The 31P MAS-NMR spectrum showed a sing 31P intense resonance peak at -0.59 ppm with weak sidebands, corresponding to at least two types of phosphates.

• 31P核磁共振谱显示在-0.；59ppm处有一个强烈的共振峰和一些副峰；表明至少存在两种磷酸盐。