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5. Changes in Cerebral Hemodynamics During Systemic Pulmonary Shunt and Pulmonary Artery Banding in Infants with Congenital Heart Disease

Author

Takeda, Yoshifumi, Yamamoto, Masataka, Hoshino, Koji, Ito, Yoichi M., Kato, Nobuyasu, Wakasa, Satoru, Morimoto, Yuji, Takeda, Yoshifumi, Yamamoto, Masataka, Hoshino, Koji, Ito, Yoichi M., Kato, Nobuyasu, Wakasa, Satoru, and Morimoto, Yuji

Abstract

Palliative surgery is often performed in the treatment of congenital heart disease. Two representative palliative procedures are the systemic pulmonary shunt and pulmonary artery banding. Dramatic changes in cerebral hemodynamics may occur in these operations due to changes in the pulmonary-to-systemic blood flow ratio and systemic oxygenation. However, there seem to be almost no studies evaluating them. Accordingly, we evaluated cerebral perfusion by transcranial Doppler ultrasonography and cerebral oxygenation by near infrared spectroscopy during these procedures. In the post hoc analysis of a previous prospective observational study, cerebral blood flow velocities of the middle cerebral artery measured by transcranial Doppler were compared between the start and end of surgery as were the pulsatility index and resistance index. The cerebral oxygenation values were also compared between the start and end of surgery. Twenty-two infants with systemic pulmonary shunt and 20 infants with pulmonary artery banding were evaluated. There were no significant differences of the flow velocities between the start and end of surgery in either procedure. The pulsatility index significantly increased after pulmonary artery banding, which may compete with the increase in cerebral perfusion due to the increase in systemic blood flow. The cerebral oxygenation decreased in both procedures, possibly due to an increase in body temperature. Arterial oxygen saturation was almost the same before and after both procedures. Contrary to our expectation, the changes in cerebral hemodynamics in the palliative operations were small if the management of physiological indices such as arterial oxygen saturation was properly performed during the procedures.

Published
2023

10. Age Difference of the Relationship Between Cerebral Oxygen Saturation and Physiological Parameters in Pediatric Cardiac Surgery with Cardiopulmonary Bypass : Analysis Using the Random-Effects Model

Author

Yamamoto, Masataka, Toki, Takayuki, Kubo, Yasunori, Hoshino, Koji, 1000000250457, Morimoto, Yuji, Yamamoto, Masataka, Toki, Takayuki, Kubo, Yasunori, Hoshino, Koji, 1000000250457, and Morimoto, Yuji

Abstract

Recently, monitoring of cerebral oxygen saturation (ScO2) has become widespread in pediatric cardiac surgery. Our previous study reported that mean blood pressure (mBP) was the major contributor to ScO2 throughout cardiac surgery with cardiopulmonary bypass (CPB) in children weighing under 10 kg. We speculated that this result might be attributable to incomplete cerebral autoregulation in such young children. Accordingly, our hypothesis is that the relationship between ScO2 and the physiological parameters may change according to the growth of the children. ScO2 was measured with an INVOS 5100C (Somanetics, Troy, MI). Random-effects analysis was employed with ScO2 as a dependent variable, and seven physiological parameters (mBP, central venous pressure, nasopharyngeal temperature, SaO(2), hematocrit, PaCO2, and pH) were entered as independent covariates. The analysis was performed during the pre-CPB, CPB, and post-CPB periods by dividing the patients into two groups: infants (Infant Group) and children who were more than 1 year old (Child Group). The Infant and Child Groups consisted of 28 and 21 patients. In the random-effects analysis, mBP was the major contributor to ScO2 during CPB in both groups. During the pre-CPB period, the effect of mBP was strongest in the Infant group. However, its effect was second to that of SaO(2) in the Child Group. During the post-CPB period, SaO(2) and mBP still affected ScO2 in the Infant group. However, the dominant contributors were unclear in the Child Group. Cerebral autoregulation may be immature in infants. In addition, it may be impaired during CPB even after 1 year of age.

Published
2022

18. Effects of electronic structures on the excited-state intramolecular proton transfer of 1-hydroxy-2-acetonaphthone and related compounds

Author

Tobita, Seiji, Yamamoto, Masataka, Kurahayashi, Noriko, Tsukagoshi, Rie, Nakamura, Yosuke, and Shizuka, Haruo

Subjects
Protons -- Research, Naphthalene -- Research, Acetone -- Research, Molecular electronics -- Research, Chemicals, plastics and rubber industries
Abstract

Effects of electronic structures on the excited-state intramolecular proton transfer (ESIPT) of 1-hydroxy-2-acetonaphthone (1H2AN) and its related compounds 1-hydroxy-2-naphthaldehyde (1H2NA) and methyl 1-hydroxy-2-naphthoate were studied by means of the laser photolysis method, time-resolved thermal lensing technique, and fluorometry. Findings suggest the occurrence of ESIPT in 1H2AN and 1H2NA to form a long-lived keto-tautomer. Distinct relation properties were attributable to differences in relative stabilities between parent enol and tautomeric keto-forms.

Published
1998

19. Accuracy of Temporo-Spatial and Lower Limb Joint Kinematics Parameters Using OpenPose for Various Gait Patterns With Orthosis.

Author

Yamamoto, Masataka, Shimatani, Koji, Hasegawa, Masaki, Kurita, Yuichi, Ishige, Yuto, and Takemura, Hiroshi

Subjects
ANKLE, KNEE, KINEMATICS, GAIT in humans, MOTION capture (Human mechanics), ANATOMICAL planes
Abstract

A cost-effective gait analysis system without attachments and specialized large environments can provide useful information to determine effective treatment in clinical sites. This study investigates the capability of a single camera-based pose estimation system using OpenPose (OP) to measure the temporo-spatial and joint kinematics parameters during gait with orthosis. Eleven healthy adult males walked under different conditions of speed and foot progression angle (FPA). Temporo-spatial and joint kinematics parameters were measured using a single camera-based system with OP and a three-dimensional motion capture system. The limit of agreement, mean absolute error, absolute agreement (ICC2, 1), and relative consistency (ICC3, 1) between the systems under each condition were assessed for reliability and validity. The results demonstrated that most of the ICC for temporo-spatial parameters and hip and knee kinematics parameters were good to excellent (0.60 - 0.98). Conversely, most of the ICC for ankle kinematics in all conditions were poor to fair (< 0.60). Thus, the gait analysis using OP can be used as a clinical assessment tool for determining the temporo-spatial, hip, and knee sagittal plane angles during gait. [ABSTRACT FROM AUTHOR]

Published
2021
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24. 宇宙往還機開発計画の概要

Author

Yamamoto, Masataka, 山本 昌孝, Yamamoto, Masataka, and 山本 昌孝

Abstract

NAL and NASDA have been engaged in collaborative studies and experiments since the first half of 1980's purposing establishment of HOPE (H-2 Orbiting Plane) system and its main elemental technology. The historical details, outline of experiments, and HOPE project relating to future plan are summarized., NALとNASDAは、将来の多様な宇宙活動の安定的展開に不可欠な宇宙往還輸送システムを確立するため、1980年代前半以来、有翼往還機(HOPE)のシステム技術および主要な要素技術の確立を目的として共同作業を行ってきた。その開発の経緯、実験の概要、HOPE計画と将来構想について概説した。

Published
2015

25. 軌道再突入実験(OREX)概要

Author

Yamamoto, Masataka, Akimoto, Toshio, Yamawaki, Koji, Inaba, Motoyuki, Shimoda, Takayuki, Inoue, Yasutoshi, 山本 昌孝, 秋元 敏男, 山脇 功次, 稲葉 基之, 下田 孝幸, 井上 安敏, Yamamoto, Masataka, Akimoto, Toshio, Yamawaki, Koji, Inaba, Motoyuki, Shimoda, Takayuki, Inoue, Yasutoshi, 山本 昌孝, 秋元 敏男, 山脇 功次, 稲葉 基之, 下田 孝幸, and 井上 安敏

Abstract

The Orbital Re-entry Experiment (OREX) flight experiment is part of the research for the H-2 Orbiting Plane (HOPE). Its purposes are to contribute to HOPE development by accumulating experience in designing and producing a re-entry vehicle and acquiring re-entry data which is difficult to acquire in ground experiments. The OREX vehicle had been launched February 4, 1994 at Tanegashima space center and inserted into orbit by H-2 rocket. Vehicle came turn around over the Tanegashima island. It could get experimental data during re-entry, transmitted data to the grand stations after re-entry successfully, and splashed down in the Central Pacific Ocean. The OREX project was conducted in cooperation with the National Aerospace Laboratory (NAL) and NASDA., 軌道再突入実験(OREX)は、H-2ロケット打上げ型有翼回収機(HOPE)の研究開発の一環として実施する飛行実験の一つであり、軌道からの大気圏再突入に耐える飛行体の設計･製作技術を蓄積するとともに、地上での試験では取得が困難な再突入時の各種データを取得することにより、HOPEの開発に役立てることを目的としている。軌道再突入実験機は1994年2月4日種子島宇宙センターからH-2ロケットにより打ち上げられ、地球を一周した後大気圏に再突入し、この間再突入に関する実験データを取得、送信した後、中部太平洋上に着水した。本実験の開発は、航空宇宙技術研究所(NAL)と宇宙開発事業団(NASDA)との共同研究として進められた。

Published
2015

26. Study of space cryocoolers

Author

Iida, Teruhito, Yamamoto, Masataka, 飯田 光人, 山本 昌孝, Iida, Teruhito, Yamamoto, Masataka, 飯田 光人, and 山本 昌孝

Abstract

NASDA English Translation

Published
2015

27. 極超音速飛行実験(HYFLEX)計画

Author

Shirouzu, Masao, Inoue, Yasutoshi, Takizawa, Minoru, Kai, Takashi, Yamamoto, Yukimitsu, Yamamoto, Masataka, Watanabe, Shigeya, Shimoda, Takayuki, Teraoka, Ken, Suzuki, Yusuke, 白水 正男, 井上 安敏, 滝沢 実, 甲斐 高志, 山本 行光, 山本 昌孝, 渡辺 重哉, 下田 孝幸, 寺岡 謙, 鈴木 裕介, Shirouzu, Masao, Inoue, Yasutoshi, Takizawa, Minoru, Kai, Takashi, Yamamoto, Yukimitsu, Yamamoto, Masataka, Watanabe, Shigeya, Shimoda, Takayuki, Teraoka, Ken, Suzuki, Yusuke, 白水 正男, 井上 安敏, 滝沢 実, 甲斐 高志, 山本 行光, 山本 昌孝, 渡辺 重哉, 下田 孝幸, 寺岡 謙, and 鈴木 裕介

Abstract

A hypersonic flight experiment project of a lifting-body type vehicle named HYFLEX (Hypersonic Flight Experiment) is in progress by the National Aerospace Laboratory and the National Space Development Agency as a part of collaborative activities for the development of HOPE. The vehicle will be separated at a velocity of about 3.9 km/s from the second stage of the J-1 launcher and will acquire flight data during its glide descent. This paper describes the purpose and the outline of the experiment, aerodynamic characteristics, sub-components, and guidance and control of the vehicle, as well as onboard data acquisition, and schedule., 小型の実験機を用いた極超音速飛行実験(HYFLEX)計画がHOPE開発研究の一環として航空宇宙技術研究所と宇宙開発事業団の協力の下で進められている。実験機は2段式のJ-1ロケットにより高度110km,速度約3.9km/sで分離され、滑空飛行中に空力加熱計測、熱防護系評価、誘導制御技術評価などのための飛行データを取得する。本論文は、実験計画の目的、概要、実験機の空力特性、サブシステム、誘導制御則、実験計測および開発計画などについて述べる。

Published
2015

28. On flight data of HYFLEX

Author

Watanabe, Shigeya, Shirouzu, Masao, and Yamamoto, Masataka

Subjects
空力加熱, 数値流体力学, HYFLEX, 電子密度, 大気データセンサ, computational fluid dynamics, H-2ロケット打ち上げ型有翼回収機, gas jet interaction, H 2 orbiting plane, 極超音速飛行実験, air data sensor, thermal protection system, aerodynamic characteristic, 熱防護システム, aerodynamic heating, HOPE, hypersonic lifting flight, 航空機計算空気力学, aircraft computational aerodynamics, 空力特性, ガスジェット相互作用, electron density, CFD, 極超音速揚力飛行, hypersonic flight experiment
Abstract

航空宇宙技術研究所 6-7 JUN. 1996 東京 日本, National Aerospace Laboratory 6-7 JUN. 1996 Tokyo Japan, 日本のHOPE(H-2ロケット打上げ型有翼回収機)の開発のために計画した、HYFLEX(極超音速飛行実験)を1996年2月12日に成功裏に実施した。実験に使用した飛行体は全長4.4mの細長いボディ形状をしており、全備重量は1,073kgである。飛行実験を通して空気力学、熱防護システム、誘導・制御に関する種々の極超音速揚力飛行データを取得した。極超音速航空力学に関連する以下の飛行データ、すなわち空力特性、空力加熱、ADS(大気データセンサ)とRCS(ガスジェット姿勢制御システム)ガスジェット相互作用実験のための圧力測定、および機体周りの電子密度などを簡単に概観した。予測法の有効性を検討するため、飛行データを風洞試験結果およびCFD(数値流体力学)計算に基づく飛行前予測データと比較した。, HYFLEX (Hypersonic Flight Experiment) which was planned for the development of the Japanese unmanned orbiting plane, HOPE (H-2 Orbiting Plane), was successfully conducted on Feb. 12, 1996. The vehicle used in the experiment has a 4.4 m-long slender body configuration whose gross weight is 1,073 kg. Various hypersonic lifting flight data on aerodynamics, thermal protection system, and guidance & control were acquired during the flight. In this paper, the following flight data in respect to hypersonic aerodynamics are briefly reviewed: aerodynamic characteristics, aerodynamic heating, pressure measurements for ADS (Air Data Sensor) and RCS (Reaction Control Subsystem) gas-jet interaction experiment, and electron density around the vehicle. The data are compared with the preflight predictions based on wind tunnel test results and CFD (Computational Fluid Dynamics) calculations in order to investigate validity of the prediction methods., 資料番号: AA0000685009, レポート番号: NAL SP-34

Published
1997

29. Overview of spaceplane development plan at NAL/NASDA

Author

Yamamoto, Masataka

Subjects
小型自動着陸実験, orbit reentry experiment, H 2 orbiting plane, 極超音速飛行実験, 再使用機, HOPE X, automatic landing flight experiment, navigation control, 軌道再突入実験, 宇宙往還技術試験機, J-1ロケット, H-2Aロケット, 誘導制御, hypersonic flight experimental, heat resistant structure, H 2 orbiting plane experimental program, 耐熱構造, H 2A rocket, H-2ロケット打上げ型有翼宇宙往還機, HOPE-X, OREX, HYFLEX, reusable vehicle, HOPE, J 1 rocket, ALFLEX
Abstract

24-25 Jul. 1996, 宇宙技術研究所(NAL)と宇宙開発事業団(NASDA)は協力して、宇宙往還技術試験機(HOPE-X)の開発を進めている。開発は次項の経緯で進められた。(1)1980年代前半から空力、誘導制御、耐熱構造に関する研究、要素の試作試験を開始、(2)1980年後半から10トン級HOPE(H-2ロケット打上げ型有翼宇宙往還機)の概念設計を開始、(3)1994年2月に最初の実験機として軌道再突入実験機(OREX)をH-2ロケットによって打上げた、(4)1996年2月に極超音速飛行実験機(HYFLEX)をJ-1ロケットによって打上げた、(5)1996年より小型自動着陸(ALFLEX)はオーストラリアで飛行試験を続行中、(6)並行して打上げロケットの開発を進め、H-2Aロケットにまで高度化が進展している。HOPE-Xは、2000年度に実験を行うこととして開発を進め、近い将来に、完全再使用型宇宙往還機「HOPE」を目指す。, H-2 Orbiting Plane-experimental (HOPE-X) program has been developing as a joint collaboration between National Aerospace Laboratory (NAL) and National Space Development Agency of Japan (NASDA). The following development histories of HOPE (H-2 Orbiting Plane) are described: (1) in the first half of 1980, research and development of aerodynamics, guidance/control, heat resistant structure, and components test were begun; (2) in the latter half of 1980, conceptual design of ten tons class HOPE were begun; (3) in Feb. 1994, Orbit Reentry-Experimental (OREX) vehicle were launched by H-2 rocket; (4) in Feb. 1996, Hypersonic Flight-Experimental (HYFLEX) vehicle was launched by J-1 rocket; (5) since 1996, flight test of Automatic Landing Flight-Experimental (ALFLEX) vehicle has been going on in Australia; and (6) simultaneously, development of launching rockets has been in progress to realize H-2A rocket with high performance. The HOPE-X is being developed to perform a flight test in 2000. HOPE is expected to be a perfect reusable orbiting plane., 資料番号: AA0000584001, レポート番号: NAL SP-32

Published
1996

30. Evaluation of static strength of T800H/PMR-15 carbon/polyimide laminates at room temperature and 300C

Author

Kakuta, Yoshiaki, Sanbongi, Shigeo, Shimokawa, Toshiyuki, Hamaguchi, Yasumasa, Yamamoto, Masataka, and Mitsuma, Hidehiko

Subjects
静強度試験, ポアッソン比, elastic modulus, temperature effect, H-2ロケット打ち上げ型有翼回収機, H 2 orbiting plane, 材料特性データ, monolayer, 破断ひずみ, material property data, fracture strain, 破壊強度, 引張強度, compression strength, 圧縮強度, interlayer shear strength, カーボン/ポリイミド複合材料, 層間せん断強度, carbon/polyimide composite, laminate strength, 弾性係数, 積層材強度, 単層材, static strength test, tensile strength, Poisson ratio, HOPE, fracture strength, 温度効果
Abstract

本研究の目的は、小型の無人有翼宇宙往還機HOPE(H-2 Orbiting Plane)の主構造用候補材料として選択したカーボン/ポリイミド(T800H/PMR-15)複合材料の単層材特性データの取得と積層材強度を評価することである。室温(RT)および高温(300度C)下で、単層材の基本特性と擬似等方積層材(無孔、有孔)の引張や圧縮強度などを調べるために、種々の静強度試験を行った。単層材の基本特性には、引張強度、圧縮強度、層間せん断強度、破断ひずみ、弾性係数およびポアソン比などが含まれる。積層材に対する破壊強度の解析は、得られた単層材の基本特性をもとにして、無孔試験片の場合に最大応力則とTsai-Wu則、有孔試験片の場合にPoint Stress Criterion法とAverage Stress Criterion法をそれぞれ用いて予測した。これらの解析結果について、試験結果と比較し、検討した。, The objective of this study is to evaluate the material properties and laminate strength of a T800H/PMR-15 carbon/polyimide composite, which is selected as a candidate material for the primary structures of the unmanned small space vehicle HOPE (H-2 Orbiting Plane). Various static tests were conducted to obtain data on the material properties and the laminate strengths for the unnotched and circular-hole-notched specimens of a quasi-isotropic laminate. These tests were conducted at room temperature and a high temperature (300 C). The material property data include tension, compression, and short beam shear strengths, failure strain, elastic modulus, and Poisson's ratio. The first ply failure and the last ply failure strengths of the unnotched laminate are computed using the material property data obtained and the maximum stress and Tsai-Wu failure criteria. The strength of the laminate with a circular hole is predicted on the basis of the point stress and the average stress criteria. These analytical results are compared with the test results and discussed., 資料番号: AA0004261000, レポート番号: NAL TR-1254

Published
1994

31. ON THE HYPERSONIC FLIGHT EXPERIMENT (HYFLEX) PROJECT

Author

Shirouzu, Masao, Inouye, Yasutoshi, Takizawa, Minoru, Kai, Takashi, Yamamoto, Yukimitsu, Fujii, Keisuke, Takaki, Ryouji, Shouji, Hirokazu, Ishimoto, Shinji, Ito, Takeshi, Suzuki, Hirokazu, Yamamoto, Masataka, Watanabe, Shigeya, Shimoda, Takayuki, Teraoka, Ken, Suzuki, Yusuke, Murayama, Shingo, and Saito, Noriyoshi

Abstract

小型の実験機を用いた極超音速飛行実験(HYFLEX)計画がHOPE開発研究の一環として航空宇宙技術研究所と宇宙開発事業団の協力の下で進められている。実験機は2段式のJ-1ロケットにより高度110km、速度約3.9km/sで分離され、滑空飛行中に空力加熱計測、熱防護系評価、誘導制御技術評価等のための飛行データを取得する。本論文は、実験計画の目的、概要、実験機の空力特性、サブシステム、誘導制御則、実験計測及び開発計画等について述べる。, A hypersonic flight experiment project of a lifting-body type vehicle named HYFLEX (Hypersonic Flight Experiment) is in progress by the National Aerospace Laboratory and the National Space Development Agency as a part of collaborative activities for the development of HOPE. The vehicle will be separated at a velocity of about 3.9km/s from the second stage of the J-I launcher and will acquire flight data during its glide descent. This paper describes the purpose and the outline of the experiment, aerodynamic characteristics, sub-components, and guidance and control of the vehicle, as well as onboard data acquisition. and schedule., 資料番号: NALSP0024005, レポート番号: NAL SP-24

Published
1994

32. OUTLINE OF ORBITAL RE-ENTRY EXPERIMENT

Author

Yamamoto, Masataka, Akimoto, Toshio, Yamawaki, Koji, Inaba, Motoyuki, Shimoda, Takayuki, and Inoue, Yasutoshi

Abstract

軌道再突入実験(OREX)は、H-IIロケット打上げ型有翼回収機(HOPE)の研究開発の一環として実施する飛行実験の一つであり、軌道からの大気圏再突入に耐える飛行体の設計・製作技術を蓄積するとともに、地上での試験では取得が困難な再突入時の各種データを取得することにより、HOPEの開発に役立てることを目的としている。軌道再突入実験機は平成6年2月4日種子島宇宙センターからH-IIロケットにより打ち上げられ、地球を一周した後大気圏に再突入し、この間再突入に関する実験データを取得、送信した後、中部太平洋上に着水した。本実験の開発は、航空宇宙技術研究所(NAL)と宇宙開発事業団(NASDA)との共同研究として進められた。, The Orbital Re-entry Experiment (OREX) flight experiment is part of the research for the H-II Orbiting Plane (HOPE). Its purposes are to contribute to HOPE development by accumulating experience in designing and producing a re-entry vehicle and acquiring re-entry data which is difficult to acquire in ground experiments. The OREX vehicle had been launched february 4, 1994 at Tanegashima space center and inserted into orbit by H-II rocket. Vehicle came turn around over the Tanegashima island. It could get experimental data during re-entry, transmited to data the grand stations after re-entry successfully, and splashed down in the Central Pacific Ocean. The OREX project was conducted in cooperation with the National Aerospace Laboratory (NAL) and National Space Development Agency (NASDA)., 資料番号: NALSP0024006, レポート番号: NAL SP-24

Published
1994

33. Statistical analysis of tensile mechanical property data of carbon/polyimide composites

Author

Shimokawa, Toshiyuki, Hamaguchi, Yasumasa, Kakuta, Yoshiaki, Sanbongi, Shigeo, Morino, Yoshiki, and Yamamoto, Masataka

Subjects
B許容値, 修正コルモゴルフ・スミルノフ適合度検定, Gaussian distribution, elastic modulus, ポアソン比, fiber reinforced plastic, B allowable, 対数正規分布, statistical analysis, 破断歪み, 多重回帰分析, extreme value distribution, カーボン・ポリイミド複合材料, 正規分布, 引張強度, 2母数ワイブル分布, modified kolmogolov Smirnov goodness of fit test, multiple regression analysis, 繊維強化プラスチック, Poisson's ratio, 極値分布, carbon/polyimide composite material, 機械的性質, 弾性係数, mechanical property, tensile strength, 統計的解析, long normal distribution, two parameter Weibull distribution, failure strain
Abstract

本研究の目的は、2種類のカーボン/ポリイミド、Celion 6K/PMR-15とT800H/PMR-15準等方積層複合材料について、引張機械的性質を統計的に評価することである。2種の材料それぞれ約30個の平滑試験片を用い、室温において引張試験を実施した。調べた機械的性質は引張強度、破断歪み、弾性係数、ポアソン比である。統計的解析に使用した分布モデルは、正規分布、対数正規分布、極値分布(最小値の2重指数分布)、および2母数ワイブル分布の4種類である。これらの分布形に対して、各機械的性質の代表値、ばらつきの大きさ、ならびにB許容値を計算した。さらに、修正コルモゴロフ・スミルノフ適合度検定と確率紙上にデータをプロットすることにより、機械的性質データそれぞれの4種類の分布モデルに対する適合度を検討した。また、各機械的性質相互間の相関を検討し、引張強度を予測するための重回帰分析を試みた。さらに、破断歪みと弾性係数の積を使用した引張強度の簡易予測式を導いた。, The objective of this study is to statistically evaluate the tensile mechanical properties of two kinds of carbon and polyimide composites, i.e., Celion 6K/PMR-15 and T800H/PMR-15 with a quasi-isotropic stackins sequence. Tensile tests were conducted under room temperature using about thirty smooth specimens each. Mechanical properties measured are ultimate strength, failure strain, elastic modulus, and Poisson,s ratio. Statistical analyses use four kinds of distribution models such as the normal, log-normal,type-1 extreme-value, and two-parameter Weibull distributions. These analyses derive the estimates of central tendencies and scatter parameters, and type B allowables. The modified Kolmosorov-Smirnov goodness-of-fit tests and graphical plotting techniques are applied to test the goodness-of-fit of each mechanical property data for the four kinds of distribution models. Correlation between mutual mechanical properties is examined, and a multiple regression analysis is applied to predict the ultimate strength., 資料番号: AA0004251000, レポート番号: NAL TR-1238

Published
1994

35. Influence of boundary condition on ion energy distribution function

Author

Matsukuma, Masaaki, Yamamoto, Masataka, Kawai, Yoshinobu, and Matsukuma, Masaaki

Subjects
chaos, [PHYS.PHYS.PHYS-PLASM-PH] Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], ion beam, nonlinear saturation mechanism
Abstract

A two stream instability which is named the ion-ion instability is excited by coupling between the ion acoustic mode and the slow ion beam mode. It is well known that this instability goes into turbulent state. However, imposing boundary conditions reduces degrees of freedom of the instability and the chaotic oscillations are observed. Furthermore, it is revealed that the ion-ion instability saturates due to the particle trapping effect. In this paper, it is shown that the growth-rate of the instability with the boundary condition is lowered by a numerical calculation of non local dispersion relation. It is also shown that the ion energy distribution function is influened by the boundary condition.

Published
2004

36. Mechanism of Cancer Cell Death Induced by Hydrogen Discharged from Palladium Base Hydrogen Storage Alloy

Author

Matsuzaki, Makoto, Kagawa, Akio, Motoishi, Aiko, Tanaka, Kunihiko, Yamamoto, Masataka, Tagawa, Yutaka, Matsuzaki, Makoto, Kagawa, Akio, Motoishi, Aiko, Tanaka, Kunihiko, Yamamoto, Masataka, and Tagawa, Yutaka

Abstract

The mechanism of cancer cell death induced by hydrogen discharged from Pd-5at.% Ni hydrogen storage alloy has been investigated. Cancer cell (HeLa: cervical cancer cell) death was observed in the limited region within ~ 3 mm from the sample. The measurement of surviving fraction of cells revealed that almost all the cancer cells in the well of 96-well multi plate, 6.2 mm in diameter were extinct (p < 0.01), while no detectable influence was observed in the normal cells. From the fluorescent imaging experiment, it was indicated that the cell death induced by discharged hydrogen was due to the "Apoptosis" and hydrogen peroxide was detected in both intracellular and extracellular regions. Furthermore, the generation of hydrogen radical and hydroxyl radical was observed in the ESR measurement. From the results obtained, the mechanism of cancer cell death is proposed., 2013 International Conference on Materials Science and Chemical Engineering, MSCE 2013; ; 20 February 2013 ～ 21 February 2013, Advanced Materials Research, 699, pp.284-290; 2013

Published
2013

37. Influence of Active Hydrogen Discharged from Palladium-Nickel Alloy Powder on Biological Cells

Author

Motoishi, Aiko, Kagawa, Akio, Matsuzaki, Makoto, Tanaka, Kunihiko, Yamamoto, Masataka, Tagawa, Yutaka, Motoishi, Aiko, Kagawa, Akio, Matsuzaki, Makoto, Tanaka, Kunihiko, Yamamoto, Masataka, and Tagawa, Yutaka

Abstract

A selective cancer cell death induced by discharged hydrogen from Pd-Ni base hydrogen storage alloy (HSA) powder is demonstrated. From the cell experiment and the measurement of surviving cell rate, it was found that cell death was seen only in cancer cells (HeLa: cervical cancer cell) after 24h- and 48h-immersion of Pd-5at.%Ni alloy powder, while no harmful influence was observed in normal cells (MDCK: renal epithelial cell). The range of cancer cell death was limited just near the HSA powder. It is suggested that the hydrogen radical emitted from the HSA powder induces the formation of hydrogen peroxide and brings a detrimental effect in the cancer cell, while hydrogen peroxide is decomposed by the enzyme, catalase, in normal cells, resulting in the selective death of cancer cells., 2013 International Conference on Materials Science and Chemical Engineering, MSCE 2013; ; 20 February 2013 ～ 21 February 2013, Advanced Materials Research, 699, pp.273-278; 2013

Published
2013

40. Magnetocrystalline anisotropy and magnetic field-induced strain of three martensites in Fe3Pt ferromagnetic shape memory alloys.

Author

Fukuda, Takashi, Yamamoto, Masataka, Yamaguchi, Takashi, and Kakeshita, Tomoyuki

Subjects
*IRON, *MAGNETIC anisotropy, *STRAINS & stresses (Mechanics), *MARTENSITE, *MAGNETIC fields, *PLATINUM, *FERROMAGNETISM, *SHAPE memory alloys
Abstract

Abstract: Magnetocrystalline anisotropy and magnetic field-induced strain were investigated for three tetragonal martensite phases formed in Fe3Pt ferromagnetic shape memory alloys. The phases examined are the body-centered tetragonal (bct, c/a <1) martensite with a degree of order S =0.57, the face-centered tetragonal (fct, c/a <1) martensite with S =0.75 and the fct (c/a >1) martensite with S =0.88. It was found that the c-axis is the easy axis of magnetization for the two fct martensites and the hard axis of magnetization for the bct martensite. The uniaxial magnetocrystalline anisotropy constant, K u, is nearly proportional to |1− c/a| for the two fct martensites, but the relation is not satisfied for the bct phase. When a magnetic field is applied in the [001] direction, a large magnetic field-induced strain appears in the two fct martensites but not in the bct martensite. The strain in the field direction is a contraction in the fct martensite with c/a < 1, whereas it is an expansion in the fct martensite with c/a >1. These behaviors are explained by evaluating the magnetic shear stress, which is given by K u divided by the twinning shear. [Copyright &y& Elsevier]

Published
2014
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41. Experimental and theoretical studies on the intramolecular charge-transfer emission of phenyldisilanes

Author

Yamamoto, Masataka, Kudo, Takako, Ishikawa, Mitsuo, Tobita, Seiji, and Shizuka, Haruo

Subjects
Silane -- Research, Organosilicon compounds -- Research, Charge transfer -- Research, Polyvinyl alcohol -- Research, Chemicals, plastics and rubber industries
Abstract

The intramolecular charge-transfer (ICT) emission of phenylpentamethyldisilane and its para-substituted derivatives, -C(CH3)3, -OCH3 and -N(CH3)2, have been studied through ab initio calculations on a poly(vinyl alcohol) film at 77 K. Results indicate the presence of ICT fluorescence and locally-excited (LE) emission for the first three compounds. No dynamic equilibrium was observed between the ICT and LE states, which suggest that the ICT state originates from the nonrelaxed excited singlet (Sn) state.

Published
1999

44. A new type of FCT martensite phase in single-crystalline Fe3Pt Invar alloy

Author

Yamamoto, Masataka, Sekida, Sayaka, Fukuda, Takashi, Kakeshita, Tomoyuki, Takahashi, Kohki, Koyama, Keiichi, and Nojiri, Hiroyuki

Subjects
*MARTENSITIC transformations, *IRON alloys, *MAGNETIZATION, *X-ray diffraction, *TRANSMISSION electron microscopy, *MAGNETIC measurements, *TEMPERATURE effect
Abstract

Abstract: Martensitic transformation in a highly ordered Fe3Pt has been investigated by magnetization and X-ray diffraction measurements. We confirmed that a new type of face-centered tetragonal (FCT) martensite phase appears below 60K in Fe3Pt with a degree of order S =0.88. The tetragonality c/a gradually increases with decreasing temperature, and is approximately 1.005 at 10K. This is in contrast to the tetragonality c/a <1 generally observed in the FCT martensite with a degree of order less than 0.8. The spontaneous magnetization increases in association with the transformation. [Copyright &y& Elsevier]

Published
2011
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