[in Japanese]

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The notched strength prediction of normal glass mat composite and needle punched glass mat composite based on fracture mechanics was carried out in this study. The prediction constitutes of three parts including establishing the relation between characteristic distance and notch strength ratio (a ratio of notch strength to unnotched strength), modulus calculation in thickness direction and fracture toughness measurement. The characteristic distance was determined by point stress criterion and calculated from finite element analysis. After contrastive analysis from a mass of tensile results on notched specimens with an open hole, a relation between characteristic distance and notch sensitivity was established. Modulus calculation was calculated according to the classic theory of "Rule of Mixtures" and "Reuss Model". After that, the results of modulus calculation together with fracture toughness results were employed to establish the relation between notch strength and characteristic distance according to elastic fracture mechanics. The characteristic distance was used in this part as a parameter of a crack. Finally, from the two equations between notch strength and characteristic distance, the notched strength of composite with an open hole can be predicted. The predicting results were compared and analyzed with experiment results.

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[in Japanese]

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A ternary hydride, the face-centered cubic (FCC) type Mg7TiH16, synthesized under 8 GPa hydrogen pressure (HP) exhibited a reversible hydrogenation and dehydrogenation property around 600K on the differential scanning calorimeter (DSC) measurements. The FCC phase was decomposed during hydrogen releasing and restoring cycles. After the hydrogen restored process, the XRD pattern consisted of MgH2, TiH2 and Mg peaks. Meanwhile, a mechanically-alloyed (MA) 7MgH2+TiH2 sample exhibited similar hydrogen storage properties to the HP sample. Based on a structural analysis using the synchrotron XRD data, it was shown that the phase abundance for the HP sample is equivalent to the one for the MA sample.

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The sub-critical water extraction of green tea (Camellia sinensis), composing of free amino acid, was investigated to produce a glutarimide derivative, (S)-3-amino-1-ethylglutarimide (1) along with a known compound, pyroglutamic acid. The structure of 1 was decided on the basis of spectroscopic evidence, including NMR (1H, 13C, DEPT, HSQC and HMBC) and FAB-MS studies. The taste assessment of 1 showed higher umami (good-tasting), bitterness, and astringency than those of the theanine standard. A large quantity preparation of 1 was achieved by sub-critical water extraction of aq. theanine at 180 C and 3 min reaction time. The first isolation of 1 from the plant sourse is described.

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[in Japanese]

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[in Japanese]

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This study aims to consider the possibility of Japan's financial collapse. We surveyed a group of people's thought about governmental finance, and compared their thought. The subjects of our survey are ordinary people and those who have expert knowledge about finance. As a result, the expert people have greatly different opinion about financial policy from those not dealing at a market. It is suggested that the stories of a sacrifice of the governmental bonds or financial collapse were based on the certain people's judgments who cannot analyze market trends in a rational way.

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Kyo-wall is the earthen wall composed of clay containing sand and plant fiber, which is manually kneaded and plastered with the trowels to form there layers inducing the natural and aesthetic surface appearance. Kyo-wall is the traditional technology produced for the compact room to hold Japanese tea ceremony created by Sen-no Rikyu in 16th century and have been succeeded to Kyo-machiya house up to now. The top surface is smoothly covered with clay causing minute aesthetic appearance and the color which is ocher initially becomes to have the dark spots called "Sabi" gradually a few months or a few years later. Sabi has been appreciated as tasteful rust phenomenon of the aged Kyoto wall. However the mechanism of Sabi phenomenon and their control factors have not been understood and have been believed as iron rust caused by air oxidation until now. In this study we have applied the low incident angle X-ray fluorescent mapping technique to get the mineral elements distributions of the top surface of Kyo-wall with Sabi dark spots and Si, Al, Fe, K, Ca, S, Ti, Mn are detected as more than 0.1wt% content. And we have found that only Mn density pattern fits the Sabi spots distribution and Fe density have no connection with the Sabi spots distribution, It is kown that Sabi occurs not on the shaded surface from the wind but on the open surface in the wind and can be seen also in the process of roof tile Kyo-kawara or porcelain Kutaniyaki surface containing clay. Mn ion in the interface water layer of the clay structure seems to bleed out to the surface due to asymmetric turbulent wind flow and to be oxidized by the air. This newly found secret hidden in the traditional technology will be applied as the future technology.

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All industrial products are destined to be museum someday. This means that industrial products are cultural property. When a cultural property is lost, society as a whole is damaged. However, if cultural properties take money and space to preserve, the owner as well. When encountering such a dilemma, law and government can help solve the problem. The Yamagata University Faculty of Engineering was established in 1910. The University owns the main building of the Yonezawa Higher Technical School, which is an important cultural property. Many industrial products, which have completed their mission in life, were on display in the building before the 2011 Tohoku Earthquake and Tsunami. The school building was planned to be renovated in order to overcome the effect of the earthquake. However, Yamagata University ran in to big problem, with the management of the exhibits in the school building. Therefore, we built a database system by utilizing information technology, and this database grew over time. In addition, students worked on conservation activities for their own learning experience. As a result we could finish the creation of the management records and the database of exhibits in a short period of time.

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The purpose of this study was to clarify whether plasma concentrations of GH and lactate (La) are concurrently elevated by resistance training under 15.4 % of hypoxic conditions. Six athletes (age, 21.6 ｱ 1.0 y; height, 175.6 ｱ 5.6 cm; weight, 70.4 ｱ 16.3 kg; means ｱ SD) provided written, informed consent to participate in this study. Seated participants (n = 6) performed 3 sets of 10 repetitions each of bilateral knee extensions at an intensity of 60 % 1Repetition Maximum (RM) at 2 min intervals using an isotonic leg extension machine under normoxic and hypoxic conditions. Plasma concentrations of growth hormone (GH) lactate (La) were measured before and after the training. Concentrations of GH significantly increased at 0 min before and 0 min after exercise under hypoxic conditions (p < 0.05 Wilcoxon signed rank test). The concentration of La tended to be higher after exercise under hypoxic, than normoxic conditions but the difference was not significant. The overall rating of perceived exertion (RPE) did not significantly differ between normoxic and hypoxic conditions. Resistance training under 15.4 % hypoxic conditions have stimulated the secretion of GH than normoxic conditions.

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This paper is about the development of a system that purifies contaminated water with micro-bubbles for solutions of water pollutions such as industrial waste water, rivers, lakes, dams, ground water and ocean. The system is able to generate micro-bubbles from contaminated water by a micro-bubble generator. This micro-bubble generator injects micro-bubbles into contaminated water in a contaminated tank and the micro-bubbles separate the pollutants from clean water in a surface tank. For other systems, it is impossible to generate micro-bubbles into contaminated water directly, the inflow must be separate. However, the system introduced in this paper simplifies the process and makes direct injection possible.

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[in Japanese]

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