Contents of strontinm-90 and ruthenium-106 in beach and shallow water deposits of noto peninsula

⁹⁰Sr,¹⁰⁶Ru, natural strontium and major elements were studied in 12 samples of beach deposits from Togi, Fukuura and Shiga, and in 26 samples of shallow water sediments from sea off Fukuura, Noto Peninsula, Ishikawa Pref., Japan.The average contents of natural strontium and⁹⁰Sr in the beach deposits were 488 ppm ranging from 247 to 1,550 ppm and 45±9 pCi kg^–1-dry mud ranging from 18 to 72 pCi kg^–1-dry mud, respectively. While the average contents of natural strontium,⁹⁰Sr and¹⁰⁶Ru in the sediments were 234 ppm ranging from 136 to 415 ppm, 22±6 pCi kg^–1-dry sand ranging from 7 to 48 pCi kg^–1-dry sand and 0.6 ±0.2 nCi kg^–1-dry ranging from 0.3 to 1.2 nCi kg^–1-dry, respectively.The average contents of each natural strontium and⁹⁰Sr in the beach deposits were about two times higher than those in the shallow water sediments. But no obvious relation of natural strontium to⁹⁰Sr was found in all the samples. The enrichment of⁹⁰Sr and¹⁰⁸Ru in the beach deposits or tthe sediments were as high as 150320 and of 2,0003,000 compared with average contents of⁹⁰Sr and¹⁰⁶Ru in a liter of surface water from the Japan Sea. It is to be noticed that the average¹⁰⁶Ru to⁹⁰Sr ratio of 27 for the shallow water sediments is much higher than the average of 1.0 for surface sea water of the Japan Sea.As to major elements of the samples, the beach deposits are rich in silicon (Av. 70.89 ±0.92% SiO₂), but poor in iron (Av. 2.99±0.32% Fe₂O₃). Whereas the shallow water sediments are poor in silicon (Av. 52.96±10.33% SiO₂) and rich in iron (Av. 5.50±1.90% Fe₂O₃), calcium (Av. 9.64±9.22% CaO) and magnesium (Av. 2.83±1.58% MgO).     

浙江东阳晚白垩世早期翼龙足迹

根据中国浙江东阳上白垩统金华组发现的4个翼龙足迹,建立翼龙一新的遗迹种：东阳翼龙足迹。它具有以下特征：手迹的第Ⅱ和第Ⅲ指夹角为29°,第Ⅰ指和第Ⅱ指的夹角为52°;足迹的长与宽的比率为0.17,除了翼龙足迹外,在同一层位中还发现有蜥脚类、鸟脚类、兽脚类、帯蹼和不具蹼的鸟类足迹。这些足迹化石的发现,为研究该地区的古生态环境及以后动物的骨骼化石,尤其是翼龙骨骼化石提供了重要依据。     

A derivation of the scaling law, the power law and the scaling relation for fetch-limited wind waves using the renormalization group theory

A state of wind waves at a fetch is assumed to be transformed into another state of wind waves at a different fetch by the renormalization group transformation. The scaling laws for the covariance of water surface displacement and for the one-dimensional and two-dimensional spectrum and the power law for the growth relation are derived from the fact that the renormalization group transformation constitutes a semigroup. The scaling relation or the relation among the exponents of the power law is also derived, using the two assumptions that the renormalization group transformation is applicable to fetch-limited wind waves and that the saturated range exists, which implies that the directional distribution function of energy in the wave number region much larger than the peak wave number does not depend on wave number.     

Chandra observations of the luminous infrared galaxy NGC 3256

We present a detailed analysis of high-resolution Chandra observations of the merger system NGC 3256, the most infrared-luminous galaxy in the nearby universe. The X-ray data show that several discrete sources embedded in complex diffuse emission contribute ≳20 per cent of the total emission     in the  0.5–10 keV  energy range). The compact sources are hard and extremely bright and their emission is probably dominated by accretion-driven processes. Both galaxy nuclei are detected with  L_X∼3–10×10⁴⁰ erg s⁻¹  . No evidence is found for the presence of an active nucleus in the southern nucleus, contrary to previous speculation. Once the discrete sources are removed, the diffuse component has a soft spectrum that can be modelled by the superposition of three thermal plasma components with temperatures   kT =0.6  , 0.9 and 3.9 keV. Alternatively, the latter component can be described as a power law with index  Γ∼3  . Some evidence is found for a radial gradient of the amount of absorption and temperature of the diffuse component. We compare the X-ray emission with optical, H α and NICMOS images of NGC 3256 and find a good correlation between the inferred optical/near-infrared and X-ray extinctions. Although inverse Compton scattering could be important in explaining the hard X-rays seen in the compact sources associated with the nuclei, the observed diffuse emission is probably of thermal origin. The observed X-ray characteristics support a scenario in which the powerful X-ray emission is driven solely by the current episode of star formation.     

青藏高原那曲地区冰雹天气系统中的大气电场

利用1998年4～9月间进行的GAME-TIBET青藏高原云和降水的多普勒雷达及大气平均电场加强期观测实验资料, 对青藏高原那曲地区的冰雹天气系统中的大气电场作了定量观测和研究.结果表明: 在降雹过程中大气电场强度基本上均为负值, 其峰值也均强于-22 kVm-1; 在降雹过程中随着降雹时间的临近, 大气电场强度不断增强, 但降雹开始时大气电场强度并未达到其峰值, 峰值出现的时刻比开始降雹的时刻略有滞后; 在各降雹日中, 较强的大气电场强度基本上对应着各冰雹谱分布段较多的冰雹数目, 而这种较好的相关在各谱分布段上都表现出来; 随着降雹时间的临近, 每5 min闪电频数不断增强.在开始降雹时每5 min闪电频数平均达到43, 峰值的出现时刻略滞后于开始降雹的时刻, 这一滞后时间一般平均在3 min左右; 在降雹过程中, 单位面积中的冰雹数目与对应时段内总闪电数有着较好的对数关系, 相关系数R为0.954 0.在降雹过程的时间序列上, 冰雹云成熟期过后, 总闪电次数与冰雹降雹率成反相关.