水稻叶片硅体与稻壳硅体的物相和光学性质比较

Phase and Optical Property Comparison of Silica Bodies in Rice between the Leaf and the Husk

研究了水稻成熟叶片和稻壳中硅体的物相、自发荧光、红外和紫外吸收特性。X-射线衍射结果和显微红外摄谱结果一致表明稻壳硅体结构单一,为典型无定型矿质S iO2。稻壳硅体在紫外激发下没有自发荧光,表明稻壳硅体不含酚类化合物,因此硅体在285 nm处的强烈吸收为稻壳硅体本身所为。叶片硅体结构变异较大,硅体与标准物质无定形硅矿质之间存在细微的差异,并且哑铃形硅体、扇形硅体和不规则硅体的红外吸收光谱也不尽相同,叶片中这3种硅体在紫外激发下都能够自发荧光,表明叶片硅体中含有酚类化合物。硅体混合物仅在290 nm处有微弱的吸收,显示出叶片硅体在结构和性质上的变异性和复杂性。

Silica bodies were isolated from the leaf and the husk of the rice. X-ray diffraction and micro-infrared analysis revealed that the structure of silica bodies from the husk is uniform. They are the same as the standard miner of SiO2. In the leaf, however, the structure of the silica bodies is more complex because there are three types of silica body. The fan silica body, the dumbbell silica body and the irregular silica body have different infrared absorption. The fluorescence microscopy indicated that there are phenols in silica bodies of the leaf because the bodies emitted auto-fluorescence under ultra-violet radiation whereas no such compounds were found in the silica body from the husk. Therefore, the strong UV absorption peak in 285 nm by the silica body from the husk was conducted by itself. A faint absorption in 290 nm by the silica body from the leaf demonstrates the variability and complexity in the texture and property.