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101.
In this paper neutral point (coalescence) instability (NPI) of plasmoids (PMD) associated with tailward streaming O+, H+ and e− particles and diffusion region (spatial extent and particle life time) are studied. Also, radial and pitch angle diffusion
studies have been carried out in the near-earth region (10 and 11 RE during substorm onset. Our study revealed that coalescence instability is favoured by a heavier ion like O+ and the time required for a heavier ion to reach from one X point to an adjacent X point is minimum. Near an X type neutral
line (diffusion region) ions spend a fairly long time and gain a significant amount of energy. Radial and pitch angle diffusion
studies showed that higher energy particles are largely confined near the reconnection region (near-earth region) and lower
energy particles are rapidly depleted from the near-earth region during substorm onset. 相似文献
102.
黄铁矿中不可见金存在形式的实验研究—以冀东金厂峪金矿为例 总被引:3,自引:0,他引:3
不可见金存在于世界许多金矿的黄铁矿中。本文以冀东金厂峪金矿为例,对黄铁矿中不可见金的存在形式进行了多种实验方法的研究。黄铁矿金含量的多点分析和扫描电子显微镜实验研究表明,黄铁矿中不可见金大部分是呈链状排列的超显微金(粒度小于0.5μm的自然金)。黄铁矿的分步溶解实验、电子顺磁共振(EPR)及穆斯鲍尔谱研究证实黄铁矿中12.96%的不可见金以离子状态进入黄铁矿晶格代替Fe2 。 相似文献
103.
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106.
上地幔的岩石组构和各向异性 总被引:7,自引:1,他引:7
着重介绍了上地幔各向异性及其成因,研究内容和方法,各向异性研究的地球动力学意义,并强调指出橄榄石和辉石在塑性固态流动过程中产生的晶格优选方位或组构是导致上地幔各向异性最主要原因。 相似文献
107.
Arsenic fixation on iron-hydroxide-rich and plant litter-containing sediments in natural environments 总被引:2,自引:0,他引:2
Iron-hydroxide-rich and plant litter-containing sediments from natural sites contaminated with uranium mine tailing leachates were examined for their ability to adsorb arsenic. The samples with high contents of iron hydroxides (Fetotal concentration, >300 g kg−1) exhibited remarkable fixation of arsenic (up to 40 g As kg−1). This value corresponded approximately to the supersaturation point for natural iron hydroxides under the present conditions, and it was significantly lower than the value found for synthetic iron hydroxides. There was a strong correlation (R=0.8999) between the concentration of iron and that of arsenic at low arsenic contents, indicating adsorption on strong binding sites. Although all the samples had noticeable contents of organic carbon (plant litter), calcium, and manganese, no obvious effect of these elements on arsenic fixation could be detected. The amount of iron hydroxides was found the only fixation-controlling parameter immediately below a leaching water source. 相似文献
108.
The point source of neutral gas undergoing ionization and expanding into an uniform magnetic field is considered. Friction
between the neutral and ionized particles results in the formation of the magnetic field barrier and diamagnetic cavity surrounding
the source. At least one neutral point inevitably arises at the boundary of the cavity. When the neutral gas production rate
grows, two neutral points may arise at this boundary. In the vicinity of these points magnetic field lines converge, along
with the plasma flow which is magnetic field aligned in the steady state. As a result, two plasma jets originate from the
neutral points. Possible relation of these jets to cometary rays is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
109.
目前利用计算机绘制图形的软件很多,特别是作平面等值线图的软件,如SURFER、GRA-PHER等,但这些软件在平面上作图时均不考虑地质构造线,因此这些图件远不能满足地质工作者的需要。为此,本文为了解决上述问题从数学方法、原理方面作一简要说明,对于计算机处理过程作了较完整的叙述。 相似文献
110.