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The predictions of properties for wood disc average are seldom reported, and they are important for sorting out logs based on their quality. The minimum near infrared (NIR) spectra required to predict wood disc average properties would also be of critical importance. In this study, calibration and prediction models for wood disc average properties were developed using NIR spectral data for balsam fir (Abies balsamea (L.) Mill.) and black spruce (Picea mariana (Mill.) B.S.P.) samples collected from 14 different sites across Newfoundland, Canada. The calibration was done against area-weighted average wood properties determined by SilviScan. NIR spectra were collected in 18 mm increments from the radial-longitudinal face of green and oven-dried samples. Results showed that using NIR spectra from three spots per wood strip was sufficient for the modeling and prediction for density and module of elasticity (MOE). The coefficients of determination ranged from 0.76 (MOE of green wood samples) to 0.88 (density of oven-dried wood samples). However, the microfibril angle (MFA) cannot be well predicted from either green wood or oven-dried wood NIR spectra. Our results further showed that the NIR spectra collected from oven-dried wood samples gave better calibration and prediction than those collected from green wood samples. Resume: Les predictions des proprietes moyennes des disques de bois sont rarement presentees, bien qu'elles soient importantes pour trier les billes en fonction de leur qualite. Les spectres minimum dans le proche infrarouge (PIR) qui sont necessaires pour predire les proprietes moyennes des disques de bois ont aussi une importance cruciale. Dans cette etude, des modeles de prediction et de calibration des proprietes moyennes des disques de bois ont ete developpes a partir de donnees spectrales PIR d'echantillons de sapin baumier (Abies balsamea (L.) Mill.) et d'epinette noire (Picea mariana (Mill.) B.S.P.) preleves dans 14 sites differents couvrant l'ensemble de la province de Terre-Neuve, au Canada. La calibration a ete effectuee a partir des proprietes moyennes du bois determinees a l'aide de SilviScan et ponderees par la superficie. Les spectres PIR ont ete obtenus a tous les 18 mm le long de la face longitudinale-radiale d'echantillons verts et anhydres. Les resultats ont demontre que l'utilisation des spectres PIR provenant de trois points par barrette de bois etait suffisante pour modeliser et predire la densite et le module d'elasticite (MOE). Les coefficients de determination variaient de 0,76 (MOE d'echantillons de bois a l'etat vert) a 0,88 (densite d'echantillons de bois a l'etat anhydre). Cependant, les spectres PIR du bois vert ou anhydre ne sont pas adequats pour predire l'angle des microfibrilles (AMF). Nos resultats ont de plus montre que les spectres PIR des echantillons de bois a l'etat anhydre permettent d'obtenir une meilleure calibration et de faire de meilleures predictions que ceux des echantillons de bois a l'etat vert. [Traduit par la Redaction], Introduction There is considerable variability in wood fibers arising from differences in wood species, genetics, site conditions, geographic location, and position of the fibers in the tree (Kibblewhite et al. [...]

In order to evaluate reservoir characteristics and gas potential of organic-rich shale in Bottom-Lower Cambrian Hetang Formation and Upper Ordovician Xinkailing Formation, Xiuwu Basin, Jiangxi Province, Lower Yangtze Plate of China, researches regarding reservoir characteristics of organic-rich shale thickness, moderate burial depth, abundance and maturity of organic matter, fracturability, organic-matter pores and absorption performance have been conducted to Hetang Formation and Xinkailing Formation through field survey, shallow drilling, analysis to hydrocarbon-generation potential, scanning electron microscopy, measuring specific surface area and isothermal adsorption experiments. The results show that (1) Hetang Formation reservoir, although with extremely rich material basis, is of unfavorable hydrocarbon generation conditions due to late-stage thermal maturity, besides of undeveloped micropore structure, reservoir space development mainly by macroscopic crack, so further exploration should focus on locating favorable areas of low maturity and developed cracks, which is considered distributing in the core of Yanshan-Lingangshan-Shiziyan Mountains syncline; (2) Xinkailing Formation reservoir is of better organic matter abundance, pore development and absorption performance than Xinkailing Formation and hence further exploration should focus on surveying favorable areas of better sedimentary facies belt and stable structure for major breakthrough in shale-gas exploration, which is considered distributing in Wuning-Lixi and Jinkou-Tuolin areas. [ABSTRACT FROM AUTHOR]

An efficient separation technology for hydrolysates towards a full valorization of bamboo is still a tough challenge, especially regarding the lignin and lignin-carbohydrate complexes (LCCs). The present study aimed to develop a facile approach using organic solvent extraction for efficiently fractionating the main components of bamboo hydrolysates. The high-purity lignin with only a trace of carbohydrates was first obtained by precipitation of the bamboo hydrolysate. The water-soluble lignin (WSL) fraction was extracted in organic solvent through a three-stage organic solvent extraction process, and the hemicellulosic sugars with increased purity were also collected. Furthermore, a thorough characterization including various NMR techniques (31P, 13C, and 2D-HSQC), GPC, and GC-MS was conducted to the obtained lignin-rich-fractions. It was found that the WSL fraction contained abundant functional groups and tremendous amount of LCC structures. As compared to native LCC of bamboo, the WSL fraction exhibited more typical LCC linkages, i.e. phenyl glycoside linkage, which is the main type of chemical linkage between lignin and carbohydrate in both LCC samples. The results demonstrate that organic phase extraction is a highly efficient protocol for the fractionation of hydrolysate and the isolation of LCC-rich streams possessing great potential applications. [ABSTRACT FROM AUTHOR]