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P. Burtin Christian Jay-Allemand Jean-Paul Charpentier Gérard Janin 《Trees - Structure and Function》1998,12(5):258-264
Radial distribution of soluble phenolics was investigated at different heights in stems of Juglans nigra, J. regia and hybrids J. nigra 23 × J. regia. Four major phenolic compounds were studied: hydrojuglone glucoside (HJG), quercitrin (QUER) and two unknown compounds
characterized as two ellagic acid derivatives E1 and E2. HJG and E1 content increased gradually in the sapwood, peaked in
the sapwood-heartwood transition zone, and decreased drastically in the heartwood. QUER was accumulated preferentially around
the transition zone, and its content was relatively low in the outer part of the sapwood and in the inner part of the heartwood.
E2 content was low in the sapwood and increased in the heartwood. The heartwood formation was marked by the accumulation of
new soluble compounds. The relationship between wood extractives and wood colour were evaluated and discussed. HJG was considered
to be a major precursor of heartwood colour providing chromophores through hydrolysis (deglucosylation), oxidation and polymerization
processes.
Received: 2 September 1997 / Accepted: 23 November 1997 相似文献
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Edouard Machery Jean-Louis Dessalles Fiona Cowie Jason Alexander 《Biology & philosophy》2010,25(5):851-901
This symposium discusses J.-L. Dessalles's account of the evolution of language, which was presented in Why we Talk (OUP 2007). 相似文献
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