K/Ar ages of successive lava flows from the Deccan Traps,India     

Ichiro Kaneoka  Hiroshi Haramura 《Earth and Planetary Science Letters》1973,18(2):229-236

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Phase velocity and Q of mantle Rayleigh waves   总被引：1，自引：0，他引：1  

Ichiro Nakanishi 《Geophysical Journal International》1979,58(1):35-59

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Acceptance of the 2003 Geochemical Society of Japan Award     

Ichiro Kaneoka 《Geochimica et cosmochimica acta》2004,68(9):1973-1974

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A 100 m laser strainmeter system installed in a 1 km deep tunnel at Kamioka, Gifu, Japan   总被引：1，自引：0，他引：1  

Shuzo Takemoto  Akito Araya  Junpei Akamatsu  Wataru Morii  Hideo Momose  Masatake Ohashi  Ichiro Kawasaki  Toshihiro Higashi  Yoichi Fukuda  Shinji Miyoki  Takashi Uchiyama  Daisuke Tatsumi  Hideo Hanada  Isao Naito  Souichi Telada  Nobuo Ichikawa  Kensuke Onoue  Yasuo Wada 《Journal of Geodynamics》2004,38(3-5):477

We have installed a laser strainmeter system in a deep tunnel about 1,000 m below the ground surface at Kamioka, Gifu, Japan. The system consists of three types of independent interferometers: (1) an EW linear strainmeter of the Michelson type with unequal arms, (2) an NS-EW differential strainmeter of the Michelson type with equal arms and (3) a NS absolute strainmeter of the Fabry–Perot type. These are configured in L-shaped vacuum pipes, each of which has a length of 100 m. (1) and (2) are highly sensitive (order of 10⁻¹³ strain) and have wide dynamical range (10⁻¹³–10⁻⁶). Observations with strainmeters (1) and (2) started on June 11, 2003. (3) is a new device for absolute-length measurements of the order of 10⁻⁹ of a long-baseline (100 m) Fabry–Perot cavity by the use of phase-modulated light. This third strainmeter will be ready for operation before the end of 2004. The laser source of strainmeters (1) and (2) is a frequency-doubled YAG laser with a wavelength of 532 nm. The laser frequency is locked onto an iodine absorption line and a stability of 2 × 10⁻¹³ is attained. The light paths of the laser strainmeter system are enclosed in SUS304 stainless steel pipes. The inside pressure is kept to be 10⁻⁴ Pa. Consequently, quantitative measurement of crustal strains of the order of 10⁻¹³ can be attained by employing the laser strainmeter system of (1) and (2) at Kamioka. This resolving power corresponds to that of a superconducting gravimeter. Using the laser strainmeter system, we expect to determine parameters related to fluid core resonance, core modes and core undertone as well as other geodynamic signals such as slow strain changes caused by silent earthquakes or slow earthquakes.  相似文献   

In-situ investigation on growth and dissolution of crystals in aqueous solution     

Ichiro Sunagawa 《Aquatic Sciences - Research Across Boundaries》1993,55(4):347-357

In-situ observation methods to investigate the physics involved in growth and dissolution processes of crystals in aqueous solution at ordinary temperature and pressure are described. The methods visualize insitu the phenomena relating to clustering of nanometer sized embryonic particles, the mass transport from bulk solution and from a crystal, the concentration gradient in the diffusion boundary layer and its distribution around a crystal, and spiral growth steps with height of one nanometer. The techniques measure at the nanometer scale the growth and dissolution rates of individual spiral growth hillocks and etch pits whose dislocation characters are identified in-situ.  相似文献   

On the sensitivity characteristics of Lacoste & Romberg gravimeter (model G)     

Ichiro Nakagawa  Sinzi Nakai  Ryūichi Shichi  Hirokazu Tajima  Sadakatu Izutuya  Yoshiteru Kono  Toshihiro Higashi  Hiromi Fujimoto  Makoto Murakami  Kazuo Tajima  Minoru Funaki 《Journal of Geodesy》1985,59(1):55-67

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Spectral similarity between scalars at very low frequencies in the unstable atmospheric surface layer over the Tibetan plateau   总被引：1，自引：7，他引：1  

Jun Asanuma  Ichiro Tamagawa  Hirohiko Ishikawa  Yaoming Ma  Taiichi Hayashi  Yongqiang Qi  Jiemin Wang 《Boundary-Layer Meteorology》2007,122(1):85-103

Similarity between temperature and water vapour was investigated in the Fourier domain by using their coherency spectra, defined as the correlation coefficient between their Fourier modes, and the relative efficiency of their vertical transport. The class-averaged values of these indices were computed from the turbulence measurements over sparse grasslands on the Tibetan plateau during the intensive observations of GEWEX (Global Energy and Water Experiment) Asian Monsoon Experiment (GAME). It was found that the energy-containing eddies at scales up to 100z (z being height) are characterised by well-maintained similarity between these scalars. The scalars are highly correlated with each other, and their transport efficiencies are almost equal within this scale range. In contrast, similarity was not always maintained at scales larger than 1000z. Detailed analyses showed that this breakdown of similarity occurs occasionally or sporadically, suggesting that it is caused by events whose average return period is not much smaller than the current averaging time, i.e. 30 min. We speculate that entrainment of drier and warmer air at the top of the atmospheric boundary layer caused the scalar dissimilarity at this scale range.  相似文献   

Intergranular trace elements in mantle xenoliths from Russian Far East: Example for mantle metasomatism by hydrous melt     

Junji  Yamamoto  Shun'ichi  Nakai  Koshi  Nishimura  Ichiro  Kaneoka  Hiroyuki  Kagi  Keiko  Sato  Tasuku  Okumura  Vladimir S.  Prikhod'ko  Shoji  Arai 《Island Arc》2009,18(1):225-241

Based on both major and trace element chemistry, the occurrence of the intergranular component in mantle-derived xenoliths from far eastern Russia has been constrained. Whole-rock trace element measurements of one xenolith show apparent negative anomalies in Ce, Th, and high field strength elements on normalized trace element patterns. The trace element pattern of the whole rock differs from those of constituent minerals, indicating that the anomalies in the whole rock are attributable to the presence of an intergranular component. That assumption was confirmed using in situ analysis of trace elements in the intergranular substance and melt inclusion using laser ablation inductively coupled plasma–mass spectrometry. Both the intergranular component and the melt inclusions have identical trace element patterns, which mean that these materials are a cognate metasomatizing agent. The anomalies are regarded as mantle metasomatism related to an aqueous fluid. Hydrous minerals were observed on the wall of the melt inclusions using micro-Raman spectroscopy, indicating that the melt inclusions contained a large amount of water. Thus, this study reveals a trace element composition of a hydrous metasomatizing agent in the mantle.  相似文献   

Regional variations in trace element concentrations in tissues of black tiger shrimp Penaeus monodon (Decapoda: Penaeidae) from South Vietnam     

Tu NP  Ha NN  Ikemoto T  Tuyen BC  Tanabe S  Takeuchi I 《Marine pollution bulletin》2008,57(6-12):858-866

The goal of the present study was to examine the specific bioaccumulation of 22 trace elements in muscle, exoskeleton and hepatopancreas of black tiger shrimp Penaeus monodon from the Mekong River Delta (MRD), and the South Key Economic Zone (SKEZ), South Vietnam. The general tendency in most trace element concentrations among different tissues were hepatopancreas>exoskeleton>muscle. Comparisons of trace element levels in tissues between the two regions showed that concentrations of Se in muscle and As in all three tissues were higher in SKEZ; whereas in MRD, the higher concentrations of most elements such as Mn, Cu, Cd, Ba, Hg, were observed in tissues. These geographical variations in trace element levels may reflect the differences in human activities between the two regions of South Vietnam. The target hazard quotient (THQ) values for trace elements (<1) indicate that local residents are not exposed to potential health risks via the consumption of shrimp.  相似文献   

Regional variations in trace element concentrations in tissues of black tiger shrimp Penaeus monodon (Decapoda: Penaeidae) from South Vietnam     

Nguyen Phuc Cam Tu  Nguyen Ngoc Ha  Tokutaka Ikemoto  Bui Cach Tuyen  Shinsuke Tanabe  Ichiro Takeuchi   《Marine pollution bulletin》2008,57(6-12):858

The goal of the present study was to examine the specific bioaccumulation of 22 trace elements in muscle, exoskeleton and hepatopancreas of black tiger shrimp Penaeus monodon from the Mekong River Delta (MRD), and the South Key Economic Zone (SKEZ), South Vietnam. The general tendency in most trace element concentrations among different tissues were hepatopancreas > exoskeleton > muscle. Comparisons of trace element levels in tissues between the two regions showed that concentrations of Se in muscle and As in all three tissues were higher in SKEZ; whereas in MRD, the higher concentrations of most elements such as Mn, Cu, Cd, Ba, Hg, were observed in tissues. These geographical variations in trace element levels may reflect the differences in human activities between the two regions of South Vietnam. The target hazard quotient (THQ) values for trace elements (<1) indicate that local residents are not exposed to potential health risks via the consumption of shrimp.  相似文献