In the BN compound analogue of graphite, hexagonal boron nitride (h-BN), the positively charged boron and negatively charged nitrogen atoms in each plane lie adjacent to the oppositely charged atom in the next plane. Cubic boron nitride, among other applications, is used as an abrasive, as it has a hardness comparable with diamond (the two substances are able to produce scratches on each other).
It readily forms hard, stable carbides in alloys, and for this reason most of world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys. Neodymium is not found naturally in metallic form or unmixed with other lanthanides, and it is usually refined for general use.
The chemical symbol for Promethium is Pm. The chemical symbol for Neon is Ne. Cerium is a soft, ductile and silvery-white metal that tarnishes when exposed to air, and it is soft enough to be cut with a knife. Argon is mostly used as an inert shielding gas in welding and other high-temperature industrial processes where ordinarily unreactive substances become reactive; for example, an argon atmosphere is used in graphite electric furnaces to prevent the graphite from burning. Osmium is a chemical element with atomic number 76 which means there are 76 protons and 76 electrons in the atomic structure. Marco Polo brought some glazes back to Italy in the 13th century. These glasses all contain silica or silicate, with varying amounts of oxides of calcium, magnesium, and sometimes boron. In nuclear industry, especially natural and artificial samarium 149 has an important impact on the operation of a nuclear reactor. Though hydrogen bonds are the strongest of the intermolecular forces, the strength of hydrogen bonds is much less than that of ionic bonds. It readily forms hard, stable carbides in alloys, and for this reason most of world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys.
 Boron is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals. In nuclear industry, especially natural and artificial samarium 149 has an important impact on the operation of a nuclear reactor. Thorium is commonly found in monazite sands (rare earth metals containing phosphate mineral). The chemical symbol for Hafnium is Hf.
The neutrons, however, trigger energetic and short-range secondary alpha particle and lithium-7 heavy ion radiation that are products of the boron + neutron nuclear reaction, and this ion radiation additionally bombards the tumor, especially from inside the tumor cells. Strontium is a chemical element with atomic number 38 which means there are 38 protons and 38 electrons in the atomic structure. Zirconium is widely used as a cladding for nuclear reactor fuels.
The formal negative charge of the tetrahedral borate center is balanced by metal cations in the minerals, such as the sodium (Na+) in borax.
Boranes are chemical compounds of boron and hydrogen, with the generic formula of BxHy.
The chemical symbol for Rhenium is Re.
Argon is the third-most abundant gas in the Earth’s atmosphere, at 0.934% (9340 ppmv). Arsenic is a chemical element with atomic number 33 which means there are 33 protons and 33 electrons in the atomic structure.
 Crystalline boron is a very hard, black material with a melting point of above 2000 °C. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity, behind only oxygen and fluorine. As usual, boron is not an element that is intrinsically poisonous, but the toxicity of these compounds depends on structure (for another example of this phenomenon, see phosphine). Neptunium is the first transuranic element.