Strontium thermal properties

Cheng Z, Zha S, Aguilar L, and Liu M. Chemical, electrical, and thermal properties of strontium doped lanthanum vanadate. Solid State Ionics 2005 176 1921-1928. 

Inoue, A., Cesium- and strontium-exchange properties of thermally altered Na-montmorillonite, Clay Sci., 6, 251, 1987. 

Barium is a member of the aLkaline-earth group of elements in Group 2 (IIA) of the period table. Calcium [7440-70-2], Ca, strontium [7440-24-6], Sr, and barium form a closely aUied series in which the chemical and physical properties of the elements and thek compounds vary systematically with increa sing size, the ionic and electropositive nature being greatest for barium (see Calcium AND CALCIUM ALLOYS Calcium compounds Strontium and STRONTIUM compounds). As size increases, hydration tendencies of the crystalline salts increase solubiUties of sulfates, nitrates, chlorides, etc, decrease (except duorides) solubiUties of haUdes in ethanol decrease thermal stabiUties of carbonates, nitrates, and peroxides increase and the rates of reaction of the metals with hydrogen increase. 

The material is impact-sensitive when dry and is supplied and stored damp with ethanol. It is used as a saturated solution and it is important to prevent total evaporation, or the slow growth of large crystals which may become dried and shock-sensitive. Lead drains must not be used, to avoid formation of the detonator, lead azide. Exposure to acid conditions may generate explosive hydrazoic acid [1], It has been stated that barium azide is relatively insensitive to impact but highly sensitive to friction [2], Strontium, and particularly calcium azides show much more marked explosive properties than barium azide. The explosive properties appear to be closely associated with the method of formation of the azide [3], Factors which affect the sensitivity of the azide include surface area, solvent used and ageing. Presence of barium metal, sodium or iron ions as impurities increases the sensitivity [4], Though not an endothermic compound (AH°f —22.17 kJ/mol, 0.1 kj/g), it may thermally decompose to barium nitride, rather than to the elements, when a considerable exotherm is produced (98.74 kJ/mol, 0.45 kJ/g of azide) [5]. 

The metal-donor bonds are predominantly ionic and become more labile for calcium, strontium, and barium compared to beryllium and magnesium. The solubility and stability of the complexes decrease from calcium to barium. The 1 1 adducts of NHCs with BH3 or BF3 (28 and 29) are thermally stable and can be sublimed without decomposition. This is in sharp contrast to the properties of conventional carbenes, which rely on a pronounced metal-to-ligand back donation and are, thus, not suited to forming adducts with electron-poor fragments such as... 

Highly pure lanthanum oxide is used to make optical glass of high refractive index for camera lenses. It also is used to make glass fibers. The oxide also is used to improve thermal and electrical properties of barium and strontium titanates. Other applications are in glass polishes carbon arc electrodes fluorescent type phosphors and as a diluent for nuclear fuels. In such apph-cations, lanthinum oxide is usually combined with other rare earth oxides. 

How can the oxides, peroxides, and hydroxides of the alkaline-earth metals be prepared What are the commercial names of calcium and barium hydroxide solutions How do the solubility, basic properties, and thermal stability of the hydroxides change in the series calcium-strontium-barium ... 

In this work, erbium doped strontium barium niobate glasses have been irradiated with a femtosecond laser. The properties of these glasses and the changes induced by a cw laser have been studied in a previous paper . Optical measurements show the changes of the local structure in a localized area after the irradiation and they arc compared with the bulk glass ceramic sample obtained by thermal treatment with a furnace. 

Without the overlap of energy bands, the periodic properties of metals could not be explained. In the absence of the d- and p-bands, we would expect the s-band to be half-filled for the alkali metals (group lA) and completely filled for the alkaline-earth metals (group 2A). If that were true, metals like magnesium, calcium, and strontium would not be good electrical and thermal conductors, in disagreement with experimental observations. 

Marina OA, Canfield NL, Stevenson JW (2002) Thermal, electrical, and electrocatalytical properties of lanthanum-doped strontium titanate. Solid State Ionics 149 21... 

Because of the great potential selectivity of solids, GSC is especially desirable for the separation of isomers and high-molecular-weight compounds which are thermally stable. These properties of GSC prompted research into the use of barium and strontium halides (chloride, bromide, and iodide) as adsorbent supports for GSC (all columns were made of glass 6 ft x 0.25 in. o.d.) (23). Conclusions from this study showed the following ... 

Shao and Haile (2004) suggested a material based on strontium-doped barium cobaltite ferrite [BaFe03 Bai xSrjcCoyFei 3,03 (BSCF) (0.1 data reported by Wei et al. (2005), difficulties arise because of the complex temperature dependence of the thermal expansion coefficient. According to results obtained by Lim et al. (2(K)7), this coefficient matches that of the electrolyte when x = 0.2. 

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