BLENDING OF COTTON FIBER SAMPLES FOR LENGTH MEASUREMENT

摘要

This experiment investigated the precision of laboratory sample-blending procedures for fiber length testing. It was built around a 2 x 2 x 2 cross-treatment design, comprising two sample-blending methods (hand blending and mechanical blending) and two specimen-extraction techniques (multiple pinch vs. single tuft) applied to two fiber forms (raw lint and sliver). In every case, a 10-gram blended sample was prepared. Each blended sample was exhausted by sequentially withdrawing twenty specimens of 0.5-grams each. All specimens were analyzed by the Advanced Fiber Information System (AFIS) length measurement instrument to determine the fiber length distribution. The experiment was replicated four times on each cotton tested. Variations in the completelength distributions by individual length interval, as well as the summary statistical properties were compared within methods (i.e., between samples) and within samples (i.e., between specimens). A proper choice of sample-blending and specimen-compositing approaches reduced the variation in length properties as measured by AFIS in raw cotton lint to approximately the level of variation obtainable directly from sliver. Mechanical blending was found to have reduced the random variation in mass determination of short fiber content (SFC) between 10-gram samples of raw lint from the same cotton bale by about a factor of two.