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191.
Munetake Sasaki Koichiro Fujimoto Hitoshi Tsukamoto Takayuki Sawaki Masakatsu Sasada Masanori Kurosawa Masahiko Yagi Yoichi Muramatsu Osamu Kato + Ryo Komatsu + Kaichiro Kasai + Nobuo Doi+ 《Resource Geology》2003,53(2):127-142
Abstract. Cathodoluminescence (CL) color, rare earth element (REE) content, sulfur and oxygen isotopes and fluid inclusions of anhydrite, which frequently filled in hydrothermal veins in the Kakkonda geothermal system, were investigated to elucidate the spatial, temporal and genetical evolution of fluids in the deep reservoir. The anhydrite samples studied are classified into four types based on CL colors and REE contents: type-N (no color), type-G (green color), type-T (tan color) and type-S (tan color with a high REE content). In the shallow reservoir, only type-N anhydrite is observed. In the deep reservoir, type-G anhydrite occurs in vertical veins whereas type-T and -N in lateral veins. Type-S anhydrite occurs in the heat-source Kakkonda Granite. The CL textures revealed that type-G anhydrite deposited earlier than type-T in the deep reservoir, implying that fracture system was changed from predominantly vertical to lateral.
Studies of fluid inclusions and δ34 S and δ18 O values of the samples indicate that type-N anhydrite deposited from diluted fluids derived from meteoric water, whereas type-G, -T and -S anhydrites deposited from magmatic brines derived from the Kakkonda Granite with the exception of some of type-G with recrystallization texture and no primary fluid inclusion, which deposited from fossil seawater preserved in the sedimentary rocks. Type-G, -T and -S anhydrites exhibit remarkably different chondrite-normalized REE patterns with a positive Eu anomaly, with a convex shape (peak at Sm or Eu) and with a negative Eu anomaly, respectively. The difference in the patterns might result from the different extent of hydrothermal alteration of the reservoir rocks and contribution of the magmatic fluids. 相似文献
Studies of fluid inclusions and δ
192.
中川地区一次负地闪的起始过程研究 总被引:14,自引:7,他引:7
利用GPS同步的多点慢天线电场变化仪在甘肃中川地雷暴过程中测量得到的资料,对一次负地闪的起始过程进行了分析。发现地闪产和在击发之前常有持续170-300ms的去2内放电过程发生,它可有数据不等的K变化组成。 相似文献
193.
Masayoshi Nakano Kazunari Fujii Shozaburo Takeuchi 《Pure and Applied Geophysics》1988,128(1-2):119-132
Theoretical calculations were performed on reflected and transmitted Rayleigh waves and scattered body waves, in the case where a two-dimensional Rayleigh wave is incident to a wedge-shaped medium having a wedge angle between 250° and 290° and arbitrary value of Poisson ratio. The reflection and transmission coefficients of Rayleigh waves were also experimentally measured in cases of wedges with 190° to 330° wedge angles. The method of theoretical analysis and the techniques of experiment are based on those developed in our preceding research (W-1. W-2 and W-3). Compared with the results where the wedge angle is smaller than 180° (W-1 and W-2), all features show consistent variation with wedge angle. 相似文献
194.
195.
Dredged spoil (DS) was used as a silt and clay additive in the construction of artificial tidal flats from mountain sand (MS). As the ratio of DS in the sediment media increased, the number of emerging macrobenthos increased. The composition of the macrobenthic community was also affected by the addition of DS, and the changes might be dependent on the ratio of DS to MS. In addition, the macrobenthos in the artificial tidal flats was more abundant than that in the control tidal flat, which was constructed with natural tidal flat sediment. With a silt and clay content of 25%, polychaetes Ceratonereis erythraeensis and Capitella sp. and the gastropod Batillaria cumingii were dominant, whereas no bivalves were present. With less silt and clay (5% and 10%), the bivalves Ruditapes philippinarum and Musculista senhousia were observed in the artificial flats, while their numbers in the control tidal flat were lower. 相似文献
196.
197.
Ze‐Hua Liu Takeshi Hashimoto Yoichi Okumura Yoshinori Kanjo Satoshi Mizutani 《洁净——土壤、空气、水》2010,38(2):181-188
A solid‐phase extraction (SPE)‐gas chromatography (GC)‐mass spectrometry (MS) analytical method was developed for the simultaneous analysis of natural free estrogens and their conjugates in wastewater samples. Natural free estrogens and their conjugates in wastewater were successfully separated by the oasis hydrophilic‐lipophilic balance solid phase extraction (Oasis HLB SPE) method, and the conjugates were initially enzyme hydrolyzed by β‐glucuronidase or arylsulfatase from Helix pomatia prior to derivatization. N‐methyl‐N‐(tert‐butyldimethylsilyl)trifluoroacetamide (MTBSTFA) plus 1% tert‐butyldimetheylchlorosilane (TBDMCS) was chosen as the derivatization reagent, and the most appropriate conditions of derivatization were determined to be at 95°C for 90 min. The recovery ratios of nine target chemicals were determined by spiking them in 1 L of ultra‐purified water or the influent of a wastewater treatment plant (WWTP). The recovery ratios of six out of nine for the analytes ranged from 73.3–114.9% with relative standard deviations (RSD) from 1.6–19.9%. The established method was successfully applied to environmental wastewater samples which were collected from one municipal wastewater treatment plant (WWTP) in Osaka, Japan, for the determination of natural free estrogens and their conjugates. In the influent sample, E1, E2, E1‐3S, E3‐3S, and E1‐3G were detected at concentrations of 16.6, 9.6, 8.2, 21.9, and 3.2 ng L–1, respectively. However, only E1 was detected at a high concentration of 44 ng L–1 in the effluent sample, suggesting that it is the dominant natural free estrogen in the effluent. 相似文献
198.
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
199.
Suhardja D. Wiramihardja Tomokazu Kogure Makoto Nakano Shigeomi Yoshida Ken'Ichi Tatematsu 《Astrophysics and Space Science》1986,118(1-2):311-315
A survey of emission-line stars was carried out in the CMa star formation region, based on spectral observations with the Kiso Schmidt telescope. In total, 128 emission-line stars were detected, ranging fromV=6 to 15, and the majority are found withV between 11 and 14. A comparison with the existing catalogues shows that some emission-line stars are common with ours, while some exhibit no detectable emission line on our plates, suggesting the variability of emission-line strength. The two-colour (U–B, B–V) diagram is also shown for the detected stars.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
200.
Anil Bhardwaj Stas Barabash Yoshifumi Futaana Yoichi Kazama Kazushi Asamura David McCann R. Sridharan Mats Holmstrom Peter Wurz Rickard Lundin 《Journal of Earth System Science》2005,114(6):749-760
This paper reports on the Sub-keV Atom Reflecting Analyzer (SARA) experiment that will be flown on the first Indian lunar
mission Chandrayaan-1. The SARA is a low energy neutral atom (LENA) imaging mass spectrometer, which will perform remote sensing
of the lunar surface via detection of neutral atoms in the energy range from 10 eV to 3 keV from a 100km polar orbit. In this
report we present the basic design of the SARA experiment and discuss various scientific issues that will be addressed. The
SARA instrument consists of three major subsystems: a LENA sensor (CENA), a solar wind monitor (SWIM), and a digital processing
unit (DPU). SARA will be used to image the solar wind-surface interaction to study primarily the surface composition and surface
magnetic anomalies and associated mini-magnetospheres. Studies of lunar exosphere sources and space weathering on the Moon
will also be attempted. SARA is the first LENA imaging mass spectrometer of its kind to be flown on a space mission. A replica
of SARA is planned to fly to Mercury onboard the BepiColombo mission. 相似文献