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371.
372.
Treatment with metallic copper for the removal of elemental sulfur from bitumen extracted from sedimentary rocks or petroleum is the most widely used method. Little attention has been paid, however, to its disadvantages. It was observed that copper can interact with some polar organic substances during conventional sulfur removal, which can strongly influence the quantitative and qualitative determination of bitumen, as has been confirmed by interaction of long-chain fatty acids with copper. The copper soap generated was analyzed by element analysis, inductively coupled plasma optical emission spectrometry (ICP-OES), thermal analysis (TG-DSC) and Fourier Transform Infrared spectroscopy (FFIR). Mechanism of the interaction was investigated and elucidated. Our experimental results would necessitate improvement of the present method for sulfur removal and/or a search for a new one. 相似文献
373.
岩石中的渗透率、流体流动及热液成矿作用 总被引:4,自引:0,他引:4
热液成因的固体金属矿床形成过程中都曾拥有一段流动的历史。成矿物质以溶液的形式从矿源地穿过孔隙或断裂达到了现在的栖身之所,在此过程中流体通过的路径决定了它们的走向,而溶液本身也改变了路径的特征。因此,对于此类矿床的研究不能仅仅囿于眼之所见,而应将古流体流动的观念融入其中,并考察它们的跋涉之路。文中总结了近年来国内外在岩石孔隙、断裂介质及与其相关渗透率对热液成矿作用的控制等领域的研究成果和最新进展,对岩石渗透率、渗透率的影响因素、岩石中流体流动的特征等问题进行了阐述,讨论了渗透率对于热液成矿作用深度、成矿规模、矿质沉淀机制等方面的重要影响,藉此在固体金属矿床研究中强化流"体运动"的观念,并促进构造地质学和成矿作用地球化学间一个新研究方向的发展。 相似文献
374.
SOHO/MDI magnetograms are used to analyze the time variations in the magnetic parameters of the active region (AR) NOAA 10486, which was part of a large activity complex that passed over the solar disk from October 26 to 31, 2003, during solar cycle 23. The results are compared with X-ray flares in the AR and the parameters of coronal mass ejections associated with the AR. The time variations in the distributions of themagnetic-field strengths associated with the total magnetic flux (Fa), the flux imbalance between the northern and southern polarities (Im), the complexity of the field, as a measure of the mutual overlapping of the opposite polarities (Co), and the tilt angle of the magnetic axis (An) are considered. The time variations in the free energy accumulated in current sheets of ARs were traced using a parameter introduced for this purpose (Sh). The following results were obtained. First, the parameters Fa, Im, Co, An, and Sh quantitatively describe the current state of the AR and can be used to trace and analyze the dynamical evolution of its magnetic field. Second, variations in the magnetic-field-strength distributions and the mean values of Fa, Im, Co, An, and Sh are associated with flares and coronal mass ejections, and the variations have considerable amplitudes. Third, the parameter Sh characterizing the degree to which the magnetic field is non-potential in regions adjacent to the main neutral line increases before eruptive events, and is thus particular interest for monitoring the states of ARs in real time. Fourth, the magnetic field of the AR manifests a sort of quasi-elasticity, so that the field structure is restored after active events, on average, within 1–3 h. 相似文献
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The Anzishan ophiolite, a typical ophiolitic block of early Carboniferous age in the Mian-Lue suture zone of the Qinling Mountains, central China, consists of amphibolites/metabasalts, gabbros and gabbroic cumulates. All of these rocks, as well as those in the Hunshuiguan-Zhuangke (HZ) block, have compositions similar to normal MORB and back-arc basin basalts (BABB) with high εNd(t) values, indicating that they were derived from a depleted mantle source. The Mian-Lue suture zone also contains blocks of other lithologies, e.g., rift volcanic rocks in the Heigouxia block and arc volcanic rocks in the Sanchazi block. Although they are in fault contact with each other, the presence of these different blocks in the Mian-Lue suture zone may represent a complete Wilson cycle, from initial rifting to open ocean basin to final subduction and continent-continent collision, during the late Paleozoic-early Triassic. In this region, the North and South China Cratons were separated by Paleo-Tethys at least until the early Carboniferous, and final amalgamation of both cratons along the Qinling orogenic belt took place in the Triassic. 相似文献
379.
380.
Mechanism for the rapid motion of the Qianjiangping landslide during reactivation by the first impoundment of the Three Gorges Dam reservoir, China 总被引:10,自引:6,他引:4
Fawu Wang Yeming Zhang Zhitao Huo Xuanming Peng Shimei Wang Shintaro Yamasaki 《Landslides》2008,5(4):379-386
The first impoundment of the Three Gorges Dam reservoir in China started from a water surface elevation of 95 m on June 1,
2003 and reached 135 m on June 15, 2003. Shortly after the water level reached 135 m, many slopes began to deform and some
landslides occurred. The Qianjiangping landslide is the largest one; it occurred on the early morning of July 14, 2003 and
caused great loss of lives and property. Field investigation revealed that, although failure occurred after the reservoir
reached 135 m, the stability of the slope was already reduced by preexisting sheared bedding planes. To study the mechanism
of the rapid motion of this reactivated landslide, two soil samples were taken from a yellow clay layer and a black silt layer
in the sliding zone, respectively, and a series of ring shear tests were conducted on the samples. One series of ring shear
tests simulates the creep deformation behavior, while the other series simulates different shear rates. Conclusions drawn
from analysis of the ring shear tests indicate that the mechanism of the rapid motion of the reactivated landslide was caused
by the rate effect of the black silt layer during the motion phase after the creep failure. The yellow clay layer did not
play any important role in the rapid motion in the 2003 event. 相似文献