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The electrical conductivity of molten olivine is studied up to 3720K and 13.2 GPa. The results indicate that the electrical conductivity of molten olivine exhibits the perfect Arrhenius behaviour. The activation energy as well as temperature effect is much smaller than that of the solid olivine. It is expected that the high conductivity zone in the mantle is almost independent of the melting based on our experimental data. 相似文献
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The compression properties of Zr41Ti14Cu12.aNi10Be22.5, Zr44.4Nb7Cu13.5Ni10.8Be24.3 bulk metallic glasses and Ni77P23 binary amorphous alloy are investigated at room temperature up to 24 GPa, 39 GPa and 30.5 GPa, respectively, using in-situ high pressure energy dispersive x-ray diffraction with a synchrotron radiation source. The pressure-volume relationship of Ni77P23 amorphous alloy is consistent well with the second order BirchMurnaghan (B-M) equation within the experimental pressure range. However, under higher pressure, the experimental data of Zr-based specimens deviate from the B-M equation. Compare to the binary amorphous alloy less excess free volume existing in the bulk metallic glass and multi-component atomic configuration results in a two-stage relationship between compressibility and pressure. 相似文献
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测定了在高压条件下两种金属(钙和锌)的8 羟基喹啉络合物的晶体粉末样品的发光行为和原位X光衍射光谱.结果表明,压力对其发光性质产生极大的影响.随着压力的增加,8 羟基喹啉钙的发光强度在3 GPa以内时大大增加,随后发光强度快速下降,到7 GPa左右时几乎为零.而8 羟基喹啉锌的发光强度随压力的增加而逐渐降低,到7 GPa左右时约为常压的10%.高压下的原位X光衍射结果表明,8 羟基喹啉钙的晶体在3~4 GPa开始 发生非晶化相变,在7 GPa时该非晶化相变完成,样品的X光衍射完全消失.而8 羟基喹啉锌在压力的作用下(至16 GPa)没有发生明显的相变. 相似文献
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In situ high-pressure energy dispersive x-ray diffraction experiments on polycrystalline powder TiN with NaCltype structure have been conducted with the pressure up to 30.1 GPa by using a diamond anvil cell instrument with synchrotron radiation at room temperature. The experimental results suggest that an isostructural phase transition might exist at about 7 GPa as revealed by the discontinuity of V/Vo with pressure. 相似文献
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The crystal structure and electric properties of BaTiO3 nanocrystals are studied by in situ high-pressure synchrotron radiation x-ray powder diffraction. The phase transition takes place not only in the samples of BaTiO3 nanocrystals that are tetragonal phase with grain sizes more than 100nm, but also in the samples of BaTiO3 nanocrystals that are cubic phase with grain sizes less than 100nm. The pressures of phase transition are found to increase with decrease of the grain size from about 4 to 10GPa for crystallites ranging from 200 to 10nm in radius. The bulk moduli are calculated according to Birch-Murnaghan state equation before and after the phase transition. 相似文献