Coniferous woods

Tall oil rosin is obtained from crude tall oil obtained from the Kraft (sulphate) pulping of various coniferous trees in the paper manufacturing industry. During the Kraft pulping process the fatty acids and the resin acids from the coniferous wood are saponified by the alkaline medium. On concentration of the resulting pulping liquor, the sodium soap of these mixed acids rises to the surface from where they are skimmed out. By acidification of this material with sulphuric acid, the crude tall oil is obtained. Fractional steam distillation of the crude tall oil allows the separation of the tall oil fatty acids and the tall oil rosins [21]. 

It was first artificially prepared by Tiemann from the glucoside coni-ferin, which occurs in the cambium of various coniferous woods. The constitution of vanUlin is that of methyl protocatechuic aldehyde—... 

Source Adapted from (i) Cell Wall Mechanics of Trecheids , M.R.E. London, Yale University, 1967, p. 169-170 (ii) A Microscopic Study of Coniferous Wood in Relation to its Strength Properties , H. Garland. Ann. Missouri Botan. Gard., 1939, 26, 1-95 (iii) Morphological Foundations of Fibre Properties , L.J. Rebenfeld, J. Polymer Sci., 1965, C9, p. 91-112). 

US military requirements and tests for wood pulp(sulfite) intended for manuf of NC are as follows(Ref 8) a)The material shall be bleached sulfite pulp from coniferous wood which has been washed to remove the purifying chemicals and formed into sheets or laps suitable for fluffing or shredding and subsequent nitration. 

Cross and Bevan Cellulose- An impure cellulose isolated from the complex it forms with lignin, in materials such as wood straw. The method of isolation is described by Doree (Ref 1) Ott (Ref 2). Cross Bevan cellulose contains both furfural-yielding substances (pentosans), and hexosans of the mannan type. It retains, in the case of coniferous woods, 40-60% of the total furfural-yielding substances in the original wood, and about 55 66% iq the case of hard woods. 

The ratio of vanillin to vanillic acid and the yields of these two products, expressed as percentages of wood lignin, are the most significant data available to judge the severity of an alkaline nitrobenzene oxidation of a coniferous wood. The yields of vanillin and vanillic acid reported in Tables IV and V as methyl ether and methyl ether ester are only approximately 8 and 50%, respectively, of amounts that might be expected based on previous work. The ratio of vanillin to vanillic acid has been found to be 8 1 whereas in the reaction reported here it is 1 2. Furthermore, Leopold 32) reported vanillin vanillic acid oxalic acid as 6 1 2 whereas... 

The body of a teenage girl was discovered in coniferous woods in the north of England. It had been wrapped in multiple large plastic bags that had... 

Galactans are found in association with other hemicelluloses in deciduous and coniferous woods, certain seeds and pectins. It is very difficult to obtain the pure polysaccharide. Not much is known of the detailed structure of these molecules,61 and few molecular weight measurements have been carried out. 

Fig. 1-6. Cells of coniferous woods. An earlywood (a) and a latewood (b) pine tracheid, an earlywood spruce tracheid (c), ray tracheid of spruce (d) and of pine (e), ray parenchyma cell of spruce (f) and pine (g) (llvessalo-Pfaffli, 1967).

Wood is converted into pulp by mechanical, chemical, or semichemical processes. Sulfite and kraft (sulfate) are the common chemical processes, and neutral sulfite is the principal semichemical process (NSSC). Coniferous wood species (softwoods) are the most desirable, but the deciduous, broad-leaved species (hardwoods) have gained rapidly in their usage and constitute about 25 percent of pulp-wood. Table 28.2 summarizes the conditions utilized with the various pulping processes,... 

Sugar yields from coniferous woods (softwoods) are about 50 percent at an average concentration of 5 percent. When fermented, the average ethyl alcohol yield per ton of drywoods is 50-60 gal and sometimes higher. 

It was formerly believed that coniferous woods contain a mannan. However, before the polysaccharide containing the mannose residues was isolated in a state of purity, Leech d and Anthis> were able to show that it was a glucomannan, by the isolation of disaccharides containing both glucose and mannose from a hydrolysate of polysaccharide material enriched in the mannose-containing material. This observation was later confirmed by the isolation of pure glucomannans from these woods. - ... 

The empirical nature of this fractionation may be appreciated by comparing the composition of a number of different preparations of alpha-cellulose. The alpha-cellulose from such coniferous woods as spruce, pine, and hemlock may contain appreciable amounts of mannan, although the xylan content is usually low. Similarly, the alpha-cellulose from hardwoods may contain appreciable quantities of non-cellulosic polyoses, although, in this case, the chief polyose is xylan, not mannan. 

A series of experiments has been undertaken with the view to determine hydraulic resistance of sunflower husks and sawdust of coniferous wood. 

VIII. Ae-Studies on Braun s Native Lignins from Coniferous Woods. Svensk Papperstidn. 61 187-210, 1958. 

A process to extract both oil and turpentine from coniferous woods. 

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