Wood is an organic material, a natural composite Composite materials are engineered materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct on a macroscopic level within the finished structure of cellulose Cellulose is an organic compound with the formula n, a polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1→4) linked D-glucose units fibers (which are strong in tension) embedded in a matrix of lignin Lignin or lignen is a complex chemical compound most commonly derived from wood, and an integral part of the secondary cell walls of plants and some algae. The term was introduced in 1819 by de Candolle and is derived from the Latin word lignum, meaning wood. It is one of the most abundant organic polymers on Earth, exceeded only by cellulose, which resists compression. In the strict sense wood is produced as secondary xylem In vascular plants, xylem is one of the two types of transport tissue, phloem being the other. The word "xylem" is derived from classical Greek ξυλον , "wood", and indeed the best-known xylem tissue is wood, though it is found throughout the plant. Its basic function is to transport water but it also transports some in the stems of trees A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to 6 m; some authors set a minimum of 10 cm trunk diameter (and other woody plants). In a living tree it transfers water Water is a ubiquitous chemical substance that is composed of hydrogen and oxygen and is vital for all known forms of life and nutrients A nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment. Nutrients are the substances that enrich the body. They build and repair tissues, give heat and energy, and regulate body processes. Methods for nutrient intake vary, with animals and to the leaves In botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin. There is continued debate about whether the flatness of leaves evolved to expose the chloroplasts to more light or to increase the absorption of carbon dioxide. In either case, the adaption was made at the expense and other growing tissues, and has a support function, enabling woody plants to reach large sizes or to stand up for themselves. However, wood may also refer to other plant materials with comparable properties, and to material engineered from wood, or wood chips or fiber.
People have used wood for millennia for many purposes, primarily as a fuel Fuel is any material that is burned or altered to obtain energy and to heat or to move objects. Fuel releases its energy either through a chemical reaction means, such as combustion, or nuclear means, such as nuclear fission or nuclear fusion. An important property of a useful fuel is that its energy can be stored to be released only when needed, or as a construction In the fields of architecture and civil engineering, construction is a process that consists of the building or assembling of infrastructure. Far from being a single activity, large scale construction is a feat of multitasking. Normally the job is managed by the project manager and supervised by the construction manager, design engineer, material for making houses A house is generally a home, shelter, building or structure that is a dwelling or place for habitation by human beings. The term includes many kinds of dwellings ranging from rudimentary huts of nomadic tribes to high-rise apartment buildings. In some contexts, "house" may mean the same as dwelling, residence, home, abode, lodging,, tools A tool, broadly defined, is an entity that interfaces between two or more domains; that facilitates more effective action of one domain upon the other. Basic tools are simple machines. For example, a crowbar simply functions as a lever. The further out from the pivot point, the more force is transmitted along the lever. A hammer typically, weapons A weapon is a tool used to apply force for the purpose of causing harm or damage to persons, animals or structures. Weapons are used in hunting, attack, self-defense, or defense in combat and range from simple, prehistoric weapons like clubs and spears to complicated modern weapons such as intercontinental ballistic missiles, furniture Furniture is the mass noun for the movable objects ('mobile' in Latin languages) intended to support various human activities such as seating and sleeping in beds, to hold objects at a convenient height for work using horizontal surfaces above the ground, or to store things. Storage furniture such as a nightstand often makes use of doors, drawers,, packaging, artworks, and paper Paper is a thin material mainly used for writing upon, printing upon or for packaging. It is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets. Wood can be dated by carbon dating Radiocarbon dating, or carbon dating, is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to determine the age of carbonaceous materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" (BP), "Present" and in some species by dendrochronology Dendrochronology or tree-ring dating is the scientific method of dating based on the analysis of patterns of tree-rings. Dendrochronology can date the time at which tree rings were formed, in many types of wood, to the exact calendar year. This has three main areas of application: paleoecology, where it is used to determine certain aspects of past to make inferences about when a wooden object was created. The year-to-year variation in tree-ring widths and isotopic abundances gives clues Climate proxies are devices that suggest the climate patterns of the past, even before those patterns were archived by humans. To produce the most precise results, systematic cross-verification between proxy indicators is necessary for accuracy in readings and record-keeping. The study of past climates is known as paleoclimatology. Examples of to the prevailing climate at that time.[1]
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Peterborough Examiner
The Wood family -- father John, mother Sandy, son Scott and daughter Grace, who has severe disabilities -- recently had full benefits restored for ...
