Strontium-89 chloride

A variety of other metals and their complexes have been studied for radioprotective activity. Among these are copper glycinate, strontium chloride, ZnNa -diethylenetriaminepentaacetate (ZnDTPA), and selenium, which has been studied because of its relationship to endogenous antioxidant mechanisms, especiaHy GSH peroxidase and vitamin E. 

Strontium [7440-24-6] Sr, is in Group 2 (IIA) of the Periodic Table, between calcium and barium. These three elements are called alkaline-earth metals because the chemical properties of the oxides fall between the hydroxides of alkaU metals, ie, sodium and potassium, and the oxides of earth metals, ie, magnesium, aluminum, and iron. Strontium was identified in the 1790s (1). The metal was first produced in 1808 in the form of a mercury amalgam. A few grams of the metal was produced in 1860—1861 by electrolysis of strontium chloride [10476-85-4]. 

Production. MetaUic strontium was first successfully produced by the electrolysis of fused strontium chloride. Although many attempts were made to develop this process, the deposited metal has a tendency to migrate into the fused electrolyte and the method was not satisfactory. A more effective early method was that described in Reference r5. Strontium oxide is reduced thermally with aluminum according to the following reaction ... 

Strontium chloride [10476-85-4] SrCl2, is similar to calcium chloride but is less soluble in water (100.8 g in 100 mL water at 100°C). The anhydrous salt forms colorless cubic crystals with a specific gravity of 3.052 and a melting point of 873°C. Strontium chloride is used in toothpaste formulations (see... 

Dentifrices are also vehicles for agents that alleviate dentinal hypersensitivity. Among the materials that have given positive results in clinical tests are potassium nitrate [7757-79-1] (5%) and strontium chloride [10476-85-4] (10%). 

Aqueous hydrofluoric acid can be freed from lead by adding ImL of 10% strontium chloride per KXhnL of acid, lead being co-precipitated as lead fluoride with the strontium fluoride. If the hydrofluoric acid is decanted from the precipitate and the process repeated, the final lead content in the acid is less than 0.003 ppm. Similarly, lead can be precipitated from a nearly saturated sodium carbonate solution by adding 10% strontium chloride dropwise (l-2mL per lOOmL) followed by filtration. (If the sodium carbonate is required as a solid, the solution can be evaporated to dryness in a platinum dish.) Removal of lead from potassium chloride uses precipitation as lead sulfide by bubbling H2S, followed, after filtration, by evaporation and recrystallisation of the potassium chloride. 

Strontium chloride (6H2O) [1025-70-4] M 266.6, m 61 (rapid heating), 114-lS0 (loses 5H2O), 868 (anhydr). Crystd from warm water (0.5mL/g) by cooling to 0°. 

Chlor-siure, /. chloric acid. -sMureanhydrid, n. chloric anhydride, chlorine(V) oxide, -schwefel, n. sulfur chloride (esp. the monochloride). -silber, n. silver chloride, -sili-cium, n. silicon tetrachloride, -soda, /. = Chlornatron. -stickstoff, m. nitrogen chloride. -Strom, m. stream of chlorine, -strontium, n. strontium chloride, -suifonsaure, /. chlorosulfonic acid, chlorosulfuric acid, -toluol, n. chlorotoluene. -fibertrager, m. chlorine carrier. 

The determination of magnesium in potable water is very straightforward very few interferences are encountered when using an acetylene-air flame. The determination of calcium is however more complicated many chemical interferences are encountered in the acetylene-air flame and the use of releasing agents such as strontium chloride, lanthanum chloride, or EDTA is necessary. Using the hotter acetylene-nitrous oxide flame the only significant interference arises from the ionisation of calcium, and under these conditions an ionisation buffer such as potassium chloride is added to the test solutions. 

Preparation of the standard solutions. For procedure (i) it is necessary to incorporate a releasing agent in the standard solutions. Three different releasing agents may be used for calcium, (a) lanthanum chloride, (b) strontium chloride and (c) EDTA of these (a) is the preferred reagent, but (b) or (c) make satisfactory alternatives. 

In this discussion, two mutually canceling simplifications have been made. For the transition value of the radius ratio the phenomenon of double repulsion causes the inter-atomic distances in fluorite type crystals to be increased somewhat, so that R is equal to /3Rx-5, where i has a value of about 1.05 (found experimentally in strontium chloride). Double repulsion is not operative in rutile type crystals, for which R = i M + Rx- From these equations the transition ratio is found to be (4.80/5.04)- /3i — 1 = 0.73, for t = 1.05 that is, it is increased 12%. But Ru and Rx in these equations are not the crystal radii, which we have used above, but are the univalent crystal radii multiplied by the constant of Equation 13 with z placed equal to /2, for M++X2. Hence the univalent crystal radius ratio should be used instead of the crystal radius ratio, which is about 17% smaller (for strontium chloride). Because of its simpler nature the treatment in the text has been presented it is to be emphasized that the complete agreement with the theoretical transition ratio found in Table XVII is possibly to some extent accidental, for perturbing influences might cause the transition to occur for values a few per cent, higher or lower. 

In lithium chloride, bromide and iodide, magnesium sulfide and selenide and strontium chloride the inter-atomic distances depend on the anion radius alone, for the anions are in mutual contact the observed anion-anion distances agree satisfactorily with the calculated radii. In lithium fluoride, sodium chloride, bromide and iodide and magnesium oxide the observed anion-cation distances are larger than those calculated because of double repulsion the anions are approaching mutual contact, and the repulsive forces between them as well as those between anion and cation are operative. 

Given the strontium chloride crystal, write the defect reaction(s) expected if lithium chloride is present as an impurity. Do likewise for the antimony chloride impurity. Also, write the defeet reactions expected if both impurities are present in equal quantities. 

C6H1206 Sr 2+ Cl2 5 HjO epi-Inositol strontium chloride, pentahydrate EPINSR 38 432... 

There are a number of interferences that can occur in atomic absorption and other flame spectroscopic methods. Anything that decreases the number of neutral atoms in the flame will decrease the absorption signal. Chemical interference is the most commonly encountered example of depression of the absorption signal. Here, the element of interest reacts with an anion in solution or with a gas in the flame to produce a stable compound in the flame. For example, calcium, in the presence of phosphate, will form the stable pyrophosphate molecule. Refractory elements will combine with 0 or OH radicals in the flame to produce stable monoxides and hydroxides. Fortunately, most of these chemical interferences can be avoided by adding an appropriate reagent or by using a hotter flame. The phosphate interferences, for example, can be eliminated by adding 1 % strontium chloride or lanthanum chloride to the solution. The strontium or lanthanum preferentially combines with the phosphate to prevent its reaction with the calcium. Or, EDTA can be added to complex the calcium and prevent its combination with the phosphate. 

Strontium chloride is added to a solution of sodium sulfate ... 

Strontium chloride, 23 318, 323 Strontium chromate, 23 323, 6 557t, 558 air standards and classification, 6 549t molecular formula, properties, and uses, 6 562t... 

C6Hi208 SrCl2-5 H20 epi-Inositol strontium chloride, pentahy-drate (EPINSR)39... 

Other inorganic crystals studied by Mark and his collaborators, sometimes leading to complete structure determinations, include strontium chloride, zinc hydroxide, tin tetraiodide, potassium chlorate, potassium permanganage, and ammonium ferrocyanide. Minerals investigated by them include CaSO (anhydrite), BaSO (barite), PbSO, Fe2TiO[j (pseudobrookite), and three forms of Al2Si05 (cyanite, andalusite, and sillimanite). 

Materials Bunsen burner cotton swabs (6) distilled water crystals of lithium chloride, sodium chloride, potassium chloride, calcium chloride, strontium chloride, unknown... 

Strontium metal is not found in its elemental state in nature. Its salts and oxide compounds constitute only 0.025% of the Earths crust. Strontium is found in Mexico and Spain in the mineral ores of strontianite (SrCO ) and celestite (SrSO ). As these ores are treated with hydrochloric acid (HCl), they produce strontium chloride (SrCy that is then used, along with potassium chloride (KCl), to form a eutectic mixture to reduce the melting point of the SrCl, as a molten electrolyte in a graphite dish-shaped electrolysis apparatus. This process produces Sr cations collected at the cathode, where they acquire electrons to form strontium metal. At the same time, Cl anions give up electrons at the anode and are released as chlorine gas Cl T. 

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