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Bottled Oxygen (mountaineering)
High altitude breathing apparatus is breathing apparatus which allows a person to breathe more effectively at an altitude where the partial pressure of oxygen in the ambient atmospheric air is insufficient for the task or to sustain consciousness or human life over the long or short term. High altitude breathing sets may be classified by type in several ways: * by application: aviation breathing apparatus and mountaineering breathing apparatus. * by breathing gas source: self-contained gas supply, or remotely supplied gas, * by breathing circuit type: open, semi-closed, or closed circuit, * by gas supply type: constant flow, supply on demand, or supplemental, * by ventilatory driving force: the breathing effort of the user, or mechanical work from an external source, * by gas mixture: air, oxygen enriched, or pure oxygen. The user respiratory interface is the delivery system by which the breathing apparatus guides the breathing gas flow to and from the user. Some form of fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edmund Hillary And Tenzing Norgay
Edmund is a masculine given name or surname in the English language. The name is derived from the Old English elements ''ēad'', meaning "prosperity" or "riches", and ''mund'', meaning "protector". Persons named Edmund include: People Kings and nobles *Edmund the Martyr (died 869 or 870), king of East Anglia *Edmund I (922–946), King of England from 939 to 946 * Edmund Ironside (989–1016), also known as Edmund II, King of England in 1016 * Edmund of Scotland (after 1070 – after 1097) * Edmund Crouchback (1245–1296), son of King Henry III of England and claimant to the Sicilian throne *Edmund, 2nd Earl of Cornwall (1249–1300), earl of Cornwall; English nobleman of royal descent *Edmund of Langley, 1st Duke of York (1341–1402), son of King Edward III of England * Edmund Tudor, earl of Richmond (1430–1456), English and Welsh nobleman *Edmund, Prince of Schwarzenberg (1803–1873), the last created Austrian field marshal of the 19th century In religion * Saint Edmund ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dysbarism
Dysbarism refers to medical conditions resulting from changes in ambient pressure. Various activities are associated with pressure changes. Underwater diving is the most frequently cited example, but pressure changes also affect people who work in other pressurized environments (for example, caisson workers), and people who move between different altitudes. Ambient pressure Ambient pressure is the pressure in the water around the diver (or the air, with caisson workers etc.). As a diver descends, the ambient pressure increases. At in salt water, it is twice the normal pressure than that at the surface. At 40 meters (a common recommended limit for recreational diving) it is 5 times the pressure than at sea level. Pressure decreases as we rise above sea level, but less dramatically. At 3000 feet altitude Altitude or height (also sometimes known as depth) is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane Gas Separation
Gas mixtures can be effectively separated by synthetic membranes made from polymers such as polyamide or cellulose acetate, or from ceramic materials. While polymeric membranes are economical and technologically useful, they are bounded by their performance, known as the Robeson limit (permeability must be sacrificed for selectivity and vice versa). This limit affects polymeric membrane use for CO2 separation from flue gas streams, since mass transport becomes limiting and CO2 separation becomes very expensive due to low permeabilities. Membrane materials have expanded into the realm of silica, zeolites, metal-organic frameworks, and perovskites due to their strong thermal and chemical resistance as well as high tunability (ability to be modified and functionalized), leading to increased permeability and selectivity. Membranes can be used for separating gas mixtures where they act as a permeable barrier through which different compounds move across at different rates or not move ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure Swing Adsorption
Pressure swing adsorption (PSA) is a technique used to separate some gas species from a mixture of gases (typically air) under pressure according to the species' molecular characteristics and affinity for an adsorbent material. It operates at near-ambient temperature and significantly differs from the cryogenic distillation commonly used to separate gases. Selective adsorbent materials (e.g., zeolites, (aka molecular sieves), activated carbon, etc.) are used as trapping material, preferentially adsorbing the target gas species at high pressure. The process then swings to low pressure to desorb the adsorbed gas. Process Pressure swing adsorption process (PSA) is based on the phenomenon that under high pressure, gases tend to be trapped onto solid surfaces, ''i.e.'', to be "adsorbed". The higher the pressure, the more gas is adsorbed. When the pressure is dropped, the gas is released, or desorbed. PSA can be used to separate gases in a mixture because different gases are adsorbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen Therapy
Oxygen therapy, also known as supplemental oxygen, is the use of oxygen as medical treatment. Acute indications for therapy include hypoxemia (low blood oxygen levels), carbon monoxide toxicity and cluster headache. It may also be prophylactically given to maintain blood oxygen levels during the induction of anesthesia. Oxygen therapy is often useful in chronic hypoxemia caused by conditions such as severe COPD or cystic fibrosis. Oxygen can be delivered via nasal cannula or face mask, or via high pressure conditions such as in endotracheal intubation or hyperbaric chamber. It can also be given through bypassing the airway, such as in ECMO therapy. Oxygen is required for normal cellular metabolism. However, excessively high concentrations can result in oxygen toxicity, leading to lung damage and respiratory failure. Higher oxygen concentrations can also increase the risk of airway fires, particularly while smoking. Oxygen therapy can also dry out the nasal mucosa without humidi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Device
A medical device is any device intended to be used for medical purposes. Significant potential for hazards are inherent when using a device for medical purposes and thus medical devices must be proved safe and effective with reasonable assurance before regulating governments allow marketing of the device in their country. As a general rule, as the associated risk of the device increases the amount of testing required to establish safety and efficacy also increases. Further, as associated risk increases the potential benefit to the patient must also increase. Discovery of what would be considered a medical device by modern standards dates as far back as c. 7000 BC in Baluchistan where Neolithic dentists used flint-tipped drills and bowstrings. Study of archeology and Roman medical literature also indicate that many types of medical devices were in widespread use during the time of ancient Rome. In the United States it wasn't until the Federal Food, Drug, and Cosmetic Act (F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Dioxide Scrubbing Reaction
A carbon dioxide scrubber is a piece of equipment that absorbs carbon dioxide (CO2). It is used to treat exhaust gases from industrial plants or from exhaled air in life support systems such as rebreathers or in spacecraft, submersible craft or airtight chambers. Carbon dioxide scrubbers are also used in controlled atmosphere (CA) storage. They have also been researched for carbon capture and storage as a means of combating climate change. Technologies Amine scrubbing The primary application for CO2 scrubbing is for removal of CO2 from the exhaust of coal- and gas-fired power plants. Virtually the only technology being seriously evaluated involves the use of various amines, e.g. monoethanolamine. Cold solutions of these organic compounds bind CO2, but the binding is reversed at higher temperatures: :CO2 + 2 ↔ + , this technology has only been lightly implemented because of capital costs of installing the facility and the operating costs of utilizing it. Minerals an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulmonary Oxygen Toxicity
Oxygen toxicity is a condition resulting from the harmful effects of breathing molecular oxygen () at increased partial pressures. Severe cases can result in cell damage and death, with effects most often seen in the central nervous system, lungs, and eyes. Historically, the central nervous system condition was called the Paul Bert effect, and the pulmonary condition the Lorrain Smith effect, after the researchers who pioneered the discoveries and descriptions in the late 19th century. Oxygen toxicity is a concern for underwater divers, those on high concentrations of supplemental oxygen (particularly premature babies), and those undergoing hyperbaric oxygen therapy. The result of breathing increased partial pressures of oxygen is hyperoxia, an excess of oxygen in body tissues. The body is affected in different ways depending on the type of exposure. Central nervous system toxicity is caused by short exposure to high partial pressures of oxygen at greater than atmospheric pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Altitude Parachuting
High-altitude military parachuting, or military free fall (MFF), is a method of delivering military personnel, military equipment, and other military supplies from a transport aircraft at a high altitude via free-fall parachute insertion. Two techniques are used: HALO (high altitude – low opening, often called a HALO jump) and HAHO (high altitude – high opening). In the HALO technique, the parachutist opens the parachute at a low altitude after free-falling for a period of time, while in the HAHO technique, the parachutist opens the parachute at a high altitude just a few seconds after jumping from the aircraft. Although HALO techniques were first developed in the 1960s for military use, in recent years HALO parachute designs have been more widely used in non-military applications, including as a form of skydiving. In military operations, HALO is also used for delivering equipment, supplies, or personnel, while HAHO is generally used exclusively for personn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountaineering Breathing Apparatus
High altitude breathing apparatus is breathing apparatus which allows a person to breathe more effectively at an altitude where the partial pressure of oxygen in the ambient atmospheric air is insufficient for the task or to sustain consciousness or human life over the long or short term. High altitude breathing sets may be classified by type in several ways: * by application: aviation breathing apparatus and mountaineering breathing apparatus. * by breathing gas source: self-contained gas supply, or remotely supplied gas, * by breathing circuit type: open, semi-closed, or closed circuit, * by gas supply type: constant flow, supply on demand, or supplemental, * by ventilatory driving force: the breathing effort of the user, or mechanical work from an external source, * by gas mixture: air, oxygen enriched, or pure oxygen. The user respiratory interface is the delivery system by which the breathing apparatus guides the breathing gas flow to and from the user. Some form of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respiratory Minute Volume
Minute ventilation (or respiratory minute volume or minute volume) is the volume of gas inhaled (inhaled minute volume) or exhaled (exhaled minute volume) from a person's lungs per minute. It is an important parameter in respiratory medicine due to its relationship with blood carbon dioxide levels. It can be measured with devices such as a Wright respirometer or can be calculated from other known respiratory parameters. Although minute volume can be viewed as a unit of volume, it is usually treated in practice as a flow rate (given that it represents a volume change over time). Typical units involved are (in metric) 0.5 L × 12 breaths/min = 6 L/min. Several symbols can be used to represent minute volume. They include \dot (V̇ or V-dot) or Q (which are general symbols for flow rate), MV, and VE. Determination of minute volume Minute volume can either be measured directly or calculated from other known parameters. Measurement of minute volume Minute volume is the amount ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Death Zone
In mountaineering, the death zone refers to altitudes above a certain point where the pressure of oxygen is Effects of high altitude on humans, insufficient to sustain human life for an extended time span. This point is generally tagged as , less than 356 millibars of atmospheric pressure). The concept was conceived in 1953 by Edouard Wyss-Dunant, a Swiss doctor, who called it the lethal zone. All eight-thousander, 14 peaks above 8000 m in the death zone are located in the Himalaya and Karakoram of Asia. Many deaths in high-altitude mountaineering have been caused by the effects of the death zone, either directly by loss of vital functions or indirectly by wrong decisions made under stress, or physical weakening leading to accidents. An extended stay above without Bottled oxygen (climbing), supplementary oxygen will result in deterioration of bodily functions and death. Physiological background The human body has optimal endurance below elevation. The Atmospheric chemistry, c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
