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-AlOOH under mantle conditions using neutron diffractionSano, Asami; Hattori, Takanori; Komatsu, Kazuki*; Kagi, Hiroyuki*; Nagai, Takaya*; Molaison, J. J.*; Dos Santos, A. M.*; Tulk, C. A.*
Scientific Reports (Internet), 8(1), p.15520_1 - 15520_9, 2018/10
Times Cited Count：44 Percentile：92.58(Multidisciplinary Sciences)The pressure response of hydrogen bond in aluminous hydroxide -AlOOH, which is an important candidate for water carrier to the deep Earth in a subducting slab, was investigated using neutron diffraction under high pressure. The symmetrization of hydrogen bond in which hydrogen locates at the center between two oxygen atoms was observed directly for the first time. The present result indicates that the changes of mineral properties such as increase in bulk modulus and sound velocities, which were previously found, were induced by the symmetrization and disorder state that was also found at just below the symmetrization pressure. Even the symmetrization is a small change in the hydrogen location but it is playing an important role in determining the physical properties of minerals.
Hattori, Takanori; Sano, Asami; Arima, Hiroshi*; Komatsu, Kazuki*; Yamada, Akihiro*; Inamura, Yasuhiro; Nakatani, Takeshi; Seto, Yusuke*; Nagai, Takaya*; Utsumi, Wataru; et al.
Nuclear Instruments and Methods in Physics Research A, 780, p.55 - 67, 2015/04
Times Cited Count：75 Percentile：98.97(Instruments & Instrumentation)PLANET is a time-of-flight (ToF) neutron beamline dedicated to high-pressure and high-temperature experiments. The large six-axis multi-anvil high-pressure press designed for ToF neutron diffraction experiments enables routine data collection at high pressures and high temperatures up to 10 GPa and 2000 K, respectively. To obtain clean data, the beamline is equipped with the incident slits and receiving collimators to eliminate parasitic scattering from the high-pressure cell assembly. The high performance of the diffractometer for the resolution (
/ 
0.6%) and the accessible -spacing range (0.2-8.4 
) together with low-parasitic scattering characteristics enables precise structure determination of crystals and liquids under high pressure and temperature conditions.
Iizuka, Riko*; Komatsu, Kazuki*; Kagi, Hiroyuki*; Nagai, Takaya*; Sano, Asami; Hattori, Takanori; Goto, Hirotada*; Yagi, Takehiko*
Journal of Solid State Chemistry, 218, p.95 - 102, 2014/10
Times Cited Count：7 Percentile：33.52(Chemistry, Inorganic & Nuclear)In situ neutron diffraction measurements combined with the pulsed neutron source at the Japan Proton Accelerator Research Complex (J-PARC) were conducted on high-pressure polymorphs of deuterated portlandite (Ca(OD)
) using a Paris-Edinburgh cell and a multi-anvil press. The atomic positions including hydrogen for the unquenchable high-pressure phase at room temperature (phase II') were first clarified. The bent hydrogen bonds under high pressure were consistent with results from Raman spectroscopy. The structure of the high-pressure and high-temperature phase (Phase II) was concordant with that observed previously by another group for a recovered sample. The observations elucidate the phase transition mechanism among the polymorphs, which involves the sliding of CaO polyhedral layers, position modulations of Ca atoms, and recombination of Ca-O bonds accompanied by the reorientation of hydrogen to form more stable hydrogen bonds.
Iizuka, Riko*; Kagi, Hiroyuki*; Komatsu, Kazuki*; Ushijima, Daichi*; Nakano, Satoshi*; Sano, Asami; Nagai, Takaya*; Yagi, Takehiko*
Physics and Chemistry of Minerals, 38(10), p.777 - 785, 2011/12
Times Cited Count：10 Percentile：33.16(Materials Science, Multidisciplinary)The pressure responses of portlandite and the isotope effect on the phase transition were investigated at room temperature from single-crystal Raman and IR spectra and from powder X-ray diffraction using diamond anvil cells under quasi-hydrostatic conditions in a helium pressure-transmitting medium. Phase transformation and subsequent peak broadening observed from the Raman and IR spectra of Ca(OH) occurred at lower pressures than those of Ca(OD). In contrast, no isotope effect was found on the volume and axial compressions observed from powder X-ray diffraction patterns. X-ray diffraction lines attributable to the high-pressure phase remained up to 28.5 GPa, suggesting no total amorphization in a helium pressure medium within the examined pressure region. These results suggest that the H-D isotope effect is engendered in the local environment surrounding H(D) atoms.
Utsumi, Wataru; Kagi, Hiroyuki*; Komatsu, Kazuki*; Arima, Hiroshi*; Nagai, Takaya*; Okuchi, Takuo*; Kamiyama, Takashi*; Uwatoko, Yoshiya*; Matsubayashi, Kazuyuki*; Yagi, Takehiko*
Nuclear Instruments and Methods in Physics Research A, 600(1), p.50 - 52, 2009/02
Times Cited Count：13 Percentile：64.57(Instruments & Instrumentation)The application of high pressure can induce dramatic changes in the physical properties of condensed matter. Diffraction experiments under high pressure provide precise structural information, which is fundamental to understand their origin. When in situ high pressure neutron diffraction becomes possible at J-PARC, further outstanding researches are expected such as crystal structure of hydrogen-bearing materials including hydrous minerals, order-disorder transitions of minerals, structure of light element liquid at high pressure, etc.. Conceptual designs of neutron optics and high pressure devices for J-PARC are introduced.
Terada, Hiroaki; Nagai, Haruyasu; Furuno, Akiko; Kakefuda, Toyokazu; Harayama, Takaya*; Chino, Masamichi
Nihon Genshiryoku Gakkai Wabun Rombunshi, 7(3), p.257 - 267, 2008/09
The second version of WSPEEDI (WSPEEDI-II) which has functions to predict the radiological impact of nuclear accident abroad on Japan by quick calculations of air concentration, surface deposition and radiological doses is developed. WSPEEDI-II has the following functions for practical use. (1) High performance prediction of atmospheric dispersion of radionuclides from local to regional ranges with appropriate resolutions by introducing non-hydrostatic atmospheric dynamic model. (2) Source term estimation by coupling calculation results and monitoring data for the case that no source information is available from abroad. (3) On-line prediction data exchanges with major emergency response systems in the United States and Europe with the similar functions as WSPEEDI-II. (4) Web-based graphical user interface system for easy operation of WSPEEDI-II. (5) Preset East-Asian database for the quick start against a nuclear accident in Eastern Asia. This paper describes these new functions.
Nagai, Haruyasu; Chino, Masamichi; Terada, Hiroaki; Harayama, Takaya*; Kobayashi, Takuya; Tsuzuki, Katsunori; Kim, K.; Furuno, Akiko
JAEA-Research 2006-057, 67 Pages, 2006/09
JAEA-Research-2006-057.pdf:13.49MB
A numerical simulation system SPEEDI-MP has been developed to apply for various environmental studies. SPEEDI-MP consists of dynamical models and material transport models for the atmospheric, terrestrial, and oceanic environments, database for model inputs, and system utilities for file management, visualization, etc. As a numerical simulation tool, a model coupling program (model coupler) has been developed. A coupled model system for water circulation has been constructed with atmosphere, ocean, wave, hydrology, and land-surface models using the model coupler. System utility GUIs are based on the Web technology, allowing users to manipulate all the functions on the system using their own PCs via the internet. In this system, the source estimation function in the atmospheric transport model can be executed on the grid computer system. Performance tests of the coupled model system for water circulation were also carried out for the flood and the storm surge events.
Yoshiasa, Akira*; Murai, Keiichiro*; Nagai, Takaya*; Katayama, Yoshinori
Japanese Journal of Applied Physics, Part 1, 40(4A), p.2395 - 2398, 2001/04
Times Cited Count：5 Percentile：26.27(Physics, Applied)The pressure dependence of extended X-ray absorption fine structure (EXAFS) Debye-Waller factors in AgBr has been investigated using the cumulant expansion method. The Br K-edge EXAFS spectra were measured in the transmission mode under high pressure (
9.1GPa) at room temperature using a cubic anvil type apparatus (MAX90) and synchrotron radiation from the Photon Factory, Tsukuba. The effective pair potentials 
, were evaluated and the potential coefficient 
at 2.1, 4.2 and 6.1GPa are 1.59(4), 1.75(4) and 1.91(4) eV/
, respectively. The energies of the third-order anharmonic potential coefficient 
maintain nearly constant values with pressure though the third-order cumulant 
decreases with increasing in pressure.
Fukui, Hiroyuki*; Otaka, Osamu*; Nagai, Takaya*; Katsura, Tomoo*; Funakoshi, Kenichi*; Utsumi, Wataru
Physics and Chemistry of Minerals, 27(6), p.367 - 370, 2000/06
Times Cited Count：4 Percentile：21.48(Materials Science, Multidisciplinary)no abstracts in English
under high-temperature and high-pressure conditionsFukui, Hiroyuki*; Otaka, Osamu*; Katsura, Tomoo*; Nagai, Takaya*; Funakoshi, Kenichi*; Utsumi, Wataru; Kikegawa, Takumi*
Science and Technology of High Pressure, p.554 - 557, 2000/00
no abstracts in English
Hattori, Takanori; Arima, Hiroshi; Sano, Asami; Utsumi, Wataru; Nagai, Takaya*; Iitaka, Toshiaki*; Kagi, Hiroyuki*; Katayama, Yoshinori; Inoue, Toru*; Yagi, Takehiko*
no journal, ,
The PLANET is the new high-pressure neutron beamline now being constructed at the intense pulsed neutron source J-PARC. This beamline aims at revealing the effect of water on dynamics of the interior of the Earth and planets by using the neutron character that is sensitive to hydrogen. The most characteristic feature of this beamline is to posses the huge 6-axis press with the maximum load of 500 ton/axis, which can simultaneously generate high-pressure and high-temperature condition of 30 GPa and 2000 K. Coupled with the state-of-the-art techniques in neutron diffraction and radiography, the beamline offers the microscopic and macroscopic information of materials at high-PT condition.
Sano, Asami; Komatsu, Kazuki*; Kagi, Hiroyuki*; Nagai, Takaya*; Hattori, Takanori
no journal, ,
-AlOOH, distorted rutile type oxyhydroxide is an important hydrous mineral in the deep earth because it is stable at the lower mantle condition. X-ray diffraction study found the change in the compressibility at high pressure which would be attributed to the symmetrization of hydrogen bond, but there is a difference in the pressure where the compression behaviors change. To investigate the D/H isotope effect on the symmetrization, high pressure neutron diffraction experiments were conducted at SNAP, SNS. The intensity of 120 reflection continues to decrease at high pressure and become almost zero intensity at 6.7 GPa, suggesting the transition from P2
nm to Pnnm as a precursor of the symmetrization. Strong D/H isotope effect was found in the hydrogen bond geometry; O-H distances are longer than O-D whereas H...O distances are shorter than D...O.
Hattori, Takanori; Arima, Hiroshi; Sano, Asami; Abe, Jun; Utsumi, Wataru; Nagai, Takaya*; Kagi, Hiroyuki*; Iitaka, Toshiaki*; Katayama, Yoshinori; Inoue, Toru*; et al.
no journal, ,
The high-pressure neutron diffractometer PLANET is the new spectrometer dedicated for high-pressure experiments, which is now being constructed in MLF at J-PARC. The main purpose is to investigate the effect of the water on the Earth's dynamics with the help of the neutron. One of the most characteristic features is the huge 6ram 6axes press with the maximum centric load to 3000 tonf, which enables us to investigate the structure of crystals, liquids and amorphous solids under high-pressure and high-temperature conditions of 30GPa and 2000K. We have installed several optical devices, such as choppers, supermirror guides, 4-dimensional slit, and data acquisition system. On the last March, we received FIRST NEUTRON BEAM. In the talk, we overview the spectrometer and introduce the current construction state.
Hattori, Takanori; Arima, Hiroshi; Sano, Asami; Utsumi, Wataru; Katayama, Yoshinori; Nagai, Takaya*; Inoue, Toru*; Kagi, Hiroyuki*; Yagi, Takehiko*
no journal, ,
The PLANET is the new high-pressure neutron beamline now being constructed at the intense pulsed neutron source J-PARC. This beamline aims at revealing the effect of water on dynamics of the interior of the Earth and planets by using the neutron character that is sensitive to hydrogen. The most characteristic feature of this beamline is to posses the huge 6-axis press with the maximum load of 500 ton/axis, which can simultaneously generate high-pressure and high-temperature condition of 30 GPa and 2000 K. Coupled with the state-of-the-art techniques in neutron diffraction and radiography, the beamline offers the microscopic and macroscopic information of materials at high-PT condition. We stared designing at 2008 and already installed all the beamline components except those scheduled to be installed inside the experimental hutch. The huge press and detector banks have been constructed and are waiting to be installed. We received the first beam on March 7, and held the first beam ceremony on March 11.
-AlOOH at high pressureSano, Asami; Komatsu, Kazuki*; Hattori, Takanori; Nagai, Takaya*; Kagi, Hiroyuki*; Molaison, J.*; Moreira Dos Santos, A.*; Tulk, C.*
no journal, ,
-AlOOH is a high pressure polymorph of diaspore. Previous theoretical studies predict that hydrogen bond become symmetric at high pressure. Neutron diffraction experiment at high pressure found that O-D bond is elongated at high pressure, in support these predictions. Powder X-ray diffraction studies also found that the change in compressibility occurs at high pressure. To investigate the sequence to the symmetrization and its relation with the change in compressibility, we conducted neutron diffraction experiments on -AlOOH was conducted at SNAP, SNS. The results suggest the transition from hydrogen ordered structure to disordered structure at 6.7 GPa. Strong DH isotope effect was also found in the hydrogen bond geometry at high pressure.
Hattori, Takanori; Arima, Hiroshi; Sano, Asami; Utsumi, Wataru; Nagai, Takaya*; Iitaka, Toshiaki*; Kagi, Hiroyuki*; Katayama, Yoshinori; Inoue, Toru*; Yagi, Takehiko*
no journal, ,
The PLANET is the new high-pressure neutron beamline now being constructed at the intense pulsed neutron source J-PARC. This beamline aims at revealing the effect of water on dynamics of the interior of the Earth and planets by using the neutron character that is sensitive to hydrogen. The most characteristic feature of this beamline is to posses the huge 6-axis press with the maximum load of 500 ton/axis, which can simultaneously generate high-pressure and high-temperature condition of 30GPa and 2000 K. Coupled with the state-of-the-art techniques in neutron diffraction and radiography, the beamline offers the microscopic and macroscopic information of materials at high-PT condition. We stared designing at 2008 and already installed all the beamline components except those scheduled to be installed inside the experimental hutch. The huge press and detector banks have been constructed and are waiting to be installed. The installation will be finished in 2011, and the commissioning will starts at 2012.
Hattori, Takanori; Sano, Asami; Arima, Hiroshi*; Inamura, Yasuhiro; Yamada, Akihiro*; Komatsu, Kazuki*; Nagai, Takaya*; Katayama, Yoshinori; Inoue, Toru*; Kagi, Hiroyuki*; et al.
no journal, ,
The PLANET is the high-pressure neutron beamline newly constructed at Japanese pulsed neutron source J-PARC. The most characteristic feature of this beamline is to possess the huge 6-axis multi-anvil press with the maximum load of 500 ton per axis. By combining with time-of-flight neutron diffraction and neutron radiography techniques, we can observe high-pressure and high-temperature state of the matter at 10 GPa and 2000 K. To eliminate scattering from sample surrounding materials, we designed and installed the severe incident and receiving collimators. This can confine the diffraction gauge volume into less than 3 mm cube, which results in no contamination of sample diffraction pattern. This character has a big advantage in solving unidentified structures of high-pressure phases as well as the precise structure refinement.
Hattori, Takanori; Sano, Asami; Shioya, Masahiro; Yamada, Akihiro*; Arima, Hiroshi*; Inoue, Toru*; Inamura, Yasuhiro; Ito, Takayoshi*; Komatsu, Kazuki*; Kagi, Hiroyuki*; et al.
no journal, ,
The PLANET is the world's first neutron beamline specialized for high-pressure and high-temperature experiments. The most characteristic feature is the capability to investigate the state of the matter at high-pressure and high-temperatures up to 20 GPa and 2000 K with the multi-anvil high-pressure apparatus. The construction was started in 2008, and the beamline was commissioned in the last spring. The performance revealed by the commissioning will be introduced. The resolution of the diffraction pattern (d/d = 0.6%) was found to be almost equal to the designed value (0.5%). The elimination of the background from the sample surrounding materials, which is the most important feature of the high-pressure experiments, was found to be accomplished with the use of the severe incident collimator and radial receiving collimator system. The beamline is used by project members since this autumn and will be opened for general users in the next April.
Hattori, Takanori; Sano, Asami; Arima, Hiroshi*; Nagai, Takaya*; Utsumi, Wataru; Iitaka, Toshiaki*; Kagi, Hiroyuki*; Katayama, Yoshinori; Inoue, Toru*; Yagi, Takehiko*
no journal, ,
The PLANET is the new high-pressure neutron beamline constructed at the intense pulsed neutron source J-PARC. This beamline aims at revealing the effect of water on dynamics of the interior of the Earth and planets by using the neutron character that is sensitive to hydrogen. The most characteristic feature of this beamline is to possess the huge 6-axis press with the maximum load of 500 ton/axis, which can simultaneously generate high-pressure and high-temperature condition of 20 GPa and 2000 K (see Sano-Furukawa et al.). Coupled with the state-of-the-art techniques of neutron diffraction and radiography, the beamline offers the microscopic and macroscopic information of materials at high-PT condition. In the last Spring, we finished the beam commissioning. I introduce the general feature of this beamline and the specification revealed by the commissioning. The beamline is used by the project members before the next March, and then it will be opened for general users.
Hattori, Takanori; Sano, Asami; Arima, Hiroshi*; Komatsu, Kazuki*; Yamada, Akihiro*; Nagai, Takaya*; Katayama, Yoshinori; Inoue, Toru*; Utsumi, Wataru; Kagi, Hiroyuki*; et al.
no journal, ,
The PLANET is the world's first neutron beamline specialized for high-pressure and high-temperature experiments. The most characteristic feature is the capability to investigate the state of the matter at high-pressure and high-temperatures up to 20 GPa and 2000 K with the multi-anvil high-pressure apparatus. The construction was started in 2008. The beamline was commissioned in the first half year of JFY 2012 and the new data is being taken by project members. This year, the beamline is reborn to a public beamline of J-PARC. In this talk, the performance of the PLANET and the typical results are introduced. The resolution of the diffraction pattern (d/d=c.a 0.6%) was found to be almost equal to the designed value (0.5%). The elimination of the background from the sample surrounding materials, which is the most important feature of the high-pressure experiments, was found to be accomplished with the use of the severe incident collimator and radial receiving collimator system. The beamline is opened for general users since the last half year of JFY2013 (from Feb.).
