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observation of recrystallization of aluminum single crystals using synchrotron radiation monochromatic X-raysShiro, Ayumi*; Shobu, Takahisa; Okada, Tatsuya*
Zairyo, 71(4), p.354 - 360, 2022/04
Recrystallization process of an aluminum (Al) single crystal was observed in situ using synchrotron X-rays. Al single-crystalline samples were deformed in tension along a 
111
direction to a strain of 8%, and were subsequently annealed at 753 K. The changes in the shape and intensity of diffraction spots were analyzed using a two-dimensional detector. A diffraction spot from the deformation matrix had three peaks which reflected a sub-grained microstructure of the sample. The 
observation during annealing unveiled the appearance of diffraction spots from a recrystallized grain at 330.8 s. As the diffraction spots from the recrystallized grain became larger, the diffraction spots from the deformation matrix gradually disappeared. The application of the X-ray topography method revealed the crystal orientation variation in a recrystallized grain in order of 0.001 degree.
synchrotron radiation observation of deformation and annealing processes of aluminum single crystalShiro, Ayumi*; Okada, Tatsuya*; Shobu, Takahisa
Mechanical Engineering Journal (Internet), 8(6), p.21-00106_1 - 21-00106_8, 2021/12
The objective of the present study was to carry out observations of deformation and annealing processes of aluminum single crystals using a synchrotron radiation X-rays at SPring-8. Al single-crystalline samples having a 111 orientation parallel to the longitudinal direction were grown by a Bridgman method. The samples were deformed in tension to a nominal strain of 0.08 at room temperature using an in-line tensioning apparatus. Post-deformation annealing at 480 
C was subsequently carried out in the same apparatus. A two-dimensional detector was used to detect multiple diffracted beams from the sample during the deformation and annealing processes. The volume irradiated by the X-ray beam was found to be composed of three regions having a small orientation difference, which was attributable to sub-grained microstructures of the sample. Detailed analyses of a diffraction spot intensity showed that the sub-grained microstructures were surpassed by dislocated microstructures with the increase in the tensile strain. During the post-deformation annealing, diffraction spots from a recrystallized grain first appeared at 180 s after the temperature reached 480 C. Coexistence of diffraction spots from the deformation matrix and recrystallized grain lasted only for about 22 s in the irradiated volume. The migration rate of the boundary between the deformation matrix and recrystallized grain was estimated to be of the order of several micrometers/s.
Wada, Yuki*; Matsumoto, Takahiro*; Enoto, Teruaki*; Nakazawa, Kazuhiro*; Yuasa, Takayuki*; Furuta, Yoshihiro*; Yonetoku, Daisuke*; Sawano, Tatsuya*; Okada, Go*; Nanto, Hidehito*; et al.
Physical Review Research (Internet), 3(4), p.043117_1 - 043117_31, 2021/12
Abderrahmane, A.*; Takahashi, Hiroki*; Tashiro, Tatsuya*; Ko, P. J.*; Okada, Hiroshi*; Sato, Shinichiro; Oshima, Takeshi; Sandhu, A.*
AIP Conference Proceedings 1585, p.123 - 127, 2014/02
Times Cited Count：1 Percentile：50.83(Physics, Applied)The effect of annealing at 673 K on irradiated micro-Hall sensors irradiated with protons at 380 keV and fluences of 1
cm
, 1
cm, 1
cm is reported. Cathodoluminescence measurements were carried out at room temperature before and after annealing and showed improvement in the band edge band emission of the GaN layer. After annealing a sensor irradiated by 1 cm the device became operational with improvements in its magnetic sensitivity. All irradiated sensors showed improvement in their electrical characteristics after annealing.
Abderrahmane, A.*; Tashiro, Tatsuya*; Takahashi, Hiroki*; Ko, P. J.*; Okada, Hiroshi*; Sato, Shinichiro; Oshima, Takeshi; Sandhu, A.*
Applied Physics Letters, 104(2), p.023508_1 - 023508_4, 2014/01
Times Cited Count：6 Percentile：26.59(Physics, Applied)The effect of annealing on the magnetoelectrical properties of proton-irradiated micro-Hall sensors at an energy of 380 keV and very high proton fluences was studied. Recovery of the electron mobility and a decrease in the sheet resistance of the annealed micro-Hall sensors, as well as an enhancement in their magnetic sensitivity were reported. Trap removal and an improvement in the crystal quality by removing defects were confirmed through current-voltage measurements and Raman spectroscopy, respectively.
Koyama, Shinichi; Suzuki, Tatsuya*; Ozawa, Masaki*; Kurosawa, Kiyoko*; Fujita, Reiko*; Mimura, Hitoshi*; Okada, Ken*; Morita, Yasuji; Fujii, Yasuhiko*
Procedia Chemistry, 7, p.222 - 230, 2012/00
Times Cited Count：2 Percentile：70.77(Chemistry, Analytical)Adv.-ORIENT cycle strategy has been proposed as a basic concept for trinitarian research on separation, transmutation and utilization of nuclides and elements based on FBR fuel cycle. Validation of principal separation method and related safety research were performed from 2006 through 2011 as Phase I program. First, more than 90% of Cs could be recovered from the actual spent fuel [IXC(I) step]. The next is the adsorption of the platinum group metals (PGM), lanthanides, Am and Cm were separated by using a tertiary pyridine-type resin (TPR) as ion exchange steps [IXC(II, III, IV) steps]. The separated PGM metals will be supplied to the electrochemical extraction [CEE step]. As experiment for safety issues, Hastelloy-B at RT and Ta at 90C were confirmed their anti-corrosive in highly concentrated HCl media. Thermo-chemical stability for TPR was verified. Issues to be solved for next phase based on the final results of phase I program.
Koyama, Shinichi; Yamagishi, Isao; Suzuki, Tatsuya*; Ozawa, Masaki*; Fujita, Reiko*; Okada, Ken*; Tatenuma, Katsuyoshi*; Mimura, Hitoshi*; Fujii, Yasuhiko
Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 8 Pages, 2011/12
Effective separation of MA and LLFP, transmutation and utilization were the main directions of Advanced OREINT Cycle project. Study for each integrant technology was concluded as first trial of the project. TPR enabled to separate MA/Ln and then Am/Cm precisely from spent fuel in HCl and HNO
media. CEE method could separate the light PGM and Tc by HCl media. Recovery of Cs from simulated HLLW coul be achieved more than 90 %. In addition, the perspective for next phase was proposed.
Koyama, Shinichi; Suzuki, Tatsuya*; Mimura, Hitoshi*; Fujita, Reiko*; Kurosawa, Kiyoko*; Okada, Ken*; Ozawa, Masaki
Progress in Nuclear Energy, 53(7), p.980 - 987, 2011/09
Times Cited Count：5 Percentile：38.41(Nuclear Science & Technology)Individual basic researches of separation step were performed in the Advanced ORIENT Cycle project. High separation selectivity for Cs and Sr by novel nano adsorbents AMP-SG (D) and D18C6-MC were confirmed, respectively. TPR well adsorbed Pd and Tc in dilute HCl condition. Formation of rare metal fission product RMFP-deposit Pt electrodes from SHLLW was verified, and it was confirmed that high catalytic reactivity on electrolytic production of hydrogen. As experiment for engineering feasibility, Hastelloy-B at RT and Ta at 90C were confirmed their anti-corrosive in highly concentrated HCl media. Thermo-chemical stability for TPR was verified in either HCl or HNO media toward its practical use in the separation process. Issues to be solved for optimization based on the results of lab-scale experiment have revealed in this study.
collisions at 
= 200 and 62.4 GeVAdare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06
Times Cited Count：184 Percentile：99.42(Physics, Nuclear)Transverse momentum distributions and yields for 
, and 
in collisions at = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different collisions. We also present the scaling properties such as 
and 
scaling and discuss the mechanism of the particle production in collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.
and Au+Au collisions at 
= 200 GeVAdare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.
Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04
Times Cited Count：9 Percentile：52.86(Physics, Nuclear)Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.
Tanaka, Naritake*; Kimura, Hitoshi*; Faried, A.*; Sakai, Makoto*; Sano, Takaaki*; Inose, Takanori*; Soda, Makoto*; Okada, Koji*; Nakajima, Masanobu*; Miyazaki, Tatsuya*; et al.
Cancer Science, 101(6), p.1487 - 1492, 2010/06
Times Cited Count：12 Percentile：31.63(Oncology)We examined the intracellular localization of cisplatin, a key chemotherapeutic agent, in esophageal cancer cell lines and determined their sensitivity to cisplatin using in-air micro-PIXE. Two human esophageal squamous cell carcinoma (ESCC) cell lines, TE-2 and TE-13, were examined for their response to cisplatin using MTT assay, flow cytometry and DNA fragmentation assays. Real-time reverse transcription-polymerase chain reaction was also used to evaluate the mRNA expression of multidrug resistance protein 2 (MRP2) in both cell lines. Platinum localizations of intracellular and intranuclear were measured using in-air micro-PIXE. TE-2 cells were more sensitive to cisplatin than TE-13 cells. The results of this study suggest that in-air micro-PIXE could be a useful quantitative method for evaluating the cisplatin sensitivity of individual cells. Finally, we speculate that MRP2 in the cell membrane may play an important role in regulating cisplatin sensitivity of ESCC cells.
Ozawa, Masaki; Suzuki, Tatsuya*; Koyama, Shinichi; Yamagishi, Isao; Fujita, Reiko*; Okada, Ken*; Tatenuma, Katsuyoshi*; Mimura, Hitoshi*; Fujii, Yasuhiko*
Proceedings of International Conference on Advanced Nuclear Fuel Cycle; Sustainable Options & Industrial Perspectives (Global 2009) (CD-ROM), p.1117 - 1126, 2009/09
Sato, Yoshihiko*; Okada, Ken*; Akiyoshi, Miyako*; Matsunaga, Takehiro*; Suzuki, Tatsuya*; Koyama, Shinichi; Ozawa, Masaki
Proceedings of International Conference on Advanced Nuclear Fuel Cycle; Sustainable Options & Industrial Perspectives (Global 2009) (CD-ROM), p.962 - 969, 2009/09
The fundamental thermochemical properties of tertiary pyridine resin (TPR) and its mixtures with methanol/HCl and HNO were investigated and heating tests on gram scale with TPR/methanol/HNO were carried out. It was found that TPR with HCl was thermally stable. Evident thermal decomposition peaks were identified with TPR in the presence of concentrated HNO. No specific effect was observed for methanol involving. However, it was considered that the rapidly exothermic reaction can be controlled by heating temperature.
Koyama, Shinichi; Ozawa, Masaki; Okada, Ken*; Kurosawa, Kiyoko*; Suzuki, Tatsuya*; Fujii, Yasuhiko*
Proceedings of International Conference on Advanced Nuclear Fuel Cycles and Systems (Global 2007) (CD-ROM), p.1530 - 1536, 2007/09
Simplified separation process was proposed based on ion-exchange technique. HCl, HNO and MeOH were used as an eluent. To develop an engineering scale concept, it is indispensable to establish the condition for safety operation. Corrosion test of structural materials in the HCl was performed by using some metals. In this experiment, it was proved that the Ta, Zr, Nb and hastelloy have good endurance to HCl solution. Research of thermal hazard of pyridine-type ion-exchange resin, MeOH and HNO media system was studied in the view point of fire and explosion safety. There is no hazardous reaction between IER/MeOH, HNO media system. In the case of more than 150C, we should pay attention to the exothermic reaction at dried condition NO-IER or IER/HNO media system.
Kagohara, Kyoko*; Imaizumi, Toshifumi*; Miyauchi, Takahiro*; Sato, Hiroshi*; Uchida, Takuma*; Echigo, Tomoo*; Ishiyama, Tatsuya*; Matsuta, Nobuhisa*; Okada, Shinsuke*; Ikeda, Yasutaka*; et al.
Chigaku Zasshi, 115(6), p.691 - 714, 2006/12
The eastern marginal fault zone of the Yokote Basin is one of seismogenic reverse faults developed in Northeast Japan, generating the 1896 Riku-u Earthquake (M7.2). We discussed the relationship among fault traces, geomorphic displacements and fault geometries on the Senya fault, based on a data from high-resolution seismic reflection profiling, investigations in tectonic geomorphology and structural geology, with the help of the balanced cross section method. By the restoring the balanced cross sections, the horizontal shortening amount is estimated to be totally 3 km through the thrust system, and the thrusting is retroactive to 2.4 Ma. Depending on the strike of fault traces and the morphotectonic features, the Senya fault is subdivided into three, the northern, central and southern portion. The initiation of thrust front migration is ca.1.6 Ma at the central portion and 0.6 Ma at the northern portion. This means that the central portion preceded the northern portion as an emergent fault, and suggests that the initial propagated fault extends from the fault end to the boundary fault.
measurement of lattice strain under plastic deformation in Aluminum single crystalShiro, Ayumi; Shobu, Takahisa; Okada, Tatsuya*; Kawano, Tomoya*; Bunya, Hirotomo*
no journal, ,
Aluminum single crystals deformed along the 111 direction exhibit a macroscopically uniform multiple-slip without deformation bands. In a previous study, it was found that the residual strain of Al single crystal deformed to a tensile strain of 8% to the 111 direction is very small. In this study, in order to clarify the strain distribution under tensile deformation, we carried out the 
measurement using 2-dimensional detector. As a result, it was found as follows: (1) The width of diffraction spots were broadening as a plastic deformation was large. (2) Three subcrystals existed in the aluminum single crystal, and each subcrystal has different strain. (3) The relationship between the width of diffraction spot and formation behavior of the internal dislocation substructure existed.
Ito, Tatsuya; Ogawa, Yuhei*; Gong, W.; Kawasaki, Takuro; Okada, Kazuho*; Shibata, Akinobu*; Harjo, S.
no journal, ,
no abstracts in English
Ito, Tatsuya; Ogawa, Yuhei*; Gong, W.; Mao, W.; Kawasaki, Takuro; Okada, Kazuho*; Shibata, Akinobu*; Harjo, S.
no journal, ,
no abstracts in English
Okada, Ken*; Sato, Yoshihiko*; Akiyoshi, Miyako*; Matsunaga, Takehiro*; Suzuki, Tatsuya*; Koyama, Shinichi; Ozawa, Masaki
no journal, ,
Thermal stability of mixtures of silica-supported tertiary pyridine resin/MeOH/HNO systems was evaluated in order to confirm the fire and exposure property by ARC (Accelerating Rate Calorimeter). As the results, more than 0.02 K heat was detected from around 109C in the case of HNO type resin. Therefore it is expected that the vigorous exothermic reaction is occurred.
Sato, Yoshihiko*; Okada, Ken*; Koyama, Shinichi; Suzuki, Tatsuya*; Ozawa, Masaki*; Matsunaga, Takehiro*
no journal, ,
Thermal stability of mixtures of silica-supported tertiary pyridine resin/MeOH/HNO systems was evaluated in order to confirm the exothermic property and pressure change on an adiabatic process using ARC (Accelerating Rate Calorimeter). As the results, it is expected that the vigorous reaction is occurred at least more than 80C by exothermic reaction between MeOH and HNO.
