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Calcium graphite CaC 6 is obtained by immersing highly oriented pyrolytic graphite in liquid Li–Ca alloy for 10 days at 350 °C. The crystal structure of CaC 6 belongs to the R 3 m space group. The graphite interlayer distance increases upon Ca intercalation from 3.35 to 4.524 Å, and the carbon-carbon distance increases from 1.42 to 1.444 Å.
Another high-temperature lubricant, hexagonal boron nitride, has the same molecular structure as graphite. It is sometimes called white graphite, due to its similar properties. When a large number of crystallographic defects bind its planes together, graphite loses its lubrication properties and becomes what is known as pyrolytic graphite.
The Laves graph or K 4 crystal is a theoretically predicted three-dimensional crystalline metastable carbon structure in which each carbon atom is bonded to three others, at 120° angles (like graphite), but where the bond planes of adjacent layers lie at an angle of 70.5°, rather than coinciding.
To produce expandable graphite, natural graphite flakes are treated in a bath of acid and oxidizing agent.Usually used oxidizing agents are hydrogen peroxide, potassium permanganate or chromic acid. Concentrated sulphuric acid or nitric acid are usually used as the compound to be incorporated, with the reaction taking place at temperatures of ...
Structure of a protein alpha helix, with stick-figures for the covalent bonding within electron density for the crystal structure at ultra-high-resolution (0.91 Å). The density contours are in gray, the helix backbone in white, sidechains in cyan, O atoms in red, N atoms in blue, and hydrogen bonds as green dotted lines.
Compacted graphite iron (CGI), also known as vermicular graphite iron (GJV, VG, [1] JV [2] or GGV from the German: "Gusseisen mit Vermiculargraphit" [3]) especially in non-English speaking countries, [4] is a metal which is gaining popularity in applications that require either greater strength, or lower weight than cast iron.
In order to properly form the spherical-shaped nodules of graphite (called temper graphite nodules or temper carbon nodules) in the annealing process, care must be taken to ensure that the iron casting will solidify with an entirely white iron cross section. Thicker sections of a casting will cool slowly, allowing some primary graphite to form ...
Graphitization can be observed in various contexts. For example, it occurs naturally during the formation of certain types of coal or graphite in the Earth's crust.It can also be artificially induced during the manufacture of specific carbon materials, such as graphite electrodes used in fuel cells, nuclear reactors or metallurgical applications.