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111-542: Mineral resources of the Artillery Mountains include manganese , uranium and gold . Rocher Deboule Minerals drilled their Artillery Mountains Manganese property in 2008, and discovered a resource of 2,553,000 tonnes of 3.82% Mn. High Desert Gold acquired the Artillery Peak gold project in western Arizona in 2008. At Uranium Energy 's Artillery Peak uranium project, the firm hopes to discover

222-459: A free balloon flight. He found the ionization rate increased to twice the rate at ground level. Hess ruled out the Sun as the radiation's source by making a balloon ascent during a near-total eclipse. With the moon blocking much of the Sun's visible radiation, Hess still measured rising radiation at rising altitudes. He concluded that "The results of the observations seem most likely to be explained by

333-409: A magnesia nigra (the black ore) from magnesia alba (a white ore, also from Magnesia, also useful in glassmaking). Michele Mercati called magnesia nigra manganesa , and finally the metal isolated from it became known as manganese ( German : Mangan ). The name magnesia eventually was then used to refer only to the white magnesia alba (magnesium oxide), which provided the name magnesium for

444-459: A balloon. On 1 April 1935, he took measurements at heights up to 13.6 kilometres using a pair of Geiger counters in an anti-coincidence circuit to avoid counting secondary ray showers. Homi J. Bhabha derived an expression for the probability of scattering positrons by electrons, a process now known as Bhabha scattering . His classic paper, jointly with Walter Heitler , published in 1937 described how primary cosmic rays from space interact with

555-463: A characteristic energy maximum of 2 GeV, indicating their production in a fundamentally different process from cosmic ray protons, which on average have only one-sixth of the energy. There is no evidence of complex antimatter atomic nuclei, such as antihelium nuclei (i.e., anti-alpha particles), in cosmic rays. These are actively being searched for. A prototype of the AMS-02 designated AMS-01 ,

666-585: A decay of primary cosmic rays as they impact an atmosphere, include photons, hadrons , and leptons , such as electrons , positrons, muons, and pions . The latter three of these were first detected in cosmic rays. Primary cosmic rays mostly originate from outside the Solar System and sometimes even outside the Milky Way . When they interact with Earth's atmosphere, they are converted to secondary particles. The mass ratio of helium to hydrogen nuclei, 28%,

777-444: A difference between the intensities of cosmic rays arriving from the east and the west that depends upon the charge of the primary particles—the so-called "east–west effect". Three independent experiments found that the intensity is, in fact, greater from the west, proving that most primaries are positive. During the years from 1930 to 1945, a wide variety of investigations confirmed that the primary cosmic rays are mostly protons, and

888-506: A few antiprotons in primary cosmic rays, amounting to less than 1% of the particles in primary cosmic rays. These do not appear to be the products of large amounts of antimatter from the Big Bang, or indeed complex antimatter in the universe. Rather, they appear to consist of only these two elementary particles, newly made in energetic processes. Preliminary results from the presently operating Alpha Magnetic Spectrometer ( AMS-02 ) on board

999-429: A fungicide. Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. It is found mostly in the bones, but also the liver, kidneys, and brain. In the human brain, the manganese is bound to manganese metalloproteins , most notably glutamine synthetase in astrocytes . It

1110-607: A lesser extent as rhodochrosite ( MnCO 3 ). The most important manganese ore is pyrolusite ( MnO 2 ). Other economically important manganese ores usually show a close spatial relation to the iron ores, such as sphalerite . Land-based resources are large but irregularly distributed. About 80% of the known world manganese resources are in South Africa; other important manganese deposits are in Ukraine, Australia, India, China, Gabon and Brazil. According to 1978 estimate,

1221-442: A primitive cubic structure with 20 atoms per unit cell at two types of sites, which is as complex as that of any other elemental metal. It is easily obtained as a metastable phase at room temperature by rapid quenching. It does not show magnetic ordering , remaining paramagnetic down to the lowest temperature measured (1.1 K). Gamma manganese (γ-Mn) forms when heated above 1,370 K (1,100 °C; 2,010 °F). It has

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1332-501: A secondary shower of particles in multiple detectors at the same time is an indication that all of the particles came from that event. Cosmic rays impacting other planetary bodies in the Solar System are detected indirectly by observing high-energy gamma ray emissions by gamma-ray telescope. These are distinguished from radioactive decay processes by their higher energies above about 10 MeV. The flux of incoming cosmic rays at

1443-447: A simple face-centered cubic structure (four atoms per unit cell). When quenched to room temperature it converts to β-Mn, but it can be stabilized at room temperature by alloying it with at least 5 percent of other elements (such as C, Fe, Ni, Cu, Pd or Au), and these solute-stabilized alloys distort into a face-centered tetragonal structure. Delta manganese (δ-Mn) forms when heated above 1,406 K (1,130 °C; 2,070 °F) and

1554-413: A single power law", suggesting a more complex process of cosmic ray formation. In February 2013, though, research analyzing data from Fermi revealed through an observation of neutral pion decay that supernovae were indeed a source of cosmic rays, with each explosion producing roughly 3 × 10 – 3 × 10   J of cosmic rays. Supernovae do not produce all cosmic rays, however, and

1665-518: A so-called air shower secondary radiation that rains down, including x-rays , protons, alpha particles, pions, muons, electrons, neutrinos, and neutrons . All of the secondary particles produced by the collision continue onward on paths within about one degree of the primary particle's original path. Typical particles produced in such collisions are neutrons and charged mesons such as positive or negative pions and kaons . Some of these subsequently decay into muons and neutrinos, which are able to reach

1776-470: A source of cosmic rays. Subsequently, Sekido et al. (1951) identified the Crab Nebula as a source of cosmic rays. Since then, a wide variety of potential sources for cosmic rays began to surface, including supernovae , active galactic nuclei, quasars , and gamma-ray bursts . Later experiments have helped to identify the sources of cosmic rays with greater certainty. In 2009, a paper presented at

1887-455: A uranium deposit similar to the nearby Anderson Mine , which has a published reserve of 27 million pounds of uranium, in addition to a uranium resource of 70 million pounds, and another 80 million pounds of vanadium . 34°22′04″N 113°36′04″W  /  34.3677961°N 113.6010425°W  / 34.3677961; -113.6010425 Manganese Manganese is a chemical element ; it has symbol Mn and atomic number 25. It

1998-436: Is MnO 2 . It is the dark brown pigment of many cave drawings but is also a common ingredient in dry cell batteries. Complexes of Mn(IV) are well known, but they require elaborate ligands . Mn(IV)-OH complexes are an intermediate in some enzymes , including the oxygen evolving center (OEC) in plants. Simple derivatives Mn are rarely encountered but can be stabilized by suitably basic ligands. Manganese(III) acetate

2109-466: Is a brown pigment for paint and is a constituent of natural umber . Tetravalent manganese is used as an activator in red-emitting phosphors . While many compounds are known which show luminescence , the majority are not used in commercial application due to low efficiency or deep red emission. However, several Mn activated fluorides were reported as potential red-emitting phosphors for warm-white LEDs. But to this day, only K 2 SiF 6 :Mn

2220-552: Is a commonly used laboratory reagent because of its oxidizing properties; it is used as a topical medicine (for example, in the treatment of fish diseases). Solutions of potassium permanganate were among the first stains and fixatives to be used in the preparation of biological cells and tissues for electron microscopy. Aside from various permanganate salts, Mn(VII) is represented by the unstable, volatile derivative Mn 2 O 7 . Oxyhalides (MnO 3 F and MnO 3 Cl) are powerful oxidizing agents . The most prominent example of Mn in

2331-457: Is a hard, brittle, silvery metal, often found in minerals in combination with iron . Manganese was first isolated in the 1770s. It is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels . It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent; as a rubber additive; and in glass making, fertilisers, and ceramics. Manganese sulfate can be used as

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2442-453: Is also responsible for the abundances of scandium , titanium , vanadium , and manganese ions in cosmic rays produced by collisions of iron and nickel nuclei with interstellar matter . At high energies the composition changes and heavier nuclei have larger abundances in some energy ranges. Current experiments aim at more accurate measurements of the composition at high energies. Satellite experiments have found evidence of positrons and

2553-549: Is also seen in the mineral rhodochrosite ( manganese(II) carbonate ). Manganese(II) commonly exists with a high spin, S = 5/2 ground state because of the high pairing energy for manganese(II). There are no spin-allowed d–d transitions in manganese(II), which explain its faint color. Manganese forms a large variety of organometallic derivatives, i.e., compounds with Mn-C bonds. The organometallic derivatives include numerous examples of Mn in its lower oxidation states, i.e. Mn(−III) up through Mn(I). This area of organometallic chemistry

2664-407: Is an area of active research. An active search from Earth orbit for anti-alpha particles as of 2019 had found no unequivocal evidence. Upon striking the atmosphere, cosmic rays violently burst atoms into other bits of matter, producing large amounts of pions and muons (produced from the decay of charged pions , which have a short half-life) as well as neutrinos . The neutron composition of

2775-574: Is an oxidant useful in organic synthesis . Solid compounds of manganese(III) are characterized by its strong purple-red color and a preference for distorted octahedral coordination resulting from the Jahn-Teller effect . A particularly common oxidation state for manganese in aqueous solution is +2, which has a pale pink color. Many manganese(II) compounds are known, such as the aquo complexes derived from manganese(II) sulfate (MnSO 4 ) and manganese(II) chloride (MnCl 2 ). This oxidation state

2886-464: Is attractive because Mn is inexpensive and of relatively low toxicity. Of greatest commercial interest is "MMT", methylcyclopentadienyl manganese tricarbonyl , which is used as an anti-knock compound added to gasoline (petrol) in some countries. It features Mn(I). Consistent with other aspects of Mn(II) chemistry, manganocene ( Mn(C 5 H 5 ) 2 ) is high-spin. In contrast, its neighboring metal iron forms an air-stable, low-spin derivative in

2997-556: Is commercially available for use in warm-white LEDs . Cosmic rays Cosmic rays or astroparticles are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei ) that move through space at nearly the speed of light . They originate from the Sun , from outside of the Solar System in our own galaxy, and from distant galaxies. Upon impact with Earth's atmosphere , cosmic rays produce showers of secondary particles , some of which reach

3108-483: Is composed of one stable isotope , Mn. Several radioisotopes have been isolated and described, ranging in atomic weight from 46 u ( Mn) to 72 u ( Mn). The most stable are Mn with a half-life of 3.7 million years, Mn with a half-life of 312.2 days, and Mn with a half-life of 5.591 days. All of the remaining radioactive isotopes have half-lives of less than three hours, and the majority of less than one minute. The primary decay mode in isotopes lighter than

3219-421: Is dominant in a given soil. At pH values less than 6 or under anaerobic conditions, Mn(II) dominates, while under more alkaline and aerobic conditions, Mn(III,IV) oxides and hydroxides predominate. These effects of soil acidity and aeration state on the form of Mn can be modified or controlled by microbial activity. Microbial respiration can cause both the oxidation of Mn to the oxides, and it can cause reduction of

3330-586: Is familiar in the laboratory in the form of the deep violet salt potassium permanganate . It occurs at the active sites in some enzymes . Of particular interest is the use of a Mn-O cluster , the oxygen-evolving complex , in the production of oxygen by plants. Manganese is a silvery-gray metal that resembles iron. It is hard and very brittle, difficult to fuse, but easy to oxidize. Manganese and its common ions are paramagnetic . Manganese tarnishes slowly in air and oxidizes ("rusts") like iron in water containing dissolved oxygen. Naturally occurring manganese

3441-545: Is found throughout the world's oceans, 90% of which originates from hydrothermal vents. Particulate Mn develops in buoyant plumes over an active vent source, while the dMn behaves conservatively. Mn concentrations vary between the water columns of the ocean. At the surface, dMn is elevated due to input from external sources such as rivers, dust, and shelf sediments. Coastal sediments normally have lower Mn concentrations, but can increase due to anthropogenic discharges from industries such as mining and steel manufacturing, which enter

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3552-458: Is low spin, which contrasts with the high spin character of its precursor, MnBr 2 (dmpe) 2 ( dmpe = (CH 3 ) 2 PCH 2 CH 2 P(CH 3 ) 2 ). Polyalkyl and polyaryl derivatives of manganese often exist in higher oxidation states, reflecting the electron-releasing properties of alkyl and aryl ligands. One example is [Mn(CH 3 ) 6 ] . The origin of the name manganese is complex. In ancient times, two black minerals were identified from

3663-408: Is mainly mined in South Africa, Australia, China, Gabon, Brazil, India, Kazakhstan, Ghana, Ukraine and Malaysia. For the production of ferromanganese , the manganese ore is mixed with iron ore and carbon, and then reduced either in a blast furnace or in an electric arc furnace. The resulting ferromanganese has a manganese content of 30–80%. Pure manganese used for the production of iron-free alloys

3774-461: Is more accurate than indirect detection. However the flux of cosmic rays decreases with energy, which hampers direct detection for the energy range above 1 PeV. Both direct and indirect detection are realized by several techniques. Direct detection is possible by all kinds of particle detectors at the ISS , on satellites, or high-altitude balloons. However, there are constraints in weight and size limiting

3885-424: Is produced by leaching manganese ore with sulfuric acid and a subsequent electrowinning process. A more progressive extraction process involves directly reducing (a low grade) manganese ore by heap leaching . This is done by percolating natural gas through the bottom of the heap; the natural gas provides the heat (needs to be at least 850 °C) and the reducing agent (carbon monoxide). This reduces all of

3996-714: Is relatively rare, produced by cosmic rays impact on iron . Manganese isotopic contents are typically combined with chromium isotopic contents and have found application in isotope geology and radiometric dating . Mn–Cr isotopic ratios reinforce the evidence from Al and Pd for the early history of the Solar System . Variations in Cr/ Cr and Mn/Cr ratios from several meteorites suggest an initial Mn/ Mn ratio, which indicate that Mn–Cr isotopic composition must result from in situ decay of Mn in differentiated planetary bodies. Hence, Mn provides additional evidence for nucleosynthetic processes immediately before coalescence of

4107-486: Is similar to the primordial elemental abundance ratio of these elements, 24%. The remaining fraction is made up of the other heavier nuclei that are typical nucleosynthesis end products, primarily lithium , beryllium , and boron . These nuclei appear in cosmic rays in greater abundance (≈1%) than in the solar atmosphere, where they are only about 10 as abundant (by number) as helium . Cosmic rays composed of charged nuclei heavier than helium are called HZE ions . Due to

4218-442: Is stable up to the manganese melting point of 1,519 K (1,250 °C; 2,270 °F). It has a body-centered cubic structure (two atoms per cubic unit cell). Common oxidation states of manganese are +2, +3, +4, +6, and +7, although all oxidation states from −3 to +7 have been observed. Manganese in oxidation state +7 is represented by salts of the intensely purple permanganate anion MnO − 4 . Potassium permanganate

4329-405: Is unusual among elemental metals in having a very complex unit cell, with 58 atoms per cell (29 atoms per primitive unit cell) in four different types of site. It is paramagnetic at room temperature and antiferromagnetic at temperatures below 95 K (−178 °C). Beta manganese (β-Mn) forms when heated above the transition temperature of 973 K (700 °C; 1,290 °F). It has

4440-412: Is used as a reagent in organic chemistry for the oxidation of benzylic alcohols (where the hydroxyl group is adjacent to an aromatic ring ). Manganese dioxide has been used since antiquity to oxidize and neutralize the greenish tinge in glass from trace amounts of iron contamination. MnO 2 is also used in the manufacture of oxygen and chlorine and in drying black paints. In some preparations, it

4551-660: The Auger Project is currently operated at a site on the Pampas of Argentina by an international consortium of physicists. The project was first led by James Cronin , winner of the 1980 Nobel Prize in Physics from the University of Chicago , and Alan Watson of the University of Leeds , and later by scientists of the international Pierre Auger Collaboration. Their aim is to explore the properties and arrival directions of

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4662-695: The Fermi Space Telescope (2013) have been interpreted as evidence that a significant fraction of primary cosmic rays originate from the supernova explosions of stars. Based on observations of neutrinos and gamma rays from blazar TXS 0506+056 in 2018, active galactic nuclei also appear to produce cosmic rays. The term ray (as in optical ray ) seems to have arisen from an initial belief, due to their penetrating power, that cosmic rays were mostly electromagnetic radiation . Nevertheless, following wider recognition of cosmic rays as being various high-energy particles with intrinsic mass ,

4773-634: The International Cosmic Ray Conference by scientists at the Pierre Auger Observatory in Argentina showed ultra-high energy cosmic rays originating from a location in the sky very close to the radio galaxy Centaurus A , although the authors specifically stated that further investigation would be required to confirm Centaurus A as a source of cosmic rays. However, no correlation was found between

4884-639: The International Space Station show that positrons in the cosmic rays arrive with no directionality. In September 2014, new results with almost twice as much data were presented in a talk at CERN and published in Physical Review Letters. A new measurement of positron fraction up to 500 GeV was reported, showing that positron fraction peaks at a maximum of about 16% of total electron+positron events, around an energy of 275 ± 32 GeV . At higher energies, up to 500 GeV,

4995-496: The Middle Ages until modern times and is evident in 14th-century glass from Venice . Because it was used in glassmaking, manganese dioxide was available for experiments by alchemists, the first chemists. Ignatius Gottfried Kaim (1770) and Johann Glauber (17th century) discovered that manganese dioxide could be converted to permanganate , a useful laboratory reagent. Kaim also may have reduced manganese dioxide to isolate

5106-602: The Spartan steel exceptionally hard. Around the beginning of the 19th century, manganese was used in steelmaking and several patents were granted. In 1816, it was documented that iron alloyed with manganese was harder but not more brittle. In 1837, British academic James Couper noted an association between miners' heavy exposure to manganese and a form of Parkinson's disease . In 1912, United States patents were granted for protecting firearms against rust and corrosion with manganese phosphate electrochemical conversion coatings, and

5217-544: The centrifugal mechanism of acceleration in active galactic nuclei . At 50 joules [J] (3.1 × 10   GeV ), the highest-energy ultra-high-energy cosmic rays (such as the OMG particle recorded in 1991) have energies comparable to the kinetic energy of a 90- kilometre-per-hour [km/h] (56  mph ) baseball. As a result of these discoveries, there has been interest in investigating cosmic rays of even greater energies. Most cosmic rays, however, do not have such extreme energies;

5328-560: The cosmic microwave background (CMB) radiation energy density at ≈0.25 eV/cm . There are two main classes of detection methods. First, the direct detection of the primary cosmic rays in space or at high altitude by balloon-borne instruments. Second, the indirect detection of secondary particle, i.e., extensive air showers at higher energies. While there have been proposals and prototypes for space and balloon-borne detection of air showers, currently operating experiments for high-energy cosmic rays are ground based. Generally direct detection

5439-523: The ocean floor has 500 billion tons of manganese nodules . Attempts to find economically viable methods of harvesting manganese nodules were abandoned in the 1970s. In South Africa, most identified deposits are located near Hotazel in the Northern Cape Province , ( Kalahari manganese fields ), with a 2011 estimate of 15 billion tons. In 2011 South Africa produced 3.4 million tons, topping all other nations. Manganese

5550-551: The surface , although the bulk are deflected off into space by the magnetosphere or the heliosphere . Cosmic rays were discovered by Victor Hess in 1912 in balloon experiments, for which he was awarded the 1936 Nobel Prize in Physics . Direct measurement of cosmic rays, especially at lower energies, has been possible since the launch of the first satellites in the late 1950s. Particle detectors similar to those used in nuclear and high-energy physics are used on satellites and space probes for research into cosmic rays. Data from

5661-476: The +6 oxidation state is the green anion manganate , [MnO 4 ] . Manganate salts are intermediates in the extraction of manganese from its ores. Compounds with oxidation states +5 are somewhat elusive, and often found associated to an oxide (O ) or nitride (N ) ligand. One example is the blue anion hypomanganate [MnO 4 ] . Mn(IV) is somewhat enigmatic because it is common in nature but far rarer in synthetic chemistry. The most common Mn ore, pyrolusite ,

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5772-491: The 2020s. The real mission of Hughes Glomar Explorer was to raise a sunken Soviet submarine, the K-129 , with the goal of retrieving Soviet code books. An abundant resource of manganese in the form of manganese nodules found on the ocean floor. These nodules, which are composed of 29% manganese, are located along the ocean floor . The environmental impacts of nodule collection are of interest. Dissolved manganese (dMn)

5883-479: The 20th century, manganese dioxide was widely used as the cathodic for commercial disposable dry batteries of both the standard (zinc–carbon) and alkaline types. Manganese is essential to iron and steel production by virtue of its sulfur -fixing, deoxidizing , and alloying properties. This application was first recognized by the British metallurgist Robert Forester Mushet (1811–1891) who, in 1856, introduced

5994-639: The Netherlands, Jacob Clay found evidence, later confirmed in many experiments, that cosmic ray intensity increases from the tropics to mid-latitudes, which indicated that the primary cosmic rays are deflected by the geomagnetic field and must therefore be charged particles, not photons. In 1929, Bothe and Kolhörster discovered charged cosmic-ray particles that could penetrate 4.1 cm of gold. Charged particles of such high energy could not possibly be produced by photons from Millikan's proposed interstellar fusion process. In 1930, Bruno Rossi predicted

6105-502: The Pierre Auger Observatory is undergoing an upgrade to improve its accuracy and find evidence for the yet unconfirmed origin of the most energetic cosmic rays. High-energy gamma rays (>50   MeV photons) were finally discovered in the primary cosmic radiation by an MIT experiment carried on the OSO-3 satellite in 1967. Components of both galactic and extra-galactic origins were separately identified at intensities much less than 1% of

6216-757: The Rossi Cosmic Ray Group at the Massachusetts Institute of Technology . The experiment employed eleven scintillation detectors arranged within a circle 460 metres in diameter on the grounds of the Agassiz Station of the Harvard College Observatory . From that work, and from many other experiments carried out all over the world, the energy spectrum of the primary cosmic rays is now known to extend beyond 10  eV. A huge air shower experiment called

6327-410: The Solar System. Four allotropes (structural forms) of solid manganese are known, labeled α, β, γ and δ, and occurring at successively higher temperatures. All are metallic, stable at standard pressure, and have a cubic crystal lattice, but they vary widely in their atomic structures. Alpha manganese (α-Mn) is the equilibrium phase at room temperature. It has a body-centered cubic lattice and

6438-567: The alloys particularly useful in harsh automotive and industrial environments. Manganese oxide and sulfate are components of fertilizers. In the year 2000, an estimated 20,000 tons of these compounds were used in fertilizers in the US alone. A comparable amount of Mn compounds was also used in animal feeds. Methylcyclopentadienyl manganese tricarbonyl is an additive in some unleaded gasoline to boost octane rating and reduce engine knocking . Manganese(IV) oxide (manganese dioxide, MnO 2 )

6549-535: The arrival directions of the highest energy cosmic rays. Since the Galactic Center is in the deficit region, this anisotropy can be interpreted as evidence for the extragalactic origin of cosmic rays at the highest energies. This implies that there must be a transition energy from galactic to extragalactic sources, and there may be different types of cosmic-ray sources contributing to different energy ranges. Cosmic rays can be divided into two types: However,

6660-458: The assumption that radiation of very high penetrating power enters from above into our atmosphere." In 1913–1914, Werner Kolhörster confirmed Victor Hess's earlier results by measuring the increased ionization enthalpy rate at an altitude of 9 km. Hess received the Nobel Prize in Physics in 1936 for his discovery. Bruno Rossi wrote in 1964: In the late 1920s and early 1930s

6771-543: The bare nuclei of common atoms (stripped of their electron shells), and about 1% are solitary electrons (that is, one type of beta particle ). Of the nuclei, about 90% are simple protons (i.e., hydrogen nuclei); 9% are alpha particles , identical to helium nuclei; and 1% are the nuclei of heavier elements, called HZE ions . These fractions vary highly over the energy range of cosmic rays. A very small fraction are stable particles of antimatter , such as positrons or antiprotons . The precise nature of this remaining fraction

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6882-466: The choices of detectors. An example for the direct detection technique is a method based on nuclear tracks developed by Robert Fleischer, P. Buford Price , and Robert M. Walker for use in high-altitude balloons. In this method, sheets of clear plastic, like 0.25  mm Lexan polycarbonate, are stacked together and exposed directly to cosmic rays in space or high altitude. The nuclear charge causes chemical bond breaking or ionization in

6993-584: The damage they inflict on microelectronics and life outside the protection of an atmosphere and magnetic field, and scientifically, because the energies of the most energetic ultra-high-energy cosmic rays have been observed to approach 3 × 10 eV  (This is slightly greater than 21 million times the design energy of particles accelerated by the Large Hadron Collider , 14 teraelectronvolts [TeV] (1.4 × 10   eV ). ) One can show that such enormous energies might be achieved by means of

7104-481: The element, in the form of Spiegeleisen . Manganese comprises about 1000  ppm (0.1%) of the Earth's crust and is the 12th most abundant element. Soil contains 7–9000 ppm of manganese with an average of 440 ppm. The atmosphere contains 0.01 μg/m . Manganese occurs principally as pyrolusite ( MnO 2 ), braunite (Mn Mn 6 )SiO 12 ), psilomelane (Ba,H 2 O) 2 Mn 5 O 10 , and to

7215-460: The energy distribution of cosmic rays peaks at 300 megaelectronvolts [MeV] (4.8 × 10   J ). After the discovery of radioactivity by Henri Becquerel in 1896, it was generally believed that atmospheric electricity, ionization of the air , was caused only by radiation from radioactive elements in the ground or the radioactive gases or isotopes of radon they produce. Measurements of increasing ionization rates at increasing heights above

7326-417: The energy of cosmic ray flux in interstellar space is very comparable to that of other deep space energies: cosmic ray energy density averages about one electron-volt per cubic centimetre of interstellar space, or ≈1 eV/cm , which is comparable to the energy density of visible starlight at 0.3 eV/cm , the galactic magnetic field energy density (assumed 3 microgauss) which is ≈0.25 eV/cm , or

7437-403: The fine experiments of Professor Millikan and the even more far-reaching experiments of Professor Regener, we have now got for the first time, a curve of absorption of these radiations in water which we may safely rely upon". In the 1920s, the term cosmic ray was coined by Robert Millikan who made measurements of ionization due to cosmic rays from deep under water to high altitudes and around

7548-435: The flux of cosmic rays at Earth's surface. The following table of participial frequencies reach the planet and are inferred from lower-energy radiation reaching the ground. In the past, it was believed that the cosmic ray flux remained fairly constant over time. However, recent research suggests one-and-a-half- to two-fold millennium-timescale changes in the cosmic ray flux in the past forty thousand years. The magnitude of

7659-491: The form of ferrocene ( Fe(C 5 H 5 ) 2 ). When conducted under an atmosphere of carbon monoxide , reduction of Mn(II) salts gives dimanganese decacarbonyl Mn 2 (CO) 10 , an orange and volatile solid. The air-stability of this Mn(0) compound (and its many derivatives) reflects the powerful electron-acceptor properties of carbon monoxide. Many alkene complexes and alkyne complexes are derived from Mn 2 (CO) 10 . In Mn(CH 3 ) 2 (dmpe) 2 , Mn(II)

7770-465: The free element when it was isolated much later. Manganese dioxide, which is abundant in nature, has long been used as a pigment. The cave paintings in Gargas that are 30,000 to 24,000 years old are made from the mineral form of MnO 2 pigments. Manganese compounds were used by Egyptian and Roman glassmakers, either to add to, or remove, color from glass. Use as "glassmakers soap" continued through

7881-413: The globe. Millikan believed that his measurements proved that the primary cosmic rays were gamma rays; i.e., energetic photons. And he proposed a theory that they were produced in interstellar space as by-products of the fusion of hydrogen atoms into the heavier elements, and that secondary electrons were produced in the atmosphere by Compton scattering of gamma rays. In 1927, while sailing from Java to

7992-575: The ground during the decade from 1900 to 1910 could be explained as due to absorption of the ionizing radiation by the intervening air. In 1909, Theodor Wulf developed an electrometer , a device to measure the rate of ion production inside a hermetically sealed container, and used it to show higher levels of radiation at the top of the Eiffel Tower than at its base. However, his paper published in Physikalische Zeitschrift

8103-410: The high charge and heavy nature of HZE ions, their contribution to an astronaut's radiation dose in space is significant even though they are relatively scarce. This abundance difference is a result of the way in which secondary cosmic rays are formed. Carbon and oxygen nuclei collide with interstellar matter to form lithium , beryllium , and boron , an example of cosmic ray spallation . Spallation

8214-619: The incidence of gamma-ray bursts and cosmic rays, causing the authors to set upper limits as low as 3.4 × 10 ×  erg ·cm on the flux of 1 GeV – 1 TeV cosmic rays from gamma-ray bursts. In 2009, supernovae were said to have been "pinned down" as a source of cosmic rays, a discovery made by a group using data from the Very Large Telescope . This analysis, however, was disputed in 2011 with data from PAMELA , which revealed that "spectral shapes of [hydrogen and helium nuclei] are different and cannot be described well by

8325-469: The magnetic field of the solar wind through which cosmic rays propagate to Earth. This results in a modulation of the arriving fluxes at lower energies, as detected indirectly by the globally distributed neutron monitor network. Early speculation on the sources of cosmic rays included a 1934 proposal by Baade and Zwicky suggesting cosmic rays originated from supernovae. A 1948 proposal by Horace W. Babcock suggested that magnetic variable stars could be

8436-412: The manganese content reaches 4%, the embrittlement of the steel becomes a dominant feature. The embrittlement decreases at higher manganese concentrations and reaches an acceptable level at 8%. Steel containing 8 to 15% of manganese has a high tensile strength of up to 863 MPa. Steel with 12% manganese was discovered in 1882 by Robert Hadfield and is still known as Hadfield steel (mangalloy) . It

8547-503: The manganese ore to manganese oxide (MnO), which is a leachable form. The ore then travels through a grinding circuit to reduce the particle size of the ore to between 150 and 250 μm, increasing the surface area to aid leaching. The ore is then added to a leach tank of sulfuric acid and ferrous iron (Fe ) in a 1.6:1 ratio. The iron reacts with the manganese dioxide (MnO 2 ) to form iron hydroxide (FeO(OH)) and elemental manganese (Mn). This process yields approximately 92% recovery of

8658-460: The manganese. For further purification, the manganese can then be sent to an electrowinning facility. In 1972, the CIA 's Project Azorian , through billionaire Howard Hughes , commissioned the ship Hughes Glomar Explorer with the cover story of harvesting manganese nodules from the sea floor. That triggered a rush of activity to collect manganese nodules, which was not actually practical until

8769-633: The metal, but that is uncertain. By the mid-18th century, the Swedish chemist Carl Wilhelm Scheele used manganese dioxide to produce chlorine . First, hydrochloric acid , or a mixture of dilute sulfuric acid and sodium chloride was made to react with manganese dioxide, and later hydrochloric acid from the Leblanc process was used and the manganese dioxide was recycled by the Weldon process . The production of chlorine and hypochlorite bleaching agents

8880-573: The metals and organic compounds can then cause them to be oxidized while the Mn(III,IV) oxides are reduced to Mn (e.g., Cr to Cr(VI) and colorless hydroquinone to tea-colored quinone polymers). Manganese is essential to iron and steel production by virtue of its sulfur -fixing, deoxidizing , and alloying properties. Manganese has no satisfactory substitute in these applications in metallurgy. Steelmaking , including its ironmaking component, has accounted for most manganese demand, presently in

8991-418: The most abundant stable isotope, Mn, is electron capture and the primary mode in heavier isotopes is beta decay . Manganese also has three meta states . Manganese is part of the iron group of elements, which are thought to be synthesized in large stars shortly before the supernova explosion. Mn decays to Cr with a half-life of 3.7 million years. Because of its relatively short half-life, Mn

9102-524: The ocean from river inputs. Surface dMn concentrations can also be elevated biologically through photosynthesis and physically from coastal upwelling and wind-driven surface currents. Internal cycling such as photo-reduction from UV radiation can also elevate levels by speeding up the dissolution of Mn-oxides and oxidative scavenging, preventing Mn from sinking to deeper waters. Elevated levels at mid-depths can occur near mid-ocean ridges and hydrothermal vents. The hydrothermal vents release dMn enriched fluid into

9213-441: The oxides to the divalent cation. The Mn(III,IV) oxides exist as brownish-black stains and small nodules on sand, silt, and clay particles. These surface coatings on other soil particles have high surface area and carry negative charge. The charged sites can adsorb and retain various cations, especially heavy metals (e.g., Cr , Cu , Zn , and Pb ). In addition, the oxides can adsorb organic acids and other compounds. The adsorption of

9324-418: The particle cascade increases at lower elevations, reaching between 40% and 80% of the radiation at aircraft altitudes. Of secondary cosmic rays, the charged pions produced by primary cosmic rays in the atmosphere swiftly decay, emitting muons. Unlike pions, these muons do not interact strongly with matter, and can travel through the atmosphere to penetrate even below ground level. The rate of muons arriving at

9435-414: The plastic. At the top of the plastic stack the ionization is less, due to the high cosmic ray speed. As the cosmic ray speed decreases due to deceleration in the stack, the ionization increases along the path. The resulting plastic sheets are "etched" or slowly dissolved in warm caustic sodium hydroxide solution, that removes the surface material at a slow, known rate. The caustic sodium hydroxide dissolves

9546-479: The primary charged particles. Since then, numerous satellite gamma-ray observatories have mapped the gamma-ray sky. The most recent is the Fermi Observatory, which has produced a map showing a narrow band of gamma ray intensity produced in discrete and diffuse sources in our galaxy, and numerous point-like extra-galactic sources distributed over the celestial sphere. The solar cycle causes variations in

9657-576: The process has seen widespread use ever since. The invention of the Leclanché cell in 1866 and the subsequent improvement of batteries containing manganese dioxide as cathodic depolarizer increased the demand for manganese dioxide. Until the development of batteries with nickel–cadmium and lithium, most batteries contained manganese. The zinc–carbon battery and the alkaline battery normally use industrially produced manganese dioxide because naturally occurring manganese dioxide contains impurities. In

9768-494: The proportion of cosmic rays that they do produce is a question which cannot be answered without deeper investigation. To explain the actual process in supernovae and active galactic nuclei that accelerates the stripped atoms, physicists use shock front acceleration as a plausibility argument (see picture at right). In 2017, the Pierre Auger Collaboration published the observation of a weak anisotropy in

9879-400: The range of 85% to 90% of the total demand. Manganese is a key component of low-cost stainless steel . Often ferromanganese (usually about 80% manganese) is the intermediate in modern processes. Small amounts of manganese improve the workability of steel at high temperatures by forming a high-melting sulfide and preventing the formation of a liquid iron sulfide at the grain boundaries. If

9990-455: The rate of near-simultaneous discharges of two widely separated Geiger counters was larger than the expected accidental rate. In his report on the experiment, Rossi wrote "... it seems that once in a while the recording equipment is struck by very extensive showers of particles, which causes coincidences between the counters, even placed at large distances from one another." In 1937, Pierre Auger , unaware of Rossi's earlier report, detected

10101-501: The ratio of positrons to electrons begins to fall again. The absolute flux of positrons also begins to fall before 500 GeV, but peaks at energies far higher than electron energies, which peak about 10 GeV. These results on interpretation have been suggested to be due to positron production in annihilation events of massive dark matter particles. Cosmic ray antiprotons also have a much higher average energy than their normal-matter counterparts (protons). They arrive at Earth with

10212-481: The regions of the Magnetes (either Magnesia , located within modern Greece, or Magnesia ad Sipylum , located within modern Turkey). They were both called magnes from their place of origin, but were considered to differ in sex. The male magnes attracted iron, and was the iron ore now known as lodestone or magnetite , and which probably gave us the term magnet . The female magnes ore did not attract iron, but

10323-415: The same basic reaction, but a different electrolyte mixture. In 2002, more than 230,000 tons of manganese dioxide was used for this purpose. Copper alloys of manganese, such as Manganin , are commonly found in metal element shunt resistors used for measuring relatively large amounts of current. These alloys have very low temperature coefficient of resistance and are resistant to sulfur. This makes

10434-441: The same phenomenon and investigated it in some detail. He concluded that high-energy primary cosmic-ray particles interact with air nuclei high in the atmosphere, initiating a cascade of secondary interactions that ultimately yield a shower of electrons, and photons that reach ground level. Soviet physicist Sergei Vernov was the first to use radiosondes to perform cosmic ray readings with an instrument carried to high altitude by

10545-440: The secondary radiation produced in the atmosphere is primarily electrons, photons and muons . In 1948, observations with nuclear emulsions carried by balloons to near the top of the atmosphere showed that approximately 10% of the primaries are helium nuclei (alpha particles) and 1% are nuclei of heavier elements such as carbon, iron, and lead. During a test of his equipment for measuring the east–west effect, Rossi observed that

10656-461: The strength of the solar wind is not constant, and hence it has been observed that cosmic ray flux is correlated with solar activity. In addition, the Earth's magnetic field acts to deflect cosmic rays from its surface, giving rise to the observation that the flux is apparently dependent on latitude , longitude , and azimuth angle . The combined effects of all of the factors mentioned contribute to

10767-439: The surface of the Earth is such that about one per second passes through a volume the size of a person's head. Together with natural local radioactivity, these muons are a significant cause of the ground level atmospheric ionisation that first attracted the attention of scientists, leading to the eventual discovery of the primary cosmic rays arriving from beyond our atmosphere. Cosmic rays attract great interest practically, due to

10878-531: The surface of the Earth. Some high-energy muons even penetrate for some distance into shallow mines, and most neutrinos traverse the Earth without further interaction. Others decay into photons, subsequently producing electromagnetic cascades. Hence, next to photons, electrons and positrons usually dominate in air showers. These particles as well as muons can be easily detected by many types of particle detectors, such as cloud chambers , bubble chambers , water-Cherenkov , or scintillation detectors. The observation of

10989-495: The technique of self-recording electroscopes carried by balloons into the highest layers of the atmosphere or sunk to great depths under water was brought to an unprecedented degree of perfection by the German physicist Erich Regener and his group. To these scientists we owe some of the most accurate measurements ever made of cosmic-ray ionization as a function of altitude and depth. Ernest Rutherford stated in 1931 that "thanks to

11100-414: The term "cosmic ray" is often used to refer to only the extrasolar flux. Cosmic rays originate as primary cosmic rays, which are those originally produced in various astrophysical processes. Primary cosmic rays are composed mainly of protons and alpha particles (99%), with a small amount of heavier nuclei (≈1%) and an extremely minute proportion of positrons and antiprotons. Secondary cosmic rays, caused by

11211-437: The term "rays" was still consistent with then known particles such as cathode rays , canal rays , alpha rays , and beta rays . Meanwhile "cosmic" ray photons , which are quanta of electromagnetic radiation (and so have no intrinsic mass) are known by their common names, such as gamma rays or X-rays , depending on their photon energy . Of primary cosmic rays, which originate outside of Earth's atmosphere, about 99% are

11322-452: The upper atmosphere is dependent on the solar wind , the Earth's magnetic field , and the energy of the cosmic rays. At distances of ≈94  AU from the Sun, the solar wind undergoes a transition, called the termination shock , from supersonic to subsonic speeds. The region between the termination shock and the heliopause acts as a barrier to cosmic rays, decreasing the flux at lower energies (≤ 1 GeV) by about 90%. However,

11433-443: The upper atmosphere to produce particles observed at the ground level. Bhabha and Heitler explained the cosmic ray shower formation by the cascade production of gamma rays and positive and negative electron pairs. Measurements of the energy and arrival directions of the ultra-high-energy primary cosmic rays by the techniques of density sampling and fast timing of extensive air showers were first carried out in 1954 by members of

11544-462: The very highest-energy primary cosmic rays. The results are expected to have important implications for particle physics and cosmology, due to a theoretical Greisen–Zatsepin–Kuzmin limit to the energies of cosmic rays from long distances (about 160 million light years) which occurs above 10  eV because of interactions with the remnant photons from the Big Bang origin of the universe. Currently

11655-589: The water. The dMn can then travel up to 4,000 km due to the microbial capsules present, preventing exchange with particles, lowing the sinking rates. Dissolved Mn concentrations are even higher when oxygen levels are low. Overall, dMn concentrations are normally higher in coastal regions and decrease when moving offshore. Manganese occurs in soils in three oxidation states: the divalent cation, Mn and as brownish-black oxides and hydroxides containing Mn (III,IV), such as MnOOH and MnO 2 . Soil pH and oxidation-reduction conditions affect which of these three forms of Mn

11766-482: Was a large consumer of manganese ores. Scheele and others were aware that pyrolusite (mineral form of manganese dioxide) contained a new element. Johan Gottlieb Gahn isolated an impure sample of manganese metal in 1774, which he did by reducing the dioxide with carbon . The manganese content of some iron ores used in Greece led to speculations that steel produced from that ore contains additional manganese, making

11877-575: Was flown into space aboard the Space Shuttle Discovery on STS-91 in June 1998. By not detecting any antihelium at all, the AMS-01 established an upper limit of 1.1 × 10 for the antihelium to helium flux ratio. When cosmic rays enter the Earth's atmosphere , they collide with atoms and molecules , mainly oxygen and nitrogen. The interaction produces a cascade of lighter particles,

11988-467: Was not widely accepted. In 1911, Domenico Pacini observed simultaneous variations of the rate of ionization over a lake, over the sea, and at a depth of 3 metres from the surface. Pacini concluded from the decrease of radioactivity underwater that a certain part of the ionization must be due to sources other than the radioactivity of the Earth. In 1912, Victor Hess carried three enhanced-accuracy Wulf electrometers to an altitude of 5,300 metres in

12099-572: Was used for British military steel helmets and later by the U.S. military. Manganese is used in production of alloys with aluminium. Aluminium with roughly 1.5% manganese has increased resistance to corrosion through grains that absorb impurities which would lead to galvanic corrosion . The corrosion-resistant aluminium alloys 3004 and 3104 (0.8 to 1.5% manganese) are used for most beverage cans . Before 2000, more than 1.6 million tonnes of those alloys were used; at 1% manganese, this consumed 16,000 tonnes of manganese. Manganese(IV) oxide

12210-414: Was used in the original type of dry cell battery as an electron acceptor from zinc, and is the blackish material in carbon–zinc type flashlight cells. The manganese dioxide is reduced to the manganese oxide-hydroxide MnO(OH) during discharging, preventing the formation of hydrogen at the anode of the battery. The same material also functions in newer alkaline batteries (usually battery cells), which use

12321-438: Was used to decolorize glass. This female magnes was later called magnesia , known now in modern times as pyrolusite or manganese dioxide . Neither this mineral nor elemental manganese is magnetic. In the 16th century, manganese dioxide was called manganesum (note the two Ns instead of one) by glassmakers, possibly as a corruption and concatenation of two words, since alchemists and glassmakers eventually had to differentiate

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