Modelling the biomineralisation processes which form calcite coccoliths

生物矿化过程中最令人感兴趣的方面之一是生物体能够直接结晶以产生所需的晶相和晶体形状的方法。在以前的工作中，我们能够阐明氢氧化铁为基础的系统中的成核和晶体生长过程。我们希望将我们的方法应用于碳酸钙系统，特别是海洋颗石藻Emiliana Huxleyi如何能够产生锤状板状方解石单晶的问题，然后用于构建生物体周围的颗石层。我们的方法将涉及筛选含氧模板对碳酸钙体系的影响。这些模板被设计成用作多糖模板的各个部分的模型，多糖模板被认为在天然系统中指导球孢子的结构中是重要的。特别相关的是，我们观察到在水热条件下进行结晶使我们能够观察仍然包含模板的中间相，因此使我们能够建议模板如何影响某些晶体方向的生长，以产生（生物）的最终形状。该系统也将在标准条件下进行研究，以比较应用热液条件的效果，光的早期，成核事件可能在运作。

One of the most intriguing aspects of the process of biomineralisation is the means by which organisms are able to direct crystallisation to produce a desired crystal phase and crystal shape. In previous work we were able to shed light on both nucleation and crystal growth processes in iron hydroxide based systems. We wish to apply our approach to the calcium carbonate system and, in particular, to the question of how the marine coccolithophore, Emiliana Huxleyi, is able to produce single crystals of calcite in the shape of hammer-like plates which then are used to construct the coccosphere around the organism. Our approach will involve screening the effect that oxygen containing templates have on the calcium carbonate system. These templates are designed to serve as models for various parts of the polysaccharide template which is thought to be important in directing the structures of the coccoliths in the native system. Of particular relevance is our observation that performing crystallisations under hydrothermal conditions allows us to observe intermediate phases which still incorporate the template and therefore allow us suggest how the template affects growth in certain crystal directions in order to produce the final shape of the (bio)mineral. The systems will also be investigated under standard conditions both to compare the effects of applying hydrothermal conditions and also to shed light on the early, nucleating events which may be in operation.