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Hardwoods
Hardwood is wood from angiosperm trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen. Hardwood (which comes from angiosperm trees) contrasts with softwood (which is from gymnosperm trees). Characteristics Hardwoods are produced by angiosperm trees that reproduce by flowers, and have broad leaves. Many species are deciduous. Those of temperate regions lose their leaves every autumn as temperatures fall and are dormant in the winter, but those of tropical regions may shed their leaves in response to seasonal or sporadic periods of drought. Hardwood from deciduous species, such as oak, normally shows annual growth rings, but these may be absent in some tropical hardwoods. Hardwoods have a more complex structure than softwoods and are often much slower growing as a result. The dominant feature separating "hardwoods" from softwoods is the presen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fagus Wood
Beech (genus ''Fagus'') is a genus of deciduous trees in the family Fagaceae, native to subtropical (accessory forest element) and temperate (as dominant element of mesophytic forests) Eurasia and North America. There are 14 accepted species in two distinct subgenera, ''Englerianae'' and ''Fagus''. The subgenus ''Englerianae'' is found only in East Asia, distinctive for its low branches, often made up of several major trunks with yellowish bark. The better known species of subgenus ''Fagus'' are native to Europe, western and eastern Asia and eastern North America. They are high-branching trees with tall, stout trunks and smooth silver-grey bark. The European beech ''Fagus sylvatica'' is the most commonly cultivated species, yielding a utility timber used for furniture construction, flooring and engineering purposes, in plywood, and household items. The timber can be used to build homes. Beechwood makes excellent firewood. Slats of washed beech wood are spread around the bottom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropical Timber
Tropical timber may refer to any type of timber or wood that grows in tropical rainforests and tropical and subtropical moist broadleaf forests and is harvested there. Typical examples of worldwide industrial significance include, among others, the following hardwoods: * Chloroxylon * Ebony * Mahogany * Narra * Rosewood * Teak Overexploitation of those woods has led to widespread deforestation in the tropics. The intergovernmental organization International Tropical Timber Organization is concerned with conservation of the habitats of tropical timber trees. See also * CITES * Forest Stewardship Council * Forestry * International Tropical Timber Agreement, 2006 * Plant Resources of Tropical Africa * Tropical forest Tropical forests are forested ecoregions with tropical climates – that is, land areas approximately bounded by the Tropic of Cancer, tropics of Cancer and Tropic of Capricorn, Capricorn, but possibly affected by other factors such as prevailing ... * Tropi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatty Acid
In chemistry, in particular in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated and unsaturated compounds#Organic chemistry, saturated or unsaturated. Most naturally occurring fatty acids have an Branched chain fatty acids, unbranched chain of an even number of carbon atoms, from 4 to 28. Fatty acids are a major component of the lipids (up to 70% by weight) in some species such as microalgae but in some other organisms are not found in their standalone form, but instead exist as three main classes of esters: triglycerides, phospholipids, and cholesteryl esters. In any of these forms, fatty acids are both important diet (nutrition), dietary sources of fuel for animals and important structural components for cell (biology), cells. History The concept of fatty acid (''acide gras'') was introduced in 1813 by Michel Eugène Chevreul, though he initially used some variant terms: ''graisse acide'' and ''acide huileux'' ("acid fat" and "oi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenols
In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (− O H) bonded directly to an aromatic hydrocarbon group. The simplest is phenol, . Phenolic compounds are classified as simple phenols or polyphenols based on the number of phenol units in the molecule. Phenols are both synthesized industrially and produced by plants and microorganisms. Properties Acidity Phenols are more acidic than typical alcohols. The acidity of the hydroxyl group in phenols is commonly intermediate between that of aliphatic alcohols and carboxylic acids (their pKa is usually between 10 and 12). Deprotonation of a phenol forms a corresponding negative phenolate ion or phenoxide ion, and the corresponding salts are called phenolates or phenoxides (aryloxides, according to the IUPAC Gold Book). Condensation with aldehydes and ketones Phenols are susceptible to electrophilic aromatic substitutions. Condensation with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terpene
Terpenes () are a class of natural products consisting of compounds with the formula (C5H8)n for n ≥ 2. Terpenes are major biosynthetic building blocks. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly Pinophyta, conifers. In plants, terpenes and terpenoids are important mediators of ecological biological interaction, interactions, while some insects use some terpenes as a form of defense. Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control. Terpenes are classified by the number of carbons: monoterpenes (C10), sesquiterpenes (C15), diterpenes (C20), as examples. The terpene alpha-pinene is a major component of the common solvent, turpentine. The one terpene that has major applications is natural rubber (i.e., polyisoprene). The possibility that other terpenes could be used as precursors to pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aliphatic Compound
In organic chemistry, hydrocarbons ( compounds composed solely of carbon and hydrogen) are divided into two classes: aromatic compounds and aliphatic compounds (; G. ''aleiphar'', fat, oil). Aliphatic compounds can be saturated (in which all the C-C bonds are single, requiring the structure to be completed, or 'saturated', by hydrogen) like hexane, or unsaturated, like hexene and hexyne. Open-chain compounds, whether straight or branched, and which contain no rings of any type, are always aliphatic. Cyclic compounds can be aliphatic if they are not aromatic. Structure Aliphatics compounds can be saturated, joined by single bonds ( alkanes), or unsaturated, with double bonds ( alkenes) or triple bonds ( alkynes). If other elements ( heteroatoms) are bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine, it is no longer a hydrocarbon, and therefore no longer an aliphatic compound. However, such compounds may still be referred to as al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or more broadly to include the same type of tissue elsewhere, such as in the roots of trees or shrubs. In a living tree, it performs a mechanical-support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients among the leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, woodchips, or fibers. Wood has been used for thousands of years for fuel, as a construction material, for making tools and weapons, furniture and paper. More recently it emerged as a feedstock for the production ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coniferyl Alcohol
Coniferyl alcohol is an organic compound with the formula HO(CH3O)C6H3CH=CHCH2OH. A colourless or white solid, it is one of the monolignols, produced via the phenylpropanoid biochemical pathway. When copolymerized with related aromatic compounds, coniferyl alcohol forms lignin or lignans. Coniferin is a glucoside of coniferyl alcohol. Coniferyl alcohol is an intermediate in biosynthesis of eugenol and of stilbenoids and coumarin. Gum benzoin contains significant amount of coniferyl alcohol and its esters. It is found in both gymnosperm and angiosperm plants. Sinapyl alcohol and paracoumaryl alcohol, the other two lignin monomers, are found in angiosperm plants and grasses. Occurrence Coniferyl alcohol is produced from coniferyl aldehyde by the action of dehydrogenase enzymes. It is a queen retinue pheromone (QRP), a type of honey bee pheromone found in the mandibular glands. In '' Forsythia intermedia'' a dirigent protein was found to direct the stereoselective b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinapyl Alcohol
Sinapyl alcohol is an organic compound structurally related to cinnamic acid. It is biosynthetized via the phenylpropanoid biochemical pathway, its immediate precursor being sinapaldehyde. This phytochemical is one of the monolignols, which are precursor to lignin or lignans. It is also a biosynthetic precursor to various stilbenoids and coumarins. See also * Sinapinic acid *Syringol *Syringaldehyde *Syringic acid * Acetosyringone * Sinapine * Canolol *Phenolic content in wine Phenolic compounds— natural phenol and polyphenols—occur naturally in wine. These include a large group of several hundred chemical compounds that affect the taste, color and mouthfeel of wine. These compounds include phenolic acids, stilb ... References {{DEFAULTSORT:Sinapyl Alcohol Monolignols Ethers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lignin
Lignin is a class of complex organic polymers that form key structural materials in the support tissues of most plants. Lignins are particularly important in the formation of cell walls, especially in wood and bark, because they lend rigidity and do not rot easily. Chemically, lignins are polymers made by cross-linking phenolic precursors. History Lignin was first mentioned in 1813 by the Swiss botanist A. P. de Candolle, who described it as a fibrous, tasteless material, insoluble in water and alcohol but soluble in weak alkaline solutions, and which can be precipitated from solution using acid. He named the substance "lignine", which is derived from the Latin word '' lignum'', 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 on Earth, and 20 to 35% of the dry mass of wood. Lignin is present in red algae, which suggest that the common ancestor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemicellulose
A hemicellulose (also known as polyose) is one of a number of heteropolymers (matrix polysaccharides), such as arabinoxylans, present along with cellulose in almost all embryophyte, terrestrial plant cell walls. Cellulose is crystalline, strong, and resistant to hydrolysis. Hemicelluloses are branched, shorter in length than cellulose, and also show a propensity to crystallize. They can be hydrolyzed by dilute acid or Base (chemistry), base as well as a myriad of Cellulase, hemicellulase enzymes. Composition Diverse kinds of hemicelluloses are known. Important examples include xylan, glucuronoxylan, arabinoxylan, glucomannan, and xyloglucan. Hemicelluloses are polysaccharides often associated with cellulose, but with distinct compositions and structures. Whereas cellulose is derived exclusively from glucose, hemicelluloses are composed of diverse sugars, and can include the five-carbon sugars xylose and arabinose, the six-carbon sugars glucose, mannose and galactose, and the si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellulose
Cellulose is an organic compound with the chemical formula, formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of glycosidic bond, β(1→4) linked glucose, D-glucose units. Cellulose is an important structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. Some species of bacteria secrete it to form biofilms. Cellulose is the most abundant biopolymer, organic polymer on Earth. The cellulose content of cotton fibre is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%. Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon. Conversion of cellulose from energy crops into biofuels such as cellulosic ethanol is under development as a renewable fuel source. Cellulose for industrial use is mainly obtained from wood pulp and cotton. Cellulose is also greatly affected by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
