What is Hexagonal Boron Nitride? Why Is It So Interesting?

Electrical, Physics
Boron, like many other elements, forms nitrides. These nitrides can assume a variety of crystalline structures. One of those varieties consists of atoms in hexagonal array, layered in sheets. It is hexagonal boron nitride, or h-BN. A sheet of h-BN outwardly resembles a sheet of graphene. For this reason, some refer to it as graphitic boron nitride. We shall see that, despite a considerable similarity in appearance on papers, there are major differences between graphene and h-BN as well. Very significant differences. Graphene Vs. Hexagonal Boron Nitride Atomic spacing within a single layer of hexagonal boron nitride varies slightly from that of a sheet of graphene. As a result, graphene is black, while h-BN is white! [caption id="attachment_24819" align="alignleft" width="340"] Powdered h-BN - Image Indiamart[/caption] Graphene's C–C bonds are non-polar…
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Use of the Hull Cell in Maintaining Electroplating and Electroforming Baths

Chemistry, Electrical
[caption id="attachment_23592" align="alignright" width="480"] Hull Cell[/caption] Electroplating is the depositing of a metallic film onto a substrate, whatever form that substrate takes. One most unusual substrate is baby shoes! The electroplating industry contributes both functionally and aesthetically to a host of consumer products. Plating is both a science and an art. Electroplating bath chemistry is crucial. It is dynamic, ever changing. Frequent adjustments, tweaks, keep it in top operating condition. Plating Bath Components Every plating bath is different, but there are some components that are pretty standard for the majority of them. 1. Water 2. Metallic salt 3. An acid or an alkali version of the same salt as the metal 4. Brighteners 5. Anodes Example One example demonstrating the art-science dichotomy is the cyanide-copper flash bath, primarily used in…
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Why Electric Home Heat is So Expensive

Electrical
[caption id="attachment_6041" align="alignright" width="300"] Electric space heater - GNU Free Documentation License 1.2 by aquila2664[/caption] Heat is so expensive! Especially is this so for electric heat. Why? Electricity flowing through a conductor obeys the simple mathematical relationship, E = IR That equation reads: electromotive force (E) equals current (I) times resistance (R). Since the power consumed (P) equals the current times the voltage, P = EI = IR x I = I²R P = I²R This equation informs us that the power consumed by a device is equal to the square of the current (that is, the current times itself, I x I), times the resistance to current flow of the device. If an electrical conductor is very good—for example, a thick copper wire—the power consumed is quite small. This…
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Why Metals Conduct Electricity

Electrical, Physics
[caption id="attachment_19272" align="alignright" width="480"] High Voltage Lines.[/caption] Elements are divided into metals, metalloids, and non-metals. Copper is a metal. Sulfur is a non-metal. Antimony is a metalloid. Why do metals conduct electricity? What makes them special? It involves electron mobility—their ability to move about. Individual Atoms and Diatomic Molecules Atoms have a positive nucleus encased by negative orbiting electrons. Atoms of a single substance either stand alone or bind together in small groups only. Helium (He) is monatomic. Hydrogen (H₂) is diatomic. Ionic and Covalent Crystalline Solids Some solids may form crystals. The atoms are packed close together. There are three crystal types. Ionic, covalent, metallic. Ionic crystals conduct some electricity. They are not as conductive as metals because their bonds are local. Their crystals are rigid. They fracture. They…
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