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Lessons from International Students’ Reaction to the 2011 Great East Japan Earthquake:The Case of the School of Engineering at tohoku university

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International Journal of Disaster Risk Science 2013年第3期4卷 137-149页

作者： Oscar A.Gómez Graduate School of Global Studies Doshisha UniversityKyoto 602-0898Japan

The objective of this study is to document the reaction of international students to the 11 March 2011 emergency in order to inform and improve disaster management strategies, both public and institutional. The study is based mainly on a questionnaire survey carried out in August 2011 and follow-up interviews with students and other stakeholders. It describes the background of tohoku university’s School of Engineering and covers six different stages in the evolution of the emergency:(1) immediate response;(2) taking shelter in Sendai;(3) life in the city during the aftermath;(4) sheltering outside Sendai;(5) coming back;plus(6) an overview of the experience. Major findings include: the process of evacuation and safety confirmation was successful, yet the subsequent phases(2 and 3) went on mostly unmanaged;students relied mostly on secondary sources of information to make decisions, mainly family and friends of the same nationality, most of whom probably were not better informed than the students themselves. Based on the findings, suggestions for future disaster planning are advanced, as well as a discussion on the challenges of information provision during crisis.

关键词： disaster mostly Great

Aging-induced memory loss due to decreased N1-acetyl-5-methoxykynuramine,a melatonin metabolite,in the hippocampus:a potential prophylactic agent for dementia

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Neural Regeneration Research 2025年第6期20卷 1705-1706页

作者： Kazuki Watanabe Atsuhiko Hattori Department of Immunobiology Institute of Development Aging and CancerTohoku UniversitySendaiMiyagiJapan Department of Sport and Wellness College of Sport and WellnessRikkyo UniversityNiizaSaitamaJapan

Melatonin(N-acetyl-5-methoxytryptamine)is known as the hormone of darkness because it is synthesized at night and involved in regulating the circadian *** hormone is primarily synthesized by the vertebrate pineal gland,but is ubiquitous among invertebrates,unicellular organisms,plants,and even cyanobacteria(Hattori and Suzuki,2024).Melatonin is well-conserved evolutionarily and possesses several physiological functions,such as immune response,bone and glucose metabolism,and memory formation besides regulating the circadian rhythm.

关键词： metabolism primarily agent

Numerical Modelling and Simulation of Chemical Reactions in a Nano-Pulse Discharged Bubble for Water Treatment

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Plasma Science and Technology 2016年第9期18卷 924-932页

作者：何雨辰 Satoshi UEHARA Hidemasa TAKANA Hideya NISHIYAMA Graduate school of Engineering Tohoku University Institute of Fluid Science Tohoku University

A zero-dimensional model to simulate a nano-pulse-discharged bubble in water was developed. The model consists of gas and liquid phases corresponding to the inside and outside of the bubble, respectively. The diffusions of chemical species from the gas to the liquid phase through the bubble interface was also investigated. The initial gas is Ar, but includes a little H20 and 02 in the bubble. The time evolution of the OH concentration in the liquid phase was mainly investigated as an important species for water treatment. It was shown that OH was generated in the bubble and then diffused into the liquid. With the application of a continuous nano-pulse discharge, more OH radicals were generated as the frequency increased at a low voltage for a given power consumption.

关键词： chemical reaction model water purification bubble discharge diffusion

High Resolution Clinometers for Measurement of Roll Error Motion of a Precision Linear Slide

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 8-16页

作者： Yuki Shimizu Satoshi Kataoka Wei Gao Department of Finemechanics Tohoku University

This paper proposes a new method for measurement of the roll error motion of a slide table in a precision linear slide. The proposed method utilizes a pair of clinometers in the production process of a precision linear slide, where the roll error motion measurement will be carried out repeatedly to confirm whether the surface form errors of slide guideways in the linear slide are su ciently corrected by hand scraping process. In the proposed method, one of the clinometers is mounted on the slide table, while the other is placed on a vibration isolation table, on which the precision linear slide is mounted, so that influences of external disturbances can be cancelled. An experimental setup is built on a vibration isolation table, and some experiments are carried out to verify the feasibility of the proposed method.

关键词： Linear slide Clinometer Rotational error motion measurement

A technique utilizing chemical reagents for direct measurement of temperature at a local area and its engineering applications

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Acta Mechanica Sinica 2009年第2期25卷 149-160页

作者： M.Saka T.Hasegawa Department of Nanomechanics Tohoku University

Temperature is one of the physical quantifies through which quantitative evaluation of the safety and reliability of industrial products can be achieved, and this has been used widely in practice. Under any environmental condifion, regardless of the size of the object to be inspected, accurate and reliable measurement of temperature is of great practical importance. This review article presents a simple and direct method of temperature measurement, that can be applied to the local areas with difficulty in measuring the temperature by using normal thermometers. In the present article, two different application examples are demonstrated. One addresses the study of the electromigration of solders which are used as bonding metals in electronic devices （micro-structures）. The application of the method to the shaft of a motor used in heavy industrial fields is explained as the second.

关键词： Temperature measurement Chemicalreagents Melting point Temperature distribution

Activity coefficients of NiO and CoO in CaO–Al_2O_3–SiO_2 slag and their application to the recycling of Ni–Co–Fe-based end-of-life superalloys via remelting

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International Journal of Minerals,Metallurgy and Materials 2017年第1期24卷 25-36页

作者： Xin Lu Takahiro Miki Tetsuya Nagasaka Graduate School of Engineering Tohoku University

To design optimal pyrometallurgical processes for nickel and cobalt recycling, and more particularly for the end-of-life process of Ni-Co-Fe-based end-of-life（EoL） superalloys, knowledge of their activity coefficients in slags is essential. In this study, the activity coefficients of NiO and CoO in CaO-Al_2O_3-SiO_2 slag, a candidate slag used for the EoL superalloy remelting process, were measured using gas/slag/metal equilibrium experiments. These activity coefficients were then used to consider the recycling efficiency of nickel and cobalt by remelting EoL superalloys using CaO-Al_2O_3-SiO_2 slag. The activity coefficients of NiO and CoO in CaO-Al_2O_3-SiO_2 slag both show a positive deviation from Raoult＇s law, with values that vary from 1 to 5 depending on the change in basicity. The activity coefficients of NiO and CoO peak in the slag with a composition near B =（%CaO）/（%SiO_2） = 1, where B is the basicity. We observed that controlling the slag composition at approximately B = 1 effectively reduces the cobalt and nickel oxidation losses and promotes the oxidation removal of iron during the remelting process of EoL superalloys.

关键词： recycling nickel cobalt end-of-life superalloys activity coefficients remelting slag

Synthesis,structure and mechanical properties of Zr-Cu-based bulk metallic glass composites

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 208-213页

作者： Akihisa Inoue Institute for Materials Research tohoku university

The unusual glass-forming ability（GFA） of the Zr48Cu36Ag8Al8 alloy and the high ductility of the Zr48Cu36Ag8Al8 metallic glass-matrix composites containing Ta powder were *** bulk metallic glass rod with a diameter of 25 mm was successfully synthesized using copper mold casting for the Zr48Cu36Ag8Al8 *** GFA of this alloy was found to be related to a large supercooled liquid region and a quaternary eutectic point with low melting *** bulk metallic glass matrix composites were prepared by introducing extra Ta particles into the Zr48Cu36Ag8Al8 *** composites consist of Ta particles homogenously distributed in the Zr48Cu36Ag8Al8 metallic glass *** optimum content of Ta powder is 10at%for the composite with the highest plasticity,which shows a plastic strain of 31%.

关键词： bulk metallic glass composites glass forming ability Zr-Cu-based alloy plastic strain

The role of water in Earth's mantle

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National Science Review 2020年第1期7卷 224-232页

作者： Eiji Ohtani Graduate School of Science Tohoku University

Geophysical observations suggest that the transition zone is wet locally. Continental and oceanic sediment components together with the basaltic and peridotitic components might be transported and accumulated in the transition zone. Low-velocity anomalies at the upper mantle–transition zone boundary might be caused by the existence of dense hydrous magmas. Water can be carried farther into the lower mantle by the slabs. The anomalous Q and shear wave regions locating at the uppermost part of the lower mantle could be caused by the existence of fluid or wet magmas in this region because of the water-solubility contrast between the minerals in the transition zone and those in the lower mantle. δ-H solid solution AlO2H–MgSiO4H2carries water into the lower mantle. Hydrogen-bond symmetrization exists in high-pressure hydrous phases and thus they are stable at the high pressures of the lower mantle. Thus, theδ-H solid solution in subducting slabs carries water farther into the bottom of the lower mantle. Pyrite FeO2Hxis formed due to a reaction between the core and hydrated slabs. This phase could be a candidate for the anomalous regions at the core–mantle boundary.

关键词： water hydrous phase subducting slab transition zone lower mantle hydrogen-bond symmetrization core–mantle boundary

Gustav Senn(1875–1945): The pioneer of chloroplast movement research

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Journal of Integrative Plant Biology 2015年第1期57卷 4-13页

作者： Hironao Kataoka Botanical Gardens Tohoku University

Gustav Senn analyzed for the first time light- induced movement and arrangement of chloroplasts. Using many plant species he performed physiological analyses of chloroplast migration in response to external stimuli, with emphasis on light. He determined light paths within a cell by measuring refractive indices and optical thickness of cellular compartments and confirmed that chloroplasts migrate towards the region where the light intensity is optimum. After 6 to 7 years＇ concentrated study, Senn published the famous monograph ＂Die Gestalts- und Lageveranderung der Pflanzen- Chromatophoren＂（The Changes in Shape and Position of Plant Chloroplasts） in 1908. This book has stimulated many plantphysiologists and photobiologists, because Senn not only thoroughly classified and defined various types of light-induced chloroplast migration but also already described possible interaction of different photoreceptor systems in Nlougeotia more than 50 years before the discovery of phytochrome. This book also contains still useful experimental hints and over- looked findings on the interaction between light and other factors, such as temperature, water content, and nourishment. After publishing this book, Senn retreated from the study of chloroplasts and became a researcher of the Greek philoso- pher, Theophrastus. In this review, I introduce his biographical background and then summarize some of his key research accomplishment.

关键词： Chloroplast Custav Senn Mougeotia photomovement Vaucheria