Strontium

Last updated

Strontium, 38Sr
Strontium destilled crystals.jpg
Strontium
Pronunciation
Appearancesilvery white metallic; with a pale yellow tint [1]
Standard atomic weight Ar°(Sr)
Strontium 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
Ca
↑
Sr
↓
Ba
rubidium ← strontium → yttrium
Atomic number (Z)38
Group group 2 (alkaline earth metals)
Period period 5
Block   s-block
Electron configuration [ Kr ] 5s2
Electrons per shell2, 8, 18, 8, 2 [4]
Physical properties
Phase at  STP solid
Melting point 1050  K ​(777 °C,​1431 °F)
Boiling point 1650 K​(1377 °C,​2511 °F)
Density (at 20° C)2.582 g/cm3 [5]
when liquid (at  m.p.)2.375 g/cm3
Heat of fusion 7.43  kJ/mol
Heat of vaporization 141 kJ/mol
Molar heat capacity 26.4 J/(mol·K)
Vapor pressure
P (Pa)1101001 k10 k100 k
at T (K)796882990113913451646
Atomic properties
Oxidation states common: +2
+1 [6]
Electronegativity Pauling scale: 0.95
Ionization energies
  • 1st: 549.5 kJ/mol
  • 2nd: 1064.2 kJ/mol
  • 3rd: 4138 kJ/mol
Atomic radius empirical:215  pm
Covalent radius 195±10 pm
Van der Waals radius 249 pm
Strontium spectrum visible.png
Spectral lines of strontium
Other properties
Natural occurrence primordial
Crystal structure ​ face-centered cubic (fcc)(cF4)
Lattice constant
Cubic-face-centered.svg
a = 608.6 pm (at 20 °C) [5]
Thermal expansion 22.55×10−6/K (at 20 °C) [5]
Thermal conductivity 35.4 W/(m⋅K)
Electrical resistivity 132 nΩ⋅m(at 20 °C)
Magnetic ordering paramagnetic
Molar magnetic susceptibility −92.0×10−6 cm3/mol(298 K) [7]
Young's modulus 15.7 GPa
Shear modulus 6.03 GPa
Poisson ratio 0.28
Mohs hardness 1.5
CAS Number 7440-24-6
History
Namingafter the mineral strontianite, itself named after Strontian, Scotland
Discovery William Cruickshank (1787)
First isolation Humphry Davy (1808)
Isotopes of strontium
Main isotopes [8] Decay
abun­dance half-life (t1/2) mode pro­duct
82Sr synth 25.36 d ε 82Rb
83Srsynth1.35 dε 83Rb
β+ 83Rb
γ –
84Sr0.56% stable
85Srsynth64.84 dε 85Rb
γ–
86Sr9.86%stable
87Sr7%stable
88Sr82.6%stable
89Srsynth50.52 d β− 89Y
90Sr trace 28.90 yβ− 90Y
Symbol category class.svg  Category: Strontium
| references

Strontium is a chemical element; it has symbol Sr and atomic number 38. An alkaline earth metal, strontium is a soft silver-white yellowish metallic element that is highly chemically reactive. The metal forms a dark oxide layer when it is exposed to air. Strontium has physical and chemical properties similar to those of its two vertical neighbors in the periodic table, calcium and barium. It occurs naturally mainly in the minerals celestine and strontianite, and is mostly mined from these.

Contents

Both strontium and strontianite are named after Strontian, a village in Scotland near which the mineral was discovered in 1790 by Adair Crawford and William Cruickshank; it was identified as a new element the next year from its crimson-red flame test color. Strontium was first isolated as a metal in 1808 by Humphry Davy using the then newly discovered process of electrolysis. During the 19th century, strontium was mostly used in the production of sugar from sugar beets (see strontian process). At the peak of production of television cathode-ray tubes, as much as 75% of strontium consumption in the United States was used for the faceplate glass. [9] With the replacement of cathode-ray tubes with other display methods, consumption of strontium has dramatically declined. [9]

While natural strontium (which is mostly the isotope strontium-88) is stable, the synthetic strontium-90 is radioactive and is one of the most dangerous components of nuclear fallout, as strontium is absorbed by the body in a similar manner to calcium. Natural stable strontium, on the other hand, is not hazardous to health.

Characteristics

Oxidized dendritic strontium Strontium 1.jpg
Oxidized dendritic strontium

Strontium is a divalent silvery metal with a pale yellow tint whose properties are mostly intermediate between and similar to those of its group neighbors calcium and barium. [10] It is softer than calcium and harder than barium. Its melting (777 °C) and boiling (1377 °C) points are lower than those of calcium (842 °C and 1484 °C respectively); barium continues this downward trend in the melting point (727 °C), but not in the boiling point (1900 °C). The density of strontium (2.64 g/cm3) is similarly intermediate between those of calcium (1.54 g/cm3) and barium (3.594 g/cm3). [11] Three allotropes of metallic strontium exist, with transition points at 235 and 540 °C.[ citation needed ]

The standard electrode potential for the Sr2+/Sr couple is −2.89 V, approximately midway between those of the Ca2+/Ca (−2.84 V) and Ba2+/Ba (−2.92 V) couples, and close to those of the neighboring alkali metals. [12] Strontium is intermediate between calcium and barium in its reactivity toward water, with which it reacts on contact to produce strontium hydroxide and hydrogen gas. Strontium metal 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 forms only the oxide spontaneously. [11] Besides the simple oxide SrO, the peroxide SrO2 can be made by direct oxidation of strontium metal under a high pressure of oxygen, and there is some evidence for a yellow superoxide Sr(O2)2. [13] Strontium hydroxide, Sr(OH)2, is a strong base, though it is not as strong as the hydroxides of barium or the alkali metals. [14] All four dihalides of strontium are known. [15]

Due to the large size of the heavy s-block elements, including strontium, a vast range of coordination numbers is known, from 2, 3, or 4 all the way to 22 or 24 in SrCd11 and SrZn13. The Sr2+ ion is quite large, so that high coordination numbers are the rule. [16] The large size of strontium and barium plays a significant part in stabilising strontium complexes with polydentate macrocyclic ligands such as crown ethers: for example, while 18-crown-6 forms relatively weak complexes with calcium and the alkali metals, its strontium and barium complexes are much stronger. [17]

Organostrontium compounds contain one or more strontium–carbon bonds. They have been reported as intermediates in Barbier-type reactions. [18] [19] [20] Although strontium is in the same group as magnesium, and organomagnesium compounds are very commonly used throughout chemistry, organostrontium compounds are not similarly widespread because they are more difficult to make and more reactive. Organostrontium compounds tend to be more similar to organoeuropium or organosamarium compounds due to the similar ionic radii of these elements (Sr2+ 118 pm; Eu2+ 117 pm; Sm2+ 122 pm). Most of these compounds can only be prepared at low temperatures; bulky ligands tend to favor stability. For example, strontium dicyclopentadienyl, Sr(C5H5)2, must be made by directly reacting strontium metal with mercurocene or cyclopentadiene itself; replacing the C5H5 ligand with the bulkier C5(CH3)5 ligand on the other hand increases the compound's solubility, volatility, and kinetic stability. [21]

Because of its extreme reactivity with oxygen and water, strontium occurs naturally only in compounds with other elements, such as in the minerals strontianite and celestine. It is kept under a liquid hydrocarbon such as mineral oil or kerosene to prevent oxidation; freshly exposed strontium metal rapidly turns a yellowish color with the formation of the oxide. Finely powdered strontium metal is pyrophoric, meaning that it will ignite spontaneously in air at room temperature. Volatile strontium salts impart a bright red color to flames, and these salts are used in pyrotechnics and in the production of flares. [11] Like calcium and barium, as well as the alkali metals and the divalent lanthanides europium and ytterbium, strontium metal dissolves directly in liquid ammonia to give a dark blue solution of solvated electrons. [10]

Isotopes

Natural strontium is a mixture of four stable isotopes: 84Sr, 86Sr, 87Sr, and 88Sr. [11] On these isotopes, 88Sr is the most abundant, makes up about 82.6% of all natural strontium, though the abundance varies due to the production of radiogenic 87Sr as the daughter of long-lived beta-decaying 87 Rb. [22] This is the basis of rubidium–strontium dating. Of the unstable isotopes, the primary decay mode of the isotopes lighter than 85Sr is electron capture or positron emission to isotopes of rubidium, and that of the isotopes heavier than 88Sr is electron emission to isotopes of yttrium. Of special note are 89Sr and 90Sr. The former has a half-life of 50.6 days and is used to treat bone cancer due to strontium's chemical similarity and hence ability to replace calcium. [23] [24] While 90Sr (half-life 28.90 years) has been used similarly, it is also an isotope of concern in fallout from nuclear weapons and nuclear accidents due to its production as a fission product. Its presence in bones can cause bone cancer, cancer of nearby tissues, and leukemia. [25] The 1986 Chernobyl nuclear accident contaminated about 30,000 km2 with greater than 10 kBq/m2 with 90Sr, which accounts for about 5% of the 90Sr which was in the reactor core. [26]

History

Flame test for strontium FlammenfarbungSr.png
Flame test for strontium

Strontium is named after the Scottish village of Strontian (Scottish Gaelic : Sròn an t-Sìthein), where it was discovered in the ores of the lead mines. [27]

In 1790, Adair Crawford, a physician engaged in the preparation of barium, and his colleague William Cruickshank, recognised that the Strontian ores exhibited properties that differed from those in other "heavy spars" sources. [28] This allowed Crawford to conclude on page 355 "... it is probable indeed, that the scotch mineral is a new species of earth which has not hitherto been sufficiently examined." The physician and mineral collector Friedrich Gabriel Sulzer analysed together with Johann Friedrich Blumenbach the mineral from Strontian and named it strontianite. He also came to the conclusion that it was distinct from the witherite and contained a new earth (neue Grunderde). [29] In 1793 Thomas Charles Hope, a professor of chemistry at the University of Glasgow studied the mineral [30] [31] and proposed the name strontites. [32] [33] [34] 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." The element was eventually isolated by Sir Humphry 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. [35] In keeping with the naming of the other alkaline earths, he changed the name to strontium. [36] [37] [38] [39] [40]

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 [41] the large scale introduction came with the improvement of the process in the early 1870s. The German sugar industry used the process well into the 20th century. Before World War I the beet sugar industry used 100,000 to 150,000 tons of strontium hydroxide for this process per year. [42] 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. The mining of strontianite in Germany ended when mining of the celestine deposits in Gloucestershire started. [43] These mines supplied most of the world strontium supply from 1884 to 1941. Although the celestine deposits in the Granada basin were known for some time the large scale mining did not start before the 1950s. [44]

During atmospheric nuclear weapons testing, it was observed that strontium-90 is one of the nuclear fission products with a relatively high yield. The similarity to calcium and the chance that the strontium-90 might become enriched in bones made research on the metabolism of strontium an important topic. [45] [46]

Occurrence

The mineral celestine (SrSO4) Celestine Poland.jpg
The mineral celestine (SrSO4)

Strontium commonly occurs in nature, being the 15th most abundant element on Earth (its heavier congener barium being the 14th), estimated to average approximately 360  parts per million in the Earth's crust [47] and is found chiefly as the sulfate mineral celestine (SrSO4) and the carbonate strontianite (SrCO3). Of the two, celestine occurs much more frequently in deposits of sufficient size for mining. Because strontium is used most often in the carbonate form, strontianite would be the more useful of the two common minerals, but few deposits have been discovered that are suitable for development. [48] Because of the way it reacts with air and water, strontium only exists in nature when combined to form minerals. Naturally occurring strontium is stable, but its synthetic isotope Sr-90 is only produced by nuclear fallout.

In groundwater strontium behaves chemically much like calcium. At intermediate to acidic pH Sr2+ is the dominant strontium species. In the presence of calcium ions, strontium commonly forms coprecipitates with calcium minerals such as calcite and anhydrite at an increased pH. At intermediate to acidic pH, dissolved strontium is bound to soil particles by cation exchange. [49]

The mean strontium content of ocean water is 8 mg/L. [50] [51] At a concentration between 82 and 90 μmol/L of strontium, the concentration is considerably lower than the calcium concentration, which is normally between 9.6 and 11.6 mmol/L. [52] [53] It is nevertheless much higher than that of barium, 13 μg/L. [11]

Production

The major producers of strontium as celestine as of January 2024 are Spain (200,000  t), Iran (200,000 t), China (80,000 t), Mexico (35,000 t); and Argentina (700 t). [54] Although strontium deposits occur widely in the United States, they have not been mined since 1959. [54]

A large proportion of mined celestine (SrSO4) is converted to the carbonate by two processes. Either the celestine is directly leached with sodium carbonate solution or the celestine is roasted with coal to form the sulfide. The second stage produces a dark-coloured material containing mostly strontium sulfide. This so-called "black ash" is dissolved in water and filtered. Strontium carbonate is precipitated from the strontium sulfide solution by introduction of carbon dioxide. [55] The sulfate is reduced to the sulfide by the carbothermic reduction:

SrSO4 + 2 C → SrS + 2 CO2

About 300,000 tons are processed in this way annually. [56]

The metal is produced commercially by reducing strontium oxide with aluminium. The strontium is distilled from the mixture. [56] Strontium metal can also be prepared on a small scale by electrolysis of a solution of strontium chloride in molten potassium chloride: [12]

Sr2+ + 2
e−
 → Sr
2 Cl− → Cl2 + 2
e−

Applications

Most of the world's production of strontium used to be consumed in the production of cathode-ray tube (CRT) displays. The glass contained strontium and barium oxide to block X-rays. Monitor.arp.jpg
Most of the world's production of strontium used to be consumed in the production of cathode-ray tube (CRT) displays. The glass contained strontium and barium oxide to block X-rays.

Consuming 75% of production, the primary use for strontium was in glass for colour television cathode-ray tubes, [56] where it prevented X-ray emission. [57] [58] This application for strontium has been declining because CRTs are being replaced by other display methods. This decline has a significant influence on the mining and refining of strontium. [48] All parts of the CRT must 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. Therefore, the front panel is made from a different glass mixture with strontium and barium to absorb the X-rays. The average values for the glass mixture determined for a recycling study in 2005 is 8.5% strontium oxide and 10% barium oxide. [59]

Because strontium is so similar to calcium, it is incorporated in the bone. All four stable isotopes are incorporated, in roughly the same proportions they are found in nature. 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. [60] [61] This approach helps to identify the ancient migration patterns and the origin of commingled human remains in battlefield burial sites. [62]

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 terrains from adjacent landmasses. [63] A good example of a fluvial-marine system to which Sr isotope provenance studies have been successfully employed is the River Nile-Mediterranean system. [64] 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 strontium isotopic studies. Such changes are climatically controlled in the Late Quaternary. [64]

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. [65] [66] 87Sr/86Sr ratios in teeth may also be used to track animal migrations. [67] [68]

Strontium aluminate is frequently used in glow in the dark toys, as it is chemically and biologically inert. [69]

Strontium salts are added to fireworks in order to create red colors. Ignis Brunensis 2010-05-22 (5).jpg
Strontium salts are added to fireworks in order to create red colors.

Strontium carbonate and other strontium salts are added to fireworks to give a deep red colour. [70] This same effect identifies strontium cations in the flame test. Fireworks consume about 5% of the world's production. [56] Strontium carbonate is used in the manufacturing of hard ferrite magnets. [71] [72]

Strontium chloride is sometimes used in toothpastes for sensitive teeth. One popular brand includes 10% total strontium chloride hexahydrate by weight. [73] Small amounts are used in the refining of zinc to remove small amounts of lead impurities. [11] The metal itself has a limited use as a getter, to remove unwanted gases in vacuums by reacting with them, although barium may also be used for this purpose. [12]

The ultra-narrow optical transition between the [Kr]5s21S0 electronic ground state and the metastable [Kr]5s5p 3P0 excited state of 87Sr is one of the leading candidates for the future re-definition of the second in terms of an optical transition as opposed to the current definition derived from a microwave transition between different hyperfine ground states of 133Cs. [74] Current optical atomic clocks operating on this transition already surpass the precision and accuracy of the current definition of the second. [75]

Radioactive strontium

RTGs from Soviet-era lighthouses Soviet RTG.jpg
RTGs from Soviet-era lighthouses

89Sr is the active ingredient in Metastron, [76] a radiopharmaceutical used for bone pain secondary to metastatic bone cancer. The strontium is processed like calcium by the body, preferentially incorporating it into bone at sites of increased osteogenesis. This localization focuses the radiation exposure on the cancerous lesion. [24]

90Sr has been used as a power source for radioisotope thermoelectric generators (RTGs). 90Sr produces approximately 0.93 watts of heat per gram (it is lower for the form of 90Sr used in RTGs, which is strontium fluoride). [77] However, 90Sr has one third the lifetime and a lower density than 238Pu, another RTG fuel. The main advantage of 90Sr is that it is significantly cheaper than 238Pu and is found in nuclear waste. The latter must be prepared by irradiating 237Np with neutrons then separating the modest amounts of 238Pu. The principal disadvantage of 90Sr is the high energy beta particles produce Bremsstrahlung as they encounter nuclei of other nearby heavy atoms such as adjacent strontium. This is mostly in the range of X-rays. Thus strong beta emitters also emit significant secondary X-rays in most cases. This requires significant shielding measures which complicates the design of RTGs using 90Sr. The Soviet Union deployed nearly 1000 of these RTGs on its northern coast as a power source for lighthouses and meteorology stations. [78] [79]

Biological role

Strontium
Hazards
GHS labelling:
GHS-pictogram-flamme.svg GHS-pictogram-exclam.svg
Danger
H261, H315
P223, P231+P232, P370+P378, P422 [80]
NFPA 704 (fire diamond)
NFPA 704.svgHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 0: Will not burn. E.g. waterInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazard W: Reacts with water in an unusual or dangerous manner. E.g. sodium, sulfuric acid
2
0
2
W

Acantharea, a relatively large group of marine radiolarian protozoa, produce intricate mineral skeletons composed of strontium sulfate. [81] In biological systems, calcium is substituted to a small extent by strontium. [82] In the human body, most of the absorbed strontium is deposited in the bones. The ratio of strontium to calcium in human bones is between 1:1000 and 1:2000, roughly in the same range as in the blood serum. [83]

Effect on the human body

The human body absorbs strontium as if it were its lighter congener calcium. Because the elements are chemically very similar, stable strontium isotopes do not pose a significant health threat. The average human has an intake of about two milligrams of strontium a day. [84] In adults, strontium consumed tends to attach only to the surface of bones, but in children, strontium can replace calcium in the mineral of the growing bones and thus lead to bone growth problems. [85]

The biological half-life of strontium in humans has variously been reported as from 14 to 600 days, [86] [87] 1,000 days, [88] 18 years, [89] 30 years [90] and, at an upper limit, 49 years. [91] The wide-ranging published biological half-life figures are explained by strontium's complex metabolism within the body. However, by averaging all excretion paths, the overall biological half-life is estimated to be about 18 years. [92] The elimination rate of strontium is strongly affected by age and sex, due to differences in bone metabolism. [93]

The drug strontium ranelate aids bone growth, increases bone density, and lessens the incidence of vertebral, peripheral, and hip fractures. [94] [95] However, strontium ranelate also increases the risk of venous thromboembolism, pulmonary embolism, and serious cardiovascular disorders, including myocardial infarction. Its use is therefore now restricted. [96] Its beneficial effects are also questionable, since the increased bone density is partially caused by the increased density of strontium over the calcium which it replaces. Strontium also bioaccumulates in the body. [97] Despite restrictions on strontium ranelate, strontium is still contained in some supplements. [98] [99] There is not much scientific evidence on risks of strontium chloride when taken by mouth. Those with a personal or family history of blood clotting disorders are advised to avoid strontium. [98] [99]

Strontium has been shown to inhibit sensory irritation when applied topically to the skin. [100] [101] Topically applied, strontium has been shown to accelerate the recovery rate of the epidermal permeability barrier (skin barrier). [102]

Nuclear waste

Strontium-90 is a radioactive fission product produced by nuclear reactors used in nuclear power. It is a major component of high level radioactivity of nuclear waste and spent nuclear fuel. Its 29-year half life is short enough that its decay heat has been used to power arctic lighthouses, but long enough that it can take hundreds of years to decay to safe levels. Exposure from contaminated water and food may increase the risk of leukemia, bone cancer [103] and primary hyperparathyroidism. [104]

Remediation

Algae has shown selectivity for strontium in studies, where most plants used in bioremediation have not shown selectivity between calcium and strontium, often becoming saturated with calcium, which is greater in quantity and also present in nuclear waste. [103]

Researchers have looked at the bioaccumulation of strontium by Scenedesmus spinosus (algae) in simulated wastewater. The study claims a highly selective biosorption capacity for strontium of S. spinosus, suggesting that it may be appropriate for use in treating nuclear wastewater. [105]

A study of the pond alga Closterium moniliferum using non-radioactive strontium found that varying the ratio of barium to strontium in water improved strontium selectivity. [103]

See also

Related Research Articles

<span class="mw-page-title-main">Barium</span> Chemical element with atomic number 56 (Ba)

Barium is a chemical element; it has symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element.

<span class="mw-page-title-main">Calcium</span> Chemical element with atomic number 20 (Ca)

Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and the third most abundant metal, after iron and aluminium. The most common calcium compound on Earth is calcium carbonate, found in limestone and the fossilised remnants of early sea life; gypsum, anhydrite, fluorite, and apatite are also sources of calcium. The name derives from Latin calx "lime", which was obtained from heating limestone.

<span class="mw-page-title-main">Europium</span> Chemical element with atomic number 63 (Eu)

Europium is a chemical element; it has symbol Eu and atomic number 63. Europium is a silvery-white metal of the lanthanide series that reacts readily with air to form a dark oxide coating. It is the most chemically reactive, least dense, and softest of the lanthanide elements. It is soft enough to be cut with a knife. Europium was isolated in 1901 and named after the continent of Europe. Europium usually assumes the oxidation state +3, like other members of the lanthanide series, but compounds having oxidation state +2 are also common. All europium compounds with oxidation state +2 are slightly reducing. Europium has no significant biological role and is relatively non-toxic compared to other heavy metals. Most applications of europium exploit the phosphorescence of europium compounds. Europium is one of the rarest of the rare-earth elements on Earth.

<span class="mw-page-title-main">Indium</span> Chemical element with atomic number 49 (In)

Indium is a chemical element; it has symbol In and atomic number 49. It is a silvery-white post-transition metal and one of the softest elements. Chemically, indium is similar to gallium and thallium, and its properties are largely intermediate between the two. It was discovered in 1863 by Ferdinand Reich and Hieronymous Theodor Richter by spectroscopic methods and named for the indigo blue line in its spectrum.

<span class="mw-page-title-main">Lanthanum</span> Chemical element with atomic number 57 (La)

Lanthanum is a chemical element; it has symbol La and atomic number 57. It is a soft, ductile, silvery-white metal that tarnishes slowly when exposed to air. It is the eponym of the lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table, of which lanthanum is the first and the prototype. Lanthanum is traditionally counted among the rare earth elements. Like most other rare earth elements, its usual oxidation state is +3, although some compounds are known with an oxidation state of +2. Lanthanum has no biological role in humans but is essential to some bacteria. It is not particularly toxic to humans but does show some antimicrobial activity.

<span class="mw-page-title-main">Rubidium</span> Chemical element with atomic number 37 (Rb)

Rubidium is a chemical element; it has symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years – more than three times as long as the estimated age of the universe.

<span class="mw-page-title-main">Radium</span> Chemical element with atomic number 88 (Ra)

Radium is a chemical element; it has symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is silvery-white, but it readily reacts with nitrogen (rather than oxygen) upon exposure to air, forming a black surface layer of radium nitride (Ra3N2). All isotopes of radium are radioactive, the most stable isotope being radium-226 with a half-life of 1,600 years. When radium decays, it emits ionizing radiation as a by-product, which can excite fluorescent chemicals and cause radioluminescence. For this property, it was widely used in self-luminous paints following its discovery. Of the radioactive elements that occur in quantity, radium is considered particularly toxic, and it is carcinogenic due to the radioactivity of both it and its immediate decay product radon as well as its tendency to accumulate in the bones.

<span class="mw-page-title-main">Samarium</span> Chemical element with atomic number 62 (Sm)

Samarium is a chemical element; it has symbol Sm and atomic number 62. It is a moderately hard silvery metal that slowly oxidizes in air. Being a typical member of the lanthanide series, samarium usually has the oxidation state +3. Compounds of samarium(II) are also known, most notably the monoxide SmO, monochalcogenides SmS, SmSe and SmTe, as well as samarium(II) iodide.

<span class="mw-page-title-main">Terbium</span> Chemical element with atomic number 65 (Tb)

Terbium is a chemical element; it has the symbol Tb and atomic number 65. It is a silvery-white, rare earth metal that is malleable and ductile. The ninth member of the lanthanide series, terbium is a fairly electropositive metal that reacts with water, evolving hydrogen gas. Terbium is never found in nature as a free element, but it is contained in many minerals, including cerite, gadolinite, monazite, xenotime and euxenite.

The rubidium–strontium dating method (Rb–Sr) is a radiometric dating technique, used by scientists to determine the age of rocks and minerals from their content of specific isotopes of rubidium (87Rb) and strontium. One of the two naturally occurring isotopes of rubidium, 87Rb, decays to 87Sr with a half-life of 49.23 billion years. The radiogenic daughter, 87Sr, produced in this decay process is the only one of the four naturally occurring strontium isotopes that was not produced exclusively by stellar nucleosynthesis predating the formation of the Solar System. Over time, decay of 87Rb increases the amount of radiogenic 87Sr while the amount of other Sr isotopes remains unchanged.

<span class="mw-page-title-main">Alkaline earth metal</span> Group of chemical elements

The alkaline earth metals are six chemical elements in group 2 of the periodic table. They are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). The elements have very similar properties: they are all shiny, silvery-white, somewhat reactive metals at standard temperature and pressure.

<span class="mw-page-title-main">Celestine (mineral)</span> Sulfate mineral

Celestine (the IMA-accepted name) or celestite is a mineral consisting of strontium sulfate (SrSO4). The mineral is named for its occasional delicate blue color. Celestine and the carbonate mineral strontianite are the principal sources of the element strontium, commonly used in fireworks and in various metal alloys.

<span class="mw-page-title-main">Strontianite</span> Rare carbonate mineral and raw material for the extraction of strontium

Strontianite (SrCO3) is an important raw material for the extraction of strontium. It is a rare carbonate mineral and one of only a few strontium minerals. It is a member of the aragonite group.

The alkaline earth metal strontium (38Sr) has four stable, naturally occurring isotopes: 84Sr (0.56%), 86Sr (9.86%), 87Sr (7.0%) and 88Sr (82.58%). Its standard atomic weight is 87.62(1).

Rubidium (37Rb) has 36 isotopes, with naturally occurring rubidium being composed of just two isotopes; 85Rb (72.2%) and the radioactive 87Rb (27.8%).

<span class="mw-page-title-main">Strontium-90</span> Radioactive isotope of strontium

Strontium-90 is a radioactive isotope of strontium produced by nuclear fission, with a half-life of 28.8 years. It undergoes β− decay into yttrium-90, with a decay energy of 0.546 MeV. Strontium-90 has applications in medicine and industry and is an isotope of concern in fallout from nuclear weapons, nuclear weapons testing, and nuclear accidents.

<span class="mw-page-title-main">Strontium carbonate</span> Chemical compound

Strontium carbonate (SrCO3) is the carbonate salt of strontium that has the appearance of a white or grey powder. It occurs in nature as the mineral strontianite.

<span class="mw-page-title-main">Yttrium</span> Chemical element with atomic number 39 (Y)

Yttrium is a chemical element; it has symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and has often been classified as a "rare-earth element". Yttrium is almost always found in combination with lanthanide elements in rare-earth minerals and is never found in nature as a free element. 89Y is the only stable isotope and the only isotope found in the Earth's crust.

<span class="mw-page-title-main">Cerium</span> Chemical element with atomic number 58 (Ce)

Cerium is a chemical element; it has symbol Ce and atomic number 58. It is a soft, ductile, and silvery-white metal that tarnishes when exposed to air. Cerium is the second element in the lanthanide series, and while it often shows the oxidation state of +3 characteristic of the series, it also has a stable +4 state that does not oxidize water. It is considered one of the rare-earth elements. Cerium has no known biological role in humans but is not particularly toxic, except with intense or continued exposure.

The strontian process is an obsolete chemical method to recover sugar from molasses. Its use in Europe peaked in the middle of the 19th century. The name strontian comes from the Scottish village Strontian where the source mineral strontianite was first found.

References

  1. ↑ Greenwood and Earnshaw, p. 112
  2. ↑ "Standard Atomic Weights: Strontium". CIAAW. 1969.
  3. ↑ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (4 May 2022). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN   1365-3075.
  4. ↑ "Periodic Table of Elements: Strontium - Sr (EnvironmentalChemistry.com)". environmentalchemistry.com. Retrieved 7 December 2022.
  5. 1 2 3 Arblaster, John W. (2018). Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International. ISBN   978-1-62708-155-9.
  6. ↑ Colarusso, P.; Guo, B.; Zhang, K.-Q.; Bernath, P. F. (1996). "High-Resolution Infrared Emission Spectrum of Strontium Monofluoride" (PDF). J. Molecular Spectroscopy. 175 (1): 158. Bibcode:1996JMoSp.175..158C. doi:10.1006/jmsp.1996.0019.
  7. ↑ Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN   0-8493-0464-4.
  8. ↑ Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
  9. 1 2 "Mineral Resource of the Month: Strontium". U.S. Geological Survey. 8 December 2014. Retrieved 16 August 2015.
  10. 1 2 Greenwood and Earnshaw, pp. 112–13
  11. 1 2 3 4 5 6 C. R. Hammond The elements (pp. 4–35) in Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN   0-8493-0486-5.
  12. 1 2 3 Greenwood and Earnshaw, p. 111
  13. ↑ Greenwood and Earnshaw, p. 119
  14. ↑ Greenwood and Earnshaw, p. 121
  15. ↑ Greenwood and Earnshaw, p. 117
  16. ↑ Greenwood and Earnshaw, p. 115
  17. ↑ Greenwood and Earnshaw, p. 124
  18. ↑ Miyoshi, N.; Kamiura, K.; Oka, H.; Kita, A.; Kuwata, R.; Ikehara, D.; Wada, M. (2004). "The Barbier-Type Alkylation of Aldehydes with Alkyl Halides in the Presence of Metallic Strontium". Bulletin of the Chemical Society of Japan. 77 (2): 341. doi:10.1246/bcsj.77.341.
  19. ↑ Miyoshi, N.; Ikehara, D.; Kohno, T.; Matsui, A.; Wada, M. (2005). "The Chemistry of Alkylstrontium Halide Analogues: Barbier-type Alkylation of Imines with Alkyl Halides". Chemistry Letters. 34 (6): 760. doi:10.1246/cl.2005.760.
  20. ↑ Miyoshi, N.; Matsuo, T.; Wada, M. (2005). "The Chemistry of Alkylstrontium Halide Analogues, Part 2: Barbier-Type Dialkylation of Esters with Alkyl Halides". European Journal of Organic Chemistry. 2005 (20): 4253. doi:10.1002/ejoc.200500484.
  21. ↑ Greenwood and Earnshaw, pp. 136–37
  22. ↑ Greenwood and Earnshaw, p. 19
  23. ↑ Halperin, Edward C.; Perez, Carlos A.; Brady, Luther W. (2008). Perez and Brady's principles and practice of radiation oncology. Lippincott Williams & Wilkins. pp. 1997–. ISBN   978-0-7817-6369-1 . Retrieved 19 July 2011.
  24. 1 2 Bauman, Glenn; Charette, Manya; Reid, Robert; Sathya, Jinka (2005). "Radiopharmaceuticals for the palliation of painful bone metastases – a systematic review". Radiotherapy and Oncology. 75 (3): 258.E1–258.E13. doi:10.1016/j.radonc.2005.03.003. PMID   16299924.
  25. ↑ "Strontium | Radiation Protection | US EPA". EPA. 24 April 2012. Retrieved 18 June 2012.
  26. ↑ "Chernobyl: Assessment of Radiological and Health Impact, 2002 update; Chapter I – The site and accident sequence" (PDF). OECD-NEA. 2002. Retrieved 3 June 2015.
  27. ↑ Murray, W. H. (1977). The Companion Guide to the West Highlands of Scotland . London: Collins. ISBN   978-0-00-211135-5.
  28. ↑ Crawford, Adair (1790). "On the medicinal properties of the muriated barytes". Medical Communications. 2: 301–59.
  29. ↑ Sulzer, Friedrich Gabriel; Blumenbach, Johann Friedrich (1791). "Über den Strontianit, ein Schottisches Foßil, das ebenfalls eine neue Grunderde zu enthalten scheint". Bergmännisches Journal: 433–36.
  30. ↑ "Thomas Charles Hope, MD, FRSE, FRS (1766-1844) - School of Chemistry". www.chem.ed.ac.uk. 16 February 2024.
  31. ↑ Doyle, W.P. "Thomas Charles Hope, MD, FRSE, FRS (1766–1844)". The University of Edinburgh. Archived from the original on 2 June 2013.
  32. ↑ Although Thomas C. Hope had investigated strontium ores since 1791, his research was published in: Hope, Thomas Charles (1798). "Account of a mineral from Strontian and of a particular species of earth which it contains". Transactions of the Royal Society of Edinburgh. 4 (2): 3–39. doi:10.1017/S0080456800030726. S2CID   251579302.
  33. ↑ Murray, T. (1993). "Elementary Scots: The Discovery of Strontium". Scottish Medical Journal. 38 (6): 188–89. doi:10.1177/003693309303800611. PMID   8146640. S2CID   20396691.
  34. ↑ Hope, Thomas Charles (1794). "Account of a mineral from Strontian and of a particular species of earth which it contains". Transactions of the Royal Society of Edinburgh. 3 (2): 141–49. doi:10.1017/S0080456800020275. S2CID   251579281.
  35. ↑ Davy, H. (1808). "Electro-chemical researches on the decomposition of the earths; with observations on the metals obtained from the alkaline earths, and on the amalgam procured from ammonia". Philosophical Transactions of the Royal Society of London. 98: 333–70. Bibcode:1808RSPT...98..333D. doi:10.1098/rstl.1808.0023. S2CID   96364168.
  36. ↑ Taylor, Stuart (19 June 2008). "Strontian gets set for anniversary". Lochaber News. Archived from the original on 13 January 2009.{{cite web}}: CS1 maint: bot: original URL status unknown (link)
  37. ↑ Weeks, Mary Elvira (1932). "The discovery of the elements: X. The alkaline earth metals and magnesium and cadmium". Journal of Chemical Education. 9 (6): 1046–57. Bibcode:1932JChEd...9.1046W. doi:10.1021/ed009p1046.
  38. ↑ Partington, J. R. (1942). "The early history of strontium". Annals of Science. 5 (2): 157. doi:10.1080/00033794200201411.
  39. ↑ Partington, J. R. (1951). "The early history of strontium. Part II". Annals of Science. 7: 95. doi:10.1080/00033795100202211.
  40. ↑ Many other early investigators examined strontium ore, among them: (1) Martin Heinrich Klaproth, "Chemische Versuche über die Strontianerde" (Chemical experiments on strontian ore), Crell's Annalen (September 1793) no. ii, pp. 189–202 ; and "Nachtrag zu den Versuchen über die Strontianerde" (Addition to the Experiments on Strontian Ore), Crell's Annalen (February 1794) no. i, p. 99 ; also (2)Kirwan, Richard (1794). "Experiments on a new earth found near Stronthian in Scotland". The Transactions of the Royal Irish Academy. 5: 243–56.
  41. ↑ Fachgruppe Geschichte Der Chemie, Gesellschaft Deutscher Chemiker (2005). Metalle in der Elektrochemie. pp. 158–62.
  42. ↑ Heriot, T. H. P (2008). "strontium saccharate process". Manufacture of Sugar from the Cane and Beet. Read Books. ISBN   978-1-4437-2504-0.
  43. ↑ Börnchen, Martin. "Der Strontianitbergbau im Münsterland". Archived from the original on 11 December 2014. Retrieved 9 November 2010.
  44. ↑ Martin, Josèm; Ortega-Huertas, Miguel; Torres-Ruiz, Jose (1984). "Genesis and evolution of strontium deposits of the granada basin (Southeastern Spain): Evidence of diagenetic replacement of a stromatolite belt". Sedimentary Geology. 39 (3–4): 281. Bibcode:1984SedG...39..281M. doi:10.1016/0037-0738(84)90055-1.
  45. ↑ "Chain Fission Yields". iaea.org.
  46. ↑ Nordin, B. E. (1968). "Strontium Comes of Age". British Medical Journal. 1 (5591): 566. doi:10.1136/bmj.1.5591.566. PMC   1985251 .
  47. ↑ Turekian, K. K.; Wedepohl, K. H. (1961). "Distribution of the elements in some major units of the Earth's crust". Geological Society of America Bulletin. 72 (2): 175–92. Bibcode:1961GSAB...72..175T. doi: 10.1130/0016-7606(1961)72[175:DOTEIS]2.0.CO;2 .
  48. 1 2 Ober, Joyce A. "Mineral Commodity Summaries 2010: Strontium" (PDF). United States Geological Survey. Retrieved 14 May 2010.
  49. ↑ Heuel-Fabianek, B. (2014). "Partition Coefficients (Kd) for the Modelling of Transport Processes of Radionuclides in Groundwater" (PDF). Berichte des Forschungszentrums Jülich. 4375. ISSN   0944-2952.
  50. ↑ Stringfield, V. T. (1966). "Strontium". Artesian water in Tertiary limestone in the southeastern States. Geological Survey Professional Paper. United States Government Printing Office. pp. 138–39.
  51. ↑ Angino, Ernest E.; Billings, Gale K.; Andersen, Neil (1966). "Observed variations in the strontium concentration of sea water". Chemical Geology. 1: 145. Bibcode:1966ChGeo...1..145A. doi:10.1016/0009-2541(66)90013-1.
  52. ↑ Sun, Y.; Sun, M.; Lee, T.; Nie, B. (2005). "Influence of seawater Sr content on coral Sr/Ca and Sr thermometry". Coral Reefs. 24: 23. doi:10.1007/s00338-004-0467-x. S2CID   31543482.
  53. ↑ Kogel, Jessica Elzea; Trivedi, Nikhil C.; Barker, James M. (5 March 2006). Industrial Minerals & Rocks: Commodities, Markets, and Uses. ISBN   978-0-87335-233-8.
  54. 1 2 Mineral commodity summaries 2024 (Report). Mineral Commodity Summaries. Reston, VA: U.S. Geological Survey. January 2024. doi:10.3133/mcs2024. ISBN   978-1-4113-4544-7.
  55. ↑ Kemal, Mevlüt; Arslan, V.; Akar, A.; Canbazoglu, M. (1996). Production of SrCO3 by black ash process: Determination of reductive roasting parameters. CRC Press. p. 401. ISBN   978-90-5410-829-0.
  56. 1 2 3 4 MacMillan, J. Paul; Park, Jai Won; Gerstenberg, Rolf; Wagner, Heinz; Köhler, Karl and Wallbrecht, Peter (2002) "Strontium and Strontium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim. doi : 10.1002/14356007.a25_321.
  57. ↑ "Cathode Ray Tube Glass-To-Glass Recycling" (PDF). ICF Incorporated, USEP Agency. Archived from the original (PDF) on 19 December 2008. Retrieved 7 January 2012.
  58. ↑ Ober, Joyce A.; Polyak, Désirée E. "Mineral Yearbook 2007: Strontium" (PDF). United States Geological Survey. Retrieved 14 October 2008.
  59. ↑ Méar, F.; Yot, P.; Cambon, M.; Ribes, M. (2006). "The characterization of waste cathode-ray tube glass". Waste Management. 26 (12): 1468–76. Bibcode:2006WaMan..26.1468M. doi:10.1016/j.wasman.2005.11.017. PMID   16427267.
  60. ↑ Price, T. Douglas; Schoeninger, Margaret J.; Armelagos, George J. (1985). "Bone chemistry and past behavior: an overview". Journal of Human Evolution. 14 (5): 419–47. Bibcode:1985JHumE..14..419P. doi:10.1016/S0047-2484(85)80022-1.
  61. ↑ Steadman, Luville T.; Brudevold, Finn; Smith, Frank A. (1958). "Distribution of strontium in teeth from different geographic areas". The Journal of the American Dental Association. 57 (3): 340–44. doi:10.14219/jada.archive.1958.0161. PMID   13575071.
  62. ↑ Schweissing, Matthew Mike; Grupe, Gisela (2003). "Stable strontium isotopes in human teeth and bone: a key to migration events of the late Roman period in Bavaria". Journal of Archaeological Science. 30 (11): 1373–83. Bibcode:2003JArSc..30.1373S. doi:10.1016/S0305-4403(03)00025-6.
  63. ↑ Dasch, J. (1969). "Strontium isotopes in weathering profiles, deep-sea sediments, and sedimentary rocks". Geochimica et Cosmochimica Acta. 33 (12): 1521–52. Bibcode:1969GeCoA..33.1521D. doi:10.1016/0016-7037(69)90153-7.
  64. 1 2 Krom, M. D.; Cliff, R.; Eijsink, L. M.; Herut, B.; Chester, R. (1999). "The characterisation of Saharan dusts and Nile particulate matter in surface sediments from the Levantine basin using Sr isotopes". Marine Geology. 155 (3–4): 319–30. Bibcode:1999MGeol.155..319K. doi:10.1016/S0025-3227(98)00130-3.
  65. ↑ Benson, L.; Cordell, L.; Vincent, K.; Taylor, H.; Stein, J.; Farmer, G. & Kiyoto, F. (2003). "Ancient maize from Chacoan great houses: where was it grown?". Proceedings of the National Academy of Sciences. 100 (22): 13111–15. Bibcode:2003PNAS..10013111B. doi: 10.1073/pnas.2135068100 . PMC   240753 . PMID   14563925.
  66. ↑ English NB; Betancourt JL; Dean JS; Quade J. (October 2001). "Strontium isotopes reveal distant sources of architectural timber in Chaco Canyon, New Mexico". Proc Natl Acad Sci USA. 98 (21): 11891–96. Bibcode:2001PNAS...9811891E. doi: 10.1073/pnas.211305498 . PMC   59738 . PMID   11572943.
  67. ↑ Barnett-Johnson, Rachel; Grimes, Churchill B.; Royer, Chantell F.; Donohoe, Christopher J. (2007). "Identifying the contribution of wild and hatchery Chinook salmon (Oncorhynchus tshawytscha) to the ocean fishery using otolith microstructure as natural tags". Canadian Journal of Fisheries and Aquatic Sciences. 64 (12): 1683–92. Bibcode:2007CJFAS..64.1683B. doi:10.1139/F07-129. S2CID   54885632.
  68. ↑ Porder, S.; Paytan, A. & E.A. Hadly (2003). "Mapping the origin of faunal assemblages using strontium isotopes". Paleobiology. 29 (2): 197–204. doi:10.1666/0094-8373(2003)029<0197:MTOOFA>2.0.CO;2. S2CID   44206756.
  69. ↑ Van der Heggen, David (October 2022). "Persistent Luminescence in Strontium Aluminate: A Roadmap to a Brighter Future". Advanced Functional Materials. 32 (52). doi:10.1002/adfm.202208809. hdl: 1854/LU-01GJ1338HX6QQBT438E4QW442N . S2CID   253347258 . Retrieved 21 April 2023.
  70. ↑ "Chemistry of Firework Colors – How Fireworks Are Colored". Chemistry.about.com. 10 April 2012. Archived from the original on 13 May 2008. Retrieved 14 April 2012.
  71. ↑ "Ferrite Permanent Magnets". Arnold Magnetic Technologies. Archived from the original on 14 May 2012. Retrieved 18 January 2014.
  72. ↑ "Barium Carbonate". Chemical Products Corporation. Archived from the original on 6 October 2014. Retrieved 18 January 2014.
  73. ↑ Ghom (1 December 2005). Textbook of Oral Medicine. Jaypee Brothers, Medical Publishers. p. 885. ISBN   978-81-8061-431-6.[ permanent dead link ]
  74. ↑ Cartlidge, Edwin (28 February 2018). "With better atomic clocks, scientists prepare to redefine the second". Science | AAAS. Retrieved 10 February 2019.
  75. ↑ "Recommended values of standard frequencies - BIPM". www.bipm.org. Retrieved 21 May 2023.
  76. ↑ "FDA ANDA Generic Drug Approvals". Food and Drug Administration.
  77. ↑ "What are the fuels for radioisotope thermoelectric generators?". qrg.northwestern.edu.
  78. ↑ Doyle, James (30 June 2008). Nuclear safeguards, security and nonproliferation: achieving security with technology and policy. Elsevier. p. 459. ISBN   978-0-7506-8673-0.
  79. ↑ O'Brien, R. C.; Ambrosi, R. M.; Bannister, N. P.; Howe, S. D.; Atkinson, H. V. (2008). "Safe radioisotope thermoelectric generators and heat sources for space applications". Journal of Nuclear Materials. 377 (3): 506–21. Bibcode:2008JNuM..377..506O. doi:10.1016/j.jnucmat.2008.04.009.
  80. ↑ "Strontium 343730". Sigma-Aldrich.
  81. ↑ De Deckker, Patrick (2004). "On the celestite-secreting Acantharia and their effect on seawater strontium to calcium ratios". Hydrobiologia. 517 (1–3): 1. Bibcode:2004HyBio.517....1D. doi:10.1023/B:HYDR.0000027333.02017.50. S2CID   42526332.
  82. ↑ Pors Nielsen, S. (2004). "The biological role of strontium". Bone. 35 (3): 583–88. doi:10.1016/j.bone.2004.04.026. PMID   15336592.
  83. ↑ Cabrera, Walter E.; Schrooten, Iris; De Broe, Marc E.; d'Haese, Patrick C. (1999). "Strontium and Bone". Journal of Bone and Mineral Research. 14 (5): 661–68. doi: 10.1359/jbmr.1999.14.5.661 . PMID   10320513. S2CID   32627349.
  84. ↑ Emsley, John (2011). Nature's building blocks: an A–Z guide to the elements. Oxford University Press. p. 507. ISBN   978-0-19-960563-7.
  85. ↑ Agency for Toxic Substances and Disease Registry (26 March 2014). "Strontium | Public Health Statement | ATSDR". cdc.gov. Agency for Toxic Substances and Disease Registry. Retrieved 12 January 2024.
  86. ↑ Tiller, B. L. (2001), "4.5 Fish and Wildlife Surveillance" (PDF), Hanford Site 2001 Environmental Report, DOE, archived from the original (PDF) on 11 May 2013, retrieved 14 January 2014
  87. ↑ Driver, C. J. (1994), Ecotoxicity Literature Review of Selected Hanford Site Contaminants (PDF), DOE, doi:10.2172/10136486, OSTI   10136486 , retrieved 14 January 2014
  88. ↑ "Freshwater Ecology and Human Influence". Area IV Envirothon. Archived from the original on 1 January 2014. Retrieved 14 January 2014.
  89. ↑ "Radioisotopes That May Impact Food Resources" (PDF). Epidemiology, Health and Social Services, State of Alaska. Archived from the original on 21 August 2014. Retrieved 14 January 2014.{{cite web}}: CS1 maint: bot: original URL status unknown (link)
  90. ↑ "Human Health Fact Sheet: Strontium" (PDF). Argonne National Laboratory. October 2001. Archived from the original (PDF) on 24 January 2014. Retrieved 14 January 2014.
  91. ↑ "Biological Half-life". HyperPhysics. Retrieved 14 January 2014.
  92. ↑ Glasstone, Samuel; Dolan, Philip J. (1977). "XII: Biological Effects" (PDF). The effects of Nuclear Weapons. p. 605. Retrieved 14 January 2014.
  93. ↑ Shagina, N. B.; Bougrov, N. G.; Degteva, M. O.; Kozheurov, V. P.; Tolstykh, E. I. (2006). "An application of in vivo whole body counting technique for studying strontium metabolism and internal dose reconstruction for the Techa River population". Journal of Physics: Conference Series. 41 (1): 433–40. Bibcode:2006JPhCS..41..433S. doi: 10.1088/1742-6596/41/1/048 . S2CID   32732782.
  94. ↑ Meunier P. J.; Roux C.; Seeman E.; Ortolani, S.; Badurski, J. E.; Spector, T. D.; Cannata, J.; Balogh, A.; Lemmel, E. M.; Pors-Nielsen, S.; Rizzoli, R.; Genant, H. K.; Reginster, J. Y. (January 2004). "The effects of strontium ranelate on the risk of vertebral fracture in women with postmenopausal osteoporosis" (PDF). New England Journal of Medicine. 350 (5): 459–68. doi:10.1056/NEJMoa022436. hdl:2268/7937. PMID   14749454.
  95. ↑ Reginster JY; Seeman E; De Vernejoul MC; Adami, S.; Compston, J.; Phenekos, C.; Devogelaer, J. P.; Diaz Curiel, M.; Sawicki, A.; Goemaere, S.; Sorensen, O. H.; Felsenberg, D.; Meunier, P. J. (May 2005). "Strontium ranelate reduces the risk of nonvertebral fractures in postmenopausal women with osteoporosis: treatment of peripheral osteoporosis (TROPOS) study" (PDF). The Journal of Clinical Endocrinology & Metabolism. 90 (5): 2816–22. doi: 10.1210/jc.2004-1774 . PMID   15728210.
  96. ↑ "Strontium ranelate: cardiovascular risk – restricted indication and new monitoring requirements". Medicines and Healthcare products Regulatory Agency, UK. March 2014.
  97. ↑ Price, Charles T.; Langford, Joshua R.; Liporace, Frank A. (5 April 2012). "Essential Nutrients for Bone Health and a Review of their Availability in the Average North American Diet". Open Orthop. J. 6: 143–49. doi:10.2174/1874325001206010143. PMC   3330619 . PMID   22523525.
  98. 1 2 "Strontium". WebMD . Retrieved 20 November 2017.
  99. 1 2 "Strontium for Osteoporosis". WebMD . Retrieved 20 November 2017.
  100. ↑ Hahn, G.S. (1999). "Strontium Is a Potent and Selective Inhibitor of Sensory Irritation" (PDF). Dermatologic Surgery. 25 (9): 689–94. doi:10.1046/j.1524-4725.1999.99099.x. PMID   10491058. Archived from the original (PDF) on 31 May 2016.
  101. ↑ Hahn, G.S. (2001). "Anti-irritants for Sensory Irritation". Handbook of Cosmetic Science and Technology. CRC Press. p. 285. ISBN   978-0-8247-0292-2.
  102. ↑ Kim, Hyun Jeong; Kim, Min Jung; Jeong, Se Kyoo (2006). "The Effects of Strontium Ions on Epidermal Permeability Barrier". The Korean Dermatological Association, Korean Journal of Dermatology. 44 (11): 1309. Archived from the original on 4 June 2021. Retrieved 31 March 2014.
  103. 1 2 3 Potera, Carol (2011). "HAZARDOUS WASTE: Pond Algae Sequester Strontium-90". Environ Health Perspect. 119 (6): A244. doi: 10.1289/ehp.119-a244 . PMC   3114833 . PMID   21628117.
  104. ↑ Boehm, BO; Rosinger, S; Belyi, D; Dietrich, JW (18 August 2011). "The parathyroid as a target for radiation damage". The New England Journal of Medicine. 365 (7): 676–8. doi: 10.1056/NEJMc1104982 . PMID   21848480.
  105. ↑ Liu, Mingxue; Dong, Faqin; Kang, Wu; Sun, Shiyong; Wei, Hongfu; Zhang, Wei; Nie, Xiaoqin; Guo, Yuting; Huang, Ting; Liu, Yuanyuan (2014). "Biosorption of Strontium from Simulated Nuclear Wastewater by Scenedesmus spinosus under Culture Conditions: Adsorption and Bioaccumulation Processes and Models". Int J Environ Res Public Health. 11 (6): 6099–6118. doi: 10.3390/ijerph110606099 . PMC   4078568 . PMID   24919131.

Bibliography

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.