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Wood is a structural tissue/material found as xylem in the ... secondary cell walls, composed ... to extract various components from wood, or alternatively to modify ...
Wood chemistry, whose primary focus is the analysis of the chemical constituents comprising wood, with specific emphasis on cellulose, lignin, hemicelluloses, and extractives, as well as on the various products derived from these components. It is also explores potential uses for pulp and paper production, the utilization of wood and wood waste ...
The first lignified secondary walls evolved 430 million years ago, creating the structure necessary for vascular plants. The genes used to form the constituents of secondary cells walls have also been found in Physcomitrella patens. This suggests that a duplication of these genes was the driver of secondary cells wall formation. [2]
The wood moisture content is above 25% on a dry-weight basis; The environment is sufficiently warm; Oxygen (O 2) is present; Wood with less than 25% moisture (dry weight basis) can remain free of decay for centuries. Similarly, wood submerged in water may not be attacked by fungi if the amount of oxygen is inadequate. Fungi lumber/timber ...
Spalting is divided into three main types: pigmentation, white rot, and zone lines.Spalted wood may exhibit one or all of these types in varying degrees. Both hardwoods and softwoods can spalt, but zone lines and white rot are more commonly found on hardwoods due to enzymatic differences in white rotting fungi.
The database thousands of wood anatomical descriptions and nearly 66,000 photomicrographs of contemporary woods, along with more than 1,600 descriptions and 2,000 images of fossil woods. [ 16 ] Another very important database for wood anatomy, is the so-called, Delta Intkey .
The by-products from the wood processing industry are called wood processing residues and consist of cut offs, shavings, sawdust, bark, and black liquor. [27] Wood processing residues have a total energy content of 5.5 EJ annually. [28] Wood pellets are mainly made from wood processing residues, [m] and have a total energy content of 0.7 EJ.
Cement bonded composites are made of hydrated cement paste that binds wood, particles, or fibers to make pre-cast building components. Various fiberous materials, including paper, fiberglass, and carbon-fiber have been used as binders. Wood and natural fibers are composed of various soluble organic compounds like carbohydrates, glycosides and ...