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161.
S. Yoshida M. Nakano T. Kogure T. Sasaki S. D. Wiramihardja S. Mizuno K. Sakka 《Astrophysics and Space Science》1986,119(1):131-133
We have carried out surface photometry of six simpleHii regions which are characterized by the existence of an exciting star earlier than B0, and a nearly round shape. On the basis of on balibrated image data and adopting a spherical model, we derive the distributions of gas and dust densities in theHii regions.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984.On leave from the Bosscha Observatory, Institute of Technology Bandung, Indonesia. 相似文献
162.
Sulfur isotopic composition of the magnetite-series and ilmenite-series granitoids in Japan 总被引:1,自引:0,他引:1
Sulfur isotopic composition has been measured on 30 granitoids and 11 gabbroids from the Cretaceous and Tertiary granitic terranes of Japan. The two series of granitoids, the magnetite-series and ilmenite-series, defined by Ishihara (1977), show two specific isotope trends. The magnetite-series granioids all have positive (su34)S (CDT) values from +1 to +9, while the ilmenite-series rocks are dominated by negative values between –11 and –1. The trend in the ilmenite-series is consistent with the thesis that the magma has been influenced by light biogenic sulfur from the continental crust. The inferred large scale magma-crust interaction in the ilmenite-series granitoids indicates that the emplacement of this series of magma has been governed by a stoping mechanism.In contrast, the magnetite-series granitoids have little if any evidence for significant magma-crust interaction, indicating that the intrusion of this series of magma may have been more or less of fissure-filling type. Their trend towards positive (su3 4)S values (average +5) argues for the introduction of some heavy sulfur, probably of seawater origin, into the mantle derived sulfur. This is most likely to occur in an arctrench system by the subduction of an oceanic plate which accompanies the sulfate-bearing pelagic sediments.The isotopic data of gabbroids, mostly between –1 and +3, are close to the commonly assumed value for mantle sulfur. Nevertheless, the gabbroids from the magnetite-series granitic terranes tend to have higher (su34)S value than those from the ilmenite-series belts. It is inferred that the factors controlling the isotope characteristics of the granitoid sulfur have also been operative in these grabbroids at least to some extent. 相似文献
163.
Konishi Hisahiro Manabu Kato Susumu Sasaki Yoshisada Takizawa Hitoshi Mizutani 《Journal of Earth System Science》2005,114(6):771-775
SELENE (Selenological and Engineering Explorer) project started as a joint mission of the former ISAS (Institute of Space
and Astronautical Science) and the former NASDA (National Space Development Agency: the two organizations were merged into
JAXA in 2002) of Japan in 1998. The launch target is rescheduled for 2006 due to delay of completion of launch vehicle, H-IIA.
The SELENE project is now under a sustained design phase. The flight model components were manufactured, and the interface
tests between the bus-system and the mission instruments were completed by the end of March 2004. The functional checks and
calibration for the flight model components are being carried out at present. From the beginning of 2005, the final assembly
tests will start. 相似文献
164.
Observation of shear zone development in ring-shear apparatus with a transparent shear box 总被引:1,自引:1,他引:1
Using a new ring-shear apparatus with a transparent shear box and video image analysis system, drained and undrained speed-controlled tests were conducted on coarse-grained silica sands to study the shear-zone formation process in granular materials. Velocity distribution profiles of grains under shear at various stages in the ring shear tests were observed through processing the video image by the Particle Image Velocimetry (PIV) program. Shear-zone thickness and type of shear mode (slide-like or flow-like) during shear were observed. Before reaching peak strength in low-speed and drained condition test, a comparatively major part of the sample in the upper shear box showed a velocity distribution profile of structural deformation and dilatancy behavior. After peak strength, the velocity profile changed into a slide-like mode and thereafter showed almost no change. In higher speed tests with drained and undrained conditions, an almost slide-like mode was observed, compared to low-speed test. Apparent shear-zone thicknesses of high-speed tests are thinner than low-speed tests. Unexpectedly, almost no difference was observed in the shear-zone thickness and mode of shear (slide or flow-like) between drained and undrained tests. This study was conducted as part of the International Programme on Landslides (IPL) M101 “Areal prediction of earthquake and rain induced rapid and long-traveling flow phenomena (APERITIF)” of the International Consortium on Landslides (ICL). These results will contribute to understanding the mechanism of shear-zone development in granular materials as a basic knowledge for disaster risk mitigation of rapid long run-out landslides. 相似文献
165.
166.
Keiko Sasaki Yoshitaka Uejima Atsushi Sakamoto Qianqian Yu Junichiro Ishibashi Naoko Okibe Tsuyoshi Hirajima 《Resource Geology》2013,63(2):155-165
Microbiological contribution to the formation of the manganese deposits in Sambe hot springs, Shimane, was investigated in combination with water chemistry, characterization of sediments and microbial community structure. Analysis of bacterial and fungal community structure based on DNA extracted from a Mn‐oxidizing enrichment culture indicated close matches with Pseudomonas putida, Phoma sp. and Plectosphaerella cucumerina, all Mn‐oxidizing microorganisms. These sediments were poorly crystalline and formed at neutral pH values, which is characteristic of biogenic precipitates. The EPMA results demonstrated a positive correlation between Mn and Ba contents in well‐crystalline Mn oxide grains. Substantial Ba contents were observed inside Mn oxide grains. These findings indicated that Ba contents in sediments are influenced by not only aqueous Ba2+ concentrations but also crystallinity of biogenic birnessite. Barium would be incorporated in birnessite during biomineralization. 相似文献
167.
MPS方法数值模拟液舱晃荡问题 总被引:1,自引:0,他引:1
基于无网格粒子法MPS方法(moving particle semi-implicit method)研究了液舱晃荡问题。针对二维矩形液舱晃荡问题进行了数值验证,结果表明MPS方法能够很好地计算晃荡产生的拍击压力。同时将MPS方法应用到带隔板的液舱晃荡问题计算中,分析了二维和三维带隔板液舱晃荡问题。计算结果表明:隔板的存在很大程度地限制了流体的水平运动,隔板附近出现了自由面的翻卷、破碎和融合现象,MPS方法能够很好地模拟这些流动现象。计算得到的波高与实验测得的波高吻合较好,表明MPS方法模拟带隔板的晃荡问题具有一定的可靠性。 相似文献
168.
Recent noble gas data of mantle-derived samples show that there are two end members: PLUME-type and MORB-type. The estimated high 3He and 22Ne abundances of the PLUME source, possibly representing the lower mantle, should reflect the remnant of dissolved solar-type atmosphere. Calculations of the structure of the primary atmosphere and the noble gas dissolution into the magma ocean of the accreting planet suggest that the high 3He and 22Ne abundances can be explained if the primary atmosphere persisted until M0.4–0.6 ME (ME being the present Earth mass). The PLUME source has higher 3He/4He and lower 21Ne/22Ne than the MORB source. This is explained by assuming that the lower mantle was less degassed during magma ocean cooling. The carbon abundance in the mantle can be constrained from the estimated abundance of mantle 3He and C/3He data of the present mantle-derived samples. Dissolved solar-type noble gas might explain high noble gas abundance in the present Venus, if the primary atmosphere persisted until the final stage of accretion under lower dust opacity of the atmosphere. 相似文献