Search results
Results from the WOW.Com Content Network
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.
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 .
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 ...
There are two main natural forces responsible for causing defects in timber and lumber: abnormal growth and rupture of tissues. Rupture of tissue includes cracks or splits in the wood called "shakes". "Ring shake", "wind shake", or "ring failure" is when the wood grain separates around the growth rings either while standing or during felling.
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 ...
A section of rosemary stem, an example of a woody plant, showing a typical wood structure. A woody plant is a plant that produces wood as its structural tissue and thus has a hard stem. [ 1 ] In cold climates, woody plants further survive winter or dry season above ground, as opposed to herbaceous plants that die back to the ground until spring .
Oak timber is a strong and hard wood with many uses, such as for furniture, floors, building frames, and veneers. [70] The wood of a red oak Quercus cerris (the Turkey oak) has better mechanical properties than those of the white oaks Q. petraea and Q. robur ; the heartwood and sapwood have similar mechanical properties . [ 71 ]
Glulam brace with plates used for connections Glulam frame of a roof structure. Glued laminated timber, commonly referred to as glulam, is a type of structural engineered wood product constituted by layers of dimensional lumber bonded together with durable, moisture-resistant structural adhesives so that all of the grain runs parallel to the longitudinal axis.