有机质调控下企鹅贝及其附壳珍珠的珍珠层螺旋生长成核

采用环境扫描电子显微镜和高分辨透射电镜对海南三亚企鹅贝及其附壳珍珠不同部位的结构特征进行研究,并配合稀盐酸(0.5%)和EDTA试剂对样品进行脱钙处理。研究结果表明,该地区海水成因的珍珠层中有机质薄膜对珍珠层的螺旋生长成核和结晶取向起到了严格的调控作用,它为文石或方解石晶体的生长提供一个有效的定位或成核中心;有机质与文石微晶在时间和空间上的螺旋交互生长具有周期性,从而产生珍珠层表面的这种结构形态。企鹅贝珍珠层的形成归因于层间有机质薄膜的初始螺旋成核作用;有机质薄膜直接诱导了文石晶核的形成并调控珍珠层螺旋生长,促使文石微片晶与有机质膜螺旋有序交生,控制文石晶体的结晶取向和组装方式,并导致螺旋生长层的形成。

Spiral Nucleating Growth of Nacreous Layer on Pteria Penguin and Blister Pearl Controlled by Organic Matrix

The surface morphology of the nacreous layer on different parts of Pteria Penguin and blister pearl from Sanya, Hainan Province, are observed directly by using environmental scanning electron microscope. The samples are dipped in hydrochloric acid (0.5%) and EDTA for part or complete decalcification. The results indicate that the organic film in the nacreous layer rigorously controls the spiral nucleating growth and orientation of crystallization, which offers an effective growth centre for the growth of aragonite or calcite crystallite. As a result, the spiral growth structure of nacreous layer is produced by the periodically alternative growth of aragonite and organic matrix in the time and space. The formation of the nacreous layer of Pteria Penguin results from the initial spiral nucleating growth controlled by the organic film. The organic film directly induces the nucleating of aragonite crystallite to be spiral growth in the nacreous layer, that makes aragonite and organic matrix grow alternatively , and controls the orientation of crystallization and the mode of self-assembly of aragonite crystallite and finally results in the formation of the spiral growth layer.