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21.
Relationship Between Solidification Depth of Granitic Rocks and Formation of Hydrothermal Ore Deposits 总被引：14，自引：0，他引：14
Chemical analysis of biotite in representative granitic rocks in Japan shows that the total Al (TAl) content changes with the metal type of the accompanying hydrothermal ore deposits and increases in the following order: Pb‐Zn and Mo deposits < Cu‐Fe and Sn deposits < W deposits < non‐mineralized granitic rocks. The TAl content of biotite in granitic rocks may be a useful indicator for distinguishing between mineralized and non‐mineralized granitic rocks. A good positive correlation is seen between the TAl content of biotite and the solidification pressure of the granitic rocks estimated by sphalerite and hornblende geobarometers and the mineral assemblages of the surrounding rocks. These facts suggest that the TAl content of biotite can be used to estimate the solidification pressure (P) of the granitic rocks. The following empirical equation was obtained: where TAl designates the total Al content in biotite on the basis O = 22. According to the obtained biotite geobarometer, it is estimated that Pb‐Zn and Mo deposits were formed at pressures below 1 kb, Cu‐Fe and Sn deposits at 1–2 kb, W deposits at 2–3 kb and non‐mineralized granitic rocks were solidified at pressures above 3 kb. 相似文献
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Yi-Ming Hu Jin Chang Yi-Zhong Gong Ren-Jian Zhang Nan-Sen Wang He-Sen Tang S. Torii J. Nishimura T. Kobayashi Y. Shimizu F. Makino 《Chinese Astronomy and Astrophysics》2008
The emulsion chamber detector on board the “ShiJian-8” satellite is the first one in China designed especially for observing in space the highenergy electrons and γ-rays. In this paper, the principle of the detector design, the method of data processing and the preliminary results of observations are introduced. The design lifetime of the detector is 15 days on the orbit, and the energy range of detectable particles is 100GeV∼5TeV. 相似文献
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胡一鸣 常进 宫一忠 张仁健 王楠森 唐和森 Torii S. Nishimura J. Kobayashi T. Shimizu Y. Makino F. 《天文学报》2008,49(2):233-242
"实践八号"乳胶室探测器是我国首次用于空间观测高能电子及伽玛射线的乳胶 室探测器.介绍"实践八号"乳胶室探测器的设计原理、数据分析方法、设计过程和初步 观测结果等."实践八号"乳胶室探测器空间观测时间为15天,可探测的粒子能量范围为 100GeV～5TeV. 相似文献
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Holger Baumgardt Douglas C. Heggie Piet Hut Junichiro Makino 《Monthly notices of the Royal Astronomical Society》2003,341(1):247-250
This paper considers the phenomenon of deep core collapse in collisional stellar systems, with stars of equal mass. The collapse takes place on some multiple, ξ−1 , of the central relaxation time, and produces a density profile in which ρ∝ r −α , where α is a constant. The parameters α and ξ have usually been determined from simplified models, such as gas and Fokker–Planck models, often with the simplification of isotropy. Here we determine the parameters directly from N -body simulations carried out using the newly completed GRAPE-6. 相似文献
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Y. Fukada S. Hayakawa I. Kasahara F. Makino I. Suzuki Y. Tanaka B. V. Sreekantan 《Solar physics》1975,42(2):441-444
A hard solar X-ray burst in the energy range 90–400 keV was observed at about 0528:30 UT on 13 April 1974. This event is peculiar in the sense that the X-ray flux is considerably high whereas the corresponding radio and optical flares are of moderate sizes, that the duration of the X-ray burst is very short, and that the X-ray peak is delayed by about 2.5 min relative to the first radio peak. 相似文献
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Junichiro Makino Kazuhide Akiyama Daiichiro Sugimoto 《Astrophysics and Space Science》1991,185(1):63-78
Merger process of binary globular cluster is discussed for a pair of unequal-mass components. We calculated the case of mass ratio 10.5 by means of anN-body code with 6144 particles in total. We have found the followings. The mass exchange between the components takes place through the Roche-lobe overflow. In the early stages, however, the dynamical evolution is mainly governed by escape of particles from the system. As the particles escape carrying angular momentum with them, the separation between the component cluster shrinks. The time-scale of this shrinkage depends upon the size of the clusters. When a critical separation is reached, the orbital angular momentum is transferred unstably to the spins of the component clusters. This is the process of the synchronization instability which was found in a previous study on binary cluster of equal masses. As a result the component clusters merge into a single cluster. The structures of the mergers are quite similar among different cases except for the central cores which retain their initial central concentrations. In particular, the ellipticity and the rotation curve are quite close each other among models of different initial radii and of different mass ratios. 相似文献
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Internal microtextures of ternary alkali feldspars in sanidine trachyte from Oki-Dogo Island were examined using an electron microprobe analyzer, a scanning electron microscope, a transmission electron microscope and cathodoluminescence instruments, to develop the understanding of volcanic processes of alkaline magmas related to feldspar crystallization. The examined trachyte is an evolved rock of the Oki-Dogo Pliocene trachyte group. Its phenocryst feldspars are commonly associated with lamellar-wavy-domain textures with scales approximately from 100 nm up to several hundreds of μm that show complex and gradual variations in composition: however, anti-rapakivi zoning textures common in other Oki-Dogo alkaline rocks are almost completely absent in the trachyte. These textures are produced by extensive magmatic ion-exchange replacement reactions progressively advanced in the evolved magma. Characteristic braided fluorite alignments are developed consistently with lamellar-wavy-domain textures in phenocryst feldspars, and similar braided alignments are also present in groundmass feldspars with complicated microtextures. Most of fluorite grains are <100 nm in diameter, and the patterns of braided fluorite alignments vary greatly in individual feldspars. The whole occurrence of the feldspar microtextures represents an extreme example of diffusion-controlled replacement reactions, progressively advanced in the dry (relatively anhydrous) trachyte magma. The genetic processes forming fluorite alignments in feldspars are related to magma compositions, especially F and P contents, and the crystallization of F-bearing minerals, especially of fluorapatite. 相似文献
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A. Suda T. Makino 《International Journal of Environmental Science and Technology》2016,13(10):2375-2382
Rice consumption is considered an important arsenic source for the population in Asian countries. Previous studies showed increase in arsenic solubility in flooded soils and arsenic uptake by rice plants with the application of organic amendments, while contrasting results were also reported. Here, we comprehensively examined the effect of three types of organic amendments on arsenic solubility during long-term flooded soil incubation. The amendments examined were categorized as (1) plant-based composts, (2) cattle manures, and (3) fermented livestock (swine and poultry) droppings. The dissolved arsenic in all soils with fermented livestock dropping was significantly greater than that in control soils at 10 and 39 days after incubation. The soils with two cattle manures also contained significantly greater amounts of dissolved arsenic than control soils at day 39, while the rest of the amendments did not increase arsenic solubility. At day 80, the amount of dissolved arsenic in all soils became comparable. Tukey’s test demonstrated that the relative ratio of dissolved arsenic in soils with fermented livestock droppings to control soils was significantly greater than those with the plant-based composts and cattle manures at days 10 and 39. Furthermore, the solubilizing effect of some organic amendments was mostly explained by promotion of decrease in soil Eh, rather than increase in dissolved organic carbon. Thus, it could be concluded that fermented livestock droppings potentially have a greater risk of solubilizing As than plant-based composts and cattle manures, because of their greater ability for accelerating soil reduction, associated with their higher bio-decomposability. 相似文献