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However the first macroscopic production of carbon nanotubes was made in 1992 by two researchers at NEC's Fundamental Research Laboratory. [3] The method used was the same as in 1991. During this process, the carbon contained in the negative electrode sublimates because of the high-discharge temperatures.
The catalyst was created by carbonization of simple sugars such as glucose and sucrose. The sugars were processed for 15 hours at 400 °C under a nitrogen flow to a black carbon residue consisting of a complex mixture of polycyclic aromatic carbon sheets.
Carbon was not made in the Big Bang, but was produced later in larger stars via the triple-alpha process. The subsequent nucleosynthesis of heavier elements (Z ≥ 6, carbon and heavier elements) requires the extreme temperatures and pressures found within stars and supernovae. These processes began as hydrogen and helium from the Big Bang ...
The metal is capable of forming nanosize carbon structures, and growing nanosize carbon structures by means of a chemical vapor deposition method on the treated carrier in a gas atmosphere comprising a carbon-containing gas, followed by an optional surface modification step. This process allows optimizing porosity, hydrodynamical properties and ...
A carbon nanotube (CNT) is a tube made of carbon with a diameter in the nanometre range . They are one of the allotropes of carbon. Two broad classes of carbon nanotubes are recognized: Single-walled carbon nanotubes (SWCNTs) have diameters around 0.5–2.0 nanometres, about 100,000
Bulk carbon-13 for commercial use, e.g. in chemical synthesis, is enriched from its natural 1% abundance. Although carbon-13 can be separated from the major carbon-12 isotope via techniques such as thermal diffusion, chemical exchange, gas diffusion, and laser and cryogenic distillation, currently only cryogenic distillation of methane (boiling point −161.5°C) or carbon monoxide (b.p. − ...
Carbon's widespread abundance, its ability to form stable bonds with numerous other elements, and its unusual ability to form polymers at the temperatures commonly encountered on Earth enables it to serve as a common element of all known living organisms. In a 2018 study, carbon was found to compose approximately 550 billion tons of all life on ...
Graphite (/ ˈ ɡ r æ f aɪ t /) is a crystalline allotrope (form) of the element carbon. It consists of many stacked layers of graphene, typically in the excess of hundreds of layers. Graphite occurs naturally and is the most stable form of carbon under standard conditions.