Decayed wood

Lead in building can be corroded by organic acids from new wood, decaying wood and lichens see Sections 9.3 and 18.10). This is a common phenomenon with run-off from lichens which grow on tiles and slates. Where this occurs, a sacrificial strip of lead has been advocated... 

Decayed wood is eventually converted to humus, a dark and amorphous form of organic matter in the soil, or, after very long periods of time (running... 

As stated previously, only about 3 % of the lignin content of sound wood was isolated by alcoholic extraction. It was therefore of interest to determine, whether increased amounts of lignin could be extracted from the decayed wood. Thus, both sound and decayed white Scots... 

Lignin from Sound Wood Lignin from Decayed Wood... 

Similar studies were conducted by Kudzin and Nord (64) on the hardwoods oak, birch and maple. The fungus employed to bring about the decay of these wood samples was Daedalea quercina. The results of the periodic analyses of the decayed wood and the chemical compositions of the alcohol extractable lignins are outlined in Tables 6 and 7 respectively. 

Mohebby, B. and Militz, H. (2002). Soft rot decay in acetylated wood. Chemical and anatomical changes in decayed wood. International Research Group on Wood Preservation, Doc. No. IRG/ WP 02-40231. 

Immunocytochemical Labeling. Antibodies were used as post-embedding markers. Sections of decayed wood were first incubated on a drop of TBS (Tris-phosphate saline buffer 0.1 M, pH 7.4, NaCl 0.15 M or 0.5 M), glycine... 

Thus, most of the degradative reactions of polymeric lignins suggested previously by the analysis of decayed lignin isolated from decayed wood by white-rot fungi were catalyzed by lignin peroxidase. 

P.-J. Maequer pointed out in his Dictionary of Chemistry (1778) that when plants are decomposed without combustion, acidic substances such as tartar and potassium acid oxalate are produced, that plants from which these acidic substances have been removed by extraction or distillation yield much less vegetable alkali than they otherwise would that by ignition tartar can be converted almost completely to this alkali (potassium carbonate) that the alkali in vegetable ash is therefore produced by the combustion of this acidic substance that decayed wood, in which the plant acids have been destroyed by fermentation, yields scarcely any alkali (as Boerhaave had observed) and that plants containing little or no acid yield on combustion little or no vegetable alkali (5). 

When an organism dies, it stops acquiring new carbon, and the amount of radiocarbon it contains begins to decline through radioactive decay. Wood from a tree that died (when felled for timber, say) 5,730 years ago has only half as much radiocarbon as that from a similar tree felled recently. Wood that is 11,460 years old... 

Li K, Geng X (2005) Formaldehyde-free wood adhesives from decayed wood. Macromol Rapid Commun 26 529-532... 

Order 4.— Tremellales.—Saprophytes which live on decaying wood as moist, soft, quivering, gelatinous growths becoming later dry and homy. 

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