Impact of composition and local, bulk and surface structure of fibrous carbonates on their fabric and morphology

纤维状碳酸盐的组成以及局部、整体和表面结构对其织物和形态的影响

• 批准号: 218324714
• 负责人: Professor Dr. Hermann Gies
• 金额: --
• 依托单位: Institut für Geologie, Mineralogie und Geophysik
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/218324714?language=en
• 关键词: Impact; composition; local; bulk; surface

Although carbonates containing radiaxial fibrous and/or fasicular optical calcite cements are considered to be one of the best proxies for the geochemistry of ancient oceans, their formation and the structural origin of their unusual properties are only poorly understood. Therefore, in this project bulk and surface structure and composition of fibrous radiaxial calcites will be studied together with seed formation and growth conditions. Using crystallographic techniques such as the analysis of the crystal structure, globally and space resolved, and the analysis of the composition and structure of surfaces, a most complete relation of structure, composition and morphology will be obtained. The comparison of natural and synthetic (experimental) samples should allow for a rational understanding of processes involved. In crystal growth experiments also the question of rhythmic growth will be addressed. In particular the influence of changing composition of mother liquor on the morphology and composition of the crystal is of interest. All products will undergo crystallographic characterization. In addition, the influence of organic molecules such as amino acids, sugars, lignin etc. on the growth process will be studied considering micrite formation conditions. For an understanding of processes in atomic resolution, from model systems of large calcite crystals interacting with these organics, the structure of the surface including the organic add-layer will be analyzed using grazing incidence X-ray diffraction (GIXRD) and atomic force microscopy (AFM) experiments.

尽管含有透射纤维和/或高纤维光学方解石水泥的碳酸盐被认为是古代海洋地球化学的最佳代理之一，但它们的形成及其不寻常特性的结构起源只有知之甚少。因此，将研究纤维刻轴孔子的整体结构和表面结构以及种子形成和生长条件。使用晶体学技术，例如对晶体结构的分析，全球和空间的分析，以及对表面的组成和结构的分析，将获得结构，组成和形态的最完整关系。自然和合成（实验）样本的比较应允许对所涉及过程的合理理解。在晶体生长实验中，还将解决节奏生长的问题。尤其是，含母酒的组成对晶体的形态和组成的影响是感兴趣的。所有产品都将经历晶体学表征。另外，考虑到微铁形成条件，将研究有机分子（例如氨基酸，糖，木质素等）对生长过程的影响。为了理解原子分辨率的过程，从与这些有机物相互作用的大方解石晶体的模型系统中，将使用放牧X射线衍射（GIXRD）和原子力显微镜显微镜（AFM）实验分析表面的结构。