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Gadolinium

Gadolinium is a chemical element with the symbol Gd and atomic number 64. Gadolinium is a silvery-white metal when oxidation is removed. It is only slightly malleable and is a ductile rare-earth element. Gadolinium reacts with atmospheric oxygen or moisture slowly to form a black coating. Gadolinium below its Curie point of 20 °C (68 °F) is ferromagnetic, with an attraction to a magnetic field higher than that of nickel. Above this temperature it is the most paramagnetic element. It is found in nature only in an oxidized form. When separated, it usually has impurities of the other rare-earths because of their similar chemical properties.

Gadolinium, 64Gd
Gadolinium
Pronunciation/ˌɡædəˈlɪniəm/ (GAD-ə-LIN-ee-əm)
Appearancesilvery white
Standard atomic weight Ar°(Gd)
  • 157.25±0.03
  • 157.25±0.03 (abridged)[1]
Gadolinium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson


Gd

Cm
europiumgadoliniumterbium
Atomic number (Z)64
Groupf-block groups (no number)
Periodperiod 6
Block  f-block
Electron configuration[Xe] 4f7 5d1 6s2
Electrons per shell2, 8, 18, 25, 9, 2
Physical properties
Phase at STPsolid
Melting point1585 K ​(1312 °C, ​2394 °F)
Boiling point3273 K ​(3000 °C, ​5432 °F)
Density (near r.t.)7.90 g/cm3
when liquid (at m.p.)7.4 g/cm3
Heat of fusion10.05 kJ/mol
Heat of vaporization301.3 kJ/mol
Molar heat capacity37.03 J/(mol·K)
Vapor pressure (calculated)
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1836 2028 2267 2573 2976 3535
Atomic properties
Oxidation states0,[2] +1, +2, +3 (a mildly basic oxide)
ElectronegativityPauling scale: 1.20
Ionization energies
  • 1st: 593.4 kJ/mol
  • 2nd: 1170 kJ/mol
  • 3rd: 1990 kJ/mol
Atomic radiusempirical: 180 pm
Covalent radius196±6 pm
Spectral lines of gadolinium
Other properties
Natural occurrenceprimordial
Crystal structurehexagonal close-packed (hcp)
Speed of sound thin rod2680 m/s (at 20 °C)
Thermal expansionα poly: 9.4 µm/(m⋅K) (at 100 °C)
Thermal conductivity10.6 W/(m⋅K)
Electrical resistivityα, poly: 1.310 µΩ⋅m
Magnetic orderingferromagneticparamagnetic transition at 293.4 K
Molar magnetic susceptibility+755000.0×10−6 cm3/mol (300.6 K)[3]
Young's modulusα form: 54.8 GPa
Shear modulusα form: 21.8 GPa
Bulk modulusα form: 37.9 GPa
Poisson ratioα form: 0.259
Vickers hardness510–950 MPa
CAS Number7440-54-2
History
Namingafter the mineral Gadolinite (itself named after Johan Gadolin)
DiscoveryJean Charles Galissard de Marignac (1880)
First isolationLecoq de Boisbaudran (1886)
Main isotopes of gadolinium
Abun­dance Half-life (t1/2) Decay mode Pro­duct
148Gd syn 75 y α 144Sm
150Gd syn 1.8×106 y α 146Sm
152Gd 0.20% 1.08×1014 y α 148Sm
154Gd 2.18% stable
155Gd 14.80% stable
156Gd 20.47% stable
157Gd 15.65% stable
158Gd 24.84% stable
160Gd 21.86% stable
 Category: Gadolinium
| references

Gadolinium was discovered in 1880 by Jean Charles de Marignac, who detected its oxide by using spectroscopy. It is named after the mineral gadolinite, one of the minerals in which gadolinium is found, itself named for the Finnish chemist Johan Gadolin. Pure gadolinium was first isolated by the chemist Paul-Émile Lecoq de Boisbaudran around 1886.

Gadolinium possesses unusual metallurgical properties, to the extent that as little as 1% of gadolinium can significantly improve the workability and resistance to oxidation at high temperatures of iron, chromium, and related metals. Gadolinium as a metal or a salt absorbs neutrons and is, therefore, used sometimes for shielding in neutron radiography and in nuclear reactors.

Like most of the rare earths, gadolinium forms trivalent ions with fluorescent properties, and salts of gadolinium(III) are used as phosphors in various applications.

Gadolinium(III) ions in water-soluble salts are highly toxic to mammals. However, chelated gadolinium(III) compounds prevent the gadolinium(III) from being exposed to the organism and the majority is excreted by healthy[4] kidneys before it can deposit in tissues. Because of its paramagnetic properties, solutions of chelated organic gadolinium complexes are used as intravenously administered gadolinium-based MRI contrast agents in medical magnetic resonance imaging. Varying amounts deposit in tissues of the brain, cardiac muscle, kidney, other organs and the skin, mainly depending on kidney function, structure of the chelates (linear or macrocyclic) and the dose administered.

Characteristics

 
A sample of gadolinium metal

Physical properties

Gadolinium is the eighth member of the lanthanide series. In the periodic table, it appears between the elements europium to its left and terbium to its right, and above the actinide curium. It is a silvery-white, malleable, ductile rare-earth element. Its 64 electrons are arranged in the configuration of [Xe]4f75d16s2, of which the ten 4f, 5d, and 6s electrons are valence.

Like most other metals in the lanthanide series, gadolinium usually uses three electrons as valence electrons, as afterward the remaining 4f electrons are too strongly bound: this is because the 4f orbitals penetrate the most through the inert xenon core of electrons to the nucleus, followed by 5d and 6s, and this increases with higher ionic charge. It crystallizes in the hexagonal close-packed α-form at room temperature, but, when heated to temperatures above 1,235 °C (2,255 °F), it transforms into its β-form, which has a body-centered cubic structure.[5]

The isotope gadolinium-157 has the highest thermal-neutron capture cross-section among any stable nuclide: about 259,000 barns. Only xenon-135 has a higher capture cross-section, about 2.0 million barns, but this isotope is radioactive.[6]

Gadolinium is believed to be ferromagnetic at temperatures below 20 °C (68 °F)[7] and is strongly paramagnetic above this temperature. There is evidence that gadolinium is a helical antiferromagnetic, rather than a ferromagnetic, below 20 °C (68 °F).[8] Gadolinium demonstrates a magnetocaloric effect whereby its temperature increases when it enters a magnetic field and decreases when it leaves the magnetic field. The temperature is lowered to 5 °C (41 °F) for the gadolinium alloy Gd85Er15, and this effect is considerably stronger for the alloy Gd5(Si2Ge2), but at a much lower temperature (<85 K (−188.2 °C; −306.7 °F)).[9] A significant magnetocaloric effect is observed at higher temperatures, up to about 300 kelvins, in the compounds Gd5(SixGe1−x)4.[10]

Individual gadolinium atoms can be isolated by encapsulating them into fullerene molecules, where they can be visualized with a transmission electron microscope.[11] Individual Gd atoms and small Gd clusters can be incorporated into carbon nanotubes.[12]

Chemical properties

Gadolinium combines with most elements to form Gd(III) derivatives. It also combines with nitrogen, carbon, sulfur, phosphorus, boron, selenium, silicon, and arsenic at elevated temperatures, forming binary compounds.[13]

Unlike the other rare-earth elements, metallic gadolinium is relatively stable in dry air. However, it tarnishes quickly in moist air, forming a loosely-adhering gadolinium(III) oxide (Gd2O3):

4 Gd + 3 O2 → 2 Gd2O3,

which spalls off, exposing more surface to oxidation.

Gadolinium is a strong reducing agent, which reduces oxides of several metals into their elements. Gadolinium is quite electropositive and reacts slowly with cold water and quite quickly with hot water to form gadolinium hydroxide:

2 Gd + 6 H2O → 2 Gd(OH)3 + 3 H2.

Gadolinium metal is attacked readily by dilute sulfuric acid to form solutions containing the colorless Gd(III) ions, which exist as [Gd(H2O)9]3+ complexes:[14]

2 Gd + 3 H2SO4 + 18 H2O → 2 [Gd(H2O)9]3+ + 3 SO2−
4
+ 3 H2.

Gadolinium metal reacts with the halogens (X2) at temperature about 200 °C (392 °F):[citation needed]

2 Gd + 3 X2 → 2 GdX3.

Chemical compounds

In the great majority of its compounds, like many rare-earth metals, gadolinium adopts the oxidation state +3. However, gadolinium can be found on rare occasions in the 0, +1 and +2 oxidation states. All four trihalides are known. All are white, except for the iodide, which is yellow. Most commonly encountered of the halides is gadolinium(III) chloride (GdCl3). The oxide dissolves in acids to give the salts, such as gadolinium(III) nitrate.

Gadolinium(III), like most lanthanide ions, forms complexes with high coordination numbers. This tendency is illustrated by the use of the chelating agent DOTA, an octadentate ligand. Salts of [Gd(DOTA)] are useful in magnetic resonance imaging. A variety of related chelate complexes have been developed, including gadodiamide.

Reduced gadolinium compounds are known, especially in the solid state. Gadolinium(II) halides are obtained by heating Gd(III) halides in presence of metallic Gd in tantalum containers. Gadolinium also form sesquichloride Gd2Cl3, which can be further reduced to GdCl by annealing at 800 °C (1,470 °F). This gadolinium(I) chloride forms platelets with layered graphite-like structure.[15]

Isotopes

Naturally occurring gadolinium is composed of six stable isotopes, 154Gd, 155Gd, 156Gd, 157Gd, 158Gd and 160Gd, and one radioisotope, 152Gd, with the isotope 158Gd being the most abundant (24.8% natural abundance). The predicted double beta decay of 160Gd has never been observed (an experimental lower limit on its half-life of more than 1.3×1021 years has been measured[16]).

Thirty-three radioisotopes of gadolinium have been observed, with the most stable being 152Gd (naturally occurring), with a half-life of about 1.08×1014 years, and 150Gd, with a half-life of 1.79×106 years. All of the remaining radioactive isotopes have half-lives of less than 75 years. The majority of these have half-lives of less than 25 seconds. Gadolinium isotopes have four metastable isomers, with the most stable being 143mGd (t1/2= 110 seconds), 145mGd (t1/2= 85 seconds) and 141mGd (t1/2= 24.5 seconds).

The isotopes with atomic masses lower than the most abundant stable isotope, 158Gd, primarily decay by electron capture to isotopes of europium. At higher atomic masses, the primary decay mode is beta decay, and the primary products are isotopes of terbium.

History

Gadolinium is named after the mineral gadolinite, in turn named after Finnish chemist and geologist Johan Gadolin.[5] In 1880, the Swiss chemist Jean Charles Galissard de Marignac observed the spectroscopic lines from gadolinium in samples of gadolinite (which actually contains relatively little gadolinium, but enough to show a spectrum) and in the separate mineral cerite. The latter mineral proved to contain far more of the element with the new spectral line. De Marignac eventually separated a mineral oxide from cerite, which he realized was the oxide of this new element. He named the oxide "gadolinia". Because he realized that "gadolinia" was the oxide of a new element, he is credited with the discovery of gadolinium. The French chemist Paul-Émile Lecoq de Boisbaudran carried out the separation of gadolinium metal from gadolinia in 1886.[17][18][19][20]

Occurrence

 
Gadolinite

Gadolinium is a constituent in many minerals such as monazite and bastnäsite. The metal is too reactive to exist naturally. Paradoxically, as noted above, the mineral gadolinite actually contains only traces of this element. The abundance in the Earth's crust is about 6.2 mg/kg.[5] The main mining areas are in China, the US, Brazil, Sri Lanka, India, and Australia with reserves expected to exceed one million tonnes. World production of pure gadolinium is about 400 tonnes per year. The only known mineral with essential gadolinium, lepersonnite-(Gd), is very rare.[21][22]

Production

Gadolinium is produced both from monazite and bastnäsite.

  1. Crushed minerals are extracted with hydrochloric acid or sulfuric acid, which converts the insoluble oxides into soluble chlorides or sulfates.
  2. The acidic filtrates are partially neutralized with caustic soda to pH 3–4. Thorium precipitates as its hydroxide, and is then removed.
  3. The remaining solution is treated with ammonium oxalate to convert rare earths into their insoluble oxalates. The oxalates are converted to oxides by heating.
  4. The oxides are dissolved in nitric acid that excludes one of the main components, cerium, whose oxide is insoluble in HNO3.
  5. The solution is treated with magnesium nitrate to produce a crystallized mixture of double salts of gadolinium, samarium and europium.
  6. The salts are separated by ion exchange chromatography.
  7. The rare-earth ions are then selectively washed out by a suitable complexing agent.[5]

Gadolinium metal is obtained from its oxide or salts by heating it with calcium at 1,450 °C (2,640 °F) in an argon atmosphere. Sponge gadolinium can be produced by reducing molten GdCl3 with an appropriate metal at temperatures below 1,312 °C (2,394 °F) (the melting point of Gd) at reduced pressure.[5]

Applications

Gadolinium has no large-scale applications, but it has a variety of specialized uses.

Because 157Gd has a high neutron cross-section, it is used to target tumors in neutron therapy. This element is effective for use with neutron radiography and in shielding of nuclear reactors. It is used as a secondary, emergency shut-down measure in some nuclear reactors, particularly of the CANDU reactor type.[5] Gadolinium is also used in nuclear marine propulsion systems as a burnable poison.

Gadolinium possesses unusual metallurgic properties, with as little as 1% of gadolinium improving the workability and resistance of iron, chromium, and related alloys to high temperatures and oxidation.[23]

Gadolinium is paramagnetic at room temperature, with a ferromagnetic Curie point of 20 °C (68 °F).[7] Paramagnetic ions, such as gadolinium, enhance nuclear relaxation rates, making gadolinium useful for magnetic resonance imaging (MRI). Solutions of organic gadolinium complexes and gadolinium compounds are used as intravenous MRI contrast agent to enhance images in medical magnetic resonance imaging and magnetic resonance angiography (MRA) procedures. Magnevist is the most widespread example.[24][25] Nanotubes packed with gadolinium, called "gadonanotubes", are 40 times more effective than the usual gadolinium contrast agent.[26] Traditional gadolinium-based contrast agents are un-targeted, generally distributing throughout the body after injection, but will not cross the intact blood–brain barrier. Brain tumors, and other disorders that degrade the blood-brain barrier, allow these agents to penetrate into the brain and facilitate their detection by contrast-enhanced MRI. Similarly, delayed gadolinium-enhanced magnetic resonance imaging of cartilage uses an ionic compound agent, originally Magnevist, that is excluded from healthy cartilage based on electrostatic repulsion but will enter proteoglycan-depleted cartilage in diseases such as osteoarthritis.

Gadolinium as a phosphor is also used in other imaging. In X-ray systems gadolinium is contained in the phosphor layer, suspended in a polymer matrix at the detector. Terbium-doped gadolinium oxysulfide (Gd2O2S:Tb) at the phosphor layer converts the X-rays released from the source into light. This material emits green light at 540 nm due to the presence of Tb3+, which is very useful for enhancing the imaging quality. The energy conversion of Gd is up to 20%, which means that 1/5 of the X-ray energy striking the phosphor layer can be converted into visible photons. Gadolinium oxyorthosilicate (Gd2SiO5, GSO; usually doped by 0.1–1.0% of Ce) is a single crystal that is used as a scintillator in medical imaging such as positron emission tomography or for detecting neutrons.[27]

Gadolinium compounds are also used for making green phosphors for color TV tubes.[28]

Gadolinium-153 is produced in a nuclear reactor from elemental europium or enriched gadolinium targets. It has a half-life of 240±10 days and emits gamma radiation with strong peaks at 41 keV and 102 keV. It is used in many quality-assurance applications, such as line sources and calibration phantoms, to ensure that nuclear-medicine imaging systems operate correctly and produce useful images of radioisotope distribution inside the patient.[29] It is also used as a gamma-ray source in X-ray absorption measurements or in bone density gauges for osteoporosis screening, as well as in the Lixiscope portable X-ray imaging system.[30]

Gadolinium is used for making gadolinium yttrium garnet (Gd:Y3Al5O12); it has microwave applications and is used in fabrication of various optical components and as substrate material for magneto-optical films.[citation needed]

Gadolinium gallium garnet (GGG, Gd3Ga5O12) was used for imitation diamonds and for computer bubble memory.[31]

Gadolinium can also serve as an electrolyte in solid oxide fuel cells (SOFCs). Using gadolinium as a dopant for materials like cerium oxide (in the form of gadolinium-doped ceria) creates an electrolyte with both high ionic conductivity and low operating temperatures, which are optimal for cost-effective production of fuel cells.

Research is being conducted on magnetic refrigeration near room temperature, which could provide significant efficiency and environmental advantages over conventional refrigeration methods. Gadolinium-based materials, such as Gd5(SixGe1−x)4, are currently the most promising materials, owing to their high Curie temperature and giant magnetocaloric effect. Pure Gd itself exhibits a large magnetocaloric effect near its Curie temperature of 20 °C (68 °F), and this has sparked great interest into producing Gd alloys with a larger effect and tunable Curie temperature. In Gd5(SixGe1−x)4, Si and Ge compositions can be varied to adjust the Curie temperature. This technology is still very early in development, and significant material improvements still need to be made before it is commercially viable.[10]

Physicists Mark Vagins and John Beacom, of the Japanese Super Kamiokande, theorized that gadolinium may facilitate neutrino detection when it is added to very high-purity water in the tank.[32]

Gadolinium barium copper oxide (GdBCO) has been researched for its superconducting properties[33][34][35] with applications in superconducting motors or generators - for example in a wind turbine.[36] It can be manufactured in the same way as the most widely researched cuprate high temperature superconductor, Yttrium barium copper oxide (YBCO) and uses an analogous chemical composition (GdBa2Cu3O7−δ ).[37] Most notably, it was used by the Bulk Superconductivity Group from the University of Cambridge in 2014 to set a new world record for the highest trapped magnetic field in a bulk high temperature superconductor, with a field of 17.6T being trapped within two GdBCO bulks.[38][39]

Safety

Gadolinium
Hazards
GHS labelling:
 
Danger
H261
P231+P232, P422[40]
NFPA 704 (fire diamond)
0
0
1

As a free ion, gadolinium is reported often to be highly toxic, but MRI contrast agents are chelated compounds and are considered safe enough to be used in most persons. The toxicity of free gadolinium ions in animals is due to interference with a number of calcium-ion channel dependent processes. The 50% lethal dose is about 0.34 mmol/kg (IV, mouse)[41] or 100–200 mg/kg. Toxicity studies in rodents show that chelation of gadolinium (which also improves its solubility) decreases its toxicity with regard to the free ion by a factor of 31 (i.e., the lethal dose for the Gd-chelate increases by 31 times).[42][43][44] It is believed therefore that clinical toxicity of gadolinium-based contrast agents (GBCAs[45]) in humans will depend on the strength of the chelating agent; however this research is still not complete.[when?] About a dozen different Gd-chelated agents have been approved as MRI contrast agents around the world.[46][47][48]

In patients with kidney failure, there is a risk of a rare but serious illness called nephrogenic systemic fibrosis (NSF)[49] that is caused by the use of gadolinium based contrast agents. The disease resembles scleromyxedema and to some extent scleroderma. It may occur months after a contrast agent has been injected. Its association with gadolinium and not the carrier molecule is confirmed by its occurrence with various contrast materials in which gadolinium is carried by very different carrier molecules. Due to this, it is not recommended to use these agents for any individual with end-stage kidney failure as they will require emergent dialysis. Similar but not identical symptoms to NSF may occur in subjects with normal or near-normal renal function within hours to 2 months following the administration of GBCAs; the name "gadolinium deposition disease" (GDD) has been proposed for this condition, which occurs in the absence of pre-existent disease or subsequently developed disease of an alternate known process. A 2016 study reported numerous anecdotal cases of GDD.[50] However, in that study, participants were recruited from online support groups for subjects self-identified as having gadolinium toxicity, and no relevant medical history or data were collected. There have yet to be definitive scientific studies proving the existence of the condition.

Included in the current guidelines from the Canadian Association of Radiologists[51] are that dialysis patients should only receive gadolinium agents where essential and that they should receive dialysis after the exam. If a contrast-enhanced MRI must be performed on a dialysis patient, it is recommended that certain high-risk contrast agents be avoided but not that a lower dose be considered.[51] The American College of Radiology recommends that contrast-enhanced MRI examinations be performed as closely before dialysis as possible as a precautionary measure, although this has not been proven to reduce the likelihood of developing NSF.[52] The FDA recommends that potential for gadolinium retention be considered when choosing the type of GBCA used in patients requiring multiple lifetime doses, pregnant women, children, and patients with inflammatory conditions.[53]

Anaphylactoid reactions are rare, occurring in approximately 0.03–0.1%.[54]

Long-term environmental impacts of gadolinium contamination due to human usage is a topic of ongoing research.[55][56]

Biological role

Gadolinium has no known native biological role, but its compounds are used as research tools in biomedicine. Gd3+ compounds are components of MRI contrast agents.[57] It is used in various ion channel electrophysiology experiments to block sodium leak channels and stretch activated ion channels.[58] Gadolinium has recently been used to measure the distance between two points in a protein via electron paramagnetic resonance, something that gadolinium is especially amenable to thanks to EPR sensitivity at w-band (95 GHz) frequencies.[59]

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External links

  • (series of images at MedPix website)
  • It's Elemental – Gadolinium
  • Abdominal MR imaging: important considerations for evaluation of gadolinium enhancement Rafael O.P. de Campos, Vasco Herédia, Ersan Altun, Richard C. Semelka, Department of Radiology University of North Carolina Hospitals Chapel Hill
  • Inside Japan’s Super Kamiokande 360 degree tour including details on adding Gadolinium to the pure water to aid in studying neutrinos

gadolinium, chemical, element, with, symbol, atomic, number, silvery, white, metal, when, oxidation, removed, only, slightly, malleable, ductile, rare, earth, element, reacts, with, atmospheric, oxygen, moisture, slowly, form, black, coating, below, curie, poi. Gadolinium is a chemical element with the symbol Gd and atomic number 64 Gadolinium is a silvery white metal when oxidation is removed It is only slightly malleable and is a ductile rare earth element Gadolinium reacts with atmospheric oxygen or moisture slowly to form a black coating Gadolinium below its Curie point of 20 C 68 F is ferromagnetic with an attraction to a magnetic field higher than that of nickel Above this temperature it is the most paramagnetic element It is found in nature only in an oxidized form When separated it usually has impurities of the other rare earths because of their similar chemical properties Gadolinium 64GdGadoliniumPronunciation ˌ ɡ ae d e ˈ l ɪ n i e m wbr GAD e LIN ee em Appearancesilvery whiteStandard atomic weightAr Gd 157 25 0 03157 25 0 03 abridged 1 Gadolinium in the periodic tableHydrogen HeliumLithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine NeonSodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine ArgonPotassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine KryptonRubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine XenonCaesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury element Thallium Lead Bismuth Polonium Astatine RadonFrancium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Gd Cmeuropium gadolinium terbiumAtomic number Z 64Groupf block groups no number Periodperiod 6Block f blockElectron configuration Xe 4f7 5d1 6s2Electrons per shell2 8 18 25 9 2Physical propertiesPhase at STPsolidMelting point1585 K 1312 C 2394 F Boiling point3273 K 3000 C 5432 F Density near r t 7 90 g cm3when liquid at m p 7 4 g cm3Heat of fusion10 05 kJ molHeat of vaporization301 3 kJ molMolar heat capacity37 03 J mol K Vapor pressure calculated P Pa 1 10 100 1 k 10 k 100 kat T K 1836 2028 2267 2573 2976 3535Atomic propertiesOxidation states0 2 1 2 3 a mildly basic oxide ElectronegativityPauling scale 1 20Ionization energies1st 593 4 kJ mol2nd 1170 kJ mol3rd 1990 kJ molAtomic radiusempirical 180 pmCovalent radius196 6 pmSpectral lines of gadoliniumOther propertiesNatural occurrenceprimordialCrystal structure hexagonal close packed hcp Speed of sound thin rod2680 m s at 20 C Thermal expansiona poly 9 4 µm m K at 100 C Thermal conductivity10 6 W m K Electrical resistivitya poly 1 310 µW mMagnetic orderingferromagnetic paramagnetic transition at 293 4 KMolar magnetic susceptibility 755000 0 10 6 cm3 mol 300 6 K 3 Young s modulusa form 54 8 GPaShear modulusa form 21 8 GPaBulk modulusa form 37 9 GPaPoisson ratioa form 0 259Vickers hardness510 950 MPaCAS Number7440 54 2HistoryNamingafter the mineral Gadolinite itself named after Johan Gadolin DiscoveryJean Charles Galissard de Marignac 1880 First isolationLecoq de Boisbaudran 1886 Main isotopes of gadoliniumAbun dance Half life t1 2 Decay mode Pro duct148Gd syn 75 y a 144Sm150Gd syn 1 8 106 y a 146Sm152Gd 0 20 1 08 1014 y a 148Sm154Gd 2 18 stable155Gd 14 80 stable156Gd 20 47 stable157Gd 15 65 stable158Gd 24 84 stable160Gd 21 86 stable Category Gadoliniumviewtalkedit referencesGadolinium was discovered in 1880 by Jean Charles de Marignac who detected its oxide by using spectroscopy It is named after the mineral gadolinite one of the minerals in which gadolinium is found itself named for the Finnish chemist Johan Gadolin Pure gadolinium was first isolated by the chemist Paul Emile Lecoq de Boisbaudran around 1886 Gadolinium possesses unusual metallurgical properties to the extent that as little as 1 of gadolinium can significantly improve the workability and resistance to oxidation at high temperatures of iron chromium and related metals Gadolinium as a metal or a salt absorbs neutrons and is therefore used sometimes for shielding in neutron radiography and in nuclear reactors Like most of the rare earths gadolinium forms trivalent ions with fluorescent properties and salts of gadolinium III are used as phosphors in various applications Gadolinium III ions in water soluble salts are highly toxic to mammals However chelated gadolinium III compounds prevent the gadolinium III from being exposed to the organism and the majority is excreted by healthy 4 kidneys before it can deposit in tissues Because of its paramagnetic properties solutions of chelated organic gadolinium complexes are used as intravenously administered gadolinium based MRI contrast agents in medical magnetic resonance imaging Varying amounts deposit in tissues of the brain cardiac muscle kidney other organs and the skin mainly depending on kidney function structure of the chelates linear or macrocyclic and the dose administered Contents 1 Characteristics 1 1 Physical properties 1 2 Chemical properties 1 2 1 Chemical compounds 1 3 Isotopes 2 History 3 Occurrence 4 Production 5 Applications 6 Safety 7 Biological role 8 References 9 External linksCharacteristics Edit A sample of gadolinium metal Physical properties Edit Gadolinium is the eighth member of the lanthanide series In the periodic table it appears between the elements europium to its left and terbium to its right and above the actinide curium It is a silvery white malleable ductile rare earth element Its 64 electrons are arranged in the configuration of Xe 4f75d16s2 of which the ten 4f 5d and 6s electrons are valence Like most other metals in the lanthanide series gadolinium usually uses three electrons as valence electrons as afterward the remaining 4f electrons are too strongly bound this is because the 4f orbitals penetrate the most through the inert xenon core of electrons to the nucleus followed by 5d and 6s and this increases with higher ionic charge It crystallizes in the hexagonal close packed a form at room temperature but when heated to temperatures above 1 235 C 2 255 F it transforms into its b form which has a body centered cubic structure 5 The isotope gadolinium 157 has the highest thermal neutron capture cross section among any stable nuclide about 259 000 barns Only xenon 135 has a higher capture cross section about 2 0 million barns but this isotope is radioactive 6 Gadolinium is believed to be ferromagnetic at temperatures below 20 C 68 F 7 and is strongly paramagnetic above this temperature There is evidence that gadolinium is a helical antiferromagnetic rather than a ferromagnetic below 20 C 68 F 8 Gadolinium demonstrates a magnetocaloric effect whereby its temperature increases when it enters a magnetic field and decreases when it leaves the magnetic field The temperature is lowered to 5 C 41 F for the gadolinium alloy Gd85Er15 and this effect is considerably stronger for the alloy Gd5 Si2Ge2 but at a much lower temperature lt 85 K 188 2 C 306 7 F 9 A significant magnetocaloric effect is observed at higher temperatures up to about 300 kelvins in the compounds Gd5 SixGe1 x 4 10 Individual gadolinium atoms can be isolated by encapsulating them into fullerene molecules where they can be visualized with a transmission electron microscope 11 Individual Gd atoms and small Gd clusters can be incorporated into carbon nanotubes 12 Chemical properties Edit See also Category Gadolinium compounds Gadolinium combines with most elements to form Gd III derivatives It also combines with nitrogen carbon sulfur phosphorus boron selenium silicon and arsenic at elevated temperatures forming binary compounds 13 Unlike the other rare earth elements metallic gadolinium is relatively stable in dry air However it tarnishes quickly in moist air forming a loosely adhering gadolinium III oxide Gd2O3 4 Gd 3 O2 2 Gd2O3 which spalls off exposing more surface to oxidation Gadolinium is a strong reducing agent which reduces oxides of several metals into their elements Gadolinium is quite electropositive and reacts slowly with cold water and quite quickly with hot water to form gadolinium hydroxide 2 Gd 6 H2O 2 Gd OH 3 3 H2 Gadolinium metal is attacked readily by dilute sulfuric acid to form solutions containing the colorless Gd III ions which exist as Gd H2O 9 3 complexes 14 2 Gd 3 H2SO4 18 H2O 2 Gd H2O 9 3 3 SO2 4 3 H2 Gadolinium metal reacts with the halogens X2 at temperature about 200 C 392 F citation needed 2 Gd 3 X2 2 GdX3 Chemical compounds Edit In the great majority of its compounds like many rare earth metals gadolinium adopts the oxidation state 3 However gadolinium can be found on rare occasions in the 0 1 and 2 oxidation states All four trihalides are known All are white except for the iodide which is yellow Most commonly encountered of the halides is gadolinium III chloride GdCl3 The oxide dissolves in acids to give the salts such as gadolinium III nitrate Gadolinium III like most lanthanide ions forms complexes with high coordination numbers This tendency is illustrated by the use of the chelating agent DOTA an octadentate ligand Salts of Gd DOTA are useful in magnetic resonance imaging A variety of related chelate complexes have been developed including gadodiamide Reduced gadolinium compounds are known especially in the solid state Gadolinium II halides are obtained by heating Gd III halides in presence of metallic Gd in tantalum containers Gadolinium also form sesquichloride Gd2Cl3 which can be further reduced to GdCl by annealing at 800 C 1 470 F This gadolinium I chloride forms platelets with layered graphite like structure 15 Isotopes Edit Main article Isotopes of gadolinium Naturally occurring gadolinium is composed of six stable isotopes 154Gd 155Gd 156Gd 157Gd 158Gd and 160Gd and one radioisotope 152Gd with the isotope 158Gd being the most abundant 24 8 natural abundance The predicted double beta decay of 160Gd has never been observed an experimental lower limit on its half life of more than 1 3 1021 years has been measured 16 Thirty three radioisotopes of gadolinium have been observed with the most stable being 152Gd naturally occurring with a half life of about 1 08 1014 years and 150Gd with a half life of 1 79 106 years All of the remaining radioactive isotopes have half lives of less than 75 years The majority of these have half lives of less than 25 seconds Gadolinium isotopes have four metastable isomers with the most stable being 143mGd t1 2 110 seconds 145mGd t1 2 85 seconds and 141mGd t1 2 24 5 seconds The isotopes with atomic masses lower than the most abundant stable isotope 158Gd primarily decay by electron capture to isotopes of europium At higher atomic masses the primary decay mode is beta decay and the primary products are isotopes of terbium History EditGadolinium is named after the mineral gadolinite in turn named after Finnish chemist and geologist Johan Gadolin 5 In 1880 the Swiss chemist Jean Charles Galissard de Marignac observed the spectroscopic lines from gadolinium in samples of gadolinite which actually contains relatively little gadolinium but enough to show a spectrum and in the separate mineral cerite The latter mineral proved to contain far more of the element with the new spectral line De Marignac eventually separated a mineral oxide from cerite which he realized was the oxide of this new element He named the oxide gadolinia Because he realized that gadolinia was the oxide of a new element he is credited with the discovery of gadolinium The French chemist Paul Emile Lecoq de Boisbaudran carried out the separation of gadolinium metal from gadolinia in 1886 17 18 19 20 Occurrence Edit Gadolinite Gadolinium is a constituent in many minerals such as monazite and bastnasite The metal is too reactive to exist naturally Paradoxically as noted above the mineral gadolinite actually contains only traces of this element The abundance in the Earth s crust is about 6 2 mg kg 5 The main mining areas are in China the US Brazil Sri Lanka India and Australia with reserves expected to exceed one million tonnes World production of pure gadolinium is about 400 tonnes per year The only known mineral with essential gadolinium lepersonnite Gd is very rare 21 22 Production EditGadolinium is produced both from monazite and bastnasite Crushed minerals are extracted with hydrochloric acid or sulfuric acid which converts the insoluble oxides into soluble chlorides or sulfates The acidic filtrates are partially neutralized with caustic soda to pH 3 4 Thorium precipitates as its hydroxide and is then removed The remaining solution is treated with ammonium oxalate to convert rare earths into their insoluble oxalates The oxalates are converted to oxides by heating The oxides are dissolved in nitric acid that excludes one of the main components cerium whose oxide is insoluble in HNO3 The solution is treated with magnesium nitrate to produce a crystallized mixture of double salts of gadolinium samarium and europium The salts are separated by ion exchange chromatography The rare earth ions are then selectively washed out by a suitable complexing agent 5 Gadolinium metal is obtained from its oxide or salts by heating it with calcium at 1 450 C 2 640 F in an argon atmosphere Sponge gadolinium can be produced by reducing molten GdCl3 with an appropriate metal at temperatures below 1 312 C 2 394 F the melting point of Gd at reduced pressure 5 Applications EditGadolinium has no large scale applications but it has a variety of specialized uses Because 157Gd has a high neutron cross section it is used to target tumors in neutron therapy This element is effective for use with neutron radiography and in shielding of nuclear reactors It is used as a secondary emergency shut down measure in some nuclear reactors particularly of the CANDU reactor type 5 Gadolinium is also used in nuclear marine propulsion systems as a burnable poison Gadolinium possesses unusual metallurgic properties with as little as 1 of gadolinium improving the workability and resistance of iron chromium and related alloys to high temperatures and oxidation 23 Gadolinium is paramagnetic at room temperature with a ferromagnetic Curie point of 20 C 68 F 7 Paramagnetic ions such as gadolinium enhance nuclear relaxation rates making gadolinium useful for magnetic resonance imaging MRI Solutions of organic gadolinium complexes and gadolinium compounds are used as intravenous MRI contrast agent to enhance images in medical magnetic resonance imaging and magnetic resonance angiography MRA procedures Magnevist is the most widespread example 24 25 Nanotubes packed with gadolinium called gadonanotubes are 40 times more effective than the usual gadolinium contrast agent 26 Traditional gadolinium based contrast agents are un targeted generally distributing throughout the body after injection but will not cross the intact blood brain barrier Brain tumors and other disorders that degrade the blood brain barrier allow these agents to penetrate into the brain and facilitate their detection by contrast enhanced MRI Similarly delayed gadolinium enhanced magnetic resonance imaging of cartilage uses an ionic compound agent originally Magnevist that is excluded from healthy cartilage based on electrostatic repulsion but will enter proteoglycan depleted cartilage in diseases such as osteoarthritis Gadolinium as a phosphor is also used in other imaging In X ray systems gadolinium is contained in the phosphor layer suspended in a polymer matrix at the detector Terbium doped gadolinium oxysulfide Gd2O2S Tb at the phosphor layer converts the X rays released from the source into light This material emits green light at 540 nm due to the presence of Tb3 which is very useful for enhancing the imaging quality The energy conversion of Gd is up to 20 which means that 1 5 of the X ray energy striking the phosphor layer can be converted into visible photons Gadolinium oxyorthosilicate Gd2SiO5 GSO usually doped by 0 1 1 0 of Ce is a single crystal that is used as a scintillator in medical imaging such as positron emission tomography or for detecting neutrons 27 Gadolinium compounds are also used for making green phosphors for color TV tubes 28 Gadolinium 153 is produced in a nuclear reactor from elemental europium or enriched gadolinium targets It has a half life of 240 10 days and emits gamma radiation with strong peaks at 41 keV and 102 keV It is used in many quality assurance applications such as line sources and calibration phantoms to ensure that nuclear medicine imaging systems operate correctly and produce useful images of radioisotope distribution inside the patient 29 It is also used as a gamma ray source in X ray absorption measurements or in bone density gauges for osteoporosis screening as well as in the Lixiscope portable X ray imaging system 30 Gadolinium is used for making gadolinium yttrium garnet Gd Y3Al5O12 it has microwave applications and is used in fabrication of various optical components and as substrate material for magneto optical films citation needed Gadolinium gallium garnet GGG Gd3Ga5O12 was used for imitation diamonds and for computer bubble memory 31 Gadolinium can also serve as an electrolyte in solid oxide fuel cells SOFCs Using gadolinium as a dopant for materials like cerium oxide in the form of gadolinium doped ceria creates an electrolyte with both high ionic conductivity and low operating temperatures which are optimal for cost effective production of fuel cells Research is being conducted on magnetic refrigeration near room temperature which could provide significant efficiency and environmental advantages over conventional refrigeration methods Gadolinium based materials such as Gd5 SixGe1 x 4 are currently the most promising materials owing to their high Curie temperature and giant magnetocaloric effect Pure Gd itself exhibits a large magnetocaloric effect near its Curie temperature of 20 C 68 F and this has sparked great interest into producing Gd alloys with a larger effect and tunable Curie temperature In Gd5 SixGe1 x 4 Si and Ge compositions can be varied to adjust the Curie temperature This technology is still very early in development and significant material improvements still need to be made before it is commercially viable 10 Physicists Mark Vagins and John Beacom of the Japanese Super Kamiokande theorized that gadolinium may facilitate neutrino detection when it is added to very high purity water in the tank 32 Gadolinium barium copper oxide GdBCO has been researched for its superconducting properties 33 34 35 with applications in superconducting motors or generators for example in a wind turbine 36 It can be manufactured in the same way as the most widely researched cuprate high temperature superconductor Yttrium barium copper oxide YBCO and uses an analogous chemical composition GdBa2Cu3O7 d 37 Most notably it was used by the Bulk Superconductivity Group from the University of Cambridge in 2014 to set a new world record for the highest trapped magnetic field in a bulk high temperature superconductor with a field of 17 6T being trapped within two GdBCO bulks 38 39 Safety EditMain articles MRI contrast agent and Nephrogenic systemic fibrosis Gadolinium HazardsGHS labelling Pictograms Signal word DangerHazard statements H261Precautionary statements P231 P232 P422 40 NFPA 704 fire diamond 001W As a free ion gadolinium is reported often to be highly toxic but MRI contrast agents are chelated compounds and are considered safe enough to be used in most persons The toxicity of free gadolinium ions in animals is due to interference with a number of calcium ion channel dependent processes The 50 lethal dose is about 0 34 mmol kg IV mouse 41 or 100 200 mg kg Toxicity studies in rodents show that chelation of gadolinium which also improves its solubility decreases its toxicity with regard to the free ion by a factor of 31 i e the lethal dose for the Gd chelate increases by 31 times 42 43 44 It is believed therefore that clinical toxicity of gadolinium based contrast agents GBCAs 45 in humans will depend on the strength of the chelating agent however this research is still not complete when About a dozen different Gd chelated agents have been approved as MRI contrast agents around the world 46 47 48 In patients with kidney failure there is a risk of a rare but serious illness called nephrogenic systemic fibrosis NSF 49 that is caused by the use of gadolinium based contrast agents The disease resembles scleromyxedema and to some extent scleroderma It may occur months after a contrast agent has been injected Its association with gadolinium and not the carrier molecule is confirmed by its occurrence with various contrast materials in which gadolinium is carried by very different carrier molecules Due to this it is not recommended to use these agents for any individual with end stage kidney failure as they will require emergent dialysis Similar but not identical symptoms to NSF may occur in subjects with normal or near normal renal function within hours to 2 months following the administration of GBCAs the name gadolinium deposition disease GDD has been proposed for this condition which occurs in the absence of pre existent disease or subsequently developed disease of an alternate known process A 2016 study reported numerous anecdotal cases of GDD 50 However in that study participants were recruited from online support groups for subjects self identified as having gadolinium toxicity and no relevant medical history or data were collected There have yet to be definitive scientific studies proving the existence of the condition Included in the current guidelines from the Canadian Association of Radiologists 51 are that dialysis patients should only receive gadolinium agents where essential and that they should receive dialysis after the exam If a contrast enhanced MRI must be performed on a dialysis patient it is recommended that certain high risk contrast agents be avoided but not that a lower dose be considered 51 The American College of Radiology recommends that contrast enhanced MRI examinations be performed as closely before dialysis as possible as a precautionary measure although this has not been proven to reduce the likelihood of developing NSF 52 The FDA recommends that potential for gadolinium retention be considered when choosing the type of GBCA used in patients requiring multiple lifetime doses pregnant women children and patients with inflammatory conditions 53 Anaphylactoid reactions are rare occurring in approximately 0 03 0 1 54 Long term environmental impacts of gadolinium contamination due to human usage is a topic of ongoing research 55 56 Biological role EditGadolinium has no known native biological role but its compounds are used as research tools in biomedicine Gd3 compounds are components of MRI contrast agents 57 It is used in various ion channel electrophysiology experiments to block sodium leak channels and stretch activated ion channels 58 Gadolinium has recently been used to measure the distance between two points in a protein via electron paramagnetic resonance something that gadolinium is especially amenable to thanks to EPR sensitivity at w band 95 GHz frequencies 59 References Edit Standard Atomic Weights Gadolinium CIAAW 1969 Yttrium and all lanthanides except Ce and Pm have been observed in the oxidation state 0 in bis 1 3 5 tri t butylbenzene complexes see Cloke F Geoffrey N 1993 Zero Oxidation State Compounds of Scandium Yttrium and the Lanthanides Chem Soc Rev 22 17 24 doi 10 1039 CS9932200017 and Arnold Polly L Petrukhina Marina A Bochenkov Vladimir E Shabatina Tatyana I Zagorskii Vyacheslav V Cloke 15 December 2003 Arene complexation of Sm Eu Tm and Yb atoms a variable temperature spectroscopic investigation Journal of Organometallic Chemistry 688 1 2 49 55 doi 10 1016 j jorganchem 2003 08 028 Weast Robert 1984 CRC Handbook of Chemistry and Physics Boca Raton Florida Chemical Rubber Company Publishing pp E110 ISBN 0 8493 0464 4 Donnelly L Nelson R Renal excretion of gadolinium mimicking calculi on non contrast CT Pediatric Radiology 28 417 1998 https doi org 10 1007 s002470050374 a b c d e f Greenwood Norman N Earnshaw Alan 1997 Chemistry of the Elements 2nd ed Butterworth Heinemann ISBN 978 0 08 037941 8 Gadolinium Neutron News 3 3 29 1992 Retrieved 6 June 2009 a b Lide D R ed 2005 CRC Handbook of Chemistry and Physics 86th ed Boca Raton FL CRC Press p 4 122 ISBN 0 8493 0486 5 Coey JM Skumryev V Gallagher K 1999 Rare earth metals Is gadolinium really ferromagnetic Nature 401 6748 35 36 Bibcode 1999Natur 401 35C doi 10 1038 43363 ISSN 0028 0836 S2CID 4383791 Gschneidner Karl Jr Gibson Kerry 7 December 2001 Magnetic refrigerator successfully tested Ames Laboratory Archived from the original on 23 March 2010 Retrieved 17 December 2006 a b Gschneidner K Pecharsky V Tsokol A 2005 Recent Developments in Magnetocaloric Materials PDF Reports on Progress in Physics 68 6 1479 Bibcode 2005RPPh 68 1479G doi 10 1088 0034 4885 68 6 R04 S2CID 56381721 Archived from the original PDF on 9 November 2014 Suenaga Kazu Taniguchi Risa Shimada Takashi Okazaki Toshiya Shinohara Hisanori Iijima Sumio 2003 Evidence for the Intramolecular Motion of Gd Atoms in a Gd2 C92 Nanopeapod Nano Letters 3 10 1395 Bibcode 2003NanoL 3 1395S doi 10 1021 nl034621c Hashimoto A Yorimitsu H Ajima K Suenaga K Isobe H Miyawaki J Yudasaka M Iijima S Nakamura E June 2004 Selective deposition of a gadolinium III cluster in a hole opening of single wall carbon nanohorn Proceedings of the National Academy of Sciences USA 101 23 8527 30 Bibcode 2004PNAS 101 8527H doi 10 1073 pnas 0400596101 PMC 423227 PMID 15163794 Holleman Arnold Frederik Wiberg Egon 2001 Wiberg Nils ed Inorganic Chemistry translated by Eagleson Mary Brewer William San Diego Berlin Academic Press De Gruyter ISBN 0 12 352651 5 Mark Winter 1993 2018 Chemical reactions of Gadolinium The University of Sheffield and WebElements Retrieved 6 June 2009 Cotton 2007 Advanced inorganic chemistry 6th ed Wiley India p 1128 ISBN 978 81 265 1338 3 Danevich F A et al 2001 Quest for double beta decay of 160Gd and Ce isotopes Nucl Phys A 694 1 375 91 arXiv nucl ex 0011020 Bibcode 2001NuPhA 694 375D doi 10 1016 S0375 9474 01 00983 6 S2CID 11874988 Marshall James L Marshall Virginia R 2008 Rediscovery of the Elements Yttrium and Johan Gadolin PDF The Hexagon Spring 8 11 Marshall James L Marshall Marshall Virginia R Marshall 2015 Rediscovery of the elements The Rare Earths The Confusing Years PDF The Hexagon 72 77 Retrieved 30 December 2019 Weeks Mary Elvira 1956 The discovery of the elements 6th ed Easton PA Journal of Chemical Education Weeks Mary Elvira 1932 The discovery of the elements XVI The rare earth elements Journal of Chemical Education 9 10 1751 1773 Bibcode 1932JChEd 9 1751W doi 10 1021 ed009p1751 Deliens M and Piret P 1982 Bijvoetite et lepersonnite carbonates hydrates d uranyle et des terres rares de Shinkolobwe Zaire Canadian Mineralogist 20 231 38 Lepersonnite Gd Lepersonnite Gd mineral information and data Mindat org Retrieved 4 March 2016 National Center for Biotechnology Information Element Summary for AtomicNumber 64 Gadolinium PubChem Retrieved 25 October 2021 a href Template Cite web html title Template Cite web cite web a CS1 maint url status link Liney Gary 2006 MRI in clinical practice Springer pp 13 30 ISBN 978 1 84628 161 7 Raymond KN Pierre VC 2005 Next generation high relaxivity gadolinium MRI agents Bioconjugate Chemistry 16 1 3 8 doi 10 1021 bc049817y PMID 15656568 Wendler Ronda 1 December 2009 Magnets Guide Stem Cells to Damaged Hearts Texas Medical Center Ryzhikov VD Grinev BV Pirogov EN Onyshchenko GM Bondar VG Katrunov KA Kostyukevich SA 2005 Use of gadolinium oxyorthosilicate scintillators in x ray radiometers Optical Engineering 44 016403 Bibcode 2005OptEn 44a6403R doi 10 1117 1 1829713 Sajwan R K Tiwari S Harshit T et al Recent progress in multicolor tuning of rare earth doped gadolinium aluminate phosphors GdAlO3 Opt Quant Electron 49 344 2017 https doi org 10 1007 s11082 017 1158 5 Gadolinium 153 Pacific Northwest National Laboratory Archived from the original on 27 May 2009 Retrieved 6 June 2009 Lixi Inc Retrieved 6 June 2009 Hammond C R The Elements in Lide D R ed 2005 CRC Handbook of Chemistry and Physics 86th ed Boca Raton FL CRC Press ISBN 0 8493 0486 5 Inside the secret underground lair where scientists are searching the galaxies ABC News ABC News Australia 16 June 2019 Retrieved 16 June 2019 Shi Y Babu N Hari Iida K Cardwell D A 1 February 2008 Superconducting properties of Gd Ba Cu O single grains processed from a new Ba rich precursor compound Journal of Physics Conference Series 97 1 012250 Bibcode 2008JPhCS 97a2250S doi 10 1088 1742 6596 97 1 012250 ISSN 1742 6596 Cardwell D A Shi Y H Hari Babu N Pathak S K Dennis A R Iida K 1 March 2010 Top seeded melt growth of Gd Ba Cu O single grain superconductors Superconductor Science and Technology 23 3 034008 Bibcode 2010SuScT 23c4008C doi 10 1088 0953 2048 23 3 034008 ISSN 0953 2048 S2CID 121381965 Zhang Y F Wang J J Zhang X J Pan C Y Zhou W L Xu Y Liu Y S Izumi M 2017 Flux pinning properties of GdBCO bulk through the infiltration and growth process IOP Conference Series Materials Science and Engineering 213 1 012049 Bibcode 2017MS amp E 213a2049Z doi 10 1088 1757 899X 213 1 012049 ISSN 1757 8981 Wang Brian 22 November 2018 European EcoSwing Builds First Full Scale Superconductor Wind Turbine Zhang Yufeng Zhou Difan Ida Tetsuya Miki Motohiro Izumi Mitsuru 1 April 2016 Melt growth bulk superconductors and application to an axial gap type rotating machine Superconductor Science and Technology 29 4 044005 Bibcode 2016SuScT 29d4005Z doi 10 1088 0953 2048 29 4 044005 ISSN 0953 2048 S2CID 124770013 Durrell J H Dennis A R Jaroszynski J Ainslie M D Palmer K G B Shi Y H Campbell A M Hull J Strasik M 1 August 2014 A trapped field of 17 6 T in melt processed bulk Gd Ba Cu O reinforced with shrink fit steel Superconductor Science and Technology 27 8 082001 arXiv 1406 0686 Bibcode 2014SuScT 27h2001D doi 10 1088 0953 2048 27 8 082001 ISSN 0953 2048 S2CID 4890081 Strongest magnetic field trapped in a superconductor Retrieved 15 August 2019 Gadolinium 691771 Sigma Aldrich Bousquet et coll 1988 https www acadpharm org dos public Academie de pharmacie 2014 JM Idee V2 pdf bare URL Ersoy Hale Rybicki Frank J November 2007 Biochemical Safety Profiles of Gadolinium Based Extracellular Contrast Agents and Nephrogenic Systemic Fibrosis Journal of Magnetic Resonance Imaging 26 5 1190 1197 doi 10 1002 jmri 21135 ISSN 1053 1807 PMC 2709982 PMID 17969161 Penfield JG Reilly RF December 2007 What nephrologists need to know about gadolinium Nature Clinical Practice Nephrology 3 12 654 68 doi 10 1038 ncpneph0660 PMID 18033225 S2CID 22435496 Gadolinium Deposition Disease GDD in Patients with Normal Renal Function Gadolinium Toxicity 1 November 2015 Retrieved 3 February 2016 Questions and Answers on Magnetic resonance imaging PDF International Society for Magnetic Resonance in Medicine Archived PDF from the original on 29 November 2007 Retrieved 6 June 2009 Information on Gadolinium Containing Contrast Agents US Food and Drug Administration Archived from the original on 6 September 2008 Gray Theodore 2009 The Elements Black Dog amp Leventhal Publishers ISBN 1 57912 814 9 Thomsen HS Morcos SK Dawson P November 2006 Is there a causal relation between the administration of gadolinium based contrast media and the development of nephrogenic systemic fibrosis NSF Clinical Radiology 61 11 905 06 doi 10 1016 j crad 2006 09 003 PMID 17018301 Semelka RC Ramalho J Vakharia A AlObaidy M Burke LM Jay M Ramalho M December 2016 Gadolinium deposition disease Initial description of a disease that has been around for a while Magnetic Resonance Imaging 34 10 1383 90 doi 10 1016 j mri 2016 07 016 hdl 10400 17 2952 PMID 27530966 S2CID 21239478 a b Schieda N Blaichman JI Costa AF Glikstein R Hurrell C James M Jabehdar Maralani P Shabana W Tang A Tsampalieros A van der Pol CB Hiremath S 2018 Gadolinium Based Contrast Agents in Kidney Disease A Comprehensive Review and Clinical Practice Guideline Issued by the Canadian Association of Radiologists Canadian Journal of Kidney Health and Disease 5 2054358118778573 doi 10 1177 2054358118778573 PMC 6024496 PMID 29977584 ACR Committee on Drugs Contrast Media 2010 ACR Manual on Contrast Media Version 7 ISBN 978 1 55903 050 2 Center for Drug Evaluation and Research FDA warns that gadolinium based contrast agents GBCAs are retained in the body requires new class warnings www fda gov Drug Safety and Availability FDA Drug Safety Communication Retrieved 20 September 2018 Murphy KJ Brunberg JA Cohan RH October 1996 Adverse reactions to gadolinium contrast media a review of 36 cases AJR American Journal of Roentgenology 167 4 847 49 doi 10 2214 ajr 167 4 8819369 PMID 8819369 Gwenzi Willis Mangori Lynda Danha Concilia Chaukura Nhamo Dunjana Nothando Sanganyado Edmond 15 September 2018 Sources behaviour and environmental and human health risks of high technology rare earth elements as emerging contaminants The Science of the Total Environment 636 299 313 Bibcode 2018ScTEn 636 299G doi 10 1016 j scitotenv 2018 04 235 ISSN 1879 1026 PMID 29709849 S2CID 19076605 Rogowska J Olkowska E Ratajczyk W Wolska L June 2018 Gadolinium as a new emerging contaminant of aquatic environments Environmental Toxicology and Chemistry 37 6 1523 34 doi 10 1002 etc 4116 PMID 29473658 Tircso Gyulia Molnar Enrico Csupasz Tibor Garda Zoltan Botar Richard Kalman Ferenc K Kovacs Zoltan Brucher Erno Toth Imre 2021 Chapter 2 Gadolinium III Based Contrast Agents for Magnetic Resonance Imaging A Re Appraisal Metal Ions in Bio Imaging Techniques Springer pp 39 70 doi 10 1515 9783110685701 008 S2CID 233702931 Yeung EW Allen DG August 2004 Stretch activated channels in stretch induced muscle damage role in muscular dystrophy Clinical and Experimental Pharmacology amp Physiology 31 8 551 56 doi 10 1111 j 1440 1681 2004 04027 x hdl 10397 30099 PMID 15298550 S2CID 9550616 Yang Y Yang F Gong Y Bahrenberg T Feintuch A Su X Goldfarb D October 2018 High Sensitivity In Cell EPR Distance Measurements on Proteins using and Optimized Gd III Spin Label The Journal of Physical Chemistry Letters 9 20 6119 23 doi 10 1021 acs jpclett 8b02663 PMID 30277780 S2CID 52909932 External links Edit Wikimedia Commons has media related to Gadolinium Look up gadolinium in Wiktionary the free dictionary Nephrogenic Systemic Fibrosis Complication of Gadolinium MR Contrast series of images at MedPix website It s Elemental Gadolinium Refrigerator uses gadolinium metal that heats up when exposed to magnetic field FDA advisory on gadolinium based contrast Abdominal MR imaging important considerations for evaluation of gadolinium enhancement Rafael O P de Campos Vasco Heredia Ersan Altun Richard C Semelka Department of Radiology University of North Carolina Hospitals Chapel Hill Inside Japan s Super Kamiokande 360 degree tour including details on adding Gadolinium to the pure water to aid in studying neutrinos Retrieved from https en wikipedia org w index php title Gadolinium amp oldid 1129716850, wikipedia, wiki, book, books, library,

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