389 research outputs found
STUDIES ON THE FRUCTIFICATION OF "SHINANO WALNUT", A STRAIN OF JUGLANS REGIA L. 1. MORPHOLOGY AND ECOLOGY OF THE STAMINATE CATKIN AND THE POLLEN
ArticleJOURNAL OF THE FACULTY OF TEXTILE SCIENCE AND TECHNOLOGY, SHINSHU UNIVERSITY. SERIES. E, AGRICULTURE AND SERICULTURE 7: 1-20(1974)departmental bulletin pape
STUDIES ON THE FRUCTIFICATION OF "SHINANO WALNUT", A STRAIN OF JUGLANS REGIA L. II. MORPHOLOGY AND ECOLOGY OF THE PISTILLATE FLOWER AND THE CLUSTER
ArticleJOURNAL OF THE FACULTY OF TEXTILE SCIENCE AND TECHNOLOGY, SHINSHU UNIVERSITY. SERIES. E, AGRICULTURE AND SERICULTURE 8: 1-15(1975)departmental bulletin pape
Sakurajima-Satsuma (Sz-S) and Noike-Yumugi (N-Ym) tephras: new tephrochronological marker beds for the last deglaciation, southern Kyushu, Japan
Two prominent tephras, Sakurajima-Satsuma (Sz-S) erupted from Sakurajima volcano and Noike-Yumugi (N-Ym) erupted from Kuchierabujima Island, provide new key marker beds for dating and synchronizing palaeoenvironmental and archaeological records in the last deglaciation in southern Japan. These tephras were identified on the basis of glass major-element compositions in two distal areas, a marine core (IMAGES MD98-2195) in the northern part of the East China Sea and on the central part of Tanegashima Island, and related their stratigraphic positions to the marine oxygen isotope-based chronology. In MD98-2195, Sz-S, 0.8 cm in thickness at 9.12 m depth and N-Ym, 3 cm in thickness at 9.30 m depth, are both white, vitric, ash-grade tephras. On Tanegashima Island, Sz-S, 10 cm in thickness and N-Ym, 3 cm in thickness, are stratigraphically constrained by well-characterised marker tephras Kikai-Akahoya (7,300 cal BP) and Aira-Tn (29,000 cal BP). Sz-S is rhyolitic and homogeneous on the basis of glass major-element compositions assayed by electron microprobe. Pumiceous glass shards predominant in distal Sz-S tephra indicate that it derived from pumice fall units that correspond to pumiceous and phreatomagmatic fine ash units constituting proximal Sz-S tephra. N-Ym is rhyolitic and glass major-element analyses reveal compositional diversity between units, suggesting that the lower and middle tephra units dispersed to the east, whereas the upper unit was dispersed north to north-west from the vent.
Stratigraphically, Sz-S occurs at around the start of the late-glacial reversal (cooling) in oxygen isotope records of MD98-2195, corresponding to the end of GI-1 and the start of GS-1 in the ice-core events of NGRIP (GICC05), consistent with a terrestrial age of ˜12,800 cal BP. Based on the oxygen isotope stratigraphy, the tephra identified in the core as N-Ym at 9.30 m depth is close to the end of Greenland GI-1 and hence has an age of ˜13,000 cal BP, but on Kuchierabujima Island it has an age based on ¹⁴C assay of charcoal of c. 14,900 cal BP. Although this age discrepancy (14.9 vs 13.0 cal ka) needs resolution, the occurrence in core MD98-2195 of N-Ym shows that it is more widespread than hitherto demonstrated. The widespread distributions and key stratigraphic positions for the two marker tephras indicate that they are thus critical isochrons for precise correlation of palaeoenvironmental changes and prehistoric cultural events during the last deglaciation in southern Kyushu, and for relating such changes and events to the ice-core chronology via the marine oxygen isotope chronostratigraphy
Global Structure of Optically Thin, Magnetically Supported, Two-Temperature, Black Hole Accretion Disks
We present global solutions of optically thin, two-temperature black hole
accretion disks incorporating magnetic fields. We assume that the
{\pi}{\phi}-component of the Maxwell stress is proportional to the total
pressure, and prescribe the radial dependence of the magnetic flux advection
rate in order to complete the set of basic equations. We obtained magnetically
supported (low-{\beta}) disk solutions, whose luminosity exceeds the maximum
luminosity for an advection-dominated accretion flow (ADAF), L > 0.4 {\alpha}^2
L_Edd, where L_Edd is the Eddington luminosity. The accretion flow is composed
of the outer ADAF, a luminous hot accretion flow (LHAF) inside the transition
layer from the outer ADAF to the low-{\beta} disk, the low-{\beta} disk, and
the inner ADAF. The low-{\beta} disk region becomes wider as the mass-accretion
rate increases further. In the low-{\beta} disk, the magnetic heating balances
the radiative cooling, and the electron temperature decreases from ~ 10^9.5 K
to ~ 10^8 K as the luminosity increases. These results are consistent with the
anti-correlation between the energy cutoff in X-ray spectra (hence the electron
temperature) and the luminosity when L > 0.1 L_Edd, observed in the bright/hard
state during the bright hard-to-soft transitions of transient outbursts in
galactic black hole candidates.Comment: 27 pages, 15 figures, accepted for Publications of Astronomical
Society of Japa
Local density of states and superconducting gap in the iron chalcogenide superconductor FeSeTe observed by scanning tunneling spectroscopy
We report on the first investigation of the quasiparticle local density of
states and superconducting gap in the iron chalcogenide superconductor
FeSeTe ( K). The surface of
a cleaved crystal revealed an atomic square lattice, superimposed on the
inhomogeneous background, with a lattice constant of \AA without any
reconstruction. Tunneling spectra measured at 4.2 K exhibit the superconducting
gap, which completely disappears at 18 K, with a magnitude of meV,
corresponding to .In stark contrast
to the cuprate superconductors, the value of the observed superconducting gap
is relatively homogeneous, following a sharp distribution with a small standard
deviation of 0.23 meV. Conversely, the normal-state local density of states
observed above shows spatial variation over a wide energy
range of more than 1 eV, probably due to the excess iron present in the
crystal.Comment: 4 pages, 5 figure
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