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181.
J. Sato Y. Matsumoto K. Yoshimura S. Kubo J. Kotoku S. Masuda M. Sawa K. Suga M. Yoshimori T. Kosugi T. Watanabe 《Solar physics》2006,236(2):351-368
The flare catalogue of the Yohkoh mission is compiled and linked to this article as an electronic supplement. For showing flare characteristics over wide energy
range concisely, we provide the images of Hard X-ray Telescope (HXT) and the Soft X-ray Telescope (SXT), and the spectra of
Hard X-ray Spectrometer (HXS) and Gamma-Ray Spectrometer (GRS) with the Wide Band Spectrometer (WBS) time profiles. The energy
versus pulse height (PH) data channels in HXS and GRS are re-calibrated by using the data of the whole mission period. Secular
gain changes are recognized in HXS, and the characteristics of power-law flare spectra simultaneously observed by HXT and
HXS confirms the trend. The GRS gains are different for the flare observations during the previous maximum and for the current
maximum. The total of 33 γ -ray events are observed, and for 12 of them γ-ray flare spectra are obtained.
Electronic supplementary material to this article is available at and is accessible for authorized users. 相似文献
182.
T. Noguchi M. Kimura T. Hashimoto M. Konno T. Nakamura M. E. Zolensky A. Tsuchiyama T. Matsumoto J. Matsuno R. Okazaki M. Uesugi Y. Karouji T. Yada Y. Ishibashi K. Shirai M. Abe T. Okada 《Meteoritics & planetary science》2014,49(7):1305-1314
We observed cross sectional ultra‐thin sections near the surface of 12 particles recovered from the S‐type asteroid Itokawa by the Hayabusa spacecraft in 2010, using spherical aberration–corrected STEM and conventional TEM. Although their mineralogy is almost identical to the equilibrated LL chondrites and therefore basically anhydrous, micrometer‐to‐submicrometer‐sized sylvite was identified on the surface of Itokawa particle RA‐QD02‐0034. Separately, micrometer‐sized halite was also identified on the surface of Itokawa particle RA‐QD02‐0129. Detailed inspection of the sample processing procedures at the JAXA's Planetary Materials Sample Curation Facility and textural observation of the sylvite and halite indicate that they were clearly present on two Itokawa particles before they were removed from Clean Chamber #2 at JAXA. However, there is no direct evidence for their extraterrestrial origin at present. If the sylvite and halite are extraterrestrial, their presence suggests that they may be more abundant on the surface of S‐type asteroids than previously thought. 相似文献
183.
Eri Hirakawa Akiko Murakami-Kitase Takamoto Okudaira Jun Inoue Hideo Yamazaki Shusaku Yoshikawa 《Environmental Earth Sciences》2011,64(3):833-840
Spheroidal carbonaceous particles (SCPs) are produced by the high-temperature combustion of fossil fuels and emitted in to
the atmosphere. The distribution and concentration of SCPs in sediments have been used as a proxy for the distribution of
pollutants emitted to the atmosphere. However, the effect on the distribution of SCPs due to industrial activity at nearby
industrial cities is yet to be quantified. To clarify the origin of SCPs of ~20 μm in size that are preserved in sediments,
we evaluated the abundance, surface morphology, and chemical composition of SCPs in sediment core samples recovered from industrial
cities in Japan (Tokyo, Osaka, and Nagasaki) and China (Beijing), with the cities being located at least ~500 km away from
each other. Vertical profiles of SCP concentration in sediment cores from the Japanese cities and Beijing are different, reflecting
the contrasting industrial histories of the two countries. The SCPs from different cities show contrasting morphological and
chemical characteristics, suggesting that ~20 μm SCPs in sediments from the industrial cities could represent the local combustion
history in detail, as the influx of local SCPs is dominant at such sites. 相似文献
184.
Strain localization developing inside soft rock specimens is examined through experimental observation and numerical simulation. In the experimental study, soft rock specimens are sheared at different strain rates under plane strain conditions and deformation and strain localization characteristics are analysed. Transition of localization mode from highly localized mode for higher strain rate to distributed and diffused mode of strain localization for lower strain rates was observed. In the numerical study, simulations of plane strain compression tests are carried out at different strain rates by using an overstressed‐type elasto‐viscoplastic model in finite element computations. The role of strain rates on setting gradients of strain fields across shear band is clarified. The probable mechanism for transition of localization mode is discussed. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
185.
186.
Y. Ueda K. Yamaoka J.E. Grove M. McCollough P. Durouchoux J. Rodriguez F. Mirabel J. Swank M. Feroci P. Casella A.J. Castro-Tirado C. Sánchez-Fernández S. Chaty H. Castaneda K. Kohno V. Dhawan S.A. Trushkin K. Ebisawa T. Kotani H. Inoue 《Astrophysics and Space Science》2001,276(1):25-28
We report results from multiwavelength observations of the microquasarGRS 1915+105 performed during the 2000 April campaign. This is one ofthe biggest campaigns ever made for this source covering the broadband from radio to γ-rays. Multiwavelength light curves compiledfrom all the data reduced up to date and broad band spectra obtainedwith ASCA and RXTE are presented. 相似文献
187.
Kohki Yoshida Toru Nakajima Yuki Matsumoto Ai Osaki Lalit Kumar Rai Jarrett W. Cruz Harutaka Sakai 《Island Arc》2021,30(1):e12408
Bengal Fan Miocene sediments were collected during International Ocean Discovery Program Expedition 354 and investigated using petrographic and detrital garnet chemistry analyses. The Miocene Siwalik Group, which is composed of sediments deposited in the Himalayan foreland basin, was also analyzed for comparison with the Bengal Fan data for the provenance change during the Miocene. Our petrographic analyses revealed that the Miocene sediments of the Bengal Fan and Siwalik Group consist predominantly of Higher Himalayan Crystalline (HHC)-derived detritus such as chloritoid, staurolite, sillimanite, and/or kyanite, which appear among the accessory minerals. The chemistry of the detrital garnet varies across the stratigraphy; most of the garnet is rich in almandine and poor in spessartine and pyrope. However, pyrope-rich garnet, which is considered to originate from the HHC core (granulite facies), was found in the lower to upper Miocene deposits. The deposition of HHC-derived detrital garnet began before the Middle Miocene (15 Ma) and before the Late Miocene (10–9 Ma) in the Siwalik Group. The Bengal Fan data, by contrast, indicated that pyrope-rich garnet appeared in the Early Miocene (17.3 Ma) and Late Miocene (8.5–6.5 Ma). We conclude that the Bengal Fan sediments record the erosion of the HHC zone since the Early Miocene that appears in the Siwalik sediments. Furthermore, we found that the HHC-derived inputs decreased from the late Middle Miocene (12 Ma) to the early Middle Miocene (10 Ma) in both the Nepal Himalaya foreland basin and the Bengal Fan. The disappearance of the HHC-derived detritus is probably the result of dilution by Lesser Himalayan detritus, which suggests that the Lesser Himalayan zone, which is composed of metamorphosed and unmetamorphosed sedimentary rocks, was uplifted. 相似文献
188.
189.
Masahiko Honda David Phillips Jeff W. Harris Takuya Matsumoto 《Earth and Planetary Science Letters》2011,301(1-2):43-51
We have undertaken helium, neon and argon step-heating, isotopic analyses of eleven polycrystalline diamonds of known peridotite/eclogite paragenesis from the Jwaneng kimberlite pipe, Botswana. In contrast to the findings of crustal noble gases in framesites from the same kimberlite pipe (Honda et al., 2004. Unusual noble gas compositions in polycrystalline diamonds: preliminary results from the Jwaneng kimberlite, Botswana. Chem. Geol. 203, 347–358.), the Jwaneng polycrystalline diamonds appear to contain similar noble gas isotopic compositions (particularly Ne) to those representing a mantle source for MORBs. This implies that the Jwaneng polycrystalline diamonds may have formed in recent times, possibly close to the time of kimberlite emplacement at ~ 235 Ma. In contrast, Jwaneng framesites could be as old as gem diamonds (mineral inclusion ages of ~ 2.9 Ga). Furthermore, the data indicate that the sub-continental mantle lithosphere in the region has heterogeneous Ne isotopic compositions, or that these compositions changed over time from crustal Ne (as observed in the framesites) to MORB-like (as observed in the polycrystalline diamonds). 相似文献
190.
Hyung-Jin Kim Kumiko Takata Katsunori Tanaka Ryoji Yamashima Jun Matsumoto Kazuyuki Saito Toshihiko Takemura Tetsuzo Yasunari 《Asia-Pacific Journal of Atmospheric Sciences》2014,50(4):423-435
A series of 60-year numerical experiments starting from 1851 was conducted using a global climate model coupled with an aerosol-cloud-radiation model to investigate the response of the Asian summer monsoon to variations in the secondary organic aerosol (SOA) flux induced by two different estimations of biogenic volatile organic compound (BVOC) emissions. One estimation was obtained from a pre-existing archive and the other was generated by a next-generation model (the Model of Emissions of Gases and Aerosols from Nature, MEGAN). The use of MEGAN resulted in an overall increase of the SOA production through a higher rate of gasto-particle conversion of BVOCs. Consequently, the atmospheric loading of organic carbon (OC) increased due to the contribution of SOA to OC aerosol. The increase of atmospheric OC aerosols was prominent in particular in the Indian subcontinent and Indochina Peninsula (IP) during the pre- and early-monsoon periods because the terrestrial biosphere is the major source of BVOC emissions and the atmospheric aerosol concentration diminishes rapidly with the arrival of monsoon rainfall. As the number of atmospheric OC particles increased, the number concentrations of cloud droplets increased, but their size decreased. These changes represent a combination of aerosol-cloud interactions that were favorable to rainfall suppression. However, the modeled precipitation was slightly enhanced in May over the oceans that surround the Indian subcontinent and IP. Further analysis revealed that a compensating updraft in the surrounding oceans was induced by the thermally-driven downdraft in the IP, which was a result of surface cooling associated with direct OC aerosol radiative forcing, and was able to surpass the aerosolcloud interactions. The co-existence of oceanic ascending motion with the maximum convective available potential energy was also found to be crucial for rainfall formation. Although the model produced statistically significant rainfall changes with locally organized patterns, the suggested pathways should be considered guardedly because in the simulation results, 1) the BVOC-induced aerosol direct effect was marginal; 2) cloud-aerosol interactions were modeldependent; and 3) Asian summer monsoons were biased to a nonnegligible extent. 相似文献