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Yamashita, Takayuki; Morooka, Satoshi; Koga, Norimitsu*; Umezawa, Osamu*
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no abstracts in English
Morooka, Satoshi; Kawasaki, Takuro; Harjo, S.; Nakada, Nobuo*; Tsukada, Yuki*
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no abstracts in English
Nakagawa, Hiroshi; Saio, Tomohide*; Sugiyama, Masaaki*; Inoue, Rintaro*; Tominaga, Taiki*
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The neutron associate elastic scattering device installed in large strength pulse neutron J-PARC is effective for the analysis of the protein dynamics of the pico second - nanosecond. It will show the importance of the QENS experiment of the protein using J-PARC to clarify how the dynamics of the space scale are related with cooperative dynamics of the whole protein affecting creature function expression then. On the other hand, for the structural biology to discuss a function based on a tertiary structure, it is difficult to relate a function to structure dynamics only from QENS spectrum. It is effective to quote molecular simulation so that structure discusses the information of dynamics to relate a function to structure scientifically. I suggest that I visualize the hierarchical structure of protein dynamics in atom resolving power by the MD-Neutron method which fused by a neutron dispersion experiment and molecules simulation while utilizing various technique of the structural biology in this announcement from different angles. In addition, about MurD which is multi-domain protein, I discuss a function of the protein from the dynamic structure that a couple did between the hierarchies of the scale between the different space-time.
Shamoto, Shinichi; Matsuura, Masato*; Akatsu, Mitsuhiro*; Ito, Takashi; Ieda, Junichi; Endo, Hitoshi*; Oda, Tatsuro*; Chang, L.-J.*; Nemoto, Yuichi*; Shibata, Kaoru
no journal, ,
no abstracts in English
Kumada, Takayuki; Akutsu, Kazuhiro*; Kawamura, Yukihiko*; Morikawa, Toshiaki*; Sahara, Masae*; Suzuki, Junichi*; Torikai, Naoya*
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We developed a technique of spin-contrast-variation neutron reflectometry (SCV-NR). Polarized-neutron reflectivity curves of a styrene homopolymer film vary as a function of their proton-polarization, P
, coherently with what expected when the films are homogeneously polarized. This result ensures that the SCV-NR curves are not deformed by inhomogeneous P in the film, but determine the structures of surfaces and interfaces properly. Conventional unpolarized neutron reflectivity UNR and negatively-polarized SCV-NR curves of poly(styrene-block-isoprene) (PSPI) films are reproduced by the model that the film has a flat free surface, but positively-polarized SCV-NR curves are not. We found from the global fit that the holes with the depth corresponding to one period of periodic lamellae are produced on the free surface of the PSPI films, whose reflection is hidden by strong one from the PSPI-Si interface in the UNR and negatively-polarized SCV-NR curves.
Oikawa, Kenichi; Harada, Masahide; Oi, Motoki; Sakai, Kenji; Oku, Takayuki; Kai, Tetsuya; Shinohara, Takenao
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no abstracts in English
Motokawa, Ryuhei; Kaneko, Koji; Nagai, Takayuki; Okamoto, Yoshihiro
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no abstracts in English
Harada, Masahide; Kogawa, Hiroyuki; Naoe, Takashi; Wakui, Takashi; Haga, Katsuhiro; Meigo, Shinichiro; Oi, Motoki; Takada, Hiroshi
no journal, ,
At spallation neutron source in J-PARC, 3 GeV and 1 MW proton beam hits into the mercury target and neutron beam is provided to neutron instruments. Changes of proton beam shape and position affect the structural integrity of the mercury target container and the neutron intensity providing to the neutron instruments. In the study, from the viewpoint of neutronics, changes of nuclear heat and neutron intensity were measured as the shape and the position of the proton beam were changed. The neutron intensity was measured with time-of-flight method using a He-3 counter at the neutron instrument, NOBORU. The nuclear heat was derived from the temperature rise rate of the thermocouple installed in the target container. The neutron intensity and nuclear heat were measured in each case of the proton beam condition. As a result of a comparison of the calculated value using the particle transportation calculation code (MCNPX and PHITS) with the measured one, it is in good agreement.
Mamiya, Hiroaki*; Oba, Yojiro; Terada, Noriki*; Hiroi, Kosuke; Shinohara, Takenao; Oikawa, Kenichi
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no abstracts in English
Osakabe, Toyotaka; Munakata, Koji*; Ishii, Yuta*; Kimura, Hiroyuki*; Yamauchi, Hiroki
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no abstracts in English
Kaneko, Koji; Frontzek, M. D.*; Matsuda, Masaaki*; Nakao, Akiko*; Munakata, Koji*; Ohara, Takashi; Kakihana, Masashi*; Haga, Yoshinori; Hedo, Masato*; Nakama, Takao*; et al.
no journal, ,
no abstracts in English
Kodama, Katsuaki; Honda, Takashi*; Ikeda, Kazutaka*; Shamoto, Shinichi; Otomo, Toshiya*
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no abstracts in English
Sakai, Kenji; Oi, Motoki; Haga, Katsuhiro; Takada, Hiroshi; Kai, Tetsuya; Nakatani, Takeshi; Kobayashi, Yasuo*; Watanabe, Akihiko*
no journal, ,
For safely and efficiently operating a spallation neutron source and a muon target, a general control system (GCS) operates within Materials and Life Science Experimental Facility (MLF). GCS consists of several subsystems such as an integral control system (ICS), interlock systems (ILS), shared servers, network system, and timing distribution system (TDS). Although GCS is an independent system that controls the target stations, it works closely with the control systems of the accelerators and other facilities in J-PARC. Since the first beam injection in 2008, GCS has operated stably without any serious troubles after modification based on commissioning for operation and control of MLF. Then, significant improvements in GCS were proceeded until 2015 in considering sustainable long-term operation and maintenance. In recent years, many instruments in GCS have replaced to next generation models due to end of production and support of them. This report summarizes upgrade history of GCS during a period of approximately ten years after start of beam operation, and its present status. As future plan, it will also discuss development of an abnormality sign determination system that can detects potential abnormality from slight state transitions of target stations by analyzing operation data over the entire MLF.
Nakamura, Tatsuya; To, Kentaro; Tsutsui, Noriaki; Sakasai, Kaoru
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We have developed various types of two-dimensional scintillation neutron detectors for neutron scattering instruments in the J-PARC MLF. Particularly the detector type using neutron-sensitive scintillation screen coupled with wavelength-shifting fibers has great flexibility in detector design, and they have been successfully employed for the beamline detectors. In this paper present status of the new detector development including 100-um spatial resolution imager, BIX-P2 detector will be presented.
Harjo, S.; Oikawa, Kenichi; Pham, A.*; Morito, Shigekazu*; Kawasaki, Takuro
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no abstracts in English
He spin filter in JAEAOkudaira, Takuya; Oku, Takayuki; Sakai, Kenji; Ino, Takashi*; Hayashida, Hirotoshi*; Hiroi, Kosuke; Shinohara, Takenao; Kakurai, Kazuhisa*; Aizawa, Kazuya
no journal, ,
He spin filter is a neutron polarization device composed of polarized He gas and alkali metal encapsulated into a special glass cell. Since a neutron absorption cross section of He has very large spin dependence, a polarized neutron beam for a wide energy range can be obtained passing through the polarized He gas. He nuclei are polarized irradiating a circularly polarized laser, which is referred to as Spin Exchange Optical Pumping method. The development of the He spin filter is ongoing in JAEA. Recently a spin flip technique of He using frequency sweep NMR and a measurement system of He polarization using electron paramagnetic resonance were developed. Additionally, a vacuum system to make He spin filter is also constructed.
Shibata, Kaoru
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hydrogen embrittlement observation of textured high strength steel using neutron diffractionXu, P. G.; Ishijima, Yasuhiro; Qiu, H.*; Morooka, Satoshi; Harjo, S.
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Sano, Asami; Hattori, Takanori; Komatsu, Kazuki*; Kagi, Hiroyuki*; Nagai, Takaya*
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Hydrogen exists not only on the Earth's surface as liquid water but also incorporated into minerals in the deep mantle as hydroxyl ion. At ambient pressure on the surface of the Earth, hydrogen in minerals generally takes an asymmetric position between two oxygen atoms, which forms a short covalent bond on the one side and a long and relatively weak hydrogen bond on the other side. However, it was theoretically predicted in 1970' that the hydrogen in ice locates at the center between two oxygen atoms under high pressure, which is so-called symmetrization of hydrogen bond. To investigate how the symmetrization affects on the physical properties of minerals, we conducted neutron diffraction experiments on 
-AlOOH at high pressure. We observed that hydrogen reaches at the center between two oxygen atoms at 18.1 GPa. The present study revealed that even small change of hydrogen atomic position but the symmetrization can change the physical property of mineral.
Seki, Yoshichika; Shinohara, Takenao; Parker, J. D.*; Matsumoto, Yoshihiro*; Hino, Masahiro*; Samoto, Tetsuo*; Yashiro, Wataru*; Momose, Atsushi*
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no abstracts in English