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101.
Precise determination of the partitioning of Mg and Fe2+ between olivine and ultramafic melt has been made at pressures from 5 to 13 GPa using a MA-8 type multi-anvil high-pressure apparatus (PREM) installed at Earthquake Research Institute, University of Tokyo. A very short rhenium capsule (<100 μm sample thickness) was adopted to minimize temperature variation within the sample container. Synthetic gels with the composition of the upper mantle peridotite were used as starting materials to promote the homogeneity. Analyses of quenched melts and coexisting olivines were made with an electron probe microanalyzer. The obtained partition coefficient, KD [=(FeO/MgO)ol/(FeO/MgO)melt], decreases from 0.35 to 0.25 with increasing pressure from 5 to 13 GPa, suggesting a negative correlation between pressure and KD above 5 GPa. Our result is consistent with a parabolic relationship between KD and degree of polymerization (NBO/T) of melts reported by previous studies at lower pressures. The negative correlation between pressure and KD suggests that olivine crystallizing in a magma ocean becomes more Mg-rich with depth and that primary magmas generated in the upper mantle become more Fe-rich with depth than previously estimated. 相似文献
102.
This paper presents a rational approach to the finite strain analysis of elastic-plastic materials. An updated incremental finite element technique was applied to problems of shallow foundations of homogeneous as well as multilayer soils. This was based on a variational principle which is suitable for such problems. 相似文献
103.
Literal characterizations are developed for the eigenvalues and eigenvectors of a system of linear time-invariant equations which describes the attitude motion of flexible spacecraft in terms of hybrid coordinates. The eigenproblem is shown to reduce to that of a symmetric and positive definite matrix of lower dimension. For the zero damping case, both analytical and minimax characterization methods prove to be useful in localizing the eigenvalues, and eigenvectors for systems of large dimension are obtained explicitly in terms of a 3×1 matrix whose elements are available from a system of three algebraic equations provided. 相似文献
104.
M. Matsuoka M. Fujii S. Miyamoto J. Nishimura M. Oda Y. Ogawara S. Hayakawa I. Kasahara F. Makino Y. Tanaka P. C. Agrawal B. V. Sreekantan 《Astrophysics and Space Science》1972,18(2):472-490
Simultaneous hard X-ray and optical observations of Sco X-1 were carried out on 1971 May 1 at Hyderabad, India, when Sco X-1 was optically bright. The X-ray intensity observed by balloon-borne counter telescopes increased in coincidence with optical enhancements, while the plasma temperature derived by fitting the X-ray spectrum in the energy range 20–40 keV to the thermal bremsstrahlung spectrum did not appreciably change over the whole period of observation. 相似文献
105.
M. Endo R. Fujii Y. Ogawa S. C. Buchert S. Nozawa S. Watanabe N. Yoshida 《Annales Geophysicae》2000,18(2):170-181
We have determined the MLT distribution and KpKP dependence of the ion upflow and downflow of the thermal bulk oxygen ion population based on a data analysis using the EISCAT VHF radar CP-7 data obtained at Tromsø during the period between 1990 and 1996: (1) both ion upflow and downflow events can be observed at any local time (MLT), irrespective of dayside and nightside, and under any magnetic disturbance level, irrespective of quiet and disturbed levels; (2) these upflow and downflow events are more frequently observed in the nightside than in the dayside; (3) the upflow events are more frequently observed than the downflow events at any local time except midnight and at any KP level and the difference of the occurrence frequencies between the upflow and downflow events is smaller around midnight; and (4) the occurrence frequencies of both the ion upflow and downflow events appear to increase with increasing KP level, while the occurrence frequency of the downflow appears to stop increasing at some KP level 相似文献
106.
Tsurane Kuragano Yosuke Fujii Takahiro Toyoda Norihisa Usui Koji Ogawa Masafumi Kamachi 《Journal of Oceanography》2014,70(1):45-62
A consistency between seasonal fluctuation of actual sea surface height (SSH) and those caused by mass and density variations in gyre-scale regions is examined. The SSH obtained from satellite altimetry (altimetric SSH) is adopted as the actual SSH. SSH caused by mass variation (mass-related SSH) is simulated using a barotropic global ocean model forced by water flux, wind stress and surface pressure. SSH caused by density variation (steric SSH) is calculated from water density profile, i.e. temperature and salinity profiles. The model SSH well represents mass-related SSH for gyre-scale regional means, and seasonal fluctuation of the altimetric SSH corrected for the model SSH is similar to that of steric SSH above a pressure level larger than 300 dbar. The results indicate that the mass-related SSH does not much respond to the baroclinic adjustment to the seasonally varying wind stress curl. The mass-related SSH forced by wind stress and surface pressure should be accounted for regional evaluation, though it is not necessary for global mean evaluation. Detection of steric SSH from altimetric SSH would be useful for assimilation approaches in which the altimetric SSH is treated as the variable reflecting subsurface temperature and salinity. 相似文献
107.
Hirofumi Hinata Satoshi Fujii Keita Furukawa Tomoya Kataoka Masafumi Miyata Takashi Kobayashi Masahiro Mizutani Takahiro Kokai Nobuyoshi Kanatsu 《Estuarine, Coastal and Shelf Science》2011
Signals from the tsunami waves induced by the March 11, 2011 moment magnitude (Mw) 9.0 Tohoku-Oki earthquake and from subsequent resonances were detected as radial velocity variability by a high-frequency ocean surface radar (HF radar) installed on the eastern coast of the Kii Channel, at a range of about 1000 km from the epicenter along the eastern to southern coasts of Honshu Island. A time–distance diagram of band-passed (9–200 min) radial velocity along the beam reveals that the tsunami waves propagated from the continental shelf slope to the inner channel as progressive waves for the first three waves, and then natural oscillations were excited by the waves; and that the direction of the tsunami wave propagation and the axis of the natural oscillations differed from that of the radar beam. In addition, spectral analyses of the radial velocities and sea surface heights obtained in the channel and on the continental shelf slope suggest complex natural oscillation modes excited by the tsunami waves. 相似文献
108.
Masayuki Uesugi Ryo Noguchi Tooru Matsumoto Junya Matsuno Takashi Nagano Akira Tsuchiyama Shigenori Harada Kaori Yokoyama Yoshiaki Yodo Noboru Takeda Toru Yada Shogo Yakame Yuzuru Karouji Yukihiro Ishibashi Masanao Abe Tatsuaki Okada Akio Fujimura Mitsuru Ebihara Fumio Kitajima Keisuke Nagao Tomoki Nakamura Hiroshi Naraoka Takaaki Noguchi Ryuji Okazaki Hisayoshi Yurimoto 《Meteoritics & planetary science》2014,49(7):1186-1201
We report the investigation of cutting methods for Hayabusa samples. The purpose of our study is to explore the possibility of applying multiple analyses to a single particle effectively. We investigated the cutting performance of a blade dicing saw, laser, focused ion beam (FIB), and physical breaking by microindenter. Cutting performance was examined by estimating the aspect ratio of the cut slit, i.e., depth over width of the slit. We also investigated the possible contamination and sample damage by cutting. The result of the investigation shows that we can cut the samples from <50 μm to 500 μm using those methods with aspect ratios from 10 to 20, although they would introduce some contamination or damage to the samples. Our investigations also provide an important basis for the analysis of samples obtained by future sample return missions. 相似文献
109.
A ring of compact radio continuum sources was found atl=24°.6b=0°.0, which we call the Scutum ring. Radio continuum,Hi line, and CO line observations are suggested that it is a star-forming region triggered by an expanding diffuseHii region.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984.NRO, a branch of the Tokyo Astronomical Observatory, University of Tokyo, is a cosmic radio observing facility open for outside users. 相似文献
110.
The relation between the size and velocity of impact crater ejecta has been studied by both laboratory experiments and numerical modeling. An alternative method, used here, is to analyze the record of past impact events, such as the distribution of secondary craters on planetary surfaces, as described by Vickery (Icarus 67 (1986) 224; Geophys. Res. Lett. 14 (1987) 726). We first applied the method to lunar images taken by the CLEMENTINE mission, which revealed that the size-velocity relations of ejecta from craters 32 and 40 km in diameter were similar to those derived by Vickery for a crater 39 km in diameter. Next, we studied the distribution of small craters in the vicinity of kilometer-sized craters on three images from the Mars Orbiter Camera (MOC) on board the Mars Global Surveyor (MGS). If these small craters are assumed to be secondaries ejected from the kilometer-sized crater in each image, the ejection velocities are of hundreds of meters per second. These data fill a gap between the previous results of Vickery and those of laboratory studies. 相似文献