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AbstractIn this work, near infrared (NIR) and pyrolysis-molecular beam mass spectra (MBMS) of loblolly pine (Pinus taeda)were studied by means of generalized two-dimensional correlation spectroscopy in order to assign specific contributions of cellulose in the two spectral domains. Homo- and hetero-correlation techniques were employed to analyze the concentration-dependent spectral variations of cellulose. Specific bands of cellulose were assigned in the NIR and MBMS spectra, and moreover two masses m/zat 114 and 173, commonly assigned to cellulose fragments, were found to not originate from the pyrolysis of cellulose. [ABSTRACT FROM AUTHOR]

The time domain of 1H NMR spectroscopy allows straightforward editing of the T2 relaxation profiles in maritime pine wood. A new method from the Carr-Purcell-Meiboom-Gill sequence is proposed to measure the amount and distribution of water in wood, as well as the location of major dissolved organic materials. A general calibration model giving reliable and precise identification of these parameters is described. The method presented for editing T2 relaxation profiles (obtained by the Contin program) may be helpful in solving practical drying and gluing problems in the wood industry. It can be used for monitoring chemical modifications of wood fibers involved in the design of wood composite materials. [ABSTRACT FROM AUTHOR]

AbstractYellow poplar (Liriodendron tulipiferaL.) wood flour was chemically modified with acetic anhydride at varying times and initial moisture contents at a constant temperature. All samples exhibited increasing weight gains in the range of 5–16% with increasing reaction or treatment time. The acetylated poplar wood flour was characterized by means of Fourier transform infrared spectroscopy and near infrared (NIR) spectroscopy. Principal component analysis performed on the spectral data revealed clusters according to the esterification level. Partial least squares regression models developed from NIR data were able to predict the weight gain and the percentage of reacted OH groups. The correlations show that there is a direct and linear relationship between the spectra and the weight percentage gain and, therefore, the degree of acetylation. [ABSTRACT FROM AUTHOR]