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Cottonwoods

West Vaco 6475 cottonwood. 10 primarily for pulp with... [Pg.42]

Because of the plasticizing action of the resin-forming materials, the wood can be compressed under considerably lower pressures than dry, untreated wood. For example, treated spmce, cottonwood, and aspen veneer, dried to a moisture content of 65 but not cured, are compressed, when subjected to a pressure of only 1.72 MPa (- 17 atm) at 149°C, to about half the original thickness and a specific gravity of - 1.0. [Pg.330]

Phytodegradation Soils, groundwater, landfill leachate, land application of wastewater Herbicides (atrazine, alachlor) Aromatics (BTEX) Chlorinated aliphatics (TCE) Nutrients (NO, NH4+, PO3) Ammunition wastes (TNT, RDX) Phreatophyte trees (poplar, willow, cottonwood, aspen) Grasses (rye, Bermuda, sorghum, fescue) Legumes (clover, alfalfa, cowpeas)... [Pg.550]

Mature phreatophyte trees (poplar, willow, cottonwood, aspen, ash, alder, eucalyptus, mesquite, bald cypress, birch, and river cedar) typically can transpire 3700 to 6167 m3 (3 to 5 acre-ft) of water per year. This is equivalent to about 2 to 3.8m3 (600 to 1000 gal) of water per tree per year for a mature species planted at a density of 600 trees per hectare (1500 trees per acre). Transpiration rates in the first two years would be somewhat less, about 0.75 m3 per tree per year (200 gal per tree per year), and hardwood trees would transpire about half the water of a phreatophyte. Two meters of water per year is a practical maximum for transpiration in a system with complete canopy coverage (a theoretical maximum would be 4 m/yr based on the solar energy supplied at latitude 40°N on a clear day). [Pg.557]

Influence of Metal Ions on Oxygen Chemisorption and Ignition of Chars. We have carried out extensive studies of the influence of metal ions in wood on pyrolysis mechanisms (5.6) and this approach has now been extended to oxygen chemisorption of the chars. The metal ions occur in wood predominantly as the counterions of the uronic acid components of the hemicelluloses (12). We have shown that they can be almost completely removed by very mild acid treatment without any other major change in the chemistry of the wood. Table II shows that the major metal ions in cottonwood are Ca, K and Mg. The acid-washing process removed 98X of the metal ions in... [Pg.366]

Table II. Metal Ion Content (ppm) of Cottonwood and Acid-washed Cottonwood... Table II. Metal Ion Content (ppm) of Cottonwood and Acid-washed Cottonwood...
Figure 2. Pyrolysis - chemisorption - oxidation of cottonwood. (Reproduced with permission from Ref. 19. Copyright 1989 Elsevier Scientific Publishing Company, Inc.)... Figure 2. Pyrolysis - chemisorption - oxidation of cottonwood. (Reproduced with permission from Ref. 19. Copyright 1989 Elsevier Scientific Publishing Company, Inc.)...
Effect of Acid-washing and Ion-exchange on Oxygen Chemisorption and Ignition of Cottonwood Chars... [Pg.371]

Table V. Effect of Metal Ions on the Minimum Ignition Temperature (in Oxygen) of Cottonwood Chars... Table V. Effect of Metal Ions on the Minimum Ignition Temperature (in Oxygen) of Cottonwood Chars...
Sustained average yields from hybrid poplar NE-388 in Central Pennsylvania, have reached 21.3 oven dry tonnes per hectare, with 0.37 square metres per plant, the first harvest after one year, followed by five harvests at two-year intervals ( 7). Table IV shows yield experience for hybrid cottonwood (from the poplar family) in Canadian and American locations (8a-8f). Anderson and Zsuffa ( ) conducted growth tests on 35 different hybrid poplar clones at Kemptville, Ontario. With 0.25 square metres per plant, and harvesting after 2 years, they obtained yields of 4.9 to 19.3 oven dry tonnes per hectare year, with an average of 10.3 for the 30 clones that survived. Research is continuing into factors required for maximum yield. [Pg.138]

Yield Data for Hybrid Cottonwood Adapted from Reference (8)... [Pg.139]

Anderson, H.W., Zsuffa, L., Yield and Wood Quality of Hybrid Cottonwood Grown in Two-Year Rotation, Ontario Ministry of Natural Resources, Division of Forests, Forest Research Branch, Toronto (1975). [Pg.163]

Table IV. Mn of Black Cottonwood Alkali Lignin Fractions in Different Solvents and at Several Temperatures... Table IV. Mn of Black Cottonwood Alkali Lignin Fractions in Different Solvents and at Several Temperatures...
Table VI. LALLS Results on Acidic Organosolv Lignin Fractions from Black Cottonwood... Table VI. LALLS Results on Acidic Organosolv Lignin Fractions from Black Cottonwood...
Alkali Lignin. Black cottonwood platelets were cooked in a flow-through reactor with 1.0N NaOH at 160°C flowing at a steady rate of about 17.5 ml.min-1 (3). The effluent was collected as several successive fractions from which lignin was precipitated and purified (3). The same procedure was applied, at 170°C, to spruce matchsticks. [Pg.148]


See other pages where Cottonwoods is mentioned: [Pg.33]    [Pg.45]    [Pg.320]    [Pg.321]    [Pg.322]    [Pg.323]    [Pg.157]    [Pg.118]    [Pg.118]    [Pg.556]    [Pg.556]    [Pg.362]    [Pg.362]    [Pg.363]    [Pg.364]    [Pg.367]    [Pg.367]    [Pg.367]    [Pg.367]    [Pg.367]    [Pg.372]    [Pg.373]    [Pg.374]    [Pg.114]    [Pg.193]    [Pg.163]    [Pg.42]    [Pg.543]    [Pg.71]    [Pg.81]    [Pg.148]   
See also in sourсe #XX -- [ Pg.138 , Pg.139 ]

See also in sourсe #XX -- [ Pg.208 , Pg.243 ]




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