Isotopes: There are 20 known isotopes of strontium, 4 stable and 16 unstable. Natural strontium is a mixture of the 4 stable isotopes. Properties: Strontium is softer than calcium and decomposes more vigorously in water. Finely divided strontium metal ignites spontaneously in air. Strontium is a silvery metal, but it rapidly oxidizes to a yellowish color. Because of its propensity for oxidation and ignition, strontium is typically stored under kerosene. Strontium salts color flames crimson and are used in fireworks and flares. Uses: Strontium-90 is used in Systems for Nuclear Auxilliary Power (SNAP) devices. Strontium is used in producing glass for color television picture tubes.
In contrast, a SKU, or Stock Keeping Unit, is a number assigned to a product by the company for stock-keeping purposes and internal operations. The UPC code is affixed to a product wherever it is sold, remaining a constant throughout the productâs shelf life.
ECU. An electronic device that remotely controls home climate (e.g., heating, air conditioning), security (e.g., lighting, door locks, drapes), and communication devices (telephone, television). ECUs are often, but not exclusively, used by persons with functional limitations.