Rubidium,Strontium,Yttrium,Zirconium

Rubidium is a chemical element with the symbol Rb and atomic number 37. Rubidium is a soft, silvery-white metallic element of the alkali metal group. Its atomic mass is 85.4678. Elemental rubidium is highly reactive, with properties similar to those of other elements in group 1, such as very rapid oxidation in air.Sony VAIO VPCY21S1E/SI Battery

Rubidium has only one stable isotope, 85Rb. The isotope 87Rb, which composes almost 28% of naturally occurring rubidium, is radioactive and has ahalf-life of 49 billion years—more than three times longer than the estimated age of the universe.Sony VAIO VPCZ110 Battery

German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed method of flame spectroscopy. Its compounds have chemical and electronic applications. Rubidium metal is easily vaporized and has a convenient spectral absorption range, making it a frequent target for laser manipulation of atoms.Sony VAIO VPCZ110GB/BI Battery

Rubidium is not known to be necessary for any living organisms. However, like caesium, rubidium ions are handled by living organisms in a manner similar to potassium ions: they are actively taken up by plants and living animal cells.Sony VAIO VPCZ112GD/S Battery

Characteristics

Rubidium is a very soft, ductile, silvery-white metal. It is the second most electropositive of the non-radioactive alkali metals and melts at a temperature of 39.3 °C (102.7 °F).Sony VAIO VPCZ112GX/S Battery

Similar to other alkali metals, this metal reacts violently with water, forms amalgams with mercury and alloys with gold, iron, caesium, sodium, and potassium, but not lithium (despite the fact that rubidium and lithium are in the same group).Sony VAIO VPCZ114GX/S Battery

As with potassium (which is slightly less reactive) and caesium (which is slightly more reactive), this reaction is usually vigorous enough to ignite the hydrogen gas it liberates. Rubidium has also been reported to ignite spontaneously in air.[2] Rubidium has a very low ionization energy of only 406 kJ/mol.Sony VAIO VPCZ115 Battery

Rubidium and potassium show a very similar violet color in the flame test, which makes spectroscopy methods necessary to distinguish the two elements.

Compounds

Rubidium chloride (RbCl) is probably the most used rubidium compound;Sony VAIO VPCZ115FC/B Battery

it is used in biochemistry to induce cells to take upDNA, and as a biomarker since it is readily taken up to replace potassium, and occurs in only small quantities in living organisms. Other common rubidium compounds are the corrosive rubidium hydroxide (RbOH), the starting material for most rubidium-based chemical processes;Sony VAIO VPCZ115FC/S Battery

rubidium carbonate (RbCO3), which is used in some optical glasses, and rubidium copper sulfate, Rb2SO4•CuSO4•6H2O. Rubidium silver iodide (RbAg4I5) has the highest room temperature conductivity of any known ionic crystal, a property that is being exploited in thin film batteries and other applications.Sony VAIO VPCZ116 Battery

Rubidium has a number of oxides, including rubidium monoxide (Rb2O), Rb6O and Rb9O2, which form if rubidium metal is exposed to air; rubidium in excess oxygen gives the superoxide RbO2. Rubidium forms salts with halides, making rubidium fluoride, rubidium chloride, rubidium bromide and rubidium iodide.Sony VAIO VPCZ116GX/S Battery

Naturally occurring rubidium is composed of two isotopes: the stable 85Rb (72.2%) and the radioactive 87Rb (27.8%).[7] Natural rubidium is radioactive with specific activity of about 670 Bq/g, enough to significantly expose a photographic film in 110 daysSony VAIO VPCZ117 Battery

Aside from 85Rb and 87Rb, another 24 isotopes are known with half times of under 3 months. Most of them are highly radioactive and have little uses.

Rubidium-87 has a half-life of 48.8×109 years, which is more than three times the age of the universe of 13.75 ± 0.11 ×109years,[10]making it a Primordial nuclide.Sony VAIO VPCZ117FC/B Battery

It readily substitutes for potassium in minerals, and is therefore fairly widespread. Rb has been used extensively in dating rocks; 87Rb decays to stable 87Sr by emission of a negative beta particle. During fractional crystallization, Sr tends to become concentrated in plagioclase, leaving Rb in the liquid phase.Sony VAIO VPCZ118 Battery

Hence, the Rb/Sr ratio in residual magma may increase over time, resulting in rocks with elevated Rb/Sr ratios due to progressingdifferentiation. The highest ratios (10 or more) occur in pegmatites. If the initial amount of Sr is known or can be extrapolated then the age can be determined by measurement of the Rb and Sr concentrations and of the 87Sr/86Sr ratio.Sony VAIO VPCZ118GC/B Battery

The dates indicate the true age of the minerals only if the rocks have not been subsequently altered (see rubidium-strontium dating).

One of the non-natural isotopes rubidium-82 is produced by electron capture decay of Strontium-82 with a half-life of 25.36 days.Sony VAIO VPCZ118GX/S Battery

The subsequent decay of rubidium-82 with a half-life of 76 seconds to stable krypton-82 happens by positron emission.

Occurrence

Rubidium is the twenty-third most abundant element in the Earth's crust, roughly as abundant as zinc and rather more common than copper.Sony VAIO VPCZ119 Battery

It occurs naturally in the minerals leucite, pollucite, carnallite and zinnwaldite, which contain up to 1% of its oxide. Lepidolite contains between 0.3% and 3.5% rubidium and this is the commercial source of the element.[14] Somepotassium minerals and potassium chlorides also contain the element in commercially significant amounts.Sony VAIO VPCZ119FJ/S Battery

Sea water contains an average of 125 µg/L of rubidium compared to the much higher value for potassium of 408 mg/L and the much lower value of 0.3 µg/L for caesium.

Because of its large ionic radius, rubidium is one of the "incompatible elements."Sony VAIO VPCZ119GC/X Battery

During magma crystallization, rubidium is concentrated together with its heavier analogue caesium in the liquid phase and crystallizes last. Therefore the largest deposits of rubidium and caesium are zone pegmatite ore bodies formed by this enrichment process.Sony VAIO VPCZ119L Battery

Because rubidium substitutes for potassium in the crystallization of magma, the enrichment is far less effective than in the case of caesium. Zone pegmatite ore bodies containing mineable quantities of caesium as pollucite or the lithium minerals lepidolite are also a source for rubidium as a by-product.Sony VAIO VPCZ119R/B Battery

Two notable sources of rubidium are the rich deposits of pollucite at Bernic Lake, Manitoba. Both of these are also sources of caesium. Rubicline ((Rb,K)AlSi3O8) found as impurities in pollucite on the Italian island of Elba with a rubidium content of 17.5%Sony VAIO VPCZ119R/S Battery

Production

Although rubidium is more abundant in Earth's crust than caesium the limited applications and the lack of a mineral rich in rubidium limits the production of rubidium compounds to 2 to 4 tonnes per year. There are several methods to separate potassium, rubidium and caesium.Sony VAIO VPCZ11AFJ Battery

The fractional crystallization of a rubidium and caesium alum (Cs,Rb)Al(SO4)2·12H2O yields after 30 subsequent steps pure rubidium alum. Reports of two other methods are given in the literature the chlorostannate process and the ferrocyanide process.Sony VAIO VPCZ11AGJ Battery

For several years in the 1950s and 1960s a by-product of the potassium production called Alkarb was a main source for rubidium. Alkarb contained 21% rubidium while the rest was potassium and a small fraction of caesium. Today the largest producers of caesium, for example the Tanco Mine, Manitoba, Canada, produce rubidium as by-product from pollucite.Sony VAIO VPCZ11AVJ Battery

Rubidium was discovered in 1861 by Robert Bunsen and Gustav Kirchhoff, in Heidelberg, Germany, in the mineral lepidolitethrough the use of a spectroscope. Because of the bright red lines in its emission spectrum, they chose a name derived from the Latin word rubidus, meaning "dark red".Sony VAIO VPCZ11CGX/X Battery

Rubidium is present as a minor component in lepidolite. Kirchhoff and Bunsen processed 150 kg of a lepidolite containing only 0.24% rubidium oxide (Rb2O). Potassium, rubidium form insoluble salts with chloroplatinic acid, but these salts show a slight difference in solubility in hot water.Sony VAIO VPCZ11DGX/SJ Battery

Therefore, the less-soluble rubidium hexachloroplatinate (Rb2PtCl6) could be obtained byfractional crystallization. After reduction of the hexachloroplatinate with hydrogen, rubidium could be separated by the difference in solubility of their carbonates in alcohol. This process yielded 0.51 grams of rubidium chloride for further studies.Sony VAIO VPCZ11FHX/XQ Battery

The first large scale isolation of caesium and rubidium compounds, performed from 44,000 liters of mineral water by Bunsen and Kirchhoff, yielded, besides 7.3 grams of caesium chloride, also 9.2 grams of rubidium chloride.Rubidium was the second element, shortly after caesium, to be discoveredspectroscopically, only one year after the invention of the spectroscope by Bunsen and Kirchhoff.Sony VAIO VPCZ11V9R/B Battery

The two scientists used the rubidium chloride thus obtained to estimate the atomic weight of the new element as 85.36 (the currently accepted value is 85.47). They tried to generate elemental rubidium by electrolysis of molten rubidium chloride, but instead of a metal,Sony VAIO VPCZ11X9E/B Battery

they obtained a blue homogenous substance which "neither under the naked eye nor under the microscope showed the slightest trace of metallic substance." They assigned it as a subchloride (Rb2Cl); however, the product was probably a colloidal mixture of the metal and rubidium chloride.Sony VAIO VPCZ11Z9E/B Battery

In a second experiment to produce metallic rubidium Bunsen was able to reduce rubidium by heating charred rubidium tartrate. Although the distilled rubidium was pyrophoric it was possible to determine the density and the melting point of rubidium.Sony VAIO VPCZ125GX/S Battery

The quality of the research done in the 1860s can be appraised by the fact that the determined density differs less than 0.1 g/cm3and the melting point by less than 1 °C from the presently accepted values.

The slight radioactivity of rubidium was discovered in 1908 but before the theory of isotopes was established in the 1910s and the low activity due to the long half-life of above 1010 years made interpretation complicated.Sony VAIO VPCZ127FC Battery

The now proven decay of 87Rb to stable 87Sr through beta decay was still under discussion in the late 1940s.

Rubidium had minimal industrial value before the 1920s. Since then, the most important use of rubidium has been in research and development, primarily in chemical and electronic applications.Sony VAIO VPCZ128GC Battery

In 1995, rubidium-87 was used to produce a Bose-Einstein condensate, for which the discoverers won the 2001 Nobel Prize in Physics.

Applications

Rubidium compounds are sometimes used in fireworks to give them a purple color.Sony VAIO VPCZ12M9E/B Battery

Rubidium has also been considered for use in athermoelectric generator using the magnetohydrodynamic principle, where rubidium ions are formed by heat at high temperature and passed through a magnetic field. These conduct electricity and act like an armature of a generator thereby generating anelectric current.Sony VAIO VPCZ13M9E/B Battery

Rubidium, particularly vaporized 87Rb, is one of the most commonly used atomic species employed for laser cooling and Bose-Einstein condensation. Its desirable features for this application include the ready availability of inexpensivediode laser light at the relevant wavelength, and the moderate temperatures required to obtain substantial vapor pressures.Sony VAIO VPCZ13V9E/X Battery

Rubidium has been used for polarizing 3He, producing volumes of magnetized 3He gas, with the nuclear spins aligned toward a particular direction in space, rather than randomly. Rubidium vapor is optically pumped by a laser and the polarized Rb polarizes3He through the hyperfine interaction.Sony VAIO VPCZ13Z9E/X Battery

Spin-polarized 3He cells are becoming popular for neutron polarization measurements and for producing polarized neutron beams for other purposes.

Rubidium is the main component of secondary frequency references (rubidium oscillators) to maintain frequency accuracy in cell site transmitters and other electronic transmitting, networking and test equipment.Sony VAIO VPCZZZHJ Battery

This rubidium standard are often used withGPS to produce a "primary frequency standard" that has greater accuracy and is less expensive than caesium standards. Rubidium standards are mass-produced for the telecommunication industry.Sony VAIO VPZ117 Battery

Other potential or current uses of rubidium include a working fluid in vapor turbines, a getter in vacuum tubes and a photocellcomponent. The resonant element in atomic clocks utilizes the hyperfine structure of rubidium's energy levels.Sony VAIO VPZ118 Battery

Rubidium is also used as an ingredient in special types of glass, in the production of superoxide by burning in oxygen, in the study of potassium ion channels in biology and as the vapor to make atomic magnetometers. In particular, 87Rb is currently being used, with other alkali metals, in the development of spin-exchange relaxation-free (SERF) magnetometers.Sony VAIO VPZ119 Battery

Rubidium-82 is used for positron emission tomography. Rubidium is very similar to potassium and therefore tissue with high potassium content will also accumulate the radioactive rubidium. One of the main uses is in myocardial perfusion imaging. The very short half-life of 76 seconds makes it necessary to produce the rubidium-82 from decay of strontium-82 close to the patient.Sony VPCM11M1E/B Battery

As a result of changes in the blood brain barrier in brain tumors, rubidium collects more in brain tumors than normal brain tissue, allowing to use the radioisotope rubidium-82 in nuclear medicine to locate and image brain tumors.

Rubidium was tested for the influence on manic depression and depression.Sony VPCM11M1E/W Battery

Dialysis patients suffering from depression show a depletion in rubidium and therefore a supplementation may help during depression. In some tests the rubidium was administered as rubidium chloride with up to 720 mg.

Precautions and biological effects

Rubidium reacts violently with water and can cause fires.Sony VPCM12M1E/L Battery

To ensure safety and purity, this metal is kept under a dry mineral oil and is usually sealed in glass ampoules in an inert atmosphere. Rubidium forms peroxides on exposure even to small amount of air diffusing into oil, and is thus subject to similar peroxide precautions as storage of metallic potassium.Sony VPCM12M1E/P Battery

Rubidium, like sodium and potassium, almost always has +1 oxidation state when dissolved in water, and this includes all biological systems. The human body tends to treat Rb+ ions as if they were potassium ions, and therefore concentrates rubidium in the body's intracellular fluid (i.e., inside cells).Sony VPCM12M1E/W Battery

The ions are not particularly toxic, a 70 kg person contains on average 0.36 g of rubidium and an increase in this value by 50 to 100 times did not show negative effects in test persons. The biological half-life in humans was measured as 31–46 days. Although a partial substitution of potassium by rubidium is possible, rats with more than 50% of potassium substituted in the muscle tissue died.Sony VPCM13M1E/L Battery

Strontium is a chemical element with the symbol Sr and the atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when exposed to air. It occurs naturally in the minerals celestine and strontianite.Sony VPCM13M1E/P Battery

While natural strontium is stable, the synthetic 90Sr isotope is present in radioactive fallout and has a half-life of 28.90 years. Both strontium and strontianite are named after Strontian, a village in Scotland near which the mineral was first discovered.Sony VPCM13M1E/W Battery

Strontium is a grey, silvery metal that is softer than calcium and even more reactive inwater, with which it reacts on contact to produce strontium hydroxide and hydrogen gas. It burns in air to produce both strontium oxide and strontium nitride, but since it does not react with nitrogen below 380 °C, at room temperature it will only form the oxide spontaneously.Sony VAIO VGN-Z11MN/B Battery

Because of its extreme reactivity with oxygen and water, this element occurs naturally only in compounds with other elements, such as in the minerals strontianite and celestite. It is kept under a liquid hydrocarbon such as mineral oil or kerosene to preventoxidation;Sony VAIO VGN-Z11VN/X Battery

freshly exposed strontium metal rapidly turns a yellowish color with the formation of the oxide. Finely powdered strontium metal is pyrophoric meaning it will ignite spontaneously in air at room temperature. Volatile strontium salts impart a brightred color to flames, and these salts are used in pyrotechnics and in the production offlares.Sony VAIO VGN-Z11WN/B Battery

Natural strontium is a mixture of four stable isotopes.

Strontium is named after the Scottish village of Strontian (Gaelic Sron an t-Sithein), having been discovered in the ores taken from the lead mines. In 1790, Adair Crawford, a physician engaged in the preparation of barium, recognised that the Strontian ores exhibited different properties to those normally seen with other "heavy spars" sources.Sony VAIO VGN-Z11XN/B Battery

This allowed him to conclude "... it is probable indeed, that the scotch mineral is a new species of earth which has not hitherto been sufficiently examined". The new mineral was named strontites in 1793 by Thomas Charles Hope, a professor of chemistry at the University of Glasgow.Sony VAIO VGN-Z15 Battery

He confirmed the earlier work of Crawford and recounted: " ... Considering it a peculiar earth I thought it necessary to give it an name. I have called it Strontites, from the place it was found; a mode of derivation in my opinion, fully as proper as any quality it may possess, which is the present fashion".Sony VAIO VGN-Z15N Battery

The element was eventually isolated by SirHumphry Davy in 1808 by the electrolysis of a mixture containing strontium chloride and mercuric oxide, and announced by him in a lecture to the Royal Society on 30 June 1808.[7] In keeping with the naming of the other alkaline earths, he changed the name to strontium.Sony VAIO VGN-Z17 Battery

The first large scale application of strontium was in the production of sugar from sugar beet. Although a crystallisation process using strontium hydroxide was patented by Augustin-Pierre Dubrunfaut in 1849 the large scale introduction came with the improvement of the process in the early 1870s.Sony VAIO VGN-Z17N Battery

The German sugar industry used the process well into the 19th century. Prior to World War I the beet sugar industry used 100,000 to 150,000 tons of strontium hydroxide for this process per year. The strontium hydroxide was recycled in the process, but the demand to substitute losses during production was high enough to create a significant demand initiating mining of strontianite in the Münsterland.Sony VAIO VGN-Z19 Battery

The mining of strontianite in Germany ended when mining of the celestite deposits in Gloucestershire started. These mines supplied most of the world strontium supply from 1884 to 1941.

According to the British Geological Survey, China was the top producer of strontium in 2007, with over two-thirds world share, followed by Spain, Mexico, Turkey, Argentina and Iran.Sony VAIO VGN-Z19N Battery

Strontium commonly occurs in nature, the 15th most abundant element on earth, averaging 0.034% of all igneous rock and is found chiefly as the form of the sulfate mineralcelestite (SrSO4) and the carbonate strontianite (SrCO3). Of the two, celestite occurs much more frequently in sedimentary deposits of sufficient size to make development of mining facilities attractive.Sony VAIO VGN-Z21MN/B Battery

Strontianite would be the more useful of the two common minerals because strontium is used most often in the carbonate form, but few deposits have been discovered that are suitable for development. The metal can be prepared by electrolysis of melted strontium chloride mixed with potassium chloride:Sony VAIO VGN-Z21VN/X Battery

Sr2+ + 2 e?? Sr2 Cl? ? Cl2 (g) + 2 e?

Alternatively it is made by reducing strontium oxide with aluminium in a vacuum at a temperature at which strontium distillsoff. Three allotropes of the metal exist, with transition points at 235 and 540 °C.Sony VAIO VGN-Z21WN/B Battery

Strontium has four stable, naturally occurring isotopes: 84Sr (0.56%), 86Sr (9.86%), 87Sr (7.0%) and 88Sr (82.58%). Only 87Sr is radiogenic; it is produced by decay from the radioactive alkali metal 87Rb, which has a half-life of 4.88 × 1010 years.Sony VAIO VGN-Z21XN Battery

Thus, there are two sources of 87Sr in any material: that formed in stars along with 84Sr, 86Sr and 88Sr, as well as that formed by radioactive decay of 87Rb. The ratio 87Sr/86Sr is the parameter typically reported in geologic investigations; ratios in minerals and rocks have values ranging from about 0.7 to greater than 4.0.Sony VAIO VGN-Z21ZN/X Battery

Because strontium has an atomic radiussimilar to that of calcium, it readily substitutes for Ca in minerals.

Sixteen unstable isotopes are known to exist. Of greatest importance are 90Sr with a half-life of 28.78 years and 89Sr with ahalf-life of 50.5 days.Sony VAIO VGN-Z25 Battery

90Sr is a by-product of nuclear fission found in nuclear fallout and presents a health problem since it substitutes for calcium in bone, preventing expulsion from the body. This isotope is one of the best long-lived high-energy beta emitters known, and is used in SNAP (Systems for Nuclear Auxiliary Power) devices.Sony VAIO VGN-Z25/B Battery

These devices hold promise for use in spacecraft, remote weather stations, navigational buoys, etc., where a lightweight, long-lived, nuclear-electric power source is required. The 1986 Chernobyl nuclear accident contaminated a vast area with 90Sr. 90Sr confined inside a concave silver plaque is also used for the medical treatment of a resected pterygium.Sony VAIO VGN-Z25TN/B Battery

89Sr is a short-lived artificial radioisotope that is used in the treatment of bone cancer. In circumstances where cancer patients have widespread and painful bony metastases (secondaries), the administration of 89Sr results in the delivery of radioactive emissions (beta particles in this case) directly to the area of bony problem (where calcium turnover is greatest).Sony VAIO VGN-Z26TN/B Battery

The 89Sr is manufactured as the chloride salt (which is soluble), and when dissolved in normal saline can be injected intravenously. Typically, cancer patients will be treated with a dose of 150 MBq. Patients must take precautions following this because their urine becomes contaminated with radioactivity, so they must sit to urinate and double-flush the toilet.Sony VAIO VGN-Z27 Battery

The beta particles travel about 3.5 mm in bone (energy 0.583 MeV) and 6.5 mm in tissue, so there is no requirement to isolate patients having been treated, except to say they should not have any one (especially young children) sitting in their laps for 10–40 days .Sony VAIO VGN-Z27/B Battery

The variation in time results from the variable clearing time for 89Sr, which depends on renal function and the number of bony metastases. With a lot of bony metastases, the entire 89Sr dose can be taken up into bone and so the radioactivity is retained to decay over a 50.5-day half-life.Sony VAIO VGN-Z27TN/X Battery

It takes about 10 half-lives or about 500 days for 99.9% of the radioactive strontium to decay. However, where there are few bony metastases, the large proportion of 89Sr not taken up by the bone will be filtered by the kidney, so that the effective half-life (a combination of the physical and biological half-life) will be much shorter.Sony VAIO VGN-Z29N Battery

Applications

As a pure metal strontium is used in strontium 90%-aluminium 10% alloys of an eutectic composition for the modification of aluminium-silicon casting alloys. Strontium is 2% by weight of AJ62 alloy, a durable, creep-resistant magnesium alloy used in car and motorcycle engines by BMW.Sony VAIO VGN-Z29N/X Battery

Strontium is used in scientific studies of neurotransmitter release in neurons. Like calcium, strontium facilitates synaptic vesicle fusion with the synaptic membrane. But, unlike calcium, strontium causes asynchronous vesicle fusion. Therefore, replacing calcium in the culture medium with strontium allows scientists to measure the effects of a single-vesicle fusion event,Sony VAIO VGN-Z31MN/B Battery

e.g., the size of the postsynaptic response elicited by the neurotransmitter content of a single vesicle.

In general, strontium salts often strontium carbonate are used in the manufacture of fireworks, as they impart a deep red colour to the firework.Sony VAIO VGN-Z31VN/X Battery

Compounds

The primary use for strontium compounds is in glass for colour television cathode ray tubes to prevent X-ray emission. All parts of the CRT tube have to absorb X-rays. In the neck and the funnel of the tube, lead glass is used for this purpose, but this type of glass shows a browning effect due to the interaction of the X-rays with the glass.Sony VAIO VGN-Z31WN/B Battery

Therefore, the front panel has to use a different glass mixture, in which strontium and barium are the X-ray-absorbing materials. The average values for the glass mixture determined for a recycling study in 2005 is 8.5% strontium oxide and 10% barium oxide.

Other applications are as follows:Sony VAIO VGN-Z31ZN/X Battery

• Ferrite magnets and refining zinc.
• Strontium titanate has an extremely high refractive index and an optical dispersion greater than that of diamond, making it useful in a variety of optics applications. This quality has also led to its being cut into gemstones, in particular as adiamond simulant. However, it is very soft and easily scratches so it is rarely used.Sony VAIO VGN-Z35 Battery

• Strontium carbonate, strontium nitrate, and strontium sulfate are commonly used in fireworks for red color, and sometimes for other colors too.
• Strontium aluminate is used as a bright phosphor with long persistence of phosphorescence.Sony VAIO VGN-Z35/B Battery

• Strontium chloride is sometimes used in toothpastes for sensitive teeth. One popular brand includes 10% total strontium chloride hexahydrate by weight.
• Strontium oxide is sometimes used to improve the quality of some pottery glazes.Sony VAIO VGN-Z35TN/B Battery

• Strontium ranelate is used in the treatment of osteoporosis. It is a prescription drug in the EU, but not in the USA.
• Strontium barium niobate can be used in outdoors holographic 3D displays as a "screen".
• Strontium phosphide is an inorganic compound with the formula Sr3P2 and is used as a laboratory reagent and in the manufacture of chemically reactive devices.Sony VAIO VGN-Z36GD Battery

Radioactive strontium isotopes

89Sr is the active ingredient in Metastron (the generic version of Metastron, Generic Strontium Chloride Sr-89 Injection, its manufactured by Bio-Nucleonics Inc. ), a radiopharmaceutical used for bone pain secondary to metastatic bone cancer.Sony VAIO VGN-Z36GD/B Battery

The strontium acts like calcium and is preferentially incorporated into bone at sites of increased osteogenesis. This localization focuses the radiation exposure on the cancerous lesion.

(RTGs). 90Sr produces about 0.93 watts of heat per gram (it is lower for the form of 90Sr used in RTGs, which is strontium fluoride).Sony VAIO VGN-Z36GD/J Battery

However, 90Sr has a lifetime approximately 3 times shorter and has a lower density than 238Pu, another RTG fuel. The main advantage of 90Sr is that it is cheaper than 238Pu and is found in nuclear waste. Soviet Union deployed nearly 1000 of these RTGs on the northern coast as power source for lighthouses and meteorology stations.Sony VAIO VGN-Z36TD/B Battery

90Sr is also used in cancer therapy. Its beta emission and long half-life is ideal for superficial radiotherapy.

Because strontium is so similar to calcium, it is incorporated in the bone. All four stable isotopes are incorporated, in roughly similar proportions, as they are found in nature (please see below).Sony VAIO VGN-Z36TD/J Battery

However, the actual distribution of the isotopes tends to vary greatly from one geographical location to another. Thus, analyzing the bone of an individual can help determine the region it came from. This approach helps to identify the ancient migration patterns as well as the origin of commingled human remains in battlefield burial sites. Strontium, thus, helps forensic scientists too.Sony VAIO VGN-Z37D Battery

87Sr/86Sr ratios are commonly used to determine the likely provenance areas of sediment in natural systems, especially in marine and fluvial environments. Dasch (1969) showed that surface sediments of Atlantic displayed 87Sr/86Sr ratios that could be regarded as bulk averages of the 87Sr/86Sr ratios of geological terranes from adjacent landmasses.Sony VAIO VGN-Z37D/B Battery

A good example of a fluvial-marine system to which Sr isotope provenance studies have been successfully employed is the River Nile-Mediterranean system, Due to the differing ages of the rocks that constitute the majority of the Blue and White Nile, catchment areas of the changing provenance of sediment reaching the River Nile delta and East Mediterranean Sea can be discerned through Sr isotopic studies. Such changes are climatically controlled in the Late Quaternary.Sony VAIO VGN-Z37GD Battery

More recently, 87Sr/86Sr ratios have also been used to determine the source of ancient archaeological materials such as timbers and corn in Chaco Canyon, New Mexico 87Sr/86Sr ratios in teeth may also be used to track animal migrations [34][35] or in criminal forensics.Sony VAIO VGN-Z37GD/X Battery

Effect on the human body

The human body absorbs strontium as if it were calcium. Due to the chemical similarity of the elements, the stable forms of strontium might not pose a significant health threat — in fact, the levels found naturally may actually be beneficial (see below) -Sony VAIO VGN-Z39D Battery

but the radioactive 90Sr can lead to various bone disorders anddiseases, including bone cancer. The strontium unit is used in measuring radioactivity from absorbed 90Sr.

A recent in-vitro study conducted the NY College of Dental Sciences using strontium on osteoblasts showed marked improvement on bone-building osteoblasts.Sony VAIO VGN-Z39D/X Battery

The drug strontium ranelate, made by combining strontium with ranelic acid, was found to aid bone growth, increase bone density, and lessen vertebral, peripheral, and hip fractures. Women receiving the drug showed a 12.7% increase in bone density. Women receiving a placebo had a 1.6% decrease.Sony VAIO VGN-Z41MD/B Battery

Half the increase in bone density (measured by X-ray densitometry) is attributed to the higher atomic weight of Sr compared with calcium, whereas the other half a true increase in bone mass. Strontium ranelate is registered as a prescription drug in Europe and many countries worldwide.Sony VAIO VGN-Z41WD/B Battery

It must be prescribed by a doctor, must be delivered by a pharmacist, and requires strict medical supervision.

There is a long history of medical research regarding strontium's benefits, beginning in the 1950s. Studies indicate a lack of undesirable side-effects.Sony VAIO VGN-Z45GD/B Battery

Several other salts of strontium such as strontium citrate and strontium carbonate are available in the United States under the Dietary Supplements Health and Education Act of 1994, providing close to the recommended strontium content, about 680 milligrams per day, of strontium ranelate.Sony VAIO VGN-Z45TD/B Battery

Their long-term safety and efficacy have not been evaluated on humans in large-scale medical trials.

Yttrium is a chemical element with symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and it has often been classified as a "rare earth element".Sony VAIO VGN-Z46GD/B Battery

Yttrium is almost always found combined with the lanthanides in rare earth minerals and is never found in nature as a free element. Its only stable isotope, 89Y, is also its only naturally occurring isotope.

In 1787, Carl Axel Arrhenius found a new mineral near Ytterby in Sweden and named it ytterbite, after the village.Sony VAIO VGN-Z46GD/U Battery

Johan Gadolin discovered yttrium's oxide in Arrhenius' sample in 1789,[3] and Anders Gustaf Ekeberg named the new oxide yttria. Elemental yttrium was first isolated in 1828 by Friedrich Wöhler.[4]

The most important use of yttrium is in making phosphors, such as the red ones used in television set cathode ray tube (CRT) displays and in LEDs.Sony VAIO VGN-Z46MD/B Battery

Other uses include the production of electrodes, electrolytes, electronic filters, lasers andsuperconductors; various medical applications; and as traces in various materials to enhance their properties. Yttrium has no known biological role, and exposure to yttrium compounds can cause lung disease in humans.Sony VAIO VGN-Z46SD/B Battery

Properties

Yttrium is a soft, silver-metallic, lustrous and highly crystalline transition metal in group 3. As expected by periodic trends, it is less electronegative than its predecessor in the group, scandium, more electronegative than its successor in the group, lanthanum, and less electronegative than the next member of period 5, zirconium.Sony VAIO VGN-Z46TD/B Battery

Yttrium is the first d-block element in the fifth period.

The pure element is relatively stable in air in bulk form, due to passivation resulting from the formation of a protective oxide (Y2O3) film on its surface. This film can reach a thickness of 10 µm when yttrium is heated to 750 °C in water vapor.Sony VAIO VGN-Z46TD/R Battery

When finely divided, however, yttrium is very unstable in air; shavings or turnings of the metal can ignite in air at temperatures exceeding 400 °C.[4] Yttrium nitride (YN) is formed when the metal is heated to 1000 °C in nitrogen.Sony VAIO VGN-Z47GD/X Battery

Similarity to the lanthanides

The similarities of yttrium to the lanthanides are so strong that the element has historically been grouped with them as arare earth element,[2] and is always found in nature together with them in rare earth minerals.Sony VAIO VGN-Z48GD/X Battery

Chemically, yttrium resembles these elements more closely than its neighbor in the periodic table, scandium,[11] and if its physical properties were plotted against atomic number then it would have an apparent number of 64.5 to 67.5, placing it between the lanthanides gadolinium and erbium.Sony VAIO VGN-Z48TD/X Battery

It often also falls in the same range for reaction order,[9] resembling terbium and dysprosium in its chemical reactivity.[5]Yttrium is so close in size to the so-called 'Yttrium group' of heavy lanthanide ions that in solution, it behaves as if it were one of them.Sony VAIO VGN-Z51WG/B Battery

Even though the lanthanides are one row farther down the periodic table than yttrium, the similarity in atomic radius may be attributed to the lanthanide contraction.[14]

One of the few notable differences between the chemistry of yttrium and that of the lanthanides is that yttrium is almost exclusively trivalent, whereas about half of the lanthanides can have valences other than three.Sony VAIO VGN-Z51XG/B Battery

Compounds and reactions

As a trivalent transition metal, yttrium forms various inorganic compounds, generally in the oxidation state of +3, by giving up all three of its valence electrons.[15] A good example is yttrium(III) oxide (Y2O3), also known as yttria, a six-coordinate white solid.Sony VAIO VGN-Z530N/B Battery

Yttrium forms a water-insoluble fluoride, hydroxide, and oxalate, but its bromide, chloride, iodide, nitrate and sulfate are all soluble in water.[9] The Y3+ ion is colorless in solution because of the absence of electrons in the d and f electron shells.[9]

Water readily reacts with yttrium and its compounds to form Y2O3. Concentrated nitric and hydrofluoric acids do not rapidly attack yttrium, but other strong acids do.Sony VAIO VGN-Z540EBB Battery

With halogens, yttrium forms trihalides such as yttrium(III) fluoride (YF3), yttrium(III) chloride (YCl3), and yttrium(III) bromide (YBr3) at temperatures above roughly 200 °C.[6] Similarly, carbon, phosphorus, selenium, silicon and sulfur all formbinary compounds with yttrium at elevated temperatures.Sony VAIO VGN-Z540NLB Battery

Organoyttrium chemistry is the study of compounds containing carbon–yttrium bonds. A few of these are known to have yttrium in the oxidation state 0. (The +2 state has been observed in chloride melts, and +1 in oxide clusters in the gas phase. ) Some trimerization reactions were observed by using organoyttrium compounds as catalysts.Sony VAIO VGN-Z540NMB Battery

These compounds useYCl3 as a starting material, which in turn is obtained from Y2O3 and concentrated hydrochloric acid and ammonium chloride.

Hapticity is how a group of contiguous atoms of a ligand are coordinated to a central atom; it is indicated by the Greek character eta, ?.Sony VAIO VGN-Z550N/B Battery

Yttrium complexes were the first examples of complexes where carboranyl ligands were bound to a d0-metal center through a ?7-hapticity. Vaporization of the graphite intercalation compounds graphite–Y or graphite–Y2O3 leads to the formation of endohedral fullerenes such as Y@C82.Sony VAIO VGN-Z55F Battery

Electron spin resonance studies indicated the formation of Y3+and (C82)3? ion pairs.[5] The carbides Y3C, Y2C, and YC2 can each hydrolyze to form hydrocarbons.

Nucleosynthesis and isotopes

Yttrium in the Solar System was created through stellar nucleosynthesis, mostly by the s-process (?72%), but also by the r-process (?28%).Sony VAIO VGN-Z55TG/B Battery

The r-process consists of rapid neutron capture of lighter elements during supernova explosions. The s-process is a slow neutron capture of lighter elements inside pulsating red giant stars.[24]

Yttrium isotopes are among the most common products of the nuclear fission of uranium occurring in nuclear explosions and nuclear reactors.Sony VAIO VGN-Z56GG/B Battery

In terms of nuclear waste management, the most important isotopes of yttrium are 91Y and 90Y, with half-lives of 58.51 days and 64 hours, respectively.[25] Though 90Y has the short half-life, it exists in secular equilibrium with its long-lived parent isotope, strontium-90 (90Sr) with a half-life of 29 years.Sony VAIO VGN-Z56GG/E Battery

All group three elements have an odd atomic number, and therefore they have few stable isotopes.[7] Scandium has one stable isotope, and yttrium itself has only one stable isotope, 89Y, which is also its only naturally occurring one. However, thelanthanide rare earths contain elements of even atomic number and many stable isotopes.Sony VAIO VGN-Z56GGX Battery

Yttrium-89 is thought to be more abundant than it otherwise would be, due in part to the s-process which allows enough time for isotopes created by other processes to decay by electron emission (neutron ? proton). Such a slow process tends to favor isotopes with atomic mass numbersSony VAIO VGN-Z56TG/B Battery

(A = protons + neutrons) around 90, 138 and 208, which have unusually stable atomic nuclei with 50, 82, and 126 neutrons, respectively. 89Y has a mass number close to 90 and has 50 neutrons in its nucleus.

At least 32 synthetic isotopes of yttrium have been observed, and these range in atomic mass number from 76 to 108.Sony VAIO VGN-Z56TG/E Battery

The least stable of these is 106Y with a half-life of >150 ns (76Y has a half-life of >200 ns) and the most stable is 88Y with a half-life of 106.626 days.[25] Besides the isotopes 91Y, 87Y, and 90Y, with half-lives of 58.51 days, 79.8 hours, and 64 hours, respectively, all the other isotopes have half-lives of less than a day and most of those have half-lives of less than an hour.Sony VAIO VGN-Z56TG/R Battery

Yttrium isotopes with mass numbers at or below 88 decay primarily by positron emission (proton ? neutron) to form strontium (Z = 38) isotopes. Yttrium isotopes with mass numbers at or above 90 decay primarily by electron emission (neutron ? proton) to form zirconium (Z = 40) isotopes.Sony VAIO VGN-Z570N/B Battery

Isotopes with mass numbers at or above 97 are also known to have minor decay paths of ?? delayed neutron emission.

Yttrium has at least 20 metastable or excited isomers ranging in mass number from 78 to 102. Multiple excitation states have been observed for 80Y and 97Y.Sony VAIO VGN-Z57G Battery

While most of yttrium's isomers are expected to be less stable than their ground state,78mY, 84mY, 85mY, 96mY, 98m1Y, 100mY, and 102mY have longer half-lives than their ground states, as these isomers decay by beta decay rather than isomeric transition.Sony VAIO VGN-Z57GG/X Battery

In 1787, army lieutenant and part-time chemist Carl Axel Arrhenius found a heavy black rock in an old quarry near the Swedish village of Ytterby (now part of theStockholm Archipelago). Thinking that it was an unknown mineral containing the newly discovered element tungsten, he named it ytterbite and sent samples to various chemists for further analysis.Sony VAIO VGN-Z57GGX Battery

Johan Gadolin at the University of Åbo identified a new oxide or "earth" in Arrhenius' sample in 1789, and published his completed analysis in 1794. Anders Gustaf Ekeberg confirmed this in 1797 and named the new oxide yttria. In the decades after Antoine Lavoisierdeveloped the first modern definition of chemical elements,Sony VAIO VGN-Z57TG/X Battery

it was believed that earths could be reduced to their elements, meaning that the discovery of a new earth was equivalent to the discovery of the element within, which in this case would have been yttrium.

In 1843, Carl Gustaf Mosander found that samples of yttria contained three oxides: white yttrium oxide (yttria), yellow terbium oxide(confusingly, this was called 'erbia' at the time) and rose-colored erbium oxide (called 'terbia' at the time).Sony VAIO VGN-Z58GG/X Battery

A fourth oxide,ytterbium oxide, was isolated in 1878 by Jean Charles Galissard de Marignac.[31] New elements would later be isolated from each of those oxides, and each element was named, in some fashion, after Ytterby, the village near the quarry in which they were found (see ytterbium,terbium, and erbium).Sony VAIO VGN-Z58GGX Battery

In the following decades, seven other new metals were discovered in "Gadolin's yttria".[3] Since yttria was a mineral after all and not an oxide, Martin Heinrich Klaproth renamed it gadolinite in honor of Gadolin.[3]

Yttrium metal was first isolated in 1828 when Friedrich Wöhler heated anhydrous yttrium(III) chloride with potassium:Sony VAIO VGN-Z590NJB Battery

YCl3 + 3 K ? 3 KCl + Y

Until the early 1920s, the chemical symbol Yt was used for the element, after which Y came into common use.[35]

In 1987, yttrium barium copper oxide was found to achieve high-temperature superconductivity.Sony VAIO VGN-Z590UAB Battery

It was only the second material known to exhibit this property,[36]and it was the first known material to achieve superconductivity above the (economically important) boiling point of nitrogen.

Abundance

Yttrium is found in most rare earth minerals,[8] as well as some uranium ores, but is never found in nature as a free element.Sony VAIO VGN-Z591U/B Battery

About 31 ppm of the Earth's crust is yttrium,[5] making it the 28th most abundant element there, and 400 times more common thansilver.[38] Yttrium is found in soil in concentrations between 10 and 150 ppm (dry weight average of 23 ppm) and in sea water at 9 ppt.Sony VAIO VGN-Z59G Battery

Lunar rock samples collected during the American Apollo Project have a relatively high content of yttrium.[32]

Yttrium has no known biological role, though it is found in most, if not all, organisms and tends to concentrate in the liver, kidney, spleen, lungs, and bones of humans.Sony VAIO VGN-Z620D Battery

There is normally as little as 0.5 milligrams found within the entire human body; human breast milk contains 4 ppm. Yttrium can be found in edible plants in concentrations between 20 ppm and 100 ppm (fresh weight), with cabbage having the largest amount. With up to 700 ppm, the seeds of woody plants have the highest known concentrations.Sony VAIO VGN-Z620N/B Battery

The chemical similarity of yttrium with the lanthanides leads it to being enriched by the same processes and ends up in ores containing lanthanides, forming rare earth minerals. A slight separation is recognized between the light (LREE) and the heavy rare earth elements (HREE) but this separation is never complete.Sony VAIO VGN-Z650N/B Battery

Yttrium is concentrated in the HREE group even though it has a lower atomic mass.

• Carbonate and fluoride containing ores such as the LREE bastnäsite ([(Ce, La, etc.)(CO3)F]) contain an average of 0.1% of yttrium compared to the 99.9% for the 16 other REEs.Sony VAIO VGN-Z670N/B Battery

• The main source for bastnäsite from the 1960s to the 1990s was theMountain Pass rare earth mine in California, making the United States the largest producer of REEs during that period.
• Monazite ([(Ce, La, etc.)PO4]), which is mostly phosphate, is a placer deposit of sand that is created by the transportation and gravitational separation of eroded granite.Sony VAIO VGN-Z690CTO Battery

• Monazite as a LREE ore contains 2% (or 3%) of yttrium. The largest deposits were found in India and Brazil in the early 19th century, making these two countries the largest producers of yttrium in the first half of that century.
• Xenotime, a REE phosphate, is the main HREE ore containing up to 60% of yttrium as yttrium phosphate (YPO4).Sony VAIO VGN-Z690NAX Battery

• The largest mine for this mineral is the Bayan Obo deposit in China, making China the largest exporter for HREE since the closure of the Mountain Pass mine in the 1990s.
• Ion absorption clays or Lognan clays are the weathering products of granite and contain only 1% of REEs.Sony VAIO VGN-Z690PAB Battery

• The final ore concentrate can contain up to 8% of yttrium. Ion absorption clays are mostly mined in southern China. Yttrium is also found in samarskite and fergusonite.

It is difficult to separate yttrium from other rare earths.Sony VAIO VGN-Z690PCB Battery

One method to obtain pure yttrium from the mixed oxide ores is to dissolve the oxide in sulfuric acid and fractionate it by ion exchange chromatography. With the addition of oxalic acid, the yttrium oxalate precipitates. The oxalate is converted into the oxide by heating under oxygen.Sony VAIO VGN-Z690PDB Battery

By reacting the resulting yttrium oxide withhydrogen fluoride, yttrium fluoride is obtained.

Annual world production of yttrium oxide had reached 600 tonnes by 2001, with reserves estimated at 9 million tonnes. Only a few tonnes of yttrium metal are produced each year by reducing yttrium fluoride to a metal sponge with calcium magnesium alloy.Sony VAIO VGN-Z690PEB Battery

The temperature of an arc furnace of above 1,600 °C is sufficient to melt the yttrium.

Yttria (Y2O3) can serve as host lattice for doping with Eu3+ cations as well as reactant to gain doped yttrium orthovanadateYVO4:Eu3+ or yttrium oxide sulfide Y2O2S:Eu3+ phosphors that give the red color in color television picture tubes,Sony VAIO VGN-Z690PFB Battery

though the red color itself is actually emitted from the europium while the yttrium collects energy from the electron gun and passes it to the phosphor.[47] Yttrium compounds can serve as host lattices for doping with different lanthanide cations. Besides Eu3+also Tb3+ can be used as a doping agent leading to green luminescence.Sony VAIO VGN-Z690YAD Battery

Yttria is also used as a sintering additive in the production of porous silicon nitride[48] and as a common starting material for both material science and for producing other compounds of yttrium.

Yttrium compounds are used as a catalyst for ethylene polymerization.[4] As a metal, it is used on the electrodes of some high-performance spark plugs.Sony VAIO VGN-Z691Y/B Battery

Yttrium is also used in the manufacturing of gas mantles for propane lanterns as a replacement forthorium, which is radioactive.[50]

Developing uses include yttrium-stabilized zirconia in particular as a solid electrolyte and as an oxygen sensor in automobile exhaust systems.Sony VAIO VGN-Z691Y/X Battery

Garnets

Yttrium is used in the production of a large variety of synthetic garnets, and yttria is used to make yttrium iron garnets(Y3Fe5O12 or YIG), which are very effective microwave filters. Yttrium, iron, aluminium, and gadolinium garnets (e.g. Y3(Fe,Al)5O12 and Y3(Fe,Ga)5O12) have important magnetic properties.Sony VAIO VGN-Z698Y/X Battery

YIG is also very efficient as an acoustic energy transmitter and transducer.Yttrium aluminium garnet (Y3Al5O12 or YAG) has a hardness of 8.5 and is also used as a gemstone in jewelry (simulated diamond). Cerium-doped yttrium aluminium garnet (YAG:Ce) crystals are used as phosphors to make whiteLEDs.Sony VAIO VGN-Z699JAB Battery

YAG, yttria, yttrium lithium fluoride (LiYF4), and yttrium orthovanadate (YVO4) are used in combination with dopants such asneodymium, erbium, ytterbium in near-infrared lasers. YAG lasers have the ability to operate at high power and are used for drilling into and cutting metal.Sony VAIO VGN-Z70B Battery

The single crystals of doped YAG are normally produced by the Czochralski process.

Material enhancer

Small amounts of yttrium (0.1 to 0.2%) have been used to reduce the grain sizes of chromium, molybdenum, titanium, andzirconium.Sony VAIO VGN-Z71JB Battery

It is also used to increase the strength of aluminium and magnesium alloys.[4] The addition of yttrium to alloys generally improves workability, adds resistance to high-temperature recrystallization and significantly enhances resistance to high-temperature oxidation (see graphite nodule discussion below).Sony VAIO VGN-Z73FB Battery

Yttrium can be used to deoxidize vanadium and other non-ferrous metals. Yttria is used to stabilize the cubic form of zirconia for use in jewelry.

Yttrium has been studied for possible use as a nodulizer in the making of nodular cast iron which has increased ductility (the graphite forms compact nodules instead of flakes to form nodular cast iron).Sony VAIO VGN-Z790DKX Battery

Yttrium oxide can also be used in ceramic and glass formulas, since it has a high melting point and imparts shock resistance and low thermal expansion characteristics.It is therefore used in camera lenses.

Medical

The radioactive isotope yttrium-90 is used in drugs such as Yttrium Y 90-DOTA-tyr3-octreotide and Yttrium Y 90 ibritumomab tiuxetan for the treatment of variouscancers,Sony VAIO VGN-Z790DMR Battery

including lymphoma, leukemia, ovarian, colorectal, pancreatic, and bone cancers. It works by adhering to monoclonal antibodies, which in turn bind to cancer cells and kill them via intense ?-radiation from the yttrium-90 (see Monoclonal antibody therapy).Sony VAIO VGN-Z790DND Battery

Needles made of yttrium-90, which can cut more precisely than scalpels, have been used to sever pain-transmitting nerves in the spinal cord, and yttrium-90 is also used to carry out radionuclide synovectomy in the treatment of inflamed joints, especially knees, in sufferers of conditions such as rheumatoid arthritis.Sony VAIO VGN-Z820DB Battery

A neodymium-doped yttrium-aluminium-garnet laser has been used in an experimental, robot-assisted radical prostatectomy in canines in an attempt to reduce collateral nerve and tissue damage,[63] whilst the erbium-doped ones are starting to be used in cosmetic skin resurfacing.Sony VAIO VGN-Z820G/B Battery

Superconductors

(YBa2Cu3O7, aka 'YBCO' or '1-2-3') superconductor developed at the University of Alabama and the University of Houston in 1987.This superconductor operated at 93 K, notable because this is above liquid nitrogen's boiling point (77.1 K).Sony VAIO VGN-Z890GLX Battery

As the price of liquid nitrogen is lower than that of liquid helium, which has to be used for the metallic superconductors, the operating costs would decrease.

The actual superconducting material is often written as YBa2Cu3O7–d, where d must be less than 0.7 if the material is to be superconducting.Sony VAIO VGN-Z890GMR Battery

The reason for this is still not clear, but it is known that the vacancies occur only in certain places in the crystal, the copper oxide planes and chains, giving rise to a peculiar oxidation state of the copper atoms, which somehow leads to the superconducting behavior.Sony VAIO VGN-Z898H/X Battery

The theory of low temperature superconductivity has been well understood since the so-called BCS theory was put forward in 1957. It is based on a peculiarity of the interaction between 2 electrons in a crystal lattice. However, BCS theory does not explain high temperature superconductivity, and its precise mechanism is still a mystery.Sony VAIO VGN-Z90FS Battery

What is known is that the composition of the copper-oxide materials has to be precisely controlled if superconductivity is to occur.

The created material was a black and green, multi-crystal, multi-phase mineral. Researchers are studying a class of materials known as perovskites that are alternative mixtures of these elements, hoping to eventually develop a practical high-temperature superconductor.Sony VAIO VGN-Z90NS Battery

Precautions

Water soluble compounds of yttrium are considered mildly toxic, while its insoluble compounds are non-toxic. In experiments on animals, yttrium and its compounds caused lung and liver damage, though toxicity varies with different yttrium compounds.Sony VAIO VGN-Z90PS Battery

In rats, inhalation of yttrium citrate caused pulmonary edema and dyspnea, while inhalation of yttrium chloride caused liver edema, pleural effusions, and pulmonary hyperemia.

Exposure to yttrium compounds in humans may cause lung disease.Sony VAIO VGN-Z90S Battery

Workers exposed to airborne yttrium europium vanadate dust experienced mild eye, skin, and upper respiratory tract irritation—though this may have been caused by the vanadium content rather than the yttrium. Acute exposure to yttrium compounds can cause shortness of breath, coughing, chest pain, and cyanosis.Sony VAIO VGN-Z90US Battery

NIOSH recommends a time-weighted average limit of 1 mg/m3 and an IDLH of 500 mg/m3. Yttrium dust is flammable.

Zirconium is a chemical element with the symbol Zr and atomic number 40. The name of zirconium is taken from the mineral zircon. Its atomic mass is 91.224. Sony VAIO VGN-Z91DS Battery

It is a lustrous, gray-white, strong transition metalthat resembles titanium. Zirconium is mainly used as a refractory and opacifier, although minor amounts are used as alloying agent for its strong resistance to corrosion. Zirconium is obtained mainly from the mineral zircon, which is the most important form of zirconium in use.Sony VAIO VGN-Z91JS Battery

Zirconium forms a variety of inorganic and organometallic compounds such as zirconium dioxide and zirconocene dichloride, respectively. Five isotopes occur naturally, three of which are stable. Zirconium compounds have no biological role.

Characteristics

Zirconium is a lustrous, grayish-white, soft, ductile and malleable metal which is solid at room temperature, though it becomes hard and brittle at lower purities.Sony VAIO VGN-Z91PS Battery

In powder form, zirconium is highly flammable, but the solid form is far less prone to ignition. Zirconium is highly resistant to corrosion by alkalies, acids, salt water and other agents.[6]However, it will dissolve in hydrochloric and sulfuric acid, especially when fluorine is present. Alloys with zinc become magnetic below 35 K.Sony VAIO VGN-Z91YS Battery

Zirconium's melting point is 1855 °C (3371 °F), and its boiling point is 4371 °C (7900 °F).[6] Zirconium has anelectronegativity of 1.33 on the Pauling scale. Of the elements within d-block, zirconium has the fourth lowest electronegativity after yttrium, lutetium and hafnium.Sony VAIO VGN-Z92DS Battery

ZrZn2 is one of only two substances to exhibit superconductivity and ferromagnetism simultaneously, with the other being UGe2.

Naturally occurring zirconium is composed of five isotopes. 90Zr, 91Zr, 92Zr and 94Zr are stable. 94Zr can undergo double beta decay (not observed experimentally) with a half-life of more than 1.10×1017 years.Sony VAIO VGN-Z92JS Battery

96Zr has a half-life of 2.4×1019 years, making it the longest-lived radioisotope of zirconium. Of these natural isotopes, 90Zr is the most common, making up 51.45% of all zirconium. 96Zr is the least common, comprising only 2.80% of zirconium.

Twenty-eight artificial isotopes of zirconium have been synthesized, ranging in atomic mass from 78 to 110.Sony VAIO VGN-Z92PS Battery

93Zr is the longest-lived artificial isotope, with a half-life of 1.53×106 years. 110Zr, the heaviest isotope of zirconium, is also the shortest-lived, with an estimated half-life of only 30 milliseconds. Radioactive isotopes at or above mass number 93 decay by ??, whereas those at or below 89 decay by ?+. The only exception is 88Zr, which decays by ?.Sony VAIO VGN-Z92YS Battery

Five isotopes of zirconium also exist as metastable isomers: 83mZr, 85mZr, 89mZr, 90m1Zr, 90m2Zr and 91mZr. Of these, 90m2Zr has the shortest half-life at 131 nanoseconds. 89mZr is the longest lived with a half-life of 4.161 minutes.

Zirconium has a concentration of about 130 mg/kg within the earth's crust and about 0.026 ?g/L in sea water.Sony VAIO VGN-Z93FS Battery

It is not found in nature as a native metal, reflecting its intrinsic instability with respect to water. The principal commercial source of zirconium is the silicate mineral, zircon (ZrSiO4), which is found primarily in Australia, Brazil, India, Russia, South Africa and the United States, as well as in smaller deposits around the world.Sony VAIO VGN-Z93GS Battery

80% of zircon mining occurs in Australia and South Africa. Zircon resources exceed 60 million metric tons worldwide and annual worldwide zirconium production is approximately 900,000 metric tons.Zirconium also occurs in more than 140 other minerals, including the commercially useful ores baddeleyite and kosnarite.Sony VAIO VGN-Z93HS Battery

Zr is relatively abundant in S-type stars, and it has been detected in the sun and in meteorites. Lunar rock samples brought back from several Apollo program missions to the moon have a quite high zirconium oxide content relative to terrestrial rocks.

Zircon is a by-product of the mining and processing of the titanium minerals ilmenite and rutile, as well as tin mining.Sony A1258274A Battery

From 2003 to 2007, zircon prices have steadily increased from $360 to $840 per metric ton.

Upon being collected from coastal waters, zircon-containing sand is purified by spiral concentrators to remove lighter materials, which are then placed back into the water safely, as they are all natural components of beach sand. Using magnetic separators, the titanium ores ilmenite and rutile are removed.Sony VGP-BPL10 Battery

Most zircon is used directly in commercial applications, but a few percent is converted to the metal. Most Zr metal is produced by the reduction of the zirconium(IV) chloride with magnesium metal in the Kroll process.[6] Commercial-quality zirconium for most uses still has a content of 1% to 3% hafnium.Sony VGP-BPS10 Battery

This contaminant is unimportant except in nuclear applications. The resulting metal is sintered until sufficiently ductile for metalworking.

Separation of Zr and Hf

Commercial zirconium metal typically contains 1–2.5% of hafnium, which is not problematic because the chemical properties of hafnium and zirconium are rather similar.Sony VGP-BPS10/S Battery

Their neutron-absorbing properties differ strongly, however, necessitating the separation of hafnium from zirconium for applications involving nuclear reactors. Several separation schemes are in use. The liquid-liquid extraction of the thiocyanate-oxide derivatives, exploits the slightly greater solubility of the hafnium derivative in methyl isobutyl ketone vs water.Sony VGP-BPS10A/B Battery

This method is used mainly in United States. Zr and Hf can also be separated by fractional crystallization of potassium hexafluorozirconate (K2ZrF6), which is less soluble in water than the analogous hafnium derivative. Fractional distillation of the tetrachlorides, also called extractive distillation, is used primarily in Europe.Sony VGP-BPS10B Battery

A quadruple VAM (vacuum arc melting) process, combined with hot extruding and different rolling applications is cured using high-pressure high-temperature gas autoclaving, resulting in reactor-grade zirconium that is about 10 times more expensive than the hafnium-contaminated commercial grade.Sony VGP-BPS10A Battery

The separated hafnium can be used for control rods of the reactor.[17] The separation of hafnium is especially important for nuclear applications since Hf has very high neutron absorption cross-section, 600 times higher than zirconium, and therefore has to be removed for reactor applications.Sony VGP-BPS11 Battery

Compounds

Like other transition metals, zirconium forms a wide range of inorganic compounds and coordination complexes.[19] In general, these compounds are colourless diamagnetic solids wherein Zr has the oxidation state IV+. Far fewer Zr(III) compounds are known, and Zr(II) is very rare.Sony VGP-BPL11 Battery

Oxides, nitrides and carbides

The most common oxide is zirconium dioxide, ZrO2, also referred to as zirconia. This colourless solid has exceptionalfracture toughness and chemical resistance, especially in its cubic form.These properties make zirconia useful as a thermal barrier coating,although it is also a common diamond substitute.Sony VGP-BPL12 Battery

Zirconium tungstate is an unusual substance in that it shrinks in all directions when heated, whereas most other substances expand when heated.[6] Zirconyl chloride is a rare water-soluble zirconium complex, it has the relatively complicated formula [Zr4(OH)12(H2O)16]Cl8.Sony VGP-BPS12 Battery

Zirconium carbide and zirconium nitride are refractory solids. The carbide is used to make drilling tools and cutting edges. Zirconium(II) hydride is also known.

Halides and pseudohalides

All four common halides are known, ZrF4 ZrCl4, ZrBr4 and ZrI4. All have polymeric structures and are far less volatile than the corresponding monomeric titanium tetrahalides.Sony VGP-BPL13 Battery

All tend to hydrolyse to give the so-called oxyhalides and dioxides. The corresponding tetraalkoxides are also known. Unlike the halides, the alkoxides dissolve in nonpolar solvents.

Organic derivatives

Organozirconium chemistry is the study of compounds containing a carbon-zirconium bond.Sony VGP-BPS13 Battery

The first such compound was zirconocene dibromide ((C5H5)2ZrBr2), reported in 1952 by Birmingham and Wilkinson. Schwartz's reagent, prepared in 1970 by P. C. Wailes and H. Weigold, is a metallocene used in organic synthesis for transformations of alkenes and alkynes.Sony VGP-BPS13/B Battery

Zirconium is also a component of some Ziegler-Natta catalysts, used to produce polypropylene. This application exploits the ability of zirconium to reversibly form bonds to carbon. Most complexes of Zr(II) are derivatives of zirconacene, one example being (C5Me5)2Zr(CO)2.Sony VGP-BPS13/S Battery

The zirconium-containing mineral zircon and related minerals (jargoon, hyacinth, jacinth, ligure) were mentioned in biblical writings.The mineral was not known to contain a new element until 1789,when Klaproth analyzed a jargoon from the island of Ceylon (now Sri Lanka). He named the new element Zirkonerde (zirconia).Sony VGP-BPS13/S Battery

Humphry Davy attempted to isolate this new element in 1808 through electrolysis, but failed.[4] Zirconium metal was first obtained in an impure form in 1824 by Berzelius by heating a mixture of potassium and potassium zirconium fluoride in an iron tube.Sony VGP-BPS13A/B Battery

The crystal bar process (also known as the Iodide Process), discovered by Anton Eduard van Arkel andJan Hendrik de Boer in 1925, was the first industrial process for the commercial production of metallic zirconium. The process involves the formation and subsequent thermal decomposition ofzirconium tetraiodide.Sony VGP-BPS13A/S Battery

This method was superseded in 1945 by the much cheaper Kroll process developed by William Justin Kroll, in which zirconium tetrachloride is reduced by magnesium:

ZrCl4 + 2 Mg ? Zr + 2 MgCl2

Applications

Approximately 900,000 tons of Zr ores were produced commercially in 1995, mostly as zircon.Sony VGP-BPS13AS Battery

Zirconium compounds

The great majority of zircon is used directly in a variety of high temperature applications. This material is refractory and hard, as well as resistant to chemical attack. Because of these properties, zircon finds many applications, few of which are highly publicized.Sony VGP-BPS13B/B Battery

Its main use is as an opacifier, conferring a white, opaque appearance to decorative ceramic materials. Because of its chemical resistance, zircon is also used in aggressive environments, such as moulds for molten metals. Zirconium dioxide (ZrO2) is used in laboratory crucibles,Sony VGP-BPS13B/Q Battery

metallurgical furnaces, as a refractory material, and it can besintered into a ceramic knife. Zircon (ZrSiO4) is cut into gemstones for use in jewelry.

Zirconium metal

A small fraction of the zircon is converted to the metal, which finds various niche applications.Sony VGP-BPS13B/S Battery

Because of zirconium's excellent resistance to corrosion, it is often used as an alloying agent in materials that are exposed to aggressive environments, such as surgical appliances and light filaments. The high reactivity of zirconium toward oxygen, apparent only at high temperatures, is the basis of some specialised applications as explosive primers and as getters in vacuum tubes.Sony VGP-BPS13Q Battery

The same behavior is probably the basis of the use of Zr nano-particles as pyrophoric material in explosive weapons such as the BLU-97/B Combined Effects Bomb for incendiary effect.

Nuclear applications

Consuming about 1% of the Zr supply, zirconium is used for cladding nuclear reactor fuels.Sony VGP-BPS13S Battery

For this purpose, it is mainly used in the form of zircaloys. The benefits of Zr alloys is their low neutron-capture cross-section and good resistance to corrosion under normal service conditions.The development of efficient methods for the separation of zirconium from hafnium was required for this application.Sony VGP-BPL7 Battery

One disadvantage of zirconium alloys is their reactivity toward water at high temperatures leading to the formation of hydrogen gas and to the accelerated degradation of the fuel rod cladding:

Zr + 2 H2O ? ZrO2 + 2 H2

This exothermic reaction is very slow below 100 °C, but at temperature above 900 °C the reaction becomes rapid and is proportional to the square of mass of metal available.Sony VGP-BPS7 Battery

Most metals undergo similar reactions, such as e.g. iron whose reaction with water steam inside an incandescent tube was used by Antoine Lavoisier to produce hydrogen. The redox reaction is relevant to the instability of fuel assemblies at high temperatures,Sony VGP-BPL8 Battery

This reaction was responsible for a small hydrogen explosion first observed inside the reactor building of Three Mile Island accidented nuclear power plant in 1979, but then, the containment building was not damaged.Sony VGP-BPL8A Battery

The same reaction occurred in the reactors 1, 2 and 3 of the Fukushima I Nuclear Power Plant (Japan) and in the spent fuel pool of reactor 4 after the reactors cooling was interrupted by the earthquake and tsunami disaster of March 11, 2011 leading to the Fukushima I nuclear accidents.Sony VGP-BPL8B Battery

After venting of hydrogen in the maintenance hall of these three reactors, the explosive mixture of hydrogen with air oxygen detonated, severely damaging the installations and at least one of the containment buildings. To avoid explosion, the direct venting of hydrogen to the open atmosphere would have been a preferred design option.Sony VGP-BPS8 Battery

Now, to prevent the risk of explosion in many pressurized water reactor (PWR) containment buildings, a catalyst-based recombinator is installed to rapidly convert hydrogen and oxygen into water at room temperature before explosivity limit is reached.Sony VGP-BPS8A Battery

Space and aeronautic industries

Materials fabricated from zirconium metal and its oxide (ZrO2) are used in space vehicle parts for their resistance to heat. Zirconia is also a component in someabrasives, such as grinding wheels and sandpaper.Sony VGP-BPS8B Battery

High temperature parts such as combustors, blades and vanes in jet engines and stationary gas turbines are to an increasing extent being protected by thin ceramiclayers. These ceramic layers are usually composed by a mixture of zirconia and yttria.

Zirconium in positron emission tomography (PET) cameras

The isotope 89Zr has been recently applied to the tracking and quantification of molecular antibodies with positron emission tomography (PET) cameras (a method called "immuno-PET").Sony VGP-BPL9 Battery

Immuno-PET has reached maturity in terms of technical development and is now entering the phase of wide-scale clinical applications.Until recently, radiolabeling with 89Zr was a complicated procedure requiring multiple steps.Sony VGP-BPS9 Battery

In 2001–2003 an improved multistep procedure was developed using a succinylated derivative of desferrioxamine B (N-sucDf) as a bifunctional chelate, and a better way of binding 89Zr to mAbs was reported in 2009. The new method is fast, consists of only two steps, and uses two widely available ingredients: 89Zr and the appropriate chelate.Sony VGP-BPS9/B Battery

Defunct applications

Zirconium carbonate (3ZrO2·CO2·H2O) was used in lotions to treat poison ivy but was discontinued because it occasionally caused bad skin reactions.

Safety

Zirconium has no known biological role, and zirconium compounds are of low toxicity.Sony VGP-BPS9/S Battery

The human body contains, on average, only 1 milligram of zirconium, and daily intake is approximately 50 ?g per day. Zirconium content in human blood is as low as 10 parts per billion. Aquatic plants readily take up soluble zirconium, but it is rare in land plants. 70% of plants have no detectable zirconium content, and those that do have as little as 5 parts per billion.Sony VGP-BPS9A Battery

Short-term exposure to zirconium powder can cause irritation, but only contact with the eyes requires medical attention. Inhalation of zirconium compounds can cause skin and lung granulomas. Zirconium aerosols can cause pulmonary granulomas.Sony VGP-BPS9A/B Battery

Persistent exposure to zirconium tetrachloride resulted in increased mortality in rats and guinea pigs and a decrease of blood hemoglobin and red blood cell in dogs. The U.S. Occupational Safety and Health Administration recommends a 5 mg/m3 time weighted average limit and a 10 mg/m3 short-term exposure limit for air dust.Sony VGP-BPS9A/S Battery,Sony VGP-BPS9B Battery,Sony VGP-BPX11 Battery,Sony VGP-BPL18 Battery,Sony VGP-BPS18 Battery,Sony VGP-BPL20 Battery,Sony VGP-BPS20/B Battery,Sony VGP-BPS20/S Battery