(n.) A solid bounded by eight faces. The regular octahedron is contained by eight equal equilateral triangles.
Example Sentences:
(1) The structure of the activated forms of CF1 can be described best as an intermediate between the dimeric arrangement of latent CF1 and an octahedron.
(2) Location and refinement of the two inequivalent H atoms permitted a detailed analysis of the hydrogen bonding, which occurs principally between the oxygen octahedron and the bromate groups.
(3) The room-temperature structure is very similar to that reported previously for a sample at 169 K. The water O atoms form a very slightly distorted octahedron about nickel while the perbromate-ion geometry is virtually regular tetrahedral.
(4) The central molybdenum atom adopts a distorted octahedral coordination geometry with one face of the octahedron occupied by the tridentate pyrazolylborate ligand and the opposite face by the oxo and the two phenolato ligands.
(5) The coordination environment of the Mg atom is a very nearly regular octahedron of water O atoms.
(6) The quaternary structure of the protein molecule is approximated by a model consisting of six spherical subunits situated at the vertices of an octahedron having the symmetry 32.
(7) The single type of Al ion is coordinated by six inequivalent water O atoms which form a slightly distorted octahedron.
(8) Scanning electron microscopy was employed to elucidate the structure of the crystals, which were found to exist as regular octahedrons ranging in size from 5 to 90 micrometers.
(9) The different spectral forms result from the extent of distortion of the MnIV octahedron.
(10) By computer calculation with the use of atom-atom potentials a stereochemical model of the DNA-hydrate Na+ complex was obtained according to which the Na+(H2O)6 octahedrons are localized in the narrow groove of DNA with formation of a great number of van der vaals contacts and hydrogen bonds.
(11) In the case of artificially produced conjugate containing six cross-linked CT molecules, this is observed at Wo = 43 when rc is equal to the radius of the sphere surrounding the absolute octahedron composed of six CT globules.
(12) In one simulation, one alpha-cyclodextrin form in a "truncated octahedron box" containing 611 water molecules is simulated over 90 picoseconds to mimic the solution structure.
(13) The average Al--O distance within the octahedron is 1.872 (11) A.
Tetrahedron
Definition:
(n.) A solid figure inclosed or bounded by four triangles.
Example Sentences:
(1) In order to increase understanding of the control of inositol-1,3,4-trisphosphate kinase activity, the enzyme was highly purified from rat liver by precipitation with polyethylene glycol, MonoQ ion-exchange chromatography, heparin-agarose affinity chromatography, and a novel affinity chromatography procedure that utilized Affi-Gel resin to which InsP6 was coupled (Marecek, J.F., and Prestwich, G.D. (1991) Tetrahedron Lett.
(2) The folding of murine interleukin-1 beta is similar to that found for the human variant, consisting of 12 beta strands wrapped around a core of hydrophobic side chains in a tetrahedron-like fashion.
(3) The anion [Cd(DiMeDMSA)2]2- is essentially a distorted tetrahedron, with a mononuclear CdS4 kernel.
(4) If you're a researcher in any academic discipline, your reputation and career prospects are largely determined by your publications in journals of mind-bending specialisation – like Tetrahedron , a journal specialising in organic chemistry and published by the Dutch company Elsevier.
(5) Six shapes (ring, tetrahedron, cloverleaf, disk, string, and pellet) were screened in vivo for their gastric retention potential.
(6) 124, 107-115; Lowe (1976) Tetrahedron 32, 291-302] were based on assumed models that are not consistent with the X-ray-diffraction data for papain inhibited by alkylation of Cys-25 with N-benzyloxycarbonyl-Phe-Ala-chloromethane [Drenth, Kalk & Swen (1976) Biochemistry 15, 3731-3738].
(7) Reporting a set of bile samples on the tetrahedron of concentrations, a clear separation emerged between the control bile, the bile from patients with gallstones, and the bile of subjects with gallbladder dyskinesia.
(8) [1975), Tetrahedron Lett., 25, 2065-2068) and MAOP was synthesized by acetoxylation of MOP with lead tetraacetate.
(9) We have examined the mechanism of action of two natural products identified as broad spectrum antifungal agents (VanMiddlesworth, F., Dufresne, C., Wincott, F. E., Mosley, R. T., and Wilson, K. E. (1992) Tetrahedron Lett., in press; VanMiddlesworth, F., Giacobbe, R. A., Lopez, M. Garrity, G., Bland, J.
(10) Using an in vitro system of bubbles in water or gelatin, it was found that the ring-down artifact originated from the center of a cluster of four bubbles (bubble tetrahedron), three on top and one nestled beneath.
(11) The catalase molecule consists of four subunits whose centers from a fairly flattened tetrahedron.
(12) The observation of occasional triangular and dual-intensity projections and the interconversion of all three projection forms in tilting studies indicates that this tetrameric enzyme has a structure very similar to the tetrahedron-like configuration previously proposed for pyruvate carboxylases from vertebrate sources [Mayer, F., Wallace, J. C. and Keech, D. B.
(13) RV volume was calculated from the polyhedron created by the markers by decomposing the polyhedron into 24 tetrahedrons, each of whose volumes could be solved from the xyz-coordinates of markers.
(14) (1990, Tetrahedron 46, 2255) as an inhibitor of human leucocyte elastase (HLE) displayed potent, time-dependent inhibition of both HLE and human cathepsin G (Cat-G).
(15) The figure of tetrahedron is formed in certain species of Plectus and in Tobrilus gracilis at the stage of 4 blastomeres rather than a rhombus which is formed in most highly organized nematodes.
(16) A tetrahedronal symmetry is exploited, with two skewed plastic scintillator bars spanning a large sensitive volume.
(17) The tetrahedrons (each leg 2 cm in length) exhibited 91-100% retention at 24 hr.
(18) Altogether, the in vitro binding constant of seven molecules were used to deduce the geometry and the energetics of a possible site model consisting of five regions: one tetrahedron-shaped finite central hydrophobic pocket, one infinite region representing access to the solvent, and three strongly repulsive regions representing the sterically forbidden walls of the pocket.
(19) Phaseolin converts to an 18 S tetramer at acid pH, and images recorded under these conditions suggest that four of the 7 S protomer discs associate to form the faces of a regular tetrahedron.
(20) The volumes defined by four beads (a tetrahedron) at end diastole showed increases in myocardial mass of 20-27% after 3.6 (mean) weeks of hypertrophy and were uniform across the wall of the left ventricle.