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Lead Magnesium Niobate
Lead magnesium niobate is a relaxor ferroelectric. It has been used to make piezoelectric microcantilever sensors. References Niobates Magnesium compounds Lead compounds Piezoelectric materials {{electromagnetism-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relaxor Ferroelectric
Relaxor ferroelectrics are ferroelectric materials that exhibit high electrostriction. , although they have been studied for over fifty years, the mechanism for this effect is still not completely understood, and is the subject of continuing research. Examples of relaxor ferroelectrics include: * lead magnesium niobate (PMN) * lead magnesium niobate-lead titanate (PMN-PT) * lead lanthanum zirconate titanate (PLZT) * lead scandium niobate (PSN) *Barium Titanium-Bismuth Zinc Niobium Tantalum (BT-BZNT) *Barium Titanium-Barium Strontium Titanium (BT-BST) Applications Relaxor Ferroelectric materials find application in high efficiency energy storage Energy storage is the capture of energy produced at one time for use at a later time to reduce imbalances between energy demand and energy production. A device that stores energy is generally called an accumulator or battery. Energy comes in ... and conversion as they have high dielectric constants, orders-of-magnitude high ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcantilever
A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a cantilever can be formed as a beam, plate, truss, or slab. When subjected to a structural load at its far, unsupported end, the cantilever carries the load to the support where it applies a shear stress and a bending moment. Cantilever construction allows overhanging structures without additional support. In bridges, towers, and buildings Cantilevers are widely found in construction, notably in cantilever bridges and balconies (see corbel). In cantilever bridges, the cantilevers are usually built as pairs, with each cantilever used to support one end of a central section. The Forth Bridge in Scotland is an example of a cantilever truss bridge. A cantilever in a traditionally timber framed building is called a jetty or forebay. In the souther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium Compounds
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic table) it occurs naturally only in combination with other elements and it almost always has an oxidation state of +2. It reacts readily with air to form a thin passivation coating of magnesium oxide that inhibits further corrosion of the metal. The free metal burns with a brilliant-white light. The metal is obtained mainly by electrolysis of magnesium salts obtained from brine. It is less dense than aluminium and is used primarily as a component in strong and lightweight alloys that contain aluminium. In the cosmos, magnesium is produced in large, aging stars by the sequential addition of three helium nuclei to a carbon nucleus. When such stars explode as supernovas, much of the magnesium is expelled into the interstellar medium where it ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead Compounds
Compounds of lead exist with lead in two main oxidation states: +2 and +4. The former is more common. Inorganic lead(IV) Compound (chemistry), compounds are typically strong oxidants or exist only in highly acidic solutions. Chemistry Various oxidized forms of lead are easily reduced to the metal. An example is heating PbO with mild organic reducing agents such as glucose. The mixture of the oxide and the sulfide heated together will also form the metal. : 2 PbO + PbS → 3 Pb + SO2 Metallic lead is attacked (oxidized) only superficially by air, forming a thin layer of lead oxide that protects it from further oxidation. The metal is not attacked by sulfuric acid, sulfuric or hydrochloric acid, hydrochloric acids. It dissolves in nitric acid with the evolution of nitric oxide gas to form dissolved lead(II) nitrate, Pb(NO3)2. : 3 Pb + 8 H+ + 8 → 3 Pb2+ + 6 + 2 NO + 4 H2O When heated with nitrates of alkali metals, metallic lead oxidizes to form lead(II) oxide, PbO (also k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
