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ARS Home » Southeast Area » New Orleans, Louisiana » Southern Regional Research Center » Cotton Structure and Quality Research » Research » Publications at this Location » Publication #287166

Title: Split-replicates correlation of water content in cotton

Author
item Montalvo Jr, Joseph
item von Hoven, Terri
item Rodgers Iii, James

Submitted to: Textile Research Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/12/2013
Publication Date: 3/1/2014
Citation: Montalvo Jr, J.G., Von Hoven, T.M., Rodgers III, J.E. 2014. Split-replicates correlation of water content in cotton. Textile Research Journal. 84(4):435-445.

Interpretive Summary: The range of water content in U.S cottons brought into a state of balance at standard textile testing conditions is less than 1 %. This presents difficulty in obtaining accurate test data to calibrate fast sensors. A dozen raw cottons were analyzed for water by standard Karl Fischer Titration. This automated method uses an oven to warm the cottons, a carrier gas to transport the released water vapor into a bottle filled with an appropriate solution, and titrates the water with a special chemical. Factors that may influence the outcome such as number of replicates analyzed, blending, and the method of conditioning, standard room or chamber in the room with salt solution to control humidity, were studied. By splitting out either three sample replicates at one time or half the available number, split-replicates correlation within samples was used as the measure of relationship. The results depended on all factors studied. High split-half correlations were observed. This implies that good correlations are possible when mean water content is the dependent variable in associations with fast sensor data. This improved understanding of the correlation response to a specific set of conditions is important in understanding how to best apply methods to measure water in samples equilibrated to moisture equilibrium.

Technical Abstract: The range of water content in a set of cottons equilibrated to moisture equilibrium at standard textile testing conditions is < 0.8 %. This presents a challenge in obtaining accurate test data to calibrate fast sensors. A dozen raw cottons, nine American and three international, were analyzed for water by standard Karl Fischer Titration. The importance of the factors such as number of replicates analyzed, blending, and the method of conditioning – standard room or chamber in the room with salt solution to control humidity – were examined. Split-replicates correlation within samples, by splitting out either three replicates or half the available number, was used as the measure of correlation. The results depended on all factors studied. High split-half correlations were observed, which suggested that good correlations are possible when mean water content is the dependent variable in regressions with fast sensor data. This improved understanding of the correlation behavior is important for optimal application of methods to measure water in samples equilibrated to moisture equilibrium.