Zeta potential is the energy required to shear the particle as well as its internal layer of counter-ions away from the external layer/bulk medium. It is measured in millivolts.
Mullite is the mineralogical name for the only chemically stable intermediate phase in the SiO2–Al2O3 system.
Nickel/chromium alloys have excellent oxidation resistance, wear-resistance and high-temperature properties. Typical applications include heating elements and thermocouples.
Iron (Fe) is a metal that has been known since ancient times. In fact, the Earth’s crust is made up of 5% of iron, which is the second most abundant metal after aluminum.
Black was the first person to recognize magnesium (Mg) as an element in 1755. Later, in 1808, Davy isolated this element by evaporating mercury from a magnesium amalgam.
Tin (Sn) is mostly found in cassiterite (SnO2) and has been known since ancient times. It is obtained by reducing the ore with coal in a reverberatory furnace.
Although lead occurs as such in nature, it is rare. Lead is chiefly obtained from galena (PbS) through the process of roasting.
By Reginald Davey
28 Jul 2001
Ancient Chinese and Hindus were familiar with mercury (Hg). The metal was also found in Egyptian tombs of 1500 BC. Mercury rarely occurs as such in nature.
Metallic zinc was produced in India by reducing calamine with organic substances like wool, in the 13th century A.D. Marggraf rediscovered zinc in 1746 and showed that metallic zinc could also be synthesized by reducing calamine with charcoal.
Platinum (Pt) was discovered by Ulloa in 1735 and Wood in 1741. Platinum occurs as such naturally, together with negligible amounts of palladium, iridium, rhodium, osmium, and ruthenium.