unique use of iodine is in various analytical chemistry procedures, particularly the detection of glucose polymers such as starch. iodine-impregnated polymer films are used as extremely cost-effective light polarizing optical filters found in products such as lcd screens, sunglasses, and optical microscopes...
ionizing radiation. some other properties of lanthanum are exploited in a variety of applications. many lanthanum compounds can be induced to emit electrons when treated with heat in a process called thermionic emission. lanthanum boride crystals are used as electron emission sources for electron microscopes...