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Ptaeroxylon Obliquum
''Ptaeroxylon obliquum'' is the botanical name for the sneezewood tree. It is native to Southern Africa, including South Africa, Zimbabwe, and Mozambique. It is the only species in the genus ''Ptaeroxylon''. Background ''Ptaeroxylon obliquum'' is a species from the family Rutaceae which are most abundant in South Africa and Australia. The term ''ptaeroxylon'' is Greek for sneeze and wood, while ''obliquum'' denotes the oblique shape of the leaflets. The wood produces oils containing nieshoutol, which causes violent sneeze attacks by workers who are exposed to the tree. Though sneezewood is not poisonous, it has been known to cause respiratory complications. It has been linked to asthma, rhinitis and mucosal inflammation. Description left, 200px, foliage left, 200px, male flowers ''Ptaeroxylon obliquum'' is a shrub or medium deciduous tree that stands up to tall. The bark is whitish-grey and smooth when young, but fissured with age. Leaflets are 2.5 x 1.3 cm marked a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thunb
Carl Peter Thunberg, also known as Karl Peter von Thunberg, Carl Pehr Thunberg, or Carl Per Thunberg (11 November 1743 – 8 August 1828), was a Swedish naturalist and an "apostle" of Carl Linnaeus. After studying under Linnaeus at Uppsala University, he spent seven years travelling in southern Africa and Asia, collecting and describing many plants and animals new to European science, and observing local cultures. He has been called "the father of South African botany", "pioneer of Occidental Medicine in Japan", and the "Japanese Linnaeus". Early life Thunberg was born and grew up in Jönköping, Sweden. At the age of 18, he entered Uppsala University where he was taught by Carl Linnaeus, regarded as the "father of modern taxonomy". Thunberg graduated in 1767 after 6 years of studying. To deepen his knowledge in botany, medicine and natural history, he was encouraged by Linnaeus in 1770 to travel to Paris and Amsterdam. In Amsterdam and Leiden Thunberg met the Dutch botanis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brass
Brass is an alloy of copper (Cu) and zinc (Zn), in proportions which can be varied to achieve different mechanical, electrical, and chemical properties. It is a substitutional alloy: atoms of the two constituents may replace each other within the same crystal structure. Brass is similar to bronze, another copper alloy, that uses tin instead of zinc. Both bronze and brass may include small proportions of a range of other elements including arsenic (As), lead (Pb), phosphorus (P), aluminium (Al), manganese (Mn), and silicon (Si). Historically, the distinction between the two alloys has been less consistent and clear, and modern practice in museums and archaeology increasingly avoids both terms for historical objects in favor of the more general "copper alloy". Brass has long been a popular material for decoration due to its bright, gold-like appearance; being used for drawer pulls and doorknobs. It has also been widely used to make utensils because of its low melting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xhosa People
The Xhosa people, or Xhosa language, Xhosa-speaking people (; ) are African people who are direct kinsmen of Tswana people, Sotho people and Twa people, yet are narrowly sub grouped by European as Nguni people, Nguni ethnic group whose traditional homeland is primarily the Cape Provinces, Cape Provinces of South Africa, however the skulls from Mapungubwe empire shows that they have always been in Southern Africa like their kinsmen and had developed a sophisticated culture as well as civilization. They were the second largest racial group in apartheid Southern Africa and are native speakers of the Xhosa language, IsiXhosa language. Presently, approximately eight million Xhosa speaking African people are distributed across the country, and the Xhosa language is South Africa's second-most-populous home language, after the Zulu, again we must qualify the former statement as in great countries like China, Xhosa and Zulu language would not be classified as different languages, rather ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telegraph Pole
A utility pole is a column or post typically made out of wood used to support overhead power lines and various other public utilities, such as electrical cable, fiber optic cable, and related equipment such as transformers and street lights. It can be referred to as a transmission pole, telephone pole, telecommunication pole, power pole, hydro pole, telegraph pole, or telegraph post, depending on its application. A Stobie pole is a multi-purpose pole made of two steel joists held apart by a slab of concrete in the middle, generally found in South Australia. Electrical wires and cables are routed overhead on utility poles as an inexpensive way to keep them insulated from the ground and out of the way of people and vehicles. Utility poles can be made of wood, metal, concrete, or composites like fiberglass. They are used for two different types of power lines: ''sub transmission lines'', which carry higher voltage power between substations, and ''distribution lines'', which distri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fence
A fence is a structure that encloses an area, typically outdoors, and is usually constructed from posts that are connected by boards, wire, rails or netting. A fence differs from a wall in not having a solid foundation along its whole length. Alternatives to fencing include a ditch (sometimes filled with water, forming a moat). Types By function * Agricultural fencing, to keep livestock in and/or predators out * Blast fence, a safety device that redirects the high energy exhaust from a jet engine * Sound barrier or acoustic fencing, to reduce noise pollution * Crowd control barrier * Privacy fencing, to provide privacy and security * Temporary fencing, to provide safety, security, and to direct movement; wherever temporary access control is required, especially on building and construction sites * Perimeter fencing, to prevent trespassing or theft and/or to keep children and pets from wandering away. * Decorative fencing, to enhance the appearance of a property, garden ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tugboat
A tugboat or tug is a marine vessel that manoeuvres other vessels by pushing or pulling them, with direct contact or a tow line. These boats typically tug ships in circumstances where they cannot or should not move under their own power, such as in crowded harbour or narrow canals, or cannot move at all, such as barges, disabled ships, log rafts, or oil platforms. Some are ocean-going, some are icebreakers or salvage tugs. Early models were powered by steam engines, long ago superseded by diesel engines. Many have deluge gun water jets, which help in firefighting, especially in harbours. Types Seagoing Seagoing tugs (deep-sea tugs or ocean tugboats) fall into four basic categories: #The standard seagoing tug with model bow that tows almost exclusively by way of a wire cable. In some rare cases, such as some USN fleet tugs, a synthetic rope hawser may be used for the tow in the belief that the line can be pulled aboard a disabled ship by the crew owing to its lightness ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steamboat
A steamboat is a boat that is marine propulsion, propelled primarily by marine steam engine, steam power, typically driving propellers or Paddle steamer, paddlewheels. Steamboats sometimes use the ship prefix, prefix designation SS, S.S. or S/S (for 'Screw Steamer') or PS (for 'Paddle Steamer'); however, these designations are most often used for steamships. The term ''steamboat'' is used to refer to smaller, insular, steam-powered boats working on lakes and rivers, particularly riverboats. As using steam became more reliable, steam power became applied to larger, ocean-going vessels. Background Limitations of the Newcomen steam engine Early steamboat designs used Newcomen atmospheric engine, Newcomen steam engines. These engines were large, heavy, and produced little power, which resulted in an unfavorable power-to-weight ratio. The Newcomen engine also produced a reciprocating or rocking motion because it was designed for pumping. The piston stroke was caused by a water jet i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuel
A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but has since also been applied to other sources of heat energy, such as nuclear energy (via nuclear fission and nuclear fusion). The heat energy released by reactions of fuels can be converted into mechanical energy via a heat engine. Other times, the heat itself is valued for warmth, cooking, or industrial processes, as well as the illumination that accompanies combustion. Fuels are also used in the cells of organisms in a process known as cellular respiration, where organic molecules are oxidized to release usable energy. Hydrocarbons and related organic molecules are by far the most common source of fuel used by humans, but other substances, including radioactive metals, are also utilized. Fuels are contrasted with other substances or de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Woodturning
Woodturning is the craft of using a wood lathe with hand-held tools to cut a shape that is symmetrical around the axis of rotation. Like the potter's wheel, the wood lathe is a simple mechanism that can generate a variety of forms. The operator is known as a turner, and the skills needed to use the tools were traditionally known as turnery. In pre-industrial England, these skills were sufficiently difficult to be known as 'the misterie' of the turners guild. The skills to use the tools by hand, without a fixed point of contact with the wood, distinguish woodturning and the wood lathe from the machinist's lathe, or metal-working lathe. Items made on the lathe include tool handles, candlesticks, egg cups, knobs, lamps, rolling pins, cylindrical boxes, Christmas ornaments, bodkins, knitting needles, needle cases, thimbles, pens, chessmen, spinning tops; legs, spindles, and pegs for furniture; balusters and newel A newel, also called a central pole or support column, is the cent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heartwood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose 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 it is defined 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 support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients between 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, or woodchips or fiber. 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] |
Xylophone
The xylophone (; ) is a musical instrument in the percussion family that consists of wooden bars struck by mallets. Like the glockenspiel (which uses metal bars), the xylophone essentially consists of a set of tuned wooden keys arranged in the fashion of the keyboard of a piano. Each bar is an idiophone tuned to a pitch of a musical scale, whether pentatonic or heptatonic in the case of many African and Asian instruments, diatonic in many western children's instruments, or chromatic for orchestral use. The term ''xylophone'' may be used generally, to include all such instruments such as the marimba, balafon and even the semantron. However, in the orchestra, the term ''xylophone'' refers specifically to a chromatic instrument of somewhat higher pitch range and drier timbre than the marimba, and these two instruments should not be confused. A person who plays the xylophone is known as a ''xylophonist'' or simply a ''xylophone player''. The term is also popularly used to refer to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Furniture
Furniture refers to movable objects intended to support various human activities such as seating (e.g., stools, chairs, and sofas), eating (tables), storing items, eating and/or working with an item, and sleeping (e.g., beds and hammocks). Furniture is also used to hold objects at a convenient height for work (as horizontal surfaces above the ground, such as tables and desks), or to store things (e.g., cupboards, shelves, and drawers). Furniture can be a product of design and can be considered a form of decorative art. In addition to furniture's functional role, it can serve a symbolic or religious purpose. It can be made from a vast multitude of materials, including metal, plastic, and wood. Furniture can be made using a variety of woodworking joints which often reflects the local culture. People have been using natural objects, such as tree stumps, rocks and moss, as furniture since the beginning of human civilization and continues today in some households/campsites. Ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
