Western hemlock bark

Fig. 1. Thallium (3D plot, viewed from south) and Hg in dry western hemlock bark - Tsuius Creek, BC (Dunn Thompson 2009a).

The chemical reaction of western hemlock bark extract with... 

Catechin is among the principal polyphenolic monomers in white fir and western hemlock barks (10 JJLtJ ) Quercitin occurs in ponderosa pine bark, while dihydroquercitin is found in Douglas fir bark (16 17). The structure of these compounds are as follows ... 

The next series of reports based on use of bark for wet process hardboard were published over a 7-year span from 1950-1956 by Anderson and Runckel. In the first report (22), the results included laboratory boards made from Douglas-fir slabwood containing bark, which varied between 15 and 45% of the total furnish. Bending tests indicated adequate strengths were obtained, and addition of bark enhanced moisture resistance of the boards. Acceptable boards also were made when white fir and western hemlock barks made up a portion of the furnish. No binder was added to the Asplund-type fiber. 

Herrick, F.H. Chemistry and Utilization of Western Hemlock Bark Extractives. J. Agric. Food Chem. 28, 228 (1980). 

Hergert H L, von Blaricom L E, Steinberg J C, Gray K R 1965 Isolation and properties of dispersants from western hemlock bark. For Prod J 15 485-491... 

Herrick F W 1980 Chemistry and utilization of western hemlock bark extractives. J Agric Food Chem 28 228-237... 

Meyer R W, Kellogg R M, Warren W G 1981 Relative density, equilibrium moisture content and dimensional stability of western hemlock bark. Wood Fiber 13 86-96... 

Anderson A B, Wong A, Wu K-t 1975 Douglas-fir and western hemlock bark extracts as bonding agents for particleboards. For Prod J 25(3) 45-48... 

Steiner P R, Chow S 1975 Factors influencing western hemlock bark extracts use as adhesives. West For Products Lab Rept VP-X-153 Vancouver B C, 25 p... 

Domestic sources Eastern hemlock bark Western hemlock bark Tanbark oak Chestnut oak Black oak Chestnut wood Sumac leaves Foreign sources Quebracho heartwood Mangrove bark Wattle acacia bark) Myrobalan nuts Sicilian suma leaves... 

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