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Litmus is a water-soluble mixture of different dyes extracted from lichens. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. In an acidic medium, blue litmus paper turns red, while in a basic or alkaline medium, red litmus paper turns blue. In short, it is a dye and ...
Wood science [1] is the scientific field which predominantly studies and investigates elements associated with the formation, the physical and chemical composition, and the macro- and microstructure of wood as a bio-based and lignocellulosic material.
He named the substance "lignine", which is derived from the Latin word lignum, [4] meaning wood. It is one of the most abundant organic polymers on Earth , exceeded only by cellulose and chitin . Lignin constitutes 30% of terrestrial non- fossil organic carbon [ 5 ] on Earth, and 20 to 35% of the dry mass of wood.
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 term limnology was coined by François-Alphonse Forel (1841–1912) who established the field with his studies of Lake Geneva.Interest in the discipline rapidly expanded, and in 1922 August Thienemann (a German zoologist) and Einar Naumann (a Swedish botanist) co-founded the International Society of Limnology (SIL, from Societas Internationalis Limnologiae).
Lignum vitae is hard and durable, and is also the densest wood traded (average dried density: ~79 lb/ft 3 or ~1,260 kg/m 3); [4] it will easily sink in water. On the Janka scale of hardness, which measures hardness of woods, lignum vitae ranks highest of the trade woods, with a Janka hardness of 4,390 lbf (compared with Olneya at 3,260 lbf, [5] African blackwood at 2,940 lbf, hickory at 1,820 ...
Ep = epidermis; C = cortex; BF = bast fibres; P = phloem; X = xylem; Pi = pith Women in southern Norway weaving with linden bast fibres Ndimbu mask from Tanganyika, made with wood, hair and bast Bast fibre (also called phloem fibre or skin fibre ) is plant fibre collected from the phloem (the "inner bark", sometimes called "skin") or bast ...
There is also a reported link between the age of the wood and the spiral angle of the fibrils with respect to the longitudinal direction. Earlywood is said to have a consistent 4.6 ± 0.6° rest angle, whereas latewood is said to have a transition region from 4.6° to 19.8 ± 0.7°. [ 18 ]