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1.
In the light of major element geochemistry, mineral chemistry and REE and isotopic data, the small but apparent isotopic differences between the Cenozoic volcanic rocks east and west of the Tancheng-Lujiang fault are believed to be caused by the mixing and metasomatism of crustal and mantle material in tho mantle source region in response to Pacific plate subduction. The presence of phlogopite and pargasite in mantle xenoliths lends strong support to mantle metasomatism.  相似文献   
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High pressure/temperature annealing experiments are used to determine diffusivities of H+ and D+ in non-stoichiometric spinel, a low-pressure analogue for nominally anhydrous minerals in Earth’s mantle. Data are fitted to the following Arrhenius law: Diffusivity (m2/s)?=?4?±?1?×?10?12 exp(?54?±?2 kJ?mol?1/RT). At low temperatures, H+ and D+ diffusion in non-stoichiometric spinel is charge balanced by flux of O vacancies, with infrared data consistent with protonation of both octahedral and tetrahedral O–O edges in non-stoichiometric spinel, and additional fine structure due to Mg–Al mixing and/or coupling of structurally incorporated H+ with cation vacancies. Absence of changes in the fine structure of O–H absorption bands indicates that H+ can become locally coupled and uncoupled to other defects during bulk diffusion. As such, proton conductivity in spinel group minerals, arising from faster flux of uncoupled H+, can only be calculated from H+ mobility data if the extent of defect coupling is constrained.  相似文献   
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In this study, scallop mantle protein was treated by ultrasound at different powers, and then analyzed by ANS fluorescent probes, circular dichroism spectroscopy, endogenous fluorescence spectrum, DNTB colorimetry and in-vitro digestion model to elucidate the structure–function relationship. The results indicated that ultrasound can significantly affect the secondary structure of scallop mantle protein like enhancing hydrophobicity, lowering the particle size, increasing the relative contents of α-helix and decreasing contents of β-pleated sheet, β-turn and random coil, as well as altering intrinsic fluorescence intensity with blue shift of maximum fluorescence peak. But ultrasound had no effect on its primary structure. Moreover, the functions of scallop mantle protein were regulated by modifying its structures by ultrasound. Specifically, the protein had the highest performance in foaming property and in-vitro digestibility under ultrasonic power of 100 W, oil binding capacity under 100 W, water binding capacity under 300 W, solubility and emulsification capacity under 400 W, and emulsion stability under 600 W. These results prove ultrasonic treatment has the potential to effectively improve functional properties and quality of scallop mantle protein, benefiting in comprehensive utilization of scallop mantles.  相似文献   
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分析了培养基中的小牛血清、贝血清、水解乳蛋白等几种天然成分和合成培养基TC199对中国马氏珠母贝外套膜组织细胞在体外的生长情况和珍珠质分泌功能的影响,并确定了它们在组成培养基时的适宜含量.其中,贝组织提取物、鸡胚汁对细胞的生长和珍珠质的分泌具有十分重要的作用;5%的小牛血清和10%的贝血清共同使用对维持细胞形促进细胞生长有很好的作用,但单独使用则有一定的负作用.  相似文献   
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本文针对电测法对高炉炉壳进行应力应变现场实测中的许多技术问题。进行了电测技术的若干技术问题的研究。解决了测试中由于停封取芯而导致的电测导线断开,而确保测试的连续性问题,采取了有效的防潮措施;选用了合适的应变计和粘结剂问题,通过模拟实验及现场实测证明了所采取的技术措施是有效的,使电测法在高炉炉壳检测中的应用得到进一步的完善。  相似文献   
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A. P. Jones  H. Sawamoto 《高压研究》2013,33(1-6):726-728
Abstract

We have determined the solidus for mantle peridotite with excess water. The solidus is important for prediction of temperature and depth of melting. Our results give slightly higher temperatures than predicted by extrapolation from lower pressure piston cylinder data. Melting may be restricted to shallower depths than previously expected.  相似文献   
8.
To assess the ability of densimetry for CO2 fluid in CO2 inclusions, we compare two methods, microthermometry and Raman microspectroscopic densimetry for CO2. The comparative experiment was performed for nine CO2 inclusions in three mantle xenoliths. The results are as follows: (1) microthermometry precisely determines CO2 density with the range of 0.65 to 1.18 g/cm3 compared with Raman microspectroscopic densimetry; (2) CO2 density obtained by Raman microspectroscopic densimetry is fairly consistent with that by microthermometry; (3) it is hard to determine CO2 density in CO2 inclusion with diameter of less than around 3 µm using microthermometry; and (4) microthermometry can be applied only to the CO2 inclusion whose CO2 density ranges from around 0.65 to 1.18 g/cm3, whereas the Raman microspectroscopic densimetry is applicable to CO2 density ranging from 0.1 to 1.24 g/cm3. The above features carry the potential for estimation of depth origin of mantle‐derived rocks. The depth where the rocks were trapped by host magma can be estimated using both geothermometric data and CO2 fluid density in CO2 inclusions in the rocks. Typical precisions of density of CO2 in CO2 inclusions obtained by the Raman microspectroscopic densimetry (~0.01 g/cm3) and by the microthermometry (< 0.001 g/cm3) correspond to uncertainties in the depth origin of 2.4 km and < 1.7 km, respectively, at 1000 ± 50 °C. In case of the mantle under 750–1250 °C and 1 GPa, the CO2 fluid has a density ranging from 1.06 g/cm3 to 1.21 g/cm3, which are well measured by the Raman microspectroscopic densimetry. Combination of both densimetries for CO2 in mantle minerals elucidates the deep structure of the Earth. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
9.
The relationship between Mg# [ = 100 Mg/(Mg + Fe) in mol] and the Raman shift was analyzed precisely for olivine [(Mg, Fe)2SiO4] samples with Mg# between 100 and 62.8. Two prominent peaks at 826–820 cm−1 (peak 1) and 858–849 cm−1 (peak 2) and three subordinate peaks at 883–881 cm−1 (peak 3), 920–914 cm−1 (peak 4), and 967–951 cm−1 (peak 5) were observed to shift monotonously to lower wavenumbers with decreasing Mg#. The ΔMg#( = Mg#refMg#) versus Δν(= νref − ν) can be linearly regressed for each peak as ΔMg# = A Δν, where ν is a peak wavenumber of olivine with Mg# ranging from 100 to 62.8, and νref is that of olivine with a reference value of Mg#, namely, Mg#ref. We set Mg#ref as 100 (i.e.pure forsterite Mg2SiO4) whereas A is a regression parameter (5.789, 4.294, 12.34, 6.348, and 2.09, respectively,for peaks 1, 2, 3, 4, and 5). This equation enables us to avoid small inter‐laboratory differences of wavenumber calibration. The equation for peak 2 yields estimations of Mg# in geologically satisfactory precision, ± 1 Mg# (1σ) in the Mg# range of 100–62.8. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
10.
模拟实验是当前地幔对流研究中的一个重要手段,一个重要组成部分。本文着重介绍近年来关于地幔热对流模拟实验研究发展概况。从相似参数出发,讨论了实验装置,测试手段,并对实验结果和今后发展趋势作了评述。   相似文献   
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