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24,000 | Current research evaluated whether Nivolumab can be used for the treatment of a Hodgkin's lymphoma. The evidence is very uncertain about the effect of Nivolumab for patients with a Hodgkin's lymphoma on the overall survival, the quality of life, the survival without a progression, the response rate (=complete disappear... | https://en.wikipedia.org/wiki?curid=71422 |
24,001 | Palliative care, a specialized medical care focused on the symptoms, pain, and stress of a serious illness, is recommended by multiple national cancer treatment guidelines as an accompaniment to curative treatments for people with lymphoma. It is used to address both the direct symptoms of lymphoma and many unwanted si... | https://en.wikipedia.org/wiki?curid=71422 |
24,002 | Adding physical exercises to the standard treatment for adult patients with haematological malignancies like lymphomas may result in little to no difference in the mortality, the quality of life and the physical functioning. These exercises may result in a slight reduction in depression. Furthermore, aerobic physical e... | https://en.wikipedia.org/wiki?curid=71422 |
24,003 | Lymphoma is the most common form of hematological malignancy, or "blood cancer", in the developed world. | https://en.wikipedia.org/wiki?curid=71422 |
24,004 | Taken together, lymphomas represent 5.3% of all cancers (excluding simple basal cell and squamous cell skin cancers) in the United States and 55.6% of all blood cancers. | https://en.wikipedia.org/wiki?curid=71422 |
24,005 | According to the U.S. National Institutes of Health, lymphomas account for about 5%, and Hodgkin lymphoma in particular accounts for less than 1% of all cases of cancer in the United States. | https://en.wikipedia.org/wiki?curid=71422 |
24,006 | Because the whole lymphatic system is part of the body's immune system, people with a weakened immune system such as from HIV infection or from certain drugs or medication also have a higher number of cases of lymphoma. | https://en.wikipedia.org/wiki?curid=71422 |
24,007 | Thomas Hodgkin published the first description of lymphoma in 1832, specifically of the form named after him. Since then, many other forms of lymphoma have been described. | https://en.wikipedia.org/wiki?curid=71422 |
24,008 | The two types of lymphoma research are clinical or translational research and basic research. Clinical/translational research focuses on studying the disease in a defined and generally immediately applicable way, such as testing a new drug in people. Studies may focus on effective means of treatment, better ways of tre... | https://en.wikipedia.org/wiki?curid=71422 |
24,009 | Basic science research studies the disease process at a distance, such as seeing whether a suspected carcinogen can cause healthy cells to turn into lymphoma cells in the laboratory or how the DNA changes inside lymphoma cells as the disease progresses. The results from basic research studies are generally less immedia... | https://en.wikipedia.org/wiki?curid=71422 |
24,010 | Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen ... | https://en.wikipedia.org/wiki?curid=22303 |
24,011 | Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and fats, as do the major constituent inorganic compounds of animal shells, teeth, and bone. Most of the mass of living organisms is oxygen as a component of water, the major constituent of ... | https://en.wikipedia.org/wiki?curid=22303 |
24,012 | Oxygen was isolated by Michael Sendivogius before 1604, but it is commonly believed that the element was discovered independently by Carl Wilhelm Scheele, in Uppsala, in 1773 or earlier, and Joseph Priestley in Wiltshire, in 1774. Priority is often given for Priestley because his work was published first. Priestley, ho... | https://en.wikipedia.org/wiki?curid=22303 |
24,013 | Common uses of oxygen include production of steel, plastics and textiles, brazing, welding and cutting of steels and other metals, rocket propellant, oxygen therapy, and life support systems in aircraft, submarines, spaceflight and diving. | https://en.wikipedia.org/wiki?curid=22303 |
24,014 | One of the first known experiments on the relationship between combustion and air was conducted by the 2nd century BCE Greek writer on mechanics, Philo of Byzantium. In his work "Pneumatica", Philo observed that inverting a vessel over a burning candle and surrounding the vessel's neck with water resulted in some water... | https://en.wikipedia.org/wiki?curid=22303 |
24,015 | In the late 17th century, Robert Boyle proved that air is necessary for combustion. English chemist John Mayow (1641–1679) refined this work by showing that fire requires only a part of air that he called "spiritus nitroaereus". In one experiment, he found that placing either a mouse or a lit candle in a closed contain... | https://en.wikipedia.org/wiki?curid=22303 |
24,016 | Mayow observed that antimony increased in weight when heated, and inferred that the nitroaereus must have combined with it. He also thought that the lungs separate nitroaereus from air and pass it into the blood and that animal heat and muscle movement result from the reaction of nitroaereus with certain substances in ... | https://en.wikipedia.org/wiki?curid=22303 |
24,017 | Robert Hooke, Ole Borch, Mikhail Lomonosov, and Pierre Bayen all produced oxygen in experiments in the 17th and the 18th century but none of them recognized it as a chemical element. This may have been in part due to the prevalence of the philosophy of combustion and corrosion called the "phlogiston theory", which was ... | https://en.wikipedia.org/wiki?curid=22303 |
24,018 | Established in 1667 by the German alchemist J. J. Becher, and modified by the chemist Georg Ernst Stahl by 1731, phlogiston theory stated that all combustible materials were made of two parts. One part, called phlogiston, was given off when the substance containing it was burned, while the dephlogisticated part was tho... | https://en.wikipedia.org/wiki?curid=22303 |
24,019 | Highly combustible materials that leave little residue, such as wood or coal, were thought to be made mostly of phlogiston; non-combustible substances that corrode, such as iron, contained very little. Air did not play a role in phlogiston theory, nor were any initial quantitative experiments conducted to test the idea... | https://en.wikipedia.org/wiki?curid=22303 |
24,020 | Polish alchemist, philosopher, and physician Michael Sendivogius (Michał Sędziwój) in his work "De Lapide Philosophorum Tractatus duodecim e naturae fonte et manuali experientia depromti" (1604) described a substance contained in air, referring to it as 'cibus vitae' (food of life,) and according to Polish historian Ro... | https://en.wikipedia.org/wiki?curid=22303 |
24,021 | It is also commonly claimed that oxygen was first discovered by Swedish pharmacist Carl Wilhelm Scheele. He had produced oxygen gas by heating mercuric oxide (HgO) and various nitrates in 1771–72. Scheele called the gas "fire air" because it was then the only known agent to support combustion. He wrote an account of th... | https://en.wikipedia.org/wiki?curid=22303 |
24,022 | In the meantime, on August 1, 1774, an experiment conducted by the British clergyman Joseph Priestley focused sunlight on mercuric oxide contained in a glass tube, which liberated a gas he named "dephlogisticated air". He noted that candles burned brighter in the gas and that a mouse was more active and lived longer wh... | https://en.wikipedia.org/wiki?curid=22303 |
24,023 | The French chemist Antoine Laurent Lavoisier later claimed to have discovered the new substance independently. Priestley visited Lavoisier in October 1774 and told him about his experiment and how he liberated the new gas. Scheele had also dispatched a letter to Lavoisier on September 30, 1774, which described his disc... | https://en.wikipedia.org/wiki?curid=22303 |
24,024 | Lavoisier conducted the first adequate quantitative experiments on oxidation and gave the first correct explanation of how combustion works. He used these and similar experiments, all started in 1774, to discredit the phlogiston theory and to prove that the substance discovered by Priestley and Scheele was a chemical e... | https://en.wikipedia.org/wiki?curid=22303 |
24,025 | In one experiment, Lavoisier observed that there was no overall increase in weight when tin and air were heated in a closed container. He noted that air rushed in when he opened the container, which indicated that part of the trapped air had been consumed. He also noted that the tin had increased in weight and that inc... | https://en.wikipedia.org/wiki?curid=22303 |
24,026 | Lavoisier renamed 'vital air' to "oxygène" in 1777 from the Greek roots " (oxys)" (acid, literally "sharp", from the taste of acids) and "-γενής (-genēs)" (producer, literally begetter), because he mistakenly believed that oxygen was a constituent of all acids. Chemists (such as Sir Humphry Davy in 1812) eventually det... | https://en.wikipedia.org/wiki?curid=22303 |
24,027 | "Oxygen" entered the English language despite opposition by English scientists and the fact that the Englishman Priestley had first isolated the gas and written about it. This is partly due to a poem praising the gas titled "Oxygen" in the popular book "The Botanic Garden" (1791) by Erasmus Darwin, grandfather of Charl... | https://en.wikipedia.org/wiki?curid=22303 |
24,028 | John Dalton's original atomic hypothesis presumed that all elements were monatomic and that the atoms in compounds would normally have the simplest atomic ratios with respect to one another. For example, Dalton assumed that water's formula was HO, leading to the conclusion that the atomic mass of oxygen was 8 times tha... | https://en.wikipedia.org/wiki?curid=22303 |
24,029 | The first commercial method of producing oxygen was chemical, the so-called Brin process involving a reversible reaction of barium oxide. It was invented in 1852 and commercialized in 1884, but was displaced by newer methods in early 20th century. | https://en.wikipedia.org/wiki?curid=22303 |
24,030 | By the late 19th century scientists realized that air could be liquefied and its components isolated by compressing and cooling it. Using a cascade method, Swiss chemist and physicist Raoul Pierre Pictet evaporated liquid sulfur dioxide in order to liquefy carbon dioxide, which in turn was evaporated to cool oxygen gas... | https://en.wikipedia.org/wiki?curid=22303 |
24,031 | In 1891 Scottish chemist James Dewar was able to produce enough liquid oxygen for study. The first commercially viable process for producing liquid oxygen was independently developed in 1895 by German engineer Carl von Linde and British engineer William Hampson. Both men lowered the temperature of air until it liquefie... | https://en.wikipedia.org/wiki?curid=22303 |
24,032 | In 1923, the American scientist Robert H. Goddard became the first person to develop a rocket engine that burned liquid fuel; the engine used gasoline for fuel and liquid oxygen as the oxidizer. Goddard successfully flew a small liquid-fueled rocket 56 m at 97 km/h on March 16, 1926, in Auburn, Massachusetts, US. | https://en.wikipedia.org/wiki?curid=22303 |
24,033 | In academic laboratories, oxygen can be prepared by heating together potassium chlorate mixed with a small proportion of manganese dioxide. | https://en.wikipedia.org/wiki?curid=22303 |
24,034 | Oxygen levels in the atmosphere are trending slightly downward globally, possibly because of fossil-fuel burning. | https://en.wikipedia.org/wiki?curid=22303 |
24,035 | At standard temperature and pressure, oxygen is a colorless, odorless, and tasteless gas with the molecular formula , referred to as dioxygen. | https://en.wikipedia.org/wiki?curid=22303 |
24,036 | As "dioxygen", two oxygen atoms are chemically bound to each other. The bond can be variously described based on level of theory, but is reasonably and simply described as a covalent double bond that results from the filling of molecular orbitals formed from the atomic orbitals of the individual oxygen atoms, the filli... | https://en.wikipedia.org/wiki?curid=22303 |
24,037 | This combination of cancellations and σ and π overlaps results in dioxygen's double-bond character and reactivity, and a triplet electronic ground state. An electron configuration with two unpaired electrons, as is found in dioxygen orbitals (see the filled π* orbitals in the diagram) that are of equal energy—i.e., deg... | https://en.wikipedia.org/wiki?curid=22303 |
24,038 | In the triplet form, molecules are paramagnetic. That is, they impart magnetic character to oxygen when it is in the presence of a magnetic field, because of the spin magnetic moments of the unpaired electrons in the molecule, and the negative exchange energy between neighboring molecules. Liquid oxygen is so magnetic ... | https://en.wikipedia.org/wiki?curid=22303 |
24,039 | Singlet oxygen is a name given to several higher-energy species of molecular in which all the electron spins are paired. It is much more reactive with common organic molecules than is normal (triplet) molecular oxygen. In nature, singlet oxygen is commonly formed from water during photosynthesis, using the energy of su... | https://en.wikipedia.org/wiki?curid=22303 |
24,040 | The common allotrope of elemental oxygen on Earth is called dioxygen, , the major part of the Earth's atmospheric oxygen (see Occurrence). O has a bond length of 121 pm and a bond energy of 498 kJ/mol. O is used by complex forms of life, such as animals, in cellular respiration. Other aspects of are covered in the rema... | https://en.wikipedia.org/wiki?curid=22303 |
24,041 | Trioxygen () is usually known as ozone and is a very reactive allotrope of oxygen that is damaging to lung tissue. Ozone is produced in the upper atmosphere when combines with atomic oxygen made by the splitting of by ultraviolet (UV) radiation. Since ozone absorbs strongly in the UV region of the spectrum, the ozone l... | https://en.wikipedia.org/wiki?curid=22303 |
24,042 | The metastable molecule tetraoxygen () was discovered in 2001, and was assumed to exist in one of the six phases of solid oxygen. It was proven in 2006 that this phase, created by pressurizing to 20 GPa, is in fact a rhombohedral cluster. This cluster has the potential to be a much more powerful oxidizer than either or... | https://en.wikipedia.org/wiki?curid=22303 |
24,043 | Oxygen dissolves more readily in water than in nitrogen, and in freshwater more readily than in seawater. Water in equilibrium with air contains approximately 1 molecule of dissolved for every 2 molecules of (1:2), compared with an atmospheric ratio of approximately 1:4. The solubility of oxygen in water is temperature... | https://en.wikipedia.org/wiki?curid=22303 |
24,044 | Oxygen condenses at 90.20 K (−182.95 °C, −297.31 °F) and freezes at 54.36 K (−218.79 °C, −361.82 °F). Both liquid and solid are clear substances with a light sky-blue color caused by absorption in the red (in contrast with the blue color of the sky, which is due to Rayleigh scattering of blue light). High-purity liquid... | https://en.wikipedia.org/wiki?curid=22303 |
24,045 | The spectroscopy of molecular oxygen is associated with the atmospheric processes of aurora and airglow. The absorption in the Herzberg continuum and Schumann–Runge bands in the ultraviolet produces atomic oxygen that is important in the chemistry of the middle atmosphere. Excited-state singlet molecular oxygen is resp... | https://en.wikipedia.org/wiki?curid=22303 |
24,046 | Naturally occurring oxygen is composed of three stable isotopes, O, O, and O, with O being the most abundant (99.762% natural abundance). | https://en.wikipedia.org/wiki?curid=22303 |
24,047 | Most O is synthesized at the end of the helium fusion process in massive stars but some is made in the neon burning process. O is primarily made by the burning of hydrogen into helium during the CNO cycle, making it a common isotope in the hydrogen burning zones of stars. Most O is produced when N (made abundant from C... | https://en.wikipedia.org/wiki?curid=22303 |
24,048 | Fourteen radioisotopes have been characterized. The most stable are O with a half-life of 122.24 seconds and O with a half-life of 70.606 seconds. All of the remaining radioactive isotopes have half-lives that are less than 27 s and the majority of these have half-lives that are less than 83 milliseconds. The most comm... | https://en.wikipedia.org/wiki?curid=22303 |
24,049 | Oxygen is the most abundant chemical element by mass in the Earth's biosphere, air, sea and land. Oxygen is the third most abundant chemical element in the universe, after hydrogen and helium. About 0.9% of the Sun's mass is oxygen. Oxygen constitutes 49.2% of the Earth's crust by mass as part of oxide compounds such a... | https://en.wikipedia.org/wiki?curid=22303 |
24,050 | The unusually high concentration of oxygen gas on Earth is the result of the oxygen cycle. This biogeochemical cycle describes the movement of oxygen within and between its three main reservoirs on Earth: the atmosphere, the biosphere, and the lithosphere. The main driving factor of the oxygen cycle is photosynthesis, ... | https://en.wikipedia.org/wiki?curid=22303 |
24,051 | Free oxygen also occurs in solution in the world's water bodies. The increased solubility of at lower temperatures (see Physical properties) has important implications for ocean life, as polar oceans support a much higher density of life due to their higher oxygen content. Water polluted with plant nutrients such as ni... | https://en.wikipedia.org/wiki?curid=22303 |
24,052 | Paleoclimatologists measure the ratio of oxygen-18 and oxygen-16 in the shells and skeletons of marine organisms to determine the climate millions of years ago (see oxygen isotope ratio cycle). Seawater molecules that contain the lighter isotope, oxygen-16, evaporate at a slightly faster rate than water molecules conta... | https://en.wikipedia.org/wiki?curid=22303 |
24,053 | Planetary geologists have measured the relative quantities of oxygen isotopes in samples from the Earth, the Moon, Mars, and meteorites, but were long unable to obtain reference values for the isotope ratios in the Sun, believed to be the same as those of the primordial solar nebula. Analysis of a silicon wafer exposed... | https://en.wikipedia.org/wiki?curid=22303 |
24,054 | Oxygen presents two spectrophotometric absorption bands peaking at the wavelengths 687 and 760 nm. Some remote sensing scientists have proposed using the measurement of the radiance coming from vegetation canopies in those bands to characterize plant health status from a satellite platform. This approach exploits the f... | https://en.wikipedia.org/wiki?curid=22303 |
24,055 | In nature, free oxygen is produced by the light-driven splitting of water during oxygenic photosynthesis. According to some estimates, green algae and cyanobacteria in marine environments provide about 70% of the free oxygen produced on Earth, and the rest is produced by terrestrial plants. Other estimates of the ocean... | https://en.wikipedia.org/wiki?curid=22303 |
24,056 | Photolytic oxygen evolution occurs in the thylakoid membranes of photosynthetic organisms and requires the energy of four photons. Many steps are involved, but the result is the formation of a proton gradient across the thylakoid membrane, which is used to synthesize adenosine triphosphate (ATP) via photophosphorylatio... | https://en.wikipedia.org/wiki?curid=22303 |
24,057 | Oxygen is used in mitochondria in the generation of ATP during oxidative phosphorylation. The reaction for aerobic respiration is essentially the reverse of photosynthesis and is simplified as | https://en.wikipedia.org/wiki?curid=22303 |
24,058 | In vertebrates, diffuses through membranes in the lungs and into red blood cells. Hemoglobin binds , changing color from bluish red to bright red ( is released from another part of hemoglobin through the Bohr effect). Other animals use hemocyanin (molluscs and some arthropods) or hemerythrin (spiders and lobsters). A l... | https://en.wikipedia.org/wiki?curid=22303 |
24,059 | Until the discovery of anaerobic metazoa, oxygen was thought to be a requirement for all complex life. | https://en.wikipedia.org/wiki?curid=22303 |
24,060 | Reactive oxygen species, such as superoxide ion () and hydrogen peroxide (), are reactive by-products of oxygen use in organisms. Parts of the immune system of higher organisms create peroxide, superoxide, and singlet oxygen to destroy invading microbes. Reactive oxygen species also play an important role in the hypers... | https://en.wikipedia.org/wiki?curid=22303 |
24,061 | An adult human at rest inhales 1.8 to 2.4 grams of oxygen per minute. This amounts to more than 6 billion tonnes of oxygen inhaled by humanity per year. | https://en.wikipedia.org/wiki?curid=22303 |
24,062 | The free oxygen partial pressure in the body of a living vertebrate organism is highest in the respiratory system, and decreases along any arterial system, peripheral tissues, and venous system, respectively. Partial pressure is the pressure that oxygen would have if it alone occupied the volume. | https://en.wikipedia.org/wiki?curid=22303 |
24,063 | Free oxygen gas was almost nonexistent in Earth's atmosphere before photosynthetic archaea and bacteria evolved, probably about 3.5 billion years ago. Free oxygen first appeared in significant quantities during the Paleoproterozoic eon (between 3.0 and 2.3 billion years ago). Even if there was much dissolved iron in th... | https://en.wikipedia.org/wiki?curid=22303 |
24,064 | The presence of large amounts of dissolved and free oxygen in the oceans and atmosphere may have driven most of the extant anaerobic organisms to extinction during the Great Oxygenation Event ("oxygen catastrophe") about 2.4 billion years ago. Cellular respiration using enables aerobic organisms to produce much more AT... | https://en.wikipedia.org/wiki?curid=22303 |
24,065 | Since the beginning of the Cambrian period 540 million years ago, atmospheric levels have fluctuated between 15% and 30% by volume. Towards the end of the Carboniferous period (about 300 million years ago) atmospheric levels reached a maximum of 35% by volume, which may have contributed to the large size of insects and... | https://en.wikipedia.org/wiki?curid=22303 |
24,066 | Variations in atmospheric oxygen concentration have shaped past climates. When oxygen declined, atmospheric density dropped, which in turn increased surface evaporation, causing precipitation increases and warmer temperatures. | https://en.wikipedia.org/wiki?curid=22303 |
24,067 | At the current rate of photosynthesis it would take about 2,000 years to regenerate the entire in the present atmosphere. | https://en.wikipedia.org/wiki?curid=22303 |
24,068 | In the field of astrobiology and in the search for extraterrestrial life oxygen is a strong biosignature. That said it might not be a definite biosignature, being possibly produced abiotically on celestial bodies with processes and conditions (such as a peculiar hydrosphere) which allow free oxygen, like with Europa's ... | https://en.wikipedia.org/wiki?curid=22303 |
24,069 | One hundred million tonnes of are extracted from air for industrial uses annually by two primary methods. The most common method is fractional distillation of liquefied air, with distilling as a vapor while is left as a liquid. | https://en.wikipedia.org/wiki?curid=22303 |
24,070 | The other primary method of producing is passing a stream of clean, dry air through one bed of a pair of identical zeolite molecular sieves, which absorbs the nitrogen and delivers a gas stream that is 90% to 93% . Simultaneously, nitrogen gas is released from the other nitrogen-saturated zeolite bed, by reducing the c... | https://en.wikipedia.org/wiki?curid=22303 |
24,071 | Oxygen gas can also be produced through electrolysis of water into molecular oxygen and hydrogen. DC electricity must be used: if AC is used, the gases in each limb consist of hydrogen and oxygen in the explosive ratio 2:1. A similar method is the electrocatalytic evolution from oxides and oxoacids. Chemical catalysts ... | https://en.wikipedia.org/wiki?curid=22303 |
24,072 | Oxygen storage methods include high-pressure oxygen tanks, cryogenics and chemical compounds. For reasons of economy, oxygen is often transported in bulk as a liquid in specially insulated tankers, since one liter of liquefied oxygen is equivalent to 840 liters of gaseous oxygen at atmospheric pressure and . Such tanke... | https://en.wikipedia.org/wiki?curid=22303 |
24,073 | Uptake of from the air is the essential purpose of respiration, so oxygen supplementation is used in medicine. Treatment not only increases oxygen levels in the patient's blood, but has the secondary effect of decreasing resistance to blood flow in many types of diseased lungs, easing work load on the heart. Oxygen the... | https://en.wikipedia.org/wiki?curid=22303 |
24,074 | Treatments are flexible enough to be used in hospitals, the patient's home, or increasingly by portable devices. Oxygen tents were once commonly used in oxygen supplementation, but have since been replaced mostly by the use of oxygen masks or nasal cannulas. | https://en.wikipedia.org/wiki?curid=22303 |
24,075 | Hyperbaric (high-pressure) medicine uses special oxygen chambers to increase the partial pressure of around the patient and, when needed, the medical staff. Carbon monoxide poisoning, gas gangrene, and decompression sickness (the 'bends') are sometimes addressed with this therapy. Increased concentration in the lungs h... | https://en.wikipedia.org/wiki?curid=22303 |
24,076 | An application of as a low-pressure breathing gas is in modern space suits, which surround their occupant's body with the breathing gas. These devices use nearly pure oxygen at about one-third normal pressure, resulting in a normal blood partial pressure of . This trade-off of higher oxygen concentration for lower pres... | https://en.wikipedia.org/wiki?curid=22303 |
24,077 | Scuba and surface-supplied underwater divers and submariners also rely on artificially delivered . Submarines, submersibles and atmospheric diving suits usually operate at normal atmospheric pressure. Breathing air is scrubbed of carbon dioxide by chemical extraction and oxygen is replaced to maintain a constant partia... | https://en.wikipedia.org/wiki?curid=22303 |
24,078 | People who climb mountains or fly in non-pressurized fixed-wing aircraft sometimes have supplemental supplies. Pressurized commercial airplanes have an emergency supply of automatically supplied to the passengers in case of cabin depressurization. Sudden cabin pressure loss activates chemical oxygen generators above ea... | https://en.wikipedia.org/wiki?curid=22303 |
24,079 | Oxygen, as a mild euphoric, has a history of recreational use in oxygen bars and in sports. Oxygen bars are establishments found in the United States since the late 1990s that offer higher than normal exposure for a minimal fee. Professional athletes, especially in American football, sometimes go off-field between play... | https://en.wikipedia.org/wiki?curid=22303 |
24,080 | Other recreational uses that do not involve breathing include pyrotechnic applications, such as George Goble's five-second ignition of barbecue grills. | https://en.wikipedia.org/wiki?curid=22303 |
24,081 | Smelting of iron ore into steel consumes 55% of commercially produced oxygen. In this process, is injected through a high-pressure lance into molten iron, which removes sulfur impurities and excess carbon as the respective oxides, and . The reactions are exothermic, so the temperature increases to 1,700 °C. | https://en.wikipedia.org/wiki?curid=22303 |
24,082 | Another 25% of commercially produced oxygen is used by the chemical industry. Ethylene is reacted with to create ethylene oxide, which, in turn, is converted into ethylene glycol; the primary feeder material used to manufacture a host of products, including antifreeze and polyester polymers (the precursors of many plas... | https://en.wikipedia.org/wiki?curid=22303 |
24,083 | Most of the remaining 20% of commercially produced oxygen is used in medical applications, metal cutting and welding, as an oxidizer in rocket fuel, and in water treatment. Oxygen is used in oxyacetylene welding, burning acetylene with to produce a very hot flame. In this process, metal up to thick is first heated with... | https://en.wikipedia.org/wiki?curid=22303 |
24,084 | The oxidation state of oxygen is −2 in almost all known compounds of oxygen. The oxidation state −1 is found in a few compounds such as peroxides. Compounds containing oxygen in other oxidation states are very uncommon: −1/2 (superoxides), −1/3 (ozonides), 0 (elemental, hypofluorous acid), +1/2 (dioxygenyl), +1 (dioxyg... | https://en.wikipedia.org/wiki?curid=22303 |
24,085 | Water () is an oxide of hydrogen and the most familiar oxygen compound. Hydrogen atoms are covalently bonded to oxygen in a water molecule but also have an additional attraction (about 23.3 kJ/mol per hydrogen atom) to an adjacent oxygen atom in a separate molecule. These hydrogen bonds between water molecules hold the... | https://en.wikipedia.org/wiki?curid=22303 |
24,086 | Due to its electronegativity, oxygen forms chemical bonds with almost all other elements to give corresponding oxides. The surface of most metals, such as aluminium and titanium, are oxidized in the presence of air and become coated with a thin film of oxide that passivates the metal and slows further corrosion. Many o... | https://en.wikipedia.org/wiki?curid=22303 |
24,087 | Oxygen is present in the atmosphere in trace quantities in the form of carbon dioxide (). The Earth's crustal rock is composed in large part of oxides of silicon (silica , as found in granite and quartz), aluminium (aluminium oxide , in bauxite and corundum), iron (iron(III) oxide , in hematite and rust), and calcium c... | https://en.wikipedia.org/wiki?curid=22303 |
24,088 | Oxygen also acts as a ligand for transition metals, forming transition metal dioxygen complexes, which feature metal–. This class of compounds includes the heme proteins hemoglobin and myoglobin. An exotic and unusual reaction occurs with , which oxidizes oxygen to give OPtF, dioxygenyl hexafluoroplatinate. | https://en.wikipedia.org/wiki?curid=22303 |
24,089 | Among the most important classes of organic compounds that contain oxygen are (where "R" is an organic group): alcohols (R-OH); ethers (R-O-R); ketones (R-CO-R); aldehydes (R-CO-H); carboxylic acids (R-COOH); esters (R-COO-R); acid anhydrides (R-CO-O-CO-R); and amides (). There are many important organic solvents that ... | https://en.wikipedia.org/wiki?curid=22303 |
24,090 | Oxygen reacts spontaneously with many organic compounds at or below room temperature in a process called autoxidation. Most of the organic compounds that contain oxygen are not made by direct action of . Organic compounds important in industry and commerce that are made by direct oxidation of a precursor include ethyle... | https://en.wikipedia.org/wiki?curid=22303 |
24,091 | The NFPA 704 standard rates compressed oxygen gas as nonhazardous to health, nonflammable and nonreactive, but an oxidizer. Refrigerated liquid oxygen (LOX) is given a health hazard rating of 3 (for increased risk of hyperoxia from condensed vapors, and for hazards common to cryogenic liquids such as frostbite), and al... | https://en.wikipedia.org/wiki?curid=22303 |
24,092 | Oxygen gas () can be toxic at elevated partial pressures, leading to convulsions and other health problems. Oxygen toxicity usually begins to occur at partial pressures more than 50 kilopascals (kPa), equal to about 50% oxygen composition at standard pressure or 2.5 times the normal sea-level partial pressure of about ... | https://en.wikipedia.org/wiki?curid=22303 |
24,093 | At one time, premature babies were placed in incubators containing -rich air, but this practice was discontinued after some babies were blinded by the oxygen content being too high. | https://en.wikipedia.org/wiki?curid=22303 |
24,094 | Breathing pure in space applications, such as in some modern space suits, or in early spacecraft such as Apollo, causes no damage due to the low total pressures used. In the case of spacesuits, the partial pressure in the breathing gas is, in general, about 30 kPa (1.4 times normal), and the resulting partial pressure ... | https://en.wikipedia.org/wiki?curid=22303 |
24,095 | Oxygen toxicity to the lungs and central nervous system can also occur in deep scuba diving and surface supplied diving. Prolonged breathing of an air mixture with an partial pressure more than 60 kPa can eventually lead to permanent pulmonary fibrosis. Exposure to an partial pressures greater than 160 kPa (about 1.6 a... | https://en.wikipedia.org/wiki?curid=22303 |
24,096 | Highly concentrated sources of oxygen promote rapid combustion. Fire and explosion hazards exist when concentrated oxidants and fuels are brought into close proximity; an ignition event, such as heat or a spark, is needed to trigger combustion. Oxygen is the oxidant, not the fuel. | https://en.wikipedia.org/wiki?curid=22303 |
24,097 | Concentrated will allow combustion to proceed rapidly and energetically. Steel pipes and storage vessels used to store and transmit both gaseous and liquid oxygen will act as a fuel; and therefore the design and manufacture of systems requires special training to ensure that ignition sources are minimized. The fire tha... | https://en.wikipedia.org/wiki?curid=22303 |
24,098 | Liquid oxygen spills, if allowed to soak into organic matter, such as wood, petrochemicals, and asphalt can cause these materials to detonate unpredictably on subsequent mechanical impact. | https://en.wikipedia.org/wiki?curid=22303 |
24,099 | Metformin, sold under the brand name Glucophage, among others, is the main first-line medication for the treatment of type 2 diabetes, particularly in people who are overweight. It is also used in the treatment of polycystic ovary syndrome. It is not associated with weight gain and is taken by mouth. It is sometimes us... | https://en.wikipedia.org/wiki?curid=253720 |
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