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31.
The three-dimensional subsurface structure model around Kansai International Airport (KIX) has been developed based on the geologically and geotechnically investigated results of a large amount of borehole data for estimation of subsidence. The model consists of the alternation of marine clay and coarse deposits. The many seismic surveys and borehole drillings were carried out around the KIX before the constructing the airport. The stratigraphy of the model was renewed by the KIX18-1, which was about 1,300 m long drilling core and was drilled near the 2nd runway of the KIX from 2006 to 2007. In this study, the subsurface geological model was revised by integration of renewed borehole data and seismic profiles to incorporate complex warping structure and heterogenic lateral variation.  相似文献   
32.
We monitored seasonal changes of the abundance and composition of microorganisms in the fish-farm sediment in Kusuura Bay, Amakusa, Japan, using the quinone profiling technique, during bioremediation by introducing cultured colonies of polychaete, Capitella sp. I. In November 2004, approximately 9.2 million cultured worms were transferred to the fish-farm sediment, which increased rapidly, and reached 458.5 gWW/m(2) (528,000 indiv./m(2)) in March 2005. During this fast-increasing period of Capitella, the microbial quinone content of the surface sediment (0-2 cm) also increased markedly, and reached 237 micromol/m(2) in January 2005, although the water temperature decreased to the lowest levels in the year. Particularly, the mole fraction of ubiquinone-10 in total quinones in the sediment, indicating the presence of alpha subclass of Proteobacteria, increased by 9.3%. These facts suggest that the bacterial growth was enhanced markedly by the biological activities of worms in the sediment, and the bacteria played an important role in the decomposition of the organic matter in the sediment.  相似文献   
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A logN — logS relation at 10 GHz is constructed for sources with the flat spectra 0.5 (flux densitySv ) from observations at NRO, MPIfR and others. Based on the source distribution on log (Luminosity) volume plane we obtain an epoch-depending luminosity function which explains the above relation.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984.Nobeyama Radio Observatory, a branch of the Tokyo Astronomical Observatory, University of Tokyo, is a facility open for general use by researchers in the field of astronomy and astrophysics.  相似文献   
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Using ichthyoplankton samples collected in the Kuroshio Subgyre during early summer cruises, we examined spatial distributions of scyllarid phyllosoma larvae in the Subgyre, particularly of the genus Scyllarus. The present study has two objectives: (1) to reveal species composition of Scyllarus phyllosoma larvae in the Kuroshio Subgyre, and (2) to examine larval recruitment of Scyllarus species as contrasted with that of Panulirus, particularly P. japonicus, the larval recruitment of which has been examined in detail. A total of 218 phyllosoma larvae collected in the present study belonged to two families (Palinuridae and Scyllaridae) representing 5 genera and 11 species. Phyllosoma larvae of two Scyllarus species (S. cultrifer and Scyllarus sp. c) were abundant among the collected larvae, and were found mainly in the following three regions located within the Kuroshio-Counter Current region south of Kuroshio Current: the water east of Okinawa Is., the water far east of Okinawa Is. (or far south of Shikoku Is.), and the water around Hachijojima Is. Larvae of each of the above two Scyllarus species collected in the three regions may belong to different populations: larvae collected in the water around Hachijojima Is. may come from their benthic populations along the Pacific coast of Honshu and Shikoku Is., central Japan, while larvae collected in the other two regions may come from their benthic populations of the Ryukyu Archipelago and Taiwan. Judging from their shorter larval period and current systems within the Kuroshio Subgyre, these Scyllarus larvae may be destined for death. An erratum to this article is available at .  相似文献   
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The δ18O, δ13C and trace element composition of pearls collected from Ago Bay, Japan, were investigated in order to evaluate biomineralization in the cultured pearl oyster (Pinctada fucata martensii). The oxygen isotopic data suggest that the pearls were produced around 23–24°C, mainly in June to early July, which is consistent with their occurrence in the field. Therefore the pearls were produced under or close to isotopic equilibrium conditions, although they showed high calcification rates (higher than 0.2–1.0 g cm− 2yr−1) under which, for example, coral skeletons (calcification rate ∼0.28 g cm− 2yr−1) often show non-equilibrium isotope partitioning. The δ13C values were ∼− 2.9‰ lower than those calculated for offshore waters under equilibrium conditions. This may be due to low-δ13C bottom waters resulting from the degradation of organic matter (OM) or to a contribution of low-δ 13C food. In the latter case, a simple mass balance calculation gives a respiration component of 14%. Twelve trace elements of bulk pearl samples were classified into four groups on the basis of their enrichment/depletion patterns relative to seawater and inter-element relationships: group 1, Co, Cr, Pb; group 2, Ba, Cs, U; group 3, Cu, Sn, V, and group 4, Mn, Rb, Mo. Comparison with coral skeletons suggests that Ba and Mn (groups 2 and 4) were definitely much enriched in proteinaceous OM relative to aragonite crystals in pearls and that V (group 3) in pearls showed only slight enrichment in the organicrich layer. By contrast, the other elements showed small differences between both layers (enrichment factor of <3), suggesting that these elements occur largely in aragonite crystals.  相似文献   
40.
Sedimentation processes of suspended matter supplied from the Huanghe (Yellow River) and the Changjiang are investigated with the use of a three-dimensional numerical model of the Yellow Sea and the East China Sea which includes the tidal current, residual flow and wind waves. Suspended matter supplied from the Huanghe mainly deposits in the Bohai Sea and that from the old river mouth of the Huanghe and from the Changjiang in the central part of the Yellow Sea or south of Cheju Island. The calculated results well reproduce the observed sedimentation pattern qualitatively except for the offshore area of the southeastern coast of China.  相似文献   
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