内容構成要素に関するシラバス記述」と,部会員が平成26・27年度に授業を実践した小・中学校の教職および教科に関する科目(数学・理科・家庭科・国語科)の受講生に対して実施した「教科内容構成力」に関するアンケート調査の分析から,本学部の教科内容構成研究の特徴と課題について検討した

    Physical inactivity is associated with decreased growth differentiation factor 11 in chronic obstructive pulmonary disease

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    Rie Tanaka,1 Hisatoshi Sugiura,1 Mitsuhiro Yamada,1 Tomohiro Ichikawa,1 Akira Koarai,1 Naoya Fujino,1 Satoru Yanagisawa,1 Katsuhiro Onodera,1 Tadahisa Numakura,1 Kei Sato,1 Yorihiko Kyogoku,1 Hirohito Sano,1 Shun Yamanaka,1 Tatsuma Okazaki,1 Tsutomu Tamada,1 Motohiko Miura,2 Tsuneyuki Takahashi,3 Masakazu Ichinose1 1Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, Aoba-ku, Sendai, Japan; 2Department of Respiratory Medicine, Tohoku Rosai Hospital, Aoba-ku, Sendai, Japan; 3Department of Internal Medicine, Tohoku Medical and Pharmaceutical University Wakabayashi Hospital, Wakabayashi-ku, Sendai, Japan Background: Growth differentiation factor 11 (GDF11) is reported to possess anti-aging and rejuvenating effects, including muscle regeneration and to be highly expressed in skeletal muscle. Recently, we demonstrated that the levels of plasma GDF11 were decreased in COPD. However, the effect of decreased circulating GDF11 in the pathophysiology of COPD remains unknown. The aim of this study is to investigate the association between the plasma GDF11 levels and various clinical parameters in patients with COPD. Patients and methods: Eighteen ex-smokers as control subjects and 70 COPD patients participated in the current study. We measured the levels of plasma GDF11 using immunoblotting, lung function, physical activity using a triaxial accelerometer, quadriceps strength, exercise capacity, and systemic inflammatory markers. We investigated the association between the levels of plasma GDF11 and these clinical parameters. Results: The levels of plasma GDF11 in the COPD patients had significant positive correlations with the data of lung function. Furthermore, the levels of plasma GDF11 were significantly correlated with the physical activity, quadriceps strength, and exercise capacity. Moreover, the levels of plasma GDF11 were significantly correlated with the data of inflammatory markers. Although various factors were related to GDF11, the multiple regression analysis showed that physical activity was significantly associated with the levels of plasma GDF11. Conclusion: Physical inactivity was significantly related to the decreased GDF11 levels in COPD, which might be useful for understanding the pathogenesis of COPD. Clarifying the relationships between the physical inactivity and GDF11 may reveal a potentially attractive therapeutic approach in COPD via increasing the plasma levels of GDF11. Keywords: physical activity, muscle strength, rejuvenating factor, COP

    Prenatal diagnosis of severe mitochondrial diseases caused by nuclear gene defects: a study in Japan

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    Prenatal diagnoses of mitochondrial diseases caused by defects in nuclear DNA (nDNA) or mitochondrial DNA have been reported in several countries except for Japan. The present study aimed to clarify the status of prenatal genetic diagnosis of mitochondrial diseases caused by nDNA defects in Japan. A comprehensive genomic analysis was performed to diagnose more than 400 patients, of which, 13 families (16 cases) had requested prenatal diagnoses. Eight cases diagnosed with wild type homozygous or heterozygous variants same as either of the heterozygous parents continued the pregnancy and delivered healthy babies. Another eight cases were diagnosed with homozygous, compound heterozygous, or hemizygous variants same as the proband. Of these, seven families chose to terminate the pregnancy, while one decided to continue the pregnancy. Neonatal- or infantile-onset mitochondrial diseases show severe phenotypes and lead to lethality. Therefore, such diseases could be candidates for prenatal diagnosis with careful genetic counseling, and prenatal testing could be a viable option for families
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