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111.
The wave height distribution with Edgeworth’s form of a cumulative expansion of probability density function (PDF) of surface elevation are investigated. The results show that a non-Gaussian model of wave height distribution reasonably agrees with experimental data. It is discussed that the fourth order moment (kurtosis) of water surface elevation corresponds to the first order nonlinear correction of wave heights and is related with wave grouping. 相似文献
112.
利用流水饲养法研究了不同浓度的三丁基氧化锡 (0 .5 μg/ L和 1.0 μg/ L TBTO)对太平洋牡蛎卵巢中卵母细胞直径、RNA/ DNA比、蛋白质和卵黄蛋白含量的影响。卵母细胞径的增长在0 .5 μg/ L实验组受到阻碍 ,并随着 TBTO浓度的增大而更加明显。TBTO暴露组的 RNA/ DNA比在精巢中无明显变化 ,但在卵巢中显著低于对照组。 TBTO暴露组的卵巢中蛋白质和卵黄蛋白含量显示了与 RNA/ DNA比相同的变化趋势 ,表明 TBTO的积累阻碍卵黄蛋白的合成。TBTO暴露4 2 d采集的牡蛎样品中出现 3个雌雄同体 ,暗示 TBTO可能引起牡蛎发生性转变进而产生雌雄同体 相似文献
113.
Toshio Kataoka Eiji Yunoki Mitsuo Shimizu Tadashige Mori Osamu Tsukamoto Satoshi Takahashi Hironori Fudeyasu Yukitaka Ohashi Ken Sahashi Toshihiko Maitani Koh'ichi Miyashita Toru Iwata Takayuki Sasaki Yoko Fujikawa Akira Kudo Roger H. Shaw 《Boundary-Layer Meteorology》2003,107(1):219-249
Atmospheric activity concentrations of 212Pb and short-lived 222Rndaughters, together with meteorological elements, have been observed continuously atthree sites at Kamisaibara Village in Japan. In addition, atmospheric activity concentrationof 222Rn, equilibrium-equivalent concentration of 222Rn and conditionsof the lower atmosphere were observed for three intensive observation periods at Akawase,one of the three sites in Kamisaibara Village. The equilibrium-equivalent concentration of222Rn is almost the same as the atmospheric activity concentration of short-lived222Rn daughters.The activity concentrations of 212Pb and the short-lived 222Rn daughtersand their ratio were low in the daytime owing to convective mixing, and high at nightowing to the surface-based inversion during periods of no precipitation. Their variationshave several patterns corresponding to the scale of the drainage wind or weak mixing.Mechanical mixing due to strong winds through both day and night during the first andsecond observation periods made the atmospheric activity concentrations of 212Pb and the short-lived 222Rn daughters continuously low. However, their ratios werecontinuously high during the first period yet continuously low during the second period.This difference can be explained by the effect ofextraction of 220Rn and 222Rndue to strong winds and snow cover. There were also cases in which the ratio of theatmospheric activity concentration of 212Pb to that of the short-lived 222Rndaughters at night was equal to or less than the ratio in the daytime. Thisinverse trend, asin the periods of no precipitation mentioned above, is considered to be due to near-neutralconditions on these nights.We find a difference in the ratio of the equilibrium-equivalent concentration of222Rn (the activity concentration of short-lived 222Rn daughters) tothe activity concentration of 222Rn during the first observation period and thatduring the second. The difference can be explained by snow cover on the ground. Wealso find differences among the ratios of the activity concentration of the short-lived222Rn daughters to that of 222Rn during the three observation periods.These differences can be explained by the submergence of paddy fields. 相似文献
114.
Takeshi Mori 《Contributions to Mineralogy and Petrology》1977,59(3):261-279
Three methods of geothermometry, currently used for spinel lherzolites, are refined based on new experiments on subsolidus phase equilibria of olivine, pyroxenes and spinel in CaO-MgO-Al2O3-SiO2 and natural rock systems at 16 kb and 1200 °C. Although quasi-thermodynamic modelling is employed, the methods are essentially based on the pyroxene solvus, alumina contents in clinopyroxene and orthopyroxene. Increasing alumina contents in pyroxenes reduce enstatite and diopside components in clinopyroxene and orthopyroxene, respectively. Thus, neglect of alumina in pyroxenes causes underestimates of temperatures by the solvus method.The three geothermometers were tested by applying them to homogeneous spinel lherzolites which were especially selected for this purpose. Coincidence of the three temperatures thus estimated gives confidence in the effectiveness of the geothermometers.They were also applied to spinel lherzolite nodules in basalts and intrusive lherzolites described in the literature. It was found that equilibration temperature of the nodules varies from 1000 °C to 1300 °C, i.e., temperatures somewhat higher than have been generally thought. In contrast to the nodules, the intrusive spinel lherzolites show extensive disequilibrium, which is probably due to retrogressive metamorphism suffered by the intrusives. 相似文献
115.
116.
Two modes of climatic control in the Holocene stalagmite record from the Japan Sea side of the Japanese islands 下载免费PDF全文
Tomomi Sone Akihiro Kano Kenji Kashiwagi Taiki Mori Tomoyo Okumura Chuan‐Chou Shen Masako Hori 《Island Arc》2015,24(3):342-358
The Holocene stalagmite FG01 collected at the Fukugaguchi Cave in Itoigawa, central Japan provides a unique high‐resolution record of the East Asian winter monsoon. Because of the climate conditions on the Japan Sea side of the Japanese islands, the volume of precipitation during the winter is strongly reflected in the stalagmite δ18O signal. Examination of the carbon isotopes and the Mg/Ca ratio of FG01 provided additional information on the Holocene climate in Itoigawa, which is characterized by two different modes separated at 6.4 ka. Dripwater composition and the correlation between the δ13C and Mg/Ca data of FG01 indicate the importance of prior calcite precipitation (PCP), a process that selectively eliminated 12C and calcium ions from infiltrating water from CO2 degassing and calcite precipitation. In an earlier period (10.0–6.4 ka), an increase in soil pCO2 associated with warming and wetting climate trends was a critical factor that enhanced PCP, and resulted in an increasing trend in the Mg/Ca and δ13C data and a negative correlation between the δ13C and δ18O profiles. A distinct peak in the δ13C age profile at 6.8 ka could be a response to an increase of approximately 10% in C4 plants in the recharge area. At 6.4 ka, the climate mode changed to another, and correlation between δ18O and δ13C became positive. In addition, a millennial‐scale variation in δ18O and pulsed changes in δ13C and Mg/Ca became distinct. Assuming that δ18O and PCP were controlled by moisture in the later period, the volume of precipitation was high during 6.0–5.2, 4.4–4.0, and 3.0–2.0 ka. In contrast, the driest interval in Itoigawa was during 0.2–0.4 ka, and broadly corresponds to the Little Ice Age. 相似文献
117.
Evidence for abrupt coastal uplifts has been found in emerged sessile assemblages in a sea cave at the southern end of the Izu Peninsula, central Japan. We identified five sessile assemblage zones: Zones I to V, in ascending order. The uppermost zone (Zone I), located at an elevation of 2.7–3.5 m above the present‐day mean sea level (amsl), is a hard massive shellcrust consisting mainly of the barnacles Chthamalus challenger and the tube worm Pomatoleios kraussii. Zone II, at 2.35–2.7 m amsl, is dominated by well‐preserved individuals of C. challenger. Zone III, at 2.0–2.35 m amsl, is strongly eroded and consists mainly of C. challenger and P. kraussii. Zone IV, at 1.6–2.0 m amsl, is characterized by the co‐occurrence of very fresh shells of C. challenger and P. kraussii. Zone V (the lowest zone), at 1.0–1.60 m amsl, is characterized by the co‐occurrence of very fresh shells of Saccostrea kegaki and P. kraussii, and by the absence of C. challenger. Radiocarbon dating by accelerator mass spectrometry (AMS) and the presence of modern taxa in the sessile assemblages suggest that three episodes of coastal uplift have occurred in the area, during AD 570–820, AD 1000–1270, and AD 1430–1660, with magnitudes of 0.9–2.0 m, 0.3–0.8 m, and 1.9–2.2 m, respectively. 相似文献
118.
119.
Pedro A. Hernández Nemesio M. Pérez Thráinn Fridriksson Jolie Egbert Evgenia Ilyinskaya Andri Thárhallsson Gretar ívarsson Gestur Gíslason Ingvi Gunnarsson Birgir Jónsson Eleazar Padrón Gladys Melián Toshiya Mori Kenji Notsu 《Bulletin of Volcanology》2012,74(10):2435-2448
We report the first detailed study of spatial variations on the diffuse emission of carbon dioxide (CO2) and hydrogen sulfide (H2S) from Hengill volcanic system, Iceland. Soil CO2 and H2S efflux measurements were performed at 752 sampling sites and ranged from nondetectable to 17,666 and 722?g?m?2?day?1, respectively. The soil temperature was measured at each sampling site and used to evaluate the heat flow. The chemical composition of soil gases sampled at selected sampling sites during this study shows they result from a mixing process between deep volcanic/hydrothermal component and air. Most of the diffuse CO2 degassing is observed close to areas where active thermal manifestations occur, northeast flank of the Hengill central volcano close to the Nesjavellir power plant, suggesting a diffuse degassing structure with a SSW?CNNE trend, overlapping main fissure zone and indicating a structural control of the degassing process. On the other hand, H2S efflux values are in general very low or negligible along the study area, except those observed at the northeast flank of the Hengill central volcano, where anomalously high CO2 efflux and soil temperatures were also measured. The total diffuse CO2 emission estimated for this volcanic system was about 1,526?±?160?t?day?1 of which 453?t?day?1 (29.7?%) are of volcanic/hydrothermal origin. To calculate the steam discharge associated with the volcanic/hydrothermal CO2 output, we used the average H2O/CO2 mass ratio from 12 fumarole samples equal to 88.6 (range, 9.4?C240.2) as a representative value of the H2O/CO2 mass ratios for Hengill fumarole steam. The resulting estimate of the steam flow associated with the gas flux is equal to 40,154?t?day?1. The condensation of this steam results in thermal energy release for Helgill volcanic system of 1.07?×?1014?J?day?1 or to a total heat flow of 1,237?MWt. 相似文献
120.
The Sanbagawa Belt generally shows higher metamorphic grade at higher structural levels. This inversion can be interpreted as reflecting an original inverted thermal structure typical of subduction zone environments. However, repetitions in the distribution of the metamorphic zones seen in central Shikoku, Japan, clearly show the original thermal structure has been affected by deformation after the peak of metamorphism. This repetition has been attributed to both the action of tectonic discontinuities and regional folding. It is important to distinguish between these two interpretations to determine the extent to which the original subduction zone sequence is preserved. Analyses of lithological and structural data reveal the presence of a large‐scale post‐metamorphic fold in the central part of the highest grade region. This folding has an axis that coincides with the thermal axis implied by the distribution of the metamorphic zonation, suggesting the repetition of metamorphic zones in this area can be accounted for by folding without the need for major discontinuities. 相似文献