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Distribution of Lignin

The value of kML is likely to be in the vicinity of 1.7 for mature normal softwoods (Saka et al. 1982). However, compression (Westermark 1985) and juvenile woods (Donaldson and Ryan 1987) are reported to have a different correction factor. This may be due to the fact that such abnormal softwoods contain different types of lignins in both the secondary wall and middle lamella regions. [Pg.140]

By combining the bromination-EDXA technique with ultraviolet (UV) microscopy, it is possible to determine not only the distribution of lignin but also the distribution of guaiacyl and syringyl residues in various morphological regions (Saka et al. 1988, Saka and Goring 1988). [Pg.140]

Morphological region Tissue volume percentage (V.) Relative lignin ( cone. ( = k, —J Lignin cone, (g/g) [Pg.140]

Assuming the total X-ray counts of Br-Ka is the sum of the X-ray intensities from the brominated syringyl and guaiacyl lignins, then [Pg.141]

From Eqs. (2) and (3), the concentration of the syringyl and guaiacyl lignins in the wood cells are calculated from the expressions [Pg.141]

B. J. Fergus, "The Distribution of Lignin in Wood as Determined by Ultraviolet Microscopy," Ph.D. thesis, McGill University, Montreal, Canada,... [Pg.146]

Figure 3.4 Distribution of lignin in earlywood tracheids of black spruce. Figure 3.4 Distribution of lignin in earlywood tracheids of black spruce.
Table 3.2 Distribution of lignin in softwoods and hardwoods in the various morphological zones. Table 3.2 Distribution of lignin in softwoods and hardwoods in the various morphological zones.
Whatman filter paper 4 were examined for the distribution of lignin fractions (oligolignols), produced during the pretreatment. The results given in Table 4 at 0 time (uninoculated) indicated that the solubilized lignin just after pretreatment and prior to its fermentation with P. sajor-caju contained oligolignols of different MW. [Pg.307]

Forss, K. Kokkonen, R. Sagfors, P.-E. Determination of the Molar Mass Distribution of Lignins by Gel Permeation Chromatography ACS Symp. Ser. 1989, this volume. [Pg.48]

Determination of the Molar Mass Distribution of Lignins by Gel Permeation Chromatography... [Pg.131]

A method is needed for the determination of the molar mass and molar mass distributions of lignins. The method should give reproducible results when used in different laboratories. The procedure should not be complicated, and the calibration components must be readily available and reasonably priced. [Pg.131]

It has been shown that the molar mass distributions of lignin sulfonates and kraft lignin can be determined by gel permeation chromatography. Calibration of the columns with lignin sulfonates of known molar mass or, alternatively, with commercially available proteins and polypeptides has been shown to give the same result. [Pg.137]

Determinations of Average Molecular Weights and Molecular Weight Distributions of Lignin... [Pg.141]

TABLE 4-4. Distribution of Lignin in Spruce (Black Spruce, Picea mariana) Tracheid"... [Pg.80]

TABLE 4-5. Distribution of Lignin in Birch (White Birch, Betula papyrifera) Xylem ... [Pg.81]

TABLE 7 2. Distribution of Lignin in Kraft and Acid Sulfite Fibers of Spruce Earlywooda... [Pg.110]

Wood, J. R., and Goring, D. A. I. (1973). The distribution of lignin in fibres produced by kraft and acid sulphite pulping of spruce wood. Pulp Pap. Mag. Can. 74, T309-T313. [Pg.145]

Schuerch C (1952) The solvent properties of liquids and their relation to the solubility, swelling, isolation and fractionation of lignin J Am Chem Soc 74 5061-5067 Scott JAN, Procter AR, Fergus BJ, Goring DAI (1969) The application of ultraviolet microscopy to the distribution of lignin in wood Description and validity of the technique Wood Sci Technol 3 73 - 92... [Pg.19]

Fergus BJ, Goring DAI (1970) The distribution of lignin in birchwood as determined by ultraviolet microscopy Holzforschung 24 118-124 Fergus BJ, Procter AR, Scott JAN, Goring DAI (1969) The distribution of lignin in spruce wood as determined by ultraviolet microscopy Wood Sci Technol 3 117-138... [Pg.58]

Kojima Y, Yoon SY, Kayama T (1988b) A study of production of CTMP from hardwood Part 3 Characterization of pulps produced by CTMP O-i process J Jpn Tappi 42 953-962 Lange PW (1954) The distribution of lignin in the cell wall of normal and reaction wood from spruce and a few hardwoods Sven Papperstidn 57 525-532 Luft JH (1961) Improvements in epoxy resin embedding method J Biophys Biochem Cytol 9 409-414... [Pg.121]

Wood JR, Goring DAI (1971) The distribution of lignin in stem wood and branch wood of Douglas-fir Pulp Pap Mag Can 72(3) T95-T102... [Pg.132]

To determine the distribution of lignin from bromine analysis, it is essential to know the reactivity of bromine toward lignin in different morphological regions. For black spruce (Picea mariana), Douglas-fir (Pseudotsuga menziesii) and loblolly pine (Pinus taeda), the lignin in the secondary wall of tracheids is 1.7... [Pg.138]

Table 4.4.1 gives the distribution of lignin in Douglas-fir (Pseudotsuga menziesii) earlywood tracheids (Saka and Thomas 1982). The overall lignin content (W) of the earlywood portion is 0.285 gig). The Klason and acid-soluble lignin determinations should be made on wood taken near the location from which the sections are collected for EDXA measurements. [Pg.140]

Table 4.4.1. The distribution of lignin in Douglas-fir earlywood tracheids as determined by bromination with SEM-EDXA. (Saka and Thomas 1982)... Table 4.4.1. The distribution of lignin in Douglas-fir earlywood tracheids as determined by bromination with SEM-EDXA. (Saka and Thomas 1982)...
Table 4.4.2. The distribution of lignin in white birch as determined by TEM EDXA coupled with UV microscopy (Saka and Goring 1988)... Table 4.4.2. The distribution of lignin in white birch as determined by TEM EDXA coupled with UV microscopy (Saka and Goring 1988)...
See other pages where Distribution of Lignin is mentioned: [Pg.137]    [Pg.140]    [Pg.27]    [Pg.33]    [Pg.110]    [Pg.116]    [Pg.151]    [Pg.414]    [Pg.1110]    [Pg.79]    [Pg.79]    [Pg.82]    [Pg.82]    [Pg.6]    [Pg.18]    [Pg.19]    [Pg.43]    [Pg.43]    [Pg.43]    [Pg.120]    [Pg.122]    [Pg.133]    [Pg.133]    [Pg.140]   


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Classification and Distribution of Lignin

Distribution of Guaiacyl and Syringyl Lignins

Lignin distribution

Molar mass distribution of lignins

Of lignin

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