crystallographic form
41alkali metal — Chem. any of the group of univalent metals including potassium, sodium, lithium, rubidium, cesium, and francium, whose hydroxides are alkalis. [1880 85] * * * Any of the six chemical elements in the leftmost group of the periodic table (lithium,… …
42nucleic acid — /nooh klee ik, klay , nyooh /, Biochem. any of a group of long, linear macromolecules, either DNA or various types of RNA, that carry genetic information directing all cellular functions: composed of linked nucleotides. [1890 95; NUCLE(US) + IC;… …
43Cyclol — Figure 1: In the classic cyclol reaction, two peptide groups are linked by a N C’ bond, converting the carbonyl oxygen into a hydroxyl group. Although this reaction occurs in a few cyclic peptides, it is disfavored by free energy, mainly because… …
44List of mathematics articles (C) — NOTOC C C closed subgroup C minimal theory C normal subgroup C number C semiring C space C symmetry C* algebra C0 semigroup CA group Cabal (set theory) Cabibbo Kobayashi Maskawa matrix Cabinet projection Cable knot Cabri Geometry Cabtaxi number… …
45Nucleic acid tertiary structure — Example of a large catalytic RNA. The self splicing group II intron from Oceanobacillus iheyensis.[1] The tertiary structure of a nucleic acid is its precise three dimensional structure, as defined by the atomic coordinates.[2] …
46Wafer (electronics) — Polished 12 and 6 silicon wafers. The flat cut into the right wafer indicates its doping and crystallographic orientation (see below) …
47Rock microstructure — includes the texture of a rock and the small scale rock structures. The words texture and microstructure are interchangeable, with the latter preferred in modern geological literature. However, texture is still acceptable because it is a useful… …
48Iridium — (pronEng|ɪˈrɪdiəm) is a chemical element that has the symbol Ir and atomic number 77. A very hard, brittle, silvery white transition metal of the platinum family, iridium is the second densest element and is the most corrosion resistant metal,… …
49Symmetry group — Not to be confused with Symmetric group. This article is about the abstract algebraic structures. For other meanings, see Symmetry group (disambiguation). A tetrahedron can be placed in 12 distinct positions by rotation alone. These are… …
50Coxeter group — In mathematics, a Coxeter group, named after H.S.M. Coxeter, is an abstract group that admits a formal description in terms of mirror symmetries. Indeed, the finite Coxeter groups are precisely the finite Euclidean reflection groups; the symmetry …
