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291.
A series of hydropyrolysis (HyPy) experiments have been conducted on a small suite of authentic polycyclic aromatic hydrocarbons (PAHs: coronene, pyrene and perylene) to investigate the HyPy behaviour of these PAHs. This information may help in the interpretation of the structural significance of aromatic HyPy products, often detected in high abundance, from high maturity kerogens. The PAHs were separately treated by HyPy and were all susceptible to some extent of hydrogenation. Perylene also decomposed into low molecular weight aromatics (e.g. methylbiphenyls). Structurally, perylene is much less stable than the more condensed PAHs coronene and pyrene. The total product concentrations (wt% of starting PAH) from all HyPy experiments were consistently less than 100 wt%, probably due to either the condensation of semi-volatile products on walls of the transfer line prior to reaching the HyPy trap or the inefficient cold trapping of highly volatile products. Hydrogenation of PAHs was prevalent and was found to be significantly influenced by the addition of a Mo-S based catalyst and potentially the C/Mo ratio, but largely independent of the two final temperatures used (520 °C and 550 °C). The fully aromatised and hydrogenated products for any stable ring system may provide a general indication of the size distribution of aromatic units within the kerogen structure. 相似文献
292.
在西昆仑盖山北坡恰尔隆-库尔浪-塔木铜多金属-金成矿带内,对产于下石炭统基性火山岩中的块状硫化物铜矿床和产于上石炭统酸性火山岩中的块状硫化物铜矿床的成矿条件,通过代表性矿床进行了对比分析.认为两者形成的地质构造环境相同,形成时间相近,空间上毗邻,矿化特征又极其相似,具有密切的内在成因联系数.结合成矿地质环境,铜金矿化蚀变信息提取图像上显示的色晕异常带与已知铜、金矿床和矿点的叠合程度,以及水系沉积物地球化学异常条件,进行铜矿成矿预测,认为该成矿带内的阿属河-木孜塔格-带是铜矿找矿的有望地区. 相似文献
293.
潮间带污泥中厌氧发酵产氢混合菌群组成与 Fe-氢酶基因多样性分析 总被引:1,自引:0,他引:1
以采自天津海水浴场潮间带的污泥为研究材料,将污泥热休克处理后富集混合菌群进行厌氧发酵产氢,测定混合菌群在发酵过程中累积产氢量和相关产氢指标(吸光度、酸碱度和氧化还原电位)的变化。结果表明,热休克处理后富集的产氢混合菌群产氢量为0.41mol H2/mol葡萄糖。产氢结束后,利用变性梯度凝胶电泳(DGGE)分析混合菌群组成和Fe-氢酶基因的多样性。混合菌群基因组DNA的16S rRNAV3区扩增产物经过DGGE电泳分离,结果得到6条丰度比较高的条带,测序结果表明优势菌为Clostridium sp.。利用梭菌氢酶基因保守性引物克隆混合产氢菌群中梭菌Fe-氢酶基因,扩增产物经DGGE电泳分离,电泳结果表明混合菌群中Fe-氢酶基因分为3个分类单元,NCBI-BLAST比对结果与Clostridium roseum和Clostridium perfringens的Fe-氢酶基因相似度分别为79%和98%。分析产氢混合菌群组成和Fe-氢酶基因多样性,可以为扩大产氢微生物种质资源奠定基础。 相似文献
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295.
胶东蓬莱金矿区流体包裹体和氢氧同位素地球化学研究 总被引:5,自引:2,他引:5
蓬莱地区金矿床以石英脉型为主,其次是蚀变岩型;成矿条件与著名的玲珑金矿床相似。金主要产于黄铁矿和多金属硫化物石英脉中。流体包裹体研究表明,金矿床中主要存在两种类型的流体包裹体:CO2-H2O包裹体和中低盐度的NaCl—H2O溶液包裹体。CO2-H2O包裹体气相以CO2为主,可含少量CH4、H2S、CO。其中,黄铁绢英岩的石英中含有丰富的CO2-H2O包裹体,而黄铁矿石英脉和多金属硫化物石英脉中富CO2与富H2O的CO2-H2O包裹体共存。显微测温结果显示,黄铁绢英岩中的CO2-H2O包裹体的均一温度范围为230℃~300℃;而黄铁矿和多金属硫化物石英包裹体的均一温度为220℃-390℃,鉴于这些包裹体是从不混溶的CO2-H2O流体中捕获的,因此它们的温度下限220℃~250℃左右,应该看作是它们的形成温度。成矿早期流体为富含挥发份(流体密度0.92~0.985g/cm^3)、中低盐度(4.15%~5.23%NaCleqv)的流体:到主成矿期逐渐演化为温度升高,盐度变化范围大(1.02%~15.5%NaCleqv),水溶液以NaCl为主,气体仍以CO2为主,但可含少量的CH4、H2S、CO及有机质等的流体(流体密度0.32~0.99g/cm^3);成矿期后的流体盐度、温度及CO2含量降至最低。本区矿床中石英的占δ^18O值变化在13.8‰-18.3‰,成矿流体的占δ^18O值在4、9‰-10.9‰之间,流体包裹体中占D变化范围很小,从-78‰变化到-101‰,主要集中在-78‰~-88‰之间。由此表明成矿流体以岩浆水为主,伴有大气降水的参与。在主成矿期成矿流体表现出明显的多期、多来源特征。温度降低和流体不混溶是导致金等成矿元素沉淀和富集的重要机制。 相似文献
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299.
The kinetics of hydrogen diffusion in enstatite was studied by hydrogen–deuterium exchange experiments in the range of 1–5,000 bar and 700–850°C using synthetic single crystals of pure and Cr-doped enstatites. The OH- and OD-content in the samples was quantified after each thermal treatment with Fourier transformed infrared spectroscopy. H–D-exchange rates were measured parallel to the three crystallographic axes. In addition, in order to visualize diffusion profiles, OH and OD were mapped for some samples, utilizing synchrotron IR micro-spectroscopy. Hydrogen self-diffusivities derived from D/H exchange experiments at one atmosphere are very similar to the chemical diffusivity of hydrogen in natural Fe-bearing orthopyroxene, which was reported previously (Stalder and Skogby 2003) to exhibit a small, but significant anisotropy (D[001] > D[100] > D[010]). Activation energies are estimated to be 211 (±31) kJ/mol for diffusion parallel [100] and 185 (±28) kJ/mol for diffusion parallel [010]. Lattice diffusion of hydrogen is decelerated by more than one order of magnitude when Cr is dissolved in enstatite. In comparison to the chemical composition, pressure seems to have only a minor influence on hydrogen diffusion. Compared to other minerals in the Earth’s upper mantle, enstatite exhibits the highest activation energy for hydrogen diffusion, suggesting faster diffusion than in other mafic minerals at mantle temperatures, but slower diffusion at crustal conditions. Thus under upper mantle conditions, physical properties that are expected to be influenced by hydrogen mobility, such as electrical conductivity, may in enstatite be more intensely affected by the presence of hydrogen than in other upper mantle minerals. 相似文献
300.