Uses of Strontium

The electron radiation in a cathode-ray tube that activates the color phosphors in a TV screen also creates an X-rays. Strontium has the ability to block this X-ray emission. Because of that so much strontium carbonate is added to the melt during the manufacture of glass for the screens that the resulting content corresponds to 8-12% strontium oxide. The law requires that viewers are shielded from the X-rays in this way and this has created the major use of strontium and demand continues to increase with the increased popularity of larger screen sizes. Flat-screen technology may reduce the demand for strontium in TV appKcations. 

Another major end use for strontium is as strontium ferrite SrOjFejOjjg in permanent ceramic magnets. Because of their high coercive force, insensitivity to high temperatures and corrosion resistance they are used extensively in small motors for automobile windshield wipers and magnetically attached decorative items. 

As the compound strontium titanate SrTiOj, the element has a rather original use in imitation diamonds. It has, in fact, a higher dispersion than diamond and is thus more colorful. Its hardness is, however, much lower, 5.5 compared to 10 on Mohs scale. It is known nsfahulite in the jewelry industry. It has to a large extent been replaced by cubic zirconia CZ, which has higher hardness and better matches the dispersion of diamond. 

As strontium burns with a brilliant red flame it has been used for pyrotechnics. It is treated below (in this chapter) in section 16.5. 

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The principal use of strontium nitrate is in the manufacture of pyrotechnics (qv) as it imparts a characteristic, hrilliant crimson color to a flame. Railroad fusees and distress or rescue signaling devices are the main uses for strontium nitrate. It is also used to make red tracer bullets for the military. 

The y, -double bond of a linear dienone is selectively reduced over palladium in the presence of a trace of base.15,62,85,86,137 Presaturation of the catalyst with hydrogen enhances the selectivity in the reaction.137 In the absence of base, the use of strontium carbonate or barium sulfate as a support for the palladium is preferred.56,57 A benzene solvent is also beneficial.78... 

Despite the potential to track the spatial movement of marine shell beads, archaeometric attempts at sourcing have been minimal. We are aware of only three other groups that have taken this approach including a neutron activation analysis (NAA) of Busycon sp. shells and artifacts in the American Southeast (/), the use of strontium isotopes as a measure of geologic age of fossil shells in Southwest Europe (2), and the use of oxygen isotope ratios to source Sporufylus sp. beads in Central Europe (5). 

Raloxifene is recommended in patients (NICE, 2008) in whom bisphosphonates are contraindicated, those who cannot comply with the requirements needed to take bisphosphonates, or who have had an unsatisfactory response or are intolerant of bisphosphonates. Strontium ranelate is a suitable alternative if a bisphosphonate cannot be taken. However, NICE guidelines on secondary prevention of osteoporosis does not currently recommend the use of strontium ranelate. 

For magnetic applications, the use of strontium ferrite powder has been characterised (234). The use of barium ferrite has been optimised (362). 

Wallander, H. (2000b). Use of strontium isotopes and foliar K content to estimate weathering of biotite induced by pine seedlings colonised by ectomycorrhizal fungi from two different soils. Plant and Soil, 221, 215-29. 

Several studies have used radiogenic isotopes to study groundwater questions on relatively short (or local) length scales (<2 km). Stuckless et al. (1991) combined the use of strontium and uranium isotope measurements, in studies of groundwaters and secondary calcite deposits in fault zones at Yucca Mountain, Nevada. They tested whether veins formed by upwelling of deep-seated waters... 

Siegel D. I., Bickford M. E., and Orrell S. E. (2000) The use of strontium and lead isotopes to identify sources of water beneath the Eresh Kills Eandfill, Staten Island, New York, USA. A/)/)/. Geochem. 15, 493-500. 

Lyons W. B., Tyler S. W., Gaudette H. E., and Long D. T. (1995) The use of strontium isotopes in determining groundwater mixing and brine fingering in a playa spring zone. Lake Tyrrel, Australia. J. Hydrol. 167, 225—239. 

In addition may medication related to the uremic state lead to important trace element accumulation. In the past this has clearly been established for aluminum resulting from the use of aluminum hydroxide as a phosphate binding agent. As aluminum-based phosphate binders may be contaminated with other elements, e.g. strontium the possibility for a simultaneous accumulation of different elements has been suggested [7]. Strontium is mainly eliminated by the kidney and has been associated with bone mineralization defects when present at high concentrations. In view of this the use of strontium ranelate for the treatment and preven-... 

Strontium levels are increased in plasma of renal failure patients. In dialysis patients the accumulation of the element has been reported to be strongly centre and country-dependent and values up to 50 times those noted in subjects with normal renal function have been reported within the latter population [20]. In addition to the renal failure, accumulation of the element turned out to be due to the use of strontium-contaminated dialysis fluids secondary to the addition of contaminated acetate-based concentrates. To which other factors such as age, medication, treatment modalities etc. .. also contribute to the increased levels is not yet fully understood. 

One of the major uses of strontium has been in the production of color cathode ray tubes (CRTs) used in televisions and computer monitors. However, changes in electronics technology and the popularity of flat-panel screens (which use far less or even no strontium) have led to decreased strontium demand for this purpose in the United States and Europe. However, strontium is also used in the manufacture of ceramics and specialty glass. One of its radioactive isotopes is used in industry and medical studies. 

In the mouth, mineralization is controlled partly by proteins such as statherin from the salivary gland, which maintains a supersaturation of calcium and phosphate in the mouth. The basic mineral in tooth enamel is hydroxyapatite, in which it is possible to substitute Sr(II) for Ca(II), and F for OH isomorphously, hence the use of strontium and fluoride salts in toothpastes, said to confer extra strength to the enamel and antibacterial properties. 

The name comes from the town of Strontian in Scotland and was given to the element by Thomas Hope (1766-1844). There are many claims for the original discovery of strontium. William Cruikshank, in 1787, and Adair Crawford, in 1790, both examined strontianite (SrC03) and recognized that it had unique properties. Thomas Hope noted an unknown earth in 1791. Martin Klaproth presented a paper on a number of strontium compounds in 1793 and 1794. Richard Kirwan (1733-1812) examined a number of strontium compounds and presented his findings in 1794. It was Davy who isolated strontium metal, in 1808. Strontium does not occur in pure form in nature but is found in small quantities in many places. Some forms of strontium are radioactive, particularly 90Sr, which has been found in nuclear fallout. It can also be used in SNAP devices (Systems for Nuclear Auxiliary Power) as a power source. The main commercial use of strontium is in the glass of color television picture tubes. 

Crawford ED, Kozlowski JM, Debruyne FM, et al. The use of strontium 89 for palliation of pain from bone metastases associated with hormone-refractory prostate cancer. Urology 1994 44 481-485. 

Production, Import/Export, Use, Release, and Disposal. Data regarding the past and present production and import/export volumes for strontium are available. The uses of strontium and strontium compounds are well known. Since strontium is not covered under Superfund Amendments and Reauthorization Act (SARA), Title III, manufacturers and users are not required to report releases to the EPA s Toxic Release Inventory. The disposal of radiostrontium and radiostrontium contaminated wastes is governed by the U.S. Nuclear Regulatory Commission (NRC) regulations, and releases of radiostrontium and radiostrontium contaminated wastes are governed by NRC and EPA regulations. 

Graustein WC, Armstrong RL. 1983. The use of strontium-87/strontium-86 ratios to measure atmospheric transport into forested watersheds. Science 219 289-292. 

Mortimer D, Curtis EF, Dravland JE. 1986. The use of strontium-substituted media for capacitating human spermatozoa an improved sperm preparation method for the zona-free hamster egg penetration test. Fertil Steril 46(1) 97-103. 

Most uses of strontium and barium are fairly stable. The biggest increase in production is expected to be of strontium carbonate because it provides the color red to color televisions, the numbers of which are increasing exponentially worldwide. 

Denison RE, Hetherington EA, Bishop BA, Dahl DA, Koepnick RB (1993) The use of strontium isotopes in stratigraphic studies an example from North Carolina. Southeastern Geol 33 53-69 DePaolo DJ, Ingram BL (1985) High-resolution stratigraphy with strontium isotopes. Science 227 938-941 Dickens GR (1999) The blast in the past. Nature 401 752-753, 755... 

The two mineral sources for strontium are the sulfate (celes-tite) and carbonate (strontianite). The main use of strontium is as a component in colour television faceplate glass ( 8% SrO is incorporated into the glass) where its function is to stop X-ray emissions from the cathode ray tube (CRT). However, the increasing market for CRT-free flat-screen televisions is having a dramatic effect on the demand for strontium. Other uses of strontium include ferrite ceramic magnets and pyrotechnics (see Flame tests in Section 12.3). 

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