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  2. Negative hyperconjugation in silicon - Wikipedia

    en.wikipedia.org/wiki/Negative_hyperconjugation...

    The continued presence of second-row type stability in certain organosilicon compounds is known as the silicon α and β effects, after the corresponding locants. These stabilities occur because of a partial overlap between the C–Si σ orbital and the σ* antibonding orbital at the β position, lowering the S N reaction transition state 's ...

  3. Negative hyperconjugation - Wikipedia

    en.wikipedia.org/wiki/Negative_hyperconjugation

    Negative hyperconjugation is seldom observed, though it can be most commonly observed when the σ *-orbital is located on certain C–F or C–O bonds. [ 3 ] [ 4 ] In negative hyperconjugation, the electron density flows in the opposite direction (from a π- or p-orbital to an empty σ * -orbital) than it does in the more common ...

  4. Ferrosilicon - Wikipedia

    en.wikipedia.org/wiki/Ferrosilicon

    Ferrosilicon is used as a source of silicon to reduce metals from their oxides and to deoxidize steel and other ferrous alloys. This prevents the loss of carbon from the molten steel (so called blocking the heat); ferromanganese, spiegeleisen, calcium silicides, and many other materials are used for the same purpose. [5]

  5. Electrical steel - Wikipedia

    en.wikipedia.org/wiki/Electrical_steel

    Electrical steel is an iron alloy which may have from zero to 6.5% silicon (Si:5Fe). Commercial alloys usually have silicon content up to 3.2% (higher concentrations result in brittleness during cold rolling). Manganese and aluminum can be added up to 0.5%. [1]

  6. Heavy melting steel - Wikipedia

    en.wikipedia.org/wiki/Heavy_melting_steel

    Heavy melting steel (HMS) or heavy melting scrap is a designation for recyclable steel and wrought iron. It is broken up into two major categories: HMS 1 and HMS 2, where HMS 1 does not contain galvanized and blackened steel, whereas HMS 2 does. The Institute of Scrap Recycling Industries breaks up the categories further: [1]

  7. Hyperconjugation - Wikipedia

    en.wikipedia.org/wiki/Hyperconjugation

    Hyperconjugation can be used to rationalize a variety of chemical phenomena, including the anomeric effect, the gauche effect, the rotational barrier of ethane, the beta-silicon effect, the vibrational frequency of exocyclic carbonyl groups, and the relative stability of substituted carbocations and substituted carbon centred radicals, and the thermodynamic Zaitsev's rule for alkene stability.

  8. Spark testing - Wikipedia

    en.wikipedia.org/wiki/Spark_testing

    Spark testing of tool steel Spark testing of mild steel. Spark testing is a method of determining the general classification of ferrous materials. It normally entails taking a piece of metal, usually scrap, and applying it to a grinding wheel in order to observe the sparks emitted. [1]

  9. Zirconium silicon sulfide - Wikipedia

    en.wikipedia.org/wiki/Zirconium_silicon_sulfide

    Zirconium silicon sulfide (ZrSiS) is a crystalline layered Dirac semi-metal compound of zirconium, silicon and sulfur. [1] Its crystals are made from planes of five single-atom layers of each element in the order S-Zr-Si-Zr-S, with the single element planes connected to their neighbors by van der Waals forces .