EFFECT OF SULPHATE-REDUCING BACTERIA ON ELECTRO-CHEMICAL CORROSION BEHAVIOR OF 16Mn STEEL IN SEA MUD

ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｗａｓｇｅｎｅｒａｌｌｙｃｏｎｓｉｄｅｒｅｄｐｒｅｖｉｏｕｓｌｙｔｈａｔｔｈｅｃｏｒｒｏｓｉｏｎｏｆｓｔｅｅｌｉｎｓｅａｍｕｄｗａｓｎｏｔｓｅｒｉｏｕｓ.Ｈｏｗｅｖｅｒ,ｉｔｗａｓｌａｔｅｒｆｏｕｎｄｔｈａｔｔｈｅｃｏｒｒｏｓｉｏｎｒａｔｅｏｆｓｔｅｅｌｉｎｓｏｍｅｓｅａｍｕｄｗａｓｈｉｇｈｅｒｔｈａｎｔｈａｔｉｎｓｅａｗａｔｅｒ(Ｋｉｎｇ,1980;Ｓｅｈｍｉｄｅ,1982;Ｇｕｏｅｔａｌ.,1997;Ｈｏｕ,1998).Ｔｈｅｒｅａｒｅｓｏｍｅｒｅｐｏｒｔｓｔｈａｔｔｈｅｃｏｒｒｏｓｉｏｎｒ…     

Petroleum Hydrocarbon Distribution Features in Water and Sediment off Fujian Shore

This study on the distribution features of petroleum hydrocarbon in water and sedi-ment off the Fujian shore using data obtained from the baseline research on oceanic contamination in Fujian showed that:during the research preiod,petroleum hydrocarbon concentrations in water varied from 5.77μg/L to 37.28μg/L,averaged 14.48 μg/L;was lower in the wet seasson than in the dry season;and was highest in the Minjiang Estuary and Jiulong Estuary in both seasons ,The petorleum hydrocarbon concentrations in shore sediment varied from 14.48 mg/kg to 784.36 mg/kg,averaged 133.3 mg/kg ,and was closely related to sediment types (granularity).     

βCephei变星的脉动不稳定带的研究(英文)

在本文中我们对两种不同的 βCephei变星的理论脉动不稳定带作了比较。它们具有明显的不同之处。为了确定这种变星的脉动不稳定带的轮廓 ,我们根据 4 9颗 βCephei变星的观测资料作了统计研究。在从样本星的色指数 (B -V) ,(U -B)和视差得到它们的有效温度和光度之后 ,我们发现在赫罗图上它们大多数是位于主序带内的。而且这些样本星的质量都位于 7M⊙ 到 30M⊙ 之间。和理论模型的比较表明我们提出的具有光度上边界和红蓝边界的 βCephei变星的理论脉动不稳定带跟观测吻合得更好     

介质横向不均匀对震后地表位移场的影响

利用三维有限元模拟两层地球模型(包括弹性层和粘弹性层)介质的横向不均匀和断层错动的复杂性对震后地表位移场的影响，其数值结果包括弹性解和粘弹性解。结果表明，震后位移场的分布特征不仅与粘弹性层的流变特性有关，还与弹性层介质的剪切模量以及断层的同震错动有关。     

Deep Processes of Basin Evolution:A Case Study of the Southern Songliao Basin and Adjacent Area,NE China in Mesozoic-Cenozoic

1IntroductionOne of the key factors related to basin geody-namics is deep process controlling formation and evolution of sedimentary basin. Depth and tempera-ture of asthenosphere,existence of mantle plume,occurrence of mantle melting,and amounts of melts under depressurization during thinning of lithosphere are controlling factors influenced formation and characteristics of extensional basin directly (Li,1994). Rifting is probably governed by frictional forces exerted on the base of litho…     

On the influence of magnetic fields on level populations

The influence of magnetic fields on the energy level populations of atoms is firstly studied by analysing the Stokes profiles of Fe  i 6302.5 forming in the solar magnetized atmosphere, with the aid of a departure factor defined to evaluate the deviation from the normal Boltzmann distribution without a magnetic field. This factor is directly related to the ratio of line-source function to the continuum one. The relationship between the departure and the magnetic field reveals an effect that the magnetic field induces an exponential increase in the level population of the lower level of Fe  i 6302.5 (Landé factor   g = 2.5  ) with the field strength. This indicates that the magnetic field can cause the redistribution of populations of those levels whose Landé factors are non-zero. Therefore, this effect should be included in the calculation of the statistical equilibrium. Secondly, an experiment utilizing the Hg5461 line in the laboratory on the Earth is carried out to reveal that the exponential relation is independent of variations in temperature, and the excitation is completely magneto-induced. Finally, the exponential relation is explained by taking account of the magnetic energy in the Boltzmann distribution.     

Magnetic susceptibility variations of the Edicaran cap carbonates in the Yangtze platform and their implications for paleoclimate

1 INTRODUCTION One of the most intriguing phenomena in the late Neoproterozoic (~750 to 543 Ma) is the globa occurrence of thin carbonates that directly overlie glacial deposits in almost every continent (Kennedy 1996; Hoffman et al., 1998; Hoffman and Schrag 2002; Brasier and Shields, 2000; James et al., 2001 Jiang et al., 2003; Nogueira et al., 2003). These “cap carbonates”, commonly several to tens of meters thick, have attracted enormous interests because o their unusually negati…     

The mineral chemistry of pyroxenite xenoliths in the volcanic rocks of Hoh Xil and their significance

The pyroxenite xenoliths in the volcanic rocks of Hoh Xil consist of clinopyroxenes and orthopyroxenes. The mineral composition of these pyroxenes is similar to that of mantle xenoliths including peridotite and pyroxenite from China and abroad, and different from that of granulites. The pyroxenes formed at 1101–1400°C (averaging 1250°C) and under 30–60 kb (averaging 46 kb). We deduced that the magma was derived from the mantle at a depth of more than 150 km, which fits in with the geophysical conclusion that the low-velocity layer existed in the mantle under 150 km.

     

地球化学景观吸引子的发现及其意义

勘查地球化学对异常评价的最大不确定性源于对地球化学景观特性的认识不够。我们应用构造相空间的方法分析了浙江儒岙幅（1:5万）水系沉积物测量的Ag含量数据，揭示了地球化学景观是具有低维吸引子（DZ≈2．9）的混饨系统。这一发现将对勘查地球化学中采样密度的选择、地球化学场模拟、异常评价等根本性问题产生重大影响。     

Faint galaxies: merging model of E/SO galaxies

We study a model of mergers affecting only the progenitors of present E/SO. We adopt the standard scenarios of star formation as prescribed by Guiderdoni & Rocca-Volmerange. The merging process is parametrized under the assumptions of(1) self-similarity of the Schechter MF and(2) mass conservation. Nine models are discussed. The predictions are compared with counts ofB _J ,U ⁺,F ⁺,N ⁺ bands. E/SO mergers account for the excess of the faintest blue galaxies without causing excess in redder bands. However, as we no longer have enough mergers at brighter magnitudes, a plain E/SO merging model fits less tightly for the redshift and the colour distributions. Detection effect, a steeper slope of LF may be ways to improve. Our models predict acceptable merger frequencies atz = 0.5 although some models predict more interacting galaxies than observation atz = 0.