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Poisson's ratio of a material defines the ratio of transverse strain (x direction) to the axial strain (y direction)In materials science and solid mechanics, Poisson's ratio (symbol: ν ()) is a measure of the Poisson effect, the deformation (expansion or contraction) of a material in directions perpendicular to the specific direction of loading.
Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity (electrowinning). Zinc is an essential trace element for humans, [8] [9] [10] animals, [11] plants [12] and for microorganisms [13] and is necessary for prenatal and postnatal development. [14]
Naturally occurring zinc (30 Zn) is composed of the 5 stable isotopes 64 Zn, 66 Zn, 67 Zn, 68 Zn, and 70 Zn with 64 Zn being the most abundant (48.6% natural abundance).Twenty-eight radioisotopes have been characterised with the most stable being 65 Zn with a half-life of 244.26 days, and then 72 Zn with a half-life of 46.5 hours.
Young's modulus is defined as the ratio of the stress (force per unit area) applied to the object and the resulting axial strain (displacement or deformation) in the linear elastic region of the material. Although Young's modulus is named after the 19th-century British scientist Thomas Young, the concept was developed in 1727 by Leonhard Euler.
A single-displacement reaction, also known as single replacement reaction or exchange reaction, is an archaic concept in chemistry. It describes the stoichiometry of some chemical reactions in which one element or ligand is replaced by atom or group.
It is also known as the stiffness to weight ratio or specific stiffness. High specific modulus materials find wide application in aerospace applications where minimum structural weight is required. The dimensional analysis yields units of distance squared per time squared.
The reaction is effected with zinc. The key zinc-intermediate formed is a carbenoid (iodomethyl)zinc iodide which reacts with alkenes to afford the cyclopropanated product. The rate of forming the active zinc species is increased via ultrasonication since the initial reaction occurs at the surface of the metal.
In materials science, slip is the large displacement of one part of a crystal relative to another part along crystallographic planes and directions. [1] Slip occurs by the passage of dislocations on close/packed planes, which are planes containing the greatest number of atoms per area and in close-packed directions (most atoms per length).