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Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants.It is an organic material – a natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin that resists compression.
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 ...
Its most commonly noted function is the support through strengthening of wood (mainly composed of xylem cells and lignified sclerenchyma fibres) in vascular plants. [17] [18] [19] Finally, lignin also confers disease resistance by accumulating at the site of pathogen infiltration, making the plant cell less accessible to cell wall degradation. [20]
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 ...
The oxidized metal elements that constitute wood ash are mostly considered alkaline. For example, ash collected from wood boilers is composed of [6] 17–33% calcium in the form of calcium oxide (CaO) 2–6% potassium in the form of potassium oxide (K 2 O) 2.5–4.6% magnesium in the form of magnesium oxide (MgO)
Wood ash from a campfire. Wood ash is the powdery residue remaining after the combustion of wood, such as burning wood in a fireplace, bonfire, or an industrial power plant.It is largely composed of calcium compounds, along with other non-combustible trace elements present in the wood, and has been used for many purposes throughout history.
The first artificial fibre reinforced plastic was a combination of fiber glass and bakelite, performed in 1935 by Al Simison and Arthur D Little in Owens Corning Company [16] One of the most common and familiar composite is fibreglass, in which small glass fibre are embedded within a polymeric material (normally an epoxy or polyester). The ...
Cellulose is a polymer made of repeating glucose molecules attached end to end. [4] A cellulose molecule may be from several hundred to over 10,000 glucose units long. Cellulose is similar in form to complex carbohydrates like starch and glycogen. These polysaccharides are also made from multiple subunits of glucose.