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Abstract: Synchrotron X-ray fluorescence analyses on individual hypersaline fluid inclusions were tested to using synchrotron source at Tsukuba (KEK), Japan. The XRF instrumentation at KEK meets the purpose of fluid inclusion analysis, nondestructive, multi–element, ppm detection limits, with micro spatial resolution. In practice, however, the quantitative chemical analysis of fluid inclusion requires further considerable data accumulation. Semi-quantitative distribution of elements (mass number > 25) in single fluid inclusion was obtained. 相似文献
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Takanori Shimizu Koji Tamai Ikuhiro Hosoda Shoji Noguchi Yuji Kominami Toshio Abe Kenzo Kitamura Ushio Kurokawa Delphis F. Levia Tayoko Kubota Naoki Kabeya Shin'ichi Iida Tatsuhiko Nobuhiro Shinji Sawano Sho Iwagami Akira Shimizu Yoshio Tsuboyama 《水文研究》2021,35(10):e14376
This data note introduces a database of long-term daily total precipitation and stream discharge data for seven forested watersheds in Japan that have been continuously monitored by the Forestry and Forest Products Research Institute. Three of the watersheds started data collection in the 1930s. Forest cover across the sites ranges from cool to warm temperate regions with the latitude spanning from 31 to 44° N and annual precipitation ranging from 1200 to 3000 mm yr−1. The effects of vegetation change via clearcutting, thinning and forest fire (among other stressors) on stream discharge can be analysed from the long-term observation sites. Moreover, this multi-site dataset allows for inter- and intra-site comparisons of annual water loss (difference of annual precipitation and stream discharge). These long-term datasets can provide comprehensive insights into the effects of climate change and other stressors on forested ecosystems, not only in Japan but across a spectrum of forest types, if combined with other long-term records from other forested watersheds across the world. 相似文献
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Morita T Ohtsuka Y Fujimoto K Minamisako Y Iida R Nakamura M Kayama T 《Marine pollution bulletin》2010,60(12):2311-2322
The anthropogenic radionuclides, 137Cs, 90Sr, 108mAg, 239+240Pu, were measured in two Chionoecetes species, red queen crab (Chionoecetes japonicus) and snow crab (Chionoecetes opilio) collected around Japan during 1996–2007. There was no increase in the concentrations of these radionuclides and no large variation of the atom ratio of 240Pu/239Pu during this research period. These results indicated that the source of the radionuclides was not the radioactive wastes dumped by the former USSR and Russia and originated from past nuclear weapon tests. The higher atom ratio in the crab species than that from global fallout would be contributed by the Pacific Proving Grounds close-in fallout. The variability of the concentration of radionuclides in the crab species would result from the variability of the composition and quantity in the diet. However, the decrease in the concentration of radionuclides with sampling depth would depend on the concentration in the seawater and diet. 相似文献
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One-armedglobal oscillations in a non-selfgravitating polytropic disk rotating around a star are investigated. The unperturbed disk is axisymmetric, geometrically thin, and extends infinitely in the radial direction keeping its thickness constant. Perturbations considered are inviscid and adiabatic. It is found that there are one-armed retrograde wave modes which are trapped in an inner region of the disk. The eignefrequency of the lowest order mode is given by K(r
s)(z
0/r
s)2, wherer
s is the radius of the central star,z
0 is the half-thickness of the disk, and K(r
s) is the Keplerian angular frequency at the surface of the star.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
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To better understand the variation of water quality in the Mekong River, sampling and measurement were scheduled twice a week for about 3 years at Vientiane, followed by basic statistical analysis of the observed data. The frequent measurement revealed detailed characteristics of the water quality variation, which had not been detected by monthly observation in the previous studies. The variation in total ionic content was considered to be governed by dilution of the amount of water. Increases in turbidity could be attributed to physical effects including surface soil erosion and bed material resuspension at the time of discharge increase. Nitrogen concentrations were stably low during the low flow period and abruptly increased in May. After the annual maximum in late May, the nitrate concentration steadily decreased regardless of the remarkable rise in the discharge from mid‐July, whereas the ammonium concentration remained at a similar level until October. It was considered that the first small discernable runoff after the long dry season flushed the accumulated nitrogen in the surface soil and mobilized the nitrogen in the riverbed. The variation in phosphorus concentrations was different from that in nitrogen concentrations. During the high flow period, continual dilutions at discharge peaks and occasional large additions of phosphorus by surface runoff were suggested. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Marvin Lüpke Michael Leuchner Delphis Levia Kazuki Nanko Shin'ichi Iida Annette Menzel 《水文研究》2019,33(26):3391-3406
Forest canopies present irregular surfaces that alter both the quantity and spatiotemporal variability of precipitation inputs. The drop size distribution (DSD) of rainfall varies with rainfall event characteristics and is altered substantially by the forest stand properties. Yet, the influence of two major European tree species, European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) H. Karst), on throughfall DSD is largely unknown. In order to assess the impact of these two species with differing canopy structures on throughfall DSD, two optical disdrometers, one above and one below the canopy of each European beech and Norway spruce, measured DSD of both incident rainfall and throughfall over 2 months at a 10‐s resolution. Fractions of different throughfall categories were analysed for single‐precipitation events of different intensities. While penetrating the canopies, clear shifts in drop size and temporal distributions of incoming rainfall were observed. Beech and spruce, however, had different DSD, behaved differently in their effect on diameter volume percentiles as well as width of drop spectrum. The maximum drop sizes under beech were higher than under spruce. The mean ± standard deviation of the median volume drops size (D50) over all rain events was 2.7 ± 0.28 mm for beech and 0.80 ± 0.04 mm for spruce, respectively. In general, there was a high‐DSD variability within events indicating varying amounts of the different throughfall fractions. These findings help to better understand the effects of different tree species on rainfall partitioning processes and small‐scale variations in subcanopy rainfall inputs, thereby demonstrating the need for further research in high‐resolution spatial and temporal properties of rainfall and throughfall. 相似文献
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Agusa T Yasugi SY Iida A Ikemoto T Anan Y Kuiken T Osterhaus AD Tanabe S Iwata H 《Marine pollution bulletin》2011,62(5):963-975
Body distribution and growth- and nutritional status-dependent accumulation of 21 trace elements were investigated in harbor seals (Phoca vitulina) stranded in the North Sea coast in 2002. Higher concentrations and burdens of Mn, Se, Mo, Ag, Sn, Hg, and Bi in the liver, Cd in the kidney, As in the blubber, and Co, Sr, and Ba in the bone were observed. Significant positive correlations of hepatic Se, Mo, Ag, Cd, Sn, Hg, Tl, and Bi with standard body length were found, while significant negative relationships were detected for Mn, As, Rb, Sr, and Sb in the liver. Concentrations of Co, Se, Sr, Sn, Hg, and Bi in the liver, V, Sr, Ag, Sn, and Hg in the kidney, V, Mn, Co, Rb, Sr, Sn, Ba, and Pb in the blubber increased with decreasing blubber thickness of harbor seals, indicating enrichment of these elements in the target tissue by emaciation. 相似文献
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Formation of a Flare-Productive Active Region: Observation and Numerical Simulation of NOAA AR 11158
We present a comparison of the Solar Dynamics Observatory (SDO) analysis of NOAA Active Region (AR) 11158 and numerical simulations of flux-tube emergence, aiming to investigate the formation process of this flare-productive AR. First, we use SDO/Helioseismic and Magnetic Imager (HMI) magnetograms to investigate the photospheric evolution and Atmospheric Imaging Assembly (AIA) data to analyze the relevant coronal structures. Key features of this quadrupolar region are a long sheared polarity inversion line (PIL) in the central δ-sunspots and a coronal arcade above the PIL. We find that these features are responsible for the production of intense flares, including an X2.2-class event. Based on the observations, we then propose two possible models for the creation of AR 11158 and conduct flux-emergence simulations of the two cases to reproduce this AR. Case 1 is the emergence of a single flux tube, which is split into two in the convection zone and emerges at two locations, while Case 2 is the emergence of two isolated but neighboring tubes. We find that, in Case 1, a sheared PIL and a coronal arcade are created in the middle of the region, which agrees with the AR 11158 observation. However, Case 2 never builds a clear PIL, which deviates from the observation. Therefore, we conclude that the flare-productive AR 11158 is, between the two cases, more likely to be created from a single split emerging flux than from two independent flux bundles. 相似文献