cryst (version 0.1.0)

crystMW: Relative Crystallinity Calculation of X-Ray Diffraction Pattern of Starch by Bruckner Method

Description

Allow to calculate the relative crystallinity of starch by XRD. The basic concept of Bruckner approach involves obtaining a smoothed line that separates the amorphous and crystalline starch of an X-ray diffraction pattern. This smoothed line is achieved by applying a moving average smoothing method to the original pattern.

Usage

crystMW(pattern, N = 41, iter = 100)

Arguments

pattern

matrix. The matrix of X-ray diffraction pattern. The first row corresponds to Bragg angle 2$\theta$; the second row corresponds to intensity.

N

numeric. N length of the smoothing window (number of variables). Defaults to 41.

iter

numeric. Iter number of iterations. Defaults to 100.

Value

An object of class crystMW, which is a list with the following components:

Details

Calculate the relative starch crystallinity of XRD pattern by Bruckner method.

References

Bruckner, S. (2000). "Estimation of the background in powder diffraction patterns through a robust smoothing procedure." Journal of Applied Crystallography 33(3 Part 2): 977-979.

Examples

data(XRD)
# Convert data frame to matrix, select A-type starch
pattern <- as.matrix(t(XRD[,c("Bragg_angle","A")]))
# List of crystallinity components
crs <- crystMW(pattern, N = 41, iter = 100)
# Original matrix
original <- crs$original
# Background shape
background <- crs$background
# Curve of the crystalline starch
corrected <- crs$corrected
# Summary calculation of crystallinity
summary <- crs$summary