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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 #318225

Title: Cotton micronaire measurements by small portable near infrared (nir) analyzers

Author
item ZUMBA, JIMMY - Oak Ridge Institute For Science And Education (ORISE)
item Rodgers Iii, James

Submitted to: Applied Spectroscopy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/14/2015
Publication Date: 5/16/2016
Citation: Zumba, J., Rodgers III, J.E. 2016. Cotton micronaire measurements by small portable near infrared (nir) analyzers. Applied Spectroscopy. 70(5):794-803.

Interpretive Summary: A key quality and processing parameter for cotton fiber is micronaire, which is a function of the fiber’s maturity and fineness. Near Infrared (NIR) spectroscopy has previously shown the ability to measure micronaire, primarily in the laboratory and using large, research-grade laboratory NIR instrumentation. International interest has been expressed by the industry in the measurement of fiber micronaire using small, portable NIR spectroscopy instruments for both laboratory and outside the laboratory (e.g., field or greenhouse) locations. New, very small NIR micro-spectrometers have been commercialized that offer the potential advantages of smaller size and lower weight, lower cost, and increased portability over current portable units. A program was implemented to determine the feasibility of a small NIR micro-spectrometer to measure fiber micronaire both in the laboratory. In the laboratory, distinct spectral differences with increasing micronaire were observed. Optimal sampling and instrumental procedures and protocols were established. Comparative evaluations established very good method micronaire agreement between the micro-spectrometer and a standard portable spectrometer. The NIR micro-spectrometer measurements were fast (<1 minute per sample), required no sample preparation, and were easy to perform. The rapid and accurate laboratory measurement of fiber micronaire with a NIR micro-spectrometer was demonstrated.

Technical Abstract: A key quality and processing parameter for cotton fiber is micronaire, which is a function of the fiber’s maturity and fineness. Near Infrared (NIR) spectroscopy has previously shown the ability to measure micronaire, primarily in the laboratory and using large, research-grade laboratory NIR instrumentation. International interest has been expressed by the industry in the measurement of fiber micronaire using small, portable NIR spectroscopy instruments for both laboratory and outside the laboratory (e.g., field or greenhouse) locations. New, very small NIR micro-spectrometers have been commercialized that offer the potential advantages of smaller size and lower weight, lower cost, and increased portability over current portable units. A program was implemented to determine the feasibility of a small NIR micro-spectrometer to measure fiber micronaire both in the laboratory and outside the laboratory, with initial emphasis on laboratory measurements prior to moving to field evaluations. In the laboratory, distinct spectral differences with increasing micronaire were observed. Optimal sampling and instrumental procedures and protocols for two units (different spectral wavelength capabilities) were established. Comparative evaluations established very good method micronaire agreement between the micro-spectrometer and a standard portable spectrometer, with high Regression (R) value, low residuals, and few outliers (less than 20%). The NIR micro-spectrometer measurements were fast (<1 minute per sample), required no sample preparation, and were easy to perform. All end-state criteria were exceeded. The rapid and accurate laboratory measurement of fiber micronaire with a NIR micro-spectrometer was demonstrated.