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The hemicelluloses of Douglas firAbdurahman, Nizam January 1962 (has links)
The Douglas fir holocellulose was prepared by Wise’s(8) modification of Jayme's sodium chlorite procedure(9). The hemicelluloses were extracted using 24% potassium hydroxide followed by 17% sodium hydroxide containing 5% boric acid.
Meier(31) reported that barium hydroxide can be used to purify polysaccharide mixtures. The mode of action presumably being the formation of an insoluble complex with the cis-hydroxyl groups of the mannose or galactose integers. By using this method of purification Timell(30) isolated a galactoglucomannan from a 24% potassium hydroxide extract of eastern hemlock holocellulose. Following Timell's scheme the attempt to isolate a galactoglucomannan from Douglas fir did not proceed with the facility suggested. Two purifications by Meier's procedure failed to remove the xylose containing polysaccharide. Further batches of freshly prepared holocellulose were extracted and repeated attempts at the isolation and purification of a galactoglucomannan are at present being pursued.
The addition of barium hydroxide not only removed the galactoglucomannan fraction but also purified the xylan which remained in solution. Four barium hydroxide treatments followed by two purifications by means of Fehling's solution gave an arabino-4-0-methyl-D-glucuronoxylan freed from galactose. Previous attempts at the purification of this type of polysaccharide from softwoods have failed to remove the galactose residues.
A glucomannan fraction was extracted using 17.5% sodium hydroxide containing 5% boric acid. Four fractionations by the barium hydroxide procedure failed to remove the xylose residues. Two further fractionations via the copper complex removed the last traces of xylose but the fraction still contained about 8% galactose. This is not unusual for it has been reported that the majority of gymnosperm glucomannans contain at least 4% galactose. The glucose to mannose ratio is approximately 1:3.5 which is in the order of a true glucomannan.
It appears that the possibility should be seriously considered that the galactose residues present in the so called "glucomannans" are actually integral parts of these polysaccharides. Additional experimental data in the near future will undoubtedly serve to solve the problem. / Science, Faculty of / Chemistry, Department of / Graduate
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The anatomy of some important Taiwan woodsHwang, Shao-Kang January 1962 (has links)
A study was made of single wood samples from 35 species (27 genera and 16 families) of important Taiwan timbers. Results have been compared with information published by Kanehira in 1921 (30) and others (31, 44).
The anatomy of these woods is described in detail. A key based on microscopic features is included for identification. Descriptions follow standard terms of the International Association of Wood Anatomists
Two of the coniferous species, Pinus armandi Franch. and Chamaecyparis formosensis Matsum., and nine hardwood species Carpinus kawakamii Hay., Quercus gilva B1., Quercus longinux Hay., Cinnamomum camphora Nees., Cinnamomum randaiensis Hay., Lagerstroemia subcostata Koehne., Gordonia axillaris (Don.) Szysz., Trochodendron aralioides S. et Z., and Trema orientalis B1. had features similar to those reported (30, 31, 44).
Seven hardwood species, Alnus formosana (Burkill.) Makino., Quercus stenophylloides Hay., Engelhardtia formosana Hay., Beilschmiedia erythrophloia Hay., Cinnamomum micranthum Hay., Zelkova formosana Hay., and Tectona grandis Linn, f. showed different anatomical features from those recorded by Kanehira (30) and Kribs (31).
No previous description of wood anatomy has been found for seventeen species including Tsuga chinensis (French.) Pritz., Cunninghamia konishii Hay., Libocedrus formosana Hay., Chamaecyparis taiwanensis Masam. et Suzuk., Scheffera octophylla (Lour.) Harms., Castanopsis longicaudata Hay., Castanopsis stipitata Hay., Lithocarpus amygdalifolia Hay., Actinodaphne nantoensis Hay., Machilus arisanensis Hay., Machilus pseudolongifolia Hay., Machilus zuihoensis Hay., Cassia siamia Lam., Michelia formosana Mas., lllicium leucanthum Hay., Schima superba Gard. et Champ, and Ternstroemia gymnanthera Spr. All species treated in this study are described in more detail than occurs in past records.
Mass grouping of longitudinal parenchyma appears as a normal feature of Cunninghamia konishii Hay. This type of parenchyma distribution could be a taxonomic feature of Cunninghamia not previously described in the literature. / Forestry, Faculty of / Graduate
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Examination of cellulose-lignin relationships within coniferous growth zonesSquire, Gordon Balfour January 1967 (has links)
Lack of a selective holocellulose isolation procedure and the problem of limited material have long frustrated the attempts of wood scientists to accurately measure and describe carbohydrate yields within coniferous growth zones. A new method has been devised for micro-cellulose determination, Alpha-(formula omitted) cellulose yield maybe quantitatively estimated as the corrected yield of nitrated wood meal. Three - O.1 g wood meal samples provide a statistically reliable determination. A major limitation of the new technique, however, is that it cannot be applied to all woods.
Sixty positions within ten increments representing five Canadian coniferous woods of different genera were examined and intra-incremental patterns were constructed. Anova and Duncan's test showed latewood (formula omitted) -cellulose yield to be greater than that of earlywood by a highly significant degree. Alpha-cellulose content throughout mature growth zones was estimated reliably by linear correlation or, more accurately, by logarithmic transformation used in a recent mathematical model. The successful application of the latter is its first reported use describing the non-linear behaviour of a wood chemical property across a coniferous increment.
These patterns showed relationship of the long-chain carbohydrate fraction to seasonal development within coniferous growth zones. In addition, six of the ten patterns demonstrated new chemical evidence pertaining to a physiologically significant phenomenon in earlywood. Therein, minimum (formula omitted) -cellulose yield occurs at considerable cellular depth following cambial reactivation in the growing season. First-formed earlywood appears to retain some similarity at the chemical level of organization to last-formed tissues of the preceding season. Later-formed earlywood (i. e. , from the present year) does not appear to retain such similarity.
From earlier work of this laboratory, lignification patterns were described for the same materials, using ultraviolet measurements on acetyl bromide-acetic acid digestion products of two wood meal samples.
Examination of (formula omitted) -cellulose and lignification patterns provided evidence for their mutually exclusive behaviour. For the ten increments studied, the (formula omitted) -cellulose estimate (x̅ = 45.9 + 2.0%) was the exact complement of lignification (x̅ = 27. 4±1. 9%) at all positions but one. The linear regression for data from all increments was highly significant ( r = - 0.785). In addition, micro (formula omitted) -cellulose and micro lignin values, when combined, showed a definite tendency to cluster about a central value (x̅ = 73. 4 ± 1. 2%) suggesting that certain species require a common, critical measure of high molecular weight material. Dispersion about combined lignin and (formula omitted) -cellulose estimates was significantly less than about either of their individual means. This suggests much closer physiological control over the combination of these chemical entities, indicating that tree physiology is oriented more towards the finished bio synthetic product than towards the individual components involved in such a system. As a means of measuring successful nitrocellulose preparation, intrinsic viscosity (formula omitted) was used to indicate presence or absence of extensive degradation. Because of the highly variable at each position tested, no consistent trends in chain length were found across growth zones. However, in four increments, significant differences in (formula omitted) throughout the earlywood provided further evidence of two earlywood types. / Forestry, Faculty of / Graduate
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The chemical reactivity of thermo mechanical pulp (TMP) fibres : a detailed kinetic study of the reaction between fibre and isolated fractions of hollcellulose and cellulose with succinic anhydrideElias, Robert M. January 1994 (has links)
No description available.
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Isolation and identification of polyphenols of hemicellulose extractsTsai, Hsin-Chuan January 2011 (has links)
Digitized by Kansas Correctional Industries
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The application of photomicrographic techniques to problems of the pulp and paper industryBaldwin, Paul Clay 01 January 1940 (has links)
No description available.
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Organic and inorganic geochemistry of the petrification of woodSigleo, Anne Marguerite Colberg, 1944- January 1977 (has links)
No description available.
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The isolation and characterization of tissue fractions from the middle lamella and secondary wall of black spruce tracheids /Whiting, Philip. January 1981 (has links)
A method was developed for the isolation of tissue fractions from the middle lamella and secondary wall of black spruce (Picea mariana) tracheids. The concentrations of cellulose and glucomannan were found to be lower in the middle lamella tissue than in the secondary wall tissue, while the reverse was found for galactan and arabian. The content of glucuronoarabinoxylan was essentially the same in both morphological areas. The concentration of phenolic hydroxyl groups in the lignin in the two tissue fractions was determined by turbidimetric spectrophotometry and by pyrolytic gas chromatography. Secondary wall lignin was found to contain more than twice as many phenolic hydroxyl groups per phenylpropane unit as middle lamella lignin. The concentration of methoxyl groups in secondary wall lignin was 1.6 times the concentration in middle lamella lignin, indicating that about 40% of the lignin polymer in the middle lamella consisted of para-hydroxyphenyl residues. Most of the carbonyl groups in the lignin in wood were found in the middle lamella lignin. The carboxyl content of the middle lamella was about three times that of the carboxyl content of the secondary wall. Secondary wall lignin was more reactive towards chlorine, chlorine dioxide and sodium bisulphite. Secondary wall lignin was also more quickly dissolved than middle lamella lignin in kraft, acid-sulphite, and acid-chlorite pulping. The activation energies, towards kraft pulping, of middle lamella and secondary wall "bulk" lignin were found to be essentially the same. However, it was discovered that while most of the secondary wall lignin followed first order reaction kinetics, 70% of middle lamella lignin did not. It was also discovered that the majority of milled wood lignin originated in the secondary wall of the tracheid.
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The nature of the chemical constituents of grand fir bark (Abies grandis Lindl)Tokos, George Mike 25 October 1951 (has links)
Graduation date: 1952
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The isolation and characterization of tissue fractions from the middle lamella and secondary wall of black spruce tracheids /Whiting, Philip. January 1981 (has links)
No description available.
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