Iron-water reaction at high pressure and temperature, and hydrogen transport into the core     

Eiji Ohtani  Naohisa Hirao  Tadashi Kondo  Masayoshi Ito  Takumi Kikegawa 《Physics and Chemistry of Minerals》2005,32(1):77-82

We observed a direct reaction of metallic iron with water to form iron hydride and iron oxide, 3Fe + H₂O–>2FeH_x + FeO, at pressures from 6 GPa to 84 GPa and temperatures above 1,000 K in diamond anvil cell (DAC). Iron hydride is dhcpFeH_x or -FeH_x, and iron oxide has the rhombohedral or B1 structure at pressures at least up to 37 GPa. The formation of an assembly composed of dhcpFeH_x and FeO with the B8 structure was observed at 84 GPa. In primordial Earth, water formed by dehydration of the low temperature primitive materials reacts with metallic iron in the high temperature component to form iron hydride FeH_x and iron oxide FeO. The former would be incorporated in the iron forming the core. Thus hydrogen could be an important element of the Earths core. This reaction would be essential for transport of hydrogen into the core in the accretion stage of the Earth.  相似文献   

Shear-wave splitting observed above small earthquakes in a geothermal area of Japan     

Satoshi Kaneshima  Hisao Ito  Mitsuhiko Sugihara 《Geophysical Journal International》1988,94(3):399-411

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Large-Scale Translation of Accreted Terranes Along Continental Margins     

Shigeki Hada  Mitsumasa Ito  C.A. Landis  P.A. Cawood 《Gondwana Research》2001,4(4):628-629

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Multivariate analysis of trace elements in shallow groundwater in Fuchu in western Tokyo Metropolis,Japan     

Dang Quoc Thuyet  Hirotaka Saito  Takeshi Saito  Shigeoki Moritani  Yuji Kohgo  Toshiko Komatsu 《Environmental Earth Sciences》2016,75(7):559

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ISRM Suggested Methods for Determining the Creep Characteristics of Rock   总被引：4，自引：2，他引：2  

Ömer Aydan  Takashi Ito  Ugur Özbay  M. Kwasniewski  K. Shariar  T. Okuno  A. Özgenoğlu  D. F. Malan  T. Okada 《Rock Mechanics and Rock Engineering》2014,47(1):275-290

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Tropospheric delay correction with dense GPS network in L1-SAIF augmentation   总被引：2，自引：0，他引：2  

Noboru Takeichi  Takeyasu Sakai  Sounosuke Fukushima  Ken Ito 《GPS Solutions》2010,14(2):185-192

The L1-SAIF (L1 Submeter-class Augmentation with Integrity Function) signal is one of the Quasi-Zenith Satellite System (QZSS) navigation signals, which provides an augmentation function for mobile users in Japan. The tropospheric delay correction in the L1-SAIF augmentation is discussed in detail. Because the topographical features in Japan are complicated, the correction information is generated from GPS observation data collected at 200 GPS stations which are densely distributed over Japan. A total of 210 Tropospheric Grid Points (TGPs) are arranged to fully cover Japan. The TGPs that provide the correction information are selected adaptively to achieve the expected correction accuracy. This selection of TGPs is provided by the TGP mask message. Mobile users acquire the zenith tropospheric delay (ZTD) value at neighboring TGPs from the correction messages, and can estimate the local ZTD value accurately by using a suitable ZTD model. Only up to seven L1-SAIF messages are sufficient to provide the full correction information. Accuracy evaluations have proven that it is possible to achieve a correction accuracy of 13.4 mm RMS. The strategy presented here has been implemented into the augmentation system using the L1-SAIF signal, and its application guidance is presented in the QZSS interface specification.  相似文献