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#XRAY DIFFRACTION ANALYSIS SERIES#
The amorphous XRD profile is modeled using a Fourier series equation where the coefficients are determined using the nonlinear least squares method. This agrees well with cellulose I d-spacing measurements and oligosaccharide XRD analysis. It is hypothesized that short range order within a glucose unit and between adjacent units survives ball milling and generates the characteristic amorphous XRD profiles. It first examines the effects of ball milling on three types of cellulose and results show that ball milling transforms all samples into a highly amorphous phase exhibiting nearly identical powder X-ray diffraction (XRD) profiles. This paper addresses two fundamental issues in the peak deconvolution method of cellulose XRD data analysis: there is no standard model for amorphous cellulose and common peak functions such as Gauss, Lorentz and Voigt functions do not fit the amorphous profile well.
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