enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Ring (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Ring_(chemistry)

    A ring system that is a simple cycle is called a monocycle or simple ring, and one that is not a simple cycle is called a polycycle or polycyclic ring system. A simple ring contains the same number of sigma bonds as atoms, and a polycyclic ring system contains more sigma bonds than atoms. A molecule containing one or more rings is called a ...

  3. Bredt's rule - Wikipedia

    en.wikipedia.org/wiki/Bredt's_rule

    Bredt's rule is the empirical observation that such molecules only form in large ring systems. For example, two of the following norbornene isomers violate Bredt's rule, and are too unstable to prepare: Bridgehead atoms violating Bredt's rule in red. The rule is named after Julius Bredt, who first discussed it in 1902 [1] and codified it in ...

  4. Diffusion bonding - Wikipedia

    en.wikipedia.org/wiki/Diffusion_bonding

    Diffusion bonding or diffusion welding is a solid-state welding technique used in metalworking, capable of joining similar and dissimilar metals. It operates on the principle of solid-state diffusion, wherein the atoms of two solid, metallic surfaces intersperse themselves over time.

  5. Ring system - Wikipedia

    en.wikipedia.org/wiki/Ring_system

    Artist's depiction of Haumea's ring system. A ring around Haumea, a dwarf planet and resonant Kuiper belt member, was revealed by a stellar occultation observed on 21 January 2017. This makes it the first trans-Neptunian object found to have a ring system. [32] [33] The ring has a radius of about 2,287 km, a width of ≈ 70 km and an opacity of ...

  6. Spiro compound - Wikipedia

    en.wikipedia.org/wiki/Spiro_compound

    A spiro compound, or spirane, from the Latin spīra, meaning a twist or coil, [22] [5]: 1138 [23] is a chemical compound, typically an organic compound, that presents a twisted structure of two or more rings (a ring system), in which 2 or 3 rings are linked together by one common atom, [2]: SP-0

  7. Rotary friction welding - Wikipedia

    en.wikipedia.org/wiki/Rotary_friction_welding

    The results are for example not the same in welds made for the European Space Agency with a high turnover ω = 14000 rpm [61] or another example from Warsaw technical university 12000 rpm [41] and no typical very short friction time only 60 milliseconds [42] instead of using an standard parameters, in addition, in this case, ultra fine grain ...

  8. Ring dike - Wikipedia

    en.wikipedia.org/wiki/Ring_dike

    The Pilanesberg Ring Dike Complex in South Africa. A ring dike or ring dyke is an intrusive igneous body that is circular, oval or arcuate in plan and has steep contacts. [1] While the widths of ring dikes differ, they can be up to several thousand meters. [2] The most commonly accepted method of ring dike formation is directly related to ...

  9. Closed wing - Wikipedia

    en.wikipedia.org/wiki/Closed_wing

    Closed wing designs include the annular wing (commonly known as the cylindrical or ring wing), the joined wing, the box wing, and spiroid tip devices. [ 1 ] Like many wingtip devices , the closed wing aims to reduce the wasteful effects associated with wingtip vortices which occur at the tips of conventional wings.