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Blackett's Aerophor
:''Distinguish from aerophor (or aerophore) (a device to assist musicians playing wind instruments) and from aerophone.'' The Blackett's Aerophor is a nitrox semi-closed-circuit rebreather with liquid gas storage made in England from 1910 onwards for use in mine rescue and other industrial uses. It was used until the 1950s. "Aerophor" is from Greek language, Greek αεροφορος = "air-carrier". Its breathing bag was on the chest, of rubber, in a strong leather case. The other parts were in a backpack. It had two corrugated Breathing tube (breathing apparatus), breathing tubes coming out of the backpack. Its duration on a fill was 2 hours. It had: * A heat-insulated tank containing 5½ pounds of liquid nitrox containing at least 50% of oxygen, which had to be filled immediately before use. * At the bottom of the backpack, a large canister filled with 2 pounds of what one description called "potash" and another description "soda". Colonel Wiliam Cuthbert Blackett, who had previ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerophor
An aerophor (sometimes spelled aerophore, aerophon, or aerophone) is a device designed to provide an auxiliary breath supply to aid players of wind instruments in performing extended notes or passages. It was invented in 1912 by Bernard Samuels, a Dutch flautist in the Court Theatre of the Grand Duke of Grand Duchy of Mecklenburg-Schwerin, Mecklenburg-Schwerin.A Dictionary of Modern Music and Musicians. United Kingdom, J. M. Dent & sons, Limited, 1924, pg 7. Design The device consists of a small, foot-operated bellows that pumps air into the player's mouth via a rubber tube, which is fitted with a Check valve, one-way valve to prevent the air from the player's lungs from passing into the bellows. The aerophor Mouthpiece (woodwind), mo ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Instruments
A wind instrument is a musical instrument that contains some type of resonator (usually a tube) in which a column of air is set into vibration by the player blowing into (or over) a mouthpiece set at or near the end of the resonator. The pitch of the vibration is determined by the length of the tube and by manual modifications of the effective length of the vibrating column of air. In the case of some wind instruments, sound is produced by blowing through a reed; others require buzzing into a metal mouthpiece, while yet others require the player to blow into a hole at an edge, which splits the air column and creates the sound. Methods for obtaining different notes * Using different air columns for different tones, such as in the pan flute. These instruments can play several notes at once. * Changing the length of the vibrating air column by changing the length of the tube through engaging valves ''(see rotary valve, piston valve)'' which route the air through additional tubin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerophone
An aerophone is a musical instrument that produces sound primarily by causing a body of air to vibrate, without the use of strings or membranes (which are respectively chordophones and membranophones), and without the vibration of the instrument itself adding considerably to the sound (or idiophones). According to Curt Sachs: These may be lips, a mechanical reed, or a sharp edge. Also, an aerophone may be excited by percussive acts, such as the slapping of the keys of a flute or of any other woodwind. A free aerophone lacks the enclosed column of air yet, "cause a series of condensations and rarefications by various means." Overview Aerophones are one of the four main classes of instruments in the original Hornbostel–Sachs system of musical instrument classification, which further classifies aerophones by whether or not the vibrating air is contained within the instrument. The first class (41) includes instruments which, when played, do ''not'' contain the vibrating air. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rebreather
A rebreather is a breathing apparatus that absorbs the carbon dioxide of a user's exhaled breath to permit the rebreathing (recycling) of the substantial unused oxygen content, and unused inert content when present, of each breath. Oxygen is added to replenish the amount metabolised by the user. This differs from open-circuit breathing apparatus, where the exhaled gas is discharged directly into the environment. The purpose is to extend the breathing endurance of a limited gas supply, while also eliminating the bubbles otherwise produced by an open circuit system. The latter advantage over other systems is useful for covert military operations by frogmen, as well as for undisturbed observation of underwater wildlife. A rebreather is generally understood to be a portable apparatus carried by the user. The same technology on a vehicle or non-mobile installation is more likely to be referred to as a life-support system. Rebreather technology may be used where breathing gas supp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mine Rescue
Mine rescue or mines rescue is the specialised job of rescuing miners and others who have become trapped or injured in underground mines because of mining accidents, roof falls or floods and disasters such as explosions. Background Mining laws in developed countries require trained, equipped mine rescue personnel to be available at all mining operations at surface and underground mining operations. Mine rescue teams must know the procedures used to rescue miners trapped by various hazards, including fire, explosions, cave-ins, toxic gas, smoke inhalation, and water entering the mine. Most mine rescue teams are composed of miners who know the mine and are familiar with the mining machinery they may encounter during the rescue, the layout of workings and geological conditions and working practices. Local and state governments may have teams on-call ready to respond to mine accidents. Rescuers and equipment The first mines rescuers were the colliery managers and volunteer c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Language
Greek (, ; , ) is an Indo-European languages, Indo-European language, constituting an independent Hellenic languages, Hellenic branch within the Indo-European language family. It is native to Greece, Cyprus, Italy (in Calabria and Salento), southern Albania, and other regions of the Balkans, Caucasus, the Black Sea coast, Asia Minor, and the Eastern Mediterranean. It has the list of languages by first written accounts, longest documented history of any Indo-European language, spanning at least 3,400 years of written records. Its writing system is the Greek alphabet, which has been used for approximately 2,800 years; previously, Greek was recorded in writing systems such as Linear B and the Cypriot syllabary. The Greek language holds a very important place in the history of the Western world. Beginning with the epics of Homer, ancient Greek literature includes many works of lasting importance in the European canon. Greek is also the language in which many of the foundational texts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breathing Tube (breathing Apparatus)
A rebreather is a breathing apparatus that absorbs the carbon dioxide of a user's exhaled breath to permit the rebreathing (recycling) of the substantial unused oxygen content, and unused inert content when present, of each breath. Oxygen is added to replenish the amount metabolised by the user. This differs from open-circuit breathing apparatus, where the exhaled gas is discharged directly into the environment. The purpose is to extend the breathing endurance of a limited gas supply, while also eliminating the bubbles otherwise produced by an open circuit system. The latter advantage over other systems is useful for covert military operations by frogmen, as well as for undisturbed observation of underwater wildlife. A rebreather is generally understood to be a portable apparatus carried by the user. The same technology on a vehicle or non-mobile installation is more likely to be referred to as a life-support system. Rebreather technology may be used where breathing gas supply i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Backpack
A backpack, also called knapsack, schoolbag, rucksack, pack, booksack, bookbag, haversack, packsack, or backsack, is in its simplest frameless form, a fabric sack carried on one's back and secured with two straps that go over the shoulders; but it can have an external or internal frame, and there are bodypacks. Backpacks are commonly used by hikers and students, and are often preferred to handbags for carrying heavy loads or carrying any sort of equipment, because of the limited capacity to carry heavy weights for long periods of time with hands. Large backpacks, used to carry loads over , as well as smaller sports backpacks (e.g. running, cycling, hiking, and hydration), usually offload the largest part (up to about 90%) of their weight onto padded hip belts, leaving the shoulder straps mainly for stabilizing the load. This improves the potential to carry heavy loads, as the hips are stronger than the shoulders, and also increases agility and balance, since the load rides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrox
Nitrox refers to any gas mixture composed (excepting trace gases) of nitrogen and oxygen. It is usually used for mixtures that contain less than 78% nitrogen by volume. In the usual application, underwater diving, nitrox is normally distinguished from air and handled differently. The most common use of nitrox mixtures containing oxygen in higher proportions than atmospheric air is in scuba diving, where the reduced partial pressure of nitrogen is advantageous in reducing nitrogen uptake in the body's tissues, thereby extending the practicable underwater dive time by reducing the decompression requirement, or reducing the risk of decompression sickness (also known as ''the bends''). The two most common recreational diving nitrox mixes are 32% and 36% oxygen, which have maximum operating depths of about 110 feet (34 meters) and 95 feet (29 meters) respectively. Nitrox is used to a lesser extent in surface-supplied diving, as these advantages are reduced by the more complex logi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other chemical compound, compounds. Oxygen is abundance of elements in Earth's crust, the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides and silicates.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. It is abundance of chemical elements, the third-most abundant element in the universe after hydrogen and helium. At standard temperature and pressure, two oxygen atoms will chemical bond, bind covalent bond, covalently to form dioxygen, a colorless and odorless diatomic gas with the chemical formula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Durham, England
Durham ( , locally ) is a cathedral city and civil parish in the county of County Durham, Durham, England. It is the county town and contains the headquarters of Durham County Council, the unitary authority which governs the district of County Durham (district), County Durham. The built-up area had a population of 50,510 at the 2021 Census. The city was built on a meander of the River Wear, which surrounds the centre on three sides and creates a narrow neck on the fourth. The surrounding land is hilly, except along the Wear's floodplain to the north and southeast. Durham was founded in 995 by Anglo-Saxon monks seeking a place safe from Viking Age, Viking raids to house the relics of St Cuthbert. The church the monks built lasted only a century, as it was replaced by the present Durham Cathedral after the Norman Conquest; together with Durham Castle it is a UNESCO World Heritage Site. From the 1070s until 1836 the city was part of the County Palatine of Durham, a semi-independ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
