68-620: (Redirected from Tc ) [REDACTED] Look up Tc , .tc , or TC in Wiktionary, the free dictionary. TC , T.C. , Tc , T c , tc , tC , or .tc may refer to: Arts and entertainment [ edit ] Film and television [ edit ] Theodore "T.C." Calvin, a character on the TV series Magnum, P.I. and its reboot Tom Caron , American television host for New England Sports Network Top Cat , an animated sitcom named after
136-417: A fission product yield of 6.1%. Other fissile isotopes produce similar yields of technetium, such as 4.9% from uranium-233 and 6.21% from plutonium-239 . An estimated 49,000 T Bq (78 metric tons ) of technetium was produced in nuclear reactors between 1983 and 1994, by far the dominant source of terrestrial technetium. Only a fraction of the production is used commercially. Technetium-99
204-575: A half-life of 4.21 ± 0.16 million years and technetium-98 with 4.2 ± 0.3 million years; current measurements of their half-lives give overlapping confidence intervals corresponding to one standard deviation and therefore do not allow a definite assignment of technetium's most stable isotope. The next most stable isotope is technetium-99, which has a half-life of 211,100 years. Thirty-four other radioisotopes have been characterized with mass numbers ranging from 86 to 122. Most of these have half-lives that are less than an hour,
272-433: A molybdenum foil that had been part of the deflector in the cyclotron. Segrè enlisted his colleague Perrier to attempt to prove, through comparative chemistry, that the molybdenum activity was indeed from an element with the atomic number 43. In 1937, they succeeded in isolating the isotopes technetium-95m and technetium-97 . University of Palermo officials wanted them to name their discovery panormium , after
340-445: A shielded column chromatograph inside a technetium-99m generator ("technetium cow", also occasionally called a "molybdenum cow"). Molybdenum-99 has a half-life of 67 hours, so short-lived technetium-99m (half-life: 6 hours), which results from its decay, is being constantly produced. The soluble pertechnetate TcO 4 can then be chemically extracted by elution using a saline solution . A drawback of this process
408-496: A spontaneous fission product of uranium-238 . The natural nuclear fission reactor in Oklo contains evidence that significant amounts of technetium-99 were produced and have since decayed into ruthenium-99 . Technetium is a silvery-gray radioactive metal with an appearance similar to platinum , commonly obtained as a gray powder. The crystal structure of the bulk pure metal is hexagonal close-packed , and crystal structures of
476-531: A type-II superconductor at temperatures below 7.46 K . Below this temperature, technetium has a very high magnetic penetration depth , greater than any other element except niobium . Technetium is located in the group 7 of the periodic table, between rhenium and manganese . As predicted by the periodic law , its chemical properties are between those two elements. Of the two, technetium more closely resembles rhenium, particularly in its chemical inertness and tendency to form covalent bonds . This
544-585: A Mazda piston engine Chrysler TC by Maserati , an automobile sold by Chrysler from 1989 to 1991 Scion tC , a touring coupe produced by Scion based on the Toyota Avensis Traction control system , an anti-slip automobile subsystem Turn coordinator , an aircraft instrument Transit center , a major transport hub for trains and buses Other uses in science and technology [ edit ] Technical committee, see All pages with titles containing Technical committee Teleconverter ,
612-462: A U.S. Article I federal trial court Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title TC . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=TC&oldid=1244586746 " Category : Disambiguation pages Hidden categories: Short description
680-480: A beam of electrons and deduced element 43 was present by examining X-ray emission spectrograms . The wavelength of the X-rays produced is related to the atomic number by a formula derived by Henry Moseley in 1913. The team claimed to detect a faint X-ray signal at a wavelength produced by element 43. Later experimenters could not replicate the discovery, and it was dismissed as an error. Still, in 1933,
748-526: A chemical element Temperature coefficient Critical temperature (T c ) Convective temperature (T c ) Curie temperature (T c ) Teracoulomb , an SI unit for electric charge equal to 10 coulombs Tesla coil , a category of high-voltage discharge coils Tonnes of Carbon (tC) Computing [ edit ] Turing complete .tc , the Internet country code top-level domain (ccTLD) for Turks and Caicos Islands TC (complexity) ,
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#1732852857579816-570: A complexity class Tc (Linux) , a command-line utility used to configure network traffic control in the Linux kernel Take Command (command line interpreter) , a command line interpreter by JP Software Telecine (copying) , a form of digital transfer using a Telecine machine Teleconference TrueCrypt , a disk encryption software Trusted Computing , a scheme for adding additional controls on what computers may or may not do into hardware or software Transportation [ edit ] TC ,
884-472: A diversified mining company Transport Canada , a Canadian federal government department Trinity College (Connecticut) , an American liberal arts college Tomball College, now Lone Star College-Tomball Transport Canberra , Australian transport agency People [ edit ] TC Clements , Michigan state representative Tony Currie (footballer) (born 1950), English footballer Places [ edit ] The Republic of Turkey , from
952-476: A gap between molybdenum (element 42) and ruthenium (element 44). In 1871, Mendeleev predicted this missing element would occupy the empty place below manganese and have similar chemical properties. Mendeleev gave it the provisional name eka-manganese (from eka , the Sanskrit word for one ) because it was one place down from the known element manganese. Many early researchers, both before and after
1020-486: A kind of secondary photographic lens Timecode , in video and audio production Tropical cyclone , also known as a hurricane, tropical storm, tropical depression, or typhoon Turbocharger , turbine-driven device that increases an internal combustion engine's power output Sports [ edit ] T.C. Bear , mascot for the Minnesota Twins baseball team TC 2000 , a series of races for touring cars which
1088-426: A major concern for long-term disposal of radioactive waste . Many of the processes designed to remove fission products in reprocessing plants aim at cationic species such as caesium (e.g., caesium-137 ) and strontium (e.g., strontium-90 ). Hence the pertechnetate escapes through those processes. Current disposal options favor burial in continental, geologically stable rock. The primary danger with such practice
1156-451: A series of articles on the discovery of elements quoted the name masurium for element 43. Some more recent attempts have been made to rehabilitate the Noddacks' claims, but they are disproved by Paul Kuroda 's study on the amount of technetium that could have been present in the ores they studied: it could not have exceeded 3 × 10 μg/kg of ore, and thus would have been undetectable by
1224-561: A three-dimensional network. These compounds are produced by combining the metal and halogen or by less direct reactions. TcCl 4 is obtained by chlorination of Tc metal or Tc 2 O 7 . Upon heating, TcCl 4 gives the corresponding Tc(III) and Tc(II) chlorides. The structure of TcCl 4 is composed of infinite zigzag chains of edge-sharing TcCl 6 octahedra. It is isomorphous to transition metal tetrachlorides of zirconium , hafnium , and platinum . Two polymorphs of technetium trichloride exist, α- and β-TcCl 3 . The α polymorph
1292-732: A trioxide has not been isolated for technetium. However, TcO 3 has been identified in the gas phase using mass spectrometry . Technetium forms the complex TcH 9 . The potassium salt is isostructural with ReH 9 . At high pressure formation of TcH 1.3 from elements was also reported. The following binary (containing only two elements) technetium halides are known: TcF 6 , TcF 5 , TcCl 4 , TcBr 4 , TcBr 3 , α-TcCl 3 , β-TcCl 3 , TcI 3 , α-TcCl 2 , and β-TcCl 2 . The oxidation states range from Tc(VI) to Tc(II). Technetium halides exhibit different structure types, such as molecular octahedral complexes, extended chains, layered sheets, and metal clusters arranged in
1360-453: Is a metastable nuclear isomer) is used in radioactive isotope medical tests . For example, technetium-99m is a radioactive tracer that medical imaging equipment tracks in the human body. It is well suited to the role because it emits readily detectable 140 keV gamma rays , and its half-life is 6.01 hours (meaning that about 94% of it decays to technetium-99 in 24 hours). The chemistry of technetium allows it to be bound to
1428-405: Is a goal, an extremely pure technetium target is needed; if small traces of the minor actinides such as americium and curium are present in the target, they are likely to undergo fission and form more fission products which increase the radioactivity of the irradiated target. The formation of ruthenium-106 (half-life 374 days) from the 'fresh fission' is likely to increase the activity of
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#17328528575791496-448: Is a major product of the fission of uranium-235 ( U), making it the most common and most readily available isotope of technetium. One gram of technetium-99 produces 6.2 × 10 disintegrations per second (in other words, the specific activity of Tc is 0.62 G Bq /g). Technetium occurs naturally in the Earth's crust in minute concentrations of about 0.003 parts per trillion. Technetium
1564-406: Is a molecular metal oxide, analogous to manganese heptoxide . It adopts a centrosymmetric structure with two types of Tc−O bonds with 167 and 184 pm bond lengths. Technetium heptoxide hydrolyzes to pertechnetate and pertechnetic acid , depending on the pH: HTcO 4 is a strong acid. In concentrated sulfuric acid , [TcO 4 ] converts to the octahedral form TcO 3 (OH)(H 2 O) 2 ,
1632-707: Is a white volatile solid. In this molecule, two technetium atoms are bound to each other; each atom is surrounded by octahedra of five carbonyl ligands. The bond length between technetium atoms, 303 pm, is significantly larger than the distance between two atoms in metallic technetium (272 pm). Similar carbonyls are formed by technetium's congeners , manganese and rhenium. Interest in organotechnetium compounds has also been motivated by applications in nuclear medicine . Technetium also forms aquo-carbonyl complexes, one prominent complex being [Tc(CO) 3 (H 2 O) 3 ] , which are unusual compared to other metal carbonyls. Technetium, with atomic number Z = 43,
1700-433: Is allowed to stand for several years before reprocessing, all molybdenum-99 and technetium-99m is decayed by the time that the fission products are separated from the major actinides in conventional nuclear reprocessing . The liquid left after plutonium–uranium extraction ( PUREX ) contains a high concentration of technetium as TcO 4 but almost all of this is technetium-99, not technetium-99m. The vast majority of
1768-421: Is also denoted as Tc 3 Cl 9 . It adopts a confacial bioctahedral structure . It is prepared by treating the chloro-acetate Tc 2 (O 2 CCH 3 ) 4 Cl 2 with HCl. Like Re 3 Cl 9 , the structure of the α-polymorph consists of triangles with short M-M distances. β-TcCl 3 features octahedral Tc centers, which are organized in pairs, as seen also for molybdenum trichloride . TcBr 3 does not adopt
1836-663: Is consistent with the tendency of period 5 elements to resemble their counterparts in period 6 more than period 4 due to the lanthanide contraction . Unlike manganese, technetium does not readily form cations ( ions with net positive charge). Technetium exhibits nine oxidation states from −1 to +7, with +4, +5, and +7 being the most common. Technetium dissolves in aqua regia , nitric acid , and concentrated sulfuric acid , but not in hydrochloric acid of any concentration. Metallic technetium slowly tarnishes in moist air and, in powder form, burns in oxygen . When reacting with hydrogen at high pressure, it forms
1904-419: Is contaminated with carbon ( a = 0.2805(4), b = 0.4958(8), c = 0.4474(5)·nm for Tc-C with 1.38 wt% C and a = 0.2815(4), b = 0.4963(8), c = 0.4482(5)·nm for Tc-C with 1.96 wt% C ). The metal form is slightly paramagnetic , meaning its magnetic dipoles align with external magnetic fields , but will assume random orientations once the field is removed. Pure, metallic, single-crystal technetium becomes
1972-1271: Is continuously produced as a fission product from the fission of uranium or plutonium in nuclear reactors : U 92 238 → sf I 53 137 + Y 39 99 + 2 0 1 n {\displaystyle {\ce {^{238}_{92}U ->[{\ce {sf}}] ^{137}_{53}I + ^{99}_{39}Y + 2^{1}_{0}n}}} Y 39 99 → 1.47 s β − Zr 40 99 → 2.1 s β − Nb 41 99 → 15.0 s β − Mo 42 99 → 65.94 h β − Tc 43 99 → 211 , 100 y β − Ru 44 99 {\displaystyle {\ce {^{99}_{39}Y ->[\beta^-][1.47\,{\ce {s}}] ^{99}_{40}Zr ->[\beta^-][2.1\,{\ce {s}}] ^{99}_{41}Nb ->[\beta^-][15.0\,{\ce {s}}] ^{99}_{42}Mo ->[\beta^-][65.94\,{\ce {h}}] ^{99}_{43}Tc ->[\beta^-][211,100\,{\ce {y}}] ^{99}_{44}Ru}}} Because used fuel
2040-462: Is different from Wikidata All article disambiguation pages All disambiguation pages Tc">Tc The requested page title contains unsupported characters : ">". Return to Main Page . Technetium Technetium is a chemical element ; it has symbol Tc and atomic number 43. It is the lightest element whose isotopes are all radioactive . Technetium and promethium are
2108-934: Is held each year in Argentina TC Panther, the mascot of the Northern Iowa Panthers Total chances , a baseball fielding term Turismo Carretera , a popular stock car category in Argentina Other uses [ edit ] Total Communication , a form of sign language Total cost , in economics and accounting Traffic collision , an automobile accident Trinity Cross , the highest national award in Trinidad and Tobago Type certificate , an aircraft document Traditional Chinese characters , Chinese characters in any character set that does not contain newly created characters or character substitutions performed after 1946 United States Tax Court ,
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2176-447: Is produced by radioactive decay from [ MoO 4 ] : Pertechnetate ( TcO 4 ) is only weakly hydrated in aqueous solutions, and it behaves analogously to perchlorate anion, both of which are tetrahedral . Unlike permanganate ( MnO 4 ), it is only a weak oxidizing agent . Related to pertechnetate is technetium heptoxide . This pale-yellow, volatile solid is produced by oxidation of Tc metal and related precursors: It
2244-453: Is produced by the nuclear fission of both uranium-235 and plutonium-239. It is therefore present in radioactive waste and in the nuclear fallout of fission bomb explosions. Its decay, measured in becquerels per amount of spent fuel, is the dominant contributor to nuclear waste radioactivity after about 10 ~10 years after the creation of the nuclear waste. From 1945–1994, an estimated 160 T Bq (about 250 kg) of technetium-99
2312-541: Is so rare because the half-lives of Tc and Tc are only 4.2 million years. More than a thousand of such periods have passed since the formation of the Earth , so the probability of survival of even one atom of primordial technetium is effectively zero. However, small amounts exist as spontaneous fission products in uranium ores . A kilogram of uranium contains an estimated 1 nanogram (10 g) equivalent to ten trillion atoms of technetium. Some red giant stars with
2380-672: Is that it requires targets containing uranium-235, which are subject to the security precautions of fissile materials. Almost two-thirds of the world's supply comes from two reactors; the National Research Universal Reactor at Chalk River Laboratories in Ontario, Canada, and the High Flux Reactor at Nuclear Research and Consultancy Group in Petten, Netherlands. All major reactors that produce technetium-99m were built in
2448-437: Is the likelihood that the waste will contact water, which could leach radioactive contamination into the environment. The anionic pertechnetate and iodide tend not to adsorb into the surfaces of minerals, and are likely to be washed away. By comparison plutonium , uranium , and caesium tend to bind to soil particles. Technetium could be immobilized by some environments, such as microbial activity in lake bottom sediments, and
2516-472: Is the lowest-numbered element in the periodic table for which all isotopes are radioactive . The second-lightest exclusively radioactive element, promethium , has atomic number 61. Atomic nuclei with an odd number of protons are less stable than those with even numbers, even when the total number of nucleons (protons + neutrons ) is even, and odd numbered elements have fewer stable isotopes . The most stable radioactive isotopes are technetium-97 with
2584-413: Is used as a protective reductant to keep plutonium in the trivalent rather than the more stable tetravalent state. The problem was exacerbated by the mutually enhanced solvent extraction of technetium and zirconium at the previous stage, and required a process modification. The most prevalent form of technetium that is easily accessible is sodium pertechnetate , Na[TcO 4 ]. The majority of this material
2652-613: The Xenosaga game series Organizations [ edit ] TC Electronic , a Danish manufacturer of studio equipment and guitar effects Air Tanzania (IATA code TC) Teachers College, Columbia University , a graduate school of education in New York City Telecom Cambodia , a telecom company in Cambodia Tierra Comunera , a Spanish political party Thompson Creek Metals Company Inc (NYSE: TC),
2720-427: The environmental chemistry of technetium is an area of active research. An alternative disposal method, transmutation , has been demonstrated at CERN for technetium-99. In this process, the technetium (technetium-99 as a metal target) is bombarded with neutrons to form the short-lived technetium-100 (half-life = 16 seconds) which decays by beta decay to stable ruthenium -100. If recovery of usable ruthenium
2788-425: The fission of uranium-235 in nuclear reactors and are extracted from nuclear fuel rods . Because even the longest-lived isotope of technetium has a relatively short half-life (4.21 million years), the 1952 detection of technetium in red giants helped to prove that stars can produce heavier elements . From the 1860s through 1871, early forms of the periodic table proposed by Dmitri Mendeleev contained
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2856-425: The neutron activation of molybdenum-98. When needed, other technetium isotopes are not produced in significant quantities by fission, but are manufactured by neutron irradiation of parent isotopes (for example, technetium-97 can be made by neutron irradiation of ruthenium-96 ). The feasibility of technetium-99m production with the 22-MeV-proton bombardment of a molybdenum-100 target in medical cyclotrons following
2924-427: The periodic table , and its chemical properties are intermediate between those of both adjacent elements. The most common naturally occurring isotope is Tc, in traces only. Many of technetium's properties had been predicted by Dmitri Mendeleev before it was discovered; Mendeleev noted a gap in his periodic table and gave the undiscovered element the provisional name ekamanganese ( Em ). In 1937, technetium became
2992-463: The 1960s and are close to the end of life . The two new Canadian Multipurpose Applied Physics Lattice Experiment reactors planned and built to produce 200% of the demand of technetium-99m relieved all other producers from building their own reactors. With the cancellation of the already tested reactors in 2008, the future supply of technetium-99m became problematic. The long half-life of technetium-99 and its potential to form anionic species creates
3060-511: The Latin name for Palermo , Panormus . In 1947, element 43 was named after the Greek word technetos ( τεχνητός ), meaning 'artificial', since it was the first element to be artificially produced. Segrè returned to Berkeley and met Glenn T. Seaborg . They isolated the metastable isotope technetium-99m , which is now used in some ten million medical diagnostic procedures annually. In 1952,
3128-834: The Noddacks' methods. The discovery of element 43 was finally confirmed in a 1937 experiment at the University of Palermo in Sicily by Carlo Perrier and Emilio Segrè . In mid-1936, Segrè visited the United States, first Columbia University in New York and then the Lawrence Berkeley National Laboratory in California. He persuaded cyclotron inventor Ernest Lawrence to let him take back some discarded cyclotron parts that had become radioactive . Lawrence mailed him
3196-500: The Turkish name, Türkiye Cumhuriyeti Traverse City, Michigan , US Turks and Caicos Islands (ISO 3166-1 country code TC) Science and technology [ edit ] Biology and medicine [ edit ] Testicular cancer Therapeutic community , a treatment program for addictions, personality disorder or other mental problems Cytotoxic T-cells Chemistry and physics [ edit ] Technetium , symbol Tc,
3264-418: The astronomer Paul W. Merrill in California detected the spectral signature of technetium (specifically wavelengths of 403.1 nm , 423.8 nm, 426.2 nm, and 429.7 nm) in light from S-type red giants . The stars were near the end of their lives but were rich in the short-lived element, which indicated that it was being produced in the stars by nuclear reactions . That evidence bolstered
3332-460: The conjugate base of the hypothetical tri aquo complex [TcO 3 (H 2 O) 3 ] . Technetium forms a dioxide , disulfide , di selenide , and di telluride . An ill-defined Tc 2 S 7 forms upon treating pertechnate with hydrogen sulfide. It thermally decomposes into disulfide and elemental sulfur. Similarly the dioxide can be produced by reduction of the Tc 2 O 7 . Unlike the case for rhenium,
3400-627: The environment is by the Sellafield plant, which released an estimated 550 TBq (about 900 kg) from 1995 to 1999 into the Irish Sea . From 2000 onwards the amount has been limited by regulation to 90 TBq (about 140 kg) per year. Discharge of technetium into the sea resulted in contamination of some seafood with minuscule quantities of this element. For example, European lobster and fish from west Cumbria contain about 1 Bq/kg of technetium. The metastable isotope technetium-99m
3468-486: The exception that technetium-100 can decay both by beta emission and electron capture. Technetium also has numerous nuclear isomers , which are isotopes with one or more excited nucleons. Technetium-97m ( Tc; "m" stands for metastability ) is the most stable, with a half-life of 91 days and excitation energy 0.0965 MeV. This is followed by technetium-95m (61 days, 0.03 MeV), and technetium-99m (6.01 hours, 0.142 MeV). Technetium-99 ( Tc)
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#17328528575793536-467: The exceptions being technetium-93 (2.73 hours), technetium-94 (4.88 hours), technetium-95 (20 hours), and technetium-96 (4.3 days). The primary decay mode for isotopes lighter than technetium-98 ( Tc) is electron capture , producing molybdenum ( Z = 42). For technetium-98 and heavier isotopes, the primary mode is beta emission (the emission of an electron or positron ), producing ruthenium ( Z = 44), with
3604-611: The final ruthenium metal, which will then require a longer cooling time after irradiation before the ruthenium can be used. The actual separation of technetium-99 from spent nuclear fuel is a long process. During fuel reprocessing , it comes out as a component of the highly radioactive waste liquid. After sitting for several years, the radioactivity reduces to a level where extraction of the long-lived isotopes, including technetium-99, becomes feasible. A series of chemical processes yields technetium-99 metal of high purity. Molybdenum-99 , which decays to form technetium-99m, can be formed by
3672-528: The first predominantly artificial element to be produced, hence its name (from the Greek technetos , 'artificial', + -ium ). One short-lived gamma ray –emitting nuclear isomer , technetium-99m , is used in nuclear medicine for a wide variety of tests, such as bone cancer diagnoses. The ground state of the nuclide technetium-99 is used as a gamma ray–free source of beta particles . Long-lived technetium isotopes produced commercially are byproducts of
3740-424: The hexahalides [TcX 6 ] (X = F, Cl, Br, I), which adopt octahedral molecular geometry . More reduced halides form anionic clusters with Tc–Tc bonds. The situation is similar for the related elements of Mo, W, Re. These clusters have the nuclearity Tc 4 , Tc 6 , Tc 8 , and Tc 13 . The more stable Tc 6 and Tc 8 clusters have prism shapes where vertical pairs of Tc atoms are connected by triple bonds and
3808-438: The hydride TcH 1.3 and while reacting with carbon it forms Tc 6 C, with cell parameter 0.398 nm, as well as the nanodisperce low-carbon-content carbide with parameter 0.402nm. Technetium can catalyse the destruction of hydrazine by nitric acid , and this property is due to its multiplicity of valencies. This caused a problem in the separation of plutonium from uranium in nuclear fuel processing , where hydrazine
3876-537: The hypothesis that heavier elements are the product of nucleosynthesis in stars. More recently, such observations provided evidence that elements are formed by neutron capture in the s-process . Since that discovery, there have been many searches in terrestrial materials for natural sources of technetium. In 1962, technetium-99 was isolated and identified in pitchblende from the Belgian Congo in very small quantities (about 0.2 ng/kg), where it originates as
3944-469: The nanodisperse pure metal are cubic . Nanodisperse technetium does not have a split NMR spectrum, while hexagonal bulk technetium has the Tc-99-NMR spectrum split in 9 satellites. Atomic technetium has characteristic emission lines at wavelengths of 363.3 nm , 403.1 nm, 426.2 nm, 429.7 nm, and 485.3 nm. The unit cell parameters of the orthorhombic Tc metal were reported when Tc
4012-451: The only radioactive elements whose neighbours in the sense of atomic number are both stable. All available technetium is produced as a synthetic element . Naturally occurring technetium is a spontaneous fission product in uranium ore and thorium ore (the most common source), or the product of neutron capture in molybdenum ores. This silvery gray, crystalline transition metal lies between manganese and rhenium in group 7 of
4080-553: The periodic table was published, were eager to be the first to discover and name the missing element. Its location in the table suggested that it should be easier to find than other undiscovered elements. This turned out not to be the case, due to technetium's radioactivity. German chemists Walter Noddack , Otto Berg , and Ida Tacke reported the discovery of element 75 and element 43 in 1925, and named element 43 masurium (after Masuria in eastern Prussia , now in Poland ,
4148-597: The planar atoms by single bonds. Every technetium atom makes six bonds, and the remaining valence electrons can be saturated by one axial and two bridging ligand halogen atoms such as chlorine or bromine . Technetium forms a variety of coordination complexes with organic ligands. Many have been well-investigated because of their relevance to nuclear medicine . Technetium forms a variety of compounds with Tc–C bonds, i.e. organotechnetium complexes. Prominent members of this class are complexes with CO, arene, and cyclopentadienyl ligands. The binary carbonyl Tc 2 (CO) 10
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#17328528575794216-492: The protagonist TC Televisión , Ecuador, a TV network Music [ edit ] TC Smith , American singer, for TCR Tom Constanten (born 1944), American musician from the Grateful Dead Top Combine , a Mandopop boy band TC (musician) , a British drum and bass producer and DJ Games [ edit ] Transcendental Chess X3: Terran Conflict , a PC game T.C., an era designation in
4284-416: The reaction Mo(p,2n) Tc was demonstrated in 1971. The recent shortages of medical technetium-99m reignited the interest in its production by proton bombardment of isotopically enriched (>99.5%) molybdenum-100 targets. Other techniques are being investigated for obtaining molybdenum-99 from molybdenum-100 via (n,2n) or (γ,n) reactions in particle accelerators. Technetium-99m ("m" indicates that this
4352-682: The region where Walter Noddack's family originated). This name caused significant resentment in the scientific community, because it was interpreted as referring to a series of victories of the German army over the Russian army in the Masuria region during World War I; as the Noddacks remained in their academic positions while the Nazis were in power, suspicions and hostility against their claim for discovering element 43 continued. The group bombarded columbite with
4420-458: The spectral types S-, M-, and N display a spectral absorption line indicating the presence of technetium. These red giants are known informally as technetium stars . In contrast to the rare natural occurrence, bulk quantities of technetium-99 are produced each year from spent nuclear fuel rods , which contain various fission products. The fission of a gram of uranium-235 in nuclear reactors yields 27 mg of technetium-99, giving technetium
4488-428: The structure of either trichloride phase. Instead it has the structure of molybdenum tribromide , consisting of chains of confacial octahedra with alternating short and long Tc—Tc contacts. TcI 3 has the same structure as the high temperature phase of TiI 3 , featuring chains of confacial octahedra with equal Tc—Tc contacts. Several anionic technetium halides are known. The binary tetrahalides can be converted to
4556-409: The technetium-99m used in medical work is produced by irradiating dedicated highly enriched uranium targets in a reactor, extracting molybdenum-99 from the targets in reprocessing facilities, and recovering at the diagnostic center the technetium-99m produced upon decay of molybdenum-99. Molybdenum-99 in the form of molybdate MoO 4 is adsorbed onto acid alumina ( Al 2 O 3 ) in
4624-414: Was released into the environment during atmospheric nuclear tests . The amount of technetium-99 from nuclear reactors released into the environment up to 1986 is on the order of 1000 TBq (about 1600 kg), primarily by nuclear fuel reprocessing ; most of this was discharged into the sea. Reprocessing methods have reduced emissions since then, but as of 2005 the primary release of technetium-99 into
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