中文摘要：

弦长度分布（chord length distribution,简称CLD）可以用来描述几何对象（球形颗粒、柱状孔、薄片等）的大小、形状和空间排布等特点.原理上,弦长度分布正比于由小角散射所得的相关函数的二次微分,因此可以由相对散射强度进行计算.在结构研究中,将实验所得弦长度分布与理论计算某种确定几何体所得高度准确的弦长度分布进行比较,可以获知对象的特征几何结构.本文以中孔氧化硅分子筛为研究对象,介绍了弦长度分布的计算方法,以此精确计算了中孔分子筛的孔径分布,得到了分子筛表面有机官能化对孔径的影响规律.

英文摘要：

　Chord length distribution（CLD）could be used to describe the size,shape and arrangement of geometric figure,such as spheric particles,cylinder pore,thin sheets,etc.In principle,CLD is in proportion with the second derivative of correlation function obtained from small angle X-ray scattering（SAXS）and therefore can be calculated from the relative SAXS intensity.In structure research,the characteristics geometric information of particle can be obtained by comparing the experimental CLD from SAXS result and the theoretically predicted CLD with high precision.In this paper,with mesoporous molecular sieves as examples,the CLD method was introduced to calculate the size distribution of mesopores.The effect of surface organic functionalization of mesopores on pore size was also derived.