碱度对水热合成纤蛇纹石纳米管的影响研究   总被引：1，自引：0，他引：1  

李明  彭同江  马国华 《矿物岩石》2008,28(2):39-43

为克服天然纤蛇纹石纳米管在量子组装应用上存在的不易提纯、易被伴生矿物堵塞、管径不均等缺点,以活性MgO和纳米SiO2为原料,采用水热法在不同碱度下合成了系列纤蛇纹石样品.时合成样品的X射线衍射(XRD)、傅立叶红外光谱(FTIR)以及扫描电镜(SEM)分析表明,在200℃.pH值大于13的条件下反应60 h以上能够合成结晶度比较完善的纤蛇纹石;碱度的提高有利于纤蛇纹石氢氧镁石层和硅氧四面体层的生长,并促使两者结合更为紧密,晶胞参数b0值增大,结构层更易卷曲,纤蛇纹石的纤维管状结构更加完善,结晶度提高,纤维的晶体轮廓更加清晰,直径更为均一,长度增加;最后确认在200℃.pH 13.8,反应60 h条件下合成纤蛇纹石纳米管的直径约50 nm.长度多在600nm以上,长度上优于前人的合成.  相似文献   

微量石棉的X射线衍射定量检测   总被引：3，自引：0，他引：3  

张梅  高孝礼  黄光明  封亚辉 《岩矿测试》2010,29(3):309-312

微量(质量分数低至0.1%)石棉的定量分析是一世界性难题。研究了自行车、电动车车闸等摩擦材料中石棉含量为0.1%~5.0%(质量分数)的X射线衍射定量分析方法。对含有微量石棉的样品通过X射线衍射的基底吸收修正法,求出定量分析试样中的石棉含量,计算出石棉的比例。研究成果对支持我国自行车、电动车等产品出口日本的工作具有现实意义。  相似文献   

标准曲线法X射线粉晶衍射直接分析滑石中微量石棉     

薛雍  江向峰  钟玉锋 《岩矿测试》2010,29(3):322-324

以X射线粉晶衍射法为主要测试手段,结合偏光显微镜检查,配制了一套石棉含量为0.1%~1.5%(质量分数)的滑石样品作为参考标准,采用标准曲线法直接定量滑石中的微量石棉。结果表明,方法检出限低,重现性好,石棉样品的用量少,快速、有效。  相似文献   

一种绿色“斑马石”玉料的矿物组成研究     

燕唯佳  李立平  刘虹靓 《地质科学译丛》2013,(1):15-22

最近在江苏东海的水晶市场上出现了一种名为“斑马石一的玉石,该玉石总体颜色为墨绿色,其中有白色条纹呈带状分布并呈丝绢光泽。为了查明其组成,利用偏光显微镜、X射线粉末衍射仪、红外光谱仪、拉曼光谱仪以及激光诱导离解光谱仪等测试方法对该样品进行了测试分析。结果表明,该“斑马石”实际就是一种蛇纹石的集合体材料。其绿色部分的主要矿物组成为利蛇纹石,其次为绿泥石,白色部分由纤蛇纹石构成,含少量绿泥石,黑色包裹体为磁铁矿。这种材料不同于一般的蛇纹石玉,在于该玉石中含有一些定向的纤蛇纹石的平行纤维条带,正是这种纤维状平行排列的结构,导致了“斑马石”中呈丝绢光泽的条带。“斑马石”的折射率,相对密度及荧光特征与一般的蛇纹石玉无差异。  相似文献   

The sequence of geological events and the dynamics of the Milky Way galaxy     

Johann Steiner 《Australian Journal of Earth Sciences》2013,60(1):99-131

Present‐day galactic data permit the construction of a galactic model in which the galactic gravitational field is described by a gravitational function rather than the Newtonian gravitational “constant” G. The concept of this empirical gravitational function, which is based on galactic orbital velocity data, envisages G as a function of time and space. In this model the interaction of this gravitational function, which has rotational symmetry in the galactic plane, and the slightly elliptical galactic orbit of the solar system results in a systematic variation of G. This interaction specifies a simple galactic time‐scale which can be conveniently compared with events of the geological time‐scale. For reasons of galactic evolution and modifying effects due to suspected changes of mass distributions in the universe with the passage of time, which are classed here under the Dirac‐Jordan Effect, such a comparison is initially restricted to the past 1#fr1/4> cosmic years, or 350 million years. The problems in extending such a comparison to 8 cosmic years are discussed, and such an extension seems promising, but it is hampered by the paucity of geological and geophysical data from the lower Palaeozoic and the Precambrian and the present uncertainties in regard to galactic evolution.

“Worldwide” statistical maxima and minima of the following geological criteria disclose an episodic correlation with the variation of G and the rates of change of G during the past 350 million years, as specified by this galactic model. It is possible to interpret this correlation in terms of accepted geological principles and concepts in most cases. The following geological phenomena are considered in this comparison of the galactic and geological time‐scales for the past 350 million years.