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71.
Magnesite, siderite and dolomite are characteristic alteration minerals occurring in Miocene hanging wall rocks of dacitic
composition which host the Kuroko orebodies. These carbonates generally occur in a more stratigraphically upper horizon than
chlorite alteration zone surrounding the orebodies. The Mg/(Mg+Fe) ratios of the carbonates decrease from the central alteration
zone to marginal zone. The Mg/(Mg+Fe) ratios of carbonates and chlorite positively correlate. The δ18O and δ13C values of magnesite, siderite and dolomite positively correlate with each other and lie between the igneous and marine carbonate
values. The petrographic, isotopic and fluid inclusion characteristics and thermochemical modelling calculations indicate
that magnesite and dolomite formed in the central zone close to the orebodies due to the interaction of hydrothermal solutions
with the biogenic marine carbonates. Calcite formed further from the orebodies from hydrothermal fluids which did not contain
a biogenic marine carbon component. The compositional and textural relationships indicate that superimposed alterations (chlorite
alteration and carbonate alteration) occurred in hanging wall rocks. The mode of occurrences and the Mg/(Mg+Fe) ratios of
magnesite and dolomite occurring in hanging wallrocks are useful in the exploration for concealed volcanogenic massive sulfide-sulfate
deposits.
Received: 9 September 1997 / Accepted: 23 September 1997 相似文献
72.
Minoru Umezu 《Astrophysics and Space Science》1998,259(4):343-354
We find that the hydrogen flux near the boundary of the semiconvection zone with Ledoux's neutral condition is unreasonably
positive while it is reasonably negative throughout the semiconvection zone with Schwarzschild's neutral condition.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
73.
Minoru Umezu 《Monthly notices of the Royal Astronomical Society》1998,298(1):193-206
The treatment of the overstable zone by Langer, Sugimoto &38; Fricke is extended so that the effects of radiative heat loss from convective elements and of the mixing length are included. As the overstability investigated by Kato arises because of the radiative heat loss from the convective element, this loss may play a role in the heat flux. In the formulation presented in this work, the diffusion coefficient depends on the mixing length when the mixing length is very small. In calculations with the method of Langer et al., the efficiency factor of the diffusion coefficient of chemical species is sometimes much smaller than 1. This exceedingly small efficiency factor may be explained by the dependence of the diffusion coefficient on the mixing length. We find that the neutral condition of Kato's overstable zone is ∇ rad = ∇ ad . 相似文献
74.
Edward D. Goldberg Minoru Koide Kathe Bertine Vern Hodge Martha Stallard Darko Martincic Nevenka Mikac Marco Branica Jamal K. Abaychi 《Applied Geochemistry》1988,3(6)
Inorganic surfaces sorb dissolved and particulate phases from seawater onto organic films from a variety of sources. Heavy metals such as Au, Pt, Mn and Cd come to the coatings primarily from particulate phases. This observation confirms a previous finding of this laboratory for the uptake of U, Pu and Po. With depth in the open ocean there are greater contributions from the dissolved phases. Microbial and photochemical processes can enrich surfaces in some metals through reduction reactions. Copper and Mn enrichments in the films are attributed to the photo-reductions of Cu(II) to Cu(I) and manganese oxides to Mn(II), respectively, while the uptake of Mo is a consequence of the reduction, mediated by organisms, of molybdate to Mo(V) or Mo(IV). Cadmium, on the other hand, appears to be bioaccumulated in the films. 相似文献
75.
Fumiaki Nakata Tadayuki Kodama Kazuhiro Shimasaku Mamoru Doi Hisanori Furusawa Masaru Hamabe Masahiko Kimura Yutaka Komiyama Satoshi Miyazaki Sadanori Okamura Masami Ouchi † Maki Sekiguchi Yoshihiro Ueda Masafumi Yagi Naoki Yasuda 《Monthly notices of the Royal Astronomical Society》2005,357(4):1357-1362
76.
Sato Minoru Oba Takashi Hosokawa Takao Yamaguchi Toshiyasu Nakano Toshiki Saito Tadao Muramoto Koji Kahara T akashi Funayama Katsura Kobayashi Akio Nakano Takahisa 《中国海洋大学学报(英文版)》2005,4(3):209-213
Brown alga ( Undaria pinnatifida) was treated with alginate lyase and hydrolyzed using 17 kinds of proteases and the inhibitory activity of the hydrolysates for the angiotensin-I-converting enzyme (ACE) was measured. Four hydrolysates with potent ACE-inhibitory activity were administered singly and orally to spontaneously hypertensive rats (SHRs). The systolic blood pressure of SHRs decreases significantly after single oral administration of the brown alga hydrolysates by pro- tease S ' Amano' (from Bacillus stearothermophilus) at the concentration of 10 (mg protein) (kg body weight)^ - 1. In the 17 weeks of feeding experiment, 7-week-old SHRs were fed standard diet supplemented with the brown alga hydrolysates for 10 weeks. In SHRs fed 1.0 and 0.1% brown alga hydrolysates, elevating of systolic bloodpressure was significantly suppressed for 7 weeks. To elucidate the active components, the brown alga hydrolysates were fractionated by 1-butanol extraction and HPLC on a reverse-phase column. Seven kinds of ACE-inhibitory peptides were isolated and identified by amino acid composition analysis, sequence analysis, and LC-MS with the results Val-Tyr, Ile-Tyr, Ala-Trp, Phe-Tyr, Val-Trp, Ile-Trp, and Leu-Trp. Each peptide was determined to have an antihypertensive effect after a single oral administration in SHRs. The brown alga hydrolysates were also confirmed to decrease the blood pressure in humans. 相似文献
77.
Minoru Oda 《Astrophysics and Space Science》1989,160(1-2):19-25
On the basis of my experience in the X-ray astronomy, and on some typical highlights of multi-wavelength observations, I emphasize the importance of collaboration between space astronomy and ground-based astronomy.Paper presented at the Symposium on the JNLT and Related Engineering Developments, Tokyo, November 29–December 2, 1988. 相似文献
78.
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