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manganese

 
(măng'gə-nēz', -nēs') pronunciation
n. (Symbol Mn)
A gray-white or silvery brittle metallic element, occurring in several allotropic forms, found worldwide, especially in the ores pyrolusite and rhodochrosite and in nodules on the ocean floor. It is alloyed with steel to increase strength, hardness, wear resistance, and other properties and with other metals to form highly ferromagnetic materials. Atomic number 25; atomic weight 54.9380; melting point 1,244°C; boiling point 1,962°C; specific gravity 7.21 to 7.44; valence 1, 2, 3, 4, 6, 7.

[French manganèse, from Italian manganese, from Medieval Latin magnēsia, mineral ingredient of the philosophers' stone. See magnesia.]

manganesian man'ga·ne'sian (-nē'zhən, -shən) adj.

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Metallic chemical element, one of the transition elements, chemical symbol Mn, atomic number 25. It is a silvery white, hard, brittle metal, widely distributed in Earth's crust in combination with other elements. Nodules rich in manganese occur in huge quantities on the seafloor, but no economical way to mine them has been devised. More than 95% of the manganese produced is used in iron and steel alloys and much of the rest in nonferrous aluminum and magnesium alloys to improve their corrosion resistance and mechanical properties. Manganese compounds, in which it has various valences, are used in fertilizers and textile printing and as reagents and raw materials. Potassium permanganate is used for disinfecting, deodorizing, and bleaching and as a reagent in analysis. Manganese is essential to plants for growth and to higher animals to promote the action of many enzymes.

For more information on manganese, visit Britannica.com.

A metallic element, Mn, atomic number 25, and atomic weight 54.9380 g/mole. Manganese is one of the transition elements of the first long period of the periodic table, falling between chromium and iron. The principal properties of manganese are given in the table. It is the twelfth most abundant element in the Earth's crust (approximately 0.1%) and occurs naturally in several forms, primarily as the silicate (MnSiO3) but also as the carbonate (MnCO3) and a variety of oxides, including pyrolusite (MnO2) and hausmannite (Mn3O4). Weathering of land deposits has led to large amounts of the oxide being washed out to sea, where they have aggregated into the so-called manganese nodules containing 15–30% Mn. Vast deposits, estimated at over 1012 metric tons, have been detected on the seabed, and a further 107 metric tons is deposited every year. The nodules also contain smaller amounts of the oxides of other metals such as iron (Fe), cobalt (Co), nickel (Ni), and copper (Cu). The economic importance of the nodules as a source of these important metals is enormous. See also Periodic table.

Properties of manganese

Property

Value

Atomic number

25

Atomic weight, g/mole

54.9380

Naturally occurring isotope

55Mn (100%)

Electronic configuration

[Ar]3d54s2

Electronegativity

1.5

Metal radius, picometers

127

Melting point, °C (°F)

1244 ± 3 (2271 ± 5.4)

Boiling point. °C (°F)

1962 (3563)

Density (25 °C or 77°F), g/cm3 (oz/in.3)

7.43 (4.30)

Electrical resistivity, ohm·cm

185 × 10−6

Manganese is more electropositive than its near neighbors in the periodic table, and consequently more reactive. The bulk metal undergoes only surface oxidation when exposed to atmospheric oxygen, but finely divided metal is pyrophoric.

Manganese is a trace element essential to a variety of living systems, including bacteria, plants, and animals. In contrast to iron (Fe), its neighbor in the periodic table, the exact function of the manganese in many of these systems was determined only recently. The manganese superoxide dismutases have been isolated from bacteria, plants, and animals, and are relatively small enzymes with molecular weights of approximately 20,000. The function of the enzyme is believed to be protection of living tissue from the harmful effects of the superoxide ion (O2), a radical formed from partial reduction of O2 in the cells of respiring (O2-utilizing) cells.

The most important biological role yet recognized for manganese is in the enzyme responsible for photosynthetic water oxidation to oxygen in plants and certain photosynthetic bacteria. This reaction represents the source of oxygen gas on the Earth and is therefore responsible for the development of the most common forms of life.

All steels contain some manganese, the major advantage being an increase in hardness, although it also serves as a scavenger of oxygen and sulfur impurities that would induce defects and consequent brittleness in the steel. Manganese even has some use in the electronics industry, where manganese dioxide, either natural or synthetic, is employed to produce manganese compounds possessing high electrical resistivity; among other applications, these are utilized as components in every television set. See also Electrolysis; Transition elements.


An essential trace mineral which functions as the prosthetic group in a number of enzymes. Dietary deficiency has not been reported in human beings; in experimental animals manganese deficiency leads to impaired synthesis of mucopolysaccharides. Requirements are not known; US/Canadian adequate intake is 2.3 mg for men and 1.8 for women.

A metallic element, essential in the diet but required in very small amounts. It is a component of a number of enzyme systems, including those involved in the synthesis of cartilage. Good sources of manganese include nuts, legumes, wholegrains, leafy vegetables, and fruit. Deficiency is unknown in humans, therefore there are no recommended intakes.

A metallic element used as an alloying element in steel as a hardener and deoxidizer; also used as an alloying element in other metals such as copper to introduce high mechanical damping.


An essential trace element required for the efficient functioning of a number of enzyme systems. Manganese deficiency causes tremors and convulsions. Good sources include nuts, legumes, wholegrains, leafy green vegetables, and fruit.


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What is Manganese?

Manganese (Mn) is a mineral necessary in very tiny (trace) amounts for human health. In large quantities, manganese is poisonous. Manganese is used in some enzyme reactions and for the proper development of bones and cartilage. Humans must meet their needs for manganese from their diet. Manganese is found mainly in plants and in small quantities in some drinking water. What is the Purpose of Manganese?

Researchers understand less about how manganese functions in the body than they do about many other minerals. Studies have shown that manganese is necessary for proper development of healthy bones and cartilage in animals. It is highly likely that manganese plays the same role in the development of human bones and connective tissue, although manganese deficiency is so rare in humans (and putting people on a prolonged manganese-free diet would be an unethical experiment) that this has not been proven experimentally.

Manganese is also necessary for the formation of an antioxidant enzyme in cellular mitochondria. Mitochondria, sometimes called the cell’s power plant, are organelles that use large amounts of oxygen to produce energy. The production of energy by the mitochondria results in the formation of free radicals. Free radicals are molecules that cause damage by reacting with fats and proteins in cell membranes and in genetic material. This process is called oxidation. Antioxi-dants are compounds that attach themselves to free radicals so that it is impossible for free radicals to react with, or oxidize, other molecules. In this way, antiox-idants protect cells from damage. Although manganese is not by itself an antioxidant, it is a necessary part of the enzyme reaction that neutralizes free radicals produced by mitochondria. Manganese is also needed in some enzyme reactions that allow the body to process the use of amino acids, cholesterol, and carbohydrates in the body.

Manganese

AgeRecommended Dietary Allowance (mg)Tolerable Upper Intake Level (mg)
Children 0–6 mos.0.3 (AI)Not established
Children 7–12 mos.0.6 (AI)Not established
Children 1–3 yrs.1.22
Children 4–8 yrs.1.53
Boys 9–13 yrs.1.96
Girls 9–13 yrs.1.66
Boys 14–18 yrs.2.29
Girls 14–18 yrs.1.69
Men 19≤ yrs.2.311
Women 19≤ yrs.1.811
Pregnant women2.011
Breastfeeding women2.611
FoodManganese (mg)
Tea, green, 1 cup1.58
Pineapple, raw, ½ cup1.28
Pecans, 1 oz.1.12
Cereal, raisin bran, ½ cup.94
Brown rice, cooked, ½ cup.88
Spinach, cooked, ½ cup.84
Tea, black, 1 cup.77
Almonds, 1 oz..74
Bread, whole wheat, 1 slice.65
Peanuts, 1 oz..59
Sweet potato, mashed, ½ cup.55
Beans, navy, cooked, ½ cup.51
Beans, lima, cooked, ½ cup.48
Beans, pinto, cooked, ½ cup.48
AI = Adequate Intake 
mg = milligram 
Columbia Encyclopedia:

manganese

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manganese (măng'gənēs, măn'-) [Lat.,=magnet], metallic chemical element; symbol Mn; at. no. 25; at. wt. 54.93805; m.p. about 1,244°C; b.p. about 1,962°C; sp. gr. 7.2 to 7.45, depending on form; valence principally +2, +4, or +7.

Manganese is a pinkish-gray, chemically active metal. It is the first element in Group 7 of the periodic table. It resembles iron but is harder and more brittle. The metal exhibits allotropy; it has four different forms with varying physical properties. It can be highly polished. Manganese tarnishes in moist air and oxidizes when heated to form an oxide, Mn3O4. It slowly displaces hydrogen from water. It reacts readily with hydrochloric and sulfuric acids and with the halogens.

In compounds, manganese assumes a number of different oxidation states. It is easily raised to the +2 state, for example, by reaction with hydrochloric acid to form manganous chloride, MnCl2. Manganese is also found in the +3 (manganic) state, but this state is unstable and usually reverts to the +2 state. Both manganous and manganic ions form acidic solutions. Manganese is found in the +4 state largely in manganese dioxide, MnO2 ; the +4 oxidation state is amphoteric, i.e., in the +4 state manganese can either donate or accept electrons in chemical reactions. Manganese also exists in +6 and +7 states; the +6 state is found in the manganate ion (MnO4−−) and the +7 state in the permanganate ion (MnO4). These ions are stable in basic solutions. There is also evidence for a +1 state (in a complex cyanide) and for an unstable +5 state (in basic solutions). Manganese is found in abundance in nature.

Pyrolusite (MnO2) is the major ore. Manganese ores are produced principally in the countries of the former Soviet Union, India, the Union of South Africa, Ghana, and Morocco, and to a lesser extent in the United States. The metal is prepared commercially by reduction of its ores with aluminum or, with high purity, by electrolysis of a manganese sulfate solution. Manganese is very important in the steel industry, where it is used as a deoxidizing and desulfurizing agent; no substitute has been found. It is also used in large amounts to toughen and harden steel without making it brittle; it is usually added as ferromanganese. Any steel having between 10% and 15% manganese is known as manganese steel, although almost all steel contains some manganese. Manganese is widely used in making alloys. Manganese bronze and manganese brass are alloys containing manganese, copper, tin, zinc, and small amounts of other metals in varying proportions. Certain alloys containing manganese, aluminum, antimony, and small amounts of copper are highly magnetic.

Compounds of manganese are widely used in industry. Manganese dioxide is used as a drying agent; it catalyzes the oxidation of oils in paints and varnishes. It is also used in the dry cell and to remove the green color caused by iron impurities in glass. Potassium permanganate (KMnO4) is a powerful oxidizing agent used industrially for bleaching and in chemistry as an analytical reagent. Other compounds find use in glassmaking, as pigments, and as fertilizers. Manganese is needed as a nutrient in small amounts by many plants and animals and by humans. The purple color of amethyst is due to manganese. The element was first isolated in 1774 by J. G. Gahn, although its existence was previously recognized by T. O. Bergman and by K. W. Scheele.



symbol: Mn; a ferromagnetic, metallic transition element of group 7 of the IUPAC periodic table; atomic number 25; relative atomic mass 54.938. There is one stable nuclide of mass number 55. Manganese is widely distributed and abundant in the Earth's crust and is an essential component of all living material. It forms manganese(II) (manganous) and less stable manganese(III) (manganic) compounds, including ionic compounds, and complexes; it can also exist in higher oxidation states. Mn2+ ions act as activators of various enzymes. A number of artificial radioactive isotopes are known.

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A chemical element, atomic number 25, atomic weight 54.938, symbol Mn. See Table 6. Its salts occur in the body tissue in very small amounts and serve as activators of liver arginase and other enzymes.

  • m. nutritional deficiency — in cattle, sheep and pigs is thought to cause infertility and skeletal deformities, including enlarged joints, pain, knuckling at the fetlocks and twisting of the legs. It is a rare deficiency in dogs and cats.

n
Mn

A common metallic element found in trace amounts in tissues of the body, where it aids in the function of various enzymes. Its atomic number is 25 and its atomic weight is 54.9380.

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chromiummanganeseiron
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Mn

Tc
Appearance
silvery metallic
A rough fragment of lustrous silvery metal
General properties
Name, symbol, number manganese, Mn, 25
Pronunciation /ˈmæŋɡənz/ mang-gən-neez
Element category transition metal
Group, period, block 74, d
Standard atomic weight 54.938045(5)
Electron configuration [Ar] 4s2 3d5
Electrons per shell 2, 8, 13, 2 (Image)
Physical properties
Phase solid
Density (near r.t.) 7.21 g·cm−3
Liquid density at m.p. 5.95 g·cm−3
Melting point 1519 K, 1246 °C, 2275 °F
Boiling point 2334 K, 2061 °C, 3742 °F
Heat of fusion 12.91 kJ·mol−1
Heat of vaporization 221 kJ·mol−1
Molar heat capacity 26.32 J·mol−1·K−1
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1228 1347 1493 1691 1955 2333
Atomic properties
Oxidation states 7, 6, 5, 4, 3, 2, 1, -1, -2, -3
(oxides: acidic, basic or amphoteric
depending on the oxidation state)
Electronegativity 1.55 (Pauling scale)
Ionization energies
(more)
1st: 717.3 kJ·mol−1
2nd: 1509.0 kJ·mol−1
3rd: 3248 kJ·mol−1
Atomic radius 127 pm
Covalent radius 139±5 (low spin), 161±8 (high spin) pm
Miscellanea
Crystal structure body-centered cubic
Magnetic ordering paramagnetic
Electrical resistivity (20 °C) 1.44 µΩ·m
Thermal conductivity 7.81 W·m−1·K−1
Thermal expansion (25 °C) 21.7 µm·m−1·K−1
Speed of sound (thin rod) (20 °C) 5150 m·s−1
Young's modulus 198 GPa
Bulk modulus 120 GPa
Mohs hardness 6.0
Brinell hardness 196 MPa
CAS registry number 7439-96-5
Most stable isotopes
Main article: Isotopes of manganese
iso NA half-life DM DE (MeV) DP
52Mn syn 5.591 d ε - 52Cr
β+ 0.575 52Cr
γ 0.7, 0.9, 1.4 -
53Mn trace 3.74 ×106 y ε - 53Cr
54Mn syn 312.3 d ε 1.377 54Cr
γ 0.834 -
55Mn 100% 55Mn is stable with 30 neutrons
· r

Manganese (play /ˈmæŋɡənz/ mang-gə-neez) is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature (often in combination with iron), and in many minerals. As a free element, manganese is a metal with important industrial metal alloy uses, particularly in stainless steels.

Historically, manganese is named for various black minerals (such as pyrolusite) from the same region of Magnesia in Greece which gave names to similar-sounding magnesium, Mg (see magnesia ) and magnetite, an ore of the element iron, Fe. By the mid-18th century, Swedish chemist Carl Wilhelm Scheele had used pyrolusite to produce chlorine. Scheele and others were aware that pyrolusite (now known to be manganese dioxide) contained a new element, but they were not able to isolate it. Johan Gottlieb Gahn was the first to isolate an impure sample of manganese metal in 1774, by reducing the dioxide with carbon.

Manganese phosphating is used as a treatment for rust and corrosion prevention on steel. Depending on their oxidation state, manganese ions have various colors and are used industrially as pigments. The permanganates of alkali and alkaline earth metals are powerful oxidizers. Manganese dioxide is used as the cathode (electron acceptor) material in standard and alkaline disposable dry cells and batteries.

Manganese(II) ions function as cofactors for a large variety of enzymes with many functions. Manganese enzymes are particularly essential in detoxification of superoxide free radicals in organisms that must deal with elemental oxygen. Manganese also functions in the oxygen-evolving complex of photosynthetic plants. The element is a required trace mineral for all known living organisms. In larger amounts, and apparently with far greater activity by inhalation, manganese can cause a poisoning syndrome in mammals, with neurological damage which is sometimes irreversible.

Contents

Characteristics

Physical properties

Manganese electrolytic made chips and 1cm3 cube

Manganese is a silvery-gray metal resembling iron. It is hard and very brittle, difficult to fuse, but easy to oxidize.[1] Manganese metal and its common ions are paramagnetic.[2]

Isotopes

Naturally occurring manganese is composed of one stable isotope, 55Mn. Eighteen radioisotopes have been characterized, with the most stable being 53Mn with a half-life of 3.7 million years, 54Mn with a half-life of 312.3 days, and 52Mn with a half-life of 5.591 days. All of the remaining radioactive isotopes have half-lives that are less than three hours and the majority of these have half-lives that are less than one minute. This element also has three meta states.[3]

Manganese is part of the iron group of elements, which are thought to be synthesized in large stars shortly before the supernova explosion. 53Mn decays to 53Cr with a half-life of 3.7 million years. Because of its relatively short half-life, 53Mn occurs only in tiny amounts due to the action of cosmic rays on iron in rocks.[4] 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 26Al and 107Pd for the early history of the solar system. Variations in 53Cr/52Cr and Mn/Cr ratios from several meteorites indicate an initial 53Mn/55Mn ratio that suggests Mn–Cr isotopic composition must result from in situ decay of 53Mn in differentiated planetary bodies. Hence 53Mn provides additional evidence for nucleosynthetic processes immediately before coalescence of the solar system.[3]

The isotopes of manganese range in atomic weight from 46 u (46Mn) to 65 u (65Mn). The primary decay mode before the most abundant stable isotope, 55Mn, is electron capture and the primary mode after is beta decay.[3]

Chemical properties

The most common oxidation states of manganese are +2, +3, +4, +6 and +7, though oxidation states from −3 to +7 are observed. Mn2+ often competes with Mg2+ in biological systems. Manganese compounds where manganese is in oxidation state +7, which are restricted to the unstable oxide Mn2O7 and compounds of the intensely purple permanganate anion MnO4, are powerful oxidizing agents.[1] Compounds with oxidation states +5 (blue) and +6 (green) are strong oxidizing agents and are vulnerable to disproportionation.

Manganese chloride crystals - the pale pink color of Mn (II) salts is due to a spin-forbidden 3d transition, which is rare.
Aqueous solution of KMnO4 illustrating the deep purple of Mn(VII) as it occurs in permanganate

The most stable oxidation state for manganese is +2, which has a pale pink color, and many manganese(II) compounds are known, such as manganese(II) sulfate (MnSO4) and manganese(II) chloride (MnCl2). This oxidation state is also seen in the mineral rhodochrosite, (manganese(II) carbonate). The +2 oxidation state is the state used in living organisms for essential functions; other states are toxic for the human body. The +2 oxidation of Mn results from removal of the two 4s electrons, leaving a "high spin" ion in which all five of the 3d orbitals contain a single electron. Absorption of visible light by this ion is accomplished only by a spin-forbidden transition in which one of the d electrons must pair with another, to give the atom a change in spin of two units. The unlikeliness of such a transition is seen in the uniformly pale and almost colorless nature of Mn(II) compounds relative to other oxidation states of manganese.[5]

Oxidation states of manganese[6]
0 Mn2(CO)10
+1 K5[Mn(CN)6NO]
+2 MnCl2
+3 MnF3
+4 MnO2
+5 K3MnO4
+6 K2MnO4
+7 KMnO4
Common oxidation states are in bold.

The +3 oxidation state is known in compounds like manganese(III) acetate, but these are quite powerful oxidizing agents and also prone to disproportionation in solution to manganese(II) and manganese(IV). Solid compounds of manganese(III) are characterized by their preference for distorted octahedral coordination due to the Jahn-Teller effect and its strong purple-red color.

The oxidation state 5+ can be obtained if manganese dioxide is dissolved in molten sodium nitrite.[7] Manganate (VI) salts can also be produced by dissolving Mn compounds, such as manganese dioxide, in molten alkali while exposed to air.

Permanganate (+7 oxidation state) compounds are purple, and can give glass a violet color. Potassium permanganate, sodium permanganate and barium permanganate are all potent oxidizers. Potassium permanganate, also called Condy's crystals, is a commonly used laboratory reagent because of its oxidizing properties and finds use 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.[8]

History

The origin of the name manganese is complex. In ancient times, two black minerals from Magnesia in what is now modern Greece, were both called magnes from their place of origin, but were thought to differ in gender. The male magnes attracted iron, and was the iron ore we now know as lodestone or magnetite, and which probably gave us the term magnet. The female magnes ore did not attract iron, but was used to decolorize glass. This feminine magnes was later called magnesia, known now in modern times as pyrolusite or manganese dioxide. Neither this mineral nor manganese itself is magnetic. In the 16th century, manganese dioxide was called manganesum (note the two n's instead of one) by glassmakers, possibly as a corruption and concatenation of two words, since alchemists and glassmakers eventually had to differentiate a magnesia negra (the black ore) from magnesia alba (a white ore, also from Magnesia, also useful in glassmaking). Michele Mercati called magnesia negra 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 that free element, when it was eventually isolated, much later.[9]

A drawing of a left-facing bull, in black, on a cave wall
Some of the cave painting in Lascaux, France use manganese-based pigments.[10]

Several oxides of manganese, for example manganese dioxide, are abundant in nature, and owing to their color, these oxides have been used as since the Stone Age. The cave paintings in Gargas contain manganese as pigments and these cave paintings are 30,000 to 24,000 years old.[11]

Manganese compounds were used by Egyptian and Roman glassmakers, to either remove color from glass or add color to it.[12] The use as "glassmakers soap" continued through the Middle Ages until modern times and is evident in 14th-century glass from Venice.[13]

Credit for first isolating manganese is usually given to Johan Gottlieb Gahn.

Because of the use in glassmaking, manganese dioxide was available to alchemists, the first chemists, and was used for experiments. Ignatius Gottfried Kaim (1770) and Johann Glauber (17th century) discovered that manganese dioxide could be converted to permanganate, a useful laboratory reagent.[14] 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, 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 containing bleaching agents was a large consumer of manganese ores.

Scheele and other chemists were aware that manganese dioxide contained a new element, but they were not able to isolate it. Johan Gottlieb Gahn was the first to isolate an impure sample of manganese metal in 1774, by reducing the dioxide with carbon.

The manganese content of some iron ores used in Greece led to the speculations that the steel produced from that ore contains inadvertent amounts of manganese, making the Spartan steel exceptionally hard.[15] Around the beginning of the 19th century, manganese was used in steelmaking and several patents were granted. In 1816, it was noted that adding manganese to iron made it harder, without making it any more brittle. In 1837, British academic James Couper noted an association between heavy exposures to manganese in mines with a form of Parkinson's disease.[16] In 1912, manganese phosphating electrochemical conversion coatings for protecting firearms against rust and corrosion were patented in the United States, and have seen widespread use ever since.[17]

The invention of the Leclanché cell in 1866 and the subsequent improvement of the batteries containing manganese dioxide as cathodic depolarizer increased the demand of manganese dioxide. Until the introduction of the nickel-cadmium battery and lithium-containing batteries, most batteries contained manganese. The zinc-carbon battery and the alkaline battery normally use industrially produced manganese dioxide, because natural occurring manganese dioxide contains impurities. In the 20th century, manganese dioxide has seen wide commercial use as the chief cathodic material for commercial disposable dry cells and dry batteries of both the standard (zinc-carbon) and alkaline types.[18]

Occurrence and production

Manganese makes up about 1000 ppm (0.1%) of the Earth's crust, making it the 12th most abundant element there.[19] Soil contains 7–9000 ppm of manganese with an average of 440 ppm.[19] Seawater has only 10 ppm manganese and the atmosphere contains 0.01 µg/m3.[19] Manganese occurs principally as pyrolusite (MnO2), braunite, (Mn2+Mn3+6)(SiO12),[20] psilomelane (Ba,H2O)2Mn5O10, and to a lesser extent as rhodochrosite (MnCO3).

ManganeseOreUSGOV.jpg
Mineraly.sk - psilomelan.jpg
Spiegeleisen.jpg
Dendrites01.jpg
The Searchlight Rhodochrosite Crystal.jpg
Manganese ore Psilomelane (manganese ore) Spiegeleisen is an iron alloy with a manganese content of approximately 15% Manganese oxide dendrites on limestone from Solnhofen, Germany—a kind of pseudofossil. Scale is in mm Mineral rhodochrosite (manganese(II) carbonate) in which the deep red color is due to impurities, not manganese
Percentage of manganese output in 2006 by countries[21]

The most important manganese ore is pyrolusite (MnO2). Other economically important manganese ores usually show a close spatial relation to the iron ores.[1] Land-based resources are large but irregularly distributed. About 80% of the known world manganese resources are found in South Africa; other important manganese deposits are in Ukraine, Australia, India, China, Gabon and Brazil.[21] In 1978, 500 billion tons of manganese nodules were estimated to exist on the ocean floor.[22] Attempts to find economically viable methods of harvesting manganese nodules were abandoned in the 1970s.[23]

Manganese is mined in South Africa, Australia, China, Brazil, Gabon, Ukraine, India and Ghana and Kazakhstan. US Import Sources (1998–2001): Manganese ore: Gabon, 70%; South Africa, 10%; Australia, 9%; Mexico, 5%; and other, 6%. Ferromanganese: South Africa, 47%; France, 22%; Mexico, 8%; Australia, 8%; and other, 15%. Manganese contained in all manganese imports: South Africa, 31%; Gabon, 21%; Australia, 13%; Mexico, 8%; and other, 27%.[21][24]

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.[25] The resulting ferromanganese has a manganese content of 30 to 80%.[1] Pure manganese used for the production of noniron alloys is produced by leaching manganese ore with sulfuric acid and a subsequent electrowinning process.[26]

Applications

Manganese has no satisfactory substitute in its major applications, which are related to metallurgical alloy use.[21] In minor applications, (e.g., manganese phosphating), zinc and sometimes vanadium are viable substitutes. In disposable battery manufacture, standard and alkaline cells using manganese will be generally replaced in the future with lithium battery technology.

Steel

US Marine Corps steel helmet

Manganese is essential to iron and steel production by virtue of its sulfur-fixing, deoxidizing, and alloying properties. Steelmaking,[27] including its ironmaking component, has accounted for most manganese demand, presently in the range of 85% to 90% of the total demand.[26] Among a variety of other uses, manganese is a key component of low-cost stainless steel formulations.[24][28]

Small amounts of manganese improve the workability of steel at high temperatures, because it forms a high melting sulfide and therefore prevents the formation of a liquid iron sulfide at the grain boundaries. If 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 can have a high tensile strength of up to 863 MPa.[29][30] Steel with 12% manganese was used for the British steel helmets. This steel composition was discovered in 1882 by Robert Hadfield and is still known as Hadfield steel.[31]

Aluminium alloys

The second large application for manganese is as alloying agent for aluminium. Aluminium with a manganese content of roughly 1.5% has an increased resistance against corrosion due to the formation of grains absorbing impurities which would lead to galvanic corrosion.[32] The corrosion-resistant aluminium alloys 3004 and 3104 with a manganese content of 0.8 to 1.5% are the alloys used for most of the beverage cans.[33] Before year 2000, in excess of 1.6 million tonnes have been used of those alloys; with a content of 1% manganese, this amount would need 16,000 tonnes of manganese.[33]

Other uses

World War II-time nickel (1942-5 identified by mint mark P,D or S above dome) made from a 56% copper-35% silver-9% manganese alloy

Methylcyclopentadienyl manganese tricarbonyl is used as an additive in unleaded gasoline to boost octane rating and reduce engine knocking. The manganese in this unusual organometallic compound is in the +1 oxidation state.[34]

Manganese(IV) oxide (manganese dioxide, MnO2) is used as a reagent in organic chemistry for the oxidation of benzylic alcohols (i.e. adjacent to an aromatic ring). Manganese dioxide has been used since antiquity to oxidatively neutralize the greenish tinge in glass caused by trace amounts of iron contamination.[13] MnO2 is also used in the manufacture of oxygen and chlorine, and in drying black paints. In some preparations, it is a brown pigment that can be used to make paint and is a constituent of natural umber.

Manganese(IV) oxide was used in the original type of dry cell battery as an electron acceptor from zinc, and is the blackish material found when opening 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.[35]

MnO2 + H2O + e → MnO(OH) + OH

The same material also functions in newer alkaline batteries (usually battery cells), which use the same basic reaction, but a different electrolyte mixture. In 2002, more than 230,000 tons of manganese dioxide was used for this purpose.[18][35]

The metal is very occasionally used in coins; until 2000, the only United States coin to use manganese was the "wartime" nickel from 1942–1945.[36] An alloy of 75% copper and 25% nickel was traditionally used for the production of nickel coins. However, because of shortage of nickel metal during the war, it was substituted by more available silver and manganese, thus resulting in an alloy of 56% copper, 35% silver and 9% manganese. Since 2000, dollar coins, for example the Sacagawea dollar and the Presidential $1 coins, are made from a brass containing 7% of manganese with a pure copper core.[37] In both cases of nickel and dollar, the use of manganese in the coin was to duplicate the electromagnetic properties of a previous identically sized and valued coin, for vending purposes. In the case of the later U.S. dollar coins, the manganese alloy was an attempt to duplicate properties of the copper/nickel alloy used in the previous Susan B. Anthony dollar.

Manganese compounds have been used as pigments and for the coloring of ceramics and glass. The brown color of ceramic is sometimes based on manganese compounds.[38] In the glass industry, manganese compounds are used for two effects. Manganese(III) reacts with iron(II) to induce a strong green color in glass by forming less-colored iron(III) and slightly pink manganese(II), compensating for the residual color of the iron(III).[13] Larger amounts of manganese are used to produce pink colored glass.

Biological role

Reactive center of arginase with boronic acid inhibitor - the manganese atoms are shown in yellow.

Manganese is an essential trace nutrient in all forms of life.[19] The classes of enzymes that have manganese cofactors are very broad, and include oxidoreductases, transferases, hydrolases, lyases, isomerases, ligases, lectins, and integrins. The reverse transcriptases of many retroviruses (though not lentiviruses such as HIV) contain manganese. The best-known manganese-containing polypeptides may be arginase, the diphtheria toxin, and Mn-containing superoxide dismutase (Mn-SOD).[39]

Mn-SOD is the type of SOD present in eukaryotic mitochondria, and also in most bacteria (this fact is in keeping with the bacterial-origin theory of mitochondria). The Mn-SOD enzyme is probably one of the most ancient, for nearly all organisms living in the presence of oxygen use it to deal with the toxic effects of superoxide, formed from the 1-electron reduction of dioxygen. Exceptions include a few kinds of bacteria, such as Lactobacillus plantarum and related lactobacilli, which use a different nonenzymatic mechanism, involving manganese (Mn2+) ions complexed with polyphosphate directly for this task, indicating how this function possibly evolved in aerobic life.

The human body contains about 12 mg of manganese, which is stored mainly in the bones; in the tissue, it is mostly concentrated in the liver and kidneys.[19] In the human brain, the manganese is bound to manganese metalloproteins, most notably glutamine synthetase in astrocytes.[40]

Manganese is also important in photosynthetic oxygen evolution in chloroplasts in plants. The oxygen-evolving complex (OEC) is a part of photosystem II contained in the thylakoid membranes of chloroplasts; it is responsible for the terminal photooxidation of water during the light reactions of photosynthesis, and has a metalloenzyme core containing four atoms of manganese.[41] For this reason, most broad-spectrum plant fertilizers contain manganese.

Precautions

Manganese compounds are less toxic than those of other widespread metals, such as nickel and copper.[42] However, exposure to manganese dusts and fumes should not exceed the ceiling value of 5 mg/m3 even for short periods because of its toxicity level.[43] Manganese poisoning has been linked to impaired motor skills and cognitive disorders.[44]

The permanganate exhibits a higher toxicity than the manganese(II) compounds. The fatal dose is about 10 g, and several fatal intoxications have occurred. The strong oxidative effect leads to necrosis of the mucous membrane. For example, the esophagus is affected if the permanganate is swallowed. Only a limited amount is absorbed by the intestines, but this small amount shows severe effects on the kidneys and on the liver.[45][46]

In 2005, a study suggested a possible link between manganese inhalation and central nervous system toxicity in rats.[47]

Manganese exposure in United States is regulated by Occupational Safety and Health Administration.[48]

Generally, exposure to ambient Mn air concentrations in excess of 5 μg Mn/m3 can lead to Mn-induced symptoms. Increased ferroportin protein expression in human embryonic kidney (HEK293) cells is associated with decreased intracellular Mn concentration and attenuated cytotoxicity, characterized by the reversal of Mn-reduced glutamate uptake and diminished lactate dehydrogenase leakage.[49]

Environmental health concerns

Manganese in drinking water

Waterborne manganese has a greater bioavailability than dietary manganese. According to results from a 2010 study,[50] higher levels of exposure to manganese in drinking water are associated with increased intellectual impairment and reduced intelligence quotients in school-age children. It is hypothesized that long-term exposure to the naturally occurring manganese in shower water puts up to 8.7 million Americans at risk.[47][51][52]

Manganese in gasoline

Methylcyclopentadienyl manganese tricarbonyl (MMT) is a gasoline additive used to replace lead compounds for unleaded gasolines, to improve the octane number in low octane number petrol distillates. It functions as an antiknock agent by the action of the carbonyl groups. Fuels containing manganese tend to form manganese carbides, which damage exhaust valves. The need to use lead or manganese compounds is merely historic, as the availability of reformation processes which create high-octane rating fuels increased. The use of such fuels directly or in mixture with non-reformed distillates is universal in developped countries (EU, Japan, etc.). In USA the imperative to provide the lowest possible price per volume on motor fuels (low fuel taxation rate) and lax legistation of fuel content (before 2000) caused refineries to use MMT. Compared to 1953, levels of manganese in air have dropped.[53] Many racing competitions specifically ban manganese compunds in racing fuel (cart, minibike). MMT contains 24.4-25.2% manganese. There is strong correlation between elevated atmospheric manganese concentrations and automobile traffic density.

Role in neurological disorders

Manganism

Manganese overexposure is most frequently associated with manganism, a rare neurological disorder associated with excessive manganese inhalation. Historically, persons employed in the production or processing of manganese alloys[54][55] have been at risk for developing manganism; however, current health and safety regulations protect workers in developed nations.[48] The disorder was first described in 1837 by British academic James Couper, who studied two patients who were manganese grinders.[56]

Manganism is a biphasic disorder. In its early stages, an intoxicated person may experience depression, mood swings, strange compulsive behaviors, psychosis and hallucinations; this stage is sometimes called "manganese madness". Early neurological symptoms give way to late-stage manganism, which resembles Parkinson's disease. Symptoms include weakness, monotone and slowed speech, an expressionless face, tremor, forward-leaning gait, inability to walk backwards without falling, rigidity, and general problems with dexterity, gait and balance.[56][57] Unlike Parkinson's disease, manganism is not associated with loss of smell and patients are typically unresponsive to treatment with levodopa.[58] Symptoms of late-stage manganism become more severe over time even if the source of exposure is removed and brain manganese levels return to normal.[57]

Childhood developmental disorders

Several recent studies attempt to examine the effects of chronic low-dose manganese overexposure on development in children. The earliest study of this kind was conducted in the Chinese province of Shanxi. Drinking water there had been contaminated through improper sewage irrigation and contained 240-350 µg Mn/L. Although WMn concentrations at or below 300 µg Mn/L are considered safe by the US EPA and 500 µg Mn/L are considered safe by the WHO, the 92 children sampled (between 11 and 13 years of age) from this province displayed lower performance on tests of manual dexterity and rapidity, short-term memory, and visual identification when compared to children from an uncontaminated area. More recently, a study of 10-year-old children in Bangladesh showed a relationship between WMn concentration in well water and diminished IQ scores. A third study conducted in Quebec examined school children between the ages of 6 and 15 living in homes that received water from a well containing 610 µg Mn/L; controls lived in homes that received water from a 160 µg Mn/L well. Children in the experimental group showed increased hyperactive and oppositional behaviours.[50]

Neurodegenerative diseases

Chronic low-dose manganese intoxication is strongly implicated in a number of neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. It may also play a role in the development of multiple sclerosis, restless leg syndrome, and Huntington's disease. A protein called DMT1 is the major transporter involved in manganese absorption from the intestine, and may be the major transporter of manganese across the blood-brain barrier. DMT1 also transports inhaled manganese across the nasal epithelium. The putative mechanism of action is that manganese overexposure and/or dysregulation leads to oxidative stress, mitochondrial dysfunction, glutamate-mediated excitoxicity, and aggregates of protein.

See also

References

  1. ^ a b c d Holleman, Arnold F.; Wiberg, Egon; Wiberg, Nils; (1985). "Mangan" (in German). Lehrbuch der Anorganischen Chemie (91–100 ed.). Walter de Gruyter. pp. 1110–1117. ISBN 3-11-007511-3. 
  2. ^ Lide, David R. (2004). Magnetic susceptibility of the elements and inorganic compounds, in Handbook of Chemistry and Physics. CRC press. ISBN 0849304857. http://www-d0.fnal.gov/hardware/cal/lvps_info/engineering/elementmagn.pdf. 
  3. ^ a b c Audi, Georges (2003). "The NUBASE Evaluation of Nuclear and Decay Properties". Nuclear Physics A (Atomic Mass Data Center) 729: 3–128. Bibcode 2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001. 
  4. ^ Schaefer, Jeorg; et. al (2006). "Terrestrial manganese-53 — A new monitor of Earth surface processes". Earth and Planetary Science Letters 251 (3–4): 334–345. Bibcode 2006E&PSL.251..334S. doi:10.1016/j.epsl.2006.09.016. 
  5. ^ Rayner-Canham, Geoffrey and Overton, Tina Descriptive Inorganic Chemistry, Macmillan, 2003. p. 491 ISBN 0716746204.
  6. ^ Schmidt, Max (1968). "VII. Nebengruppe" (in German). Anorganische Chemie II.. Wissenschaftsverlag. pp. 100–109. 
  7. ^ Temple, R. B.; Thickett, G. W. (1972). "The formation of manganese(v) in molten sodium nitrite". Australian Journal of Chemistry 25: 55. http://www.publish.csiro.au/?act=view_file&file_id=CH9720655.pdf. 
  8. ^ Luft, J. H. (1956). "Permanganate – a new fixative for electron microscopy". Journal of Biophysical and Biochemical Cytology 2 (6): 799–802. doi:10.1083/jcb.2.6.799. PMC 2224005. PMID 13398447. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2224005. 
  9. ^ Calvert, J.B. (2003-01-24). "Chromium and Manganese". http://www.du.edu/~jcalvert/phys/chromang.htm. Retrieved 2009-04-30. 
  10. ^ Chalmin, Emilie; Menu, Michel; Vignaud, Colette (2003). "Analysis of rock art painting and technology of Palaeolithic painters". Measurement Science and Technology 14 (9): 1590–1597. doi:10.1088/0957-0233/14/9/310. 
  11. ^ Chalmin, Y; Osuga, Y; Harada, M; Hirata, T; Koga, K; Morimoto, C; Hirota, Y; Yoshino, O et al; Vignaud, C.; Salomon, H.; Farges, F.; Susini, J.; Menu, M. (2006). "Minerals discovered in paleolithic black pigments by transmission electron microscopy and micro-X-ray absorption near-edge structure". Applied Physics A 83 (12): 213–218. Bibcode 2006ApPhA..83..213C. doi:10.1007/s00339-006-3510-7. PMID 16055459. 
  12. ^ Sayre, E. V.; Smith, R. W. (1961). "Compositional Categories of Ancient Glass". Science 133 (3467): 1824–1826. Bibcode 1961Sci...133.1824S. doi:10.1126/science.133.3467.1824. PMID 17818999. 
  13. ^ a b c Mccray, W. Patrick (1998). "Glassmaking in renaissance Italy: The innovation of venetian cristallo". Journal of the Minerals, Metals and Materials Society 50 (5): 14. Bibcode 1998JOM....50e..14M. doi:10.1007/s11837-998-0024-0. 
  14. ^ Rancke-Madsen, E. (1975). "The Discovery of an Element". Centaurus 19 (4): 299–313. Bibcode 1975Cent...19..299R. doi:10.1111/j.1600-0498.1975.tb00329.x. 
  15. ^ Alessio, L; Campagna, M; Lucchini, R (2007). "From lead to manganese through mercury: mythology, science, and lessons for prevention". American journal of industrial medicine 50 (11): 779–787. doi:10.1002/ajim.20524. PMID 17918211. 
  16. ^ Couper, J. (1837). "On the effects of black oxide of manganese when inhaled into the lungs". Br. Ann. Med. Pharm. 1: 41–42. 
  17. ^ Olsen, Sverre E.; Tangstad, Merete; Lindstad, Tor (2007). "History of manganese". Production of Manganese Ferroalloys. Tapir Academic Press. pp. 11–12. ISBN 9788251921916. 
  18. ^ a b Preisler, Eberhard (1980). "Moderne Verfahren der Großchemie: Braunstein" (in German). Chemie in unserer Zeit 14 (5): 137–148. doi:10.1002/ciuz.19800140502. 
  19. ^ a b c d e Emsley, John (2001). "Manganese". Nature's Building Blocks: An A-Z Guide to the Elements. Oxford, UK: Oxford University Press. pp. 249–253. ISBN 0-19-850340-7. http://books.google.com/?id=j-Xu07p3cKwC. 
  20. ^ Bhattacharyya, P. K.; Dasgupta, Somnath; Fukuoka, M.; Roy Supriya (1984). "Geochemistry of braunite and associated phases in metamorphosed non-calcareous manganese ores of India". Contributions to Mineralogy and Petrology 87 (1): 65–71. Bibcode 1984CoMP...87...65B. doi:10.1007/BF00371403. 
  21. ^ a b c d Corathers, Lisa A. (2009). "Mineral Commodity Summaries 2009: Manganese" (PDF). United States Geological Survey. http://minerals.usgs.gov/minerals/pubs/commodity/manganese/mcs-2009-manga.pdf. Retrieved 2009-04-30. 
  22. ^ Wang, X; Schröder, Hc; Wiens, M; Schlossmacher, U; Müller, We (2009). "Manganese/polymetallic nodules: micro-structural characterization of exolithobiontic- and endolithobiontic microbial biofilms by scanning electron microscopy". Micron (Oxford, England : 1993) 40 (3): 350–358. doi:10.1016/j.micron.2008.10.005. ISSN 0968-4328. PMID 19027306. 
  23. ^ United Nations Ocean Economics and Technology Office, Technology Branch, United Nations (1978). Manganese Nodules: Dimensions and Perspectives. Springer. ISBN 9789027705006. 
  24. ^ a b Corathers, Lisa A. (June 2008). "2006 Minerals Yearbook: Manganese" (PDF). Washington, D.C.: United States Geological Survey. http://minerals.usgs.gov/minerals/pubs/commodity/manganese/myb1-2006-manga.pdf. Retrieved 2009-04-30. 
  25. ^ Corathers, L. A.; Machamer, J. F. (2006). "Manganese". Industrial Minerals & Rocks: Commodities, Markets, and Uses (7th ed.). SME. pp. 631–636. ISBN 9780873352338. http://books.google.com/?id=zNicdkuulE4C&pg=PA631. 
  26. ^ a b Zhang, Wensheng; Cheng, Chu Yong (2007). "Manganese metallurgy review. Part I: Leaching of ores/secondary materials and recovery of electrolytic/chemical manganese dioxide". Hydrometallurgy 89 (3–4): 137–159. doi:10.1016/j.hydromet.2007.08.010. 
  27. ^ Verhoeven, John D. (2007). Steel metallurgy for the non-metallurgist. Materials Park, Ohio: ASM International. pp. 56–57. ISBN 9780871708588. 
  28. ^ Dastur, Y. N.; Leslie, W. C. (1981). "Mechanism of work hardening in Hadfield manganese steel". Metallurgical Transactions A 12 (5): 749. Bibcode 1981MTA....12..749D. doi:10.1007/BF02648339. 
  29. ^ Stansbie, John Henry (2007). Iron and Steel. Read Books. pp. 351–352. ISBN 9781408626160. http://books.google.com/?id=FyogLqUxW1cC&pg=PA351. 
  30. ^ Brady, George S.; Clauser; Henry R.; Vaccari. John A. (2002). Materials handbook : an encyclopedia for managers, technical professionals, purchasing and production managers, technicians, and supervisors. New York, NY: McGraw-Hill. pp. 585–587. ISBN 9780071360760. http://books.google.com/?id=vIhvSQLhhMEC&pg=PA585. 
  31. ^ Tweedale, Geoffrey (1985). "Sir Robert Abbott Hadfield F.R.S. (1858–1940), and the Discovery of Manganese Steel Geoffrey Tweedale". Notes and Records of the Royal Society of London 40 (1): 63–74. doi:10.1098/rsnr.1985.0004. JSTOR 531536. 
  32. ^ "chemical properties of 2024 aluminum allow". Metal Suppliers Online, LLC.. http://www.suppliersonline.com/propertypages/2024.asp. Retrieved 2009-04-30. 
  33. ^ a b Kaufman, John Gilbert (2000). "Applications for Aluminium Alloys and Tempers". Introduction to aluminum alloys and tempers. ASM International. pp. 93–94. ISBN 9780871706898. http://books.google.com/?id=idmZIDcwCykC&pg=PA93. 
  34. ^ Graham, L. A. et al. (2005). "Manganese(I) poly(mercaptoimidazolyl)borate complexes: spectroscopic and structural characterization of MnH–B interactions in solution and in the solid state". Dalton Transactions (1): 171–180. doi:10.1039/b412280a. PMID 15605161. 
  35. ^ a b Dell, R. M. (2000). "Batteries fifty years of materials development". Solid State Ionics 134: 139–158. doi:10.1016/S0167-2738(00)00722-0. 
  36. ^ Kuwahara, Raymond T.; Skinner III, Robert B.; Skinner Jr., Robert B. (2001). "Nickel coinage in the United States". Western Journal of Medicine 175 (2): 112–114. doi:10.1136/ewjm.175.2.112. PMC 1071501. PMID 11483555. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1071501. 
  37. ^ Design of the Sacagawea dollar. United States Mint. http://www.usmint.gov/mint_programs/golden_dollar_coin/index.cfm?action=sacDesign. Retrieved 2009-05-04. 
  38. ^ Shepard, Anna Osler (1956). "Manganese and Iron–Manganese Paints". Ceramics for the archaeologist. Carnegie Institution of Washington. pp. 40–42. ISBN 9780872796201. 
  39. ^ Law, N.; Caudle, M; Pecoraro, V (1998). Manganese Redox Enzymes and Model Systems: Properties, Structures, and Reactivity. 46. p. 305. doi:10.1016/S0898-8838(08)60152-X. 
  40. ^ Takeda, A. (2003). "Manganese action in brain function". Brain Research Reviews 41 (1): 79. doi:10.1016/S0165-0173(02)00234-5. PMID 12505649. 
  41. ^ Dismukes, G. Charles; Willigen, Rogier T. van (2006). "Manganese: The Oxygen-Evolving Complex & Models". Encyclopedia of Inorganic Chemistry. doi:10.1002/0470862106.ia128. 
  42. ^ Hasan, Heather (2008). Manganese. The Rosen Publishing Group. pp. 31. ISBN 9781404214088. http://books.google.com/?id=nRmpEaudmTYC&pg=PA31. 
  43. ^ "Manganese Chemical Background". Metcalf Institute for Marine and Environmental Reporting University of Rhode Island. 2006-04. http://www.environmentwriter.org/resources/backissues/chemicals/manganese.htm. Retrieved 2008-04-30. 
  44. ^ "Risk Assessment Information System Toxicity Summary for Manganese". Oak Ridge National Laboratory. http://rais.ornl.gov/tox/profiles/mn.html. Retrieved 2008-04-23. 
  45. ^ Ong, K. L.; Tan, TH; Cheung, WL (1997). "Potassium permanganate poisoning—a rare cause of fatal self poisoning". Emergency Medicine Journal 14 (1): 43–5. doi:10.1136/emj.14.1.43. PMC 1342846. PMID 9023625. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1342846. 
  46. ^ Young, R.; Critchley, JA; Young, KK; Freebairn, RC; Reynolds, AP; Lolin, YI (1996). "Fatal acute hepatorenal failure following potassium permanganate ingestion". Human & Experimental Toxicology 15 (3): 259–61. doi:10.1177/096032719601500313. PMID 8839216. 
  47. ^ a b Elsner, RJ; Spangler, JG; Spangler, John G. (2005). "Neurotoxicity of inhaled manganese: Public health danger in the shower?". Medical Hypotheses 65 (3): 607–616. doi:10.1016/j.mehy.2005.01.043. PMID 15913899. 
  48. ^ a b "Safety and Health Topics: Manganese Compounds (as Mn)". http://www.osha.gov/dts/chemicalsampling/data/CH_250190.html. 
  49. ^ Yin, Z; Jiang, H; Lee, ES; Ni, M; Erikson, KM; Milatovic, D; Bowman, AB; Aschner, M (2010). "Ferroportin is a manganese-responsive protein that decreases manganese cytotoxicity and accumulation". Journal of neurochemistry 112 (5): 1190–8. doi:10.1111/j.1471-4159.2009.06534.x. PMC 2819584. PMID 20002294. http://libres.uncg.edu/ir/uncg/f/K_Erickson_Ferroportin_2009.pdf. , and also: Cotzias et al. 1968; Olanow 2004; Aschner et al. 2007; Ellingsen et al. 2008
  50. ^ a b Bouchard, Maryse F.; Sébastien Sauvé, Benoit Barbeau, Melissa Legrand, Marie-Ève Brodeur, Thérèse Bouffard, Elyse Limoges, David C. Bellinger and Donna Mergler (20 September 2010). "Intellectual Impairment in School-Age Children". Environmental Health Perspectives 119 (1): 138–143. doi:10.1289/ehp.1002321. PMC 3018493. PMID 20855239. http://www.cityofmadison.com/water/waterQuality/documents/EHP.20100920.MnIQ.pdf. Retrieved 11 December 2010. 
  51. ^ Finley, John Weldon; Davis, Cindy D. (1999). "Manganese deficiency and toxicity: Are high or low dietary amounts of manganese cause for concern?". BioFactors 10: 15. doi:10.1002/biof.5520100102. 
  52. ^ Barceloux, Donald; Barceloux, Donald (1999). "Manganese". Clinical Toxicology 37 (2): 293. doi:10.1081/CLT-100102427. 
  53. ^ www.atsdr.cdc.gov/toxprofiles/tp151-c6.pdf
  54. ^ Baselt, R. Disposition of Toxic Drugs and Chemicals in Man, 8th edition, Biomedical Publications, Foster City, CA, 2008, pp. 883–886 ISBN 0962652377.
  55. ^ Normandin, Louise; Hazell, AS (2002). "Manganese neurotoxicity: an update of pathophysiologic mechanisms". Metabolic Brain Disease 17 (4): 375–87. doi:10.1023/A:1021970120965. PMID 12602514. 
  56. ^ a b Couper, John (1837). "On the effects of black oxide of manganese when inhaled into the lungs.". Br. Ann. Med. Pharm. Vital. Stat. Gen. Sci. 1: 41–42. 
  57. ^ a b Cersosimo, M.G.; Koller, W.C. (2007). "The diagnosis of manganese-induced parkinsonism.". NeuroToxicology 27: 340–346. 
  58. ^ Lu, C.S.; Huang, C.C, Chu, N.S., Calne, D.B. (1994). "Levodopa failure in chronic manganism.". Neurology 44: 1600–1602. 

External links


Translations:

Manganese

Top

Dansk (Danish)
n. - [kem.] mangan

Nederlands (Dutch)
mangaan (metaalachtig element)

Français (French)
n. - manganèse

Deutsch (German)
n. - (Chem.) Mangan, Braunstein

Ελληνική (Greek)
n. - (χημ.) μαγγάνιο

Italiano (Italian)
manganese

Português (Portuguese)
n. - manganês (m)

Русский (Russian)
марганец

Español (Spanish)
n. - manganeso

Svenska (Swedish)
n. - mangan (kem.), brunsten (miner.)

中文(简体)(Chinese (Simplified))

中文(繁體)(Chinese (Traditional))
n. - 錳

한국어 (Korean)
n. - 망간

日本語 (Japanese)
n. - マンガン

العربيه (Arabic)
‏(الاسم) المنغنيز‏

עברית (Hebrew)
n. - ‮מנגן (יסוד מתכתי, NM, מספר אטומי 52)‬


 
 
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Mn2+
manganiferous
Mn

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