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Sample records for crystal adjacent mol-ecules

  1. Crystal structure of a 2:1 piroxicam-gentisic acid co-crystal featuring neutral and zwitterionic piroxicam mol-ecules.

    Science.gov (United States)

    Horstman, Elizabeth M; Bertke, Jeffery A; Woods, Toby J; Kenis, Paul J A

    2016-12-01

    A new 2:1 co-crystal of piroxicam and gentisic acid [systematic name: 4-hy-droxy-1,1-dioxo-N-(pyridin-2-yl)-2H-1λ(6),2-benzo-thia-zine-3-carboxamide-2-(4-oxido-1,1-dioxo-2H-1λ(6),2-benzo-thia-zine-3-amido)-pyridin-1-ium-2,5-di-hydroxy-benzoic acid, 2C15H13N3O4S·C7H6O4] has been synthesized using a microfluidic platform and initially identified using Raman spectroscopy. In the co-crystal, one piroxicam mol-ecule is in its neutral form and an intra-molecular O-H⋯O hydrogen bond is observed. The other piroxicam mol-ecule is zwitterionic (proton transfer from the OH group to the pyridine N atom) and two intra-molecular N-H⋯O hydrogen bonds occur. The gentisic acid mol-ecule shows whole-mol-ecule disorder over two sets of sites in a 0.809 (2):0.191 (2) ratio. In the crystal, extensive hydrogen bonding between the components forms layers propagating in the ab plane.

  2. Crystal structure of 5-amino-5'-chloro-6-(4-chloro-benzo-yl)-8-nitro-2,3-di-hydro-1H-spiro-[imidazo[1,2-a]pyridine-7,3'-indolin]-2'-one including an unknown solvent mol-ecule.

    Science.gov (United States)

    Nagalakshmi, R A; Suresh, J; Sivakumar, S; Kumar, R Ranjith; Lakshman, P L Nilantha

    2014-09-01

    The asymmetric unit of the title compound, C21H15Cl2N5O4, contains two independent mol-ecules (A and B) having similar conformations. The amine (NH2) group forms an intra-molecular hydrogen bond with the benzoyl group, giving an S(6) ring motif in both mol-ecules. The central six-membered rings adopt sofa conformations and the imidazole rings are planar (r.m.s deviations = 0.0150 and 0.0166 Å). The pyridine and imidazole rings are inclined to one another by 3.54 (1) and 3.03 (1)° in mol-ecules A and B, respectively. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming chains along the a axis which enclose R 2 (2)(16) ring motifs. The rings are linked by weak N-H⋯O and C-H⋯O hydrogen bonds and C-H⋯π inter-actions forming sheets lying parallel to (001). A region of disordered electron density, most probably disordered solvent mol-ecules, occupying voids of ca 753 Å(3) for an electron count of 260, was treated using the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. Their formula mass and unit-cell characteristics were not taken into account during refinement.

  3. Crystal structure of cis-bis-{4-phenyl-1-[(3R)-1,7,7-tri-methyl-2-oxobi-cyclo-[2.2.1]heptan-3-ylidene]thio-semicarbazidato-κ(3) O,N (1),S}cadmium(II) with an unknown solvent mol-ecule.

    Science.gov (United States)

    Nogueira, Vanessa Senna; Bresolin, Leandro; Näther, Christian; Jess, Inke; de Oliveira, Adriano Bof

    2015-12-01

    The reaction between the racemic mixture of the camphor-4-phenyl-thio-semicarbazone derivative and cadmium acetate dihydrate yielded the title compound, [Cd(C17H20N3OS)2]. The Cd(II) ion is six-coordinated in a distorted octa-hedral environment by two deprotonated thio-semicarbazone ligands acting as an O,N,S-donor in a tridentate chelating mode, forming five-membered chelate rings. In the crystal, the mol-ecules are connected via pairs of N-H⋯S and C-H⋯S inter-actions, building centrosymmetric dimers. One of the ligands is disordered in the campher unit over two sets of sites with site-occupancy factors of 0.7 and 0.3. The structure contains additional solvent mol-ecules, which are disordered and for which no reasonable split model was found. Therefore, the data were corrected for disordered solvent using the SQUEEZE routine [Spek (2015 ▸). Acta Cryst. C71, 9-18] in PLATON. Since the disordered solvents were removed by data processing, and the number of solvent entities was a suggestion only, they were not considered in the chemical formula and subsequent chemical or crystal information.

  4. Crystal structure of N-(4-oxo-2-sulfanyl-idene-1,3-thia-zolidin-3-yl)-2-(thio-phen-3-yl)acetamide.

    Science.gov (United States)

    Vu Quoc, Trung; Nguyen Ngoc, Linh; Nguyen Tien, Cong; Thang Pham, Chien; Van Meervelt, Luc

    2017-06-01

    The title compound, C9H8N2O2S3, crystallizes with two mol-ecules (A and B) in the asymmetric unit. Both have similar conformations (overlay r.m.s. deviation = 0.209 Å) and are linked by an N-H⋯O hydrogen bond. In both mol-ecules, the thio-phene rings show orientational disorder, with occupancy factors of 0.6727 (17) and 0.3273 (17) for mol-ecule A, and 0.7916 (19) and 0.2084 (19) for mol-ecule B. The five-membered rings make an angle of 79.7 (2)° in mol-ecule A and an angle of 66.8 (2)° in mol-ecule B. In the crystal, chains of mol-ecules running along the a-axis direction are linked by N-H⋯O hydrogen bonds. The inter-action of adjacent chains through N-H⋯O hydrogen bonds leads to two types of ring structures containing four mol-ecules and described by the graph-set motifs R4(4)(18) and R4(2)(14).

  5. Crystal structures of three N-(aryl-sulfon-yl)-4-fluoro-benzamides.

    Science.gov (United States)

    Suchetan, P A; Naveen, S; Lokanath, N K; Srivishnu, K S; Supriya, G M; Lakshmikantha, H N

    2016-04-01

    The crystal structures of three N-aryl-sulfonyl-4-fluoro-benzamides, namely 4-fluoro-N-(2-methyl-phenyl-sulfon-yl)benzamide, C14H12FNO3S, (I), N-(2-chloro-phenyl-sulfon-yl)-4-fluorobenzamide, C13H9ClFNO3S, (II), and N-(4-chloro-phenyl-sulfon-yl)-4-fluoro-benzamide monohydrate, C13H9ClFNO3S·H2O, (III), are described and compared with related structures. The asymmetric unit of (I) contains two independent mol-ecules (A and B), while that of (II) contains just one mol-ecule, and that of (III) contains a mol-ecule of water in addition to one main mol-ecule. The dihedral angle between the benzene rings is 82.83 (11)° in mol-ecule A and 85.01 (10)° in mol-ecule B of (I), compared to 89.91 (10)° in (II) and 81.82 (11)° in (III). The crystal structure of (I) features strong N-H⋯O hydrogen bonds between the A and B mol-ecules, resulting in an R 4 (4)(16) tetra-meric unit. These tetra-meric units are connected into sheets in the bc plane by various C-H⋯O inter-actions, and adjacent sheets are further inter-linked via C-H⋯πar-yl inter-actions, forming a three-dimensional architecture. The crystal structure is further stabilized by πar-yl-πar-yl and S=O⋯πar-yl inter-actions. In the crystal of (II), mol-ecules are connected into R 2 (2)(8) and R 2 (2)(14) dimers via N-H⋯O hydrogen bonds and C-H⋯O inter-actions, respectively; the dimers are further inter-connected via a weak C=O⋯πar-yl inter-action, leading to the formation of chains along [1-10]. In the crystal of (III), N-H⋯O and O-H⋯O hydrogen bonds involving both the main mol-ecule and the solvent water mol-ecule results in the formation of sheets parallel to the bc plane. The sheets are further connected by C-H⋯O inter-actions and weak C-Cl⋯πar-yl, C-F⋯πar-yl and S=O⋯πar-yl inter-actions, forming a three-dimensional architecture.

  6. Crystal structure of catena-poly[[di-aqua-cobalt(II)]-bis-[μ-5-(4-carb-oxy-ylato-phenyl)picolinato]-κ(3) N,O (2):O (5);κ(3) O (5):N,O (2)-[di-aqua-cobalt(II)]-μ-1-[4-(1H-imidazol-1-yl)phen-yl]-1H-imidazole-κ(2) N (3):N (3')].

    Science.gov (United States)

    Xu, Guo-Wang; Wang, Ye-Nan; Wang, Hai-Bing; Wang, Zhong-Long

    2015-07-01

    The asymmetric unit of the title polymeric Co(II) complex, [Co2(C13H7NO4)2(C12H10N4)(H2O)4] n , contains a Co(II) cation, a 5-(4-carboxyl-atophen-yl)picolinate dianion, two coordination water mol-ecules and half of 1-[4-(1H-imidazol-1-yl)phen-yl]-1H-imidazole ligand. The Co(II) cation is coordinated by two picolinate dianions, two water mol-ecules and one 1-[4-(1H-imidazol-1-yl)phen-yl]-1H-imidazole mol-ecule in a distorted N2O4 octa-hedral coordination geometry. The two picolinate dianions are related by an inversion centre and link two Co(II) cations, forming a binuclear unit, which is further bridged by the imidazole mol-ecules, located about an inversion centre, into the polymeric chain propagating along the [-1-11] direction. In the crystal, the three-dimensional supra-molecular architecture is constructed by O-H⋯O hydrogen bonds between the coordinating water mol-ecules and the non-coordinating carboxyl-ate O atoms of adjacent polymeric chains.

  7. Crystal structure of N-[(4-eth-oxy-phen-yl)carbamo-thio-yl]cyclo-hexa-ne-carboxamide.

    Science.gov (United States)

    Vimala, G; Haribabu, J; Srividya, S; Karvembu, R; SubbiahPandi, A

    2015-11-01

    The asymmetric unit of the title compound, C16H22N2O2S, contains two crystallographically independent mol-ecules (A and B). In mol-ecule A, the cyclo-hexane ring is disordered over two orientations [occupancy ratio 0.841 (10):0.159 (10)]. In each mol-ecule, the central carbonyl thio-urea unit is nearly planar (r.m.s. deviations for all non-H atoms of 0.034 Å in mol-ecule A and 0.094 Å in mol-ecule B). In both mol-ecules, the cyclo-hexane ring adopts a chair conformation. The mean plane of the cyclo-hexane ring makes dihedral angles of 35.8 (4) (mol-ecule A) and 20.7 (3)° (mol-ecule B) with that of the benzene ring. Each mol-ecule features an intra-molecular N-H⋯O hydrogen bond, which closes an S(6) ring motif. In the crystal, mol-ecules are linked via pairs of weak N-H⋯S inter-actions, forming inversion dimers with an R 2 (2)(8) ring motif for both mol-ecules. The crystal structure also features weak C-H⋯π ring inter-actions.

  8. Crystal structure of (E)-2-[(2-bromopyridin-3-yl)methyl-idene]-6-meth-oxy-3,4-di-hydro-naphthalen-1(2H)-one and 3-[(E)-(6-meth-oxy-1-oxo-1,2,3,4-tetra-hydro-naphthalen-2-ylidene)meth-yl]pyridin-2(1H)-one.

    Science.gov (United States)

    Zingales, Sarah K; Moore, Morgan E; Goetz, Andrew D; Padgett, Clifford W

    2016-07-01

    The title compounds C17H14BrNO2, (I), and C17H15NO3, (II), were obtained from the reaction of 6-meth-oxy-3,4-di-hydro-2H-naphthalen-1-one and 2-bromo-nicotinaldehyde in ethanol. Compound (I) was the expected product and compound (II) was the oxidation product from air exposure. In the crystal structure of compound (I), there are no short contacts or hydrogen bonds. The structure does display π-π inter-actions between adjacent benzene rings and adjacent pyridyl rings. Compound (II) contains two independent mol-ecules, A and B, in the asymmetric unit; both are non-planar, the dihedral angles between the meth-oxy-benzene and 1H-pyridin-2-one mean planes being 35.07 (9)° in A and 35.28 (9)°in B. In each mol-ecule, the 1H-pyridin-2-one unit participates in inter-molecular N-H⋯O hydrogen bonding to another mol-ecule of the same type (A to A or B to B). The structure also displays π-π inter-actions between the pyridyl and the benzene rings of non-equivalent mol-ecules (viz., A to B and B to A).

  9. Channels with ordered water and bipyridine mol-ecules in the porous coordination polymer {[Cu(SiF6)(C10H8N2)2]·2C10N2H8·5H2O} n.

    Science.gov (United States)

    Aubert, Emmanuel; Doudouh, Abdelatif; Peluso, Paola; Mamane, Victor

    2016-11-01

    The coordination polymer {[Cu(SiF6)(C10H8N2)2]·2C10H8N2·5H2O} n , systematic name: poly[[bis-(μ2-4,4'-bi-pyridine)(μ2-hexa-fluorido-silicato)copper(II)] 4,4'-bi-pyridine disolvate penta-hydrate], contains pores which are filled with water and 4,4'-bi-pyridine mol-ecules. As a result of the presence of these ordered species, the framework changes its symmetry from P4/mmm to P21/c. The 4,4'-bi-pyridine guest mol-ecules form chains inside the 6.5 × 6.9 Å pores parallel to [100] in which the mol-ecules inter-act through π-π stacking. Ordered water mol-ecules form infinite hydrogen-bonded chains inside a second pore system (1.6 × 5.3 Å free aperture) perpendicular to the 4,4'-bi-pyridine channels.

  10. Crystal and mol-ecular structure of meso-2,6-di-bromo-hepta-nedioic acid (meso-2,6-di-bromo-pimelic acid).

    Science.gov (United States)

    Dirda, Nathaniel D A; Zavalij, Peter Y; Kao, Joseph P Y

    2016-03-01

    The mol-ecular structure of the title compound, C7H10Br2O4, confirms the meso (2R,6S) configuration. In the crystal, mol-ecules are linked by pairs of O-H⋯O=C hydrogen bonds between their terminal carboxyl groups in an R 2 (2)(8) motif, forming extended chains that propagate parallel to the c axis. Adjacent chains are linked by C=O⋯Br halogen bonds.

  11. Nonlinear spin wave coupling in adjacent magnonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sadovnikov, A. V., E-mail: sadovnikovav@gmail.com; Nikitov, S. A. [Laboratory “Metamaterials,” Saratov State University, Saratov 410012 (Russian Federation); Kotel' nikov Institute of Radioengineering and Electronics, Russian Academy of Sciences, Moscow 125009 (Russian Federation); Beginin, E. N.; Morozova, M. A.; Sharaevskii, Yu. P.; Grishin, S. V.; Sheshukova, S. E. [Laboratory “Metamaterials,” Saratov State University, Saratov 410012 (Russian Federation)

    2016-07-25

    We have experimentally studied the coupling of spin waves in the adjacent magnonic crystals. Space- and time-resolved Brillouin light-scattering spectroscopy is used to demonstrate the frequency and intensity dependent spin-wave energy exchange between the side-coupled magnonic crystals. The experiments and the numerical simulation of spin wave propagation in the coupled periodic structures show that the nonlinear phase shift of spin wave in the adjacent magnonic crystals leads to the nonlinear switching regime at the frequencies near the forbidden magnonic gap. The proposed side-coupled magnonic crystals represent a significant advance towards the all-magnonic signal processing in the integrated magnonic circuits.

  12. Crystal structure of 1-benzyl-3-methyl-1H-imidazolium hexa-fluorido-phosphate.

    Science.gov (United States)

    Hillesheim, Patrick C; Scipione, Kent A

    2014-12-01

    In the title salt, C11H13N2 (+)·PF6 (-), the dihedral angle between the planes of the imidazole and benzene rings is 84.72 (4)°. In the crystal, C-H⋯F inter-actions connect the cation and anion pairs into a three-dimensional network. Weak π-π inter-actions are observed between the imidazolium ring and the aromatic benzene ring of an adjacent mol-ecule with C⋯C and C⋯N distances ranging from 3.3714 (16) to 3.4389 (15) Å.

  13. Crystal structure of γ-ethyl-l-glutamate N-carb-oxy anhydride.

    Science.gov (United States)

    Kanazawa, Hitoshi; Inada, Aya

    2015-01-01

    In the title compound (alternative name N-carboxy-l-glutamic anhydride γ-ethyl ester), C8H11NO5, the oxazolidine ring is essentially planar, with a maximum deviation of 0.019 (2) Å. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds between the imino group and the carbonyl O atom in the ethyl ester group, forming a tape structure along the c-axis direction. The oxazolidine rings of adjacent tapes are arranged into a layer parallel to the ac plane. This arrangement is favourable for the polymerization of the title compound in the solid state.

  14. Crystal structure of canagliflozin hemihydrate.

    Science.gov (United States)

    Liu, Kai-Hang; Gu, Jian-Ming; Hu, Xiu-Rong; Tang, Gu-Ping

    2016-05-01

    There are two canagliflozin mol-ecules (A and B) and one water mol-ecule in the asymmetric unit of the title compound, C24H25FO5S·0.5H2O [systematic name: (2S,3R,4R,5S,6R)-2-(3-{[5-(4-fluoro-phen-yl)thio-phen-2-yl]meth-yl}-4-methylphen-yl)-6-(hy-droxy-meth-yl)-3,4,5,6-tetra-hydro-2H-pyran-3,4,5-triol hemihydrate]. The dihedral angles between the methyl-benzene and thio-phene rings are 115.7 (4) and 111.7 (4)°, while the dihedral angles between the fluoro-benzene and thio-phene rings are 24.2 (6) and 20.5 (9)° in mol-ecules A and B, respectively. The hydro-pyran ring exhibits a chair conformation in both canagliflozin mol-ecules. In the crystal, the canagliflozin mol-ecules and lattice water mol-ecules are connected via O-H⋯O hydrogen bonds into a three-dimensional supra-molecular architecture.

  15. Crystal structure of (E)-4-hy-droxy-N'-(3-meth-oxy-benzyl-idene)benzohydrazide.

    Science.gov (United States)

    Chantrapromma, Suchada; Prachumrat, Patcharawadee; Ruanwas, Pumsak; Boonnak, Nawong; Kassim, Mohammad B

    2016-09-01

    The title compound, C15H14N2O3, crystallizes with two independent mol-ecules (A and B) in the asymmetric unit that differ in the orientation of the 3-meth-oxy-phenyl group with respect to the methyl-idenebenzohydrazide unit. The dihedral angles between the two benzene rings are 24.02 (10) and 29.30 (9)° in mol-ecules A and B, respectively. In mol-ecule A, the meth-oxy group is twisted slightly relative to its bound benzene ring, with a Cmeth-yl-O-C-C torsion angle of 14.2 (3)°, whereas it is almost co-planar in mol-ecule B, where the corresponding angle is -2.4 (3)°. In the crystal, the mol-ecules are linked by N-H⋯O, O-H⋯N and O-H⋯O hydrogen bonds, as well as by weak C-H⋯O inter-actions, forming sheets parallel to the bc plane. The N-H⋯O hydrogen bond and weak C-H⋯O inter-action link different mol-ecules (A⋯B) whereas both O-H⋯N and O-H⋯O hydrogen bonds link like mol-ecules (A⋯A) and (B⋯B). Pairs of inversion-related B mol-ecules are stacked approximately along the a axis by π-π inter-actions in which the distance between the centroids of the 3-meth-oxy-phenyl rings is 3.5388 (12) Å. The B mol-ecules also participate in weak C-H⋯π inter-actions between the 4-hy-droxy-phenyl and the 3-meth-oxy-phenyl rings.

  16. Methyl-phospho-nic acid, CH3PO(OH)2.

    Science.gov (United States)

    Reuter, Hans; Reichelt, Martin

    2014-03-01

    The asymmetric unit of the title compound, CH5O3P, contains two independent mol-ecules with nearly identical bond lengths and angles. In the crystal, each of the mol-ecules acts as acceptor (P=O) and donor (P-OH) of four hydrogen bonds to three adjacent mol-ecules, resulting in the formation of two different bilayers (one for each mol-ecule) stacked perpendicular to the a axis in the crystal.

  17. Crystal structure of dimethyl 3,4,5,6-tetra-phenyl-cyclo-hexa-3,5-diene-1,2-di-carboxyl-ate.

    Science.gov (United States)

    Greenberg, Fred H; Nazarenko, Alexander Y

    2016-07-01

    In the title compound, C34H28O4, the cyclo-hexa-diene ring has a screw-boat conformation with a torsion angle between the double bonds being on average ca 15° [15.2 (3) and -15.3 (3) in the two independent mol-ecules]. All four phenyl rings in both mol-ecules are arranged in a propeller-like conformation. The two mol-ecules exhibit S,R- and R,S- chirality, respectively, and are connected via C-H⋯O inter-molecular inter-actions. In turn, these weakly bound dimers form the mol-ecular crystal.

  18. Crystal structure of μ6-chlorido-nona-kis-(μ-4-chloro-pyrazolato)bis-μ3-methoxo-hexa-copper(II).

    Science.gov (United States)

    Shi, Kaige; Mathivathanan, Logesh; Raptis, Raphael G

    2017-02-01

    The hexa-nuclear title compound, [{Cu3(μ3-OCH3)(μ-C3H2ClN2)3}2(μ-C3H2ClN2)3(μ6-Cl)] or [Cu6(C3H2ClN2)9(CH3O)2Cl], crystallizes in the space group Pbcn, with individual mol-ecules being located on a twofold rotation axis. The mol-ecule adopts a trigonal prismatic shape, with two trinuclear units linked by three 4-chloro-pyrazolate ligand bridges by encapsulating a Cl(-) anion in a μ6-coordination mode. In the crystal, individual mol-ecules are stacked into rods parallel to [1-10] that are arranged in a pseudo-hexa-gonal packing. Cohesion between mol-ecules is accomplished through weak C-H⋯Cl inter-actions.

  19. Crystal structure of bis-{4-bromo-2-[(carb-amim-id-amido-imino)-meth-yl]phenolato-κ(3) N,N',O}cobalt(III) nitrate di-methyl-formamide monosolvate.

    Science.gov (United States)

    Buvaylo, Elena A; Kasyanova, Katerina A; Vassilyeva, Olga Yu; Skelton, Brian W

    2016-07-01

    The title compound, [Co(C8H8BrN4O)2]NO3·C3H7NO, is formed of discrete [CoL 2](+) cations, nitrate anions and di-methyl-formamide (DMF) mol-ecules of crystallization. The cation has no crystallographically imposed symmetry. The ligand mol-ecules are deprotonated at the phenol O atom and octa-hedrally coordinate the Co(III) atoms through the azomethine N and phenolate O atoms in a mer configuration. The deprotonated ligand mol-ecules adopt an almost planar conformation. In the crystal lattice, the cations are arranged in layers in the ab plane divided by the nitrate anions and solvent mol-ecules. No π-π stacking is observed. All of the amine H atoms are involved in hydrogen bonding to nitrate, DMF or ligand O atoms or to one of the Br atoms, forming two-dimensional networks parallel to (100).

  20. Crystal structure of (E)-N-{[3-methyl-1-phenyl-5-(1H-pyrrol-1-yl)-1H-pyrazol-4-yl]methyl-idene}hydroxyl-amine.

    Science.gov (United States)

    Mague, Joel T; Mohamed, Shaaban K; Akkurt, Mehmet; El-Emary, Talaat I; Albayati, Mustafa R

    2014-11-01

    The title compound, C15H14N4O, crystallizes with two mol-ecules in the asymmetric unit with similar conformations (r.m.s. overlay fit for the 20 non-H atoms = 0.175 Å). In the first mol-ecule, the dihedral angles between the planes of the central pyrazole ring and the pendant phenyl and pyrrole rings are 42.69 (8) and 51.88 (6)°, respectively, with corresponding angles of 54.49 (7) and 49.61 (9)°, respectively, in the second mol-ecule. In the crystal, the two mol-ecules, together with their inversion-symmetry counterparts, are linked into tetra-mers by O-H⋯N hydrogen bonds. The tetra-mers form layers parallel to (211) through pairwise C-H⋯π inter-actions.

  1. Crystal structure of cis-2-(2-carb-oxy-cyclo-prop-yl)glycine (CCG-III) monohydrate.

    Science.gov (United States)

    Lindeman, Sergey; Wallock, Nathaniel J; Donaldson, William A

    2015-07-01

    The title compound, C6H9NO4·H2O [systematic name: (αR,1R,2S)-rel-α-amino-2-carb-oxy-cyclo-propane-acetic acid monohydrate], crystallizes with two organic mol-ecules and two water mol-ecules in the asymmetric unit. The space group is P21 and the organic mol-ecules are enanti-omers, thus this is an example of a 'false conglomerate' with two mol-ecules of opposite handedness in the asymmetric unit (r.m.s. overlay fit = 0.056 Å for one mol-ecule and its inverted partner). Each mol-ecule exists as a zwitterion, with proton transfer from the amino acid carb-oxy-lic acid group to the amine group. In the crystal, the components are linked by N-H⋯O and O-H⋯O hydrogen bonds, generating (100) sheets. Conformationally restricted glutamate analogs are of inter-est due to their selective activation of different glutamate receptors, and the naturally occurring (+)-CCG-III is an inhibitor of glutamate uptake and the key geometrical parameters are discussed.

  2. Crystal structure of 6,6,12,12-tetra-chloro-tri-cyclo-[8.2.0.0(4,7)]dodecane-5,11-dione.

    Science.gov (United States)

    Turan Akın, Esra; Hökelek, Tuncer

    2015-09-01

    The asymmetric unit of the title compound, C12H12Cl4O2, contains two crystallographically independent mol-ecules with almost identical conformations (r.m.s. overlay fit for the non-hydrogen atoms = 0.059 Å). In each mol-ecule, the central eight-membered ring has a distorted boat configuration, and two non-planar four-membered rings are fused on either side of the eight-membered ring. A weak C-H⋯O hydrogen bond links the two independent mol-ecules. In the crystal, weak C-H⋯O hydrogen bonds link the mol-ecules into a two-dimensional network parallel to (001).

  3. Crystal structure of 2-(2-amino-phen-yl)-1,3-benzoxazole.

    Science.gov (United States)

    Pérez-Pérez, Imelda; Martínez-Otero, Diego; Rojas-Lima, Susana; López-Ruiz, Heraclio

    2015-02-01

    Crystals of the title compound, C13H10N2O, were grown from a di-chloro-methane/ketone/methanol solvent mixture. It crystallizes with two mol-ecules, A and B, in the asymmetric unit with very similar almost planar conformations [dihedral angles between the ring planes = 0.74 (8) and 0.67 (6)° for mol-ecules A and B, respectively; r.m.s. overlay fit = 0.019 Å]. Each mol-ecule features an intra-molecular N-H⋯N hydrogen bond, which closes an S(6) ring and therefore establishes a syn relationship for the N atoms. In the crystal, mol-ecules are linked by N-H⋯N hydrogen bonds, generating [100] chains containing alternating A and B mol-ecules. Weak aromatic π-π stacking [minimum centroid-centroid separation = 3.6212 (9) Å] links the chains into a three-dimensional network.

  4. Crystal structure of O-benzyl-l-tyrosine N-carb-oxy anhydride.

    Science.gov (United States)

    Inada, Aya; Kanazawa, Hitoshi

    2017-04-01

    In the title compound, C17H15NO4 (alternative name; O-benzyl-l-tyrosine N-carb-oxy anhydride), the oxazolidine ring is planer, with an r.m.s. deviation of 0.039 Å. The benz-yloxy and benzyl rings are almost coplanar, making a dihedral angle of 0.078 (10)°, and are inclined to the oxazolidine ring by 59.16 (11) and 58.42 (11)°, respectively. In the crystal, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen bonds, forming ribbons propagating along [010]. The ribbons are linked by C-H⋯π inter-actions, forming a three-dimensional supra-molecular structure. The oxazolidine rings of adjacent ribbons are arranged into a layer parallel to the ab plane. This arrangement is favourable for the polymerization of the compound in the solid state.

  5. Crystal structure of 2,2-di-chloro-1-(piperidin-1-yl)butane-1,3-dione.

    Science.gov (United States)

    Schwierz, Markus; Görls, Helmar; Imhof, Wolfgang

    2015-01-01

    In the title compound, C9H13Cl2NO2, the piperidine ring shows a chair conformation and the O-C-C-O torsion angle between the carbonyl groups is 183.6 (4)°. In the crystal, mol-ecules are linked into an infinite layer along the ab plane by a bifurcated C-H⋯O hydrogen bond between the carbonyl O atom adjacent to the methyl group and one of the methyl-ene groups next to nitro-gen and an additional hydrogen bond of the C-H⋯Cl type. These layers are connected into a three-dimensional supra-molecular arrangement by O⋯Cl contacts [2.8979 (12) and 3.1300 (12) Å].

  6. Crystal structure of 1,1'-[imidazolidine-1,3-diylbis(methyl-ene)]bis-(naphthalen-2-ol).

    Science.gov (United States)

    Rivera, Augusto; Rojas, Jicli José; Ríos-Motta, Jaime; Bolte, Michael

    2015-03-01

    The crystal structure of the title compound, C25H24N2O2, at 173 K has monoclinic (C2/c) symmetry. The mol-ecule is located on a crystallographic twofold rotation axis with only half a mol-ecule in the asymmetric unit. The imidazolidine ring adopts a twist conformation, with a twist about the ring C-C bond. The crystal structure shows the anti-clinal disposition of the two (2-hy-droxy-naphthalen-1-yl)methyl substituents of the imidazolidine ring. The structure displays two intra-molecular O-H⋯N hydrogen bonds, each forming an S(6) ring motif.

  7. Crystal structure of benzyl (E)-2-(3,4-di-meth-oxy-benzyl-idene)hydrazine-1-carbodi-thio-ate.

    Science.gov (United States)

    Tan, Yew-Fung; Break, Mohammed Khaled Bin; Tahir, M Ibrahim M; Khoo, Teng-Jin

    2015-02-01

    The title compound, C17H18N2O2S2, synthesized via a condensation reaction between S-benzyl di-thio-carbazate and 3,4-di-meth-oxy-benzaldehyde, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. Both mol-ecules have an L-shape but differ in the orientation of the benzyl ring with respect to the 3,4-di-meth-oxy-benzyl-idine ring, this dihedral angle is 65.59 (8)° in mol-ecule A and 73.10 (8)° in mol-ecule B. In the crystal, the A and B mol-ecules are linked via pairs of N-H⋯S hydrogen bonds, forming dimers with an R 2 (2)(8) ring motif. The dimers are linked via pairs of C-H⋯O hydrogen bonds, giving inversion dimers of dimers. These units are linked by C-H⋯π inter-actions, forming ribbons propagating in the [100] direction.

  8. Crystal structure of a 2:1 co-crystal of meloxicam with acetyl-endi-carb-oxy-lic acid.

    Science.gov (United States)

    Tantardini, Christian; Arkhipov, Sergey G; Cherkashina, Ksenya A; Kil'met'ev, Alexander S; Boldyreva, Elena V

    2016-12-01

    The pharmaceutical 2:1 co-crystal of meloxicam [MXM; systematic name: 4-hy-droxy-2-methyl-N-(5-methyl-thia-zol-2-yl)-2H-1,2-benzo-thia-zine-3-carboxamide 1,1-dioxide] with acetyl-enedi-carb-oxy-lic acid (ACA; systematic name: but-2-ynedioic acid), crystallizes with one MXM mol-ecule and half an ACA mol-ecule in the asymmetric unit, C14H13N3O4S2·0.5C4H2O4. The mid-point of the triple bond of ACA is located on an inversion centre. In the crystal, the two stereoisomers of MXM with respect to the N atom of the sulfonamide group are related by the inversion centre. The carbonyl and hy-droxy groups belonging to the MXM mol-ecule are involved in an intra-molecular O-H⋯O hydrogen bond. The structure-forming motif includes two MXM mol-ecules linked via an ACA conformer through N-H⋯O and O-H⋯N hydrogen bonds, similar to MXM co-crystals with other di-carb-oxy-lic acids.

  9. Crystal structure of 4-[1-(2-hy-droxy-prop-yl)-4,5-diphenyl-1H-imidazol-2-yl]benzoic acid.

    Science.gov (United States)

    Jasinski, Jerry P; Mohamed, Shaaban K; Akkurt, Mehmet; Abdelhamid, Antar A; Albayati, Mustafa R

    2015-02-01

    In the title compound, C25H22N2O3, the central imidazole ring makes dihedral angles of 48.43 (10), 20.23 (10) and 75.38 (11)° with the benzene ring and the two phenyl rings, respectively. The phenyl ring adjacent to the N-bonded 2-hy-droxy-propyl group shows the greatest twist, presumably to minimize steric inter-actions. In the crystal, mol-ecules are linked by O-H⋯N, O-H⋯O and C-H⋯O hydrogen bonds, forming a three-dimensional network. In addition, C-H⋯π inter-actions are also observed.

  10. Crystal structure of 1,1'-{(pentane-1,5-di-yl)bis[(aza-niumylyl-idene)methanylyl-idene]}bis(naphthalen-2-olate).

    Science.gov (United States)

    Ouari, Kamel; Merzougui, Moufida; Karmazin, Lydia

    2015-09-01

    The whole mol-ecule of the title compound, C27H26N2O2, is generated by twofold rotational symmetry, with the central C atom of the pentyl chain located on the twofold rotation axis. The compound crystallizes as a bis-zwitterion, and there are two intra-molecular N-H⋯O hydrogen bonds generating S(6) ring motifs. In the crystal, mol-ecules are linked by pairs of C-H⋯O hydrogen bonds, forming ribbons propagating along [001], and enclosing R 2 (2)(22) ring motifs.

  11. Crystal structure of 2-amino-4-methyl-pyridin-1-ium (2R,3R)-3-carb-oxy-2,3-di-hydroxy-propano-ate monohydrate.

    Science.gov (United States)

    Jovita, J V; Sathya, S; Usha, G; Vasanthi, R; Ramanand, A

    2014-09-01

    The title mol-ecular salt, C6H9N2 (+)·C4H5O6 (-)·H2O, crystallized with two 2-amino-4-methyl-pyridin-1-ium cations, two l-(+)-tartaric acid monoanions [systematic name: (2R,3R)-3-carb-oxy-2,3-di-hydroxy-propano-ate] and two water mol-ecules in the asymmetric unit. In the crystal, the cations, anions and water mol-ecules are linked via a number of O-H⋯O and N-H⋯O hydrogen bonds, and a C-H⋯O hydrogen bond, forming a three-dimensional structure.

  12. Crystal structure of 2,2-dimethyl-N-(5-methyl-pyridin-2-yl)propanamide.

    Science.gov (United States)

    El-Hiti, Gamal A; Smith, Keith; Hegazy, Amany S; Alanazi, Saud A; Kariuki, Benson M

    2015-06-01

    There are two mol-ecules in the asymmetric unit of the title compound, C11H16N2O. The pyridine rings and amide groups overlap almost perfectly (r.m.s. overlay fit = 0.053 Å), but the tertiary butyl groups have different orientations: in one mol-ecule, one of the methyl C atoms is syn to the amide O atom [O-C-C-C = -0.8 (3)°] and in the other the equivalent torsion angle is 31.0 (2)°. In the crystal, the two independent mol-ecules are linked by a pair of N-H⋯N hydrogen bonds in the form of an R 2 (2)(8) loop to form a dimer. A C-H⋯O inter-action connects the dimers into [100] chains.

  13. Crystal structures of three 3,4,5-tri-meth-oxy-benzamide-based derivatives.

    Science.gov (United States)

    Gomes, Ligia R; Low, John Nicolson; Oliveira, Catarina; Cagide, Fernando; Borges, Fernanda

    2016-05-01

    The crystal structures of three benzamide derivatives, viz. N-(6-hy-droxy-hex-yl)-3,4,5-tri-meth-oxy-benzamide, C16H25NO5, (1), N-(6-anilinohex-yl)-3,4,5-tri-meth-oxy-benzamide, C22H30N2O4, (2), and N-(6,6-di-eth-oxy-hex-yl)-3,4,5-tri-meth-oxy-benzamide, C20H33NO6, (3), are described. These compounds differ only in the substituent at the end of the hexyl chain and the nature of these substituents determines the differences in hydrogen bonding between the mol-ecules. In each mol-ecule, the m-meth-oxy substituents are virtually coplanar with the benzyl ring, while the p-meth-oxy substituent is almost perpendicular. The carbonyl O atom of the amide rotamer is trans related with the amidic H atom. In each structure, the benzamide N-H donor group and O acceptor atoms link the mol-ecules into C(4) chains. In 1, a terminal -OH group links the mol-ecules into a C(3) chain and the combined effect of the C(4) and C(3) chains is a ribbon made up of screw related R 2 (2)(17) rings in which the ⋯O-H⋯ chain lies in the centre of the ribbon and the tri-meth-oxy-benzyl groups forms the edges. In 2, the combination of the benzamide C(4) chain and the hydrogen bond formed by the terminal N-H group to an O atom of the 4-meth-oxy group link the mol-ecules into a chain of R 2 (2)(17) rings. In 3, the mol-ecules are linked only by C(4) chains.

  14. Crystal structures of (2E)-1-(3-bromo-thio-phen-2-yl)-3-(2-meth-oxy-phen-yl)prop-2-en-1-one and (2E)-1-(3-bromo-thio-phen-2-yl)-3-(3,4-di-meth-oxy-phen-yl)prop-2-en-1-one.

    Science.gov (United States)

    Naik, Vasant S; Shettigar, Venkataraya; Berglin, Tyler S; Coburn, Jillian S; Jasinski, Jerry P; Yathirajan, Hemmige S

    2015-08-01

    In the mol-ecules of the title compounds, (2E)-1-(3-bromo-thio-phen-2-yl)-3-(2-meth-oxy-phen-yl)prop-2-en-1-one, C14H11BrO2S, (I), which crystallizes in the space group P-1 with four independent mol-ecules in the asymmetric unit (Z' = 8), and (2E)-1-(3-bromo-thio-phen-2-yl)-3-(3,4-di-meth-oxy-phen-yl)prop-2-en-1-one, C15H13BrO3S, (II), which crystallizes with Z' = 8 in the space group I2/a, the non-H atoms are nearly coplanar. The mol-ecules of (I) pack with inversion symmetry stacked diagonally along the a-axis direction. Weak C-H⋯Br intra-molecular inter-actions in each of the four mol-ecules in the asymmetric unit are observed. In (II), weak C-H⋯O, bifurcated three-center inter-molecular inter-actions forming dimers along with weak C-H⋯π and π-π stacking inter-actions are observed, linking the mol-ecules into sheets along [001]. A weak C-H⋯Br intra-molecular inter-action is also present. There are no classical hydrogen bonds present in either structure.

  15. Crystal structure of 4-(3-carb-oxy-pro-pan-amido)-2-hy-droxy-benzoic acid mono-hydrate.

    Science.gov (United States)

    Tahir, Muhammad Nawaz; Ahmed, Muhammad Naeem; Butt, Arshad Farooq; Shad, Hazoor Ahmad

    2014-12-01

    In the title hydrate, C11H11NO6·H2O, the organic mol-ecule is approximately planar (r.m.s. deviation for the non-H atoms = 0.129 Å) and an intra-molecular O-H⋯O hydrogen bond closes an S(6) ring. In the crystal, the benzoic acid group participates in an O-H⋯O hydrogen bond to the water mol-ecule and accepts a similar bond from another water mol-ecule. The other -CO2H group forms a carb-oxy-lic acid inversion dimer, thereby forming an R 2 (2)(8) loop. These bonds, along with N-H⋯O and C-H⋯O inter-actions, generate a three-dimensional network.

  16. Crystal structures of N(2),N(3),N(5),N(6)-tetra-kis-(pyridin-2-ylmeth-yl)pyrazine-2,3,5,6-tetra-carboxamide and N(2),N(3),N(5),N(6)-tetra-kis-(pyridin-4-ylmeth-yl)pyrazine-2,3,5,6-tetra-carboxamide.

    Science.gov (United States)

    Cati, Dilovan S; Stoeckli-Evans, Helen

    2017-02-01

    The title compounds, C32H28N10O4· unknown solvent, (I), and C32H28N10O4, (II), are pyrazine-2,3,5,6-tetra-carboxamide derivatives. In (I), the substituents are (pyridin-2-ylmeth-yl)carboxamide, while in (II), the substituents are (pyridin-4-ylmeth-yl)carboxamide. Both compounds crystallize in the monoclinic space group P21/n, with Z' = 1 for (I), and Z' = 0.5 for (II). The whole mol-ecule of (II) is generated by inversion symmetry, the pyrazine ring being situated about a center of inversion. In (I), the four pyridine rings are inclined to the pyrazine ring by 83.9 (2), 82.16 (18), 82.73 (19) and 17.65 (19)°. This last dihedral angle involves a pyridine ring that is linked to the adjacent carboxamide O atom by an intra-molecular C-H⋯O hydrogen bond. In compound (II), the unique pyridine rings are inclined to the pyrazine ring by 33.3 (3) and 81.71 (10)°. There are two symmetrical intra-molecular C-H⋯O hydrogen bonds present in (II). In the crystal of (I), mol-ecules are linked by N-H⋯O and N-H⋯N hydrogen bonds, forming layers parallel to (10-1). The layers are linked by C-H⋯O and C-H⋯N hydrogen bonds, forming a three-dimensional framework. In the crystal of (II), mol-ecules are linked by N-H⋯N hydrogen bonds, forming chains propagating along the [010] direction. The chains are linked by a weaker N-H⋯N hydrogen bond, forming layers parallel to the (101) plane, which are in turn linked by C-H⋯O hydrogen bonds, forming a three-dimensional structure. In the crystal of compound (I), a region of disordered electron density was treated with the SQUEEZE routine in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9-18]. Their contribution was not taken into account during refinement. In compound (II), one of the pyridine rings is positionally disordered, and the refined occupancy ratio for the disordered Car-Car-Npy atoms is 0.58 (3):0.42 (3).

  17. Crystal structure and Hirshfeld surface analysis of 1-carb-oxy-2-(3,4-di-hydroxy-phen-yl)ethan-1-aminium bromide 2-ammonio-3-(3,4-di-hydroxy-phen-yl)propano-ate.

    Science.gov (United States)

    Kathiravan, Perumal; Balakrishnan, Thangavelu; Venkatesan, Perumal; Ramamurthi, Kandasamy; Percino, María Judith; Thamotharan, Subbiah

    2016-11-01

    In the title mol-ecular salt, C9H12NO4(+)·Br(-)·C9H11NO4, one of the dopa mol-ecules is in the cationic form in which the α-amino group is protonated and the α-carb-oxy-lic acid group is uncharged, while the second dopa mol-ecule is in the zwitterion form. The Br(-) anion occupies a special position and is located on a twofold rotation axis. The two dopa mol-ecules are inter-connected by short O-H⋯O hydrogen bonds. In the crystal, the various units are linked by O-H⋯O, N-H⋯Br and N-H⋯O hydrogen bonds, forming a three-dimensional framework. The title compound was refined as an inversion twin with an absolute structure parameter of 0.023 (8).

  18. Crystal structure of 6-amino-4-(3-bromo-4-meth-oxy-phen-yl)-3-methyl-2,4-di-hydro-pyrano[2,3-c]pyrazole-5-carbo-nitrile dimethyl sulfoxide monosolvate.

    Science.gov (United States)

    Yousuf, Sammer; Bano, Huma; Muhammad, Munira Taj; Khan, Khalid Mohammed

    2015-07-01

    In the pyrazole mol-ecule of the title solvate, C15H13BrN4O2·C2H6OS, the dihedral angle between the benzene ring and the mean plane of the di-hydro-pyrano[2,3-c]pyrazole ring system [r.m.s deviation = 0.031 (2) Å] is 86.71 (14)°. In the crystal, the pyrazole mol-ecules are linked by N-H⋯N hydrogen bonds, forming a layer parallel to (10-1). The pyrazole and dimethyl sulfoxide mol-ecules are connected by an N-H⋯O hydrogen bond.

  19. Crystal structure of tris[(4,7,13,16,21,24-hexa-oxa-1,10-di-aza-bicyclo-[8.8.8]hexa-cosane-κ(8)N2,O6)rubidium] rubidium nona-stannide.

    Science.gov (United States)

    Klein, Wilhelm; He, Haiyan; Fässler, Thomas F

    2017-02-01

    The crystal structure of the title compound, [Rb(C18H36N2O6)]3RbSn9, consists of deltahedral [Sn9](4-) cluster anions, Rb(+) cations and cryptand mol-ecules, which partially sequester the cations. Those cations, which are not coordinated by cryptand mol-ecules, are neighboured directly to the [Sn9](4-) clusters and inter-connect them to form ∞(1)[RbSn9](3-) chains. These chains extend parallel to [001] and are arranged in a pseudo-hexa-gonal rod packing, separated by the Rb-cryptand complex cations.

  20. Supra-molecular inter-actions in the 1:2 co-crystal of 4,4'-bipyridine and 3-chloro-thio-phene-2-carb-oxy-lic acid.

    Science.gov (United States)

    Prajina, Olakkandiyil; Thomas Muthiah, Packianathan; Geiger, David K

    2016-10-01

    The asymmetric unit of the title compound, 2C5H3ClO2S·C10H8N2, is comprised of a mol-ecule of 3-chloro-thio-phene-2-carb-oxy-lic acid (3TPC) and half of a mol-ecule of 4,4'-bi-pyridine (BPY). A distinctive O-H⋯N-based synthon is present. Cl⋯Cl and π-π stacking inter-actions further stabilize the crystal structure, forming a two-dimensional network parallel to the bc plane.

  1. Crystal structure of glycidamide: the mutagenic and genotoxic metabolite of acryl-amide.

    Science.gov (United States)

    Hemgesberg, Melanie N; Bonck, Thorsten; Merz, Karl-Heinz; Sun, Yu; Schrenk, Dieter

    2016-08-01

    The title compound, glycidamide (systematic name: oxirane-2-carboxamide), C3H5NO2, is the mutagenic and genotoxic metabolite of acryl-amide, a food contaminant and industrial chemical that has been classified as being probably carcinogenic to humans. Synthesized via the reaction of acrylo-nitrile and hydrogen peroxide, it crystallizes with both enanti-omers occurring as two crystallographically independent mol-ecules (A and B) in the asymmetric unit. They have similar conformations with an r.m.s. deviation of 0.0809 Å for mol-ecule B inverted on mol-ecule A. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, which lead to the formation of β-sheet structures enclosing R 2 (2)(8) and R 4 (2)(8) loops. The β-sheets are linked by weaker C-H⋯O hydrogen bonds, forming a supra-molecular three-dimensional structure.

  2. Crystal structure of 7,7-dimethyl-6-methyl-idenetri-cyclo-[6.2.1.0(1,5)]undecane-2-carb-oxy-lic acid.

    Science.gov (United States)

    Beghidja, Noureddine; Benayache, Samir; Benayache, Fadila; Knight, David W; Kariuki, Benson M

    2015-02-01

    In the title compound, C15H22O2, both five-membered rings display an envelope conformation whereas the six-membered ring displays a chair conformation. In the crystal, pairs of O-H⋯O hydrogen bonds between carb-oxy-lic groups link mol-ecules, related by a twofold rotation axis, into supra-molecular dimers.

  3. Crystal structures of (Z)-5-[2-(benzo[b]thio-phen-2-yl)-1-(3,5-di-meth-oxy-phen-yl)ethen-yl]-1H-tetra-zole and (Z)-5-[2-(benzo[b]thio-phen-3-yl)-1-(3,4,5-tri-meth-oxy-phen-yl)ethen-yl]-1H-tetra-zole.

    Science.gov (United States)

    Penthala, Narsimha Reddy; Yadlapalli, Jaishankar K B; Parkin, Sean; Crooks, Peter A

    2016-05-01

    (Z)-5-[2-(Benzo[b]thio-phen-2-yl)-1-(3,5-di-meth-oxy-phen-yl)ethen-yl]-1H-tetrazole methanol monosolvate, C19H16N4O2S·CH3OH, (I), was prepared by the reaction of (Z)-3-(benzo[b]thio-phen-2-yl)-2-(3,5-di-meth-oxy-phen-yl)acrylo-nitrile with tri-butyl-tin azide via a [3 + 2]cyclo-addition azide condensation reaction. The structurally related compound (Z)-5-[2-(benzo[b]thio-phen-3-yl)-1-(3,4,5-tri-meth-oxy-phen-yl)ethen-yl]-1H-tetra-zole, C20H18N4O3S, (II), was prepared by the reaction of (Z)-3-(benzo[b]thio-phen-3-yl)-2-(3,4,5-tri-meth-oxy-phen-yl)acrylo-nitrile with tri-butyl-tin azide. Crystals of (I) have two mol-ecules in the asymmetric unit (Z' = 2), whereas crystals of (II) have Z' = 1. The benzo-thio-phene rings in (I) and (II) are almost planar, with r.m.s deviations from the mean plane of 0.0084 and 0.0037 Å in (I) and 0.0084 Å in (II). The tetra-zole rings of (I) and (II) make dihedral angles with the mean planes of the benzo-thio-phene rings of 88.81 (13) and 88.92 (13)° in (I), and 60.94 (6)° in (II). The di-meth-oxy-phenyl and tri-meth-oxy-phenyl rings make dihedral angles with the benzo-thio-phene rings of 23.91 (8) and 24.99 (8)° in (I) and 84.47 (3)° in (II). In both structures, mol-ecules are linked into hydrogen-bonded chains. In (I), these chains involve both tetra-zole and methanol, and are parallel to the b axis. In (II), mol-ecules are linked into chains parallel to the a axis by N-H⋯N hydrogen bonds between adjacent tetra-zole rings.

  4. Mol-ecular and crystal structure of gossypol tetra-methyl ether with an unknown solvate.

    Science.gov (United States)

    Honkeldieva, Muhabbat; Talipov, Samat; Mardanov, Rustam; Ibragimov, Bakhtiyar

    2015-02-01

    The title compound, C34H38O8 (systematic name: 5,5'-diisopropyl-2,2',3,3'-tetra-meth-oxy-7,7'-dimethyl-2H,2'H-8,8'-bi-[naphtho-[1,8-bc]furan]-4,4'-diol), has been obtained from a gossypol solution in a mixture of dimethyl sulfate and methanol. The mol-ecule is situated on a twofold rotation axis, so the asymmetric unit contains one half-mol-ecule. In the mol-ecule, the hy-droxy groups are involved in intra-molecular O-H⋯O hydrogen bonds, and the two naphthyl fragments are inclined each to other by 83.8 (1)°. In the crystal, weak C-H⋯O and C-H⋯π inter-actions consolidate the packing, which exhibits channels with an approximate diameter of 6 Å extending along the c-axis direction. These channels are filled with highly disordered solvent mol-ecules, so their estimated scattering contribution was subtracted from the observed diffraction data using the SQUEEZE option in PLATON [Spek, A. L. (2015). Acta Cryst. C71, 9-18].

  5. Crystal structures of hydrogen-bonded co-crystals as liquid crystal precursors: 4-(n-pent-yloxy)benzoic acid-(E)-1,2-bis-(pyridin-4-yl)ethene (2/1) and 4-(n-hex-yloxy)benzoic acid-(E)-1,2-bis-(pyridin-4-yl)ethene (2/1).

    Science.gov (United States)

    Tabuchi, Yohei; Gotoh, Kazuma; Ishida, Hiroyuki

    2016-12-01

    The crystal structures of title hydrogen-bonded co-crystals, 2C12H16O3·C12H10N2, (I), and 2C13H18O3·C12H10N2, (II), have been determined at 93 K. In (I), the asymmetric unit consists of one 4-(n-pent-yloxy)benzoic acid mol-ecule and one half-mol-ecule of (E)-1,2-bis-(pyridin-4-yl)ethene, which lies about an inversion centre. The asymmetric unit of (II) comprises two crystallographically independent 4-(n-hex-yloxy)benzoic acid mol-ecules and one 1,2-bis-(pyridin-4-yl)ethene mol-ecule. In each crystal, the acid and base components are linked by O-H⋯N hydrogen bonds, forming a linear hydrogen-bonded 2:1 unit of the acid and the base. The 2:1 units are linked via C-H⋯π and π-π inter-actions [centroid-centroid distances of 3.661 (2) and 3.909 (2) Å for (I), and 3.546 (2)-3.725 (4) Å for (II)], forming column structures. In (II), the base mol-ecule is orientationally disordered over two sets of sites approximately around the N⋯N mol-ecular axis, with an occupancy ratio of 0.647 (4):0.353 (4), and the average structure of the 2:1 unit adopts nearly pseudo-C2 symmetry. Both compounds show liquid-crystal behaviour.

  6. Crystallization of accessory phases in magmas by local saturation adjacent to phenocrysts

    Science.gov (United States)

    Bacon, C.R.

    1989-01-01

    Accessory minerals commonly occur attached to or included in the major crystalline phases of felsic and some intermediate igneous rocks. Apatite is particularly common as inclusions, but Fe-Ti oxides, pyrrhotite, zircon, monazite, chevkinite and xenotime are also known from silicic rocks. Accessories may nucleate near the host crystal/ liquid interface as a result of local saturation owing to formation of a differentiated chemical boundary layer in which accessory mineral solubility would be lower than in the surrounding liquid. Differentiation of this boundary layer would be greatest adjacent to ferromagnesian phenocrysts, especially Fe-Ti oxides; it is with oxides that accessories are most commonly associated in rocks. A boundary layer may develop if the crystal grows more rapidly than diffusion can transport incorporated and rejected elements to and from the phenocryst. Diffusion must dominate over convection as a mode of mass transfer near the advancing crystal/liquid interface in order for a boundary layer to exist. Accumulation of essential structural constituent elements of accessory minerals owing to their slow diffusion in evolved silicate melt also may force local saturation, but this is not a process that applies to all cases. Local saturation is an attractive mechanism for enhancing fractionation during crystallization differentiation. If accessory minerals attached to or included in phenocrysts formed because of local saturation, their host phenocrysts must have grown rapidly when accessories nucleated in comparison to lifetimes of magma reservoirs. Some inconsistencies remain in a local saturation origin for accessory phases that cannot be evaluated without additional information. ?? 1989.

  7. Crystal structure of catena-poly[[(dimethyl sulfoxide-κO)(pyridine-2,6-di-carboxyl-ato-κ(3) O,N,O')nickel(II)]-μ-pyrazine-κ(2) N:N'].

    Science.gov (United States)

    Liu, Chen; Thuijs, Annaliese E; Felts, Ashley C; Ballouk, Hamza F; Abboud, Khalil A

    2016-05-01

    The title coordination polymer, [Ni(C7H3NO4)(C4H4N2)(C2H6OS)] n , consists of [010] chains composed of Ni(II) ions linked by bis-monodentate-bridging pyrazine mol-ecules. Each of the two crystallographically distinct Ni(II) ions is located on a mirror plane and is additionally coordinated by a dimethyl sulfoxide (DMSO) ligand through the oxygen atom and by a tridentate 2,6-pyridine-di-carb-oxy-lic acid dianion through one of each of the carboxyl-ate oxygen atoms and the pyridine nitro-gen atom, leading to a distorted octa-hedral coordination environment. The title structure exhibits an inter-esting complementarity between coordinative bonding and π-π stacking where the Ni-Ni distance of 7.0296 (4) Å across bridging pyrazine ligands allows the pyridine moieties on two adjacent chains to inter-digitate at halfway of the Ni-Ni distance, resulting in π-π stacking between pyridine moieties with a centroid-to-plane distance of 3.5148 (2) Å. The double-chain thus formed also exhibits C-H⋯π inter-actions between pyridine C-H groups on one chain and pyrazine mol-ecules on the other chain. As a result, the inter-ior of the double-chain structure is dominated by π-π stacking and C-H⋯ π inter-actions, while the space between the double-chains is occupied by a C-H⋯O hydrogen-bonding network involving DMSO ligands and carboxyl-ate groups located on the exterior of the double-chains. This separation of dissimilar inter-actions in the inter-ior and exterior of the double-chains further stabilizes the crystal structure.

  8. Crystal structure of N,N,N',N',N'',N''-hexa-methyl-guanidinium cyanate 1.5-hydrate.

    Science.gov (United States)

    Tiritiris, Ioannis; Kantlehner, Willi

    2015-12-01

    The title hydrated salt, C7H18N3 (+)·OCN(-).1.5H2O, was synthesized starting from N,N,N',N',N'',N''-hexa-methyl-guanidinium chloride by a twofold anion-exchange reaction. The asymmetric unit contains two cations, two cyanate anions and three water mol-ecules. One cation shows orientational disorder and two sets of N-atom positions were found related by a 60° rotation, with an occupancy ratio of 0.852 (6):0.148 (6). The C-N bond lengths in both guanidin-ium ions range from 1.329 (2) to 1.358 (10) Å, indicating double-bond character, pointing towards charge delocalization within the NCN planes. Strong O-H⋯N hydrogen bonds between the crystal water mol-ecules and the cyanate ions and strong O-H⋯O hydrogen bonds between the water mol-ecules are present, resulting in a two-dimensional hydrogen bonded network running parallel to the (001) plane. The hexa-methyl-guanidinium ions are packed in between the layers built up by water mol-ecules and cyanate ions.

  9. Two tautomers in the same crystal: 3-(4-fluoro-phen-yl)-1H-pyrazole and 5-(4-fluoro-phen-yl)-1H-pyrazole.

    Science.gov (United States)

    Yamuna, Thammarse S; Kaur, Manpreet; Jasinski, Jerry P; Anderson, Brian J; Yathirajan, H S

    2014-09-01

    The title co-crystal, 3-(4-fluoro-phen-yl)-1H-pyrazole-5-(4-fluoro-phen-yl)-1H-pyrazole (1/1), C9H7FN2, crystallizes with four independent mol-ecules (A, B, C and D) in the asymmetric unit exhibiting two tautomeric forms (A and D; B and C) due to N-H proton exchange between the two N atoms of the pyrazole ring. The dihedral angles between the mean planes of the pyrazole and benzene rings are 15.6 (1), 19.8 (9), 14.0 (1) and 10.7 (7)° in mol-ecules A, B, C and D, respectively. In the crystal, N-H⋯N hydrogen bonds link the four mol-ecules in the asymmetric unit into a ring with an R 4 (4)(12) motif. Furthermore, weak C-H⋯F inter-actions link the mol-ecules into a three-dimensional network.

  10. Crystal structures of 3-fluoro-N-[2-(tri-fluoro-meth-yl)phen-yl]benzamide, 3-bromo-N-[2-(tri-fluoro-meth-yl)phen-yl]benzamide and 3-iodo-N-[2-(tri-fluoro-meth-yl)phen-yl]benzamide.

    Science.gov (United States)

    Suchetan, P A; Suresha, E; Naveen, S; Lokanath, N K

    2016-06-01

    In the title compounds, C14H9F4NO, (I), C14H9BrF3NO, (II), and C14H9F3INO, (III), the two benzene rings are inclined to one another by 43.94 (8)° in mol-ecule A and 55.66 (7)° in mol-ecule B of compound (I), which crystallizes with two independent mol-ecules in the asymmetric unit, but by only 10.40 (12)° in compound (II) and 12.5 (2)° in compound (III). In the crystals of all three compounds, N-H⋯O hydrogen bonds link the mol-ecules to form chains propagating along the a-axis direction for (I), and along the b-axis direction for (II) and (III). In the crystal of (I), -A-B-A-B- chains are linked by C-H⋯O hydrogen bonds, forming layers parallel to (010). Within the layers there are weak offset π-π inter-actions present [inter-centroid distances = 3.868 (1) and 3.855 (1) Å]. In the crystals of (II) and (III), the chains are linked via short halogen-halogen contacts [Br⋯Br = 3.6141 (4) Å in (II) and I⋯I = 3.7797 (5) Å in (III)], resulting in the formation of ribbons propagating along the b-axis direction.

  11. Crystal structure of [1,1':3',1''-ter-phenyl]-2',3,3''-tri-carb-oxy-lic acid.

    Science.gov (United States)

    Decato, Daniel A; Berryman, Orion B

    2015-09-01

    The asymmetric unit of the title compound, C21H14O6, com-prises two symmetrically independent mol-ecules that form a locally centrosymmetric hydrogen-bonded dimer, with the planes of the corresponding carb-oxy-lic acid groups rotated by 15.8 (1) and 17.5 (1)° relative to those of the adjacent benzene rings. The crystal as a whole, however, exhibits a noncentrosymmetric packing, described by the polar space group Pca21. The dimers form layers along the ab plane, being inter-connected by hydrogen bonds involving the remaining carb-oxy-lic acid groups. The plane of the central carb-oxy-lic acid group forms dihedral angles of 62.5 (1) and 63.0 (1)° with those of the adjacent benzene rings and functions as a hydrogen-bond donor and acceptor. As a donor, it inter-connects adjacent layers, while as an acceptor it stabilizes the packing within the layers. The 'distal' carb-oxy-lic acid groups are nearly coplanar with the planes of the adjacent benzene rings, forming dihedral angles of 1.8 (1) and 7.1 (1)°. These groups also form intra- and inter-layer hydrogen bonds, but with 'reversed' functionality, as compared with the central carb-oxy-lic acid groups.

  12. Crystal structure of N-(tert-but-oxy-carbon-yl)phenyl-alanylde-hydro-alanine isopropyl ester (Boc-Phe-ΔAla-OiPr).

    Science.gov (United States)

    Lenartowicz, Paweł; Makowski, Maciej; Zarychta, Bartosz; Ejsmont, Krzysztof

    2014-12-01

    In the title compound, the de-hydro-dipeptide (Boc-Phe-ΔAla-OiPr, C20H28N2O5), the mol-ecule has a trans conformation of the N-methyl-amide group. The geometry of the de-hydro-alanine moiety is to some extent different from those usually found in simple peptides, indicating conjugation between the H2C=C group and the peptide bond. The bond angles around de-hydro-alanine have unusually high values due to the steric hindrance, the same inter-action influencing the slight distortion from planarity of the de-hydro-alanine. The mol-ecule is stabilized by intra-molecular inter-actions between the isopropyl group and the N atoms of the peptide main chain. In the crystal, an N-H⋯O hydrogen bond links the mol-ecules into ribbons, giving a herringbone head-to-head packing arrangement extending along the [100] direction. In the stacks, the mol-ecules are linked by weak C-H⋯O hydrogen-bonding associations.

  13. Crystal structures of 2-[(4,6-di-amino-pyrimidin-2-yl)sulfan-yl]-N-(3-nitro-phen-yl)acetamide monohydrate and N-(2-chloro-phen-yl)-2-[(4,6-di-amino-pyrimidin-2-yl)sulfan-yl]acetamide.

    Science.gov (United States)

    Subasri, S; Timiri, Ajay Kumar; Barji, Nayan Sinha; Jayaprakash, Venkatesan; Vijayan, Viswanathan; Velmurugan, Devadasan

    2016-08-01

    The title compounds, C12H12N6O3S·H2O, (I), and C12H12ClN5OS, (II), are 2-[(4,6-di-amino-pyrimidin-2-yl)sulfan-yl]acetamides. Compound (I) crystallized as a monohydrate. In both compounds, the mol-ecules have a folded conformation, with the pyrimidine ring being inclined to the benzene ring by 56.18 (6)° in (I) and by 67.84 (6)° in (II). In both mol-ecules, there is an intra-molecular N-H⋯N hydrogen bond stabilizing the folded conformation. In (I), there is also a C-H⋯O intra-molecular short contact, and in (II) an intra-molecular N-H⋯Cl hydrogen bond is present. In the crystal of (I), mol-ecules are linked by a series of N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonds, forming undulating sheets parallel to the (100). The sheets are linked via an N-H⋯Owater hydrogen bond, forming a three-dimensional network. In the crystal of (II), mol-ecules are linked by a series of N-H⋯O, N-H⋯N and C-H⋯O hydrogen bonds, forming slabs parallel to (001).

  14. Crystal structure of cis-diamminebis(nitrito-κN)platinum(II).

    Science.gov (United States)

    Kahlenberg, Volker; Gelbrich, Thomas; Tessadri, Richard; Klauser, Frederik

    2015-04-01

    Single crystals of cis-[Pt(NO2)2(NH3)2], were obtained by means of hyper-saturation directly out of a plating electrolyte. The square-planar coordination environment of the divalent Pt(II) atom is formed by four N atoms belonging to two ammine and two monodentate nitrite ligands. The ligands adopt a cis configuration. The crystal structure contains stacks of close-packed mol-ecules which run parallel to [001]. There are nine crystallographically independent inter-molecular N-H⋯O hydrogen bonds, resulting in a hydrogen-bonded hxl-type framework in which each mol-ecule serves as an eight-connected node. Four of the nine distinct hydrogen bonds connect complexes which belong to the same close-packed column parallel to [001]. In contrast to the previously reported crystal structure of the trans isomer, the title structure does not display intra-molecular hydrogen bonding.

  15. Crystal and mol-ecular structure of aflatrem.

    Science.gov (United States)

    Lenta, Bruno N; Ngatchou, Jules; Kenfack, Patrice T; Neumann, Beate; Stammler, Hans-Georg; Sewald, Norbert

    2015-11-01

    The crystal structure of the title compound, C32H39NO4, confirms the absolute configuration of the seven chiral centres in the mol-ecule. The molecule has a 1,1-dimethylprop-2-enyl substituent on the indole nucleus and this nucleus shares one edge with the five-membered ring which is, in turn, connected to a sequence of three edge-shared fused rings. The skeleton is completed by the 7,7-trimethyl-6,8-dioxabi-cyclo-[3.2.1]oct-3-en-2-one group connected to the terminal cyclohexene ring. The two cyclohexane rings adopt chair and half-chair conformations, while in the dioxabi-cyclo-[3.2.1]oct-3-en-2-one unit, the six-membered ring has a half-chair conformation. The indole system of the mol-ecule exhibits a tilt of 2.02 (1)° between its two rings. In the crystal, O-H⋯O hydrogen bonds connect mol-ecules into chains along [010]. Weak N-H⋯π inter-actions connect these chains, forming sheets parallel to (10-1).

  16. Crystal structure of 3,4-di-meth-oxy-phenol.

    Science.gov (United States)

    Mills-Robles, Heather A; Desikan, Vasumathi; Golen, James A; Manke, David R

    2015-12-01

    The title compound, C8H10O3, has two planar mol-ecules in the asymmetric unit possessing mean deviations from planarity of 0.051 and 0.071 Å. In the crystal, there are two distinct infinite chains, both along [010]. The chains are formed by O-H⋯O inter-actions between the phenol and both the 3-meth-oxy and the 4-meth-oxy groups.

  17. Crystal structures of 4-meth-oxy-benzoic acid-1,3-bis-(pyridin-4-yl)propane (2/1) and biphenyl-4,4'-di-carb-oxy-lic acid-4-meth-oxy-pyridine (1/2).

    Science.gov (United States)

    Gotoh, Kazuma; Ishida, Hiroyuki

    2017-07-01

    The crystal structures of two hydrogen-bonded compounds, namely 4-meth-oxy-benzoic acid-1,3-bis-(pyridin-4-yl)propane (2/1), C13H14.59N2·C8H7.67O3·C8H7.74O3, (I), and biphenyl-4,4'-di-carb-oxy-lic acid-4-meth-oxy-pyridine (1/2), C14H9.43O4·C6H7.32NO·C6H7.25NO, (II), have been determined at 93 K. In (I), the asymmetric unit consists of two crystallographically independent 4-meth-oxy-benzoic acid mol-ecules and one 1,3-bis-(pyridin-4-yl)propane mol-ecule. The asymmetric unit of (II) comprises one biphenyl-4,4'-di-carb-oxy-lic acid mol-ecule and two independent 4-meth-oxy-pyridine mol-ecules. In each crystal, the acid and base mol-ecules are linked by short O-H⋯N/N-H⋯O hydrogen bonds, in which H atoms are disordered over the acid O-atom and base N-atom sites, forming a linear hydrogen-bonded 2:1 or 1:2 unit of the acid and the base. The 2:1 units of (I) are linked via C-H⋯π, π-π and C-H⋯O inter-actions into a tape structure along [101], while the 1:2 units of (II) form a double-chain structure along [-101] through π-π and C-H⋯O inter-actions.

  18. Crystal structure of 2-[(di-chloro-methane)sulfon-yl]pyridine.

    Science.gov (United States)

    Chen, Zhiqiu; Bolat, Hembat; Wan, Xing; Li, Ya

    2014-12-01

    The asymmetric unit of the title compound, C6H5Cl2NO2S, contains two mol-ecules with similar conformations (r.m.s. overlay fit for the non-H atoms = 0.067 Å). Atoms attached to the pendent Csp (3)-S bond are arranged in a staggered conformation with one of the Cl atoms anti to the C atom in the aromatic ring [C-S-C-Cl torsion angles = 178.41 (11) and -176.70 (13)°]. In the crystal, mol-ecules are linked by C-H⋯N and C-H⋯O hydrogen bonds, generating a three-dimensional network, and weak aromatic π-π stacking is also observed [centroid-centroid separation = 3.8902 (17) Å].

  19. 4,4'-Dimeth-oxybi-phenyl-3,3'-di-car-box-ylic acid.

    Science.gov (United States)

    Lundvall, Fredrik; Wragg, David Stephen; Dietzel, Pascal D C; Fjellvåg, Helmer

    2014-05-01

    The title compound, C16H14O6, was recrystallized under solvothermal conditions. The mol-ecules are located on inversion centres, with one complete mol-ecule generated from the asymmetric unit by inversion. There are intra-molecular O-H⋯O hydrogen bonds involving the carb-oxy-lic acid group and the O atom of the adjacent meth-oxy group. In the crystal, mol-ecules are linked via O-H⋯O hydrogen bonds, forming chains propagating along [100]. The chains are linked via C-H⋯O hydrogen bonds, forming sheets parallel to (001).

  20. Selective crystallization of indigo B by a modified sublimation method and its redetermined structure.

    Science.gov (United States)

    Kettner, Florian; Hüter, Lucie; Schäfer, Johanna; Röder, Konstantin; Purgahn, Uta; Krautscheid, Harald

    2011-11-01

    Good-quality single crystals of the title compound, indigo B [systematic name: 2-(3-oxoindolin-2-yl-idene)indolin-3-one], C(16)H(10)N(2)O(2), have been prepared with high selectivity by a sublimation process. The previous structure of indigo B [Süsse & Wolf (1980 ▶). Naturwissenschaften, 67, 453], which showed that the complete mol-ecule is generated by crystallographic inversion symmetry has been confirmed, but the present study reports more realistic geometrical parameters and modern standards of precision (e.g. σ for C-C bonds = 0.002-0.003 Å). Each mol-ecule features two intra-molecular N-H⋯O hydrogen bonds. In the crystal, mol-ecules are linked by strong face-to-face π-π stacking inter-actions involving both the six- and five-membered rings [centroid-centroid separations = 3.6290 (14) and 3.6506 (14) Å] and inter-molecular N-H⋯O hydrogen bonds.

  1. Crystal structures of two nickel compounds comprising neutral Ni(II) hydrazone complexes and di-carb-oxy-lic acids.

    Science.gov (United States)

    Nakanishi, Takumi; Sato, Osamu

    2017-02-01

    Two isostructural Ni(II) compounds, bis-{N-[1-(pyridin-2-yl-κN)eth-ylidene]pyridine-4-carbohydrazonato-κ(2)N',O}nickel(II)-2,5-di-chloro-terephthalic acid (1/1), [Ni(C13H11N4O)2](C8H4Cl2O4), and bis-{N-[1-(pyridin-2-yl-κN)eth-ylidene]pyridine-4-carbohydrazonato-κ(2)N',O}nickel(II)-2,5-di-bromo-terephthalic acid (1/1), [Ni(C13H11N4O)2](C8H4Br2O4), were synthesized and their crystal structures determined. The pair of N,N',O-tridentate N-[1-(pyridin-2-yl-κN)eth-yl]pyridine-4-carbohydrazonate L ligands result in a cis-NiO2N4 octa-hedral coordination sphere for the metal ions. The asymmetric units consist of two half-mol-ecules of the di-carb-oxy-lic acids, which are completed by crystallographic inversion symmetry. In the respective crystals, the 2,5-di-chloro-terephthalic acid (H2Cl2TPA, 1-Cl) mol-ecules form zigzag hydrogen-bonded chains with the [Ni(L)2] mol-ecules, with the hydrogen-bond distances in 1-Br slightly longer than those in 1-Cl. The packing is consolidated by aromatic π-π stacking between the di-carb-oxy-lic acid mol-ecules and terminal pyridine rings in [Ni(L)2] and short halogen-halogen inter-actions are also observed. The qualitative prediction of the H-atom position from the C-N-C angles of the terminal pyridine rings in L and the C-O distances in the carboxyl groups show that 1-Cl and 1-Br are co-crystals rather than salts.

  2. Crystal structures of four co-crystals of (E)-1,2-di(pyridin-4-yl)ethene with 4-alk-oxy-benzoic acids: 4-meth-oxy-benzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1), 4-eth-oxy-benzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1), 4-n-propoxybenzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1) and 4-n-but-oxy-benzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1).

    Science.gov (United States)

    Tabuchi, Yohei; Gotoh, Kazuma; Ishida, Hiroyuki

    2016-11-01

    The crystal structures of four hydrogen-bonded co-crystals of 4-alk-oxy-benzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1), namely, 2C8H8O3·C12H10N2, (I), 2C9H10O3·C12H10N2, (II), 2C10H12O3·C12H10N2, (III) and 2C11H14O3·C12H10N2, (IV), have been determined at 93 K. In compounds (I) and (IV), the asymmetric units are each composed of one 4-alk-oxy-benzoic acid mol-ecule and one half-mol-ecule of (E)-1,2-di(pyridin-4-yl)ethene, which lies on an inversion centre. The asymmetric unit of (II) consists of two crystallographically independent 4-eth-oxy-benzoic acid mol-ecules and one 1,2-di(pyridin-4-yl)ethene mol-ecule. Compound (III) crystallizes in a non-centrosymmetric space group (Pc) and the asymmetric unit comprises four 4-n-propoxybenzoic acid mol-ecules and two (E)-1,2-di(pyridin-4-yl)ethane mol-ecules. In each crystal, the acid and base components are linked by O-H⋯N hydrogen bonds, forming a linear hydrogen-bonded 2:1 unit of the acid and the base. In (I), (II) and (III), inter-molecular C-H⋯O inter-actions are observed. The 2:1 units of (I) and (II) are linked via C-H⋯O hydrogen bonds, forming tape structures. In (III), the C-H⋯O hydrogen bonds, except for those formed in the units, link the two crystallographically independent 2:1 units. In (IV), no C-H⋯O inter-actions are observed, but π-π and C-H⋯π inter-actions link the units into a column structure.

  3. Comparison of the crystal structures of methyl 4-bromo-2-(meth-oxy-meth-oxy)benzoate and 4-bromo-3-(meth-oxy-meth-oxy)benzoic acid.

    Science.gov (United States)

    Suchetan, P A; Suneetha, V; Naveen, S; Lokanath, N K; Krishna Murthy, P

    2016-04-01

    The title compounds, C10H11BrO4, (I), and C9H9BrO4, (II), are derivatives of bromo-hy-droxy-benzoic acids. Compound (II) crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. In both (I) and (II), the O-CH2-O-CH3 side chain is not in its fully extended conformation; the O-C-O-C torsion angle is 67.3 (3) ° in (I), and -65.8 (3) and -74.1 (3)° in mol-ecules A and B, respectively, in compound (II). In the crystal of (I), mol-ecules are linked by C-H⋯O hydrogen bonds, forming C(5) chains along [010]. The chains are linked by short Br⋯O contacts [3.047 (2) Å], forming sheets parallel to the bc plane. The sheets are linked via C-H⋯π inter-actions, forming a three-dimensional architecture. In the crystal of (II), mol-ecules A and B are linked to form R 2 (2)(8) dimers via two strong O-H⋯O hydrogen bonds. These dimers are linked into ⋯A-B⋯A-B⋯A-B⋯ [C 2 (2)(15)] chains along [011] by C-H⋯O hydrogen bonds. The chains are linked by slipped parallel π-π inter-actions [inter-centroid distances = 3.6787 (18) and 3.8431 (17) Å], leading to the formation of slabs parallel to the bc plane.

  4. N-(4-Meth-oxy-phen-yl)-6-methyl-2-phenyl-5-{[4-(tri-fluoro-meth-yl)anilino]meth-yl}pyrimidin-4-amine.

    Science.gov (United States)

    Cieplik, Jerzy; Pluta, Janusz; Bryndal, Iwona; Lis, Tadeusz

    2013-11-27

    The title compound, C26H23F3N4O, crystallizes with two symmetry-independent mol-ecules in the asymmetric unit, denoted A and B, which differ mainly in the rotation of the meth-oxy-phenyl ring. The -CF3 group of mol-ecule B is disordered by rotation, with the F atoms split over two sets of sites; the occupancy factor for the major component is 0.853 (4). The dihedral angles between the pyrimidine ring and the attached phenyl, meth-oxy-phenyl and tri-fluoro-methyl-phenyl rings are 8.1 (2), 37.5 (2) and 70.7 (2)°, respectively, in mol-ecule A, and 9.3 (2), 5.3 (2) and 79.7 (2)° in mol-ecule B. An intra-molecular N-H⋯N hydrogen bond occurs in each mol-ecule. In the crystal, two crystallographically independent mol-ecules associate into a dimer via a pair of N-H⋯N hydrogen bonds, with a resulting R 2 (2)(12) ring motif and π-π stacking inter-actions [centroid-centroid distance = 3.517 (4) Å] between the pyrimidine rings. For the A mol-ecules, there are inter-molecular C-H⋯O hydrogen bonds between an aryl C atom of meth-oxy-phenyl ring and a meth-oxy O atom of an adjacent mol-ecule. A similar inter-action is lacking in the B mol-ecules.

  5. (E)-2-[1-(1-Benzothio-phen-2-yl)ethyl-idene]-N-phenyl-hydrazinecarboxamide.

    Science.gov (United States)

    Kayed, Safa'a Faris; Farina, Yang; Simpson, Jim; Baba, Ibrahim

    2011-10-01

    The title compound, C(17)H(15)N(3)OS, crystallizes with two unique mol-ecules, denoted 1 and 2, in the asymmetric unit. The two mol-ecules are closely similar and overlay with an r.m.s. deviation of 0.053 Å. Both mol-ecules adopt E configurations with respect to the C=N bonds. The dihedral angles between the benzothio-phene groups and N-bound phenyl rings are 36.36 (9)° for mol-ecule 1 and 29.71 (9)° for mol-ecule 2. The C=N-NH-C(O)NH ethyl-idene-hydrazinecarboxamide units are also reasonably planar, with r.m.s. deviations of 0.061 and 0.056 Å, respectively, for the two mol-ecules. The methyl substituents lie 0.338 (3) and 0.396 (3) Å, respectively, from these planes. The C=N-NH-C(O)NH planes are inclined to the phenyl rings at 13.65 (11) and 15.56 (11)°, respectively, in mol-ecules 1 and 2. This conformation is enhanced by weak intra-molecular C-H⋯O hydrogen bonds between ortho-H atoms of the two phenyl rings and the carbonyl O atoms, which generate S(6) rings in each mol-ecule. In the crystal, pairs of mol-ecules are linked by pairs of inter-molecular N-H⋯O hydrogen bonds into dimers. Alternating dimers are further inter-connected by weak C-H⋯O contacts into zigzag rows along b. The rows are stacked along a by C-H⋯π contacts involving the benzene ring from molecule 2 and the thiophene ring from molecule 1 of adjacent benzothio-phene units.

  6. Crystal structure of (1,3-di-tert-butyl-η(5)-cyclo-penta-dien-yl)tri-methyl-hafnium(IV).

    Science.gov (United States)

    Pérez-Redondo, Adrián; Varela-Izquierdo, Víctor; Yélamos, Carlos

    2015-05-01

    The mol-ecule of the title organometallic hafnium(IV) com-pound, [Hf(CH3)3(C13H21)] or [HfMe3(η(5)-C5H3-1,3- (t) Bu2)], adopts the classical three-legged piano-stool geometry for mono-cyclo-penta-dienylhafnium(IV) derivatives with the three methyl groups bonded to the Hf(IV) atom at the legs. The C atoms of the two tert-butyl group bonded to the cyclo-penta-dienyl (Cp) ring are 0.132 (5) and 0.154 (6) Å above the Cp least-squares plane. There are no significant inter-molecular inter-actions present between the mol-ecules in the crystal structure.

  7. Crystal structure of 4,5-bis-(3,4,5-tri-meth-oxy-phen-yl)-2H-1,2,3-triazole methanol monosolvate.

    Science.gov (United States)

    Madadi, Nikhil Reddy; Penthala, Narsimha Reddy; Bommagani, Shobanbabu; Parkin, Sean; Crooks, Peter A

    2014-10-01

    The title compound, C20H23N3O6·CH3OH, was synthesized by [3 + 2] cyclo-addition of (Z)-2,3-bis-(3,4,5-tri-meth-oxy-phen-yl)acrylo-nitrile with sodium azide and ammonium chloride in DMF/water. The central nitro-gen of the triazole ring is protonated. The dihedral angles between the triazole ring and the 3,4,5-tri-meth-oxy-phenyl ring planes are 34.31 (4) and 45.03 (5)°, while that between the 3,4,5-tri-meth-oxy-phenyl rings is 51.87 (5)°. In the crystal, the mol-ecules, along with two methanol solvent mol-ecules are linked into an R (4) 4(10) centrosymmetric dimer by N-H⋯O and O-H⋯N hydrogen bonds.

  8. Crystal structure of cis-bis-(μ-β-alanine-κ(2) O:O')bis[tri-chlorido-rhenium(III)](Re-Re) sesquihydrate.

    Science.gov (United States)

    Golichenko, Alexander A; Domasevitch, Konstantin V; Kytova, Dina E; Shtemenko, Alexander V

    2015-01-01

    The structure of the title compound, [Re2Cl6(C3H7NO2)2]·1.5H2O, comprises a dinuclear complex cation [Re-Re = 2.2494 (3) Å] involving cis-oriented double carboxyl-ate bridges, four equatorial chloride ions and two weakly bonded chloride ligands in the axial positions at the two rhenium(III) atoms. In the crystal, two complex mol-ecules and two water mol-ecules constitute hydrogen-bonded dimers, while an extensive hydrogen-bonding network involving the groups of the zwitterionic ligand is important for generation of the framework. An additional partially occupied water molecule is disordered over two sets of sites about a symmetry centre with a site-occupancy ratio of 0.3:0.2.

  9. Crystal structure of N-(tert-but-oxy-carbon-yl)glycyl-(Z)-β-bromo-dehydro-alanine methyl ester [Boc-Gly-(β-Br)((Z))ΔAla-OMe].

    Science.gov (United States)

    Lenartowicz, Paweł; Makowski, Maciej; Zarychta, Bartosz; Ejsmont, Krzysztof

    2014-12-01

    The title compound, C11H17BrN2O5, is a de-hydro-amino acid with a C=C bond between the α- and β-C atoms. The amino acid residues are linked trans to each other and there are no strong intra-molecular hydrogen bonds. The torsion angles indicate a non-helical conformation of the mol-ecule. The dipeptide folding is influenced by an inter-molecular N-H⋯O hydrogen bond and also minimizes steric repulsion. In the crystal, mol-ecules are linked by strong N-H⋯O hydrogen bonds, generating (001) sheets. The sheets are linked by weak C-H⋯O and C-H⋯Br bonds and short Br⋯Br [3.4149 (3) Å] inter-actions.

  10. Crystal structures of three (trichloromethyl)(carbamoyl)disulfanes.

    Science.gov (United States)

    Goldenberg, Barbara L; Young, Victor G; Barany, George

    2015-10-01

    The present paper reports crystallographic studies on three related compounds that were of inter-est as precursors for synthetic and mechanistic work in organosulfur chemistry, as well as to model nitro-gen-protecting groups: (N-methyl-carbamo-yl)(tri-chloro-meth-yl)disulfane, C3H4Cl3NOS2, (1), (N-benzyl-carbamo-yl)(tri-chloro-meth-yl)disulfane, C9H8Cl3NOS2, (2), and (N-methyl-N-phenyl-carbamo-yl)(tri-chloro-meth-yl)disulfane, C9H8Cl3NOS2, (3). Their mol-ecular structures, with similar bond lengths and angles for the CCl3SS(C=O)N moieties, are confirmed. Compounds (1) and (3) both crystallized with two independent mol-ecules in the asymmetric unit. Classical hydrogen bonding, as well as chlorine-dense regions, are evident in the crystal packing for (1) and (2). In the crystal of (1), mol-ecules are linked via N-H⋯O hydrogen bonds forming chains along [110], which are linked by short Cl⋯Cl and S⋯O contacts forming sheets parallel to (001). In the crystal of (2), mol-ecules are linked via N-H⋯O hydrogen bonds forming chains along [001], which in turn are linked by pairs of short O⋯Cl contacts forming ribbons along the c-axis direction. In the crystal of (3), there are no classical hydrogen bonds present and the chlorine-dense regions observed in (1) and (2) are lacking.

  11. Crystal structure of 1-[2-(2,6-di-chloro-phen-yl)-4,5-diphenyl-1H-imidazol-1-yl]propan-2-ol.

    Science.gov (United States)

    Akkurt, Mehmet; Jasinski, Jerry P; Mohamed, Shaaban K; Marzouk, Adel A; Albayati, Mustafa R

    2015-05-01

    The central imidazole ring of the title compound, C24H20Cl2N2O, is twisted with respect to with the planes of the 2,6-di-chloro-benzene and two phenyl rings, making dihedral angles of 74.06 (18), 28.52 (17) and 67.65 (18)°, respectively. The phenyl ring not adjacent to the N-bonded 2-hy-droxy-propyl group shows the greatest twist, presumably to minimize steric inter-actions. In the crystal, mol-ecules are linked by O-H⋯N and C-H⋯O hydrogen-bond contacts into chains along the a-axis direction. The series of parallel chains form a two-dimensional sheet approximately parallel to the bc diagonal. In addition, C-H⋯π inter-actions are observed between the sheets. The atoms of the 2-hy-droxy-propyl group and the N atom of the 1H-imidazole ring to which it is bonded are disordered over two sets of sites, with an occupancy ratio of 0.722 (5):0.278 (5). The structure was refined as an inversion twin.

  12. Crystal structure of 1-[2-(4-nitro-phen-yl)-4,5-diphenyl-1H-imidazol-1-yl]propan-2-ol.

    Science.gov (United States)

    Simpson, Jim; Mohamed, Shaaban K; Marzouk, Adel A; Abdelhamid, Antar A; Albayati, Mustafa R

    2017-09-01

    The title compound, C24H21N3O3, crystallizes with two unique but closely r.m.s. overlay fit = 0.215 Å) comparable mol-ecules (1 and 2) in the asymmetric unit of the triclinic unit cell. In molecule 1, the dihedral angles between the central imidazlole ring and the benzene-ring substituents are 42.51 (9), 45.41 (9) and 56.92 (8)°, respectively. Comparable data for molecule 2 are 39.36 (10), 34.45 (11) and 60.34 (8)°, respectively. The rings at the 2-positions carry p-nitro substituents that subtend dihedral angles of 12.9 (4)° in mol-ecule 1 and 11.7 (4)° in mol-ecule 2 to their respective benzene ring planes. The imidazole rings also have propan-2-ol substituents on the 1-N atoms, which adopt extended conformations for the N-C-C-C chains. In the crystal, classical O-H⋯N hydrogen bonds combine with C-H⋯O, C-H⋯N and C-H⋯π(ring) hydrogen bonds and stack the molecules along the a-axis direction.

  13. Crystal structure of ethyl 3-amino-6-methyl-2-[(4-methyl-phen-yl)carbamo-yl]-4-[(E)-2-phenyl-ethen-yl]thieno[2,3-b]pyridine-5-carboxyl-ate monohydrate.

    Science.gov (United States)

    Mague, Joel T; Akkurt, Mehmet; Mohamed, Shaaban K; Bakhite, Etify A; Albayati, Mustafa R

    2016-03-01

    In the title mol-ecule, C27H25N3O3S·H2O, the dihedral angle between the planes of the thienyl ring and the pendant p-tolyl group is 39.25 (6)°, while that between the pyridine ring and the pendant phenyl ring is 44.37 (6)°. In addition, there is a slight twist in the bicyclic core, with a dihedral angle of 2.39 (4)° between the thienyl and pyridine rings. The conformation of the carbamoyl moiety is partially determined by an intra-molecular N-H⋯O hydrogen bond. In the crystal, complementary N-H⋯O hydrogen bonds form dimers which are then associated into chains parallel to the c axis through O-H⋯N hydrogen bonds involving the water mol-ecule of crystallization. Electron density associated with an additional solvent mol-ecule of partial occupancy and disordered about a twofold axis was removed with the SQUEEZE procedure in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9-18]. The given chemical formula and other crystal data do not take into account the unknown solvent molecule(s).

  14. Crystal structure of bis-[tetra-kis-(tri-phenyl-phosphane-κP)silver(I)] (nitrilo-tri-acetato-κ(4) N,O,O',O'')(tri-phenyl-phosphane-κP)argentate(I) with an unknown amount of methanol as solvate.

    Science.gov (United States)

    Noll, Julian; Korb, Marcus; Lang, Heinrich

    2016-03-01

    The structure of the title compound, [Ag(C18H15P)4]2[Ag(C6H6NO6)(C18H15P)], exhibits trigonal (P-3) symmetry, with a C 3 axis through all three complex ions, resulting in an asymmetric unit that contains one third of the atoms present in the formula unit. The formula unit thus contains two of the cations, one anion and disordered mol-ecules of methanol as the packing solvent. Attempts to refine the solvent model were unsuccessful, indicating uninter-pretable disorder. Thus, the SQUEEZE procedure in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9-18] was applied, accounting for 670 electrons per unit cell, representing approximately 18 mol-ecules of methanol in the formula unit. The stated crystal data for M r, μ etc do not take these into account.

  15. Crystal structure of 5,5'-bis-(di-methyl-amino)-N,N'-(3-methyl-3-aza-pentane-1,5-di-yl)di(naphthalene-1-sulfonamide).

    Science.gov (United States)

    Horne, Toyketa V; Haque, Syed A; Barton, Adrianne; Hossain, Md Alamgir

    2015-12-01

    In the title compound, C29H37N5O4S2, two arms substituted with dansyl derivatives are connected to a central tertiary amine, where the dihedral angle between the planes of two dansyl units is 56.39 (4)°. Each arm contains a sulfonamide functional group and both N-H groups in the compound are pointed to the same side. The central part of the mol-ecule is disordered over three sets of sites with a refined occupancy ratio of 0.547 (4):0.328 (4):0.125 (3). No intra-molecular π-π or hydrogen-bonding inter-actions are observed. In the crystal, mol-ecules are linked via pairs of N-H⋯O inter-actions involving the same acceptor atom, forming inversion dimers. In addition, C-H⋯O inter-actions exist between molecules, providing further stabilization of dimers.

  16. Crystal structure of 1-(2,4-di-methyl-phen-yl)-2-(4-tri-methyl-silyl-1H-1,2,3-triazol-1-yl)ethanone.

    Science.gov (United States)

    Venkatesh, G B; Nagarajaiah, H; Prasad, N L; HariPrasad, S; Begum, Noor Shahina

    2014-12-01

    The asymmetric unit of the title compound, C15H21N3OSi, contains two mol-ecules with similar conformations (r.m.s. overlay fit for the 20 non-H atoms = 0.163 Å). The dihedral angles between the planes of the 1,2,3-triazole and 2,4-di-methyl-benzene rings are 27.0 (3) and 19.5 (3)°. In the crystal, mol-ecules are linked by very weak C-H⋯O and C-H⋯N hydrogen bonds to generate [100] chains. The chains are cross-linked by C-H⋯π inter-actions.

  17. Crystal structure of tri-aqua-(2,6-di-methyl-pyrazine-κN (4))bis-(thio-cyanato-κN)manganese(II) 2,5-di-methyl-pyrazine disolvate.

    Science.gov (United States)

    Suckert, Stefan; Wöhlert, Susanne; Jess, Inke; Näther, Christian

    2015-12-01

    In the crystal structure of the title complex, [Mn(NCS)2(C6H8N2)(H2O)3]·2C6H8N2, the Mn(II) cation is coordinated by two terminally N-bonded thio-cyanate anions, three water mol-ecules and one 2,6-di-methyl-pyrazine ligand within a slightly distorted N3O3 octa-hedral geometry; the entire complex mol-ecule is generated by the application of a twofold rotation axis. The asymmetric unit also contains an uncoordinating 2,5-di-methyl-pyrazine ligand in a general position. Obviously, the coordination to the 2,6-di-methyl-pyrazine ligand is preferred because coordination to the 2,5-di-methyl-pyrazine is hindered due to the bulky methyl group proximate to the N atom. The discrete complexes are linked by water-O-H⋯N(2,6-di-methyl-pyzazine/2,5-di-methyl-pyza-zine) hydrogen bonding, forming a three-dimensional network. In the crystal, mol-ecules are arranged in a way that cavities are formed in which unspecified, disordered solvent molecules reside. These were modelled employing the SQUEEZE routine in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9-18]. The composition of the unit cell does not take into account the presence of the unspecified solvent.

  18. Crystal structure of bis-(2-{[1,1-bis-(hy-droxy-meth-yl)-2-oxidoeth-yl]imino-meth-yl}-6-meth-oxy-phenolato)manganese(IV) 0.39-hydrate.

    Science.gov (United States)

    Buvaylo, Elena A; Vassilyeva, Olga Yu; Skelton, Brian W

    2015-11-01

    The title compound, [Mn(C12H15NO5)2]·0.39H2O, is a 0.39 hydrate of the isostructural complex bis-(2-{[1,1-bis-(hy-droxy-meth-yl)-2-oxidoeth-yl]imino-meth-yl}-6-meth-oxy-phenolato)manganese(IV) that has previously been reported by Back, Oliveira, Canabarro & Iglesias [Z. Anorg. Allg. Chem. (2015), 641, 941-947], based on room-temperature data. The current structure that was determined at 100 K reveals a lengthening of the c cell parameter compared with the published one due to the incorporation of the partial occupancy water mol-ecule. The title compound crystallizes in the tetra-gonal chiral space group P41212; the neutral [Mn(IV)(C12H15NO5)2] mol-ecule is situated on a crystallographic C 2 axis. The overall geometry about the central manganese ion is octa-hedral with an N2O4 core; each ligand acts as a meridional ONO donor. The coordination environment of Mn(IV) at 100 K displays a difference in one of the two Mn-O bond lengths, compared with the room-temperature structure. In the crystal, the neutral mol-ecules are stacked in a helical fashion along the c-axis direction.

  19. Crystal structure of bis-[1,3-bis-(2,6-diiso-propyl-phen-yl)imidazol-2-yl-idene]silver(I) chloride tetrahydro-furan monosolvate.

    Science.gov (United States)

    Sänger, Inge; Lerner, Hans-Wolfram; Bolte, Michael

    2015-05-01

    In the title salt, [Ag(C27H36N2)2]Cl·C4H8O, the Ag(I) atom is coordinated by two 1,3-bis-(2,6-di-methyl-phen-yl)imidazol-2-yl-idene ligands. The imidazole rings are inclined to one another by 46.69 (13)° and the benzene rings in each ligand are almost normal to the imdazole ring to which they are attached, with dihedral angles varying from 82.39 (13) to 88.27 (12)°. There are C-H⋯π inter-actions present in the cation, involving the two ligands, and the solvent mol-ecule is linked to the cation via a C-H⋯O hydrogen bond. In the crystal, mol-ecules are linked by trifurcated C-H⋯(Cl,Cl,Cl) hydrogen bonds, forming slabs parallel to (101). One isopropyl group is disordered over two sets of sites with an occupancy ratio of 0.447 (17):0.553 (17) and the THF mol-ecule is disordered over two positions with an occupancy ratio of 0.589 (6):0.411 (6).

  20. Crystal structure of poly[di-aqua-(μ-2-carb-oxy-acetato-κ(3) O,O':O'')(2-carb-oxy-acetato-κO)di-μ-chlorido-dicobalt(II)].

    Science.gov (United States)

    Bouaoud, Yasmina; Setifi, Zouaoui; Buvailo, Andrii; Potaskalov, Vadim A; Merazig, Hocine; Dénés, Georges

    2016-01-01

    The asymmetric unit of the title polymer, [Co2(C3H3O4)2Cl2(H2O)2] n , comprises one Co(II) atom, one water mol-ecule, one singly deprotonated malonic acid mol-ecule (HMal(-); systematic name 2-carb-oxy-acetate) and one Cl(-) anion. The Co(II) atom is octa-hedrally coordinated by the O atom of a water mol-ecule, by one terminally bound carboxyl-ate O atom of an HMal(-) anion and by two O atoms of a chelating HMal(-) anion, as well as by two Cl(-) anions. The Cl(-) anions bridge two Co(II) atoms, forming a centrosymmetric Co2Cl2 core. Each malonate ligand is involved in the formation of six-membered chelate rings involving one Co(II) atom of the dinuclear unit and at the same time is coordinating to another Co(II) atom of a neighbouring dinuclear unit in a bridging mode. The combination of chelating and bridging coordination modes leads to the formation of a two-dimensional coordination polymer extending parallel to (001). Within a layer, O-Hwater⋯Cl and O-Hwater⋯O hydrogen bonds are present. Adjacent layers are linked through O-H⋯O=C hydrogen bonds involving the carb-oxy-lic acid OH and carbonyl groups.

  1. Crystal structure of 4-meth-oxy-quinazoline.

    Science.gov (United States)

    El-Hiti, Gamal A; Smith, Keith; Hegazy, Amany S; Alshammari, Mohammed B; Kariuki, Benson M

    2014-12-01

    The title compound, C9H8N2O, is almost planar, with the C atom of the meth-oxy group deviating from the mean plane of the quinazoline ring system (r.m.s. deviation = 0.011 Å) by 0.068 (4) Å. In the crystal, mol-ecules form π-π stacks parallel to the b-axis direction [centroid-centroid separation = 3.5140 (18) Å], leading to a herringbone packing arrangement.

  2. Crystal structure of 11-(2,3-di-meth-oxy-phen-yl)-14-methyl-12-oxa-8,14-di-aza-tetra-cyclo-[8.3.3.0(1,10).0(2,7)]hexa-deca-2(7),3,5-triene-9,13-dione.

    Science.gov (United States)

    Savithri, M P; Suresh, M; Raghunathan, R; Raja, R; SubbiahPandi, A

    2015-05-01

    The title compound, C22H22N2O5, contains two conformationally similar mol-ecules (A and B) in its the asymmetric unit (r.m.s. overlay fit for the 29 non-H atoms = 0.194 Å). In each mol-ecule, the lactone ring has an envelope conformation with the spiro C atom as the flap. In the crystal, A+A and B+B inversion dimers linked by pairs of N-H⋯O hydrgen bonds occur; in both cases, R 2 (2)(8) loops are generated. A weak C-H⋯O inter-action is also observed, which links the dimers into [010] chains.

  3. Crystal structure of an alternating octamer r(GUAUGUA)dC with adjacent G x U wobble pairs.

    Science.gov (United States)

    Biswas, R; Wahl, M C; Ban, C; Sundaralingam, M

    1997-04-18

    The crystal structure of the RNA duplex, r(GUAUGUA)dC, with a 3'-terminal deoxy C residue, has been determined at 1.38 A resolution. The r(GUAUGU) hexameric consensus sequence is present at the exon-intron junction in pre-mRNAs of yeast and higher eukaryotic organisms. The crystal belongs to the rhombohedral space group R3. The hexagonal unit cell dimensions are a = b = 39.71 A, c = 68.15 A and gamma = 120 degrees with one duplex in the asymmetric unit. The structure was solved using the molecular replacement method. The final model contains 332 atoms of the duplex and 67 solvent molecules. The R-factor is 17.6% (Rfree of 23.1%) for 4035 reflections with F > or = 1.5sigma(F) in the resolution range 10.0 to 1.38 A. The duplex is of the A-type with a pseudodyad relating the two strands. The RNA helix is slightly distorted, in spite of the presence of two adjacent G x U wobble base-pairs located at the center of the helix. The twist angle between the wobble pairs, 38.1 degrees, is above the average value and those between the wobble base-pairs and the flanking Watson-Crick base-pairs, 26.7 degrees and 26.3 degrees, respectively, are lower than the average values. The twist between the junction base-pairs are about 24 degrees. The G x U wobble pairs are bridged by water molecules and solvated in the grooves. G x U base-pairs are as stable as the Watson-Crick A x U pairs and only slightly less stable than the G x C pairs accounting for their frequent occurrence in RNA.

  4. Crystal structure of tetra-kis-(μ3-2-{[1,1-bis-(hy-droxy-meth-yl)-2-oxidoeth-yl]imino-meth-yl}-6-meth-oxy-phenolato)tetra-kis-[aqua-copper(II)]: a redetermination at 200 K.

    Science.gov (United States)

    Buvaylo, Elena A; Vassilyeva, Olga Yu; Skelton, Brian W

    2015-10-01

    The crystal structure of the tetra-nuclear title compound, [Cu4(C12H15NO5)4(H2O)4], has been previously reported by Back, Oliveira, Canabarro & Iglesias [Z. Anorg. Allg. Chem. (2015), 641, 941-947], based on room-temperature data. In the previously published structure, no standard uncertainties are recorded for the deprotonated hy-droxy-methyl group and water mol-ecule O atoms coordinating to the metal atom indicating that they were not refined; furthermore, the H atoms of some OH groups and water mol-ecules have not been positioned accurately. Since the current structure was determined at a lower temperature, all atoms, including the H atoms of these hy-droxy groups and the water mol-ecule, have been determined more accurately resulting in improved standard uncertainties in the bond lengths and angles. Diffraction data were collected at 200 K, rather than the more usual 100 K, due to apparent disordering at lower temperatures. In addition, it is now possible to report intra- and inter-molecular O-H⋯O inter-actions. In the title complex molecule, which has crystallographic -4 symmetry, the Cu(II) ions are coordinated by the tridentate Schiff base ligands and water mol-ecules, forming a tetra-nuclear Cu4O4 cubane-like core. The Cu(II) ion adopts a CuNO5 elongated octa-hedral environment. The coordination environment of Cu(II) at 200 K displays a small contraction of the Cu-N/O bonds, compared with the room-temperature structure. In the crystal lattice, the neutral clusters are linked by inter-molecular O-H⋯O hydrogen bonds into a one-dimensional hydrogen-bonding network propagating along the b axis.

  5. Crystal structure of tris-(trans-1,2-cyclo-hexa-ne-diamine-κ(2) N,N')chromium(III) tetra-chlorido-zincate chloride trihydrate from synchrotron data.

    Science.gov (United States)

    Moon, Dohyun; Choi, Jong-Ha

    2016-05-01

    The structure of the title double salt, [Cr(rac-chxn)3][ZnCl4]Cl·3H2O (chxn is trans-1,2-cyclo-hexa-nedi-amine; C6H14N2), has been determined from synchrotron data. The Cr(III) ion is coordinated by six N atoms of three chelating chxn ligands, displaying a slightly distorted octa-hedral coordination environment. The distorted tetra-hedral [ZnCl4](2-) anion, the isolated Cl(-) anion and three lattice water mol-ecules remain outside the coordination sphere. The Cr-N(chxn) bond lengths are in a narrow range between 2.0737 (12) and 2.0928 (12) Å; the mean N-Cr-N bite angle is 82.1 (4)°. The crystal packing is stabilized by hydrogen-bonding inter-actions between the amino groups of the chxn ligands and the water mol-ecules as donor groups, and O atoms of the water mol-ecules, chloride anions and Cl atoms of the [ZnCl4](2-) anions as acceptor groups, leading to the formation of a three-dimensional network. The [ZnCl4](2-) anion is disordered over two sets of sites with an occupancy ratio of 0.94:0.06.

  6. Crystal structures of (±)-(1SR,5SR,6SR,7SR,10SR,11SR,13RS,14SR)-13-hy-droxy-7-meth-oxy-meth-oxy-11,15,18,18-tetra-methyl-3-oxo-2,4-dioxa-tetra-cyclo-[12.3.1.0(1,5).0(6,11)]octa-dec-15-en-10-yl benzoate, its 13-epimer and 13-one derivative.

    Science.gov (United States)

    Oishi, Takeshi; Fukaya, Keisuke; Yamaguchi, Yu; Sugai, Tomoya; Watanabe, Ami; Sato, Takaaki; Chida, Noritaka

    2015-05-01

    The title compounds, C29H38O8·0.25C5H12, (A), C29H38O8, (B), and C29H36O8, (C), are tetra-cyclic benzoates possessing a taxane skeleton with a fused dioxolane ring as the core structure. In the asymmetric unit of (A), there are two independent benzoate mol-ecules (A and A') and a half mol-ecule of solvent pentane disordered about an inversion center. The mol-ecular conformations of (A), (B) and (C) are similar except for the flexible meth-oxy-meth-oxy group. The cyclo-hexane, cyclo-hexene and central cyclo-octane rings adopt chair, half-chair and chair-chair (extended crown) forms, respectively. The dioxolane rings are essentially planar, while the dioxolane ring of A' is slightly twisted from the mean plane. In the crystal of (A), inter-molecular O-H⋯O, C-H⋯O and C-H⋯π inter-actions link the independent benzoates alternately, forming a chain structure. In the crystals of (B) and (C), mol-ecules are linked through O-H⋯O and C-H⋯π inter-actions, and C-H⋯O hydrogen bonds, respectively, into similar chains. Further, weak inter-molecular C-H⋯O inter-actions connect the chains into a three-dimensional network in (A) and a sheet in (B), whereas no other interactions are observed for (C).

  7. Crystal structure of 2,4,6-tris-(cyclo-hex-yloxy)-1,3,5-triazine.

    Science.gov (United States)

    Sankolli, Ravish; Hauser, Jürg; Row, T N Guru; Hulliger, Jürg

    2015-11-01

    The title compound, C21H33N3O3, is a tri-substituted cyclo-hex-yloxy triazine. In the crystal, the triazine rings form (C3i-PU) Piedfort units. The inter-centroid distance of the π-π inter-action involving the triazine rings is 3.3914 (10) Å. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming ribbons propagating along [1-10]. There are also weak C-H⋯N and C-H⋯O contacts present, linking inversion-related ribbons, forming a three-dimensional structure.

  8. Crystal structure of paddle-wheel sandwich-type [Cu2{(CH3)2CO}{μ-Fe(η(5)-C5H4C N)2}3](BF4)2·(CH3)2CO.

    Science.gov (United States)

    Strehler, Frank; Korb, Marcus; Lang, Heinrich

    2015-02-01

    The mol-ecular structure of (acetone-κO)tris-(μ-ferrocene-1,1'-dicarbo-nitrile-κ(2) N:N')dicopper(I) bis-(tetra-fluorido-borate) acetone monosolvate, [Cu2Fe3(C6H4N)6(C3H6O)](BF4)2·C3H6O, consists of two Cu(I) ions bridged by a ferrocene-1,1'-dicarbo-nitrile moiety in a paddle-wheel-architectured sandwich complex with two BF4 (-) units as counter-ions. One of the latter is equally disordered over two sets of sites. The two Cu(I) ions are complexed in a trigonal-planar manner by three nitrile N-donor atoms. Further inter-actions by the O atom of an acetone mol-ecule to one of the Cu(I) atoms and a weak η(2),π-inter-action of two atoms of a cyclo-penta-dienyl ring to the other Cu(I) atom complete a distorted trigonal-pyramidal environment for each of the metal ions. A further acetone mol-ecule is also present as a solvent mol-ecule. The crystal packing is consolidated by several π-π inter-actions.

  9. Crystal structure of 5-[(4-carb-oxy-benz-yl)-oxy]isophthalic acid.

    Science.gov (United States)

    Faizi, Md Serajul Haque; Ahmad, Musheer; Ali, Akram; Potaskalov, Vadim A

    2016-08-01

    The mol-ecular shape of the title compound, C16H12O7, is bent around the central CH2-O bond. The two benzene rings are almost perpendicular to one another, making a dihedral angle of 87.78 (7)°. In the crystal, each mol-ecule is linked to three others by three pairs of O-H⋯O hydrogen bonds, forming undulating sheets parallel to the bc plane and enclosing R 2 (2)(8) ring motifs. The sheets are linked by C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming a three-dimensional network.

  10. Crystal structure of bromido-bis-(naph-thal-en-1-yl)anti-mony(III).

    Science.gov (United States)

    Shawkataly, Omar Bin; Hussien Abdelnasir, Hafiz Malik; Rosli, Mohd Mustaqim

    2014-10-01

    In the title compound, [SbBr(C10H7)2], the Sb(III) atom has a distorted trigonal-pyramidal coordination geometry and the planes of the two naphthalene ring systems make a dihedral angle of 80.26 (18)°. An intra-molecular C-H⋯Br hydrogen bond forms an S(5) ring motif. In the crystal, weak C-H⋯Br inter-actions link the mol-ecules into helical chains along the b-axis direction.

  11. Test techniques for mol ecul ar biol 0gy 0f entomopathogenic fungi%虫生真菌的分子生物学检测技术

    Institute of Scientific and Technical Information of China (English)

    林华峰; 胡萃

    2001-01-01

    线粒体DNA探针、核糖体RNA编码DNA序列分析、随机扩增多态性DNA-聚合酶链式反应、基因组DNA探针和电泳核型分析,五类分子生物学技术在虫生真菌研究中已有应用.本文对此作了介绍,着重阐述了RAPD-PCR技术的特点及其使用此技术的研究成果.

  12. Crystal structure of ethyl (E)-4-(4-chlorophen-yl)-4-meth-oxy-2-oxobut-3-enoate.

    Science.gov (United States)

    Flores, Darlene Correia; Vicenti, Juliano Rosa de Menezes; Pereira, Bruna Ávila; da Silva, Gabriele Marques Dias; Zambiazi, Priscilla Jussiane

    2014-09-01

    In the title compound, C13H13ClO4, the dihedral angle between the chloro-benezene ring and the least-squares plane through the 4-meth-oxy-2-oxobut-3-enoate ethyl ester residue (r.m.s. deviation = 0.0975 Å) is 54.10 (5)°. In the crystal, mol-ecules are connected by meth-oxy-ketone and benzene-carboxyl-ate carbonyl C-H⋯O inter-actions, generating a supra-molecular layer in the ac plane.

  13. Crystal structure of benzene-1,3,5-tri-carb-oxy-lic acid-4-pyridone (1/3).

    Science.gov (United States)

    Staun, Selena L; Oliver, Allen G

    2015-11-01

    Slow co-crystallization of a solution of benzene-1,3,5-tri-carb-oxy-lic acid with a large excess of 4-hy-droxy-pyridine produces an inter-penetrating, three-dimensional, hydrogen-bonded framework consisting of three 4-pyridone and one benzene-1,3,5-tri-carb-oxy-lic acid mol-ecules, C9H6O6·3C5H5NO. This structure represents an ortho-rhom-bic polymorph of the previously reported C-centered, monoclinic structure [Campos-Gaxiola et al. (2014 ▸). Acta Cryst. E70, o453-o454].

  14. catena-Poly[[aqua-(ethyl anilinophospho-nato-κO)sodium(I)]-di-μ-aqua].

    Science.gov (United States)

    Fu, Zhiyong; Bai, Shuqiong

    2008-08-13

    In the title compound, [Na(C(8)H(11)NO(3)P)(H(2)O)(3)](n), the sodium cation is octa-hedrally coordinated by five water mol-ecules and one O-bonded ethyl anilinophospho-nate anion. Four of the water mol-ecules bridge to adjacent sodium ions, resulting in an infinite chain of edge-sharing NaO(6) polyhedra. A network of N-H⋯O and O-H⋯O hydrogen bonds helps to stabilize the crystal structure.

  15. Crystal structure of 5-[4-(di-methyl-amino)-phen-yl]-3-(4-methyl-phen-yl)-4,5-di-hydro-1H-pyrazole-1-carbaldehyde.

    Science.gov (United States)

    Adam, Farook; Samshuddin, Seranthimata; Ameram, Nadiah; Subramaya; Samartha, Laxminarayana

    2015-12-01

    The title compound, C19H21N3O, comprises a central pyrazole ring which is N-connected to an aldehyde group and C-connected twice to substituted benzene rings. The pyrazole ring is twisted on the C-C single bond, and the least-squares plane through this ring forms dihedral angles of 82.44 (5) and 4.52 (5)° with the (di-methyl-amino)-benzene and p-tolyl rings, respectively. In the crystal, weak C-H⋯O hydrogen bonds link mol-ecules into supra-molecular tubes along the b axis.

  16. Crystal structure of 4-(meth-oxy-carbon-yl)phenyl-boronic acid.

    Science.gov (United States)

    Flanagan, Keith J; Senge, Mathias O

    2015-10-01

    In the title compound, C8H9BO4, the meth-oxy-carbonyl group is rotated out of the plane of the benzene ring by 7.70 (6)°. In the crystal, mol-ecules are linked via pairs of O-H⋯O hydrogen bonds, involving the boronic acid OH groups, forming inversion dimers. The dimers are linked via O-H⋯O hydrogen bonds, involving a boronic acid OH group and the carbonyl O atom, forming undulating sheets parallel to (10-2). Within the sheets there are also C-H⋯O hydrogen bonds present, also involving the carbonyl O atom. The sheets are linked via C-H⋯π and offset face-to-face π-inter-actions between inversion-related mol-ecules [inter-centroid distance = 3.7843 (16) Å, inter-planar distance = 3.3427 (4) Å and offset = 1.744 Å], forming a three-dimensional structure.

  17. Crystal structure of (E)-2-hy-droxy-4'-meth-oxy-aza-stilbene.

    Science.gov (United States)

    Chantrapromma, Suchada; Kaewmanee, Narissara; Boonnak, Nawong; Chantrapromma, Kan; Ghabbour, Hazem A; Fun, Hoong-Kun

    2015-06-01

    The title aza-stilbene derivative, C14H13NO2 {systematic name: (E)-2-[(4-meth-oxy-benzyl-idene)amino]-phenol}, is a product of the condensation reaction between 4-meth-oxy-benzaldehyde and 2-amino-phenol. The mol-ecule adopts an E conformation with respect to the azomethine C=N bond and is almost planar, the dihedral angle between the two substituted benzene rings being 3.29 (4)°. The meth-oxy group is coplanar with the benzene ring to which it is attached, the Cmeth-yl-O-C-C torsion angle being -1.14 (12)°. There is an intra-molecular O-H⋯N hydrogen bond generating an S(5) ring motif. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming zigzag chains along [10-1]. The chains are linked via C-H⋯π inter-actions, forming a three-dimensional structure.

  18. Crystal structure of di-bromo-meth-oxy-seselin (DBMS), a photobiologically active pyran-ocoumarin.

    Science.gov (United States)

    Bauri, A K; Foro, Sabine; Rahman, A F M M

    2017-05-01

    The title compound, C15H14Br2O4 [systematic name: rac-(9S,10R)-3,9-dibromo-10-methoxy-8,8-dimethyl-9,10-dihydropyrano[2,3-h]chromen-2(8H)-one], is a pyran-ocoumarin derivative formed by the bromination of seselin, which is a naturally occurring angular pyran-ocoumarin isolated from the Indian herb Trachyspermum stictocarpum. In the mol-ecule, the benzo-pyran ring system is essentially planar, with a maximum deviation of 0.044 (2) Å for the O atom. The di-hydro-pyran ring is in a half-chair conformation and the four essentially planar atoms of this ring form a dihedral angle of 4.6 (2)° with the benzo-pyran ring system. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming chains propagating along [010]. In addition, π-π stacking inter-actions, with centroid-centroid distances of 3.902 (2) and 3.908 (2) Å, link the hydrogen-bonded chains into layers parallel to (001).

  19. Crystal structure of dimethyl 2-((2Z,5Z)-5-(2-meth-oxy-2-oxo-ethyl-idene)-2-{(E)-[2-methyl-5-(prop-1-en-2-yl)cyclo-hex-2-enyl-idene]hydrazinyl-idene}-4-oxo-thia-zolidin-3-yl)fumarate.

    Science.gov (United States)

    N'ait Ousidi, Abdellah; Ait Itto, My Youssef; Auhmani, Aziz; Riahi, Abdelkhalek; Auhmani, Abdelwahed; Daran, Jean-Claude

    2017-02-01

    The crystal structure and the conformation of the title compound, C22H27N3O7S, were determined from the synthetic pathway and by X-ray analysis. This compound is a new 4-thia-zolidinone derivative prepared and isolated as pure product from thio-semicarbazone carvone. The mol-ecule is built up from an oxo-thia-zolidine ring tetra-substituted by a meth-oxy-oxo-ethyl-idene, a maleate, an oxygen and a cyclo-hexyl-idene-hydrazone. The cyclo-hexyl-idene ring is statistically disordered over two positions, resulting in an inversion of configuration for the substituted carbon.

  20. Redetermined crystal structure of N-(β-carb-oxy-eth-yl)-α-isoleucine.

    Science.gov (United States)

    Chandrarekha, M; Srinivasan, N; Krishnakumar, R V

    2015-09-01

    Redetermination of the crystal structure of N-(β-carb-oxy-eth-yl)-α-isoleucine, C9H18N2O3, reported earlier by Nehls et al. [Acta Cryst. (2013), E69, o172-o173], was undertaken in which the ionization state assigned to the mol-ecule as unionized has been modified as zwitterionic in the present work. Single-crystal X-ray intensity data obtained from freshly grown crystals and freely refining the amino H atoms provide enhanced refinement and structural parameters, particularly the hydrogen-bonding scheme. N-H⋯O hydrogen bonds dominate the inter-molecular inter-actions along with a C-H⋯O hydrogen bond. The inter-molecular inter-action pattern is a three-dimensional network. The structure was refined as a two-component perfect inversion twin.

  1. Crystal structure of (3E)-5-nitro-3-(2-phenyl-hydrazinyl-idene)-1H-indol-2(3H)-one.

    Science.gov (United States)

    Velasques, Jecika Maciel; Gervini, Vanessa Carratu; Bortoluzzi, Adaílton João; de Farias, Renan Lira; de Oliveira, Adriano Bof

    2017-02-01

    The reaction between 5-nitro-isatin and phenyl-hydrazine in acidic ethanol yields the title compound, C14H10N4O3, whose mol-ecular structure deviates slightly from a planar geometry (r.m.s. deviation = 0.065 Å for the mean plane through all non-H atoms). An intra-molecular N-H⋯O hydrogen bond is present, forming a ring of graph-set motif S(6). In the crystal, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen-bonding inter-actions into a two-dimensional network along (120), and rings of graph-set motif R2(2)(8), R2(2)(26) and R4(4)(32) are observed. Additionally, a Hirshfeld surface analysis suggests that the mol-ecules are stacked along [100] through C=O⋯Cg inter-actions and indicates that the most important contributions for the crystal structure are O⋯H (28.5%) and H⋯H (26.7%) inter-actions. An in silico evaluation of the title compound with the DHFR enzyme (di-hydro-folate reductase) was performed. The isatin-hydrazone derivative and the active site of the selected enzyme show N-H⋯O(ASP29), N-H⋯O(ILE96) and Cg⋯Cg(PHE33) inter-actions.

  2. Crystal structure of di-chlorido-(2,2':6',2''-terpyridine-κ(3) N,N',N'')zinc: a redeter-min-ation.

    Science.gov (United States)

    Kong, Cheng-Cheng; Zhou, Jia-Zheng; Yu, Jian-Hua; Li, Sheng-Li

    2014-11-01

    The crystal structure of the title compound, [ZnCl2(C15H11N3)], was redetermined based on modern CCD data. In comparison with the previous determination from photographic film data [Corbridge & Cox (1956 ▶). J. Chem. Soc. 159, 594-603; Einstein & Penfold (1966 ▶). Acta Cryst. 20, 924-926], all non-H atoms were refined with anisotropic displacement parameters, leading to a much higher precision in terms of bond lengths and angles [e.g. Zn-Cl = 2.2684 (8) and 2.2883 (11) compared to 2.25 (1) and 2.27 (1) Å]. In the title mol-ecule, the Zn(II) atom is five-coordinated in a distorted square-pyramidal mode by two Cl atoms and by the three N atoms from the 2,2':6',2''-terpyridine ligand. The latter is not planar and shows dihedral angles between the least-squares planes of the central pyridine ring and the terminal rings of 3.18 (8) and 6.36 (9)°. The mol-ecules in the crystal structure pack with π-π inter-actions [centroid-centroid distance = 3.655 (2) Å] between pyridine rings of neighbouring terpyridine moieties. These, together with inter-molecular C-H⋯Cl inter-actions, stablize the three-dimensional structure.

  3. Redetermination of the crystal structure of 3,5-di-methyl-pyrazolium β-octa-molybdate tetra-hydrate.

    Science.gov (United States)

    Amarante, Tatiana R; Gonçalves, Isabel S; Almeida Paz, Filipe A

    2015-12-01

    The title compound, (C5H9N2)4[Mo8O26]·4H2O, was reported previously from a room-temperature data collection from which only the metal atoms could be refined anisotropically [FitzRoy et al. (1989 ▸). Inorg. Chim. Acta, 157, 187-194]. The current redetermination at 180 (2) K models all the non-H atoms with anisotropic displacement parameters and fully describes the supra-molecular N-H⋯O and O-H⋯O hydrogen-bonded network connecting the 3,5-di-methyl-pyrazolium cations, the water mol-ecules of crystallization and the β-octa-molybdate anion. All H atoms involved in the three-dimensional hydrogen-bonding network could be located from difference Fourier maps, with the exception of those of one disordered water mol-ecule, firstly seen in this structural report [refined over two distinct locations with site-occupancy factors of 0.65 (2) and 0.35 (2)]. The complete β-octa-molybdate anion is generated by a crystallographic inversion centre.

  4. Crystal structure of bis-(2,2'-bi-pyridine-κ(2) N,N')bis-(thio-cyanato-κN)mang-anese(II) 2,2'-bi-pyridine monosolvate.

    Science.gov (United States)

    Suckert, Stefan; Jess, Inke; Näther, Christian

    2015-01-01

    In the crystal structure of the mononuclear title compound, [Mn(NCS)2(C10H8N2)2]·C10H8N2, the Mn(II) cation is coordin-ated in an all-cis configuration by two N-bound thio-cyanate anions and two 2,2'-bi-pyridine ligands within a slightly distorted octa-hedral environment. The asymmetric unit consists of one Mn(II) cation, two thio-cyanate anions and two 2,2'-bi-pyridine ligands, as well as two non-coordinating 2,2'-bi-pyridine ligands that are each located on centres of inversion. In the crystal structure, the discrete [Mn(NCS)2(C10H8N2)2] complex mol-ecules are arranged in such a way that cavities are formed, in which the solvent 2,2'-bi-pyridine mol-ecules are located. Apart from van der Waals forces, there are no remarkable inter-molecular inter-actions present in the crystal structure.

  5. Crystal structure of triphenylphosphonium-meth-yl-enetrifluoroborate.

    Science.gov (United States)

    Bateman, Christopher M; Zakharov, Lev N; Abbey, Eric R

    2017-07-01

    The title compound, C19H17BF3P {alternative name: triphen-yl[(tri-fluoro-boran-yl)meth-yl]phosphanium}, was formed by the reaction of tri-phenyl-phosphine with potassium iodo-methyl-tri-fluoro-borate. The mol-ecule features a nearly staggered conformation along the P-C bond and a less than staggered conformation along the C-B bond. In the crystal, weak C-H⋯F hydrogen bonds between the meta-phenyl C-H groups and the tri-fluoro-borate B-F groups form chains of R2(2)(16) rings along [100]. These chains are are further stabilized by weak C-H⋯π inter-actions. A weak intra-molecular C-H⋯F hydrogen bond is also observed.

  6. Crystal structure of a new hybrid compound based on an iodido-plumbate(II) anionic motif.

    Science.gov (United States)

    Mokhnache, Oualid; Boughzala, Habib

    2016-01-01

    Crystals of the one-dimensional organic-inorganic lead iodide-based compound catena-poly[bis-(piperazine-1,4-diium) [[tetra-iodido-plumbate(II)]-μ-iodido] iodide monohydrate], (C4N2H12)2[PbI5]I·H2O, were obtained by slow evaporation at room temperature of a solution containing lead iodide and piperazine in a 1:2 molar ratio. Inorganic lead iodide chains, organic (C4N2H12)(2+) cations, water mol-ecules of crystallization and isolated I(-) anions are connected through N-H⋯·I, N-H⋯OW and OW-H⋯I hydrogen-bond inter-actions. Zigzag chains of corner-sharing [PbI6](4-) octa-hedra with composition [PbI4/1I2/2](3-) running parallel to the a axis are present in the structure packing.

  7. Crystal structure of 2,3-di-methyl-maleic anhydride: continuous chains of electrostatic attraction.

    Science.gov (United States)

    Wiscons, Ren A; Zeller, Matthias; Rowsell, Jesse L C

    2015-08-01

    In the crystal structure of 2,3-di-methyl-maleic anhydride, C6H6O3, the closest non-bonding inter-molecular distances, between the carbonyl C and O atoms of neighboring mol-ecules, were measured as 2.9054 (11) and 3.0509 (11) Å, which are well below the sum of the van der Waals radii for these atoms. These close contacts, as well as packing motifs similar to that of the title compound, were also found in the crystal structure of maleic anhydride itself and other 2,3-disubstituted maleic anhydrides. Computational modeling suggests that this close contact is caused by strong electrostatic inter-actions between the carbonyl C and O atoms.

  8. Crystal structures of the two salts 2-methyl-1H-imidazol-3-ium nitrate-2-methyl-1H-imidazole (1/1) and 2-methyl-1H-imidazol-3-ium nitrate.

    Science.gov (United States)

    Diop, Mouhamadou Birame; Diop, Libasse; Maris, Thierry

    2016-04-01

    The title salts, C4H7N2 (+)·NO3 (-)·C4H6N2, (I), and C4H7N2 (+)·NO3 (-), (II), were obtained from solutions containing 2-methyl-imidazole and nitric acid in different concentrations. In the crystal structure of salt (I), one of the -NH H atoms of the imidazole ring shows half-occupancy, hence only every second mol-ecule is in its cationic form. The nitrate anion in this structure lies on a twofold rotation axis. The neutral 2-methyl-imidazole mol-ecule and the 2-methyl-1H-imidazol-3-ium cation inter-act through N-H⋯N hydrogen bonds to form [(C4H6N2)⋯(C4H7N2)(+)] pairs. These pairs are linked with two nitrate anions on both sides through bifurcated N-H⋯(O,O) hydrogen bonds into chains running parallel to [001]. In the crystal structure of salt (II), the C4H7N2 (+) cation and the NO3 (-) anion are both located on a mirror plane, leading to a statistical disorder of the methyl H atoms. The cations and anions again inter-act through bifurcated N-H⋯(O,O) hydrogen bonds, giving rise to the formation of chains consisting of alternating anions and cations parallel to [100].

  9. Structural characterization of two tetra-chlorido-zincate salts of 4-carb-oxy-1H-imidazol-3-ium: a salt hydrate and a co-crystal salt hydrate.

    Science.gov (United States)

    Martens, Sean J; Geiger, David K

    2017-02-01

    Imidazole-containing compounds exhibit a myriad of pharmacological activities. Two tetra-chlorido-zincate salts of 4-carb-oxy-1H-imidazol-3-ium, ImHCO2H(+), are reported. Bis(4-carb-oxy-1H-imidazol-3-ium) tetra-chlorido-zincate monohydrate, (C4H5N2O2)2[ZnCl4]·H2O, (I), crystallizes as a monohydrate salt, while bis-(4-carb-oxy-1H-imidazol-3-ium) tetra-chlorido-zincate bis-(1H-imidazol-3-ium-4-carboxyl-ato) monohydrate, (C4H5N2O2)2[ZnCl4]·2C4H4N2O2·H2O, (II), is a co-crystal salt with six residues: two ImHCO2H(+) cations, two formula units of the zwitterionic 1H-imidazol-3-ium-4-carboxyl-ate, ImHCO2, one tetra-chlorido-zincate anion and one water mol-ecule disordered over two sites in a 0.60 (4):0.40 (4) ratio. The geometric parameters of the ImHCO2H(+) and the ImHCO2 moieties are the same within the standard uncertainties of the measurements. Both compounds exhibit extensive hydrogen bonding, including involvement of the tetra-chlorido-zincate anion, resulting in inter-connected chains of anions joined by water mol-ecules.

  10. Crystal structure of zwitterionic 3-(2-hy-droxy-2-phospho-nato-2-phosphono-eth-yl)imidazo[1,2-a]pyridin-1-ium monohydrate (minodronic acid monohydrate): a redetermination.

    Science.gov (United States)

    Airoldi, Annalisa; Bettoni, Piergiorgio; Donnola, Monica; Calestani, Gianluca; Rizzoli, Corrado

    2015-01-01

    In a previous study, the X-ray structure of the title compound, C9H12N2O7P2·H2O, was reported [Takeuchi et al., (1998 ▶). Chem. Pharm. Bull. 46, 1703-1709], but neither atomic coordinates nor details of the geometry were published. The structure has been redetermined with high precision as its detailed knowledge is essential to elucidate the presumed polymorphism of minodronic acid monohydrate at room temperature. The mol-ecule crystallizes in a zwitterionic form with cationic imidazolium[1,2a]pyridine and anionic phospho-nate groups. The dihedral angle formed by the planes of the pyridine and imidazole rings is 3.55 (9)°. A short intra-molecular C-H⋯O contact is present. In the crystal, mol-ecules are linked by O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds and π-π inter-actions [centroid-to-centroid distance = 3.5822 (11) Å], forming a three-dimensional structure.

  11. Crystal structure of bis-[(acetato-κO)(imidazolidine-2-thione-κS)bis-(tri-phenyl-phosphane-κP)silver(I)] di-μ-imidazol-idine-2-thione-κ(4) S:S-bis-[(imidazol-id-ine-2-thione-κS)bis-(tri-phenyl-phosphane-κP)silver(I)] di-acetate aceto-nitrile disolvate tetra-hydrate.

    Science.gov (United States)

    Nimthong-Roldán, Arunpatcha; Ratthiwan, Janejira; Lakmas, Sawanya; Wattanakanjana, Yupa

    2016-04-01

    In the title compound, [Ag2(C3H6N2S)4(C18H15P)2](C2H3O2)2·[Ag(C2H3O2)(C3H6N2S)(C18H15P)2]2·2C2H3N·4H2O, the Ag(I) ion in the mononuclear neutral complex exhibits a distorted tetra-hedral environment with coordination by two P atoms from tri-phenyl-phosphane (PPh3) ligands, one S atom of an imidazolidine-2-thione (etu) ligand and one O atom of an acetate anion. The binuclear cationic complex comprises two inversion-related [Ag(C3H6N2S)2(C18H15P)] units with Ag(I) ions bridged by two S atoms from etu ligands forming a four-membered Ag-S-Ag-S ring. Each Ag(I) ion is coordinated by a P atom of a PPh3 ligand, two S atoms of bridging etu ligands and the terminal S atom of an etu ligand in a distorted tetra-hedral environment. In the crystal, the mononuclear complex is linked to lattice water mol-ecules through O-H⋯O and N-H⋯O hydrogen bonds, forming a chain along [100]. In addition, the binuclear complex mol-ecules are connected to acetate anions and lattice water mol-ecules via O-H⋯O, N-H⋯O and O-H⋯S hydrogen bonds, also along [100].

  12. Crystal structure of bis-(3-bromo-pyridine-κN)bis-(O-ethyl di-thio-carbonato-κ(2) S,S')nickel(II).

    Science.gov (United States)

    Kant, Rajni; Kour, Gurvinder; Anthal, Sumati; Neerupama; Sachar, Renu

    2015-01-01

    In the title mol-ecular complex, [Ni(C3H5OS2)2(C5H4BrN)2], the Ni(2+) cation is located on a centre of inversion and has a distorted octa-hedral N2S4 environment defined by two chelating xanthate ligands and two monodentate pyridine ligands. The C-S bond lengths of the thio-carboxyl-ate group are indicative of a delocalized bond and the O-Csp (2) bond is considerably shorter than the O-Csp (3) bond, consistent with a significant contribution of one resonance form of the xanthate anion that features a formal C=O+ unit and a negative charge on each of the S atoms. The packing of the mol-ecules is stabilized by C-H⋯S and C-H⋯π inter-actions. In addition, π-π inter-actions between the pyridine rings [centroid-to-centroid distance = 3.797 (3) Å] are also present. In the crystal structure, mol-ecules are arranged in rows along [100], forming layers parallel to (010) and (001).

  13. Crystal structures of two mononuclear complexes of terbium(III) nitrate with the tripodal alcohol 1,1,1-tris-(hy-droxy-meth-yl)propane.

    Science.gov (United States)

    Gregório, Thaiane; Giese, Siddhartha O K; Nunes, Giovana G; Soares, Jaísa F; Hughes, David L

    2017-02-01

    Two new mononuclear cationic complexes in which the Tb(III) ion is bis-chelated by the tripodal alcohol 1,1,1-tris-(hy-droxy-meth-yl)propane (H3L(Et), C6H14O3) were prepared from Tb(NO3)3·5H2O and had their crystal and mol-ecular structures solved by single-crystal X-ray diffraction analysis after data collection at 100 K. Both products were isolated in reasonable yields from the same reaction mixture by using different crystallization conditions. The higher-symmetry complex dinitratobis[1,1,1-tris-(hy-droxy-meth-yl)propane]-terbium(III) nitrate di-meth-oxy-ethane hemisolvate, [Tb(NO3)2(H3L(Et))2]NO3·0.5C4H10O2, 1, in which the lanthanide ion is 10-coordinate and adopts an s-bicapped square-anti-prismatic coordination geometry, contains two bidentate nitrate ions bound to the metal atom; another nitrate ion functions as a counter-ion and a half-mol-ecule of di-meth-oxy-ethane (completed by a crystallographic twofold rotation axis) is also present. In product aqua-nitratobis[1,1,1-tris-(hy-droxy-meth-yl)propane]-terbium(III) dinitrate, [Tb(NO3)(H3L(Et))2(H2O)](NO3)2, 2, one bidentate nitrate ion and one water mol-ecule are bound to the nine-coordinate terbium(III) centre, while two free nitrate ions contribute to charge balance outside the tricapped trigonal-prismatic coordination polyhedron. No free water mol-ecule was found in either of the crystal structures and, only in the case of 1, di-meth-oxy-ethane acts as a crystallizing solvent. In both mol-ecular structures, the two tripodal ligands are bent to one side of the coordination sphere, leaving room for the anionic and water ligands. In complex 2, the methyl group of one of the H3L(Et) ligands is disordered over two alternative orientations. Strong hydrogen bonds, both intra- and inter-molecular, are found in the crystal structures due to the number of different donor and acceptor groups present.

  14. Crystal structure of (2,11-di-aza-[3.3](2,6)pyridino-phane-κ (4) N,N',N'',N''')(1,6,7,12-tetra-aza-perylene-κ (2) N (1),N (12))ruthenium(II) bis-(hexa-fluorido-phosphate) aceto-nitrile 1.422-solvate.

    Science.gov (United States)

    Brietzke, Thomas; Rottke, Falko Otto; Kelling, Alexandra; Schilde, Uwe; Holdt, Hans-Jürgen

    2014-10-01

    In the title compound, [Ru(C14H16N4)(C16H8N4)](PF6)2·1.422CH3CN, discrete dimers of complex cations, [Ru(L-N4H2)tape](2+) are formed {L-N4H2 = 2,11-di-aza-[3.3](2,6)pyridino-phane; tape = 1,6,7,12-tetra-aza-perylene}, held together by π-π stacking inter-actions via the tape ligand moieties with a centroid-centroid distance of 3.49 (2) Å, assisted by hydrogen bonds between the non-coordinating tape ligand α,α'-di-imine unit and the amine proton of a 2,11-di-aza-[3.3](2,6)-pyridino-phane ligand of the opposite complex cation. The combination of these inter-actions leads to an unusual nearly face-to-face π-π stacking mode. Additional weak C-H⋯N, C-H⋯F, N-H⋯F and P-F⋯π-ring (tape, py) (with F⋯centroid distances of 2.925-3.984 Å) inter-actions are found, leading to a three-dimensional architecture. The Ru(II) atom is coordinated in a distorted octa-hedral geometry, particularly manifested by the Namine-Ru-Namine angle of 153.79 (10)°. The counter-charge is provided by two hexa-fluorido-phosphate anions and the asymmetric unit is completed by aceto-nitrile solvent mol-ecules of crystallization. Disorder was observed for both the hexa-fluorido-phosphate anions as well as the aceto-nitrile solvate mol-ecules, with occupancies for the major moieties of 0.801 (6) for one of the PF6 anions, and a shared occupancy of 0.9215 (17) for the second PF6 anion and a partially occupied aceto-nitrile mol-ecule. A second CH3CN mol-ecule is fully occupied, but 1:1 disordered across a crystallographic inversion center.

  15. Crystal structure of [propane-1,3-diylbis(piperidine-4,1-di-yl)]bis-[(pyridin-4-yl)methanone]-isophthalic acid (1/1).

    Science.gov (United States)

    Murray, Nathan H; Biros, Shannon M; LaDuca, Robert L

    2014-11-01

    In the crystal structure of the title co-crystal, C25H32N4O2·C8H6O4, isophthalic acid and [propane-1,3-diylbis(piperidine-4,1-di-yl)]bis-(pyridin-4-yl-methanone) mol-ecules are connected into supra-molecular chains aligned along the c axis by O-H⋯N hydrogen bonding. These aggregate into supra-molecular layers oriented parallel to the ac plane by C-H⋯O inter-actions. These layers then stack in an ABCD pattern along the b-axis direction by additional C-H⋯O inter-actions to give the full three-dimensional crystal structure. The central chain in the di-pyridyl-amide molecule has an anti-gauche conformation.

  16. Crystal structure of a layered coordination polymer based on a 4(4) net containing Cd(2+) ions and 1,5-bis-(pyridin-4-yl)pentane linkers.

    Science.gov (United States)

    Harrison, William T A; Plater, M John; deSilva, Ben M deSilva; Foreman, Mark R St J

    2014-08-01

    The title compound, poly[[di-aqua-bis-[1,5-bis-(pyridin-4-yl)pentane-κ(2) N:N']cadmium] bis-(perchlorate) 1,5-bis-(pyridin-4-yl)pentane ethanol mono-solvate], [Cd(C15H18N2)2(H2O)2](ClO4)2·C15H18N2·C2H6O, is a layered coordination polymer built up from highly squashed 4(4) nets in which the octa-hedral trans-CdO2N4 nodes (Cd site symmetry -1) are linked by the bifunctional ligands, forming infinite (110) sheets. The cationic sheets are charge-balanced by inter-layer perchlorate ions. A free 1,5-bis-(pyridin-4-yl)pentane mol-ecule and an ethanol mol-ecule of crystallization are also found in the inter-sheet region. A number of O-H⋯O, O-H⋯N and C-H⋯O hydrogen bonds help to consolidate the layered structure.

  17. Crystal structure of (μ-1,4-di-carb-oxy-butane-1,4-di-carboxyl-ato)bis-[bis-(tri-phenyl-phosphane)silver(I)] di-chloro-methane tris-olvate.

    Science.gov (United States)

    Frenzel, Peter; Korb, Marcus; Lang, Heinrich

    2016-02-01

    The mol-ecular structure of the tetra-kis(tri-phenyl-phosphan-yl)disilver salt of butane-1,1,4,4-tetra-carb-oxy-lic acid, [Ag2(C8H8O8)(C18H15P)4]·3CH2Cl2, crystallizes with one and a half mol-ecules of di-chloro-methane in the asymmetric unit. The coordination complex exhibits an inversion centre through the central CH2-CH2 bond. The Ag(I) atom has a distorted trigonal-planar P2O coordination environment. The packing is characterized by inter-molecular T-shaped π-π inter-actions between the phenyl rings of the PPh3 substituents in neighbouring mol-ecules, forming a ladder-type superstructure parallel to [010]. These ladders are arranged in layers parallel to (101). Intra-molecular hydrogen bonds between the OH group and one O atom of the Ag-bonded carboxyl-ate group results in an asymmetric bidendate coordination of the carboxyl-ate moiety to the Ag(I) ion.

  18. Crystal structure of ({(1R,2R)-N,N'-bis-[(quino-lin-2-yl)methyl]cyclo-hexane-1,2-di-amine}-chlorido-iron(III))-μ-oxido-[tri-chlorido-ferrate(III)] chloro-form monosolvate.

    Science.gov (United States)

    Swift, Hannah; Carrig, Molly W; Oshin, Kayode D; Vinokur, Anastasiya I; Desper, John A; Levy, Christopher J

    2017-07-01

    The first Fe(III) atom in the solvated title compound, [Fe2Cl4O(C26H28N4)]·CHCl3, adopts a distorted six-coordinate octa-hedral geometry. It is coordinated by one chloride ligand, four N atoms from the (1R,2R)-N,N'-bis-[(quinolin-2-yl)methyl]cyclo-hexane-1,2-di-amine ligand, and a bridging oxido ligand attached to the second Fe(III) atom, which is also bonded to three chloride ions. A very weak intra-molecular N-H⋯Cl hydrogen bond occurs. In the crystal, the coordination complexes stack in columns, and a grouping of six such columns create channels, which are populated by disordered chloro-form solvent mol-ecules. Although the Fe-Cl bond lengths for the two metal atoms are comparable to the mean Fe-Cl bond lengths as derived from the Cambridge Structural Database, the Fe-O bond lengths are notably shorter. The solvent chloro-form mol-ecule exhibits 'flip' disorder of the C-H moiety in a 0.544 (3):0.456 (3) ratio. The only directional inter-action noted is a weak C-H⋯Cl hydrogen bond.

  19. 6-Amino-5-(1-amino-2,2-dicyano-vin-yl)-3,3a,4,5-tetra-hydro-2H-indene-4-spiro-1'-cyclo-pentane-3a,7-dicarbonitrile-thio-phene-2-carbaldehyde (1/0.5).

    Science.gov (United States)

    Asiri, Abdullah M; Ng, Seik Weng

    2010-09-04

    In each of the two independent indene-4-spiro-pentane mol-ecules in the asymmetric unit of the title 2:1 adduct, C(19)H(18)N(6)·0.5C(5)H(4)OS, the cyclo-hexene ring adopts a half-chair conformation and the cyclo-pentene and cyclo-pentane rings adopt envelope conformations. The mean plane through the cyclo-hexene/cyclo-pentene fused system is aligned at a dihedral angle of 77.9 (1)° with respect to the mean plane through the cyclo-pentane ring in one mol-ecule and 87.0 (1)° in the other. In the crystal, adjacent indene-4-spiro-pentane mol-ecules are linked by N-H⋯N hydrogen bonds into a three-dimensional network. The spaces within the network are occupied by the thio-phene-2-carbaldehyde mol-ecules. The thio-phene-2-carbaldehyde unit is disordered over two positions of equal occupancy. The crystal studied was found to be a non-morohedral twin with two minor twin components of 18.4 and 9.7%.

  20. Crystal structure of 1-isopropyl-4,7-dimethyl-3-nitro-naphthalene.

    Science.gov (United States)

    Benharref, Ahmed; Elkarroumi, Jamal; El Ammari, Lahcen; Saadi, Mohamed; Berraho, Moha

    2015-09-01

    The title compound, C15H17NO2, was synthesized from a mixture of α-himachalene (2-methyl-ene-6,6,9-tri-methylbi-cyclo-[5.4.0(1,7)]undec-8-ene) and β-himachalene (2,6,6,9-tetra-methylbi-cyclo-[5.4.0(1,7)]undeca-1,8-diene), which were isolated from an oil of the Atlas cedar (Cedrus Atlantica). The naphthalene ring system makes dihedral angles of 68.6 (2) and 44.3 (2)°, respectively, with its attached isopropyl C/C/C plane and the nitro group. In the crystal, mol-ecules held together by a C-H⋯O inter-action, forming a chain along [-101].

  1. Hydrogen bonding in the crystal structure of the molecular salt of pyrazole-pyrazolium picrate.

    Science.gov (United States)

    Su, Ping; Song, Xue-Gang; Sun, Ren-Qiang; Xu, Xing-Man

    2016-06-01

    The asymmetric unit of the title organic salt [systematic name: 1H-pyrazol-2-ium 2,4,6-tri-nitro-phenolate-1H-pyrazole (1/1)], H(C3H4N2)2 (+)·C6H2N3O7 (-), consists of one picrate anion and one hydrogen-bonded dimer of a pyrazolium monocation. The H atom involved in the dimer N-H⋯N hydrogen bond is disordered over both symmetry-unique pyrazole mol-ecules with occupancies of 0.52 (5) and 0.48 (5). In the crystal, the component ions are linked into chains along [100] by two different bifurcated N-H⋯(O,O) hydrogen bonds. In addition, weak C-H⋯O hydrogen bonds link inversion-related chains, forming columns along [100].

  2. Crystal structure of 2-{(R)-[1-(4-bromo-phen-yl)eth-yl]imino-meth-yl}-4-(phenyl-diazen-yl)phenol, a chiral photochromic Schiff base.

    Science.gov (United States)

    Moriwaki, Ryoji; Akitsu, Takashiro

    2015-11-01

    The title chiral photochromic Schiff base compound, C21H18BrN3O, was synthesized from (R)-(+)-1-(4-bromo-phen-yl)ethyl-amine and the salicyl-aldehyde of an azo-benzene derivative. The mol-ecule corresponds to the phenol-imine tautomer, the C=N and N-C bond distances being 1.285 (3) and 1.470 (3) Å, respectively. The diazenyl group adopts a trans form, with an N=N distance of 1.256 (3) Å. The hy-droxy group is involved in intra-molecular O-H⋯N hydrogen bonding. In the crystal, C-H⋯π inter-actions consolidate the crystal packing of one-dimensional chains, which exhibits short inter-molecular Br⋯C contacts of 3.400 (3) Å.

  3. Crystal structure of rac-(3a'R,9a'R)-3a'-(indol-3-yl)-1',2',3',3a',4',9a'-hexa-hydro-spiro-[cyclo-pentane-1,9'-penta-leno[1,2-b]indole] p-xylene hemisolvate.

    Science.gov (United States)

    Noland, Wayland E; Worth, Matthew A; Schneerer, Andrew K; Paal, Courtney L; Tritch, Kenneth J

    2015-05-01

    The title compound, C26H26N2·0.5C8H10, is the first reported characterized 2:2 product from acid-catalyzed condensation of indole with cyclo-penta-none and no other 2:2 products were observed. Recrystallization from p-xylene gave the title hemisolvate with the p-xylene mol-ecule located about an inversion center. The terminal penta-lene ring is envelope-flap disordered at the C atom farthest from the skeletal indole unit, with a refined occupancy ratio of 0.819 (4):0.181 (4). The major component has this C atom bent away from the spiro-fused cyclo-pentane ring. In the crystal, mol-ecules are connected by N-H⋯π inter-actions, forming chains along [100], and N-H⋯π and C-H⋯π inter-actions, forming chains along [001], which results in the formation of slabs parallel to (010).

  4. Crystal structure of (3S*,4R*)-4-fluoro-3-(4-meth-oxy-phen-yl)-1-oxo-2-phenyl-1,2,3,4-tetra-hydro-iso-quinoline-4-carb-oxy-lic acid.

    Science.gov (United States)

    Lehmann, Anna; Lechner, Lisa; Radacki, Krzysztof; Braunschweig, Holger; Holzgrabe, Ulrike

    2017-06-01

    The title compound, C23H18FNO4, crystallized as a racemate. It exhibits a cis conformation with respect to the F atom and the methine H atom. The piperidine ring has a screw-boat conformation. The meth-oxy-phenyl ring and the phenyl ring are inclined to the mean plane of the iso-quinoline ring system by 89.85 (4) and 46.62 (5)°, respectively, and by 78.15 (5)° to one another. In the crystal, mol-ecules are linked by an O-H⋯O hydrogen bond forming chains propagating along the a-axis direction. The chains are linked by C-H⋯F hydrogen bonds, forming layers lying parallel to the ab plane.

  5. Inulin crystal initiation via a glucose-fructose cross-link of adjacent polymer chains: atomic force microscopy and static molecular modelling.

    Science.gov (United States)

    Cooper, Peter D; Rajapaksha, K Harinda; Barclay, Thomas G; Ginic-Markovic, Milena; Gerson, Andrea R; Petrovsky, Nikolai

    2015-03-06

    Semi-crystalline microparticles of inulin (MPI) have clinical utility as potent human vaccine adjuvants but their relevant surface structure and crystal assembly remain undefined. We show inulin crystal surfaces to resemble multi-layered, discoid radial spherulites resulting from very rapid formation of complex tertiary structures, implying directed crystal initiation. Physical and in silico molecular modelling of unit cells confirm steric feasibility of initiation by hydrogen-bonded cross-linking of terminal glucose to a fructose of another chain, mimicking bonding in sucrose crystals. A strong, chelate-like dual H-bond is proposed to compel the known antiparallel alignment of inulin chains. Such cross-linking would require one extra fructose per chain in the native inulin crystal, as observed. Completion of five H-bonded internal ring-domains would 'lock in' each new 6-fructose structural unit of each antiparallel helix pair to create a new isoform. All known properties of inulin isoforms follow readily from these concepts.

  6. Crystal structure of rac-3-[2,3-bis-(phenyl-sulfan-yl)-3H-indol-3-yl]propanoic acid.

    Science.gov (United States)

    Noland, Wayland E; Brown, Christopher D; Bisel, Amanda M; Schneerer, Andrew K; Tritch, Kenneth J

    2015-11-01

    The title compound, C23H19NO2S2, was obtained as an unexpected regioisomer from an attempted synthesis of an inter-mediate for a substituent-effect study on ergot alkaloids. This is the first report of a 1H-indole mono-thio-ating at the 2- and 3-positions to give a 3H-indole. In the crystal, the acid H atom is twisted roughly 180° from the typical carb-oxy conformation and forms centrosymmetric O-H⋯N hydrogen-bonded dimers with the indole N atom of an inversion-related mol-ecule. Together with a weak C-H⋯O hydrogen bond involving the carbonyl O atom, chains are formed along [100].

  7. Crystal structure of dimethyl 2,5-bis-[(di-phen-oxy-phosphor-yl)-oxy]cyclo-hexa-1,4-diene-1,4-di-carboxyl-ate.

    Science.gov (United States)

    Gao, Lei; Ma, Zongshan; Yan, Hong

    2015-06-01

    In the title compound, C34H30O12P2, which was synthesized via the esterification of dimethyl 2,5-dioxo-1,4-cyclo-hexa-nedi-carboxyl-ate with diphenyl chloro-phosphate, the mol-ecule has crystallographic inversion symmetry. The dihedral angles between the plane of the cyclo-hexa-1,4-diene ring and those of the two benzene rings of the substituent phosphate groups are 41.0 (1) and 89.5 (1)°, while that with the ester group is 3.1 (3)°. In the crystal, only weak inter-molecular C-H⋯O hydrogen bonds are present.

  8. Crystal structure of 1-ferrocenyl-2-(4-methyl-benzo-yl)spiro-[11H-pyrrolidizine-3,11'-indeno[1,2-b]quinoxaline].

    Science.gov (United States)

    Chandralekha, Kuppan; Gavaskar, Deivasigamani; Sureshbabu, Adukamparai Rajukrishnan; Lakshmi, Srinivasakannan

    2014-09-01

    In the title compound, [Fe(C5H5)(C34H28N3O)], the four-fused-rings system of the 11H-indeno-[1,2-b]quinoxaline unit is approximately planar [maximum deviation = 0.167 (4) Å] and forms a dihedral angle of 37.25 (6)° with the plane of the benzene ring of the methyl-benzoyl group. Both pyrrolidine rings adopt a twist conformation. An intra-molecular C-H⋯O hydrogen bond is observed. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds and weak C-H⋯π inter-actions, forming double chains extending parallel to the c axis.

  9. Crystal structure of 4-{[(2,4-di-hydroxy-benzyl-idene)amino]-meth-yl}cyclo-hexane-carb-oxy-lic acid.

    Science.gov (United States)

    Danish, Muhammad; Akbar, Saba; Tahir, Muhammad Nawaz; Butt, Rabia Ayub; Ashfaq, Muhammad

    2015-12-01

    In the title compound, C15H19NO4, the cyclo-hexyl ring adopts a chair conformation with both exocyclic C-C bonds in equatorial orientations. The dihedral angle between the basal plane of cyclo-hexyl ring and the 2,4-di-hydroxy-benzaldehyde moiety is 84.13 (13)°. An intra-molecular O-H⋯N hydrogen bonds closes an S(6) ring. In the crystal, Oc-H⋯Op (c = carb-oxy-lic acid, p = phenol) hydrogen bonds link the mol-ecules into [100] C(13) chains whereas an Op-H⋯Oc hydrogen bond generates [101] C(15) chains. Together, these bonds generate (010) sheets incorporating R 2 (2)(20) loops. Weak C-H⋯O and C-H⋯π inter-actions also occur.

  10. Crystal structures of deuterated sodium molybdate dihydrate and sodium tungstate dihydrate from time-of-flight neutron powder diffraction.

    Science.gov (United States)

    Fortes, A Dominic

    2015-07-01

    Time-of-flight neutron powder diffraction data have been measured from ∼90 mol% deuterated isotopologues of Na2MoO4·2H2O and Na2WO4·2H2O at 295 K to a resolution of sin (θ)/λ = 0.77 Å(-1). The use of neutrons has allowed refinement of structural parameters with a precision that varies by a factor of two from the heaviest to the lightest atoms; this contrasts with the X-ray based refinements where precision may be > 20× poorer for O atoms in the presence of atoms such as Mo and W. The accuracy and precision of inter-atomic distances and angles are in excellent agreement with recent X-ray single-crystal structure refinements whilst also completing our view of the hydrogen-bond geometry to the same degree of statistical certainty. The two structures are isotypic, space-group Pbca, with all atoms occupying general positions, being comprised of edge- and corner-sharing NaO5 and NaO6 polyhedra that form layers parallel with (010) inter-leaved with planes of XO4 (X = Mo, W) tetra-hedra that are linked by chains of water mol-ecules along [100] and [001]. The complete structure is identical with the previously described molybdate [Capitelli et al. (2006 ▸). Asian J. Chem. 18, 2856-2860] but shows that the purported three-centred inter-action involving one of the water mol-ecules in the tungstate [Farrugia (2007 ▸). Acta Cryst. E63, i142] is in fact an ordinary two-centred 'linear' hydrogen bond.

  11. Crystal structures of a copper(II) and the isotypic nickel(II) and palladium(II) complexes of the ligand (E)-1-[(2,4,6-tri-bromo-phen-yl)diazen-yl]naphthalen-2-ol.

    Science.gov (United States)

    Chetioui, Souheyla; Rouag, Djamil-Azzeddine; Djukic, Jean-Pierre; Bochet, Christian G; Touzani, Rachid; Bailly, Corinne; Crochet, Aurélien; Fromm, Katharina M

    2016-08-01

    In the copper(II) complex, bis-{(E)-1-[(2,4,6-tri-bromo-phen-yl)diazen-yl]naph-thalen-2-olato}copper(II), [Cu(C16H8Br3N2O)2], (I), the metal cation is coord-inated by two N atoms and two O atoms from two bidentate (E)-1-[(2,4,6-tri-bromo-phen-yl)diazen-yl]naphthalen-2-olate ligands, forming a slightly distorted square-planar environment. In one of the ligands, the tri-bromo-benzene ring is inclined to the naphthalene ring system by 37.4 (5)°, creating a weak intra-molecular Cu⋯Br inter-action [3.134 (2) Å], while in the other ligand, the tri-bromo-benzene ring is inclined to the naphthalene ring system by 72.1 (6)°. In the isotypic nickel(II) and palladium(II) complexes, namely bis-{(E)-1-[(2,4,6-tri-bromo-phen-yl)diazen-yl]naphthalen-2-olato}nickel(II), [Ni(C16H8Br3N2O)2], (II), and bis-{(E)-1-[(2,4,6-tri-bromo-phen-yl)diazen-yl]naphthalen-2-olato}palladium(II), [Pd(C16H8Br3N2O)2], (III), respectively, the metal atoms are located on centres of inversion, hence the metal coordination spheres have perfect square-planar geometries. The tri-bromo-benzene rings are inclined to the naphthalene ring systems by 80.79 (18)° in (II) and by 80.8 (3)° in (III). In the crystal of (I), mol-ecules are linked by C-H⋯Br hydrogen bonds, forming chains along [010]. The chains are linked by C-H⋯π inter-actions, forming sheets parallel to (011). In the crystals of (II) and (III), mol-ecules are linked by C-H⋯π inter-actions, forming slabs parallel to (10-1). For the copper(II) complex (I), a region of disordered electron density was corrected for using the SQUEEZE routine in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9-18]. The formula mass and unit-cell characteristics of the disordered solvent mol-ecules were not taken into account during refinement.

  12. N-(3-Chloro-4-methyl-phen-yl)succinamic acid.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-03-01

    In the crystal structure of the title compound, C(11)H(12)ClNO(3), the asymmetric unit contains two independent mol-ecules. The N-H bond in the amide segment is anti to the meta-Cl atom in the benzene ring, in both molecules. The amide and carboxyl C=O bonds are also anti to each other and anti to the H atoms on the adjacent -CH(2) groups. Furthermore, the C=O and O-H bonds of the acid group are in syn positions with respect to each other. The dihedral angles between the benzene ring and the amide group are 40.6 (2) and 44.9 (3)° in the two independent molecules. In the crystal, mol-ecules are packed into sheets parallel to the (11-3) plane through O-H⋯O and N-H⋯O hydrogen bonds.

  13. N-(4-Methyl-benzo-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Suchetan, P A; Foro, Sabine; Gowda, B Thimme

    2012-03-01

    The asymmetric unit of the title compound, C(14)H(12)N(2)O(5)S, contains two independent mol-ecules. The dihedral angles between the aromatic rings are 82.03 (9) and 79.47 (8)° in the two independent mol-ecules. In the crystal, the two mol-ecules in the asymmetric unit are linked into dimers via pairs of N-H⋯O(S) hydrogen bonds to generate C(4) chains.

  14. Crystal structure of hexa-aqua-nickel(II) bis-{5-bromo-7-[(2-hy-droxy-eth-yl)amino]-1-methyl-6-oxido-quinolin-1-ium-3-sulfonate} monohydrate.

    Science.gov (United States)

    Le Thi Hong, Hai; Nguyen Thi Ngoc, Vinh; Do Thi Van, Anh; Van Meervelt, Luc

    2016-09-01

    The asymmetric unit of the title compound, [Ni(H2O)6](C12H12BrN2O5S)2·H2O, contains a half hexa-aqua-nickel(II) complex cation with the Ni(II) ion lying on an inversion center, one 5-bromo-7-[(2-hy-droxy-eth-yl)amino]-1-methyl-6-oxido-quinolin-1-ium-3-sulfonate (QAO) anion and a half lattice water mol-ecule on a twofold rotation axis. In the crystal, QAO anions are stacked in a column along the c axis by π-π stacking inter-actions [centroid-centroid distances 3.5922 (10)-3.7223 (11) Å]. The columns are inter-linked by hexa-aqua-nickel(II) cations through O-H⋯O and N-H⋯O hydrogen bonds.

  15. 2-({[(Pyridin-1-ium-2-ylmeth-yl)carbamo-yl]form-amido}-meth-yl)pyridin-1-ium bis-(3,5-di-carb-oxy-benzoate): crystal structure and Hirshfeld surface analysis.

    Science.gov (United States)

    Jotani, Mukesh M; Syed, Sabrina; Halim, Siti Nadiah Abdul; Tiekink, Edward R T

    2016-02-01

    The asymmetric unit of the title salt, C14H16N4O2 (2+)·2C9H5O6 (-), comprises half a dication, being located about a centre of inversion, and one anion, in a general position. The central C4N2O2 group of atoms in the dication are almost planar (r.m.s. deviation = 0.009 Å), and the carbonyl groups lie in an anti disposition to enable the formation of intra-molecular amide-N-H⋯O(carbon-yl) hydrogen bonds. To a first approximation, the pyridinium and amide N atoms lie to the same side of the mol-ecule [Npy-C-C-Namide torsion angle = 34.8 (2)°], and the anti pyridinium rings are approximately perpendicular to the central part of the mol-ecule [dihedral angle = 68.21 (8)°]. In the anion, one carboxyl-ate group is almost coplanar with the ring to which it is connected [Cben-Cben-Cq-O torsion angle = 2.0 (3)°], whereas the other carboxyl-ate and carb-oxy-lic acid groups are twisted out of the plane [torsion angles = 16.4 (3) and 15.3 (3)°, respectively]. In the crystal, anions assemble into layers parallel to (10-4) via hy-droxy-O-H⋯O(carbon-yl) and charge-assisted hy-droxy-O-H⋯O(carboxyl-ate) hydrogen bonds. The dications are linked into supra-molecular tapes by amide-N-H⋯O(amide) hydrogen bonds, and thread through the voids in the anionic layers, being connected by charge-assisted pyridinium-N-O(carboxyl-ate) hydrogen bonds, so that a three-dimensional architecture ensues. An analysis of the Hirshfeld surface points to the importance of O-H⋯O hydrogen bonding in the crystal structure.

  16. Crystal structure of an unknown solvate of (piperazine-κN){5,10,15,20-tetra-kis-[4-(benzo-yloxy)phen-yl]porphyrinato-κ(4) N}zinc.

    Science.gov (United States)

    Nasri, Soumaya; Ezzayani, Khaireddine; Turowska-Tyrk, Ilona; Roisnel, Thierry; Nasri, Habib

    2016-07-01

    The title compound, [Zn(C72H44N4O8)(C4H10N2)] or [Zn(TPBP)(pipz] (where TPBP and pipz are 5,10,15,20-tetra-kis-[4-(benzo-yloxy)phen-yl]porphyrinato and piperazine ligands respectively), features a distorted square-pyramidal coordin-ation geometry about the central Zn(II) atom. This central atom is chelated by the four N atoms of the porphyrinate anion and further coordinated by a nitro-gen atom of the piperazine axial ligand, which adopts a chair confirmation. The average Zn-N(pyrrole) bond length is 2.078 (7) Å and the Zn- N(pipz) bond length is 2.1274 (19) Å. The zinc cation is displaced by 0.4365 (4) Å from the N4C20 mean plane of the porphyrinate anion toward the piperazine axial ligand. This porphyrinate macrocycle exhibits major saddle and moderate ruffling deformations. In the crystal, the supra-molecular structure is made by parallel pairs of layers along (100), with an inter-layer distance of 4.100 Å while the distance between two pairs of layers is 4.047 Å. A region of electron density was treated with the SQUEEZE [Spek (2015 ▸). Acta Cryst. C71, 9-18] procedure in PLATON following unsuccessful attempts to model it as being part of disordered n-hexane solvent and water mol-ecules. The given chemical formula and other crystal data do not take into account these solvent mol-ecules.

  17. 4-Chloro-N-(3-methyl-benzo-yl)benzene-sulfonamide monohydrate.

    Science.gov (United States)

    Suchetan, P A; Foro, Sabine; Gowda, B Thimme; Prakash, M Shet

    2012-01-01

    In the title compound, C(14)H(12)ClNO(3)S·H(2)O, the dihedral angle between the sulfonyl and benzoyl benzene rings is 84.4 (2)°. In the crystal, every water mol-ecule forms four hydrogen bonds with three different mol-ecules of 4-chloro-N-(3-methyl-benzo-yl)benzene-sulfonamide. One of the water H atoms forms a bifurcated hydrogen bond with both the sulfonyl and the carbonyl O atoms of the same mol-ecule. Mol-ecules are linked into layers in the ab plane through N-H⋯O and O-H⋯O hydrogen bonds.

  18. catena-Poly[[triaqua-chlorido-μ(3)-malonato-cerium(III)] hemihydrate].

    Science.gov (United States)

    Silva, Patrícia; Fernandes, José A; Almeida Paz, Filipe A

    2010-11-06

    The asymmetric unit of the title compound, {[Ce(C(3)H(2)O(4))Cl(H(2)O)(3)]·0.5H(2)O}(n), contains a Ce(3+) atom coordinated by a chloride anion, three water mol-ecules and a malonate ligand, and one water mol-ecule of crystallization with a factor of occupancy of 50%. The malonate ligand is bonded to three different symmetry-related metal atoms yielding a one-dimensional coordination polymer running parallel to the a axis. A supra-molecular network composed of strong and highly directional O-H⋯O and O-H⋯Cl hydrogen bonds ensures a close and effective packing of adjacent polymeric chains.

  19. catena-Poly[[tri-aqua-copper(II)]-μ-5-carb-oxy-benzene-1,3-di-carboxyl-ato-κ(2) O (1):O (3)].

    Science.gov (United States)

    Ma, Yu-Hong; Ma, Pi-Zhuang; Yao, Ting; Hao, Jing-Tuan

    2013-01-01

    In the title complex, [Cu(C9H4O6)(H2O)3] n , the Cu(II) cation exhibits a distorted square-pyramidal coordination geometry involving five O atoms from two monodentate 5-carb-oxy-benzene-1,3-di-carboxyl-ate anions and three water mol-ecules. The 5-carb-oxy-benzene-1,3-di-carboxyl-ate anions bridge Cu(II) cations into zigzag polymeric chains running along the b-axis direction. These chains are further linked by O-H⋯O hydrogen bonds between coordinating water mol-ecules or carboxyl groups and carboxylate groups into a three-dimensional supra-molecular architecture. In the crystal, π-π stacking is observed between parallel benzene rings of adjacent chains, the centroid-centroid distances being 3.584 (3) and 3.684 (3) Å.

  20. Crystal structures of two substituted thia-zolidine derivatives.

    Science.gov (United States)

    Viswanathan, Vijayan; Rao, Naga Siva; Raghunathan, Raghavachary; Velmurugan, Devadasan

    2016-08-01

    In the first of the compounds reported herein, namely 6'-ferrocenyl-6a'-nitro-6',6a',6b',7',9',11a'-hexa-hydro-2H-spiro-[ace-naphthyl-ene-1,11'-chromeno[3',4':3,4]pyrrolo-[1,2-c]thia-zol]-2-one, [Fe(C5H5)(C29H21N2O4S)], (I), the thia-zolidine ring adopts a twist conformation on the methine N-C atoms. In the second compound, viz. 6'-(4-methoxy-phen-yl)-6a'-nitro-6',6a',6b',7',9',11a'-hexa-hydro-2H-spiro-[ace-naphthyl-ene-1,11'-chromeno[3',4':3,4]pyrrolo-[1,2-c]thia-zol]-2-one, [Fe(C5H5)(C26H19N2O5S)], (II), the thia-zolidine ring adopts an envelope conformation with a methine C atom as the flap. In both compounds, the pyrrolidine ring adopts a twist conformation on the thia-zolidine and tetra-hydro-pyran C atoms. The mean planes of the thia-zolidine and pyrrolidine rings subtend angles of 67.30 (1) and 62.95 (7)° in (I) and (II), respectively, while the mean plane of the pyrrolidine ring makes dihedral angles of 76.53 (1) and 87.74 (7)° with the ace-naphthyl-ene ring system in (I) and (II), respectively. In both compounds, an intra-molecular C-H⋯O hydrogen bond forms an S(7) ring motif. In the crystal of (I), mol-ecules are linked via two different C-H⋯O hydrogen bonds, forming chains along [001] and [100]. In (II), they are linked through C-H⋯O hydrogen bonds, forming dimers with an R 2 (2)(10) ring motif while C-H⋯π inter-actions link the mol-ecules in a head-to-tail fashion, forming chains along the a-axis direction.

  1. Adjacent segment disease.

    Science.gov (United States)

    Virk, Sohrab S; Niedermeier, Steven; Yu, Elizabeth; Khan, Safdar N

    2014-08-01

    EDUCATIONAL OBJECTIVES As a result of reading this article, physicians should be able to: 1. Understand the forces that predispose adjacent cervical segments to degeneration. 2. Understand the challenges of radiographic evaluation in the diagnosis of cervical and lumbar adjacent segment disease. 3. Describe the changes in biomechanical forces applied to adjacent segments of lumbar vertebrae with fusion. 4. Know the risk factors for adjacent segment disease in spinal fusion. Adjacent segment disease (ASD) is a broad term encompassing many complications of spinal fusion, including listhesis, instability, herniated nucleus pulposus, stenosis, hypertrophic facet arthritis, scoliosis, and vertebral compression fracture. The area of the cervical spine where most fusions occur (C3-C7) is adjacent to a highly mobile upper cervical region, and this contributes to the biomechanical stress put on the adjacent cervical segments postfusion. Studies have shown that after fusion surgery, there is increased load on adjacent segments. Definitive treatment of ASD is a topic of continuing research, but in general, treatment choices are dictated by patient age and degree of debilitation. Investigators have also studied the risk factors associated with spinal fusion that may predispose certain patients to ASD postfusion, and these data are invaluable for properly counseling patients considering spinal fusion surgery. Biomechanical studies have confirmed the added stress on adjacent segments in the cervical and lumbar spine. The diagnosis of cervical ASD is complicated given the imprecise correlation of radiographic and clinical findings. Although radiological and clinical diagnoses do not always correlate, radiographs and clinical examination dictate how a patient with prolonged pain is treated. Options for both cervical and lumbar spine ASD include fusion and/or decompression. Current studies are encouraging regarding the adoption of arthroplasty in spinal surgery, but more long

  2. Crystal structure of racemic [(1R,2S,3R,4S,6S)-2,6-bis-(furan-2-yl)-4-hy-droxy-4-(thio-phen-2-yl)cyclo-hexane-1,3-di-yl]bis-(thio-phen-2-yl-methanone).

    Science.gov (United States)

    Çelik, Ísmail; Ersanlı, Cem Cüneyt; Akkurt, Mehmet; Gezegen, Hayrettin; Köseoğlu, Rahmi

    2016-07-01

    In the title compound, C28H22O5S3, the central cyclo-hexane ring adopts a chair conformation. The atoms of the furan ring attached to the 6-position of the central cyclo-hexane ring are disordered over two sets of sites with occupancies of 0.832 (5) and 0.168 (5). The hy-droxy group is disordered over two positions (at the 4- and 6-positions of the cyclo-hexane ring) in the ratio 0.832 (5):0.168 (5). In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming layers parallel to (100).

  3. cyclo-Tetra-μ-malato-κO,O',O'':O'''-tetra-kis[bis-(1H-benzimidazole-κN)cobalt(II)] eicosa-hydrate.

    Science.gov (United States)

    Li, Jun-Hua; Nie, Jing-Jing; Su, Jian-Rong; Xu, Duan-Jun

    2008-03-14

    The title compound, [Co(4)(C(4)H(4)O(5))(4)(C(7)H(6)N(2))(8)]·20H(2)O, consists of tetra-nuclear Co(II) complexes and disordered uncoordinated water mol-ecules. The tetra-meric complex mol-ecule has symmetry. While two benzimidazole mol-ecules and a tridentate malate dianion coordinate a Co(II) ion, the carboxylate O atom from an adjacent malate dianion bridges the Co(II) ions to complete a distorted octa-hedral coordination geometry. The tridentate malate dianion chelates the Co(II) ion, and the chelate six- and five-membered rings show half-chair and envelope configurations, respectively. A face-to-face separation of 3.494 (9) Å between parallel benzimidazole ligands indicates the existence of π-π stacking between adjacent complexes. The crystal structure also involves N-H⋯O and O-H⋯O hydrogen bonds.

  4. N-(2-Chloro-benzo-yl)-3-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Suchetan, P A; Foro, Sabine; Gowda, B Thimme

    2012-02-01

    In the mol-ecule of the title compound, C(13)H(9)ClN(2)O(5)S, the dihedral angle between the two aromatic rings is 84.3 (1)°. In the crystal, mol-ecules are linked into chains via N-H⋯O(S) hydrogen bonds.

  5. Crystal structures of the two epimers from the unusual thermal C6-epimerization of 5-oxo-1,2,3,5,5a,6,7,9b-octa-hydro-7,9a-ep-oxy-pyrrolo-[2,1-a]iso-indole-6-carb-oxy-lic acid, 5a(RS),6(SR),7(RS),9a(SR),9b(SR) and 5a(RS),6(RS),7(RS),9a(SR),9b(SR).

    Science.gov (United States)

    Poplevin, Dmitry S; Zubkov, Fedor I; Dorovatovskii, Pavel V; Zubavichus, Yan V; Khrustalev, Victor N

    2016-10-01

    The isomeric title compounds, C12H13NO4 (Ia) and C12H13NO4 (IIa), the products of an usual thermal C6-epimerization of 5-oxo-1,2,3,5,5a,6,7,9b-octa-hydro-7,9a-ep-oxy-pyrrolo-[2,1-a]iso-indole-6-carb-oxy-lic acid, represent the two different diastereomers and have very similar mol-ecular geometries. The mol-ecules of both compounds comprise a fused tetra-cyclic system containing four five-membered rings (pyrrolidine, pyrrolidinone, di-hydro-furan and tetra-hydro-furan), all of which adopt the usual envelope conformations. The dihedral angle between the basal planes of the pyrrolidine and pyrrolidinone rings are 14.3 (2) and 16.50 (11)°, respectively, for (Ia) and (IIa). The nitro-gen atom has a slightly pyramidalized geometry [bond-angle sum = 355.9 and 355.3°, for (Ia) and (IIa)], respectively. In the crystal of (Ia), mol-ecules form zigzag-like hydrogen-bonded chains along [010] through strong O-H⋯O hydrogen bonds and are further linked by weak C-H⋯O hydrogen bonds into complex two-tier layers parallel to (100). Unlike (Ia), the crystal of (IIa) contains centrosymmetric cyclic hydrogen-bonded dimers [graph set R(2)2(14)], formed through strong O-H⋯O hydrogen bonds and are further linked by weak C-H⋯O hydrogen bonds into ribbons extending across [101].

  6. N-(2-Chloro-phen-yl)-N'-(2-methyl-phen-yl)succinamide.

    Science.gov (United States)

    Saraswathi, B S; Foro, Sabine; Gowda, B Thimme

    2011-10-01

    In the title compound, C(17)H(17)ClN(2)O(2), the asymmetric unit contains half a mol-ecule with a centre of symmetry at the mid-point of the central C-C bond. The conformations of the amide O atoms are anti to the methyl-ene atoms. Further, the N-H bonds in the amide fragments are anti to the ortho-chloro/methyl groups in the adjacent benzene rings. The dihedral angle between the benzene ring and the NH-C(O)-CH(2) segment in the two halves of the mol-ecule is 62.0 (2)°. In the crystal, a series of N-H⋯O inter-molecular hydrogen bonds link the mol-ecules into column-like infinite chains along the a axis. The methyl and Cl groups are disordered with respect to the ortho positions of the benzene ring, with site-occupation factors of 0.5 each.

  7. 2,2'-(Propane-1,3-di-yl)bis-(2H-indazole).

    Science.gov (United States)

    Ovalle, Saúl; Bernès, Sylvain; Pérez Rodríguez, Nancy; Elizondo Martínez, Perla

    2011-08-01

    The title mol-ecule, C(17)H(16)N(4), is a bis-indazole crystallized in the rare 2H-tautomeric form. Indazole heterocycles are connected by a propane C(3) chain, and the mol-ecule is placed on a general position, in contrast to the analogous compound with a central C(2) ethane bridge, which was previously found to be placed on an inversion center in the same space group. In the title mol-ecule, indazole rings make a dihedral angle of 60.11 (7)°, and the bridging alkyl chain displays a trans conformation, resulting in a W-shaped mol-ecule. In the crystal, mol-ecules inter-act weakly through π-π contacts between inversion-related pyrazole rings, with a centroid-centroid separation of 3.746 (2) Å.

  8. Crystal structures of two mixed-valence copper cyanide complexes with N-methyl-ethylenedi-amine.

    Science.gov (United States)

    Corfield, Peter W R; Sabatino, Alexander

    2017-02-01

    The crystal structures of two mixed-valence copper cyanide compounds involving N-methyl-ethylenedi-amine (meen), are described. In compound (I), poly[bis(μ3-cyanido-κ3C:C:N)tris(μ2-cyanido-κ2C:N)bis(N-methylethane-1,2-di-amine-κ2N,N')tricopper(I)copper(II)], [Cu4(CN)5(C3H10N2)2] or Cu4(CN)5meen2, cyanide groups link Cu(I) atoms into a three-dimensional network containing open channels parallel to the b axis. In the network, two tetra-hedrally bound Cu(I) atoms are bonded by the C atoms of two end-on bridging CN groups to form Cu2(CN)6 moieties with the Cu atoms in close contact at 2.560 (1) Å. Other trigonally bound Cu(I) atoms link these units together to form the network. The Cu(II) atoms, coordinated by two meen units, are covalently linked to the network via a cyanide bridge, and project into the open network channels. In the mol-ecular compound (II), [(N-methylethylenediamine-κ(2)N,N')copper(II)]-μ(2)-cyanido-κ(2)C:N-[bis(cyanido-κC)copper(I)] monohydrate, [Cu2(CN)3(C3H10N2)2]·H2O or Cu2(CN)3meen2·H2O, a CN group connects a Cu(II) atom coordinated by two meen groups with a trigonal-planar Cu(I) atom coordinated by CN groups. The mol-ecules are linked into centrosymmetric dimers via hydrogen bonds to two water mol-ecules. In both compounds, the bridging cyanide between the Cu(II) and Cu(I) atoms has the N atom bonded to Cu(II) and the C atom bonded to Cu(I), and the Cu(II) atoms are in a square-pyramidal coordination.

  9. N-(2,3-Dimethyl-phen-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-11-01

    There are two independent mol-ecules in the asymmetric unit of the title compound, C(14)H(14)N(2)O(4)S. The N-H bonds are syn to the ortho-nitro groups in the sulfonyl benzene rings and anti to the methyl groups in the aniline benzene rings. The mol-ecules are twisted at the S-N bonds with torsion angles of -60.4 (3) and 58.8 (3)° in the two mol-ecules. The dihedral angles between the planes of the sulfonyl and the anilino benzene rings are 53.67 (8) and 56.99 (9)°. The amide H atoms of both mol-ecules are involved in an intra-molecular hydrogen bond, generating an S(7) motif. In the crystal, pairs of N-H⋯O(S) hydrogen bonds link like mol-ecules into inversion dimers.

  10. 3-Acetyl-1-(4-methyl-phen-yl)thio-urea.

    Science.gov (United States)

    Gowda, B Thimme; Foro, Sabine; Kumar, Sharatha

    2012-07-01

    The asymmetric unit of the title compound, C(10)H(12)N(2)OS, contains two independent mol-ecules. In both mol-ecules, the conformations of the two N-H bonds are anti to each other. Furthermore, the conformations of the amide C=S bonds and the C=O bonds are anti to each other. The dihedral angles between the benzene ring and the side chain are 52.8 (1) and 68.0 (1)° in the two independent mol-ecules. An intra-molecular N-H⋯O hydrogen bond occurs in both independent mol-ecules. In the crystal, mol-ecules are linked into infinite chains along the a axis through a series of N-H⋯O and N-H⋯S hydrogen bonds.

  11. Crystal structure of 7-iodo-4-oxo-4H-chromene-3-carbaldehyde.

    Science.gov (United States)

    Ishikawa, Yoshinobu

    2016-12-01

    In the title compound, C10H5IO3, an iodinated 3-formyl-chromone derivative, the non-H atoms are essentially coplanar (r.m.s. deviation = 0.0344 Å), with the largest deviation from the least-squares plane [0.101 (3) Å] being found for the formyl O atom. In the crystal, mol-ecules are linked through stacking inter-actions [centroid-centroid distance between the benzene rings = 3.700 (3) Å] and C-H⋯O hydrogen bonds. Halogen bonds between the I atoms at 7-position and the formyl O atoms [I1⋯O3 = 3.056 (2) Å, C6-I1⋯O3 = 173.18 (8)° and I1⋯O3-C10 = 111.12 (18)°] are also formed along [110], resulting in sheets perpendicular to the c axis, constructed by C-H⋯O hydrogen bonds and I⋯O halogen bonds.

  12. Crystal structure of γ-methyl l-glutamate N-carb-oxy anhydride.

    Science.gov (United States)

    Kanazawa, Hitoshi; Inada, Aya; Sakon, Aya; Uekusa, Hidehiro

    2015-01-01

    In the title compound, C7H9NO5, alternative name N-carb-oxy-l-glutamic anhydride γ-methyl ester, the oxazolidine ring is essentially planar with a maximum deviation of 0.020 (3) Å. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds between the imino group and the carbonyl O atom in the methyl ester group, forming a tape structure along the a-axis direction. The tapes are linked by C-H⋯O inter-actions into a sheet parallel to the ac plane. The tapes are also stacked along the b axis with short contacts between the oxazolidine rings [C⋯O contact distances = 2.808 (4)-3.060 (4) Å], so that the oxazolidine rings are arranged in a layer parallel to the ab plane. This arrangement of the oxazolidine rings is very preferable for the polymerization of the title compound in the solid state.

  13. Crystal structure of 4-oxo-4H-chromene-3-carb-oxy-lic acid.

    Science.gov (United States)

    Ishikawa, Yoshinobu

    2015-08-01

    In the title compound, C10H6O4, also known as 3-carb-oxy-chromone, the non-H atoms of the chromone ring are essentially coplanar (r.m.s. deviation = 0.0057 Å), with the maximum deviation from their least-squares plane [0.011 (2) Å] being for a pyran C atom. The dihedral angle between the fused ring and plane of the carb-oxy group is 3.06 (2)°. An intra-molecular hydrogen bond is formed between the ring carbonyl O atom and the carb-oxy O-H atom, closing an S(6) loop. In the crystal, mol-ecules are assembled by stacking inter-actions [centroid-centroid distance between the benzene and pyran rings = 3.844 (3) Å] and C-H⋯O hydrogen bonds, generating a three-dimensional network. Short contacts are also observed between the carb-oxy O and C atoms [C=O⋯C=O = 3.002 (3) Å].

  14. Crystal structure of a photobiologically active brominated angular pyran-ocoumarin: bromo-hy-droxy-seselin.

    Science.gov (United States)

    Bauri, A K; Foro, Sabine; Rahman, A F M Mustafizur

    2017-03-01

    The title compound, C14H13BrO3 [systematic name: rac-(9S,10R)-9-bromo-10-hy-droxy-8,8-dimethyl-9,10-di-hydro-2H,8H-pyrano[2,3-f]chromen-2-one], is a substituted pyran-ocoumarin, obtained by bromination of seselin [8,8-dimethyl-2H,8H-pyrano[2,3-f]chromen-2-one], which was isolated from the Indian herb Trachyspermum stictocarpum (Aajmod). The pyrano ring has a distorted half-chair conformation and its mean plane is inclined to the coumarin mean plane by 1.6 (2)°. In the crystal, mol-ecules are linked by pairs of O-H⋯O hydrogen bonds, forming inversion dimers with an R(2)2(16) ring motif. The dimers stack along the a-axis direction and are linked by offset π-π inter-actions, forming columns [inter-centroid distance = 3.514 (4) Å].

  15. Crystal structure of tri-hydrogen bis-{[1,1,1-tris-(2-oxido-ethyl-amino-meth-yl)ethane]-cobalt(III)} trinitrate.

    Science.gov (United States)

    Sethi, Waqas; Johannesen, Heini V; Morsing, Thorbjørn J; Piligkos, Stergios; Weihe, Høgni

    2015-12-01

    The title compound, [Co2(L)2](3+)·3NO3 (-) [where L = CH3C(CH2NHCH2CH2OH1/2)3], has been synthesized from the ligand 1,1,1-tris-(2-hy-droxy-ethyl-amino-meth-yl)ethane. The cobalt(III) dimer has an inter-esting and uncommon O-H⋯O hydrogen-bonding motif with the three bridging hy-droxy H atoms each being equally disordered over two positions. In the dimeric trication, the octa-hedrally coordinated Co(III) atoms and the capping C atoms lie on a threefold rotation axis. The N atoms of two crystallographically independent nitrate anions also lie on threefold rotation axes. N-H⋯O hydrogen bonding between the complex cations and nitrate anions leads to the formation of a three-dimensional network structure. The compound is a racemic conglomerate of crystals containing either d or l mol-ecules. The crystal used for this study is a d crystal.

  16. Crystal structure of bis-{(S)-1-[2-(di-phenyl-phosphan-yl)ferrocen-yl]-(R)-eth-yl}ammonium bromide di-chloro-methane monosolvate.

    Science.gov (United States)

    Zirakzadeh, Afrooz; Stöger, Berthold; Kirchner, Karl

    2017-02-01

    During the synthesis of an FeBr2 complex with the PNP ligand (R,R,SFc,SFc)-[Fe2(C5H5)2(C38H35NP2)] (1), single crystals of the di-chloro-methane monosolvate of the Br(-) salt of the protonated ligand 1H(+) were obtained serendipitously, i.e. [Fe2(C5H5)2(C38H36NP2)]Br·CH2Cl2. The crystal structure of 1H·Br·CH2Cl2 was determined by single-crystal X-ray diffraction. The mean bond lengths in the ferrocene units are Fe-C = 2.049 (3) Å and C-C = 1.422 (4) Å within the cyclo-penta-dienyl rings. The mean C-N bond length is 1.523 (4) Å. The inter-planar angle between the two connected cyclo-penta-dienyl rings is 49.2 (2)°. One ferrocene moiety adopts a staggered conformation, whereas the other is between staggered and eclipsed. The Br(-) ions and the CH2Cl2 mol-ecules are located in channels extending along . One ammonium H atom forms a hydrogen bond with the Br(-) ion [H⋯Br = 2.32 (4) Å and C-H⋯Br = 172 (3)°]. The second ammonium H atom is not involved in hydrogen bonding.

  17. N-(2-Chloro-benzo-yl)-4-methyl-benzene-sulfonamide.

    Science.gov (United States)

    Suchetan, P A; Foro, Sabine; Gowda, B Thimme

    2012-05-01

    In the title compound, C(14)H(12)ClNO(3)S, the C=O bond is syn to the Cl substituent in the adjacent benzene ring. The C-S-N-C torsion angle is -80.6 (6)°. The chloro-benzoyl ring is disordered and was refined using a split model [occupancy ratio 0.537 (3):0.463 (3)]. In the crystal, mol-ecules are linked by pairs of N-H⋯O(S) hydrogen bonds, forming inversion dimers.

  18. Crystal structure of [(1,2,3,4,11,12-η)-anthracene]tris-(tri-methyl-stann-yl)cobalt(III).

    Science.gov (United States)

    Brennessel, William W; Ellis, John E

    2014-11-01

    The asymmetric unit of the title structure, [Co(η(6)-C14H10){Sn(CH3)3}3], contains two independent mol-ecules. Each anthracene ligand is η(6)-coordinating to a Co(III) cation and is nearly planar [fold angles of 5.4 (3) and 9.7 (3)°], as would be expected for its behaving almost entirely as a donor to a high-oxidation-state metal center. The slight fold in each anthracene ligand gives rise to slightly longer Co-C bond lengths to the ring junction carbon atoms than to the other four. Each Co(III) cation is further coordinated by three Sn(CH3)3 ligands, giving each mol-ecule a three-legged piano-stool geometry. In each of the two independent mol-ecules, the trio of SnMe3 ligands are modeled as disordered over two positions, rotated by approximately 30%, such that the C atoms nearly overlap. In one mol-ecule, the disorder ratio refined to 0.9365 (8):0.0635 (8), while that for the other refined to 0.9686 (8):0.0314 (8). The mol-ecules are well separated, and thus no significant inter-molecular inter-actions are observed. The compound is of inter-est as the first structure report of an η(6)-anthracene cobalt(III) complex.

  19. N-(4-Chloro-3-methyl-phen-yl)succinamic acid.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-07-01

    The title compound, C(11)H(12)ClNO(3), crystallizes with two independent mol-ecules in the asymmetric unit in which the dihedral angles between the benzene ring and the amide group are 55.0 (2) and 28.2 (3)°. The two independent mol-ecules are linked by an N-H⋯O hydrogen bond. In the crystal, mol-ecules form inversion dimers via pairs of O-H⋯O hydrogen bonds. These dimers are linked into sheets parallel to (11-3) via N-H⋯O hydrogen bonds.

  20. Crystal structure of 1-(8-meth-oxy-2H-chromen-3-yl)ethanone.

    Science.gov (United States)

    Koh, Dongsoo

    2014-09-01

    In the structure of the title compound, C12H12O3, the di-hydro-pyran ring is fused with the benzene ring. The di-hydro-pyran ring is in a half-chair conformation, with the ring O and methyl-ene C atoms positioned 1.367 (3) and 1.504 (4) Å, respectively, on either side of the mean plane formed by the other four atoms. The meth-oxy group is coplanar with the benzene ring to which it is connected [Cb-Cb-Om-Cm torsion angle = -0.2 (4)°; b = benzene and m = meth-oxy], and similarly the aldehyde is coplanar with respect to the double bond of the di-hydro-pyran ring [Cdh-Cdh-Ca-Oa = -178.1 (3)°; dh = di-hydro-pyran and a = aldehyde]. In the crystal, mol-ecules are linked by weak meth-yl-meth-oxy C-H⋯O hydrogen bonds into supra-molecular chains along the a-axis direction.

  1. Crystal structure of 1H,1'H-[2,2'-biimid-azol]-3-ium hydrogen tartrate hemi-hydrate.

    Science.gov (United States)

    Gao, Xiao-Li; Bian, Li-Fang; Guo, Shao-Wei

    2014-11-01

    In the crystal of the title hydrated salt, C6H7N4 (+)·C4H5O6 (-)·0.5H2O, the bi-imidazole monocation, 1H,1'H-[2,2'-biimidazol]-3-ium, is hydrogen bonded, via N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonds, to the hydrogen tartrate anion and the water mol-ecule, which is located on a twofold rotation axis, forming sheets parallel to (001). The sheets are linked via C-H⋯O hydrogen bonds, forming a three-dimensional structure. There are also C=O⋯π inter-actions present [O⋯π distances are 3.00 (9) and 3.21 (7) Å], involving the carbonyl O atoms and the imidazolium ring, which may help to consolidate the structure. In the cation, the dihedral angle between the rings is 11.6 (2)°.

  2. Disorder of the dimeric TCNQ-TCNQ unit in the crystal structure of [Ni(bpy)3]2(TCNQ-TCNQ)(TCNQ)2·6H2O (TCNQ is 7,7,8,8-tetra-cyano-quinodi-methane).

    Science.gov (United States)

    Černák, Juraj; Kuchár, Juraj; Hegedüs, Michal

    2017-01-01

    Crystallization from an aqueous methanol system composed of Ni(NO3)2, 2,2'-bipyridine (bpy) and LiTCNQ (TCNQ is 7,7,8,8-tetra-cyano-quinodi-methane) in a 1:3:2 molar ratio yielded single crystals of bis-[tris-(2,2'-bi-pyridine-κ(2)N,N')nickel(II)] bis-(7,7,8,8-tetra-cyano-quinodi-methane radical anion) bi[7,7,8,8-tetra-cyano-quino-dimethanide] hexa-hydrate, [Ni(C10H8N2)3]2(C24H8N8)(C12H4N4)2·6H2O or [Ni(bpy)3]2(TCNQ-TCNQ)(TCNQ)2·6H2O. The crystal structure comprises [Ni(bpy)3](2+) complex cations, two centrosymmetric crystallographically independent TCNQ (·-) anion radicals with π-stacked exo groups, and an additional dimeric TCNQ-TCNQ unit which comprises 75.3 (9)% of a σ-dimerized (TCNQ-TCNQ)(2-) dianion and 24.7 (9)% of two TCNQ(·-) anion radicals with tightly π-stacked exo groups. The title complex represents the first example of an Ni(II) complex containing a σ-dimerized (TCNQ-TCNQ)(2-) dianion. Disordered solvent water mol-ecules present in the crystal structure participate in hydrogen-bonding inter-actions.

  3. Bis(2-hydroxy-benzaldehyde oxime) O,O'-butane-1,4-diyldicarbonyl ether.

    Science.gov (United States)

    Etemadi, Bijan; Kia, Reza; Sharghi, Hashem; Hosseini Sarvari, Mona

    2009-05-20

    The mol-ecule of the title compound, C(20)H(20)N(2)O(6), lies across a crystallographic inversion centre, the asymmetric unit comprising one half-mol-ecule. An intra-molecular O-H⋯N hydrogen bond generates a six-membered ring, producing an S(6) ring motif. Pairs of inter-molecular C-H⋯O hydrogen bonds link neighbouring mol-ecules into a layer with R(2) (2)(38) ring motif. The crystal structure is further stabilized by the inter-molecular C-H⋯π inter-actions.

  4. N-Benzoyl-4-nitro-benzene-sulfonamide monohydrate.

    Science.gov (United States)

    Suchetan, P A; Foro, Sabine; Gowda, B Thimme; Vidya, V M

    2012-01-01

    In the title compound, C(13)H(10)N(2)O(5)S·H(2)O, the dihedral angle between the sulfonyl and benzoyl benzene rings is 83.4 (1)°. In the crystal, the water mol-ecule forms four hydrogen bonds with three different mol-ecules of N-benzoyl-4-nitro-benzene-sulfonamide. One of the H atoms of H(2)O forms a bifurcated hydrogen bond with a sulfonyl and the carbonyl O atoms. Mol-ecules are linked into a three-dimensional network by N-H⋯O and O-H⋯O hydrogen bonds.

  5. 4-Chloro-N-(2,5-dimethyl-phen-yl)-2-methyl-benzene-sulfonamide.

    Science.gov (United States)

    Rodrigues, Vinola Z; Foro, Sabine; Gowda, B Thimme

    2011-11-01

    The asymmetric unit of the title compound, C(15)H(16)ClNO(2)S, contains three independent moleules. The conformation of the N-H bonds are anti to the ortho-methyl groups of the sulfonyl benzene rings in all the mol-ecules. The sulfonyl and the aniline benzene rings are tilted relative to each other by 43.0 (2), 37.0 (2) and by 46.0 (1)° in the three mol-ecules. In the crystal, inter-molecular N-H⋯O hydrogen bonds link each of the mol-ecules into centrosymmetric dimers.

  6. (E)-1-[2-Hy-droxy-4,6-bis-(meth-oxy-meth-oxy)phen-yl]-3-[3-meth-oxy-4-(meth-oxy-meth-oxy)phen-yl]prop-2-en-1-one.

    Science.gov (United States)

    Chang, Liu-Shuan; Li, Chen-Yang; Zhao, Yan-Mei; Xu, Fang; Gu, Zheng-Yi

    2011-11-01

    The title compound, C(22)H(26)O(9), crystallizes with two independent mol-ecules in the asymmetric unit in which the dihedral angles between the two benzene rings are 21.4 (2) and 5.1 (2)°. An intra-molecular O-H⋯O hydrogen bond occurs in each mol-ecule. Inter-molecular C-H⋯O hydrogen bonds stabilize the crystal structure.

  7. Crystal structure of bis-(2,2'-bi-pyridine)[N'-(quino-lin-2-ylmethylidene)pyridine-2-carbohydrazide]ruthenium(II) bis(tetra-fluorido-borate) di-chloro-methane tris-olvate.

    Science.gov (United States)

    Mori, Asami; Suzuki, Takayoshi; Nakajima, Kiyohiko

    2015-02-01

    The title compound, [Ru(C10H8N2)2(C16H12N4O)](BF4)2·3CH2Cl2, crystallizes with one complex dication, two BF4 (-) counter-anions and three di-chloro-methane solvent mol-ecules in the asymmetric unit. The central Ru(II) atom adopts a distorted octa-hedral coordination sphere with two 2,2'-bi-pyridine (bpy) and one quinoline-2-carbaldehyde (pyridine-2-carbon-yl)hydrazone (HL) ligand. The hydrazone ligand has a Z form and coordinates to the Ru(II) atom via the amide-O and imine-N atoms, affording a planar five-membered chelate ring, while its pyridine-N and quinoline-N donor atoms in the substituents are non-coordinating. The hydrazone N-H group forms an intra-molecular hydrogen bond with the quinoline-N atom. In the crystal, the quinoline moiety of HL shows the shortest π-π stacking inter-action with the pyridine substituent of HL in a neighbouring complex, the centroid-to-centroid distance being 3.793 (3) Å.

  8. Crystal structures of two ansa-titanocene tri-fluoro-methane-sulfonate complexes bearing the Me2Si(C5Me4)2 ligand.

    Science.gov (United States)

    Kessler, Monty; Godemann, Christian; Spannenberg, Anke; Beweries, Torsten

    2016-12-01

    The crystal structures of two ansa-titanocene tri-fluoro-methane-sulfonate complexes bearing the Me2Si(C5Me4)2 ligand are reported, namely [di-methylbis-(η(5)-tetra-methyl-cyclo-penta-dien-yl)silane](tri-fluoro-methane-sulfonato-κ(2)O,O')titanium(III) toluene monosolvate, [Ti(CF3O3S)(C20H30Si)]·C7H8, 1, and chlorido-[di-methyl-bis-(η(5)-tetra-methyl-cyclo-penta-dien-yl)silane](tri-fluoro-methane-sulfonato-κO)titanium(IV), [Ti(CF3O3S)(C20H30Si)Cl], 2. Both complexes display a bent metallocene unit, the metal atom being coordinated in a distorted tetra-hedral geometry, with the tri-fluoro-methane-sulfonate anion acting as a bidentate or monodentate ligand in 1 and 2, respectively. In 1, weak π-π stacking inter-actions involving the toluene solvent mol-ecules [centroid-to-centroid distance = 3.9491 (11) Å] are observed.

  9. Crystal structure of 3-(thio-phen-2-yl)-5-p-tolyl-4,5-di-hydro-1H-pyrazole-1-carbo-thio-amide.

    Science.gov (United States)

    Naveen, S; Pavithra, G; Abdoh, Muneer; Ajay Kumar, K; Warad, Ismail; Lokanath, N K

    2015-07-01

    In the title compound, C15H15N3S2, the central pyrazole ring adopts a twisted conformation on the -CH-CH2- bond. Its mean plane makes dihedral angles of 7.19 (12) and 71.13 (11)° with those of the thio-phene and toluene rings, respectively. The carbothi-amide group [C(=S)-N] is inclined to the pyrazole ring mean plane by 16.8 (2)°. In the crystal, mol-ecules are linked by N-H⋯S hydrogen bonds, forming chains propagating along [010]. Within the chains, there are N-H⋯π inter-actions present. Between the chains there are weak parallel slipped π-π inter-actions involving inversion-related thio-phene and pyrazole rings [inter-centroid distance = 3.7516 (14) Å; inter-planar distance = 3.5987 (10) Å; slippage = 1.06 Å].

  10. ETHIOPIAN RIFT AND ADJACENT HIGHLANDS

    African Journals Online (AJOL)

    of the kinetic temperature of the central Ethiopian rift lakes and adjacent highlands. ... component of the surface radiation balance from only one surface measurement derived from NOAA. TM and ... The basin studied is part of the Ethiopian Rift system bounded within the limits .... Topographic conditions, which determine ...

  11. Methyl 2-(8a-hy-droxy-4a-methyl-8-methyl-enedeca-hydro-naphthalen-2-yl)acrylate.

    Science.gov (United States)

    Tebbaa, Mohamed; Benharref, Ahmed; Oudahmane, Abdelghani; Mellouki, Fouad; Berraho, Moha

    2012-01-01

    The title compound, C(16)H(24)O(3), was synthesized from ilicic acid which was isolated from the aerial part of Inula Viscosa- (L) Aiton [or Dittrichia Viscosa- (L) Greuter]. The mol-ecule contains two fused six-membered rings both in chair conformations. In the crystal, mol-ecules are linked into chains running parallel to the a axis by O-H⋯O hydrogen bonds.

  12. Methyl 2-(4a,8-Dimethyl-7-oxodeca-hydro-naphthalen-2-yl)acrylate.

    Science.gov (United States)

    Tebbaa, Mohamed; Benharref, Ahmed; Daran, Jean-Claude; Barkaoui, Latifa; Berraho, Moha

    2012-08-01

    The title compound, C(16)H(24)O(3), was isolated from the aerial part of Inula Viscosa- (L) Aiton [or Dittrichia Viscosa- (L) Greuter]. The mol-ecule contains two fused (trans) six-membered rings which both exibit a chair conformation. In the crystal, mol-ecules are linked into chains along [100] by weak C-H⋯O hydrogen bonds involving the methyl and carbonyl groups.

  13. 1-[(2R,4aR,8R,8aR)-8-Hy-droxy-4a,8-di-methyl-perhydronaphthalen-2-yl]ethan-1-one.

    Science.gov (United States)

    Tebbaa, Mohamed; Benharref, Ahmed; Berraho, Moha; Daran, Jean-Claude; Akssira, Mohamed; Elhakmaoui, Ahmed

    2011-02-12

    The title compound, C(14)H(24)O(2), was synthesized from ilicic acid, which was isolated from the aerial part of Inula Viscosa- (L) Aiton [or Dittrichia Viscosa- (L) Greuter]. The mol-ecule contains two fused six-membered rings, which both display a chair conformation. In the crystal, mol-ecules are linked into chains propagating along the b axis by inter-molecular O-H⋯O hydrogen bonds.

  14. (2,6-Diisopropyl-phen-yl)(2-thienylmethyl-ene)amine.

    Science.gov (United States)

    Imhof, Wolfgang

    2009-02-25

    The title compound, C(17)H(21)NS, was prepared by the condensation of thio-phene-2-carbaldehyde with 2,6-diiso-propyl-aniline. It crystallizes with two mol-ecules in the asymmetric unit. The mol-ecules are inter-connected via a C-H⋯N hydrogen bond. The dihedral angles between the thio-phene and phenyl rings are 81.7 (7) and 85.5 (7)°.

  15. (2E)-1-(5-Chloro-thio-phen-2-yl)-3-(2,4,5-trimeth-oxy-phen-yl)prop-2-en-1-one.

    Science.gov (United States)

    Prabhu, A N; Jayarama, A; Row, T N Guru; Upadhyaya, V

    2011-08-01

    In the title mol-ecule, C(16)H(15)ClO(4)S, the chloro-thio-phene and trimeth-oxy-phenyl rings make a dihedral angle of 31.12 (5)°. The C=C double bond exhibits an E conformation. In the crystal, C-H⋯O inter-actions generate bifurcated bonds, linking the mol-ecules into chains along the b axis.

  16. (E)-1-Benzyl-idene-2,2-diphenyl-hydrazine.

    Science.gov (United States)

    Mendoza, Angel; Meléndrez-Luevano, Ruth; Cabrera-Vivas, Blanca M; Lozano-Márquez, Claudia D; Carranza, Vladimir

    2012-02-01

    The asymmetric unit of the title compound, C(19)H(16)N(2), contains two independent mol-ecules, both of which show an E configuration with respect to the C=N bond. The dihedral angles between the phenyl rings bonded to the hydrazine group are 81.00 (10) and 88.34 (8)° in the two mol-ecules. Inter-molecular C-H⋯π inter-actions are observed in the crystal structure.

  17. N-(3-Chloro-phen-yl)-4-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-12-01

    There are two independent mol-ecules in the asymmetric unit of the title compound, C12H9ClN2O4S, in which the dihedral angles between the planes of the benzene rings are 46.90 (14) and 44.50 (14)°. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into zigzag chains parallel to the a axis.

  18. N-(3,5-Dimethyl-phen-yl)-4-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-12-01

    There are two independent mol-ecules in the asymmetric unit of the title compound, C14H14N2O4S, in which the dihedral angles between the benzene rings are 56.22 (15) and 58.16 (14)°. In the crystal, N-H⋯Onitro hydrogen bonds link the mol-ecules into zigzag chains running along the a-axis direction.

  19. N-(3-Methyl-benzo-yl)benzene-sulfonamide.

    Science.gov (United States)

    Suchetan, P A; Foro, Sabine; Gowda, B Thimme

    2012-05-01

    The asymmetric unit of the title compound, C(14)H(13)NO(3)S, contains three independent mol-ecules in which the dihedral angles between the sulfonyl and benzoyl benzene rings are 83.3 (2), 84.4 (2) and 87.6 (2)°. In the crystal, mol-ecules are linked into chains running along the a axis via N-H⋯O hydrogen bonds.

  20. Crystal structure of cyclo-bis-(μ4-2,2-di-allyl-malonato-κ(6) O (1),O (3):O (3):O (1'),O (3'):O (1'))tetra-kis-(triphenyl-phosphane-κP)tetra-silver(I).

    Science.gov (United States)

    Frenzel, Peter; Jakob, Alexander; Schaarschmidt, Dieter; Rüffer, Tobias; Lang, Heinrich

    2014-10-01

    In the tetra-nuclear mol-ecule of the title compound, [Ag4(C9H10O4)2(C18H15P)4], the Ag(I) ion is coordinated by one P and three O atoms in a considerably distorted tetra-hedral environment. The two 2,2-di-allyl-malonate anions bridge four Ag(I) ions in a μ4-(κ(6) O (1),O (3):O (3):O (1'),O (3'):O (1')) mode, setting up an Ag4O8P4 core (point group symmetry -4..) of corner-sharing tetra-hedra. The shortest intra-molecular Ag⋯Ag distance of 3.9510 (3) Å reveals that no direct d (10)⋯d (10) inter-actions are present. Four weak intra-molecular C-H⋯O hydrogen bonds are observed in the crystal structure of the title compound, which most likely stabilize the tetra-nuclear silver core.

  1. Crystal structure of 3-{[4-(2-meth-oxy-phen-yl)piperazin-1-yl]meth-yl}-5-(thio-phen-2-yl)-1,3,4-oxa-diazole-2(3H)-thione.

    Science.gov (United States)

    Al-Alshaikh, Monirah A; Abuelizz, Hatem A; El-Emam, Ali A; Abdelbaky, Mohammed S M; Garcia-Granda, Santiago

    2016-02-01

    The title compound, C18H20N4O2S2, is a new 1,3,4-oxa-diazole and a key pharmacophore of several biologically active agents. It is composed of a meth-yl(thio-phen-2-yl)-1,3,4-oxa-diazole-2(3H)-thione moiety linked to a 2-meth-oxy-phenyl unit via a piperazine ring that has a chair conformation. The thio-phene ring mean plane lies almost in the plane of the oxa-diazole ring, with a dihedral angle of 4.35 (9)°. The 2-meth-oxy-phenyl ring is almost normal to the oxa-diazole ring, with a dihedral angle of 84.17 (10)°. In the crystal, mol-ecules are linked by weak C-H⋯S hydrogen bonds and C-H⋯π inter-actions, forming layers parallel to the bc plane. The layers are linked via weak C-H⋯O hydrogen bonds and slipped parallel π-π inter-actions [inter-centroid distance = 3.6729 (10) Å], forming a three-dimensional structure. The thio-phene ring has an approximate 180° rotational disorder about the bridging C-C bond.

  2. Crystal structure of di-chlorido-{4-[(E)-(meth-oxy-imino-κN)meth-yl]-1,3-thia-zol-2-amine-κN (3)}palladium(II).

    Science.gov (United States)

    Dyakonenko, Viktorita V; Zholob, Olga O; Orysyk, Svitlana I; Pekhnyo, Vasily I

    2015-01-01

    In the title compound, [PdCl2(C5H7N3OS)], the Pd(II) atom adopts a distorted square-planar coordination sphere defined by two N atoms of the bidentate ligand and two Cl atoms. The mean deviation from the coordination plane is 0.029 Å. The methyl group is not coplanar with the plane of the metallacycle [torsion angle C-O-N-C = 20.2 (4)°]. Steric repulsion between the methyl group and atoms of the metallacycle is manifested by shortened intra-molecular H⋯C contacts of 2.27, 2.38 and 2.64 Å, as compared with the sum of the van der Waals radii of 2.87 Å. The amino group participates via one H atom in the formation of an intra-molecular N-H⋯Cl hydrogen bond. In the crystal, the other H atom of the amino group links mol-ecules via bifurcated N-H⋯(Cl,O) hydrogen bonds into chains parallel to [001].

  3. Crystal structure of bis-[μ-(4-meth-oxy-phen-yl)methane-thiol-ato-κ(2) S:S]bis-[chlorido-(η(6)-1-isopropyl-4-methyl-benzene)-ruthenium(II)] chloro-form disolvate.

    Science.gov (United States)

    Stíbal, David; Süss-Fink, Georg; Therrien, Bruno

    2015-10-01

    The mol-ecular structure of the title complex, [Ru2(C8H9OS)2Cl2(C10H14)2]·2CHCl3 or (p-MeC6H4Pr (i) )2Ru2(SCH2-p-C6H5-OCH3)2Cl2·2CHCl3, shows inversion symmetry. The two symmetry-related Ru(II) atoms are bridged by two 4-meth-oxy-α-toluene-thiol-ato [(4-meth-oxy-phen-yl)methane-thiol-ato] units. One chlorido ligand and the p-cymene ligand complete the typical piano-stool coordination environment of the Ru(II) atom. In the crystal, the CH moiety of the chloro-form mol-ecule inter-acts with the chlorido ligand of the dinuclear complex, while one Cl atom of the solvent inter-acts more weakly with the methyl group of the bridging 4-meth-oxy-α-toluene-thiol-ato unit. This assembly leads to the formation of supra-molecular chains extending parallel to [021].

  4. Crystal structure of catena-poly[bis(formato-κO)bis-[μ2-1,1'-(1,4-phenyl-ene)bis-(1H-imidazole)-κ(2) N (3):N (3')]cobalt(II)].

    Science.gov (United States)

    Xu, Guo-Wang; Wang, Ye-Nan; Xia, Hong-Xu; Wang, Zhong-Long

    2015-09-01

    A red block-shaped crystal of the title compound, [Co(HCOO)2(C12H10N4)2] n , was obtained by the reaction of cobalt(II) nitrate hexa-hydrate, formic acid and 1,1'-(1,4-phenyl-ene)bis-(1H-imidazole) (bib) mol-ecules. The asymmetric unit consists of one Co(II) cation, one formate ligand and two halves of a bib ligand. The central Co(II) cation, located on an inversion centre, is coordinated by two carboxyl-ate O atoms and four N atoms from bib ligands, completing an octa-hedral coordination geometry. The Co(II) centres are bridged by bib ligands, giving a two-dimensional net. Topologically, taking the Co(II) atoms as nodes and the bib ligands as linkers, the two-dimensional structure can be simplified as a typical sql/Shubnikov tetra-gonal plane network. The structure features C-H⋯O hydrogen-bonding inter-actions between formate and bib ligands, resulting in a three-dimensional supra-molecular network.

  5. Crystal structure of bis-[2-tert-but-oxy-6-fluoro-3-(pyridin-2-yl-κN)pyridin-4-yl-κC (4)](pentane-2,4-dionato-κ(2) O,O')iridium(III).

    Science.gov (United States)

    Park, Ki-Min; Kang, Youngjin

    2014-11-01

    The title mol-ecule, [Ir(C14H14FN2O)2(C5H7O2)], is located on a twofold rotation axis, which passes through the Ir(III) atom and the central C atom of the pentane-2,4-dionate anion. The Ir(III) atom adopts a distorted octa-hedral coordination geometry, being C,N-chelated by two 2-tert-but-oxy-6-fluoro-3-(pyridin-2-yl)pyridin-4-yl ligands and O,O'-chelated by the pentane-2,4-dionato ligand. The bipyridinate ligands, which are perpendicular to each other [dihedral angle between the two least-squares planes = 89.95 (5)°], are arranged in a cis-C,C' and trans-N,N' fashion relative to the central metal cation. Intra-molecular C-H⋯O and C-H⋯N hydrogen bonds and inter-molecular C-H⋯F hydrogen bonds as well as π-π inter-actions between neighbouring pyridine rings [centroid-centroid distance 3.680 (1) Å] contribute to the stabilization of the mol-ecular and crystal structure, respectively.

  6. Crystal structure of ethyl (2S,2'R)-1'-benzyl-3-oxo-3H-di-spiro-[1-benzo-thio-phene-2,3'-pyrrolidine-2',11''-indeno[1,2-b]quinoxaline]-4'-carboxyl-ate.

    Science.gov (United States)

    Govindaraj, J; Raja, R; Suresh, M; Raghunathan, R; SubbiahPandi, A

    2015-03-01

    In the title compound, C35H27N3O3S, the spiro-linked five-membered rings both adopt twisted conformations. The pyrrolidine ring makes dihedral angles of 80.5 (1) and 77.4 (9)° with the benzo-thio-phene ring system and the quinoxaline ring system, respectively. The S atom and C=O unit of the benzo-thio-phene ring system are disordered over two opposite orientations in a 0.768 (4):0.232 (4) ratio. The atoms of the ethyl side chain are disordered over two sets of sites in a 0.680 (16):0.320 (16) ratio. In the crystal, mol-ecules are linked by C-H⋯O, C-H⋯N and π-π inter-actions [shortest centroid-centroid distance = 3.4145 (19) Å], resulting in a three-dimensional network.

  7. Synthesis and crystal structure of trans-di-chlorido[3-methyl-1-(4-vinyl-benz-yl)-1H-imidazol-3-ium-2-yl-κC (2)](4-phenyl-pyridine-κN)palladium(II).

    Science.gov (United States)

    Majeed, Maitham H; Wendt, Ola F

    2016-04-01

    The title compound, [PdCl2(C11H9N)(C13H14N2)], represents a new class of palladium-based polymerizable monomer which could give a potentially catalytically active polymer. It was synthesized via transmetallation from the corresponding silver complex. The Pd(II) ion coordinates two Cl anions, one C atom from the N-heterocyclic carbene (NHC) ligand and one N atom from the 4-phenyl-pyridine ligand, displaying a slightly distorted square-planar geometry. The dihedral angle between the imidazole ring and the pyridine ring is 34.53 (8)°. The Pd-C bond length between the NHC ligand and the Pd(II) ion is 1.9532 (16) Å. In the crystal, weak non-classical C-H⋯Cl hydrogen bonds link the mol-ecules into a tape structure along [101]. A weak π-π inter-action is also observed [centroid-centroid distance = 3.9117 (11) Å].

  8. Tetra-kis(5,7-dimethyl-quinolin-8-olato-κ(2)N,O)zirconium(IV) dimethyl-form-amide disolvate.

    Science.gov (United States)

    Steyn, Maryke; Visser, Hendrik G; Roodt, Andreas

    2012-11-01

    In the title compound, [Zr(C(11)H(10)NO)(4)]·2C(3)H(7)NO, the Zr(IV) ion is coordinated by four bidentate 5,7-dimethylquinolin-8-olate ligands in a slightly distorted square-anti-prismatic coordination environment. The asymmetric unit also contains two N,N'-dimethyl-formamide (DMF) solvent mol-ecules. In the crystal, a weak C-H⋯O hydrogen bond links the complex mol-ecule to a solvent mol-ecule and weak π-π stacking inter-actions [centroid-centroid distance = 3.671 (3) Å] also occur. One of the DMF solvent mol-ecules was refined as disordered over three sets of sites, with refined occupancies in the ratio of 0.391 (9):0.342 (10):0.267 (7).

  9. Crystal structures of three 6-substituted coumarin-3-carboxamide derivatives.

    Science.gov (United States)

    Gomes, Lígia R; Low, John Nicolson; Fonseca, André; Matos, Maria João; Borges, Fernanda

    2016-07-01

    Three coumarin derivatives, viz. 6-methyl-N-(3-methyl-phen-yl)-2-oxo-2H-chromene-3-carboxamide, C18H15NO3 (1), N-(3-meth-oxy-phen-yl)-6-methyl-2-oxo-2H-chromene-3-carboxamide, C18H15NO4 (2), and 6-meth-oxy-N-(3-meth-oxy-phen-yl)-2-oxo-2H-chromene-3-carboxamide, C18H15NO5 (3), were synthesized and structurally characterized. The mol-ecules display intra-molecular N-H⋯O and weak C-H⋯O hydrogen bonds, which probably contribute to the approximate planarity of the mol-ecules. The supra-molecular structures feature C-H⋯O hydrogen bonds and π-π inter-actions, as confirmed by Hirshfeld surface analyses.

  10. Adjacency-preserving spatial treemaps

    Directory of Open Access Journals (Sweden)

    Kevin Buchin

    2016-03-01

    Full Text Available Rectangular layouts, subdivisions of an outer rectangle into smaller rectangles, have many applications in visualizing spatial information, for instance in rectangular cartograms in which the rectangles represent geographic or political regions. A spatial treemap is a rectangular layout with a hierarchical structure: the outer rectangle is subdivided into rectangles that are in turn subdivided into smaller rectangles. We describe algorithms for transforming a rectangular layout that does not have this hierarchical structure, together with a clustering of the rectangles of the layout, into a spatial treemap that respects the clustering and also respects to the extent possible the adjacencies of the input layout.

  11. N-Ethyl-2-[1-(2-hy-droxy-4-methyl-phen-yl)ethyl-idene]hydrazinecarbo-thio-amide.

    Science.gov (United States)

    Anderson, Brian J; Hall, Jeffrey R; Jasinski, Jerry P

    2014-06-01

    The title compound, C12H17N3OS, crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. The dihedral angle between the mean planes of the benzene ring and the hydrazinecarbo-thio-amide group are 6.9 (4) and 37.2 (5)° in mol-ecules A and B, respectively. An intra-molecular O-H⋯N hydrogen bond is observed in each mol-ecule. This serves to maintain an approximately planar conformation for mol-ecule A, but leaves a significant twist between these two groups in mol-ecule B. In the crystal, a weak N-H⋯S inter-action is observed, forming inversion dimers among the B mol-ecules and resulting in an R 2 (2)(8) motif. These dimers are further inter-connected by weak N-H⋯O and C-H⋯O inter-molecular inter-actions, forming chains along [011].

  12. Crystal structures of bis-(phen-oxy)silicon phthalocyanines: increasing π-π inter-actions, solubility and disorder and no halogen bonding observed.

    Science.gov (United States)

    Lessard, Benoît H; Lough, Alan J; Bender, Timothy P

    2016-07-01

    We report the syntheses and characterization of three solution-processable phen-oxy silicon phthalocyanines (SiPcs), namely bis-(3-methyl-phen-oxy)(phthalocyanine)silicon [(3MP)2-SiPc], C46H30N8O2Si, bis-(2-sec-butyl-phen-oxy)(phthalocyanine)silicon [(2secBP)2-SiPc], C44H24I2N8O2Si, and bis-(3-iodo-phen-oxy)(phthalocyanine)silicon [(3IP)2-SiPc], C52H42N8O2Si. Crystals grown of these compounds were characterized by single-crystal X-ray diffraction and the π-π inter-actions between the aromatic SiPc cores were studied. It was determined that (3MP)2-SiPc has similar inter-actions to previously reported bis-(3,4,5-tri-fluoro-phen-oxy)silicon phthalocyanines [(345 F)2-SiPc] with significant π-π inter-actions between the SiPc groups. (3IP)2-SiPc and (2secBP)2-SiPc both experienced a parallel stacking of two of the peripheral aromatic groups. In all three cases, the solubility of these mol-ecules was increased by the addition of phen-oxy groups while maintaining π-π inter-actions between the aromatic SiPc groups. The solubility of (2secBP)2-SiPc was significantly higher than other bis-phen-oxy-SiPcs and this was exemplified by the higher observed disorder within the crystal structure.

  13. Crystal structure of hexa-aqua-nickel(II) bis{2-[(5,6-di-hy-droxy-3-sul-fon-ato-quino-lin-1-ium-7-yl)oxy]acetate} dihydrate.

    Science.gov (United States)

    Le Thi Hong, Hai; Nguyen Thi Ngoc, Vinh; Tran Thi, Da; Nguyen Bich, Ngan; Van Meervelt, Luc

    2015-09-01

    The asymmetric unit of the title compound, [Ni(H2O)6](C11H8NO8S)2·2H2O, features a half-hexa-aqua-nickel(II) complex cation with the Ni(II) ion on an inversion center, one deprotonated 5,6-dihy-droxy-3-sulfoquinolin-7-yloxyacetic acid (QOH) molecule appearing in its zwitterionic form and one lattice water mol-ecule. The sulfonate group is disordered over two positions with occupancy factors of 0.655 (5) and 0.345 (5). The hexa-aqua-nickel(II) cation inter-acts through hydrogen bonding with eight QOH mol-ecules and two water mol-ecules. The six-membered rings of quinoline show π-π stacking [centroid-to-centroid distances of 3.679 (2) Å and 3.714 (2) Å].

  14. Bis{μ-2-[(pyrimidin-2-yl)amino-meth-yl]phenolato}-κ(2) N (1):O;κ(2) O:N (1)-bis-({2-[(pyrimidin-2-yl-κN)amino-meth-yl]phenol}silver(I)) dihydrate.

    Science.gov (United States)

    Gao, Shan; Ng, Seik Weng

    2012-12-01

    The Ag(I) atom in the title centrosymmetric dinuclear compound, [Ag2(C11H10N3O)2(C11H11N3O)2]·2H2O, shows a T-shaped coordination arising from bonding to the N atom of a neutral 2-[(pyrimidin-2-yl)amino-meth-yl]phenol ligand, the N atom of the 2-[(pyrimidin-2-yl)amino-meth-yl]phenolate anion [N-Ag-N = 171.8 (1)°] and the terminal O atom of the other anion [Ag-O = 2.606 (3) Å]. A pair of 2-[(pyrimidin-2-yl)amino-meth-yl]phenolate anions link the two Ag(I) atoms to form the dinuclear compound. In the crystal, adjacent dinuclear mol-ecules are linked to the lattice water mol-ecules, generating an O-H⋯O- and N-H⋯O-connected three-dimensional network. In the crystal, the hy-droxy H atom is disordered over two positions in a 1:1 ratio; one half-occupancy H atom is connected to one hy-droxy group, whereas the other half-occupancy H atom is connected to another hy-droxy group.

  15. 1-{[4'-(1H-1,2,4-Triazol-2-ium-1-ylmeth-yl)biphenyl-4-yl]meth-yl}-1H-1,2,4-triazol-2-ium bis-(3-carb-oxy-5-iodo-benzoate)-5-iodo-benzene-3,5-dicarb-oxy-lic acid-water (1/2/2).

    Science.gov (United States)

    Zhang, Kou-Lin; Deng, Ye; Ng, Seik Weng

    2012-05-01

    The neutral carb-oxy-lic acid mol-ecule and the carboxyl-ate anion in the title compound, C(18)H(18)N(6) (2+)·2C(8)H(4)IO(4) (-)·2C(8)H(5)IO(4)·2H(2)O, are both nearly planar (r.m.s. deviations = 0.034 and 0.045 Å, respectively). In the cation, the mid-point of the C-C bond linking the two benzene rings lies on a center of inversion, and the triazole ring is approximately perpendicular to the adjacent benzene ring [dihedral angle = 83.2 (3)°]. In the crystal, the cations, anions, carb-oxy-lic acid and lattice water mol-ecules are linked by N-H⋯O, O-H⋯N and O-H⋯O hydrogen bonds, generating a ribbon running along [1-10]. The crystal studied was a non-merohedral twin with the components in a 51.2 (1):48.8 (1) ratio.

  16. 3-Acetyl-1-(2,3-dimethyl-phen-yl)thio-urea.

    Science.gov (United States)

    Kumar, Sharatha; Foro, Sabine; Gowda, B Thimme

    2012-07-01

    In the crystal structure of the title compound, C(11)H(14)N(2)OS, the conformation of the two N-H bonds is anti. The conformation of the C=S and the C=O bonds is also anti. Furthermore, the N-H bond adjacent to the benzene ring is anti to the ortho- and meta-methyl groups. The dihedral angle between the benzene ring and the side chain [N-C(= S)-N-C(=O)-C; maximum deviation = 0.047 (4) Å] is 81.33 (10)°. The NH hydrogen adjacent to the benzene ring and the amide O atom exhibit bifurcated intra- and inter-molecular hydrogen bonding. In the crystal, mol-ecules form inversion dimers, which are linked into chains via R(2) (2)(12) and R(2) (2)(8) networks.

  17. Distinguishing tautomerism in the crystal structure of (Z)-N-(5-ethyl-2,3-di-hydro-1,3,4-thiadiazol-2-ylidene) -4-methylbenzenesulfonamide using DFT-D calculations and {sup 13}C solid-state NMR

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaozhou; Bond, Andrew D.; Johansson, Kristoffer E.; Van de Streek, Jacco, E-mail: jacco.vandestreek@sund.ku.dk [Department of Pharmacy, University of Copenhagen, Universitetsparken 2, Copenhagen DK-2100 (Denmark)

    2014-08-01

    The crystal structure of (Z)-N-(5-ethyl-2,3-di-hydro-1,3,4-thiadiazol-2-ylidene) -4-methylbenzenesulfonamide contains an imine tautomer, rather than the previously reported amine tautomer. The tautomers can be distinguished using dispersion-corrected density functional theory calculations and by comparison of calculated and measured {sup 13}C solid-state NMR spectra. The crystal structure of the title compound, C{sub 11}H{sub 13}N{sub 3}O{sub 2}S{sub 2}, has been determined previously on the basis of refinement against laboratory powder X-ray diffraction (PXRD) data, supported by comparison of measured and calculated {sup 13}C solid-state NMR spectra [Hangan et al. (2010 ▶). Acta Cryst. B66, 615–621]. The mol@@ecule is tautomeric, and was reported as an amine tautomer [systematic name: N-(5-ethyl-1,3,4-thia@@diazol-2-yl)-p-toluene@@sulfonamide], rather than the correct imine tautomer. The protonation site on the mol@@ecule’s 1,3,4-thia@@diazole ring is indicated by the inter@@molecular contacts in the crystal structure: N—H⋯O hydrogen bonds are established at the correct site, while the alternative protonation site does not establish any notable inter molecular inter@@actions. The two tautomers provide essentially identical Rietveld fits to laboratory PXRD data, and therefore they cannot be directly distinguished in this way. However, the correct tautomer can be distinguished from the incorrect one by previously reported qu@@anti@@tative criteria based on the extent of structural distortion on optimization of the crystal structure using dispersion-corrected density functional theory (DFT-D) calculations. Calculation of the {sup 13}C SS-NMR spectrum based on the correct imine tautomer also provides considerably better agreement with the measured {sup 13}C SS-NMR spectrum.

  18. Crystal structure of (1S,3R,8R,9R,10S)-2,4,6-tris-(2,2-di-chloro-3,7,7,10-tetra-methyl-tri-cyclo-[6.4.0.0(1,3)]dodec-9-yl)cyclo-triboroxane.

    Science.gov (United States)

    Benharref, Ahmed; El Ammari, Lahcen; Saadi, Mohamed; Mazoir, Noureddine; Berraho, Moha

    2015-08-01

    The title compound, C48H75B3Cl6O3, was synthesized in two steps from β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzo-cyclo-hept-ene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The mol-ecule consists of an almost planar cyclo-triboroxane ring [maximum deviation = 0.036 (2) Å] linked to three identical fused ring systems with different conformations. Each of the three attached ring systems is built up from a seven-membered ring to which a six- and a three-membered ring are fused. The three six-membered rings have a twist-boat conformation, whereas the seven-membered rings display boat, chair and twist-boat conformations. The dihedral angles between the central boroxane ring and the mean planes of the attached six-membered rings are 63.67 (18), 54.89 (2) and 56.57 (19)°. The crystal packing is governed only by van der Waals inter-actions.

  19. Crystallization process

    Science.gov (United States)

    Adler, Robert J.; Brown, William R.; Auyang, Lun; Liu, Yin-Chang; Cook, W. Jeffrey

    1986-01-01

    An improved crystallization process is disclosed for separating a crystallizable material and an excluded material which is at least partially excluded from the solid phase of the crystallizable material obtained upon freezing a liquid phase of the materials. The solid phase is more dense than the liquid phase, and it is separated therefrom by relative movement with the formation of a packed bed of solid phase. The packed bed is continuously formed adjacent its lower end and passed from the liquid phase into a countercurrent flow of backwash liquid. The packed bed extends through the level of the backwash liquid to provide a drained bed of solid phase adjacent its upper end which is melted by a condensing vapor.

  20. Compressed Adjacency Matrices: Untangling Gene Regulatory Networks.

    Science.gov (United States)

    Dinkla, K; Westenberg, M A; van Wijk, J J

    2012-12-01

    We present a novel technique-Compressed Adjacency Matrices-for visualizing gene regulatory networks. These directed networks have strong structural characteristics: out-degrees with a scale-free distribution, in-degrees bound by a low maximum, and few and small cycles. Standard visualization techniques, such as node-link diagrams and adjacency matrices, are impeded by these network characteristics. The scale-free distribution of out-degrees causes a high number of intersecting edges in node-link diagrams. Adjacency matrices become space-inefficient due to the low in-degrees and the resulting sparse network. Compressed adjacency matrices, however, exploit these structural characteristics. By cutting open and rearranging an adjacency matrix, we achieve a compact and neatly-arranged visualization. Compressed adjacency matrices allow for easy detection of subnetworks with a specific structure, so-called motifs, which provide important knowledge about gene regulatory networks to domain experts. We summarize motifs commonly referred to in the literature, and relate them to network analysis tasks common to the visualization domain. We show that a user can easily find the important motifs in compressed adjacency matrices, and that this is hard in standard adjacency matrix and node-link diagrams. We also demonstrate that interaction techniques for standard adjacency matrices can be used for our compressed variant. These techniques include rearrangement clustering, highlighting, and filtering.

  1. Crystal structure of a binuclear nickel(II) complex constructed of 1H-imidazo[4,5-f][1,10]phenanthroline and doubly deprotonated benzene-1,3,5-tri-carb-oxy-lic acid.

    Science.gov (United States)

    Lv, Ying; Hao, Xiang-Rong

    2015-04-01

    The title complex, [Ni2(C9H4O6)2(C13H8N4)2(H2O)4]·2H2O, bis-(μ-5-carb-oxy-benzene-1,3-di-carboxyl-ato-κ(2) O (1):O (1'))bis-[di-aqua(1H-imidazo[4,5-f][1,10]phenanthroline-κ(2) N (7),N (8))nickel(II)] di-hydrate, was obtained under solvothermal conditions by the reaction of benzene-1,3,5-tricarboxylic acid (H3BTC) with Ni(NO3)2 in the presence of 1H-imidazo[4,5-f][1,10]phenanthroline (IP). The crystal has triclinic (P-1) symmetry with a centrosymmetric binuclear nickel(II) cluster. The Ni(II) atom is coordinated by two N atoms from a chelating 1H-imidazo[4,5-f][1,10]phenanthroline ligand, two carboxyl-ate O atoms from two 5-carb-oxy-benzene-1,3-di-carboxyl-ate ligands and two water mol-ecules in a slightly distorted octa-hedral geometry. Two carboxyl-ate groups bridge two Ni(II) cations, forming the binuclear complex. Extensive N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonding is present in the crystal structure, forming a three-dimensional supermolecular framework. Weak π-π stacking is observed between parallel HBTC(2-) and IP ring systems, the face-to-face separation being 3.695 (2) Å.

  2. N-(3,5-Dimethyl-phen-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-10-01

    The asymmetric unit of the title compound, C(14)H(14)N(2)O(4)S, consists of two crystallographically independent mol-ecules. The mol-ecules are twisted at the S-N bonds with C-S-N-C torsion angles of 44.2 (3) and -49.3 (3)°. The dihedral angles between the benzene rings in the two mol-ecules are 71.53 (7) and 72.11 (7)°. The amide H atoms exhibit bifurcated intra- and inter-molecular hydrogen bonds; the intra-molecular N-H⋯O(N) hydrogen bonds generate S(7) motifs. In the crystal, the independent mol-ecules are separately connected through the inter-molecular N-H⋯O(S) hydrogen bonds, generating a C(4) motif and a helical chain along the b axis for one mol-ecule and an R(2) (2)(8) motif and an inversion dimer for the other. The crystal studied was a pseudo-merohedral twin with twin law (-100/0-10/001), the refined ratio of the twin domains being 0.7876 (12):0.2124 (12).

  3. Crystal structure of tris-(1,3-dimesityl-4,5-di-hydro-1H-imidazol-3-ium) tetra-bromido-cobaltate(II) bromide chloro-form hexa-solvate.

    Science.gov (United States)

    Rais, Eduard; Flörke, Ulrich; Wilhelm, René

    2015-10-01

    In the unit cell of the title compound, (C21H27N2)3[CoBr4]Br·6CHCl3, the tetrabromidocobaltate(II) anion and the bromide anion are located on a crystallographic threefold rotation axis. For the [CoBr4](2-) group, the axis runs through one of the Br ligands and the Co(II) atom. All other structure moieties lie on general sites. Various tris-(1,3-dimesityl-4,5-di-hydro-1H-imidazol-3-ium) structures with different counter-ions have been reported. In the title compound, the N-C-N angle is 113.7 (5)°, with short C-N bond lengths of 1.297 (7) and 1.307 (7) Å. The two mesityl planes make a dihedral angle of 34.6 (1)° and the dihedral angles between the mesityl and N-C-N planes are 82.0 (1) and 88.5 (1)°, respectively. The imidazoline ring is almost planar, with atom deviations in the range 0.003 (5)-0.017 (5) Å from the best plane; the mean deviation is 0.012 (5) Å. In the crystal, non-covalent inter-actions of the C-H⋯Br type occur between the Br(-) anion and the cation, as well as between the [CoBr4](2-) anion and both the chloro-form solvent mol-ecules. These H⋯A distances are slightly shorter than the sum of van der Waals radii.

  4. Determinants of adjacency matrices of graphs

    Directory of Open Access Journals (Sweden)

    Alireza Abdollahi

    2012-12-01

    Full Text Available We study the set of all determinants of adjacency matrices of graphs with a given number of vertices. Using Brendan McKay's data base of small graphs, determinants of graphs with at most $9$ vertices are computed so that the number of non-isomorphic graphs with given vertices whose determinants are all equal to a number is exhibited in a table. Using an idea of M. Newman, it is proved that if $G$ is a graph with $n$ vertices and ${d_1,dots,d_n}$ is the set of vertex degrees of $G$, then $gcd(2m,d^2$ divides the determinant of the adjacency matrix of $G$, where $d=gcd(d_1,dots,d_n$. Possible determinants of adjacency matrices of graphs with exactly two cycles are obtained.

  5. Poly[[aquadi-μ(3)-malonato-hexaphenyl-ditin(IV)] acetone solvate].

    Science.gov (United States)

    Win, Yip Foo; Teoh, Siang Guan; Vikneswaran, M R; Goh, Jia Hao; Fun, Hoong-Kun

    2010-05-22

    The asymmetric unit of the title polymeric complex, {[Sn(2)=(C(6)H(5))(6)(C(3)H(2)O(4))(H(2)O)]·C(3)H(6)O}(n), comprises of two Sn cations, one malonate anion and a non-coordinating acetone solvent mol-ecule. Both crystallographically independent Sn cations are five-coordinated by two O and three C atoms in a distorted trigonal-bipyrimidal geometry. One of the Sn cations is bridged by the malonate units, affording polymeric chains which run along [001]. Weak intra-molecular C-H⋯π inter-actions stabilize the mol-ecular structure. In the crystal structure, adjacent chains are inter-connected by inter-molecular O-H⋯O and C-H⋯O hydrogen bonds into a three-dimensional supra-molecular structure. A weak inter-molecular C-H⋯π inter-action is also observed.

  6. Bis{μ-2-meth-oxy-6-[(methyl-imino)-meth-yl]phenolato}bis-({2-meth-oxy-6-[(methyl-imino)-meth-yl]phenolato}copper(II)).

    Science.gov (United States)

    Sydoruk, Tetyana V; Buvaylo, Elena A; Kokozay, Vladimir N; Vassilyeva, Olga Yu; Skelton, Brian W

    2013-01-01

    The title compound, [Cu2(C9H10NO2)4], is built of discrete centrosymmetric dimers. The Cu(II) atoms are each five coordinated by two deprotonated Schiff base ligands that are bonded differently to the metal atoms. Of the two phenolate O atoms, one is coordinated to one Cu(II) atom, whereas another bridges the two metal atoms. The basal plane of the square pyramid around Cu(II) atoms is formed by the imino N and phenolate O atoms of the bidentate and the monodentate/bidentate Schiff base ligands. The bridging phenolate oxygen occupies the apical position of the coordination sphere with a considerably longer Cu-O bond length. In the crystal, the dimeric mol-ecules pack relative to each other in such a way that the Cu2O2 planes of adjacent dimers are orthogonal.

  7. 1,1'-[(1E,11E)-5,8-Dioxa-2,11-diazo-nia-dodeca-1,11-diene-1,12-di-yl]dinaph-thal-en-2-olate.

    Science.gov (United States)

    Liu, Yanju; Liu, Kai; Cao, Zhiqiang; Niu, Meiju

    2011-05-01

    The title compound, C(28)H(28)N(2)O(4), crystallizes in a zwitterionic form with deprotonated naphthol hy-droxy groups and protonated imine N atoms. The asymmetric unit contains one half-mol-ecule located on a twofold rotation axis. Intra-molecular N-H⋯O hydrogen bonds occur and the two bicyclic ring systems form a dihedral angle of 64.2 (1)°. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into layers parallel to the bc plane.

  8. 4-Amino-pyridinium 5-carb-oxy-penta-noate monohydrate.

    Science.gov (United States)

    Raj, S Alfred Cecil; Sinthiya, A; Varghese, Babu

    2012-07-01

    In the title hydrated salt, C(5)H(7)N(2) (+)·C(6)H(9)O(4) (-)·H(2)O, the carb-oxy H atom is disordered over two positions with equal occupancy. In the crystal, O atoms of the 5-carb-oxy-penta-noate anion link the 4-amino-pyridinium cations and water mol-ecules into a three-dimensional network via N-H⋯O hydrogen bonds. The crystal structure is further consolidated by O-H⋯O hydrogen bonds involving the anion and the solvent water mol-ecule.

  9. N-(2,5-Dimethyl-phen-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-12-01

    In the crystal structure of the title compound, C14H14N2O4S, the N-H bond is syn to the ortho-nitro group in the sulfonyl benzene ring and anti to the ortho- and syn to the meta-methyl groups in the aniline ring. The mol-ecule is twisted at the S-N bond with a torsion angle of 71.41 (18)°. The dihedral angle between the planes of the benzene rings is 51.07 (8)°. In the crystal, pairs of N-H⋯Osulfonamide hydrogen bonds link the mol-ecules into inversion dimers.

  10. N-(4-Chloro-phenyl-sulfon-yl)-2-methyl-propanamide.

    Science.gov (United States)

    Nirmala, P G; Foro, Sabine; Gowda, B Thimme

    2011-09-01

    In the crystal structure of the title compound, C(10)H(12)ClNO(3)S, the N-C bond in the C-SO(2)-NH-C segment has a gauche torsion with respect to the S=O bonds. The mol-ecule is twisted at the S atom with a C-S-N-C torsion angle of -62.3 (3)°. The benzene ring and the SO(2)-NH-CO-C segment form a dihedral angle of 89.3 (1)°. In the crystal, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds into inversion dimers.

  11. N-(4-Methyl-phen-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-09-01

    In the crystal of the title compound, C(13)H(12)N(2)O(4)S, the conformation of the N-H bond in the -SO(2)-NH- segment is syn to the ortho-nitro group in the sulfonyl benzene ring. The mol-ecule is twisted at the S-N bond with a torsion angle of 76.55 (18)°. The dihedral angle between the planes of the rings is 72.64 (8)°. In the crystal, mol-ecules are linked by pairs of N-H⋯O(S) hydrogen bonds to form inversion dimers.

  12. 4-(4-Chloro-phen-yl)-6-hydr-oxy-5-(2-thienyl-carbonyl)-6-(trifluoro-meth-yl)-3,4,5,6-tetra-hydro-pyrimidin-2(1H)-one monohydrate.

    Science.gov (United States)

    Mosslemin, Mohammad Hossein; Nateghi, Mohammad Reza; Sadoughi, Hesamaddin; Lamei, Asal

    2009-05-20

    The asymmetric unit of the title compound, C(16)H(12)ClF(3)N(2)O(3)S·H(2)O, contains two crystallographically independent organic mol-ecules and two water mol-ecules. The organic species are linked by an inter-molecular O-H⋯O hydrogen bond, while the water mol-ecules are connected to them through inter-molecular O-H⋯N hydrogen bonds. The thio-phene and phenyl rings are oriented at dihedral angles of 62.35 (4) in the first independent mol-ecule and 60.74 (5)° in the second, while the pyrimidine rings adopt twisted conformations in both molecules. Intra-molecular N-H⋯F inter-actions result in the formation of two five-membered rings having envelope conformations. In the crystal structure, further inter-molecular O-H⋯O and N-H⋯O hydrogen bonds link the mol-ecules into chains.

  13. Aqua{4,4',6,6'-tetrachloro-2,2'-[(2,2-dimethylpropane-1,3-diyl)bis(nitrilomethanylylidene)]diphenolato}zinc.

    Science.gov (United States)

    Kargar, Hadi; Kia, Reza; Abbasian, Saeideh; Tahir, Muhammad Nawaz

    2012-07-01

    The asymmetric unit of the title compound, [Zn(C(19)H(16)Cl(4)N(2)O(2))(H(2)O)], comprises two crystallographically independent mol-ecules. The geometry around the Zn(II) atoms is distorted trigonal-bipyramidal, supported by the N(2)O(2) donor atoms of the tetradentate Schiff base and a coordinating water mol-ecule. The dihedral angles between the benzene rings in the two mol-ecules are 34.10 (15) Å and 30.61 (15) Å. In the crystal, neighbouring independent mol-ecules are linked by pairs of O-H⋯O hydrogen bonds, forming dimers with R(2) (2)(6) ring motifs, and by O-H⋯Cl hydrogen bonds. There are short Cl⋯Cl [3.4728 (16), 3.4863 (16), and 3.388 (1) Å] contacts present, and mol-ecules are also linked by C-H⋯O and π-π [centroid-centroid distance = 3.671 (2) Å] inter-actions.

  14. 4-(Piperidin-1-yl)-4H-benzo[b]tetra-zolo[1,5-d][1,4]diazepin-5(6H)-one.

    Science.gov (United States)

    Nichol, Gary S; Xu, Zhigang; Kaiser, Christine E; Hulme, Christopher

    2010-12-04

    There are two crystallographically unique mol-ecules present in the asymmetric unit of the title compound, C(14)H(16)N(6)O; in both mol-ecules, the seven-membered diazepinone ring adopts a boat-like conformation and the chair conformation piperidine ring is an axial substituent on the diazepinone ring. In the crystal, each mol-ecule forms hydrogen bonds with its respective symmetry equivalents. Hydrogen bonding between mol-ecule A and symmetry equivalents forms two ring motifs, the first formed by inversion-related N-H⋯O inter-actions and the second formed by C-H⋯O and C-H⋯N inter-actions. The combination of both ring motifs results in the formation of an infinite double tape, which propagates in the a-axis direction. Hydrogen bonding between mol-ecule B and symmetry equivalents forms one ring motif by inversion-related N-H⋯O inter-actions and a second ring motif by C-H⋯O inter-actions, which propagate as a single tape parallel with the c axis.

  15. Bis(tetra-ethyl-ammonium) bis-(hydrogen l-tartrate) l-tartaric acid monohydrate.

    Science.gov (United States)

    Rajalakshmi, M; Indirajith, R; Gopalakrishnan, R; Ramamurthi, K; Stoeckli-Evans, Helen

    2011-06-01

    In the title compound, 2C(8)H(20)N(+)·2C(4)H(5)O(6) (-)·C(4)H(6)O(6)·H(2)O, the presence of the two tetra-ethyl-ammonium cations is balanced by two hydrogen l-tartrate anions. Also present in the asymmetric unit are a mol-ecule of l-tartaric acid and a water mol-ecule. The various components are linked by O-H⋯O hydrogen bonds. In the crystal, two-dimensional networks are formed via O-H⋯O hydrogen bonds and C-H⋯O inter-actions involving the water mol-ecule, the hydrogen l-tartrate anions and the l-tartaric acid mol-ecules. These layers, which stack along [001], are separated by tetra-ethyl-ammonium cations. The latter are also involved in C-H⋯O inter-actions with the anions and the l-tartaric acid and water mol-ecules participating in the two-dimensional network.

  16. Novel GluN2B selective NMDA receptor antagonists: relative configuration of 7-meth-oxy-2-methyl-2,3,4,5-tetra-hydro-1H-3-benzazepin-1-ols.

    Science.gov (United States)

    Tewes, Bastian; Frehland, Bastian; Fröhlich, Roland; Wünsch, Bernhard

    2016-05-01

    The title compounds, C22H29NO2 (3) and C22H29NO2 (4) [systematic names: (1S*,2R*)-7-meth-oxy-2-methyl-3-(4-phenyl-but-yl)-2,3,4,5-tetra-hydro-1H-3-benzazepin-1-ol and (1R*,2R*)-7-meth-oxy-2-methyl-3-(4-phenyl-but-yl)-2,3,4,5-tetra-hydro-1H-3-benzazepin-1-ol, are diastereomers with the relative configuration of the adjacent hydroxyl and methyl groups at the seven-membered azepine ring being trans in (3) and cis in (4). In the crystals the orientation of these groups is -anti-periplanar (3) and +syn-clinal (4). In both cases, the crystals studied proved to be of a racemic mixture, with relative configurations (R*,S*)-3 and (R*,R*)-4. In both compounds, the seven-membered azepine ring has a chair-like conformation, and the 4-phenyl-butyl side chain adopts a extended conformation in (R*,S*)-3, but a twisted conformation in (R*,R*)-4. In the crystal of (S*,R*)-3, mol-ecules are linked via C-H⋯O hydrogen bonds, forming slabs parallel to the ac plane. In the crystal of (R*,R*)-4, mol-ecules are linked via O-H⋯N hydrogen bonds, forming chains propagating along the c-axis direction. The chains are linked by C-H⋯O hydrogen bonds, forming slabs parallel to the ac plane.

  17. Attachment of Thiobacillus thiooxidans to sulfur crystals.

    Science.gov (United States)

    SCHAEFFER, W I; HOLBERT, P E; UMBREIT, W W

    1963-01-01

    Schaeffer, W. I. (Rutgers, The State University, New Brunswick, N.J.), P. E. Holbert, and W. W. Umbreit. Attachment of Thiobacillus thiooxidans to sulfur crystals. J. Bacteriol. 85:137-140. 1963.-Electron micrographs of replicas of sulfur crystals before and after attack by Thiobacillus thiooxidans show that the microorganisms erode the crystal in the area immediately adjacent to the cell. When there are many cells, the entire crystal surface appears eroded.

  18. Enteroenteroanastomosis near adjacent ileocecal valve in infants

    Institute of Scientific and Technical Information of China (English)

    Wei-Wei Jiang; Xiao-Qun Xu; Qi-Ming Geng; Jie Zhang; Huan Chen; Xiao-Feng Lv; Chang-Gui Lu

    2012-01-01

    AIM:To investigate the feasibility and the effectiveness of ileoileostomy in the region adjacent to the ileocecal valve,which can retain the ileocecal valve in infants.METHODS:This is a retrospective review of 48 patients who underwent ileoileostomy in the region adjacent to the ileocecal valve (group 1) and 34 patients who underwent ileocecal resections and ileotransversanastomosis (group 2).Patients were monitored for the time to flatus,resumption of eating,length of hospital stay after surgery,serum total bile acid,vitamin B12 and postoperative complications.RESULTS:The time to flatus,time until resumption of eating and post-operative length of hospital stay showed no statistically significant differences between the two groups.Serum total bile acid and vitamin B12 were not significantly different between the two groups at post-operative day 1 and day 3,but were significantly decreased at 1 wk after operation in group 2.None of the patients died or suffered from stomal leak in these two groups.However,the incidence of diarrhea,intestinal infection,disturbance of acid-base balance and water-electrolytes in group 1 was lower than in group 2.CONCLUSION:Ileoileostomy in the region adjacent to the ileocecal valve is safe and results in fewer complications than ileotransversanastomosis in infants.

  19. Adjacent Segment Pathology after Anterior Cervical Fusion.

    Science.gov (United States)

    Chung, Jae Yoon; Park, Jong-Beom; Seo, Hyoung-Yeon; Kim, Sung Kyu

    2016-06-01

    Anterior cervical fusion has become a standard of care for numerous pathologic conditions of the cervical spine. However, subsequent development of clinically significant disc disease at levels adjacent to fused discs is a serious long-term complication of this procedure. As more patients live longer after surgery, it is foreseeable that adjacent segment pathology (ASP) will develop in increasing numbers of patients. Also, ASP has been studied more intensively with the recent popularity of motion preservation technologies like total disc arthroplasty. The true nature and scope of ASP remains poorly understood. The etiology of ASP is most likely multifactorial. Various factors including altered biomechanical stresses, surgical disruption of soft tissue and the natural history of cervical disc disease contribute to the development of ASP. General factors associated with disc degeneration including gender, age, smoking and sports may play a role in the development of ASP. Postoperative sagittal alignment and type of surgery are also considered potential causes of ASP. Therefore, a spine surgeon must be particularly careful to avoid unnecessary disruption of the musculoligamentous structures, reduced risk of direct injury to the disc during dissection and maintain a safe margin between the plate edge and adjacent vertebrae during anterior cervical fusion.

  20. Enteroenteroanastomosis near adjacent ileocecal valve in infants

    Science.gov (United States)

    Jiang, Wei-Wei; Xu, Xiao-Qun; Geng, Qi-Ming; Zhang, Jie; Chen, Huan; Lv, Xiao-Feng; Lu, Chang-Gui; Tang, Wei-Bing

    2012-01-01

    AIM: To investigate the feasibility and the effectiveness of ileoileostomy in the region adjacent to the ileocecal valve, which can retain the ileocecal valve in infants. METHODS: This is a retrospective review of 48 patients who underwent ileoileostomy in the region adjacent to the ileocecal valve (group 1) and 34 patients who underwent ileocecal resections and ileotransversanastomosis (group 2). Patients were monitored for the time to flatus, resumption of eating, length of hospital stay after surgery, serum total bile acid, vitamin B12 and postoperative complications. RESULTS: The time to flatus, time until resumption of eating and post-operative length of hospital stay showed no statistically significant differences between the two groups. Serum total bile acid and vitamin B12 were not significantly different between the two groups at post-operative day 1 and day 3, but were significantly decreased at 1 wk after operation in group 2. None of the patients died or suffered from stomal leak in these two groups. However, the incidence of diarrhea, intestinal infection, disturbance of acid-base balance and water-electrolytes in group 1 was lower than in group 2. CONCLUSION: Ileoileostomy in the region adjacent to the ileocecal valve is safe and results in fewer complications than ileotransversanastomosis in infants. PMID:23326139

  1. [Atmospheric adjacency effect correction of ETM images].

    Science.gov (United States)

    Liu, Cheng-yu; Chen, Chun; Zhang, Shu-qing; Gao, Ji-yue

    2010-09-01

    It is an important precondition to retrieve the ground surface reflectance exactly for improving the subsequent product of remote sensing images and the quantitative application of remote sensing. However, because the electromagnetic wave is scattered by the atmosphere during its transmission from the ground surface to the sensor, the electromagnetic wave signal of the target received by the sensor contained the signal of the background. The adjacency effect emerges. Because of the adjacency effect, the remote sensing images become blurry, and their contrast reduces. So the ground surface reflectance retrieved from the remote sensing images is also inaccurate. Finally, the quality of subsequent product of remote sensing images and the accuracy of quantitative application of remote sensing might decrease. In the present paper, according to the radiative transfer equation, the atmospheric adjacency effect correction experiment of ETM images was carried out by using the point spread function method. The result of the experiment indicated that the contrast of the corrected ETM images increased, and the ground surface reflectance retrieved from those images was more accurate.

  2. Bis{2-[(2,4,6-trimethyl-phen-yl)imino-methyl]pyrrol-1-ido}palladium(II).

    Science.gov (United States)

    Imhof, Wolfgang

    2013-02-01

    The title compound, [Pd(C(14)H(15)N(2))(2)], is a square-planar palladium complex composed of two deprotonated pyrrole-2-carbaldimine ligands coordinating a central Pd(II) atom. In the crystal, three crystallographically independent complex mol-ecules are observed, one of which is located in a general position, whereas the Pd(II) atoms of the other mol-ecules are situated on crystallographic inversion centers. The aromatic substituents at the imine N atoms in the three mol-ecules show dihedral angles of 87.6 (7)/83.64 (7), 74.3 (7) and 88.3 (7)° with respect to the corresponding PdN(4) plane.

  3. 2-(4-Methyl-phen-yl)-6-nitro-1,3-benzoxazole.

    Science.gov (United States)

    Centore, Roberto; Piccialli, Vincenzo; Tuzi, Angela

    2013-05-01

    The title compound, C14H10N2O3, is a π-conjugated mol-ecule containing a benzoxazole aromatic fused heterobicycle. The benzoxazole ring system is planar within 0.01 Å. The mol-ecule assumes an approximately flat conformation, the benzoxazole ring system forming dihedral angles of 6.52 (12) and 7.4 (3)° with the benzene ring and the nitro group, respectively. In the crystal, mol-ecules are connected by very weak C-H⋯O hydrogen inter-actions, forming chains running parallel to the a or c axes. The methyl H atoms are disordered over two sets of sites of equal occupancy rotated by 60°.

  4. Poly[[aqua-{μ4-2-[(carb-oxy-meth-yl)sulfan-yl]nicotinato-κ(4) O:O':O'':O'''}copper(II)] trihydrate].

    Science.gov (United States)

    Li, Wei-Qi

    2013-05-01

    In the polymeric title complex, {[Cu(C8H5NO4S)(H2O)]·3H2O} n , the Cu(II) cation is coordinated by one water mol-ecule and four carboxyl-ate O atoms from four 2-[(carb-oxy-meth-yl)sulfan-yl]nicotinate anions in a distorted square-pyramidal geometry. The 2-[(carb-oxy-meth-yl)sulfan-yl]nicotinate anion bridges four Cu(II) cations, forming a two-dimensional polymeric complex parallel to the bc plane. In the crystal, O-H⋯O, O-H⋯N and O-H⋯S hydrogen bonds link the complex mol-ecules and lattice water mol-ecules into a three-dimensional supra-molecular architecture.

  5. (1S,2R,7R,8S,10R)-9,9-Di-bromo-2,6,6,10-tetra-methyl-1α,2α-ep-oxy-tri-cyclo-[5.5.0.0(8,10)]dodeca-ne.

    Science.gov (United States)

    Benharref, Ahmed; El Karroumi, Jamal; El Ammari, Lahcen; Saadi, Mohamed; Berraho, Moha

    2013-01-01

    The title compound, C16H24Br2O, was synthesized from the reaction of β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzo-cyclo-heptene), which was isolated from Atlas cedar (Cedrus atlantica) essential oil, after reaction with di-bromo-carbene. The asymmetric unit contains two independent mol-ecules with similar conformations. Each mol-ecule is built up from fused six-and seven-membered rings and two three-membered rings. In both mol-ecules, the six-membered ring has an envelope conformation with the flap provided by the C atom of the ep-oxy ring, whereas the seven-membered ring displays a chair conformation. The crystal packing is governed only by van der Waals inter-actions. The absolute configuration was established from anomalous dispersion effects.

  6. (1S,3S,8R,9S,11R)-10,10-Di-bromo-3,7,7,11-tetra-methyl-tetra-cyclo-[6.5.0.0(1,3).0(9,11)]trideca-ne.

    Science.gov (United States)

    Benharref, Ahmed; El Karroumi, Jamal; El Ammari, Lahcen; Saadi, Mohamed; Berraho, Moha

    2013-01-01

    The title compound, C17H26Br2, was synthesized from β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzo-cyclo-heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The asymmetric unit contains two independent mol-ecules with similar conformations. Each mol-ecule is built up from fused six- and seven-membered rings and two appended three-membered rings. In both mol-ecules, the six-membered ring has a screw boat conformation, whereas the seven-membered ring displays a boat conformation. No specific inter-molecular inter-actions were discerned in the crystal packing.

  7. (1S,3R,8R,9S,11R)-10,10-Di-bromo-2,2-di-chloro-3,7,7,11-tetra-methyl-tetra-cyclo-[6.5.0.0(1,3).0(9,11)]trideca-ne.

    Science.gov (United States)

    Oukhrib, Abdelouahd; Benharref, Ahmed; Saadi, Mohamed; Berraho, Moha; El Ammari, Lahcen

    2013-05-01

    The title compound, C17H24Br2Cl2, was synthesized from β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzo-cyclo-heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The asymmetric unit contains two independent mol-ecules. Each mol-ecule is built up from fused six-, seven- and two three-membered rings. In both mol-ecules, the six-membered ring has a half-chair conformation, whereas the seven-membered ring displays a boat conformation. No specific inter-molecular inter-actions are noted in the crystal packing.

  8. Di-μ-acetato-μ-aqua-bis-[acetatobis(1H-benzimidazole)cobalt(II)].

    Science.gov (United States)

    Zimmermann, Iwan; Keene, Tony D; Neels, Antonia; Decurtins, Silvio

    2008-05-30

    In the title compound, [Co(2)(C(2)H(3)O(2))(4)(C(7)H(6)N(2))(4)(H(2)O)], the half-mol-ecule in the asymmetric unit is completed by a crystallographic twofold rotation axis to give the full mol-ecule. The Co(II) ions are approximately octahedrally coordinated with a cis-N(2)O(4) coordination sphere. The compound features intra-molecular O-H⋯O hydrogen bonds between the non-bridging acetate groups and the bridging water mol-ecule, and inter-molecular N-H⋯O hydrogen bonds between the acetates and amine H atoms of the benzimidazoles which determine the mol-ecular packing in the crystal structure.

  9. N-[4-(9-Chloro-quino[3,2-b]benzo[1,4]thia-zin-6-yl)but-yl]acetamide.

    Science.gov (United States)

    Jeleń, Małgorzata; Suwińska, Kinga; Pluta, Krystian; Morak-Młodawska, Beata

    2012-12-01

    In the title mol-ecule, C21H20ClN3OS, the tetra-cyclic system is close to planar [r.m.s. deviation = 0.110 (4) Å]. The dihedral angle between the quinoline ring system and the benzene ring is 178.3 (1)° and the angle between two (S-C=C-N) halves of the thia-zine ring is 173.4 (1)°. In the crystal, mol-ecules are arranged via π-π inter-actions [centroid-centroid distances = 3.603 (2)-3.739 (2) Å] into slipped stacks extending along [010]. Inter-molecular N-H⋯O hydrogen bonds link the amide groups of neighbouring mol-ecules along the stack, generating a C(4) motif. The title compound shows promising anti-proliferative and anti-cancer activity.

  10. Diaqua-bis-(perchlorato)(1,10-phenanthroline)copper(II).

    Science.gov (United States)

    Kaabi, Kamel; El Glaoui, Meher; Zeller, Matthias; Ben Nasr, Cherif

    2010-08-21

    In the title compound, [Cu(ClO(4))(2)(C(12)H(8)N(2))(H(2)O)(2)], the Cu(II) atom is coordinated in a square-planar fashion by the two N atoms of a chelating 1,10-phenanthroline ligand and by two water mol-ecules trans to the N atoms. The coordination sphere of the metal atom is augmented by O atoms of two weakly bonded perchlorate anions, thus yielding a strongly distorted CuN(2)O(4) octa-hedral environment. The crystal packing is stabilized by O-H⋯O hydrogen bonds between the water mol-ecules and the perchlorate anions. In addition, the organic mol-ecules are associated by π-π stacking inter-actions between symmetry-equivalent anti-parallel non-nitro-gen aromatic rings, with inter-planar distances of 3.543 (2) Å.

  11. (E)-2,4,6-Trimethyl-N-[(1H-pyrrol-2-yl)methyl-idene]aniline.

    Science.gov (United States)

    Imhof, Wolfgang

    2013-01-01

    The title compound, C14H16N2, is a pyrrole-2-carbaldimine ligand that shows an E conformation at the imine double bond. The dihedral angle between the rings is 78.3 (1)°. In the crystal, pairs of mol-ecules form centrosymmetric dimers [graph-set descriptor is presumably R(2)2(10)] via N-H⋯N hydrogen bonds between the pyrrole N-H group and the imine N atom of a neighbouring mol-ecule.

  12. Hexa-kis-(3-chloro-2-methyl-anilinium) cyclo-hexa-phosphate dihydrate.

    Science.gov (United States)

    Bel Haj Salah, Raoudha; Khederi, Lamia; Rzaigui, Mohamed

    2014-01-01

    In the organic/inorganic salt hydrate, 6C7H9ClN(+)·P6O18 (6-)·2H2O, the cyclo-hexa-phosphate anion resides on an inversion centre. The asymmetric unit consists of three cations, one half-anion and a water mol-ecule. In the crystal, the water mol-ecules and the [P6O18](6-) anions are linked by O-H⋯O hydrogen bonds, generating infinite layers parallel to the ab plane. These layers are inter-connected by the organic cations through N-H⋯O hydrogen bonds.

  13. (E)-1-{4-[Bis(4-meth-oxy-phen-yl)meth-yl]piperazin-1-yl}-3-(4-eth-oxy-3-meth-oxy-phen-yl)prop-2-en-1-one.

    Science.gov (United States)

    Zhong, Yan; Zhang, Xiao-Ping; Wu, Bin

    2012-04-01

    In the mol-ecule of the title compound, C(31)H(36)N(2)O(5), the piperazine ring displays a chair conformation. The dihedral angle between the benzene rings of the bis-(4-meth-oxy-phen-yl)methyl group is 83.42 (15)°. In the crystal, centrosymmetric-ally related mol-ecules are linked through pairs of C-H⋯O hydrogen bonds into dimers, generating an R(2) (2)(10) ring motif. The dimers are further connected into chains parallel to [2-10] by C-H⋯O hydrogen bonds involving the meth-oxy groups.

  14. Clarithromycin monohydrate: a synchrotron X-ray powder study.

    Science.gov (United States)

    Noguchi, Shuji; Fujiki, Sadahiro; Iwao, Yasunori; Miura, Keiko; Itai, Shigeru

    2012-03-01

    In the crystal structure of the title compound, clarithromycin (CAM) monohydrate, C(38)H(69)NO(13)·H(2)O, the water mol-ecule behaves as a proton donor and is hydrogen bonded to the hy-droxy O atom of the CAM cladinose ring. The hy-droxy O atom also behaves as a proton donor, forming an inter-molecular hydrogen bond with one of the hy-droxy groups of the 14-membered aglycone ring. The CAM mol-ecules are linked through these hydrogen bonds into chains running parallel to the c axis.

  15. 4-{[Bis(2-hy-droxy-eth-yl)amino]-meth-yl}-6-meth-oxy-2H-chromen-2-one.

    Science.gov (United States)

    Naik, Reshma; Sankolli, Ravish; Anil Kumar, G N; Row, T N Guru; Kulkarni, Manohar V

    2012-08-01

    In the title compound, C(15)H(19)NO(5), an intra-molecular O-H⋯O hydrogen bond links the hy-droxy-ethyl side chains, forming a seven-membered ring. In the crystal, mol-ecules are linked into chains via O-H⋯O hydrogen bonds along the b axis. Further, mol-ecules are linked by weak inter-molecular C-H⋯O and π-π stacking inter-actions [centroid-centroid distance = 3.707 (4) Å].

  16. 3-Ethyl-4-hy-droxy-8-meth-oxy-quinolin-2(1H)-one.

    Science.gov (United States)

    Kafka, Stanislav; Pevec, Andrej; Proisl, Karel; Kimmel, Roman; Košmrlj, Janez

    2012-11-01

    In the title compound, C(12)H(13)NO(3), the quinoline ring system is approximately planar with a maximum deviation from the least-squares plane of 0.058 (2) Å. In the crystal, N-H⋯O and O-H⋯O hydrogen bonds link the mol-ecules into chains running along the b-axis direction. The chains also feature π-π inter-actions between pyridine and benzene rings of inversion-related mol-ecules [centroid-centroid distance = 3.609 (2) Å].

  17. Tetra-aqua-bis-{3-carb-oxy-5-[(4-carb-oxy-phen-yl)diazen-yl]benzoato-κO}cobalt(II) dihydrate.

    Science.gov (United States)

    Bai, Liang; Zhao, Jun

    2011-12-01

    In the title complex, [Co(C(15)H(9)N(2)O(6))(2)(H(2)O)(4)]·2H(2)O, the Co(II) ion is located on an inversion center and is coordinated by two monodentate 3-carb-oxy-5-[(4-carb-oxy-phen-yl)diazen-yl]benzo-ate ligands and four water mol-ecules in a distorted octa-hedral geometry. In the crystal, inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional supra-molecular network.

  18. (1S,2R,3S,6S,7R)-3,7,11,11-Tetra-methyl-6,7-epoxybi-cyclo-[5.4.0]undecane-2-ol.

    Science.gov (United States)

    Loubidi, Mohamed; Benharref, Ahmed; El Ammari, Lahcen; Saadi, Mohamed; Berraho, Moha

    2014-05-01

    The title compound, C15H26O2, was synthesized from β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzo-cyclo-heptene), which was isolated from the Atlas cedar (cedrus atlantica). The mol-ecule is built up from a seven-membered ring to which a six- and a three-membered ring are fused. The seven- and six-membered rings each have a twist-boat conformation. In the crystal, O-H⋯O hydrogen bonds link the mol-ecules into zigzag chains running along the b-axis direction.

  19. 1-{3-[1-(Hydroxyimino)ethyl]-4-methyl-1H-pyrazol-5-yl}ethanone.

    Science.gov (United States)

    Malinkin, Sergey; Penkova, Larysa; Pavlenko, Vadim A; Haukka, Matti; Pavlova, Svetlana V

    2011-10-01

    In the title compound, C(8)H(11)N(3)O(2), the oxime and the acetyl groups adopt a transoid conformation, while the pyrazole H atom is localized in the proximity of the acetyl group and is cis with respect to the acetyl O atom. In the crystal, dimers are formed as the result of hydrogen-bonding inter-actions involving the pyrazole NH group of one mol-ecule and the carbonyl O atom of another. The dimers are associated into sheets via O-H⋯N hydrogen bonds involving the oxime hydroxyl and the unprotonated pyrazole N atom, generating a macrocyclic motif with six mol-ecules.

  20. Crystal structure of tetra-kis-[μ2-2-(di-methyl-amino)-ethano-lato-κ(3) N,O:O]di-μ3-hydroxido-di-thio-cyanato-κ(2) N-dichromium(III)dilead(II) di-thio-cyanate aceto-nitrile monosolvate.

    Science.gov (United States)

    Rusanova, Julia A; Semenaka, Valentyna V; Omelchenko, Irina V

    2016-04-01

    The tetra-nuclear complex cation of the title compound, [Cr2Pb2(NCS)2(OH)2(C4H10NO)4](SCN)2·CH3CN, lies on an inversion centre. The main structural feature of the cation is a distorted seco-norcubane Pb2Cr2O6 cage with a central four-membered Cr2O2 ring. The Cr(III) ion is coordinated in a distorted octa-hedron, which involves two N atoms of one bidentate ligand and one thio-cyanate anion, two μ2-O atoms of 2-(di-methyl-amino)-ethano-late ligands and two μ3-O atoms of hydroxide ions. The coordination geometry of the Pb(II) ion is a distorted disphenoid, which involves one N atom, two μ2-O atoms and one μ3-O atom. In addition, weak Pb⋯S inter-actions involving the coordinating and non-coordinating thio-cyanate anions are observed. In the crystal, the complex cations are linked through the thio-cyanate anions via the Pb⋯S inter-actions and O-H⋯N hydrogen bonds into chains along the c axis. The chains are further linked together via S⋯S contacts. The contribution of the disordered solvent aceto-nitrile mol-ecule was removed with the SQUEEZE [Spek (2015 ▸). Acta Cryst. C71, 9-18] procedure in PLATON. The solvent is included in the reported mol-ecular formula, weight and density.

  1. Regularity extraction from non-adjacent sounds

    Directory of Open Access Journals (Sweden)

    Alexandra eBendixen

    2012-05-01

    Full Text Available The regular behavior of sound sources helps us to make sense of the auditory environment. Regular patterns may, for instance, convey information on the identity of a sound source (such as the acoustic signature of a train moving on the rails. Yet typically, this signature overlaps in time with signals emitted from other sound sources. It is generally assumed that auditory regularity extraction cannot operate upon this mixture of signals because it only finds regularities between adjacent sounds. In this view, the auditory environment would be grouped into separate entities by means of readily available acoustic cues such as separation in frequency and location. Regularity extraction processes would then operate upon the resulting groups. Our new experimental evidence challenges this view. We presented two interleaved sound sequences which overlapped in frequency range and shared all acoustic parameters. The sequences only differed in their underlying regular patterns. We inserted deviants into one of the sequences to probe whether the regularity was extracted. In the first experiment, we found that these deviants elicited the mismatch negativity (MMN component. Thus the auditory system was able to find the regularity between the non-adjacent sounds. Regularity extraction was not influenced by sequence cohesiveness as manipulated by the relative duration of tones and silent inter-tone-intervals. In the second experiment, we showed that a regularity connecting non-adjacent sounds was discovered only when the intervening sequence also contained a regular pattern, but not when the intervening sounds were randomly varying. This suggests that separate regular patterns are available to the auditory system as a cue for identifying signals coming from distinct sound sources. Thus auditory regularity extraction is not necessarily confined to a processing stage after initial sound grouping, but may precede grouping when other acoustic cues are unavailable.

  2. Adjacent-level arthroplasty following cervical fusion.

    Science.gov (United States)

    Rajakumar, Deshpande V; Hari, Akshay; Krishna, Murali; Konar, Subhas; Sharma, Ankit

    2017-02-01

    OBJECTIVE Adjacent-level disc degeneration following cervical fusion has been well reported. This condition poses a major treatment dilemma when it becomes symptomatic. The potential application of cervical arthroplasty to preserve motion in the affected segment is not well documented, with few studies in the literature. The authors present their initial experience of analyzing clinical and radiological results in such patients who were treated with arthroplasty for new or persistent arm and/or neck symptoms related to neural compression due to adjacent-segment disease after anterior cervical discectomy and fusion (ACDF). METHODS During a 5-year period, 11 patients who had undergone ACDF anterior cervical discectomy and fusion (ACDF) and subsequently developed recurrent neck or arm pain related to adjacent-level cervical disc disease were treated with cervical arthroplasty at the authors' institution. A total of 15 devices were implanted (range of treated levels per patient: 1-3). Clinical evaluation was performed both before and after surgery, using a visual analog scale (VAS) for pain and the Neck Disability Index (NDI). Radiological outcomes were analyzed using pre- and postoperative flexion/extension lateral radiographs measuring Cobb angle (overall C2-7 sagittal alignment), functional spinal unit (FSU) angle, and range of motion (ROM). RESULTS There were no major perioperative complications or device-related failures. Statistically significant results, obtained in all cases, were reflected by an improvement in VAS scores for neck/arm pain and NDI scores for neck pain. Radiologically, statistically significant increases in the overall lordosis (as measured by Cobb angle) and ROM at the treated disc level were observed. Three patients were lost to follow-up within the first year after arthroplasty. In the remaining 8 cases, the duration of follow-up ranged from 1 to 3 years. None of these 8 patients required surgery for the same vertebral level during the follow

  3. 6-Methyl-2-oxo-N-(quinolin-6-yl)-2H-chromene-3-carboxamide: crystal structure and Hirshfeld surface analysis.

    Science.gov (United States)

    Gomes, Lígia R; Low, John Nicolson; Fonseca, André; Matos, Maria João; Borges, Fernanda

    2016-08-01

    The title coumarin derivative, C20H14N2O3, displays intra-molecular N-H⋯O and weak C-H⋯O hydrogen bonds, which probably contribute to the approximate planarity of the mol-ecule [dihedral angle between the coumarin and quinoline ring systems = 6.08 (6)°]. The supra-molecular structures feature C-H⋯O hydrogen bonds and π-π inter-actions, as confirmed by Hirshfeld surface analyses.

  4. Kauffman's adjacent possible in word order evolution

    CERN Document Server

    Ferrer-i-Cancho, Ramon

    2015-01-01

    Word order evolution has been hypothesized to be constrained by a word order permutation ring: transitions involving orders that are closer in the permutation ring are more likely. The hypothesis can be seen as a particular case of Kauffman's adjacent possible in word order evolution. Here we consider the problem of the association of the six possible orders of S, V and O to yield a couple of primary alternating orders as a window to word order evolution. We evaluate the suitability of various competing hypotheses to predict one member of the couple from the other with the help of information theoretic model selection. Our ensemble of models includes a six-way model that is based on the word order permutation ring (Kauffman's adjacent possible) and another model based on the dual two-way of standard typology, that reduces word order to basic orders preferences (e.g., a preference for SV over VS and another for SO over OS). Our analysis indicates that the permutation ring yields the best model when favoring pa...

  5. Detecting Adjacent Relativity of Engineering Drawing Entities with Container Window

    Institute of Scientific and Technical Information of China (English)

    林福严; 邱友申; 秦吉胜

    2001-01-01

    Automatic recognition and interpretation of engineering drawing plays an important role in computer aided engineering. Detecting the positional relation between entities is an important topic in this research field. In this paper the concepts of adjacent relativity and container window of drawing entities were proposed. By means of container window, the adjacent irrelative entities can be detected quickly and effectively, which speeds up the process of adjacent relativity detection. Meanwhile, the algorithm of adjacent relativity detection was discussed.

  6. Exchange coupling between laterally adjacent nanomagnets

    Science.gov (United States)

    Dey, H.; Csaba, G.; Bernstein, G. H.; Porod, W.

    2016-09-01

    We experimentally demonstrate exchange-coupling between laterally adjacent nanomagnets. Our results show that two neighboring nanomagnets that are each antiferromagnetically exchange-coupled to a common ferromagnetic bottom layer can be brought into strong ferromagnetic interaction. Simulations show that interlayer exchange coupling effectively promotes ferromagnetic alignment between the two nanomagnets, as opposed to antiferromagnetic alignment due to dipole-coupling. In order to experimentally demonstrate the proposed scheme, we fabricated arrays of pairs of elongated, single-domain nanomagnets. Magnetic force microscopy measurements show that most of the pairs are ferromagnetically ordered. The results are in agreement with micromagnetic simulations. The presented scheme can achieve coupling strengths that are significantly stronger than dipole coupling, potentially enabling far-reaching applications in Nanomagnet Logic, spin-wave devices and three-dimensional storage and computing.

  7. 1-(3-Bromo-2-thien-yl)ethanone.

    Science.gov (United States)

    Mahendra, M; Vivek, H K; Gaonkar, S L; Priya, B S; Nanjunda Swamy, S

    2010-09-11

    In the title compound, C(6)H(5)BrOS, the non-H and aromatic H atoms lie on a crystallographic mirror plane. In the crystal, mol-ecules are linked into chains propagating along the c axis by inter-molecular C-H⋯O hydrogen bonds.

  8. N-(2-Chloro-phen-yl)-4-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-12-01

    In the title compound, C12H9ClN2O4S, the dihedral angle between the benzene rings is 70.60 (11)°. An intra-molecular N-H⋯Cl contact occurs. In the crystal, mol-ecules form inversion dimers via pairs of N-H⋯O hydrogen bonds.

  9. N-(3-Chloro-benzo-yl)-3-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Suchetan, P A; Foro, Sabine; Gowda, B Thimme

    2012-01-01

    In the title compound, C(13)H(9)ClN(2)O(5)S, the dihedral angle between the two benzene rings is 83.5 (1)°. In the crystal, mol-ecules are linked via N-H⋯O(S) hydrogen bonds into helical chains running along the b axis.

  10. N-(2-Methyl-phen-yl)-4-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-09-01

    In the title compound, C(13)H(12)N(2)O(4)S, the dihedral angle between the planes of the rings is 51.11 (10)°. In the crystal, mol-ecules are linked into inversion dimers through pairs of N-H⋯O(S) hydrogen bonds.

  11. N-Benzoyl-3-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Suchetan, P A; Foro, Sabine; Gowda, B Thimme

    2011-12-01

    In the title compound, C(13)H(10)N(2)O(5)S, the dihedral angle between the phenyl and benzene rings is 86.7 (1)°. In the crystal, mol-ecules are linked into zigzag C(4) chains running along the b axis via N-H⋯O hydrogen bonds.

  12. 3-Acetyl-1-(2,3-dichloro-phen-yl)thio-urea.

    Science.gov (United States)

    Gowda, B Thimme; Foro, Sabine; Kumar, Sharatha

    2012-08-01

    In the crystal structure of the title compound, C(9)H(8)Cl(2)N(2)OS, there are two mol-ecules in the asymmetric unit which are connected by a pair of N-H⋯S hydrogen bonds. An intra-molecular N-H⋯O hydrogen bond stabilizes the mol-ecular conformation of each molecule.

  13. N-(4-Methyl-phenyl-sulfon-yl)maleamic acid.

    Science.gov (United States)

    Purandara, H; Foro, Sabine; Gowda, B Thimme

    2012-08-01

    In the title compound, C(11)H(11)NO(5)S, the dihedral angle between the benzene ring and the amide group is 76.88 (6)°. In the crystal, N-H⋯O(S) and O-H⋯O hydrogen bonds connect the mol-ecules into hydrogen-bonded layers perpendicular to the a axis.

  14. 4-Nitro-N-phenyl-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-10-01

    In the title compound, C(12)H(10)N(2)O(4)S, the dihedral angle between the aromatic rings is 36.19 (18)°. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into C(4) chains running along the a axis.

  15. N-(4-Chloro-phen-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-08-01

    In the title compound, C(12)H(9)ClN(2)O(4)S, the dihedral angle between the aromatic rings is 70.27 (8)°. In the crystal, mol-ecules are linked by pairs of N-H⋯O(S) hydrogen bonds, forming inversion dimers.

  16. N-(4-Chloro-phen-yl)-4-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2013-01-01

    In the title compound, C12H9ClN2O4S, the dihedral angle between the benzene rings is 31.4 (2)°. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into C(4) chains running along the a-axis direction.

  17. Crystals in crystals

    DEFF Research Database (Denmark)

    Christensen, Claus H.; Schmidt, I.; Carlsson, A.;

    2005-01-01

    A major factor governing the performance of catalytically active particles supported on a zeolite carrier is the degree of dispersion. It is shown that the introduction of noncrystallographic mesopores into zeolite single crystals (silicalite-1, ZSM-5) may increase the degree of particle dispersion...... of the zeolite particles, particularly after thermal treatment. When using mesoporous zeolites, the particles were evenly distributed throughout the mesopore system of the zeolitic support, even after calcination, leading to nanocrystals within mesoporous zeolite single crystals....

  18. Interaction between Adjacent Lightning Discharges in Clouds

    Institute of Scientific and Technical Information of China (English)

    WANG Yanhui; ZHANG Guangshu; ZHANG Tong; LI Yajun; WU Bin; ZHANG Tinglong

    2013-01-01

    Using a 3D lightning radiation source locating system (LLS),three pairs of associated lightning discharges (two or more adjacent lightning discharges following an arbitrary rule that their space-gap was less than 10 km and their time-gap was less than 800 ms) were observed,and the interaction between associated lightning discharges was analyzed.All these three pairs of associated lightning discharges were found to involve three or more charge regions (the ground was considered as a special charge region).Moreover,at least one charge region involved two lightning discharges per pair of associated lightning discharges.Identified from electric field changes,the subsequent lightning discharges were suppressed by the prior lightning discharges.However,it is possible that the prior lightning discharge provided a remaining discharge channel to facilitate the subsequent lightning discharge.The third case provided evidence of this possibility.Together,the results suggested that,if the charges in the main negative charge region can be consumed using artificial lightning above the main negative charge regions,lightning accidents on the ground could be greatly reduced,on the condition that the height of the main negative charge region and the charge intensity of the lower positive charge region are suitable.

  19. Crystal structure of [NaZn(BTC)(H2O)4]·1.5H2O (BTC = benzene-1,3,5-tri-carb-oxy-l-ate): a heterometallic coordination compound.

    Science.gov (United States)

    Ni, Min; Li, Quanle; Chen, Hao; Li, Shengqing

    2015-07-01

    The title coordination polymer, poly[[μ-aqua-tri-aqua-(μ3-benzene-1,3,5-tri-carboxyl-ato)sodiumzinc] sesquihydrate], {[NaZn(C9H3O6)(H2O)4]·1.5H2O} n , was obtained in ionic liquid microemulsion at room temperture by the reaction of benzene-1,3,5-tri-carb-oxy-lic acid (H3BTC) with Zn(NO3)2·6H2O in the presence of NaOH. The asymmetric unit comprises two Na(+) ions (each located on an inversion centre), one Zn(2+) ion, one BTC ligand, four coordinating water mol-ecules and two solvent water molecules, one of which is disordered about an inversion centre and shows half-occupation. The Zn(2+) cation is five-coordinated by two carboxyl-ate O atoms from two different BTC ligands and three coordinating H2O mol-ecules; the Zn-O bond lengths are in the range 1.975 (2)-2.058 (3) Å. The Na(+) cations are six-coordinated but have different arrangements of the ligands: one is bound to two carboxyl-ate O atoms of two BTC ligands and four O atoms from four coordinating H2O mol-ecules while the other is bound by four carboxyl-ate O atoms from four BTC linkers and two O atoms of coordinating H2O mol-ecules. The completely deprotonated BTC ligand acts as a bridging ligand binding the Zn(2+) atom and Na(+) ions, forming a layered structure extending parallel to (100). An intricate network of O-H⋯O hydrogen bonds is present within and between the layers.

  20. Crystal science fundamentals

    OpenAIRE

    Ramachandran, V.; Halfpenny, PJ; Roberts, KJ

    2017-01-01

    The fundamentals of crystal science notably crystallography, crystal chemistry, crystal defects, crystal morphology and the surface chemistry of crystals are introduced with particular emphasis on organic crystals.

  1. Analysis of adjacent segment reoperation after lumbar total disc replacement

    OpenAIRE

    Rainey, Scott; Blumenthal, Scott L.; Zigler, Jack E.; Guyer, Richard D.; Ohnmeiss, Donna D.

    2012-01-01

    Background Fusion has long been used for treating chronic back pain unresponsive to nonoperative care. However, potential development of adjacent segment degeneration resulting in reoperation is a concern. Total disc replacement (TDR) has been proposed as a method for addressing back pain and preventing or reducing adjacent segment degeneration. The purpose of the study was to determine the reoperation rate at the segment adjacent to a level implanted with a lumbar TDR and to analyze the pre-...

  2. Crystal structure of cafenstrole

    Directory of Open Access Journals (Sweden)

    Gihaeng Kang

    2015-08-01

    Full Text Available The title compound (systematic name: N,N-diethyl-3-mesitylsulfonyl-1H-1,2,4-triazole-1-carboxamide, C16H22N4O3S, is a triazole herbicide. The dihedral angle between the planes of the triazole and benzene ring planes is 88.14 (10°. In the crystal, C—H...O hydrogen bonds and weak C—H...π interactions link adjacent molecules, forming one-dimensional chains along the a axis.

  3. Crystal structure of pseudoguainolide

    Directory of Open Access Journals (Sweden)

    Noureddine Beghidja

    2015-03-01

    Full Text Available The lactone ring in the title molecule, C15H22O3 (systematic name: 3,4a,8-trimethyldodecahydroazuleno[6,5-b]furan-2,5-dione, assumes an envelope conformation with the methine C atom adjacent to the the methine C atom carrying the methyl substituent being the flap atom. The other five-membered ring adopts a twisted conformation with the twist being about the methine–methylene C—C bond. The seven-membered ring is based on a twisted boat conformation. No specific interactions are noted in the the crystal packing.

  4. PIV Measurements and Mechanisms of Adjacent Synthetic Jets Interactions

    Institute of Scientific and Technical Information of China (English)

    LUO Zhen-Bing; XIA Zhi-Xun

    2008-01-01

    Interactions of adjacent synthetic jet actuators with varying relative amplitude and the relative phase of driving voltage are measured using a particle image velocimetry(PIV).Varying relative amplitude or relative phase of driving voltage of the adjacent actuators vectors the direction of the ensuing merged jet of the adjacent synthetic jets.The vectoring mechanism of the adjacent vortex pairs,attract-impact causing deflection(AICD),is provided to explain why the merged jet is generally vectored to the side of the phase-leading synthetic jet or the synthetic jet with higher driving voltage.

  5. Bis(2,2'-bipyridine)[1,9-bis(diphenylphos-phanyl)-1,2,3,4,6,7,8,9-octahydropyrim-ido[1,2-a]pyrimidin-5-ium]ruthenium(II) hexa-fluorido-phosphate dibromide di-chloro-methane disolvate monohydrate.

    Science.gov (United States)

    Shang, Congcong; Vendier, Laure; Sutra, Pierre; Igau, Alain

    2013-11-06

    In the cation of the title complex, [Ru(C31H32N3P2)(C10H8N2)2](PF6)(Br)2·2CH2Cl2·H2O, the ruthenium ion is coordinated in a distorted octa-hedral geometry by two 2,2'-bi-pyridine (bpy) ligands and a chelating cationic N-di-phenyl-phosphino-1,3,4,6,7,8-hexa-hydro-2-pyrimido[1,2-a]pyrimidine [(PPh2)2-hpp] ligand. The tricationic charge of the complex is balanced by two bromide and one hexa-fluorido-phosphate counter-anions. The compound crystallized with two mol-ecules of di-chloro-methane (one of which is equally disordered about a Cl atom) and a water mol-ecule. In the crystal, one of the Br anions bridges two water mol-ecules via O-H⋯Br hydrogen bonds, forming a centrosymmetric diamond-shaped R (4) 2(8) motif. The cation and anions and the solvent mol-ecules are linked via C-H⋯F, C-H⋯Br, C-H⋯Cl and C-H⋯O hydrogen bonds, forming a three-dimensional network.

  6. Study on Optimization of Phase Offset at Adjacent Intersections

    Directory of Open Access Journals (Sweden)

    Yuanli GU

    2010-11-01

    Full Text Available Optimization of the phase offset at adjacent intersections is the key parameter regarding coordinated control of traffic signal for adjacent intersections, which decides the effect of the coordinated control for adjacent intersections. According to characters of saturated traffic flow of Chinese urban road, this thesis establishes a model for optimization of phase offset for adjacent interactions and finds a solution from such model by adopting genetic algorithm. The model is verified by actual traffic flow datum of two adjacent signal intersections on Changan Avenue. Then a comparison is made between the optimization result of such model and that of the existing mathematical method and SYNCHRO model, which indicates that the model established by this thesis can reduce the delay suffered by vehicles at the intersections and increase the traffic efficiency of the intersections.

  7. Manufacturing method of photonic crystal

    Science.gov (United States)

    Park, In Sung; Lee, Tae Ho; Ahn, Jin Ho; Biswas, Rana; Constant, Kristen P.; Ho, Kai-Ming; Lee, Jae-Hwang

    2013-01-29

    A manufacturing method of a photonic crystal is provided. In the method, a high-refractive-index material is conformally deposited on an exposed portion of a periodic template composed of a low-refractive-index material by an atomic layer deposition process so that a difference in refractive indices or dielectric constants between the template and adjacent air becomes greater, which makes it possible to form a three-dimensional photonic crystal having a superior photonic bandgap. Herein, the three-dimensional structure may be prepared by a layer-by-layer method.

  8. Loading effects of anterior cervical spine fusion on adjacent segments

    Directory of Open Access Journals (Sweden)

    Chien-Shiung Wang

    2012-11-01

    Full Text Available Adjacent segment degeneration typically follows anterior cervical spine fusion. However, the primary cause of adjacent segment degeneration remains unknown. Therefore, in order to identify the loading effects that cause adjacent segment degeneration, this study examined the loading effects to superior segments adjacent to fused bone following anterior cervical spine fusion. The C3–C6 cervical spine segments of 12 sheep were examined. Specimens were divided into the following groups: intact spine (group 1; and C5–C6 segments that were fused via cage-instrumented plate fixation (group 2. Specimens were cycled between 20° flexion and 15° extension with a displacement control of 1°/second. The tested parameters included the range of motion (ROM of each segment, torque and strain on both the body and inferior articular process at the superior segments (C3–C4 adjacent to the fused bone, and the position of the neutral axis of stress at under 20° flexion and 15° extension. Under flexion and Group 2, torque, ROM, and strain on both the bodies and facets of superior segments adjacent to the fused bone were higher than those of Group 1. Under extension and Group 2, ROM for the fused segment was less than that of Group 1; torque, ROM, and stress on both the bodies and facets of superior segments adjacent to the fused bone were higher than those of Group 1. These analytical results indicate that the muscles and ligaments require greater force to achieve cervical motion than the intact spine following anterior cervical spine fusion. In addition, ROM and stress on the bodies and facets of the joint segments adjacent to the fused bone were significantly increased. Under flexion, the neutral axis of the stress on the adjacent segment moved backward, and the stress on the bodies of the segments adjacent to the fused bone increased. These comparative results indicate that increased stress on the adjacent segments is caused by stress-shielding effects

  9. Crystal structure of bis-(3-bromo-mesit-yl)(quino-lin-1-ium-8-yl)boron(III) tribromide.

    Science.gov (United States)

    Son, Jungho; Tamang, Sem Raj; Hoefelmeyer, James D

    2015-09-01

    The title compound, C27H26.82BBr2.18N(+)·Br3 (-), is a cationic tri-aryl-borane isolated as its tribromide salt. The aryl substituents include a protonated 8-quinolyl group and two 3-bromo-mesityl groups. The mol-ecule was prepared on combination of 3:1 Br2 and dimesit-yl(quinolin-8-yl)borane in hexa-nes. The refinement of the structure indicated a degree of 'over-bromination' (beyond two bromine atoms) for the cation. There are two tribromide ions in the asymmetric unit, both completed by crystallographic inversion symmetry.

  10. Gas samples of Afghanistan and adjacent areas (gasafg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile contains points that describe the location of gas samples collected in Afghanistan and adjacent areas and the results of organic geochemical analysis.

  11. Ollier's disease in association with adjacent fibromatosis

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ismail, Khalid; Torreggiani, William C.; Munk, Peter L. [Department of Radiology, Vancouver General Hospital, University of British Columbia, 899 West l2th Avenue, Vancouver, BC (Canada); O' Connell, John X.; Nicolaou, Savvakis [Department of Pathology, Vancouver General Hospital, University of British Columbia, 899 West l2th Avenue, Vancouver, BC (Canada); Masri, Bassam A. [Department of Orthopaedics, Vancouver General Hospital, University of British Columbia, 899 West l2th Avenue, Vancouver, BC (Canada)

    2002-08-01

    Ollier's disease (enchondromatosis) is a nonhereditary disorder of mesodermal dysplasia. It is characterized by the presence of multiple enchondromas that typically affect the metaphyseal ends of bones. The association of Ollier's disease with adjacent fibromatosis has, to our knowledge, not been previously described. We report a case of Ollier's disease in association with soft tissue fibromatosis adjacent to the involved upper arm. (orig.)

  12. Axion Crystals

    CERN Document Server

    Ozaki, Sho

    2016-01-01

    The low-energy effective theories for gapped insulators are classified by three parameters: permittivity $\\epsilon$, permeability $\\mu$, and theta angle $\\theta$. Crystals with periodic $\\epsilon$ are known as photonic crystals. We here study the band structure of photons in a new type of crystals with periodic $\\theta$ (modulo $2\\pi$) in space, which we call the axion crystals. We find that the axion crystals have a number of new properties that the usual photonic crystals do not possess, such as the helicity-dependent photonic band gaps and the nonrelativistic gapless dispersion relation at small momentum. We briefly discuss possible realizations of axion crystals in condensed matter systems as well as high-energy physics.

  13. Crystal structure and Hirshfeld surface analysis of 1-carb-oxy-2-(3,4-di-hydroxy-phen-yl)ethan-1-aminium chloride 2-ammonio-3-(3,4-di-hydroxy-phen-yl)propano-ate: a new polymorph of l-dopa HCl and isotypic with its bromide counterpart.

    Science.gov (United States)

    Kathiravan, Perumal; Balakrishnan, Thangavelu; Venkatesan, Perumal; Ramamurthi, Kandasamy; Percino, María Judith; Thamotharan, Subbiah

    2016-11-01

    The title mol-ecular salt, C9H12NO4(+)·Cl(-)·C9H11NO4, is isotypic with that of the bromide counterpart [Kathiravan et al. (2016 ▸). Acta Cryst. E72, 1544-1548]. The title salt is a second monoclinic polymorph of the l-dopa HCl structure reported earlier in the monoclinic space group P21 [Jandacek & Earle (1971 ▸). Acta Cryst. B27, 841-845; Mostad & Rømming (1974 ▸). Acta Chemica Scand. B28, 1161-1168]. In the title compound, monoclinic space group I2, one of the dopa mol-ecules has a positive charge with a protonated α-amino group and the α-carb-oxy-lic acid group uncharged, while the second dopa mol-ecule has a neutral charge, the α-amino group is protonated and the α-carb-oxy-lic acid is deprotonated. In the previously reported form, a single dopa mol-ecule is observed in which the α-amino group is protonated and the α-carb-oxy-lic acid group is uncharged. The invariant and variations of various types of inter-molecular inter-actions present in these two forms of dopa HCl structures are discussed with the aid of two-dimensional fingerprint plots.

  14. RNA Crystallization

    Science.gov (United States)

    Golden, Barbara L.; Kundrot, Craig E.

    2003-01-01

    RNA molecules may be crystallized using variations of the methods developed for protein crystallography. As the technology has become available to syntheisize and purify RNA molecules in the quantities and with the quality that is required for crystallography, the field of RNA structure has exploded. The first consideration when crystallizing an RNA is the sequence, which may be varied in a rational way to enhance crystallizability or prevent formation of alternate structures. Once a sequence has been designed, the RNA may be synthesized chemically by solid-state synthesis, or it may be produced enzymatically using RNA polymerase and an appropriate DNA template. Purification of milligram quantities of RNA can be accomplished by HPLC or gel electrophoresis. As with proteins, crystallization of RNA is usually accomplished by vapor diffusion techniques. There are several considerations that are either unique to RNA crystallization or more important for RNA crystallization. Techniques for design, synthesis, purification, and crystallization of RNAs will be reviewed here.

  15. Protein Crystallization

    Science.gov (United States)

    Chernov, Alexander A.

    2005-01-01

    Nucleation, growth and perfection of protein crystals will be overviewed along with crystal mechanical properties. The knowledge is based on experiments using optical and force crystals behave similar to inorganic crystals, though with a difference in orders of magnitude in growing parameters. For example, the low incorporation rate of large biomolecules requires up to 100 times larger supersaturation to grow protein, rather than inorganic crystals. Nucleation is often poorly reproducible, partly because of turbulence accompanying the mixing of precipitant with protein solution. Light scattering reveals fluctuations of molecular cluster size, its growth, surface energies and increased clustering as protein ages. Growth most often occurs layer-by-layer resulting in faceted crystals. New molecular layer on crystal face is terminated by a step where molecular incorporation occurs. Quantitative data on the incorporation rate will be discussed. Rounded crystals with molecularly disordered interfaces will be explained. Defects in crystals compromise the x-ray diffraction resolution crucially needed to find the 3D atomic structure of biomolecules. The defects are immobile so that birth defects stay forever. All lattice defects known for inorganics are revealed in protein crystals. Contribution of molecular conformations to lattice disorder is important, but not studied. This contribution may be enhanced by stress field from other defects. Homologous impurities (e.g., dimers, acetylated molecules) are trapped more willingly by a growing crystal than foreign protein impurities. The trapped impurities induce internal stress eliminated in crystals exceeding a critical size (part of mni for ferritin, lysozyme). Lesser impurities are trapped from stagnant, as compared to the flowing, solution. Freezing may induce much more defects unless quickly amorphysizing intracrystalline water.

  16. Computational crystallization.

    Science.gov (United States)

    Altan, Irem; Charbonneau, Patrick; Snell, Edward H

    2016-07-15

    Crystallization is a key step in macromolecular structure determination by crystallography. While a robust theoretical treatment of the process is available, due to the complexity of the system, the experimental process is still largely one of trial and error. In this article, efforts in the field are discussed together with a theoretical underpinning using a solubility phase diagram. Prior knowledge has been used to develop tools that computationally predict the crystallization outcome and define mutational approaches that enhance the likelihood of crystallization. For the most part these tools are based on binary outcomes (crystal or no crystal), and the full information contained in an assembly of crystallization screening experiments is lost. The potential of this additional information is illustrated by examples where new biological knowledge can be obtained and where a target can be sub-categorized to predict which class of reagents provides the crystallization driving force. Computational analysis of crystallization requires complete and correctly formatted data. While massive crystallization screening efforts are under way, the data available from many of these studies are sparse. The potential for this data and the steps needed to realize this potential are discussed.

  17. Early verb constructions in French: adjacency on the left edge.

    Science.gov (United States)

    Veneziano, Edy; Clark, Eve V

    2016-11-01

    Children acquiring French elaborate their early verb constructions by adding adjacent morphemes incrementally at the left edge of core verbs. This hypothesis was tested with 2657 verb uses from four children between 1;3 and 2;7. Consistent with the Adjacency Hypothesis, children added clitic subjects first only to present tense forms (as in il saute 'he jumps'); modals to infinitives (as in faut sauter 'has to jump'); and auxiliaries to past participles (as in a sauté 'has jumped'). Only after this did the children add subjects to the left of a modal or auxiliary, as in elle veut sauter 'she wants to jump', or elle a sauté 'she has jumped'. The order in which these elements were added, and the development in the frequencies of the constructions, all support the predictions of the Adjacency Hypothesis for left edge development in early verb constructions.

  18. Laplacian versus adjacency matrix in quantum walk search

    Science.gov (United States)

    Wong, Thomas G.; Tarrataca, Luís; Nahimov, Nikolay

    2016-10-01

    A quantum particle evolving by Schrödinger's equation contains, from the kinetic energy of the particle, a term in its Hamiltonian proportional to Laplace's operator. In discrete space, this is replaced by the discrete or graph Laplacian, which gives rise to a continuous-time quantum walk. Besides this natural definition, some quantum walk algorithms instead use the adjacency matrix to effect the walk. While this is equivalent to the Laplacian for regular graphs, it is different for non-regular graphs and is thus an inequivalent quantum walk. We algorithmically explore this distinction by analyzing search on the complete bipartite graph with multiple marked vertices, using both the Laplacian and adjacency matrix. The two walks differ qualitatively and quantitatively in their required jumping rate, runtime, sampling of marked vertices, and in what constitutes a natural initial state. Thus the choice of the Laplacian or adjacency matrix to effect the walk has important algorithmic consequences.

  19. Emission of pesticides during drilling and deposition in adjacent areas

    Directory of Open Access Journals (Sweden)

    Heimbach, Udo

    2014-02-01

    Full Text Available In seven experiments seeds of maize, oil seed rape and barley, treated with neonicotinoids, were sown using pneumatic drilling equipment with deflectors attached in case of pneumatic suction systems. Directly adjacent to the drilled area of usually about 50 m width were replicated areas with bare soil as well as with crops. During maize (Zea mays drilling flowering oil seed rape (Brassica napus and during drilling of barley (Hordeum vulgare and oil seed rape flowering white mustard (Sinapis alba was adjacent. The amount of residues in the adjacent non crop areas in Petri dishes being distributed on the bare soil declined only slowly from 1 to 20 m distance from the area drilled. Seed batches with more abrasion and higher content of active substances in the dust resulted in higher residues off crop. After drilling of maize in four experiments in Petri dishes in adjacent non crop areas in 1-5 m distance between 0.02 and 0.40 g a.s./ha of neonicotinoids and in the adjacent oil seed rape a total of 0.05–0.80 g a.s./ha were detected. After drilling oil seed rape or barley these values were only 0.02–0.06 g a.s./ha in Petri dishes in non crop areas and 0.03-0.08 g a.s./ha in total in adjacent white mustard. In gauze net samplers installed vertically in 3 m distance in non crop areas up to seven times higher values were detected compared to Petri dishes.

  20. Crystal Data

    Science.gov (United States)

    SRD 3 NIST Crystal Data (PC database for purchase)   NIST Crystal Data contains chemical, physical, and crystallographic information useful to characterize more than 237,671 inorganic and organic crystalline materials. The data include the standard cell parameters, cell volume, space group number and symbol, calculated density, chemical formula, chemical name, and classification by chemical type.

  1. N-(4-Methyl-phenyl-sulfon-yl)succinamic acid.

    Science.gov (United States)

    Purandara, H; Foro, Sabine; Gowda, B Thimme

    2012-06-01

    In the crystal structure of the title compound, C(11)H(13)NO(5)S, the amide C=O and the carboxyl C=O groups of the acid segment orient themselves away from each other. The dihedral angle between the benzene ring and the amide group is 69.0 (2)°. In the crystal, N-H⋯O and O-H⋯O hydrogen bonds link the mol-ecules into layers parallel to the bc plane.

  2. Crystal structure of dioxidobis(pentane-2,4-dionato-κ(2) O,O')[1-phenyl-3-(pyridin-4-yl)propane-κN]uranium(VI).

    Science.gov (United States)

    Kawasaki, Takeshi; Kitazawa, Takafumi

    2015-01-01

    In the title compound, [UO2(C5H7O2)2(C14H15N)], the uran-yl(VI) unit ([O=U=O](2+)) is coordinated to two acetyl-acetonate (acac) anions and one 1-phenyl-3-(pyridin-4-yl)propane (ppp) mol-ecule. The geometry around the U atom is UNO6 penta-gonal-bipyramidal; two uran-yl(VI) O atoms are located at the axial positions, whereas four O atoms from two chelating bidentate acac ligands and one N atom of a ppp ligand form the equatorial plane.

  3. Crystal structure of bis-(9H-6-amino-purin-1-ium) hexa-fluorido-silicate(IV) dihydrate.

    Science.gov (United States)

    Belhouas, Ratiba; Bouacida, Sofiane; Boudaren, Chaouki; Daran, Jean-Claude; Chtoun, El Hossain

    2015-02-01

    The asymmetric unit of the title compound, 2C5H6N5 (+)·SiF6 (2-)·2H2O, contains one adeninium cation, half of a hexa-fluorido-silicate anion located on an inversion centre and one lattice water mol-ecule. The adeninium cations are connected through N-H⋯N hydrogen bonds involving one H atom of the -NH2 group and the H atom of the protonated N atom of the adenine ring system, forming centrosymmetric ring motifs of the type R 2 (2)(10) and R 2 (2)(8), respectively. The overall connection of the cation leads to the formation of planar ribbons parallel to (122). In the ribbons, slipped π-π stacking inter-actions, with a centroid-to-centroid distance of 3.6938 (9) Å, an inter-planar distance of 3.455 Å and a slippage of 1.306 Å is observed. The hexa-fluorido-silicate anion and the water mol-ecule are linked through O-H⋯F hydrogen bonds [ring motif R 4 (4)(12)] into chains parallel to [100]. The cationic ribbons and anionic chains are finally connected through additional N-H⋯O, N-H⋯F and O-H⋯F hydrogen bonds into a three-dimensional network in which layers of adeninium cations and fluorido-silicate anions alternate parallel to (001).

  4. Crystal structure of bis-(di-methyl-ammonium) hexa-aqua-nickel(II) bis-(sulfate) dihydrate.

    Science.gov (United States)

    Held, Peter

    2014-11-01

    In the title salt, (C2H8N)2[Ni(H2O)6)](SO4)2·2H2O, the Ni(II) cation is located on a centre of inversion and exhibits a slightly distorted octa-hedral arrangement of water mol-ecules. The Ni-O bond lengths in the complex [Ni(H2O)6](2+) cation show a distribution as in the related Tutton salt (NH4)2[Ni(H2O)6](SO4)2, but are longer in average [2.056 (13) versus 2.037 (12) Å]. The noncoordinating water mol-ecules and di-methyl-ammonium cations connect the sulfate and [Ni(H2O)6](2+) octa-hedra via O-H⋯O and N-H⋯O hydrogen bonds from weak up to medium strength into a three-dimensional framework whereby the complex metal cations and sulfate anions are arranged in sheets parallel (001).

  5. 1-Nitro-4-(4-nitro-phen-oxy)benzene: a second monoclinic polymorph.

    Science.gov (United States)

    Naz, Mehwish; Akhter, Zareen; McKee, Vickie; Nadeem, Arif

    2013-11-01

    In the title compound, C12H8N2O5, the aromatic rings are inclined to one another by 56.14 (7)°. The nitro groups are inclined by to the benzene rings to which they are attached by 3.86 (17) and 9.65 (15)°. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming a three-dimensional structure. The title compound is a new monoclinic polymorph, crystallizing in space group P21/c. The first polymorph crystallized in space group C2/c and the mol-ecule possesses twofold rotation symmetry. Two low-temperature structures of this polymorph (150 K and 100 K, respectively) have been reported [Meciarova et al. (2004). Private Communication (refcode IXOGAD). CCDC, Cambridge, England, and Dey & Desiraju (2005). Chem. Commun. pp. 2486-2488].

  6. Macromolecular crystallization and crystal perfection

    CERN Document Server

    Chayen, Naomi E; Snell, Edward H

    2010-01-01

    Structural biology is key to our understanding of the mechanisms of biological processes. This text describes current methods and future frontiers in crystal growth and use of X-ray and neutron crystallography, in the context of automation of crystallization and generation of synchrotron X-ray and neutron beams.

  7. Migration of PCBs from Sealants to Adjacent Material

    DEFF Research Database (Denmark)

    Andersen, Helle Vibeke; Gunnarsen, Lars Bo; Kampmann, Kristoffer

    2015-01-01

    adjacent to outdoor PCB-containing sealants. The samples were submitted to the laboratory for normal commercial assessment of PCB content in relation to the handling of waste from renovation works in Denmark. The results showed that the PBC concentration in the sealant not necessarily relate...

  8. Flow and edge scour in current adjacent to stone covers

    DEFF Research Database (Denmark)

    Petersen, Thor U.; Sumer, B. Mutlu; Bøgelund, Jon;

    2015-01-01

    This paper presents the results of an experimental investigation on edge scour adjacent to a stone cover laid on a sandy bed. The three-dimensional flow over the edge of the stone layer has been investigated by the use of particle image velocimetry. The flow measurements show a significant amount...

  9. Adjacent segment degeneration: observations in a goat spinal fusion study

    NARCIS (Netherlands)

    R.J.W. Hoogendoorn; M.N. Helder; P.I.J.M. Wuisman; R.A. Bank; V. Everts; T.H. Smit

    2008-01-01

    Study Design. The adjacent discs of 13 goats, originally used in a lumbar spinal fusion model study, were analyzed for symptoms of intervertebral disc degeneration by means of magnetic resonance imaging (MRI), macroscopy, and histology. These goats were followed for 6 months and the results were com

  10. Experimental Tape Casting of Adjacently Graded Materials for Magnetic Refrigeration

    DEFF Research Database (Denmark)

    Bulatova, Regina

    graded thin films. The motivation to create such adjacently segmented structures stemmed from a search of material and a materials design alternative to the expensive rare earth element gadolinium which is widely used as a magnetic regenerator in the emerging magnetic refrigeration technology...

  11. Measurement Methods to Determine Air Leakage Between Adjacent Zones

    Energy Technology Data Exchange (ETDEWEB)

    Hult, Erin L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dickerhoff, Darryl J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Phillip N. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-09-01

    Air leakage between adjacent zones of a building can lead to indoor air quality and energy efficiency concerns, however there is no existing standard for measuring inter-zonal leakage. In this study, synthesized data and field measurements are analyzed in order to explore the uncertainty associated with different methods for collecting and analyzing fan pressurization measurements to calculate interzone leakage.

  12. Liquid crystal tunable photonic crystal dye laser

    DEFF Research Database (Denmark)

    Buss, Thomas; Christiansen, Mads Brøkner; Smith, Cameron

    2010-01-01

    We present a dye-doped liquid crystal laser using a photonic crystal cavity. An applied electric field to the liquid crystal provides wavelength tunability. The photonic crystal enhances resonant interaction with the gain medium....

  13. Crystal Dislocations

    Directory of Open Access Journals (Sweden)

    Ronald W. Armstrong

    2016-01-01

    Full Text Available Crystal dislocations were invisible until the mid-20th century although their presence had been inferred; the atomic and molecular scale dimensions had prevented earlier discovery. Now they are normally known to be just about everywhere, for example, in the softest molecularly-bonded crystals as well as within the hardest covalently-bonded diamonds. The advent of advanced techniques of atomic-scale probing has facilitated modern observations of dislocations in every crystal structure-type, particularly by X-ray diffraction topography and transmission electron microscopy. The present Special Issue provides a flavor of their ubiquitous presences, their characterizations and, especially, their influence on mechanical and electrical properties.

  14. Relative substituent orientation in the structure of cis-3-chloro-1,3-dimethyl-N-(4-nitro-phen-yl)-2-oxo-cyclo-pentane-1-carboxamide.

    Science.gov (United States)

    Zeller, Matthias; Warneke, Jonas; Azov, Vladimir

    2014-09-01

    The structure of the title compound, C14H15ClN2O4, prepared by reaction of a methacryloyl dimer with nitro-aniline, was determined to establish the relative substituent orientation on the cyclo-penta-none ring. In agreement with an earlier proposed reaction mechanism, the amide group and the methyl group adjacent to the chloro substituent adopt equatorial positions and relative cis orientation, whereas the Cl substituent itself and the methyl group adjacent to the amide have axial orientations relative to the mean plane of the five-membered ring. The conformation of the mol-ecule is stabilized by one classical N-H⋯O (2.18 Å) and one non-classical C-H⋯O (2.23 Å) hydrogen bond, each possessing an S(6) graph-set motif. The crystal packing is defined by several non-classical intra-molecular hydrogen bonds, as well as by partial stacking of the aromatic rings.

  15. Improvement parameters in dynamic compaction adjacent to the slopes

    Directory of Open Access Journals (Sweden)

    Elham Ghanbari

    2015-04-01

    Full Text Available Dynamic compaction is a cost-effective method commonly used for improvement of sandy soils. A number of researchers have investigated experimentally and numerically the improvement parameters of soils using dynamic compaction, such as crater depth, improvement depth, and radial improvement, however, these parameters are not studied for improvement adjacent to the slopes or trenches. In this research, four different slopes with different inclinations are modeled numerically using the finite element code ABAQUS, and impact loads of dynamic compaction are applied. The static factors of safety are kept similar for all trenches and determined numerically by application of gravity loads to the slope using strength reduction method (SRM. The analysis focuses on crater depth and improvement region which are compared to the state of flat ground. It can be observed that compacted area adjacent to the slopes is narrower and slightly away from the slope compared to the flat state. Moreover, crater depth increases with increase in slope inclination.

  16. Resonance-like tunneling across a barrier with adjacent wells

    Indian Academy of Sciences (India)

    S Mahadevan; P Prema; S K Agarwalla; B Sahu; C S Shastry

    2006-09-01

    We examine the behavior of transmission coefficient across the rectangular barrier when attractive potential well is present on one or both sides and also the same is studied for a smoother barrier with smooth adjacent wells having Woods–Saxon shape. We find that presence of well with suitable width and depth can substantially alter at energies below the barrier height leading to resonant-like structures. In a sense, this work is complementary to the resonant tunneling of particles across two rectangular barriers, which is being studied in detail in recent years with possible applications in mind. We interpret our results as due to resonant-like positive energy states generated by the adjacent wells. We describe in detail the possible potential application of these results in electronic devices using n-type oxygen-doped gallium arsenide and silicon dioxide. It is envisaged that these results will have applications in the design of tunneling devices.

  17. Regional Fault Systems of Qaidam Basin and Adjacent Orogenic Belts

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The purpose of this paper is to analyze the regional fault systems of Qaidam basin and adjacent orogenic belts. Field investigation and seismic interpretation indicate that five regional fault systems occurred in the Qaidam and adjacent mountain belts, controlling the development and evolution of the Qaidam basin. These fault systems are: (1)north Qaidam-Qilian Mountain fault system; (2) south Qaidam-East Kunlun Mountain fault system; (3)Altun strike-slip fault system; (4)Elashan strike-slip fault system, and (5) Gansen-Xiaochaidan fault system. It is indicated that the fault systems controlled the orientation of the Qaidam basin, the formation and distribution of secondary faults within the basin,the migration of depocenters and the distribution of hydrocarbon accumulation belt.

  18. New adjacent Bis-tetrahydrofuran Annonaceous acetogenins from Annona muricata.

    Science.gov (United States)

    Chang, Fang-Rong; Liaw, Chih-Chuang; Lin, Chih-Yuan; Chou, Chi-Jung; Chiu, Hui-Fen; Wu, Yang-Chang

    2003-03-01

    Bioactivity-guided fractionation led to the isolation of two new Annonaceous acetogenins, annocatacin A ( 1). and annocatacin B ( 2). from the seeds and the leaves, respectively, of Annona muricata. Compounds 1 and 2 are the first examples where the adjacent bis-tetrahydrofuran ring system is located at C-15. The new structures were elucidated and characterized by spectral and chemical methods. Both Annonaceous acetogenins 1 and 2 showed significant in vitro cytotoxicity toward the human hepatoma cell lines, Hep G2 and 2,2,15, and were compared with the known adjacent bis-tetrahydrofuran acetogenins, neoannonin ( 3). desacetyluvaricin ( 4). bullatacin ( 5). asimicin ( 6). annoglaucin ( 7). squamocin ( 8). and rollimusin ( 9).

  19. Geodynamical features and geotectonic evolution of Kalimantan and adjacent areas

    Institute of Scientific and Technical Information of China (English)

    杨牧; 彭省临

    2004-01-01

    Kalimantan Island is located in the Southeast Asia continental marginal tectono-magmatic mobile zone in the West Pacific Ocean, where the lithosphere of Earth is one of the most complicated tectonic mobile regions on the Earth since Meso-Cenozoic. Based on the geophysical data of the basement and deep structures, the stress field of mantle flow, the maximum principal stress field and geothermal flux, the crustal nature and geodynamical features of Kalimantan Island and adjacent areas were analyzed. Researches on geotectonic movement and evolution of Kalimantan and adjacent areas show that Southeast Asia continental margin crustobody was formed at about middle-late Triassic. In addition, the geotectonic units of the Kalimantan area were subdivided, and characteristics of their geotectonic evolution were discussed.

  20. Improvement parameters in dynamic compaction adjacent to the slopes

    Institute of Scientific and Technical Information of China (English)

    Elham Ghanbari; Amir Hamidi

    2015-01-01

    Dynamic compaction is a cost-effective method commonly used for improvement of sandy soils. A number of researchers have investigated experimentally and numerically the improvement parameters of soils using dynamic compaction, such as crater depth, improvement depth, and radial improvement, however, these parameters are not studied for improvement adjacent to the slopes or trenches. In this research, four different slopes with different inclinations are modeled numerically using the finite element code ABAQUS, and impact loads of dynamic compaction are applied. The static factors of safety are kept similar for all trenches and determined numerically by application of gravity loads to the slope using strength reduction method (SRM). The analysis focuses on crater depth and improvement region which are compared to the state of flat ground. It can be observed that compacted area adjacent to the slopes is narrower and slightly away from the slope compared to the flat state. Moreover, crater depth increases with increase in slope inclination.

  1. Adjacent segment disease in degenerative pathologies with posterior instrumentation

    OpenAIRE

    Ana Guadalupe Ramírez Olvera; Manuel Villarreal Arroyo; Luis Mario Hinojosa Martínez; Enrique Méndez Pérez; Luis Romeo Ramos Hinojosa

    2015-01-01

    OBJECTIVE: To establish the real incidence of adjacent segment disease after fusion, and to identify the levels and predisposing factors for the pathology, as well as the functional results. METHODS: a retrospective case series study with level of evidence IIB, in a sample of 179 patients diagnosed with stenosis of the lumbar spine, spondylolisthesis and degenerative scoliosis, submitted to surgery in the period 2005 to December 2013, with posterior instrumentation and posterolateral fusion, ...

  2. Acyclic Edge Coloring of Planar Graphs without Adjacent Triangles

    Institute of Scientific and Technical Information of China (English)

    Dezheng XIE; Yanqing WU

    2012-01-01

    An acyclic edge coloring of a graph G is a proper edge coloring such that there are no bichromatic cycles.The acyclic edge chromatic number of a graph G is the minimum number k such that there exists an acyclic edge coloring using k colors and is denoted by x'a(G).In this paper we prove that x'a(G)≤ Δ(G)+ 5 for planar graphs G without adjacent triangles.

  3. Processing multiple non-adjacent dependencies: evidence from sequence learning.

    Science.gov (United States)

    de Vries, Meinou H; Petersson, Karl Magnus; Geukes, Sebastian; Zwitserlood, Pienie; Christiansen, Morten H

    2012-07-19

    Processing non-adjacent dependencies is considered to be one of the hallmarks of human language. Assuming that sequence-learning tasks provide a useful way to tap natural-language-processing mechanisms, we cross-modally combined serial reaction time and artificial-grammar learning paradigms to investigate the processing of multiple nested (A(1)A(2)A(3)B(3)B(2)B(1)) and crossed dependencies (A(1)A(2)A(3)B(1)B(2)B(3)), containing either three or two dependencies. Both reaction times and prediction errors highlighted problems with processing the middle dependency in nested structures (A(1)A(2)A(3)B(3)_B(1)), reminiscent of the 'missing-verb effect' observed in English and French, but not with crossed structures (A(1)A(2)A(3)B(1)_B(3)). Prior linguistic experience did not play a major role: native speakers of German and Dutch-which permit nested and crossed dependencies, respectively-showed a similar pattern of results for sequences with three dependencies. As for sequences with two dependencies, reaction times and prediction errors were similar for both nested and crossed dependencies. The results suggest that constraints on the processing of multiple non-adjacent dependencies are determined by the specific ordering of the non-adjacent dependencies (i.e. nested or crossed), as well as the number of non-adjacent dependencies to be resolved (i.e. two or three). Furthermore, these constraints may not be specific to language but instead derive from limitations on structured sequence learning.

  4. Predicting Agenesis of the Mandibular Second Premolar from Adjacent Teeth.

    Directory of Open Access Journals (Sweden)

    Geetanjali Sharma

    Full Text Available Early diagnosis of agenesis of the mandibular second premolar (P2 enhances management of the dental arch in the growing child. The aim of this study was to explore the relationship in the development of the mandibular first molar (M1 and first premolar (P1 at early stages of P2 (second premolar. Specifically, we ask if the likelihood of P2 agenesis can be predicted from adjacent developing teeth. We selected archived dental panoramic radiographs with P2 at crown formation stages (N = 212 and calculated the likelihood of P2 at initial mineralisation stage 'Ci' given the tooth stage of adjacent teeth. Our results show that the probability of observing mandibular P2 at initial mineralisation stage 'Ci' decreased as both the adjacent P1 and M1 matured. The modal stage at P2 'Ci' was P1 'Coc' (cusp outline complete and M1 'Crc' (crown complete. Initial mineralisation of P2 was observed up to P1 'Crc' and M1 stage 'R½' (root half. The chance of observing P2 at least 'Coc' (coalescence of cusps was considerably greater prior to these threshold stages compared to later stages of P1 and M1. These findings suggest that P2 is highly unlikely to develop if P1 is beyond 'Crc' and M1 is beyond 'R½'.

  5. Heat flow distribution in Chinese continent and its adjacent areas

    Institute of Scientific and Technical Information of China (English)

    Wei Tao; Zhengkang Shen

    2008-01-01

    Using a compilation of 6980 heat flow measurements, we produce a new heat flow map for the Chinese continent and its adjacent areas. We develop an objective and integrated method to interpolate the heat flow data, taking into account both the uniformity within geological units and coherency of regional heat flow. The geologic units are outlined based on Zhang et al.'s active tectonic block model.Our heat flow model is presented in two formats: a contour map and a heat flow dataset with values on a 1 × 1° grid for the Chinese continent and its adjacent areas, reflecting detailed variations in some regions. Also provided is a resolution map which helps understand the reliability of the heat flow model. Our results reveal that (1) Heat flows in the eastern part of the Chinese continent are relatively higher than those in the western part except that in the Tibetan Plateau area. (2) Heat flows in the Ordos and North China blocks are around 60 mW/m2, and are 50-55 mW/m2 in South China except for the continental marginal sea regions. (3) Heat flow is the lowest in the Jtmggar Basin, only 35-45 mW/m2, and is 45-55 mW/m2 in the Tarim Basin. The results of this study provide an important data-set for studies on thermal and rheological structures of the Chinese continent and its adjacent areas.

  6. OVERLOAD STUDY ON ADJACENT DISC AFTER ARTHRODESIS IN THORACOLUMBAR FRACTURES

    Directory of Open Access Journals (Sweden)

    GUSTAVO SERRA REINAS

    Full Text Available ABSTRACT Objective: To analyze the degeneration of the adjacent disc after arthrodesis due to thoracolumbar fractures. Methods: Eighty-three patients who underwent posterolateral arthrodesis in thoracolumbar levels had their x-rays analyzed for degeneration of adjacent discs to the arthrodesis. The disc spaces were classified by the UCLA scale. Results: Of the 83 patients evaluated, 66 were males (79% and 18 females (21%, with a mean age of 35.5 years. The mean follow-up period was 40 months. As the fractures 75% were between T12 and L2 (p<0.001, being of the A3 type in 65% of the cases (p<0.001. The most common mechanism of injury, accounting for 50% of the cases (p<0.001, was fall from height. Only 6% of the superior discs and 12% of the inferior ones showed some degree of degeneration. No patient underwent a new surgical approach. Conclusion: The incidence of degeneration on adjacent disc in patients after arthrodesis resulting from fractures ranged from 6% to 12% with an average follow-up of 40 months.

  7. Tris[2-(2H-indazol-2-yl)eth-yl]amine.

    Science.gov (United States)

    Ovalle, Saúl; Elizondo Martínez, Perla; Pérez Rodríguez, Nancy; Bernès, Sylvain; Flores-Alamo, Marcos

    2012-06-01

    The title tertiary amine, C(27)H(27)N(7), a potential tripodal ligand for coordination chemistry, crystallizes with the central N atom located on a threefold axis of a trigonal cell. The gauche conformation of the N(amime)-CH(2)-CH(2)-N(indazole) chain [torsion angle = -64.2 (2)°] places the pendant 2H-indazole heterocycles surrounding the symmetry axis, affording a claw-like shaped mol-ecule. Two symmetry-related indazole planes in the mol-ecule make an acute angle of 60.39 (4)°. The lone pair of the tertiary N atom is located inside the cavity, and should thus be inactive (as a ligand). In the crystal, neither significant π-π nor C-H⋯π inter-actions between molecules are found.

  8. Liquid Crystals

    Science.gov (United States)

    1990-01-01

    Thermochromic liquid crystals, or TLCs, are a type of liquid crystals that react to changes in temperature by changing color. The Hallcrest/NASA collaboration involved development of a new way to visualize boundary layer transition in flight and in wind tunnel testing of aircraft wing and body surfaces. TLCs offered a new and potentially better method of visualizing the boundary layer transition in flight. Hallcrest provided a liquid crystal formulation technique that afforded great control over the sensitivity of the liquid crystals to varying conditions. Method is of great use to industry, government and universities for aerodynamic and hydrodynamic testing. Company's principal line is temperature indicating devices for industrial use, such as non-destructive testing and flaw detection in electric/electronic systems, medical application, such as diagnostic systems, for retail sale, such as room, refrigerator, baby bath and aquarium thermometers, and for advertising and promotion specials. Additionally, Hallcrest manufactures TLC mixtures for cosmetic applications, and liquid crystal battery tester for Duracell batteries.

  9. Photonic crystals

    CERN Document Server

    Busch, Kurt; Wehrspohn, Ralf B; Föll, Helmut

    2006-01-01

    The majority of the contributions in this topically edited book stems from the priority program SPP 1113 ""Photonische Kristalle"" run by the Deutsche Forschungsgemeinschaft (DFG), resulting in a survey of the current state of photonic crystal research in Germany. The first part of the book describes methods for the theoretical analysis of their optical properties as well as the results. The main part is dedicated to the fabrication, characterization and modeling of two- and three-dimensional photonic crystals, while the final section presents a wide spectrum of applications: gas sensors, micr

  10. 3,4-Dimeth-oxy-N-((E)-4-{[1-(prop-2-en-1-yl)-1H-1,2,3-triazol-4-yl]meth-oxy}benzyl-idene)aniline.

    Science.gov (United States)

    Akkurt, Mehmet; Jarrahpour, Aliasghar; Sharghi, Hashem; Chermahini, Mehdi Mohammadi; Shiri, Pezhman; Büyükgüngör, Orhan

    2012-07-01

    In the title compound, C(21)H(22)N(4)O(3), the triazole ring is planar [maximum deviaton = 0.004 (1) Å] and makes dihedral angles of 26.21 (8) and 38.66 (8)° with the two benzene rings. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming zigzag chains along [1-11]. In addition, a weak C-H⋯π intreraction is also observed.

  11. Tetra-kis(1H-imidazole-κN)(2-phenyl-propanedioato-κO,O)nickel(II).

    Science.gov (United States)

    Zhang, Kou-Lin; Diao, Guo-Wang; Ng, Seik Weng

    2010-10-23

    In the title complex, [Ni(C(9)H(6)O(4))(C(3)H(4)N(2))(4)], the Ni(II) ion is O,O'-chelated by the phenyl-malonato ligand and coordinated by four imidazole ligands in a slightly distorted octa-hedral geometry. In the crystal structure, symmetry-related mol-ecules are linked by N-H⋯O hydrogen bonds, generating a three-dimensional network.

  12. Ethyl 3-(4-hydroxy-phen-oxy)-2-(4-methoxy-phen-yl)acrylate.

    Science.gov (United States)

    Hou, Jin

    2008-11-08

    In the title compound, C(18)H(18)O(5), the dihedral angle between the two benzene rings is 55.2 (3)°. The ethyl acrylate linkage is planar and forms dihedral angles of 21.3 (3) and 41.0 (3)°, respectively, with the hydroxy-phenyl and methoxy-phenyl rings. In the crystal structure, mol-ecules are linked into zigzag chains along the b axis by O-H⋯O hydrogen bonds.

  13. 4-Hy-droxy-1-methyl-3-phenyl-quinolin-2(1H)-one.

    Science.gov (United States)

    Kafka, Stanislav; Pevec, Andrej; Proisl, Karel; Kimmel, Roman; Košmrlj, Janez

    2013-02-01

    In the title compound, C(16)H(13)NO(2), the quinoline system is approximately planar with a maximum deviation from the least-squares plane of 0.059 (1) Å for the N atom. The phenyl ring is rotated by 62.16 (4)° with respect to the plane of the quinoline system. In the crystal, O-H⋯O hydrogen bonds link mol-ecules into infinite chains running along the b-axis direction.

  14. Di-aqua-tetra-kis-(1H-imidazole-κN (3))magnesium dichloride.

    Science.gov (United States)

    Kayalvizhi, M; Vasuki, G; Kaabi, Kamel; Ben Nasr, Cherif

    2013-01-01

    In the title compound, [Mg(C3H3N2)4(H2O)2]Cl2, the Mg(II) cation lies on a crystallographic inversion centre and is coordinated by two water mol-ecules and four N-atom donors from monodentate imidazole ligands, giving a slightly distorted octa-hedral stereochemistry. In the crystal, water O-H⋯Cl and imidazole N-H⋯Cl hydrogen bonds give rise to a three-dimensional structure.

  15. N-(3-Chloro-2-methyl-phen-yl)succinamic acid.

    Science.gov (United States)

    Gowda, B Thimme; Foro, Sabine; Chaithanya, U

    2012-06-01

    In the title compound, C(11)H(12)ClNO(3), the dihedral angle between the benzene ring and the amide group is 44.9 (2)°. In the crystal, mol-ecules form inversion dimers via pairs of O-H⋯O hydrogen bonds. These dimers are further linked into sheets parallel to (013) via N-H⋯O hydrogen bonds.

  16. 3-Acetyl-1-(2,5-dimethyl-phen-yl)thio-urea.

    Science.gov (United States)

    Gowda, B Thimme; Foro, Sabine; Kumar, Sharatha

    2012-08-01

    In the title compound, C(11)H(14)N(2)OS, the thioamide C=S and amide C=O bonds are anti to each other; the N-H bonds are also anti to each other. The mol-ecular conformation is stabilized by an N-H⋯O hydrogen bond. In the crystal, the mol-ecules are linked into inversion dimers by pairs of N-H⋯S hydrogen bonds.

  17. 4-Chloro-N-(2,3-dichloro-phen-yl)-2-methyl-benzene-sulfonamide.

    Science.gov (United States)

    Rodrigues, Vinola Z; Foro, Sabine; Gowda, B Thimme; Shakuntala, K

    2011-11-01

    The torsion angle of the C-SO(2)-NH-C moiety in the title compound, C(13)H(10)Cl(3)NO(2)S, is 50.4 (2)°. The sulfonyl and aniline benzene rings are tilted relative to each other by 69.6 (1)°. The crystal structure is stabilized by N-H⋯O hydrogen bonds, linking the mol-ecules into zigzag chains parallel to the b axis.

  18. N-(4-Chloro-3-nitro-phen-yl)succinamic acid.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-04-01

    In the title compound, C(10)H(9)ClN(2)O(5), the nitro group is significantly twisted out of the plane of the benzene ring to which it is attached [dihedral angle = 27.4 (6)°]. In the crystal, mol-ecules are linked into centrosymmetric dimers via pairs of O-H⋯O hydrogen bonds. These dimers are further linked by N-H⋯O hydrogen bonds into double chains running along the a axis.

  19. 4-Chloro-N-(3,5-dichloro-phen-yl)-2-methyl-benzene-sulfonamide.

    Science.gov (United States)

    Rodrigues, Vinola Z; Foro, Sabine; Gowda, B Thimme; Shakuntala, K

    2011-11-01

    In the title compound, C(13)H(10)Cl(3)NO(2)S, torsion angle of the C-SO(2)-NH-C group in the mol-ecule is -58.57 (26)°. The sulfonyl and aniline benzene rings are tilted relative to each other by 84.2 (1)°. The crystal structure features inversion-related dimers linked by pairs of N-H⋯O hydrogen bonds.

  20. Diaqua-bis[2,5-dichloro-N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)benzene-sulfonamidato-κN]zinc(II).

    Science.gov (United States)

    da Silva, Luiz Everson; de Sousa, Paulo Teixeira; Dall'oglio, Evandro Luiz; Foro, Sabine

    2007-12-06

    In the title compound, [Zn(C(17)H(14)Cl(2)N(3)O(3)S)(2)(H(2)O)(2)], the Zn(II) ion has a tetra-hedral coordination formed by the two N atoms of the sulfonamide groups and the two water mol-ecules. Two inter- and two intra-molecular O-H⋯O hydrogen bonds are observed in the crystal structure.

  1. N-(2-Methyl-phen-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-09-01

    In the title compound, C(13)H(12)N(2)O(4)S, the dihedral angle between the benzene rings is 53.44 (14)°. The amide H atom exhibits bifurcated hydrogen bonding: an intra-molecular N-H⋯O hydrogen bond generates an S(7) motif while in the crystal, N-H⋯O(S) hydrogen bonds link the mol-ecules into zigzag C(4) chains along the c axis.

  2. N-(3-Methyl-phen-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-09-01

    In the title compound, C(13)H(12)N(2)O(4)S, the dihedral angle between the benzene rings is 73.64 (7)°. The amide H atom exhibits bifurcated hydrogen bonding: an intra-molecular N-H⋯O hydrogen bond generates an S(7) motif while in the crystal, N-H⋯O(S) hydrogen bonds link the mol-ecules into zigzag C(4) chains running along the b axis.

  3. Ribbon Crystals

    DEFF Research Database (Denmark)

    Bohr, Jakob; Markvorsen, Steen

    2013-01-01

    A repetitive crystal-like pattern is spontaneously formed upon the twisting of straight ribbons. The pattern is akin to a tessellation with isosceles triangles, and it can easily be demonstrated with ribbons cut from an overhead transparency. We give a general description of developable ribbons...

  4. Therapeutic Crystals

    Science.gov (United States)

    Bond, Charles S.

    2014-01-01

    Some readers might not fully know what the difference is between crystallography, and the "new age" practice of dangling crystals around the body to capitalise on their healing energy. The latter is often considered to be superstition, while ironically, the former has actually resulted in real rationally-based healing of human diseases…

  5. An ElGamal Encryption Scheme of Adjacency Matrix and

    Directory of Open Access Journals (Sweden)

    B. Ravi Kumar

    2015-10-01

    Full Text Available  Cryptography is the combination of Mathematics and Computer science. Cryptography is used for encryption and decryption of data using mathematics. Cryptography transit the information in an illegible manner such that only intended recipient will be able to decrypt the information. In the recent years, researchers developed several new encryption methods. Among such ElGamal encryption is the one laid a concede platform for the researchers in Cryptography. Ever science several mathematical models were applied for encryption/decryption. In this paper, we introduced an ElGamal encryption, which uses points on the elliptic curve, and finite state machines and adjacency matrix.

  6. Historical Earthquakes in the Yellow Sea and Its Adjacent Area

    Institute of Scientific and Technical Information of China (English)

    Wu Ge; Wang Andong; Wu Di

    2005-01-01

    As a result of sorting out, estimating and cataloging of historical earthquakes, from the year of 2 A.D. to Aug., 1949, we found that there were 2187 earthquakes with M≥3.0 in the area of the Yellow Sea and its adjacent area. Among the earthquakes, the number of earthquakes with M ≥ 5.0 is 209, and at least 43 of the earthquakes caused serious losses, 20 of the earthquakes caused human causalities. It is demonstrated that there were 3 areas of historical earthquake concentration and the earthquake activity was higher in the 16th century and the first half if the 20th century.

  7. Osteoid Osteoma of Cervical Spine in two adjacent Vertebrae

    Directory of Open Access Journals (Sweden)

    MR Etemadifar

    2005-09-01

    Full Text Available Osteoid osteoma is a benign bone tumor, mainly seen in 10-30 years male. Spine is a relatively common site and almost always, posterior elements are involved. Plain X-Ray-, CT scan and Isotope scan help to identify and localize spine lesions. We described one 18 years old boy with 3 years low neck pain. Isotope scan, MRI and CT scan showed two lesions in C7 and T1. Gross inspection and histopathology examination confirmed osteoid osteoma in two adjacent vertebrae which has not been reported elsewhere in the literature. Key words: Osteoid Osteoma, Spine, Multifocal

  8. Photonic crystals principles and applications

    CERN Document Server

    Gong, Qihuang

    2013-01-01

    IntroductionPrimary Properties of Photonic CrystalsFabrication of Photonic CrystalsPhotonic Crystal All-Optical SwitchingTunable Photonic Crystal FilterPhotonic Crystal LaserPhotonic Crystal Logic DevicesPhotonic Crystal Sensors

  9. Adjacent segment disease in degenerative pathologies with posterior instrumentation

    Directory of Open Access Journals (Sweden)

    Ana Guadalupe Ramírez Olvera

    2015-03-01

    Full Text Available OBJECTIVE: To establish the real incidence of adjacent segment disease after fusion, and to identify the levels and predisposing factors for the pathology, as well as the functional results. METHODS: a retrospective case series study with level of evidence IIB, in a sample of 179 patients diagnosed with stenosis of the lumbar spine, spondylolisthesis and degenerative scoliosis, submitted to surgery in the period 2005 to December 2013, with posterior instrumentation and posterolateral fusion, with follow-up from 2007 until May 2014, in which the symptomology and radiographic findings were evaluated, to establish the diagnosis and treatment. RESULTS: the study included 179 patients diagnosed with stenosis of the lumbar spine (n=116, isthmic and degenerative spondylolisthesis (n=50 and degenerative scoliosis (n=13; during the study, 20 cases of adjacent level segment were identified, 80% of which were treated surgically with extension of the instrumentation, while 20% were treated conservatively with NSAIDs and therapeutic blocks. CONCLUSION: An incidence of 11% was found, with an average of 3.25 years in diagnosis and treatment, a prevalence of females and diagnosis of stenosis of the lumbar canal on posterior instrumentation, a predominance of levels L4-L5; 80% were treated with extension of the instrumentation. The complications were persistent radiculopathy, infection of the surgical wound, and one death due to causes not related to the lumbar pathology.

  10. Seismic anisotropy of upper mantle in Sichuan and adjacent regions

    Institute of Scientific and Technical Information of China (English)

    CHANG LiJun; WANG ChunYong; DING ZhiFeng

    2008-01-01

    Based on the polarization analysis of teleseismic SKS waveform data recorded at 94 broadband seismic stations in Sichuan and adjacent regions, the SKS fast-wave direction and the delay time between the fast and slow shear waves were determined at each station using the grid searching method of minimum transverse energy and the stacking analysis method, and the image of upper mantle anisotropy was acquired. The fast-wave polarization directions are mainly NW-SE in the study area,NWW-SEE to its northeast and NS to its west. The delay time falls into the interval [0.47 s, 1.68 s]. The spatial variation of the fast-wave directions is similar to the variation of GPS velocity directions. The anisotropic image indicates that the regional tectonic stress field has resulted in deformation and flow of upper mantle material, and made the alignment of upper mantle peridotite lattice parallel to the direction of material deformation. The crust-upper mantle deformation in Sichuan and adjacent regions accords with the mode of vertically coherent deformation. In the eastern Tibetan Plateau, the crustal material was extruded to east or southeast clue to SE traction force of the upper mantle material. The extrusion might be obstructed by a rigid block under the Sichuan Basin and the crust has been deformed. After a long-term accumulation of tectonic strain energy, the accumulative energy suddenly released in Yingxiu town of the Longmenshan region, and Wenchuan Ms8.0 earthquake occurred.

  11. Adjacent stage impurity ratio in rare earth countercurrent extraction process

    Institute of Scientific and Technical Information of China (English)

    CHENG Fuxiang; WU Sheng; LIAO Chunsheng; YAN Chunhua

    2013-01-01

    Impurity components decrease stage by stage in a cascade of rare earth (RE) extraction separation,and adjacent stage impurity ratio (ASIR) which is defined as the ratio of an impurity's contents in the aqueous/organic phase of two adjacent stages can be used to evaluate the capacity of impurity removal for the two stages.On the basis of extraction equilibrium and mass balance,the ASIR in a two-component extraction separation was deducted and its simplified expressions were given for different process sections according to reasonable assumptions.The calculation simulation was then carried out to obtain the ASIR distribution in the cascade.The results showed that in both the extraction and scrubbing sections the ASIR principally increased with the decrease of the molar proportion of the impurity but along with a flat appearing in the purification zone located in the middle of the cascade.The ASIR intuitively exhibits the nmning status of RE extraction separation and purification,which could provide a theoretic guide for investigating the influence factors of RE extraction separation process in practical industry.

  12. (SP-4-4)-[Hydrogen N-({2-[(2S)-1-benzyl-pyrrolidine-2-carboxamido]phen-yl}(phen-yl)methyl-ene)-l-glutamato(2-)]nickel(II).

    Science.gov (United States)

    Zhou, Jia-Dong; Cao, Fei; Ying, Han-Jie; Wei, Ping

    2009-03-28

    In the mol-ecule of the title complex, [Ni(C(30)H(29)N(3)O(5))], the Ni atom is coordinated in a distorted square-planar geometry by three N and one O atoms. The aromatic rings are oriented at dihedral angles of 29.01 (3), 79.73 (3) and 83.37 (3)°. The remaining rings adopt envelope conformations with the C and N atoms at the flap positions. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into chains along the b axis. There is also a weak C-H⋯π inter-action.

  13. Methyl 2-(3a,8a-dimethyl-4-oxodeca-hydro-azulen-6-yl)acrylate.

    Science.gov (United States)

    Tebbaa, Mohamed; Benharref, Ahmed; Berraho, Moha; Daran, Jean Claude; Akssira, Mohamed; Elhakmaoui, Ahmed

    2011-08-01

    The title compound, C(16)H(24)O(3), was synthesized from ilicic acid, which was isolated from the aerial part of Inula viscosa- (L) Aiton [or Dittrichia viscosa- (L) Greuter]. The asymmetric unit contains two independent mol-ecules, in each of which the seven-membered ring shows a chair conformation, whereas the five-membered ring presents disorder. In the two molecules, three C atoms in the five-membered ring are disordered over two positions with site-occupancy factors of 0.53/0.47 and 0.83/0.17. The dihedral angle between the two rings is different in the two mol-ecules [31.7 (3) and 47.7 (7)°]. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen-bond inter-actions.

  14. α-Costic anhydride.

    Science.gov (United States)

    Tebbaa, Mohamed; Akssira, Mohamed; Elhakmaoui, Ahmed; El Ammari, Lahcen; Benharref, Ahmed; Berraho, Moha

    2010-02-13

    THE TITLE COMPOUND [SYSTEMATIC NAME: 2-(4a,8-dimethyl-1,2,3,4,4a,5,6,8a-octa-hydro-naphthalen-2-yl)acrylic acid anhydride], C(30)H(42)O(3), is a new isocostic anhydride which was synthesized from the aerial part of Inula Viscosa- (L) Aiton [or Dittrichia Viscosa- (L) Greuter]. The mol-ecule adopts an essentially linear shape with two terminal fused-rings bridged by the anhydride group. The external rings have the same conformation (half-chair) while each of the two inner rings has an almost ideal chair conformation. In the crystal, inter-molecular C-H⋯O inter-actions link the mol-ecules into a two-dimensional array in the bc plane.

  15. [Malonato(2-)-κO,O']bis-(1,10-phenanthroline-κN,N')zinc(II) penta-hydrate.

    Science.gov (United States)

    Chen, Yan-Min; Xie, Qing-Fan

    2010-12-11

    In the title complex, [Zn(C(3)H(2)O(4))(C(12)H(8)N(2))(2)]·5H(2)O, the Zn(II) cation displays a distorted octa-hedral geometry, being coordinated by four N atoms from two 1,10-phenanthroline ligands and two O atoms from different carboxyl-ate groups of the chelating malonate dianion. In the crystal, the complexes are linked into a three-dimensional supra-molecular network by both O-H⋯O hydrogen-bonding inter-actions between water mol-ecules and the uncoordinated carboxyl-ate O atoms of neighboring mol-ecules, and aromatic π-π stacking inter-actions between neighboring phenanthroline rings with centroid-centroid distances of 3.4654 (17) and 3.697 (2) Å.

  16. 2-(1H-Indol-3-yl)acetohydrazide.

    Science.gov (United States)

    Sidra, Lala Rukh; Khan, Islam Ullah; Yar, Muhammad; Simpson, Jim

    2012-11-01

    In the title compound C(10)H(11)N(3)O, the mean plane of the indole ring system (r.m.s. deviation 0.0131 Å) subtends a dihedral angle of 87.27 (5)° to the almost planar acetohydrazide substituent (r.m.s. deviation 0.0291 Å). In the crystal, bifurcated N-H⋯(O,N) and N-H⋯N hydrogen bonds involving the pyrrole N-H grouping combine to form zigzag chains along a. Additional N-H⋯O contacts from the hydrazide N-H group augmented by C-H⋯π inter-actions link the mol-ecules into chains along the a axis. The overall effect of these contacts is a three-dimensional network structure with mol-ecules stacked along the b-axis direction.

  17. Tris(4-methyl-phen-yl)phosphine selenide.

    Science.gov (United States)

    Muller, Alfred

    2010-12-08

    In the title mol-ecule, C(21)H(21)PSe or PSe(C(7)H(7))(3), the P atom has a distorted PSeC(3) tetra-hedral environment, formed by the Se atom [P=Se = 2.1119 (5) Å] and three aryl rings. Two short intra-molecular C-H⋯Se contacts occur. In the crystal, weak inter-molecular C-H⋯Se inter-actions link the mol-ecules into zigzag double chains propagating in [100]. The previous report of this structure [Zhdanov et al. (1953 ▶). Dokl. Akad. Nauk SSSR (Russ.) (Proc. Nat. Acad. Sci. USSR), 92, 983-985] contained no geometrical data.

  18. N-[(9H-Fluoren-9-yl-idene)(2-meth-oxy-phen-yl)meth-yl]-1,1,1-tri-methyl-silanamine.

    Science.gov (United States)

    Li, Zhong-Yuan; Wang, Peng; Chen, Xia

    2014-01-01

    The title mol-ecule, C24H25NOSi, is a hydrolysis product of the reaction between 9-tri-methyl-silyfluorenyl lithium and 2-meth-oxy-benzo-nitrile. The fluorene ring system is substanti-ally planar, with an r.m.s. deviation of 0.0288 Å from the best-fit plane through its 13 C atoms. This plane forms a dihedral angle of 58.07 (7)° with the 2-meth-oxy-benzyl-amine ring plane. In the crystal, mol-ecules are linked by N-H⋯π and C-H⋯π inter-actions, which leads to the formation of two-dimensional network lying parallel to the bc plane.

  19. trans-Diamminedichloridobis(1H-imidazole-κN (3))nickel(II).

    Science.gov (United States)

    Kannan, Piskala Subburaman; Ganeshraja, Ayyakannu Sundaram; Rajkumar, Kanniah; Anbalagan, Krishnamoorthy; Subbiahpandi, Arunachalatheva

    2013-01-01

    The whole mol-ecule of the title compound, [NiCl2(C3H4N2)2(NH3)2], is generated by inversion symmetry. The Ni(II) ion, which is located on an inversion center, has a distorted octa-hedral coordination environment and is surrounded by two ammine N atoms and two Cl atoms in the equatorial plane, with two N atoms of two imidazole groups occupying the axial positions. The imidazole ring makes a dihedral angle of 81.78 (18)° with the Ni/N/Cl equatorial plane. In the crystal, mol-ecules are linked via N-H⋯Cl hydrogen bonds and C-H⋯π inter-actions, forming a three-dimensional network.

  20. 3-Ethyl-3-hy-droxy-8-meth-oxy-quinoline-2,4(1H,3H)-dione monohydrate.

    Science.gov (United States)

    Kafka, Stanislav; Pevec, Andrej; Proisl, Karel; Kimmel, Roman; Košmrlj, Janez

    2012-11-01

    In the title hydrate, C(12)H(13)NO(4)·H(2)O, the piperidine ring that is fused to the benzene ring is in a sofa conformation with the chiral C atom lying 0.4084 (18) Å out of the plane of the nine fused-ring atoms. In the crystal, O-H⋯O and N-H⋯O hydrogen bonds link the organic mol-ecules and water mol-ecules into chains running along the b-axis direction. The chains are further connected into layers parallel to the bc plane by π-π inter-actions between inversion-related benzene rings [centroid-centroid distance = 3.8846 (9) Å].

  1. 4,4'-Bipyridine-2-(carb-oxy-methyl-sulfan-yl)pyridine-3-carb-oxy-lic acid (1/1).

    Science.gov (United States)

    Jiang, Xian-Rong; Wang, Xiao-Juan; Feng, Yun-Long

    2010-11-27

    In the title co-crystal, C(10)H(8)N(2)·C(8)H(7)NO(4)S, the formate group is coplanar with the pyridyl ring of the acid [dihedral angle = 6.2 (7)°], while the carb-oxy-methyl-sulfanyl group makes a C-S-C-C torsion angle of 70.2 (1)° with the pyridine ring. The dihedral angle between the pyridyl rings of the 4,4'-bipyridine mol-ecule is 27.4 (1)°. The acid and the 4,4'-bipyridine mol-ecules are involved in hydrogen bonding via carb-oxy-lic O and pyridyl N atoms. The structure is further consolidated by inter-molecular C-H⋯O hydrogen bonds, generating a three-dimensional network.

  2. μ-1,4-Bis(pyridin-4-ylmeth-yl)piperazine-κN:N'-bis-[aqua-bis-(3-bromo-5-carb-oxy-benzoato-κO)copper(II)].

    Science.gov (United States)

    Meyer, Jodi L; Laduca, Robert L

    2012-02-01

    In the title compound, [Cu(2)(C(8)H(4)BrO(4))(4)(C(16)H(20)N(4))(H(2)O)(2)], slightly distorted square-planar-coordinated Cu(II) ions are bound by one aqua ligand and two monodentate 3-bromo-5-carb-oxy-benzoate anions, and linked into a centrosymmetric dinuclear mol-ecule by a bridging 1,4-bis-(pyridin-4-ylmeth-yl)piperazine (4-bpmp) ligand. In the crystal, mol-ecules are connected into a supra-molecular two-dimensional network parallel to (131) via O-H⋯O hydrogen bonds involving the aqua ligands and 3-bromo-5-carb-oxy-benzoate carboxyl-ate groups.

  3. 1-[(1S,6R,7S,9R)-8,8-Di-bromo-5,5,9-tri-methyl-tri-cyclo-[4.4.0.1(7,9)]decan-1-yl]ethanone.

    Science.gov (United States)

    Zaki, Mohamed; Benharref, Ahmed; El Ammari, Lahcen; Saadi, Mohamed; Berraho, Moha

    2014-04-01

    The title compound, C16H24Br2O, was synthesized by three steps from β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzo-cyclo-heptene), which was isolated from essential oil of the Atlas cedar cedrus atlantica. The asymmetric unit contains two independent mol-ecules with almost identical conformations. Each mol-ecule is built up from two fused six-membered rings, one having a chair conformation and the other a boat conformation, and an additional three-membered ring arising from the reaction of himachalene with di-bromo-carbene. In the crystal, there are no significant intermolecular interactions present. The absolute structure of the title compound was confirmed by resonance scattering.

  4. (1S,3S,8R,10R,11R)-3,7,7,10-Tetra-methyl-tri-cyclo-[6.4.0.0(1,3)]dodecan-11-ol.

    Science.gov (United States)

    Benharref, Ahmed; El Karroumi, Jamal; El Ammari, Lahcen; Saadi, Mohamed; Berraho, Moha

    2013-01-01

    The title compound, C16H28O, was synthesized by three steps from β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzo-cyclo-heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus atlantica). The mol-ecule is built up from fused six- and seven-membered rings and an appended three-membered ring. The six-membered ring has twist-boat conformation, whereas the seven-membered ring displays a chair conformation. In the crystal, mol-ecules are linked into chains propagating along the a-axis direction by O-H⋯O hydrogen bonds.

  5. 1-Isopropyl-4,7-dimethyl-2,8-dinitro-naphthalene.

    Science.gov (United States)

    Chakkar, Mouna; Oughris, Najia; Benharref, Ahmed; Daran, Jean-Claude; Berraho, Moha

    2012-06-01

    The title compound, C(15)H(16)N(2)O(4), was synthesized from a mixture of α-himachalene (2-methyl-ene-6,6,9-trimethyl-bicyclo-[5.4.O(1,7)]undec-8-ene) and β-himachalene (2,6,6,9-tetra-methyl-bicyclo-[5.4.0(1,7)]undeca-1,8-diene) which were isolated from an oil of the Atlas cedar (Cedrus atlantica). The asymmetric unit contains two independent mol-ecules. In each of the two mol-ecules, two O atoms of one nitro group are disordered over two sets of sites with site-occupancy factors of 0.636 (5):0.364 (5) and 0.832 (5):0.168 (5). The crystal structure features weak C-H⋯O hydrogen bonds.

  6. (1S,3R,8R)-9-(1-Amino-ethyl-idene)-2,2-dichloro-3,7,7-trimethyl-tricyclo-[6.4.0.0]undecan-10-one.

    Science.gov (United States)

    Benharref, Ahmed; Lassaba, Essêdiya; Avignant, Daniel; Oudahmane, Abdelghani; Berraho, Moha

    2011-02-16

    The title compound, C(16)H(23)Cl(2)NO, was synthesised from β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzocyclo-heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The mol-ecule contains a seven membered ring, which is fused to a five- and a three-membered ring. The five-membered ring has a twisted conformation, whereas the seven-membered ring displays a chair conformation. The dihedral angle between the five- and seven-membered rings is 45.26 (9)°. The absolute structure was established unambiguously from anomalous dispersion effects. In the crystal, mol-ecules are linked into chains propagating along the b axis by inter-molecular N-H⋯O hydrogen bonds; an intramolecular N-H⋯O link also occurs.

  7. trans-Bis(acetato-κO)bis-(2-amino-ethanol-κ(2)N,O)nickel(II).

    Science.gov (United States)

    Seifollahi Bazarjani, Mahdi; Foro, Sabine; Donner, Wolfgang; Gurlo, Aleksander; Riedel, Ralf

    2012-05-01

    In the title compound, [Ni(CH(3)CO(2))(2)(C(2)H(7)NO)(2)], the Ni(II) cation, located on an inversion center, is N,O-chelated by two 2-amino-ethanol mol-ecules and further coordinated by two monodendate acetate anions in a slightly distorted octa-hedral geometry. The latter is stabilized by intra-molecular O-H⋯O hydrogen bonds involving the non-coordinated O atom of the acetate and the H atom of the hy-droxy group of the 2-amino-ethanol ligand. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional supra-molecular framework that involves (a) the coordinated acetate O atom and one of the H atoms of the amino group and (b) the non-coordinated acetate O atom and the other H atom of the amino group.

  8. N-(2-Chloro-phen-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-08-01

    In the title compound, C(12)H(9)ClN(2)O(4)S, the N-H bond in the -SO(2)-NH- segment is syn to both the ortho-nitro group in the sulfonyl-benzene ring and the ortho-Cl atom in the aniline ring. The mol-ecule is twisted at the S-N bond with a torsion angle of 75.0 (2)°. The dihedral angle between the sulfonyl-benzene and aniline rings is 54.97 (11)°. The amide H atom shows bifurcated hydrogen bonding, generating S(7) and C(4) motifs. In the crystal, N-H⋯O(S) hydrogen bonds link the mol-ecules into chains.

  9. N-(4-Chloro-3-nitro-phen-yl)maleamic acid.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-03-01

    In the mol-ecule of the title compound, C(10)H(7)ClN(2)O(5), the acyclic C=C double bond is cis configured. The C=O and O-H bonds of the acid group are in a relatively rare anti position to each other, due to the donation of intramolecular hydrogen bond to the amide by the carboxyl group. The nitro group is significantly twisted [dihedral angle = 66.9 (3)°] out of the plane of the remaining atoms, which are almost coplanar (r.m.s. deviation for non-H atoms except the nitro group = 0.202 Å). In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into zigzag chains running along the b axis.

  10. N-(2,3-Dichloro-phen-yl)-2-nitro-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2013-01-01

    In the title compound, C12H8Cl2N2O4S, the N-C bond in the C-SO2-NH-C segment has gauche torsions with respect to the S=O bonds. Further, the N-H bond is syn to the ortho-nitro group in the sulfonyl benzene ring and also syn to both the ortho- and meta-Cl atoms in the aniline ring. The mol-ecule is twisted at the S-N bond with a torsion angle of 61.15 (18)°. The dihedral angle between the planes of the benzene rings is 68.00 (6)°. The amide H atom exhibits an intra-molecular bifurcated N-H⋯(O,O) hydrogen bond. In the crystal, pairs of N-H⋯O(S) hydrogen bonds link the mol-ecules into inversion dimers with R2(2)(8) motifs.

  11. 2-Nitro-N-phenyl-benzene-sulfonamide.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-09-01

    In the title compound, C(12)H(10)N(2)O(4)S, the conformation of the N-H bond in the -SO(2)-NH- fragment is syn to the ortho-nitro group in the sulfonyl-benzene ring. The mol-ecule is twisted at the S-N bond, the C-N-S-C torsion angle being -72.83 (15)°. The dihedral angle between the benzene rings is 59.55 (7)°. The amide H atom and the nitro group O atom form an intra-molecular hydrogen bond, generating an S(7) motif. In the crystal, C-H⋯O hydrogen-bond inter-actions link the mol-ecules into S(2) (2)(10) networks.

  12. Tetra-aqua-bis[(1-ammonio-1-phosphono-ethyl)phospho-nato]zinc(II) tetra-hydrate.

    Science.gov (United States)

    Dudko, A; Bon, V; Kozachkova, A; Pekhnyo, V

    2009-03-28

    The title compound, [Zn(C(2)H(8)NO(6)P(2))(2)(H(2)O)(4)]·4H(2)O, was synthesized by the reaction of ZnCl(2) with 1-amino-ethane-1,1-diyldiphospho-nic acid in aqueous solution. The asymmetric unit contains one-half of the complex and two water mol-ecules of solvation. The Zn atom occupies a special position on an inversion centre. This results in a slightly distorted octa-hedral coordination environment, which consists of the O atoms from two phospho-nic acids and four water mol-ecules. The crystal structure displays N-H⋯O and O-H⋯O hydrogen bonding, which creates a three-dimensional network.

  13. 12-Nitro-methyl-14-deoxy-andro-graph-olide.

    Science.gov (United States)

    Quan, Ji-Cai; Chen, Jing; Xu, Hao; Hu, Chen-Hui; Wang, Jin-Tang

    2008-06-28

    In the mol-ecule of the title compound {systematic name: 3-[2-(6-hydr-oxy-5-hydroxy-methyl-5,8a-dimethyl-2-methyl-ene-per-hydro-1-napth-yl)-1-(nitro-meth-yl)eth-yl]-2(4H)-furan-one}, C(21)H(31)NO(6), the cyclo-hexane rings have chair conformations. Intra-molecular O-H⋯O hydrogen bonding results in the formation of a six-membered non-planar ring with a twist conformation. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into infinite chains along the c axis.

  14. Crystal structure of oxamyl

    Directory of Open Access Journals (Sweden)

    Eunjin Kwon

    2016-12-01

    Full Text Available The title compound, C7H13N3O3S [systematic name: (Z-methyl 2-dimethylamino-N-(methylcarbamoyloxy-2-oxoethanimidothioate], is an oxime carbamate acaride, insecticide and nematicide. The asymmetric unit comprises two independent molecules, A and B. The dihedral angles between the mean planes [r.m.s. deviations = 0.0017 (A and 0.0016 Å (B] of the acetamide and oxyimino groups are 88.80 (8° for A and 87.05 (8° for B. In the crystal, N/C—H...O hydrogen bonds link adjacent molecules, forming chains along the a axis. The chains are further linked by C—H...O hydrogen bonds, resulting in a three-dimensional network with alternating rows of A and B molecules in the bc plane stacked along the a-axis direction. The structure was refined as an inversion twin with a final BASF parameter of 0.16 (9.

  15. N-(4-Methyl-2-nitro-phen-yl)succinamic acid.

    Science.gov (United States)

    Chaithanya, U; Foro, Sabine; Gowda, B Thimme

    2012-03-01

    In the title compound, C(11)H(12)N(2)O(5), the conformation of the N-H bond in the amide segment is syn to the ortho-nitro group in the benzene ring. The amide C=O and the carboxyl C=O of the acid segment are syn to each other and both are anti to the H atoms on the adjacent -CH(2) groups. Furthermore, the C=O and O-H bonds of the acid group are in syn positions with respect to each other. The dihedral angle between the benzene ring and the amide group is 36.1 (1)°. The amide H atom shows bifurcated intra-molecular hydrogen bonding with an O atom of the ortho-nitro group and an inter-molecular hydrogen bond with the carbonyl O atom of another mol-ecule. In the crystal, the N-H⋯O(C) hydrogen bonds generate a chain running along the [100] direction. Inversion dimers are formed via a pair of O-H⋯O(C) interactions, that form an eight-membered hydrogen-bonded ring involving the carboxyl group.

  16. En bloc pancreaticoduodenectomy for right colon cancer invading adjacent organs.

    Science.gov (United States)

    Berrospi, Francisco; Celis, Juan; Ruiz, Eloy; Payet, Eduardo

    2002-03-01

    Surgical treatment of colorectal cancer needs an extended resection of the tumor en block with invaded organs. There is little information about the surgical treatment of right-sided colon carcinoma directly involving duodenum and pancreas. Our objective is to report our experience with three patients who underwent en bloc pancreaticoduodenectomy and hemicolectomy for locally advanced right colon cancer. Retrospective review of clinical records of patients with colon cancer. Three patients with right colon cancer adherent to adjacent organs underwent en block surgery. No operative deaths occurred. All patients are alive without evidence of disease at 10, 30, 113 months of follow-up, respectively. Locally advanced right-sided colon cancer can be safely treated with en bloc pancreaticoduodenectomy and colectomy with excellent long-term results. Copyright 2002 Wiley--Liss, Inc.

  17. Adjacent Lumbar Disc Herniation after Lumbar Short Spinal Fusion

    Directory of Open Access Journals (Sweden)

    Koshi Ninomiya

    2014-01-01

    Full Text Available A 70-year-old outpatient presented with a chief complaint of sudden left leg motor weakness and sensory disturbance. He had undergone L4/5 posterior interbody fusion with L3–5 posterior fusions for spondylolisthesis 3 years prior, and the screws were removed 1 year later. He has been followed up for 3 years, and there had been no adjacent segment problems before this presentation. Lumbar magnetic resonance imaging (MRI showed a large L2/3 disc hernia descending to the L3/4 level. Compared to the initial MRI, this hernia occurred in an “intact” disc among multilevel severely degenerated discs. Right leg paresis and bladder dysfunction appeared a few days after admission. Microscopic lumbar disc herniotomy was performed. The right leg motor weakness improved just after the operation, but the moderate left leg motor weakness and difficulty in urination persisted.

  18. An optimization study for viscous dampers between adjacent buildings

    Science.gov (United States)

    Kandemir-Mazanoglu, Elif Cagda; Mazanoglu, Kemal

    2017-05-01

    This paper investigates optimum viscous damper capacity and number for prevention of one-sided structural pounding between two adjacent buildings under earthquake motion. The buildings assumed as shear-type structures are modeled by using lumped mass-stiffness technique. Impact forces due to pounding is simulated by nonlinear elastic spring approximation called Hertz model. A parametric study is conducted by varying storey number and stiffness of buildings in addition to the capacity of the viscous dampers. Pounding force and supplemental damping ratio for each case are presented based upon newly defined nondimensional natural frequency parameter ratio. An optimization procedure for determination of viscous damper capacity is developed based on modified supplemental damping ratio equation. Results are compared with each other to clarify the effect of variation in building parameters on pounding forces and viscous damper capacity.

  19. Configuration optimization of dampers for adjacent buildings under seismic excitations

    Science.gov (United States)

    Bigdeli, Kasra; Hare, Warren; Tesfamariam, Solomon

    2012-12-01

    Passive coupling of adjacent structures is known to be an effective method to reduce undesirable vibrations and structural pounding effects. Past results have shown that reducing the number of dampers can considerably decrease the cost of implementation and does not significantly decrease the efficiency of the system. The main objective of this study was to find the optimal arrangement of a limited number of dampers to minimize interstorey drift. Five approaches to solving the resulting bi-level optimization problem are introduced and examined (exhaustive search, inserting dampers, inserting floors, locations of maximum relative velocity and a genetic algorithm) and the numerical efficiency of each method is examined. The results reveal that the inserting damper method is the most efficient and reliable method, particularly for tall structures. It was also found that increasing the number of dampers does not necessarily increase the efficiency of the system. In fact, increasing the number of dampers can exacerbate the dynamic response of the system.

  20. Acyclic 6-choosability of planar graphs without adjacent short cycles

    Institute of Scientific and Technical Information of China (English)

    WANG WeiFan; ZHANG Ge; CHEN Min

    2014-01-01

    A proper vertex coloring of a graph G is acyclic if G contains no bicolored cycles.Given a list assignment L={L(v)|v∈V}of G,we say that G is acyclically L-colorable if there exists a proper acyclic coloringπof G such thatπ(v)∈L(v)for all v∈V.If G is acyclically L-colorable for any list assignment L with|L(v)|k for all v∈V(G),then G is acyclically k-choosable.In this paper,we prove that every planar graph G is acyclically 6-choosable if G does not contain 4-cycles adjacent to i-cycles for each i∈{3,4,5,6}.This improves the result by Wang and Chen(2009).

  1. Soil Structure Interaction between Two Adjacent Buildings under Earthquake Load

    Directory of Open Access Journals (Sweden)

    Mahmoud Yahyai

    2008-01-01

    Full Text Available In some cases, tall buildings are located in geotechnically unsuitable places, due to their high ratio of height to width; there is risk of uplift and other effects such as overturning and reduction structure serviceability during earthquake. This research is aimed to evaluate the effect of Soil-Structure Interaction (SSI on seismic behavior of two adjacent 32 story buildings such as time period, base shear and displacements. The interaction effects are investigated for variable distance between the two buildings. Three types of soil such as soft clay, sandy gravel and compacted sandy gravel are considered for this study. The result obtained that the interaction effect increases time period of both buildings base shear and lateral displacement of the structures increases.

  2. Analysis of blasting damage in adjacent mining excavations

    Directory of Open Access Journals (Sweden)

    Nick Yugo

    2015-06-01

    Full Text Available Following a small-scale wedge failure at Yukon Zinc's Wolverine Mine in Yukon, Canada, a vibration monitoring program was added to the existing rockbolt pull testing regime. The failure in the 1150 drift occurred after numerous successive blasts in an adjacent tunnel had loosened friction bolts passing through an unmapped fault. Analysis of blasting vibration revealed that support integrity is not compromised unless there is a geological structure to act as a failure plane. The peak particle velocity (PPV rarely exceeded 250 mm/s with a frequency larger than 50 Hz. As expected, blasting more competent rock resulted in higher PPVs. In such cases, reducing the round length from 3.5 m to 2.0 m was an effective means of limiting potential rock mass and support damage.

  3. Adjacent Vertex Distinguishing Incidence Coloring of the Cartesian Product of Some Graphs

    Institute of Scientific and Technical Information of China (English)

    Qian WANG; Shuang Liang TIAN

    2011-01-01

    An adjacent vertex distinguishing incidence coloring of graph G is an incidence coloring of G such that no pair of adjacent vertices meets the same set of colors. We obtain the adjacent vertex distinguishing incidence chromatic number of the Cartesian product of a path and a path, a path and a wheel, a path and a fan, and a path and a star.

  4. ZOOGEOGRAPHICAL ZONING OF THE MEDITERRANEAN AND ADJACENT TERRITORIES

    Directory of Open Access Journals (Sweden)

    H. A. Ketenchiev

    2013-01-01

    Full Text Available Abstract. Aim. The article considers the zoogeographical zoning of the Mediterranean and adjacent territories with the purpose of specification of the scheme of zoogeographic zoning of land on the basis of the distribution of dragonflies.Methods. Use common methods of entomological research, mapping and analysis of the fauna.Results. On the based on our analysis of the composition and distribution of odonatofauna Mediterranean zoogeographical subregion is offered to divide into 5 provinces: Caucasian, South-European, Pyrenees, Asian and African. Analysis of the existing schemes zoning of land based on the distribution of taxa dragonflies, installed the advantages and disadvantages presented by different authors, the result of which is proposed to change the borders between the Holarctic and Subholarctic areas of the Boreal fauna Kingdom (BFK. It is connected with the fact that the dividing them into subdomains and evaluation role in the establishment of regional odonatofauna not always convincing. In this regard, the article proposed to abolish the Holarctic region sub-region: European and Mongolian-Kazakh, and in Subholarctic - add 1 sub-region of Central Asia. In a new form Subholarctic region becomes clear and logical configuration, but her name becomes inadequate, therefore, we re-name it in Paleosubtropical.The scope of the results. In fundamental research on systematics of animals, ecology and biogeography.Main conclusions. Based on the study of the composition and distribution of taxa of dragonflies in the Mediterranean and adjacent territories proposed the division of the Mediterranean subregion 5 provinces and refined scheme of zoogeographic zoning of land.

  5. Aqua-(2,2'-bipyridine-κ²N,N')(2-methyl-malonato-κ²O¹,O³)copper(II) dihydrate.

    Science.gov (United States)

    Manochitra, P; Manikandan, N; Murugavel, S; Sreeshailam, R; Sambasiva Rao, P

    2012-07-01

    In the title compound, [Cu(C₄H₄O₄)(C₁₀H₈N₂)(H₂O)]·2H₂O, the Cu(II) ion displays a slightly distorted square-pyramidal coordination. The water mol-ecule at the apical position shows a long bond [Cu-O = 2.276 (2) Å]. The basal plane is formed by two N atoms of the 2,2'-bipyridine ligand and two carboxyl-ate O atoms from a malonate group. The five-membered chelate ring is almost planar [maximum deviation = -0.006 (2) Å], while the six-membered chelate ring defined by the malonate ligand adopts a distorted boat conformation. In the crystal, Cu(II) complex mol-ecules and lattice water mol-ecules are connected by O-H⋯O and C-H⋯O hydrogen bonds. The crystal packing is further stabilized by π-π inter-actions [centroid-centroid distances = 3.563 (2)-3.828 (2) Å].

  6. [μ-Bis(diphenyl-arsino)methane-1:2κAs:As']nona-carbonyl-1κC,2κC,3κC-[diphen-yl(phenyl-sulfanylmeth-yl)phosphine-3κP]-triangulo-triruthenium(0) chloro-form hemisolvate.

    Science.gov (United States)

    Shawkataly, Omar Bin; Khan, Imthyaz Ahmed; Yeap, Chin Sing; Fun, Hoong-Kun

    2010-01-30

    The asymmetric unit of the title triangulo-triruthenium cluster, [Ru(3)(C(25)H(22)As(2))(C(19)H(17)PS)(CO)(9)]·0.5CHCl(3), contains of one mol-ecule of the triangulo-triruthenium complex and half a mol-ecule of the disordered (two positions of equal weight) chloro-form solvent. The bis-(diphenyl-arsino)methane ligand bridges an Ru-Ru bond and the monodentate phosphine ligand bonds to the third Ru atom. Both the arsine and phosphine ligands are equatorial with respect to the Ru(3) triangle. In addition, each Ru atom carries one equatorial and two axial terminal carbonyl ligands. The benzene ring of phenyl-thio-methyl is disordered over two positions with refined site occupancies of 0.788 (11) and 0.212 (11). In the crystal packing, mol-ecules are linked into chains along b axis by inter-molecular C-H⋯O hydrogen bonds. Weak inter-molecular C-H⋯π inter-actions further stabilize the crystal structure.

  7. [μ-Bis(diphenyl-arsino)methane-1:2κAs:As']nona-carbonyl-1κC,2κC,3κC-[(penta-fluoro-phen-yl)diphenyl-phosphine-3κP]-triangulo-triruthenium(0) chloro-form monosolvate.

    Science.gov (United States)

    Shawkataly, Omar Bin; Khan, Imthyaz Ahmed; Yeap, Chin Sing; Fun, Hoong-Kun

    2010-01-16

    The asymmetric unit of the title triangulo-triruthenium compound, [Ru(3)(C(25)H(22)As(2))(C(18)H(10)F(5)P)(CO)(9)]·CHCl(3), contains one mol-ecule of the triangulo-triruthenium complex and one mol-ecule of the disordered chloro-form solvent. The bis-(diphenyl-arsino)methane ligand bridges an Ru-Ru bond and the monodentate phosphine ligand bonds to the third Ru atom. Both the arsine and phosphine ligands are equatorial with respect to the Ru(3) triangle. In addition, each Ru atom carries one equatorial and two axial terminal carbonyl ligands. The phosphine-substituted benzene rings make dihedral angles of 68.43 (15), 65.14 (14) and 89.75 (14)° with each other. The dihedral angles between the two benzene rings are 80.70 (15) and 84.53 (16)° for the two diphenyl-arsino groups. In the crystal packing, the mol-ecules are linked into a plane parallel to bc by inter-molecular C-H⋯O and C-H⋯F hydrogen bonds. Weak inter-molecular C-H⋯π inter-actions further stabilize the crystal structure.

  8. Increased oxidative DNA damage seen in renal biopsies adjacent stones in patients with nephrolithiasis.

    Science.gov (United States)

    Kittikowit, Wipawee; Waiwijit, Uraiwan; Boonla, Chanchai; Ruangvejvorachai, Preecha; Pimratana, Chaowat; Predanon, Chagkrapan; Ratchanon, Supoj; Tosukhowong, Piyaratana

    2014-10-01

    Urinary excretion of 8-hydroxydeoxyguanosine (8-OHdG), a marker of oxidative DNA damage, is significantly higher in nephrolithiasis patients than in healthy individuals, indicating that these patients have higher degree of oxidative stress. In the present study, we investigated 8-OHdG expression in renal biopsies of patients with nephrolithiasis and in renal tubular cells (HK-2 cells) exposed to calcium oxalate monohydrate (COM). We performed immunohistochemical staining for 8-OHdG in renal biopsies adjacent stones obtained from 28 patients with nephrolithiasis. Controls were noncancerous renal tissues from nephrectomies of patients with renal cancer. 8-OHdG was overexpressed in the nucleus of renal tubular cells in patients with nephrolithiasis compared with controls. Only one nephrolithiasis biopsy was negative for 8-OHdG, whereas in 19 cases 8-OHdG was highly expressed. The level of expression of 8-OHdG among patients with calcium oxalate (mostly mixed with calcium phosphate) and uric acid stones was not significantly different. Increased leukocyte infiltration was observed in renal tissues from patients with nephrolithiasis. Exposure of HK-2 cells to COM caused increased intracellular reactive oxygen species and nuclear expression of 8-OHdG. To our knowledge, this is the first report of increased 8-OHdG expression in renal tubular cells of patients with nephrolithiasis. In vitro, COM crystals were capable of inducing oxidative damage of DNA in the proximal renal tubular cells.

  9. Characterization of calcium lactate crystals on cheddar cheese by image analysis.

    Science.gov (United States)

    Rajbhandari, P; Kindstedt, P S

    2008-06-01

    Previous research demonstrated that crystal coverage on the surface of Cheddar cheese can be quantitatively and nondestructively measured using image analysis of digital photographs of the cheese surface. The objective of the present study was to extend image analysis methodology to quantify and characterize additional features of visible crystals on cheese surfaces as they grow over time. A random weight (approximately 300 g) retail sample of naturally smoked Cheddar cheese exhibiting white surface crystals was obtained from a commercial source. The total area occupied by crystals and total number of discrete crystal regions on one of the surfaces (approximately 55 x 120 mm) was measured at 3-wk intervals for 30 wk using image analysis. In addition, 5 small (approximately 0.3 mm radius) individual crystals on that surface were chosen for observation over the 30-wk period. The crystals were evaluated for area, radius, and shape factor (circularity) every third week using image analysis. The total area occupied by crystals increased in a linear manner (R(2) = 0.95) from about 0.44 to 7.42% of the total cheese surface area over the 30-wk period. The total number of discrete crystal regions also increased but in a nonlinear manner that was best described by a quadratic relationship. Measurement of discrete crystal regions underestimated the true number of crystals present at the cheese surface due to merging of adjacent crystals as they grew and merged into a single crystal region over time. Throughout this period, the shapes of the 5 individual crystals closely approximated perfect circles, except when adjacent crystals merged to form a single irregular crystal region, and the area occupied by each of the 5 crystals increased in a near-linear manner (R(2) = 0.95). Image analysis approaches may be used to evaluate crystal formation and growth rates and morphology on cheese.

  10. Biological Macromolecule Crystallization Database

    Science.gov (United States)

    SRD 21 Biological Macromolecule Crystallization Database (Web, free access)   The Biological Macromolecule Crystallization Database and NASA Archive for Protein Crystal Growth Data (BMCD) contains the conditions reported for the crystallization of proteins and nucleic acids used in X-ray structure determinations and archives the results of microgravity macromolecule crystallization studies.

  11. Crystal structure of 9-methacryloylanthracene

    Directory of Open Access Journals (Sweden)

    Aditya Agrahari

    2015-04-01

    Full Text Available In the title compound, C18H14O, with systematic name 1-(anthracen-9-yl-2-methylprop-2-en-1-one, the ketonic C atom lies 0.2030 (16 Å out of the anthryl-ring-system plane. The dihedral angle between the planes of the anthryl and methacryloyl moieties is 88.30 (3° and the stereochemistry about the Csp2—Csp2 bond in the side chain is transoid. In the crystal, the end rings of the anthryl units in adjacent molecules associate in parallel–planar orientations [shortest centroid–centroid distance = 3.6320 (7 Å]. A weak hydrogen bond is observed between an aromatic H atom and the O atom of a molecule displaced by translation in the a-axis direction, forming sheets of parallel-planar anthryl groups packing in this direction.

  12. Hydrocarbon provinces and productive trends in Libya and adjacent areas

    Energy Technology Data Exchange (ETDEWEB)

    Missallati, A.A. (Agip (N.A.M.E.)Ltd., Tripoli (Libya))

    1988-08-01

    According to the age of major reservoirs, hydrocarbon occurrences in Libya and adjacent areas can be grouped into six major systems which, according to their geographic locations, can be classified into two major hydrocarbon provinces: (1) Sirte-Pelagian basins province, with major reservoirs ranging from middle-late Mesozoic to early Tertiary, and (2) Murzog-Ghadames basins province, with major reservoirs ranging from early Paleozoic to early Mesozoic. In the Sirte-Pelagian basins province, hydrocarbons have been trapped in structural highs or in stratigraphic wedge-out against structural highs and in carbonate buildups. Here, hydrocarbon generation is characterized by the combined effect of abundant structural relief and reservoir development in the same hydrocarbon systems of the same age, providing an excellent example of hydrocarbon traps in sedimentary basins that have undergone extensive tensional fracturing in a shallow marine environment. In the Murzog-Ghadames basins province, hydrocarbons have been trapped mainly in structural highs controlled by paleostructural trends as basement arches which acted as focal points for oil migration and accumulation.

  13. Repeated adjacent-segment degeneration after posterior lumbar interbody fusion.

    Science.gov (United States)

    Okuda, Shinya; Oda, Takenori; Yamasaki, Ryoji; Maeno, Takafumi; Iwasaki, Motoki

    2014-05-01

    One of the most important sequelae affecting long-term results is adjacent-segment degeneration (ASD) after posterior lumbar interbody fusion (PLIF). Although several reports have described the incidence rate, there have been no reports of repeated ASD. The purpose of this report was to describe 1 case of repeated ASD after PLIF. A 62-year-old woman with L-4 degenerative spondylolisthesis underwent PLIF at L4-5. At the second operation, L3-4 PLIF was performed for L-3 degenerative spondylolisthesis 6 years after the primary operation. At the third operation, L2-3 PLIF was performed for L-2 degenerative spondylolisthesis 1.5 years after the primary operation. Vertebral collapse of L-1 was detected 1 year after the third operation, and the collapse had progressed. At the fourth operation, 3 years after the third operation, vertebral column resection of L-1 and replacement of titanium mesh cages with pedicle screw fixation between T-4 and L-5 was performed. Although the patient's symptoms resolved after each operation, the time between surgeries shortened. The sacral slope decreased gradually although each PLIF achieved local lordosis at the fused segment.

  14. Seismic motion attenuation relations in Sichuan and adjacent areas

    Institute of Scientific and Technical Information of China (English)

    LEI Jian-cheng; GAO Meng-tan; YU Yan-xiang

    2007-01-01

    The Sichuan and adjacent areas is divided into southwest China region (SWCR) and Sichuan Basin region (SCBR) according to tectonic backgrounds and seismic damage distribution features. 96 modern destructive earthquakes in SWCR and 40 in SCBR are gathered respectively. All their magnitude parameters are checked. Based on the statistic relations between epicentral intensity and magnitude as well as relation between sensible radius and magnitude, the near and far field seismic intensity attenuation features are represented and controlled. And then the seismic intensity attenuation relations along major axis, minor axis and mean axis are established separately. The systematic deviations of surface wave magnitude between China seismograph network and U.S. seismograph network are considered in this paper. By making use of the new attenuation relations of bedrock horizontal ground acceleration response spectrum in west U.S., the attenuation relations of bedrock horizontal ground acceleration response spectrum in SWCR and SCBR are digital transformed based on the attenuation model considering acceleration saturation of distance and magnitude in near field.

  15. The Current Tectonics of the Yukon and Adjacent Area

    Science.gov (United States)

    Hyndman, R. D.; Leonard, L. J.

    2014-12-01

    The current tectonics across the Yukon and adjacent areas of western Northwest Territories (NWT) and northern British Columbia appear to be driven primarily by the Yakutat Terrane collision, an "indenter" in the corner of the Gulf of Alaska. GPS data show 1-10 mm/yr northward and eastward, decreasing inland. The rates from earthquake statistics are similar although there are important discrepancies. The eastern Cordillera earthquake mechanisms are mainly thrust in the Mackenzie Mountains of southwestern NWT where the Cordillera upper crust is overthrusting the craton. To the north, the mechanisms are mainly strike-slip in the Richardson Mountains that appear to lie along the edge of the craton. The deformation appears to be limited to the hot and weak Cordillera with the strong craton providing an irregular eastern boundary. For example, there is an eastward bow in the craton edge and the deformation in the Mackenzie Mountains. On the Beaufort Sea margin in the region of the Mackenzie Delta there appears to be a type of "subduction zone" with the continent very slowly overthrusting the oceanic plate, a process that has continued since at least the Cretaceous. A northward moving continental margin block is bounded by left lateral faulting in the west (Canning Displacement Zone of eastern Alaska) and right lateral faulting in the east (Richardson Mountains in eastern Yukon). There is almost no seismicity on this thrust belt but as for some other subduction zones such as Cascadia there is the potential for very infrequent great earthquakes.

  16. Stereotactic radiotherapy using Novalis for craniopharyngioma adjacent to optic pathways.

    Science.gov (United States)

    Hashizume, Chisa; Mori, Yoshimasa; Kobayashi, Tatsuya; Shibamoto, Yuta; Nagai, Aiko; Hayashi, Naoki

    2010-06-01

    Craniopharyngioma has benign histological character. However, because of proximity to optic pathways, pituitary gland, and hypothalamus, it may cause severe and permanent damage to such critical structures and can even be life threatening. Total surgical resection is often difficult. This study aims to evaluate treatment results of Novalis stereotactic radiotherapy (SRT) for craniopharyngioma adjacent to optic pathways. Ten patients (six men, four women) with craniopharyngioma and median age of 56.5 years (range 10-74 years) were treated by SRT using Novalis from July 2006 through March 2009. Median volume of tumor was 7.9 ml (range 1.1-21 ml). Three-dimensional noncoplanar five- or seven-beam SRT or coplanar five-beam SRT with intensity modulation was performed. Total dose of 30-39 Gy in 10-15 fractions (median 33 Gy) was delivered to the target. Ten patients were followed up for 9-36 months (median 25.5 months). Response rate was 80% (8/10), and control rate was 100%. Improvement of neurological symptoms was observed in five patients. No serious complications due to SRT were found. SRT for craniopharyngioma may be a safe and effective treatment. Longer follow-up is necessary to determine long-term tumor control or late complications.

  17. Adjacent level spondylodiscitis after anterior cervical decompression and fusion

    Directory of Open Access Journals (Sweden)

    Saumyajit Basu

    2012-01-01

    Full Text Available Postoperative spondylodiscitis after anterior cervical decompression and fusion (ACDF is rare, but the same occurring at adjacent levels without disturbing the operated level is very rare. We report a case, with 5 year followup, who underwent ACDF from C5 to C7 for cervical spondylotic myelopathy. He showed neurological improvement after surgery but developed discharging sinus after 2 weeks, which healed with antibiotics. He improved on his preoperative symptoms well for the first 2 months. He started developing progressive neck pain and myelopathy after 3 months and investigations revealed spondylodiscitis at C3 and C4 with erosion, collapse, and kyphosis, without any evidence of implant failure or graft rejection at the operated level. He underwent reexploration and implant removal at the operated level (there was good fusion from C5 to C7 followed by debridement/decompression at C3, C4 along with iliac crest bone grafting and stabilization with plate and screws after maximum correction of kyphosis. The biopsy specimen grew Pseudomonas aeruginosa and appropriate sensitive antibiotics (gentamycin and ciprofloxacin were given for 6 weeks. He was under regular followup for 5 years his myelopathy resolved completely and he is back to work. Complete decompression of the cord and fusion from C2 to C7 was demonstrable on postoperative imaging studies without any evidence of implant loosening or C1/C2 instability at the last followup.

  18. Ribbon crystals.

    Directory of Open Access Journals (Sweden)

    Jakob Bohr

    Full Text Available A repetitive crystal-like pattern is spontaneously formed upon the twisting of straight ribbons. The pattern is akin to a tessellation with isosceles triangles, and it can easily be demonstrated with ribbons cut from an overhead transparency. We give a general description of developable ribbons using a ruled procedure where ribbons are uniquely described by two generating functions. This construction defines a differentiable frame, the ribbon frame, which does not have singular points, whereby we avoid the shortcomings of the Frenet-Serret frame. The observed spontaneous pattern is modeled using planar triangles and cylindrical arcs, and the ribbon structure is shown to arise from a maximization of the end-to-end length of the ribbon, i.e. from an optimal use of ribbon length. The phenomenon is discussed in the perspectives of incompatible intrinsic geometries and of the emergence of long-range order.

  19. Crystal structure of an organic-inorganic hybrid compound based on morpholinium cations and a β-type Anderson polyanion.

    Science.gov (United States)

    Lukianova, Tamara J; Kinzhybalo, Vasyl; Pietraszko, Adam

    2015-11-01

    A new organic-inorganic hybrid compound, penta-morpholinium hexa-hydrogen hexa-molybdoferrate(III) sulfate 3.5-hydrate, (C4H10NO)5[Fe(III)(OH)6Mo6O18](SO4)·3.5H2O, was obtained from an aqueous solution. The polyoxidomolybdate (POM) anion is of the Anderson β-type with a central Fe(III) ion. Three of five crystallographically independent morpholinium cations are disordered over two sets of sites. An intricate network of inter-molecular N-H⋯O and O-H⋯O inter-actions between cations, POMs, sulfate anions and non-coordinating water mol-ecules creates a three-dimensional network structure.

  20. 5-Acetyl-4-(3-hy-droxy-phen-yl)-6-methyl-1,2,3,4-tetra-hydro-pyrimidin-2-one-tris-(hy-droxy-meth-yl)ammonium chloride (2/1).

    Science.gov (United States)

    Huq, C A M A; Fouzia, S; Nizammohideen, M

    2013-11-13

    The asymmetric unit of the title compound, 2C13H14N2O3·C3H10NO3 (+)·Cl(-), contains two independent mol-ecules (A and B) of the title pyrimidine derivative and one ion-pair of tris-(hy-droxy-meth-yl)ammonium chloride. The pyrimidine ring in each pyrimidine derivative has a half-chair conformation. Its mean plane is inclined to the benzene ring by 87.2 (3)° in mol-ecule A and 85.7 (2)° in mol-ecule B. In the crystal, the pyrimidine derivatives are connected to each other by N-H⋯O hydrogen bonds, forming chains propagating along the b-axis direction. The chains are linked via O-H-Cl hydrogen bonds, forming corrugated sheets lying parallel to the bc plane. The sheets are linked via C-H⋯O hydrogen bonds, forming a three-dimensional framework. The tris-(hy-droxy-meth-yl)ammonium chloride mol-ecules are located in the cages of the framework. There are also further C-H⋯O hydrogen bonds and C-H⋯π inter-actions present in the three-dimensional framework structure. Both the cation and chloride anion of the tris-(hy-droxy-meth-yl)ammonium chloride ion pair are disordered over two positions, with a refined occupancy ratio of 0.418 (8):0.582 (8) for the cation and 0.71 (4):0.29 (4) for the anion.

  1. Poly[[μ(2)-aqua-tetraaquadi-μ(3)-malonato-nickel(II)strontium(II)] dihydrate].

    Science.gov (United States)

    Guo, Ming-Lin; Liu, Long; Lu, Cong-Cong

    2010-12-04

    The unit-cell parameters for the title mixed-metal coordination polymer, {[NiSr(C(3)H(2)O(4))(2)(H(2)O)(5)]·2H(2)O}(n), which is isostructural with its Co-containing analogue, were reported previously [Gil de Muro et al. (1999 ▶). Eur. J. Inorg. Chem. pp. 935-943]; the full crystal structure including a description of the hydrogen bonding is reported here. The Sr(2+) ion is bonded to five O atoms from three different malonate dianions and four water mol-ecules, displaying a distorted tricapped trigonal-prismatic coordination geometry. Two malonate dianions, two water mol-ecules and one Ni(2+) ion build up a dianionic [Ni(C(3)H(2)O(4))(2)(H(2)O)(2)](2-) unit incorporating a slightly distorted NiO(6) octa-hedron, which coordinates to three nearby Sr(2+) ions. This arrangement creates a metal-organic framework having a 20-membered ring with four Ni and six Sr atoms lying in the bc plane. The coordinated and uncoordinated water mol-ecules are responsible for the formation of two D5 hydrogen-bonded water chains within the 20-membered ring and they are linked into an R4 water cluster via two bifurcated O-H⋯(O,O) links.

  2. n-Butyldichlorido{4-cyclo-hexyl-1-[1-(pyridin-2-yl-κN)ethyl-idene]thio-semi-carb-azi-dato-κ²N¹,S}tin(IV).

    Science.gov (United States)

    Affan, Md Abu; Salam, Md Abdus; Asaruddin, Mohd Razip; Ng, Seik Weng; Tiekink, Edward R T

    2012-07-01

    Two independent mol-ecules comprise the asymmetric unit in the title compound, [Sn(C₄H₉)(C₁₄H₁₉N₄S)Cl₂]. In each mol-ecule, the Sn(IV) atom exists within a distorted octa-hedral geometry defined by the N,N',S-tridentate mono-deprotonated Schiff base ligand, two mutually trans Cl atoms, and the α-C atom of the n-butyl group; the latter is trans to the azo-N atom. The greatest distortion from the ideal geometry is found in the nominally trans angle formed by the S and pyridyl-N atoms at Sn [151.72 (7) and 152.04 (7)°, respectively]. In the crystal, mol-ecules are consolidated into a three-dimensional architecture by a combination of N-H⋯Cl, C-H⋯π and π-π inter-actions [inter-centroid distances = 3.6718 (19) and 3.675 (2) Å].

  3. [μ-Bis(diphenyl-arsino)methane-1:2κAs:As'][(4-bromo-phen-yl)diphenyl-phosphine-3κP]nona-carbonyl-1κC,2κC,3κC-triangulo-tri-ruthenium(0) chloro-form 0.3-solvate.

    Science.gov (United States)

    Shawkataly, Omar Bin; Khan, Imthyaz Ahmed; Yeap, Chin Sing; Fun, Hoong-Kun

    2010-01-16

    The asymmetric unit of the title triangulo-triruthenium compound, [Ru(3)(C(25)H(22)As(2))(C(18)H(14)BrP)(CO)(9)]·0.3CHCl(3), contains one mol-ecule of the triangulo-triruthenium complex and one partially occupied disordered chloro-form solvent mol-ecule. The bis-(diphenyl-arsino)methane ligand bridges an Ru-Ru bond and the monodentate phosphine ligand bonds to the third Ru atom. Both the arsine and phosphine ligands are equatorial with respect to the Ru(3) triangle. In addition, each Ru atom carries one equatorial and two axial terminal carbonyl ligands. The phosphine-substituted benzene rings make dihedral angles of 67.5 (3), 76.1 (3) and 78.1 (3)° with each other. The dihedral angles between the two benzene rings are 79.0 (4) and 81.4 (3)° for the two diphenyl-arsino groups. In the crystal packing, the mol-ecules are linked into chains along the a axis by inter-molecular C-H⋯O hydrogen bonds.

  4. Benzene-1,3,5-tri-carb-oxy-lic acid-pyridinium-2-olate (1/3).

    Science.gov (United States)

    Campos-Gaxiola, José J; Zamora Falcon, Felipe; Corral Higuera, Ramón; Höpfl, Herbert; Cruz-Enríquez, Adriana

    2014-04-01

    The asymmetric unit of the title compound, C9H6O6·3C5H5NO, contains one benzene-1,3,5-tri-carb-oxy-lic acid mol-ecule (BTA) and three pyridin-2-ol mol-ecules each present in the zwitterion form. In the crystal, these entities are linked through O-H⋯O(-) and N(+)-H⋯O(-) hydrogen bonds, forming sheets parallel to (10-1). These layers contain macrocyclic rings of composition [BTA]2[pyol]6 and with graph-set notation R (6) 8(44), which are stacked along c through π-π inter-actions [inter-centroid distances = 3.536 (2)-3.948 (3) Å]. They are inter-connected by N(+)-H⋯O(-) hydrogen-bonded chains of pyridin-2-ol mol-ecules running parallel to c, forming a three-dimensional network. There are also C-H⋯O hydrogen bonds present which reinforce the three-dimensional structure.

  5. Benzene-1,2,4,5-tetra-carb-oxy-lic acid bis-(1,3,7-trimethyl-2,3,6,7-tetra-hydro-1H-purine-2,6-dione).

    Science.gov (United States)

    Arman, Hadi D; Tiekink, Edward R T

    2013-01-01

    The asymmetric unit of the title co-crystal, C10H6O8·2C8H10N4O2, comprises a centrosymmetric benzene-1,2,4,5-tetra-carb-oxy-lic acid (LH4) mol-ecule and a mol-ecule of caffeine in a general position. LH4 is nonplanar, with the dihedral angles between the ring and pendent carb-oxy-lic acid groups being 44.22 (7) and 49.74 (7)°. By contrast, the caffeine mol-ecule is planar (r.m.s. deviation = 0.040 Å). Supra-molecular layers parallel to (-1-10) are sustained by carb-oxy-lic acid O-H⋯O(carbon-yl) and O-H⋯N(imidazole) hydrogen bonds, as well as by meth-yl-carbonyl C-H⋯O inter-actions. These stack via π-π inter-actions between the benzene and imidazole rings [inter-centroid distance = 3.4503 (10) Å].

  6. 2,3-Dichloro-1,4-hydro-quinone 2,3-dichloro-1,4-benzoquinone monohydrate: a quinhydrone-type 1:1 donor-acceptor [D-A] charge-transfer complex.

    Science.gov (United States)

    Guégano, Xavier; Hauser, Jürg; Liu, Shi-Xia; Decurtins, Silvio

    2011-11-01

    IN THE CRYSTAL STRUCTURE OF THE TITLE COMPOUND (SYSTEMATIC NAME: 2,3-dichloro-benzene-1,4-diol 2,3-dichloro-cyclo-hexa-2,5-diene-1,4-dione monohydrate), C(6)H(4)Cl(2)O(2)·C(6)H(2)Cl(2)O(2)·H(2)O, the 2,3-dichloro-1,4-hydro-quinone donor (D) and the 2,3-dichloro-1,4-benzoquinone acceptor (A) mol-ecules form alternating stacks along [100]. Their mol-ecular planes [maximum deviations for non-H atoms: 0.0133 (14) (D) and 0.0763 (14) Å (A)] are inclined to one another by 1.45 (3)° and are thus almost parallel. There are π-π inter-actions involving the D and A mol-ecules, with centroid-centroid distances of 3.5043 (9) and 3.9548 (9) Å. Inter-molecular O-H⋯O hydrogen bonds involving the water mol-ecule and the hy-droxy and ketone groups lead to the formation of two-dimensional networks lying parallel to (001). These networks are linked by C-H⋯O inter-actions, forming a three-dimensional structure.

  7. 2-Amino-4-methyl-6-oxo-3,6-dihydro-pyrimidin-1-ium perchlorate-2-amino-6-methyl-pyrimidin-4(1H)-one-water (1/1/1).

    Science.gov (United States)

    Kaabi, Kamel; El Glaoui, Maher; Ferretti, Valeria; Zeller, Matthias; Ben Nasr, Cherif

    2011-09-01

    In the title compound, C(5)H(8)N(3)O(+)·ClO(4) (-)·C(5)H(7)N(3)O·H(2)O, each perchlorate anion is paired with a protonated cationic 2-amino-6-methyl-pyrimidin-4(1H)-one and another non-protonated entity of the same organic pyrimidinone. The crystal structure is stabilized by N-H⋯O(org), N-H⋯O(water), N-H⋯O(ClO4), O-H⋯O(ClO4), N-H⋯N and C-H⋯O(ClO4) hydrogen bonds between the anions, organic entities and water mol-ecules. Inter-molecular π-π stacking inter-actions between neighbouring organic rings are observed with a face-to-face distance of 3.776 (2) Å, and O-H⋯O hydrogen bonds link the perchlorate anions and the water mol-ecules into chains along the b-axis direction. The perchlorate anion and the inter-stitial water mol-ecule are disordered over two mutually incompatible positions with a common occupancy ratio of 0.678 (16):0.322 (16).

  8. Poly[[tri-μ-aqua-do-deca-aqua-tris-(μ3-1-hy-droxy-ethyl-idene-1,1-di-phospho-nato)tricalcium(II)tripalladium(II)] penta-hydrate].

    Science.gov (United States)

    Kutsenko, Irina P; Kozachkova, Alexandra N; Tsaryk, Natalia V; Pekhnyo, Vasily I; Rusanova, Julia A

    2014-08-01

    The asymmetric unit of the title compound, {[CaPd{CH3OHC(PO3)2}(H2O)5]·5/3H2O} n , consists of one half of the complex [Pd{CH3OHC(PO3)2}](2-) anion (point group symmetry m..), one Ca(2+) cation [site symmetry (.2.)] that is surrounded by three water mol-ecules (one of which is on the same rotation axis) and by three disordered lattice water mol-ecules. The anions form a trinuclear metallocycle around a crystallographic threefold rotation axis. The cations are related by a twofold rotation axis to form a [Ca2(H2O)10](2+) dimer. The slightly distorted square-planar coordination environment of the Pd(II) atoms in the complex anions is formed by O atoms of the bidentate chelating phospho-nate groups of the 1-hy-droxy-ethyl-idene-1,1-di-phospho-nate ligands. In the crystal, cations are bound to anions through -Ca-O-P-O- bonds, as well as through O-H⋯O hydrogen bonds, resulting in a three-dimensional polymer. The structure is completed by five disordered solvent mol-ecules localized in cavities within the framework.

  9. Wall shear stress in intracranial aneurysms and adjacent arteries

    Institute of Scientific and Technical Information of China (English)

    Fuyu Wang; Bainan Xu; Zhenghui Sun; Chen Wu; Xiaojun Zhang

    2013-01-01

    Hemodynamic parameters play an important role in aneurysm formation and growth. However, it is difficult to directly observe a rapidly growing de novo aneurysm in a patient. To investigate possible associations between hemodynamic parameters and the formation and growth of intracranial aneurysms, the present study constructed a computational model of a case with an internal carotid artery aneurysm and an anterior communicating artery aneurysm, based on the CT angiography findings of a patient. To simulate the formation of the anterior communicating artery aneurysm and the growth of the internal carotid artery aneurysm, we then constructed a model that virtually removed the anterior communicating artery aneurysm, and a further two models that also progressively decreased the size of the internal carotid artery aneurysm. Computational simulations of the fluid dynamics of the four models were performed under pulsatile flow conditions, and wall shear stress was compared among the different models. In the three aneurysm growth models, increasing size of the aneurysm was associated with an increased area of low wall shear stress, a significant decrease in wall shear stress at the dome of the aneurysm, and a significant change in the wall shear stress of the parent artery. The wall shear stress of the anterior communicating artery remained low, and was significantly lower than the wall shear stress at the bifurcation of the internal carotid artery or the bifurcation of the middle cerebral artery. After formation of the anterior communicating artery aneurysm, the wall shear stress at the dome of the internal carotid artery aneurysm increased significantly, and the wall shear stress in the upstream arteries also changed significantly. These findings indicate that low wall shear stress may be associated with the initiation and growth of aneurysms, and that aneurysm formation and growth may influence hemodynamic parameters in the local and adjacent arteries.

  10. Multi-track Storage of 10000 Holograms in a Disk-Type Photorefractive Crystal

    Institute of Scientific and Technical Information of China (English)

    TAO Shi-Quan; XU Min; LIU Guo-Qing; YUAN Quan; JIANG Zhu-Qing

    2000-01-01

    Three-dimensional disk-type holographic storage using spatioangular multiplexing with a spherical reference beam is analyzed and experimentally demonstrated. The overlapping factors between adjacent holograms in a track and between adjacent tracks in a disk are determined based on the selective angles calculated by coupled-wave theory. There are 10000 holograms stored along 5 tracks in a sector of a single iron-doped lithium niobate crystal.

  11. Adjacent tooth trauma in complicated mandibular third molar surgery: Risk degree classification and digital surgical simulation

    Science.gov (United States)

    Ye, Zhou-Xi; Yang, Chi; Ge, Jing

    2016-01-01

    Analysis of adjacent tooth resistance is essential in wisdom teeth extraction to prevent adjacent tooth trauma, however it lacks adequate attention nowadays. This study aims at suggesting special extraction methods based on adjacent tooth resistance analysis for prevention of adjacent tooth damage. In this study, 136 complicated mandibular third molars extracted using piezosurgery were reviewed and classified based on the adjacent teeth resistances shown in orthopantomogram (OPG) during their mesio-distal rotations: degree I refers to teeth with no adjacent teeth resistance; degree II refers to teeth with resistance released after mesial-half crown sectioning; degree III refers to teeth which still had resistance after mesial-half crown sectioning. With the use of surgical simulations using cone beam computerized tomography (CBCT) reconstruction, all teeth in degree I were designed to rotate mesio-distally; 86.36%(38/44) teeth in degree II were designed to rotate mesio-distally after mesio-half crown sectioning; 69.09%(36/55) teeth in degree III were designed to rotate bucco-lingually. All teeth were extracted successfully, and only one adjacent tooth was subluxated due to the incomplete bone removal. Our study suggested that in order to prevent adjacent teeth trauma, complete bone removal is of importance, and impacted teeth with higher adjacent teeth trauma risks should consider bucco-lingual rotations. PMID:27974819

  12. Adjacent tooth trauma in complicated mandibular third molar surgery: Risk degree classification and digital surgical simulation.

    Science.gov (United States)

    Ye, Zhou-Xi; Yang, Chi; Ge, Jing

    2016-12-15

    Analysis of adjacent tooth resistance is essential in wisdom teeth extraction to prevent adjacent tooth trauma, however it lacks adequate attention nowadays. This study aims at suggesting special extraction methods based on adjacent tooth resistance analysis for prevention of adjacent tooth damage. In this study, 136 complicated mandibular third molars extracted using piezosurgery were reviewed and classified based on the adjacent teeth resistances shown in orthopantomogram (OPG) during their mesio-distal rotations: degree I refers to teeth with no adjacent teeth resistance; degree II refers to teeth with resistance released after mesial-half crown sectioning; degree III refers to teeth which still had resistance after mesial-half crown sectioning. With the use of surgical simulations using cone beam computerized tomography (CBCT) reconstruction, all teeth in degree I were designed to rotate mesio-distally; 86.36%(38/44) teeth in degree II were designed to rotate mesio-distally after mesio-half crown sectioning; 69.09%(36/55) teeth in degree III were designed to rotate bucco-lingually. All teeth were extracted successfully, and only one adjacent tooth was subluxated due to the incomplete bone removal. Our study suggested that in order to prevent adjacent teeth trauma, complete bone removal is of importance, and impacted teeth with higher adjacent teeth trauma risks should consider bucco-lingual rotations.

  13. KAMG: A Tool for Converting Blood Ties and Affinity Ties into Adjacency Matrices

    Directory of Open Access Journals (Sweden)

    Hang Xiong

    2016-07-01

    Full Text Available Kinship Adjacency Matrix Generator (KAMG is a browser-based software for creating adjacency matrices using the information of kinship ties. Specifically, it is capable of converting the family trees in the format of GEDCOM files into adjacency matrices of blood relationship. With the data of intermarriages between different families, it can further create the adjacency matrix of affinity relationship for the families. The outcomes can be directly used to create networks. KAMG is written in JavaScript and implemented on web browsers. It is completely open source and the source code is publicly available on GitHub.

  14. Mangroves as a major source of soil carbon storage in adjacent seagrass meadows

    Science.gov (United States)

    Chen, Guangcheng; Azkab, Muhammad Husni; Chmura, Gail L.; Chen, Shunyang; Sastrosuwondo, Pramudji; Ma, Zhiyuan; Dharmawan, I. Wayan Eka; Yin, Xijie; Chen, Bin

    2017-01-01

    Mangrove forests have the potential to export carbon to adjacent ecosystems but whether mangrove-derived organic carbon (OC) would enhance the soil OC storage in seagrass meadows adjacent to mangroves is unclear. In this study we examine the potential for the contribution of mangrove OC to seagrass soils on the coast of North Sulawesi, Indonesia. We found that seagrass meadows adjacent to mangroves had significantly higher soil OC concentrations, soil OC with lower δ 13C, and lower bulk density than those at the non-mangrove adjacent meadows. Soil OC storage to 30 cm depth ranged from 3.21 to 6.82 kg C m−2, and was also significantly higher at the mangrove adjacent meadows than those non-adjacent meadows. δ13C analyses revealed that mangrove OC contributed 34 to 83% to soil OC at the mangrove adjacent meadows. The δ13C value of seagrass plants was also different between the seagrasses adjacent to mangroves and those which were not, with lower values measured at the seagrasses adjacent to mangroves. Moreover, we found significant spatial variation in both soil OC concentration and storage, with values decreasing toward sea, and the contribution of mangrove-derived carbon also reduced with distance from the forest. PMID:28186151

  15. Binary colloidal crystals

    NARCIS (Netherlands)

    Christova-Zdravkova, C.G.

    2005-01-01

    Binary crystals are crystals composed of two types of particles having different properties like size, mass density, charge etc. In this thesis several new approaches to make binary crystals of colloidal particles that differ in size, material and charge are reported We found a variety of crystal st

  16. Using crystal zoning to track crystal mush differentiation (Invited)

    Science.gov (United States)

    Humphreys, M.

    2010-12-01

    Exposed plutonic rocks contain clues to the differentiation and fractionation processes that may be operating beneath currently active volcanoes. There is potential to gain insights into phenomena including crystal fractionation, the movement of evolved fluids within a porous crystal mush, the extraction of late-stage melts, and the formation of precious metal deposits. In layered intrusions, attention has commonly focused on bulk magma differentiation, with the differentiation of interstitial liquids remaining in the mush being relatively neglected. However, μm-scale study of minor element zonation in intercumulus overgrowths and interstitial phases can help to understand the intricacies of crystal mush processes. By studying very slowly diffusing elements or components (such as TiO2 or anorthite content) it is possible to essentially eliminate problems relating to diffusive equilibration during prolonged slow cooling, and infer the evolving composition of the residual liquid. For layered intrusions, insights into crystal mush differentiation mechanisms can be obtained by comparing interstitial zoning profiles with the cryptic chemical changes that are observed in primocrysts with increasing stratigraphic height. The Skaergaard Intrusion, east Greenland, formed from essentially a single pulse of magma that solidified by near-perfect fractional crystallisation. The anorthite content (XAn) of the plagioclase primocrysts decreases monotonically with increasing stratigraphic height, as a result of crystallisation at lower temperatures and from increasingly evolved liquids. Ti contents of plagioclase increase systematically with stratigraphic height until cumulus Fe-Ti oxides appear, and then decrease as a result of falling liquid TiO2. However, interstitial Ti zoning follows different trends, which demonstrates that the interstitial and bulk liquids undergo very different liquid lines of descent. Distinct compositional trends develop adjacent to fine-grained, mafic

  17. Mixed crystal organic scintillators

    Science.gov (United States)

    Zaitseva, Natalia P; Carman, M Leslie; Glenn, Andrew M; Hamel, Sebastien; Hatarik, Robert; Payne, Stephen A; Stoeffl, Wolfgang

    2014-09-16

    A mixed organic crystal according to one embodiment includes a single mixed crystal having two compounds with different bandgap energies, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source, wherein the signal response signature does not include a significantly-delayed luminescence characteristic of neutrons interacting with the organic crystal relative to a luminescence characteristic of gamma rays interacting with the organic crystal. According to one embodiment, an organic crystal includes bibenzyl and stilbene or a stilbene derivative, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source.

  18. Pressure cryocooling protein crystals

    Science.gov (United States)

    Kim, Chae Un; Gruner, Sol M.

    2011-10-04

    Preparation of cryocooled protein crystal is provided by use of helium pressurizing and cryocooling to obtain cryocooled protein crystal allowing collection of high resolution data and by heavier noble gas (krypton or xenon) binding followed by helium pressurizing and cryocooling to obtain cryocooled protein crystal for collection of high resolution data and SAD phasing simultaneously. The helium pressurizing is carried out on crystal coated to prevent dehydration or on crystal grown in aqueous solution in a capillary.

  19. Crystal structure of 2-phenyl-ethanaminium 3-carb-oxy-prop-2-enoate.

    Science.gov (United States)

    Sowmya, N Swarna; Sampathkrishnan, S; Akilan, R; Chakkaravarthi, G; Kumar, R Mohan

    2015-09-01

    The title mol-ecular salt, C8H12N(+)·C4H3O4 (-), crystallized with two independent cations and anions in the asymmetric unit. The ethanaminium side chains of the cations exhibit anti conformations [C-C-C-N torsion angles = 176.5 (3) and -179.4 (3)°]. In the crystal, N-H⋯O and C-H⋯O hydrogen bonds connect adjacent anions and cations, and , O-H⋯O hydrogen bonds connect adjacent anions, generating sheets parallel to (001).

  20. Crystal structure of natural phaeosphaeride A

    Directory of Open Access Journals (Sweden)

    Victoria V. Abzianidze

    2015-08-01

    Full Text Available The asymmetric unit of the title compound, C15H23NO5, contains two independent molecules. Phaeosphaeride A contains two primary sections, an alkyl chain consisting of five C atoms and a cyclic system consisting of fused five- and six-membered rings with attached substituents. In the crystal, the molecules form layered structures. Nearly planar sheets, parallel to the (001 plane, form bilayers of two-dimensional hydrogen-bonded networks with the hydroxy groups located on the interior of the bilayer sheets. The network is constructed primarily of four O—H...O hydrogen bonds, which form a zigzag pattern in the (001 plane. The butyl chains interdigitate with the butyl chains on adjacent sheets. The crystal was twinned by a twofold rotation about the c axis, with refined major–minor occupancy fractions of 0.718 (6:0.282 (6.

  1. Fluorides leaching from restorative materials and the effect on adjacent teeth

    DEFF Research Database (Denmark)

    Qvist, Vibeke; Poulsen, Agneta; Teglers, Poul Thorpen

    2010-01-01

    Placing a Class II restoration in a tooth changes the local environment, including that for the adjacent tooth. Apart from the change to a less- or non-cariogenic environment for the restored tooth, the effect of leachable components from a restoration in the adjacent tooth should be taken into c...

  2. Are Caribbean mangroves important feeding grounds for juvenile reef fish from adjacent seagrass beds?

    NARCIS (Netherlands)

    Nagelkerken, I.A.; Velde, G. van der

    2004-01-01

    Little evidence is available on how juvenile fishes utilise seagrass beds and adjacent mangroves as feeding habitats. In this study we tested the degree to which Caribbean mangroves are utilised as feeding grounds by the fish community from adjacent seagrass beds. Stable carbon and nitrogen isotope

  3. 33 CFR 162.215 - Lake Tahoe, Nev.; restricted area adjacent to Nevada Beach.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Lake Tahoe, Nev.; restricted area adjacent to Nevada Beach. 162.215 Section 162.215 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... § 162.215 Lake Tahoe, Nev.; restricted area adjacent to Nevada Beach. (a) The restricted area....

  4. Are Caribbean mangroves important feeding grounds for juvenile reef fish from adjacent seagrass beds?

    NARCIS (Netherlands)

    Nagelkerken, I.A.; Velde, G. van der

    2004-01-01

    Little evidence is available on how juvenile fishes utilise seagrass beds and adjacent mangroves as feeding habitats. In this study we tested the degree to which Caribbean mangroves are utilised as feeding grounds by the fish community from adjacent seagrass beds. Stable carbon and nitrogen isotope

  5. 33 CFR 334.1060 - Oakland Outer Harbor adjacent to the Oakland Army Base; restricted area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Oakland Outer Harbor adjacent to the Oakland Army Base; restricted area. 334.1060 Section 334.1060 Navigation and Navigable Waters... REGULATIONS § 334.1060 Oakland Outer Harbor adjacent to the Oakland Army Base; restricted area. (a) The...

  6. Variable length adjacent partitioning for PTS based PAPR reduction of OFDM signal

    Energy Technology Data Exchange (ETDEWEB)

    Ibraheem, Zeyid T.; Rahman, Md. Mijanur; Yaakob, S. N.; Razalli, Mohammad Shahrazel; Kadhim, Rasim A. [School of Computer and Communication Engineering, Universiti Malaysia Perlis, 02600 Arau, Perlis (Malaysia)

    2015-05-15

    Peak-to-Average power ratio (PAPR) is a major drawback in OFDM communication. It leads the power amplifier into nonlinear region operation resulting into loss of data integrity. As such, there is a strong motivation to find techniques to reduce PAPR. Partial Transmit Sequence (PTS) is an attractive scheme for this purpose. Judicious partitioning the OFDM data frame into disjoint subsets is a pivotal component of any PTS scheme. Out of the existing partitioning techniques, adjacent partitioning is characterized by an attractive trade-off between cost and performance. With an aim of determining effects of length variability of adjacent partitions, we performed an investigation into the performances of a variable length adjacent partitioning (VL-AP) and fixed length adjacent partitioning in comparison with other partitioning schemes such as pseudorandom partitioning. Simulation results with different modulation and partitioning scenarios showed that fixed length adjacent partition had better performance compared to variable length adjacent partitioning. As expected, simulation results showed a slightly better performance of pseudorandom partitioning technique compared to fixed and variable adjacent partitioning schemes. However, as the pseudorandom technique incurs high computational complexities, adjacent partitioning schemes were still seen as favorable candidates for PAPR reduction.

  7. Treatment Outcome and Patient Satisfaction with Two Adjacent Implant-Supported Restorations in the Esthetic Zone

    NARCIS (Netherlands)

    Tymstra, Nynke; Meijer, Henny J. A.; Stellingsma, Kees; Raghoebar, Gerry M.; Vissink, Arjan

    2010-01-01

    The purpose of this study was to evaluate the clinical and radiographic parameters as well as the esthetic outcome of two adjacent implant-supported restorations and the surrounding peri-implant mucosa in the maxillary esthetic zone. Ten patients were treated with two adjacent implants in the anteri

  8. Assessment of heavy metal levels in surface sediments of estuaries and adjacent coastal areas in China

    Science.gov (United States)

    Liu, Xianbin; Li, Deliang; Song, Guisheng

    2017-03-01

    This article investigates the variations of contamination levels of heavy metals such as copper, lead, chromium, cadmium, zinc, arsenic, and mercury over time in surface sediments of the Changjiang River Estuary (CRE), Yellow River Estuary (YRE), Pearl River Estuary (PRE), and their adjacent coastal areas in China. The contamination factor (CF), pollution load index (PLI), and geoaccumulation index ( I geo) are used to evaluate the quality of the surface sediments in the study areas. The results showed that the CRE, YRE, and their adjacent coastal areas were at a low risk of contamination in terms of heavy metals, while the PRE and its adjacent coastal area were at a moderate level. By comparison, the concentrations of heavy metals in the surface sediments of the YRE and its adjacent coastal area were relatively lower than those in the CRE, PRE, and their adjacent coastal areas.

  9. CRYSTALLIZATION IN MULTICOMPONENT GLASSES

    Energy Technology Data Exchange (ETDEWEB)

    KRUGER AA; HRMA PR

    2009-10-08

    In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.

  10. Diaqua-bis-[bis-(pyrazin-2-yl) sulfide-κN (4)]bis-(thio-cyanato-κN)iron(II) monohydrate

    National Research Council Canada - National Science Library

    Wöhlert, Susanne; Jess, Inke; Näther, Christian

    2013-01-01

    ...) sulfide ligands and two water mol-ecules in an slightly distorted octa-hedral geometry. The Fe(II) cation is located on a center of inversion and the lattice water mol-ecule on a twofold rotation axis...

  11. Crystal structure of trans-1,4-bis-[(tri-methyl-sil-yl)-oxy]cyclo-hexa-2,5-diene-1,4-dicarbo-nitrile.

    Science.gov (United States)

    Glöcklhofer, Florian; Fröhlich, Johannes; Stöger, Berthold; Weil, Matthias

    2014-08-01

    The asymmetric unit of the title compound, C14H22N2O2Si2, contains one half of the mol-ecule, which is completed by inversion symmetry. The cyclo-hexa-2,5-diene ring is exactly planar and reflects the bond-length distribution of a pair of located double bonds [1.3224 (14) Å] and two pairs of single bonds [1.5121 (13) and 1.5073 (14) Å]. The tetra-hedral angle between the sp (3)-C atom and the two neighbouring sp (2)-C atoms in the cyclo-hexa-2,5-diene ring is enlarged by about 3°.

  12. System and method for forming synthetic protein crystals to determine the conformational structure by crystallography

    Science.gov (United States)

    Craig, George D.; Glass, Robert; Rupp, Bernhard

    1997-01-01

    A method for forming synthetic crystals of proteins in a carrier fluid by use of the dipole moments of protein macromolecules that self-align in the Helmholtz layer adjacent to an electrode. The voltage gradients of such layers easily exceed 10.sup.6 V/m. The synthetic protein crystals are subjected to x-ray crystallography to determine the conformational structure of the protein involved.

  13. Influence of Freeze-Thaw Cycles on RNA Integrity of Gastrointestinal Cancer and Matched Adjacent Tissues.

    Science.gov (United States)

    Hu, Ying; Han, Haibo; Wang, Yixue; Song, Lijie; Cheng, Xiaojing; Xing, Xiaofang; Dong, Bin; Wang, Xiaohong; Chen, Meng; Zhang, Lianhai; Ji, Jiafu

    2017-06-01

    Comparative analysis of RNA expression profiles between cancer and adjacent noncancerous tissues is an important part of cancer research. High-quality RNA is essential for consistent, reliable results, especially for identification of cancer biomarkers. However, the impact of freeze-thaw cycles on the quality of RNA both in gastrointestinal cancer and paired adjacent tissues is still unclear. To investigate the influence of freeze-thaw cycles on RNA integrity and overall histomorphology of gastrointestinal cancer and paired adjacent noncancerous tissues. Gastrointestinal cancer and matched adjacent noncancerous tissues were frozen and thawed twice before extracting RNA. Total RNA in each sample was extracted with TRIzol reagents and the RNA integrity was assessed by RNA integrity number (RIN) on an Agilent Bioanalyzer. Light microscopy was then used to assess tissue composition and morphology. RIN values for all samples tended to decrease in correlation with the frequency of freeze-thawing. With an RIN cutoff value of 6, RNA extracted from pancreatic cancer tissues was not qualified after the first freeze-thaw cycle. Moreover, all RNA extracted from adjacent noncancerous tissues had nonqualifying RIN scores after the first freeze-thaw cycle, except for liver tissues. Microscopically, all samples displayed qualified tissue morphology regardless of freeze-thaw cycle frequency. Freeze-thawing affects the RNA integrity, but not the tissue morphology of gastrointestinal cancer and paired adjacent noncancerous tissues. Furthermore, the RNA extracted from adjacent noncancerous tissues is more easily degraded than that in cancer tissues.

  14. Crystal structure and prediction.

    Science.gov (United States)

    Thakur, Tejender S; Dubey, Ritesh; Desiraju, Gautam R

    2015-04-01

    The notion of structure is central to the subject of chemistry. This review traces the development of the idea of crystal structure since the time when a crystal structure could be determined from a three-dimensional diffraction pattern and assesses the feasibility of computationally predicting an unknown crystal structure of a given molecule. Crystal structure prediction is of considerable fundamental and applied importance, and its successful execution is by no means a solved problem. The ease of crystal structure determination today has resulted in the availability of large numbers of crystal structures of higher-energy polymorphs and pseudopolymorphs. These structural libraries lead to the concept of a crystal structure landscape. A crystal structure of a compound may accordingly be taken as a data point in such a landscape.

  15. Growth of dopamine crystals

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Vidya, E-mail: vidya.patil@ruparel.edu; Patki, Mugdha, E-mail: mugdha.patki@ruparel.edu [D. G. Ruparel College, Senapati Bapat Marg, Mahim, Mumbai – 400 016 (India)

    2016-05-06

    Many nonlinear optical (NLO) crystals have been identified as potential candidates in optical and electro-optical devices. Use of NLO organic crystals is expected in photonic applications. Hence organic nonlinear optical materials have been intensely investigated due to their potentially high nonlinearities, and rapid response in electro-optic effect compared to inorganic NLO materials. There are many methods to grow organic crystals such as vapor growth method, melt growth method and solution growth method. Out of these methods, solution growth method is useful in providing constraint free crystal. Single crystals of Dopamine have been grown by evaporating the solvents from aqueous solution. Crystals obtained were of the size of orders of mm. The crystal structure of dopamine was determined using XRD technique. Images of crystals were obtained using FEG SEM Quanta Series under high vacuum and low KV.

  16. Growth of dopamine crystals

    Science.gov (United States)

    Patil, Vidya; Patki, Mugdha

    2016-05-01

    Many nonlinear optical (NLO) crystals have been identified as potential candidates in optical and electro-optical devices. Use of NLO organic crystals is expected in photonic applications. Hence organic nonlinear optical materials have been intensely investigated due to their potentially high nonlinearities, and rapid response in electro-optic effect compared to inorganic NLO materials. There are many methods to grow organic crystals such as vapor growth method, melt growth method and solution growth method. Out of these methods, solution growth method is useful in providing constraint free crystal. Single crystals of Dopamine have been grown by evaporating the solvents from aqueous solution. Crystals obtained were of the size of orders of mm. The crystal structure of dopamine was determined using XRD technique. Images of crystals were obtained using FEG SEM Quanta Series under high vacuum and low KV.

  17. Adjacency Preserving Bijection Maps of Hermitian Matrices over any Division Ring with an Involution

    Institute of Scientific and Technical Information of China (English)

    Li Ping HUANG

    2007-01-01

    Let D be any division ring with an involution, H(D) be the space of all n × n hermitian matrices over D. Two hermitian matrices A and B are said to be adjacent if rank(A - B) =1. It is proved that if ψ is a bijective map from H(D)(n ≥ 2) to itself such that ψ preserves the adjacency,then ψ-1 also preserves the adjacency. Moreover, if H(D)≠F3(F2), then ψ preserves the arithmetic distance. Thus, an open problem posed by Wan Zhe-Xian is answered for geometry of symmetric and hermitian matrices.

  18. ALICE photon spectrometer crystals

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    Members of the mechanical assembly team insert the last few crystals into the first module of ALICE's photon spectrometer. These crystals are made from lead-tungstate, a crystal as clear as glass but with nearly four times the density. When a high-energy particle passes through one of these crystals it will scintillate, emitting a flash of light allowing the energy of photons, electrons and positrons to be measured.

  19. Crystallization from Gels

    Science.gov (United States)

    Narayana Kalkura, S.; Natarajan, Subramanian

    Among the various crystallization techniques, crystallization in gels has found wide applications in the fields of biomineralization and macromolecular crystallization in addition to crystallizing materials having nonlinear optical, ferroelectric, ferromagnetic, and other properties. Furthermore, by using this method it is possible to grow single crystals with very high perfection that are difficult to grow by other techniques. The gel method of crystallization provides an ideal technique to study crystal deposition diseases, which could lead to better understanding of their etiology. This chapter focuses on crystallization in gels of compounds that are responsible for crystal deposition diseases. The introduction is followed by a description of the various gels used, the mechanism of gelling, and the fascinating phenomenon of Liesegang ring formation, along with various gel growth techniques. The importance and scope of study on crystal deposition diseases and the need for crystal growth experiments using gel media are stressed. The various crystal deposition diseases, viz. (1) urolithiasis, (2) gout or arthritis, (3) cholelithiasis and atherosclerosis, and (4) pancreatitis and details regarding the constituents of the crystal deposits responsible for the pathological mineralization are discussed. Brief accounts of the theories of the formation of urinary stones and gallstones and the role of trace elements in urinary stone formation are also given. The crystallization in gels of (1) the urinary stone constituents, viz. calcium oxalate, calcium phosphates, uric acid, cystine, etc., (2) the constituents of the gallstones, viz. cholesterol, calcium carbonate, etc., (3) the major constituent of the pancreatic calculi, viz., calcium carbonate, and (4) cholic acid, a steroidal hormone are presented. The effect of various organic and inorganic ions, trace elements, and extracts from cereals, herbs, and fruits on the crystallization of major urinary stone and gallstone

  20. CRYSTAL FILTER TEST SET

    Science.gov (United States)

    CRYSTAL FILTERS, *HIGH FREQUENCY, *RADIOFREQUENCY FILTERS, AMPLIFIERS, ELECTRIC POTENTIAL, FREQUENCY, IMPEDANCE MATCHING , INSTRUMENTATION, RADIOFREQUENCY, RADIOFREQUENCY AMPLIFIERS, TEST EQUIPMENT, TEST METHODS

  1. Artistic Crystal Creations

    Science.gov (United States)

    Lange, Catherine

    2008-01-01

    In this inquiry-based, integrative art and science activity, Grade 5-8 students use multicolored Epsom salt (magnesium sulfate) crystallizing solutions to reveal beautiful, cylindrical, 3-dimensional, needle-shaped structures. Through observations of the crystal art, students analyze factors that contribute to crystal size and formation, compare…

  2. Protein Crystal Based Nanomaterials

    Science.gov (United States)

    Bell, Jeffrey A.; VanRoey, Patrick

    2001-01-01

    This is the final report on a NASA Grant. It concerns a description of work done, which includes: (1) Protein crystals cross-linked to form fibers; (2) Engineering of protein to favor crystallization; (3) Better knowledge-based potentials for protein-protein contacts; (4) Simulation of protein crystallization.

  3. Analysis of liquid crystal properties for photonic crystal fiber devices

    DEFF Research Database (Denmark)

    Weirich, Johannes; Lægsgaard, Jesper; Wei, Lei

    2009-01-01

    We analyze the bandgap structure of Liquid Crystal infiltrated Photonic Crystal Fibers depending on the parameters of the Liquid Crystals by means of finite element simulations. For a biased Liquid Crystal Photonic Crystal Fiber, we show how the tunability of the bandgap position depends...... on the Liquid Crystal parameters....

  4. Crystal structures of the all-cysteinyl-coordinated D14C variant of Pyrococcus furiosus ferredoxin: [4Fe–4S] ↔ [3Fe–4S] cluster conversion

    DEFF Research Database (Denmark)

    Løvgreen, Monika Nøhr; Martic, Maja; Windahl, Michael S.

    2011-01-01

    molecules have different crystal packing and intramolecular disulfide bond conformation. The crystal packing reveals a β-sheet interaction between A molecules in adjacent asymmetric units, whereas B molecules are packed as monomers in a less rigid position next to the A–A extended β-sheet dimers...

  5. Interactions of salicylic acid derivatives with calcite crystals.

    Science.gov (United States)

    Ukrainczyk, Marko; Gredičak, Matija; Jerić, Ivanka; Kralj, Damir

    2012-01-01

    Investigation of basic interactions between the active pharmaceutical compounds and calcium carbonates is of great importance because of the possibility to use the carbonates as a mineral carrier in drug delivery systems. In this study the mode and extent of interactions of salicylic acid and its amino acid derivates, chosen as pharmaceutically relevant model compounds, with calcite crystals are described. Therefore, the crystal growth kinetics of well defined rhombohedral calcite seed crystals in the systems containing salicylic acid (SA), 5-amino salicylic acid (5-ASA), N-salicyloil-l-aspartic acid (N-Sal-Asp) or N-salicyloil-l-glutamic acid (N-Sal-Glu), were investigated. The precipitation systems were of relatively low initial supersaturation and of apparently neutral pH. The data on the crystal growth rate reductions in the presence of the applied salicylate molecules were analyzed by means of Cabrera & Vermileya's, and Kubota & Mullin's models of interactions of the dissolved additives and crystal surfaces. The crystal growth kinetic experiments were additionally supported with the appropriate electrokinetic, spectroscopic and adsorption measurements. The Langmuir adsorption constants were determined and they were found to be in a good correlation with values obtained from crystal growth kinetic analyses. The results indicated that salicylate molecules preferentially adsorb along the steps on the growing calcite surfaces. The values of average spacing between the adjacent salicylate adsorption active sites and the average distance between the neighboring adsorbed salicylate molecules were also estimated.

  6. Correspondence Associated with the Agreement for Road Improvement Adjacent to Tewaukon National Widlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document contains correspondence associated with the cooperative agreement for the construction of a road bridge and approaches adjacent to the Tewaukon...

  7. Correspondence Associated with the Agreement for Drainage on Lands Adjacent to Tewaukon National Widlife

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document contains correspondence associated with the cooperative agreement for drainage on lands adjacent to the Tewaukon National Wildlife Refuge. This...

  8. TP53 mutations in clinically normal mucosa adjacent to oral carcinomas

    DEFF Research Database (Denmark)

    Thode, Christenze; Bilde, Anders; von Buchwald, Christian;

    2010-01-01

    products were separated by denatured gradient gel electrophoresis. Fragments with a deviant DGEE pattern were sequenced. RESULTS: TP53 mutations were found in six of 18 tumours. Fourteen specimens contained histologically normal mucosa adjacent to the tumour; 13 of these showed small clusters of p53...... positive cells. Seven specimens contained both histological normal and dysplastic epithelial tissues adjacent to the tumour. A TP53 mutation was found in only one specimen; this mutation appeared in the normal mucosa, the adjacent tumour, and the epithelial dysplasia. CONCLUSION: We found that upregulation...... of p53 was a frequent event in histological normal mucosa adjacent to OSCC; however, it was rarely associated with a mutation in the TP53 gene....

  9. Cooperative Agreement for Road Improvement Adjacent to Tewaukon National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This cooperative agreement concerns the construction of a road bridge and approaches adjacent to the Tewaukon National Wildlife Refuge. This agreement is between the...

  10. Prophylactic vertebroplasty can decrease the fracture risk of adjacent vertebrae: an in vitro cadaveric study

    NARCIS (Netherlands)

    Aquarius, R.; Homminga, J.; Hosman, A.J.F.; Verdonschot, N.J.; Tanck, E.J.

    2014-01-01

    Adjacent level vertebral fractures are common in patients with osteoporotic wedge fractures, but can theoretically be prevented with prophylactic vertebroplasty. Previous tests on prophylactic vertebroplasties have been performed under axial loading, while in vivo changes in spinal alignment likely

  11. Prophylactic vertebroplasty can decrease the fracture risk of adjacent vertebrae: An in vitro cadaveric study

    NARCIS (Netherlands)

    Aquarius, R.; Homminga, J.J.; Hosman, A.J.F.; Verdonschot, N.J.J.; Tanck, E.

    2014-01-01

    Adjacent level vertebral fractures are common in patients with osteoporotic wedge fractures, but can theoretically be prevented with prophylactic vertebroplasty. Previous tests on prophylactic vertebroplasties have been performed under axial loading, while in vivo changes in spinal alignment likely

  12. Rock samples and geochemical analyses of Afghanistan and adjacent areas (rockafg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile contains points that describe the location of rock samples (core samples and outcrop samples) collected in Afghanistan and adjacent areas, and the...

  13. Oil samples and geochemical analyses of Afghanistan and adjacent areas (oilafg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile contains points that describe the location of oil samples collected in Afghanistan and adjacent areas, and the results of organic geochemical analysis.

  14. Study of deer movement on and adjacent to Fort Niobrara National Wildlife Refuge final report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We evaluated movements and home ranges of white-tailed deer (WT) and mule deer (MD) on and adjacent to Fort Niobrara National Wildlife Refuge (NWR) in north-central...

  15. Protein crystallization with paper

    Science.gov (United States)

    Matsuoka, Miki; Kakinouchi, Keisuke; Adachi, Hiroaki; Maruyama, Mihoko; Sugiyama, Shigeru; Sano, Satoshi; Yoshikawa, Hiroshi Y.; Takahashi, Yoshinori; Yoshimura, Masashi; Matsumura, Hiroyoshi; Murakami, Satoshi; Inoue, Tsuyoshi; Mori, Yusuke; Takano, Kazufumi

    2016-05-01

    We developed a new protein crystallization method that incorporates paper. A small piece of paper, such as facial tissue or KimWipes, was added to a drop of protein solution in the traditional sitting drop vapor diffusion technique, and protein crystals grew by incorporating paper. By this method, we achieved the growth of protein crystals with reducing osmotic shock. Because the technique is very simple and the materials are easy to obtain, this method will come into wide use for protein crystallization. In the future, it could be applied to nanoliter-scale crystallization screening on a paper sheet such as in inkjet printing.

  16. Effects of unisegmental disc compression on adjacent segments: an in vivo animal model.

    Science.gov (United States)

    Unglaub, Frank; Guehring, Thorsten; Lorenz, Helga; Carstens, Claus; Kroeber, Markus W

    2005-12-01

    It is controversial whether fusion of discs in the spine leads to increased degeneration on the remaining discs or whether the degenerative changes are merely a part of the inevitable natural history process. To determine the effects of unisegmental compression and subsequent recovery on adjacent segments, we studied histology, radiology and intradiscal pressure using an in vivo rabbit model. Fifteen New Zealand rabbits were divided in to three groups of five. In the first group, the intervertebral disc L4-L5 of the lumbar spine was axially loaded for 28 days with an external loading device. In the second group, the intervertebral disc was compressed for 28 days and allowed to recover for an equal amount of time, with the loading device removed. Five animals underwent a sham operation, in which the external loading device was situated, but their discs remained unloaded for 28 days. The intradiscal pressure was determined in the loaded discs as well as in the cranial and caudal adjacent discs. Lateral radiographs were taken from each subjected intervertebral disc with adjacent vertebral bodies and the cranial and caudal adjacent segments. The compressed discs showed lower intradiscal pressure in comparison with the control group, which remained unloaded. In the cranial and caudal discs adjacent to the loaded discs the average intradiscal pressure was similar to the unloaded controls. The loaded discs demonstrated a significant decrease in disc space. No discs adjacent to the loaded discs changed in height. The lamellar architecture of the inner, middle, and outer annulus became more disorganized in the loaded discs. The nucleus pulposus showed increase of mucoid degeneration and increased cell death. Intervertebral discs from the control group and the adjacent discs to the compressed discs maintained their normal morphology. This study shows that mechanical loading of discs in the spine can cause rapid degeneration. Adjacent discs, however, did not change in terms

  17. Risk Factors for the Development of Adjacent Segment Disease Following Anterior Cervical Arthrodesis

    OpenAIRE

    Ezgi Akar; Mehmet Ufuk Akmil; Merih İş

    2015-01-01

    Aim: The aim of this study was to clinically and radiologically evaluate the efficacy of anterior cervical discectomy and fusion (ACDF) in the treatment of adjacent level degeneration. Methods: We retrospectively evaluated 89 patients (55 females, 34 males) who underwent ACDF. Adjacent segment degeneration findings were evaluated by investigating new osteophyte formation, growth of existing osteophytes, ossification of the anterior longitudinal ligament, presence of inter...

  18. Correlation between sagittal plane changes and adjacent segment degeneration following lumbar spine fusion

    OpenAIRE

    Kumar, Malhar; Baklanov, Andrei; Chopin, Daniel

    2001-01-01

    Adjacent segment degeneration following lumbar spine fusion remains a widely acknowledged problem, but there is insufficient knowledge regarding the factors that contribute to its occurrence. The aim of this study is to analyse the relationship between abnormal sagittal plane configuration of the lumbar spine and the development of adjacent segment degeneration. Eighty-three consecutive patients who underwent lumbar fusion for degenerative disc disease were reviewed retrospectively. Patients ...

  19. Minimally invasive treatment for esthetic enhancement of white spot lesion in adjacent tooth.

    Science.gov (United States)

    Lee, Ji-Hye; Kim, Dae-Gon; Park, Chan-Jin; Cho, Lee-Ra

    2013-08-01

    This article describes the treatment provided to a patient with the maxillary anterior teeth exhibiting severe secondary caries beneath the previous restoration and a white spot lesion on the adjacent incisor. Two implants were placed after extraction of hopeless teeth with the guided bone regeneration technique. A white spot lesion of the adjacent incisor was treated with minimally invasive treatment. This clinical report describes the multidisciplinary treatment for the white spot lesion and esthetic restoration of missing anterior teeth.

  20. Crystal structure of methyl (2R,3S-3-[(tert-butylsulfinylamino]-2-fluoro-3-phenylpropanoate

    Directory of Open Access Journals (Sweden)

    Zhiwei Zhao

    2015-12-01

    Full Text Available The title compound, C14H20FNO3S, contains two chiral carbon centres and the absolute configuration has been confirmed as (2R,3S. In the crystal, adjacent molecules are linked by weak C—H...O hydrogen bonds, generating zigzag chains along the a-axis direction.

  1. Integrated optical components based on planar photonic crystal waveguides with perturbed border holes

    DEFF Research Database (Denmark)

    Niemi, Tapio; Frandsen, Lars Hagedorn; Harpøth, Anders;

    2005-01-01

    In this work, we have experimentally and by simulations investigated the effect of making small perturbations of the size of the border holes adjacent to the planar photonic crystal waveguide (PCW). The waveguide is created by removing one row of holes in the nearest-neighbour direction of air ho...

  2. catena-Poly[[[(dimethyl-malonato-κO:O')(perchlorato-κO)copper(II)]-μ-bis-(3-pyridylmeth-yl)piperazinediium-κN:N] perchlorate dihydrate].

    Science.gov (United States)

    Farnum, Gregory A; Laduca, Robert L

    2008-11-13

    In the title compound, {[Cu(C(5)H(6)O(4))(ClO(4))(C(16)H(22)N(4))]ClO(4)·2H(2)O}(n), square-pyramidally coordinated Cu atoms with perchlorate and dimethyl-malonate ligands are connected into cationic sinusoidal coordination polymer chains by doubly protonated bis-(3-pyridylmeth-yl)piperazine (3-bpmp) ligands. The chains aggregate into pseudo-layers parallel to the (101) crystal planes by N-H⋯O hydrogen bonding. Unligated perchlorate anions and water mol-ecules of crystallization provide additional hydrogen bonding between pseudo-layers.

  3. Ethyl 2-amino-4-(3-chloro-phen-yl)-5,10-dioxo-5,10-dihydro-4H-benzo[g]chromene-3-carboxyl-ate.

    Science.gov (United States)

    Hu, Xiao; Lei, Song; Yao, Chang-Sheng

    2009-05-20

    The title mol-ecule, C(22)H(16)ClNO(5), was obtained by the reaction of (E)-ethyl 3-(3-chloro-phen-yl)-2-cyano-acrylate and 2-hydroxy-naphthalene-1,4-dione catalysed by triethylamine in ethanol. In the crystal structure, the chlorobenzene ring makes a dihedral angle of 88.63 (4)° with the fused ring system. The six-membered ring formed by an intra-molecular N-H⋯O hydrogen bond is almost planar. The crystal packing is stabilized by N-H⋯O hydrogen bonds.

  4. {4,4',6,6'-Tetra-chloro-2,2'-[2,2-dimethyl-propane-1,3-diylbis(nitrilo-methanylyl-idene)]}copper(II).

    Science.gov (United States)

    Kargar, Hadi; Kia, Reza; Abbasian, Saeideh; Tahir, Muhammad Nawaz

    2012-02-01

    In the title Schiff base complex, [Cu(C(19)H(16)Cl(4)N(2)O(2))], the geometry around the Cu(II) atom is distorted square-planar defined by the N(2)O(2) donor atoms of the coordinated ligand. The dihedral angle between the substituted benzene rings is 29.95 (16)°. In the crystal, mol-ecules are linked along the b axis, forming individual dimers through C-H⋯O inter-actions. The crystal structure is further stabilized by inter-molecular π-π inter-actions [centroid-centroid distance = 3.6131 (17) Å].

  5. cis-Aquabis(2,2'-bipyridine-κ2N,N')-fluoridochromium(III) bis(perchlorate) dihydrate

    DEFF Research Database (Denmark)

    Birk, Torben; Bendix, Jesper

    2010-01-01

    The title mixed aqua-fluoride complex, [CrF(C(10)H(8)N(2))(2)(H(2)O)](ClO(4))(2)·2H(2)O, has been synthesized by aqua-tion of the corresponding difluoride complex using lanthan-ide(III) ions as F(-) acceptors. The complex crystallizes with a Cr(III) ion at the center of a distorted octa......-hedral coordination polyhedron with a cis arrangement of ligands. The crystal packing shows a hydrogen-bonding pattern involving water mol-ecules, the coordinated F atom and the perchlorate anions....

  6. Ethyl 6-methyl-4-[2-(4,4,5,5-tetra-methyl-1,3,2-dioxaborolan-2-yl)thio-phen-3-yl]-2-thioxo-1,2,3,4-tetra-hydro-pyrimidine-5-carboxyl-ate.

    Science.gov (United States)

    Decken, Andreas; Zamora, Matthew T; Duguay, Dominique R; Vogels, Christopher M; Westcott, Stephen A

    2008-04-26

    A new Biginelli compound, C(18)H(25)BN(2)O(4)S(2), containing a boronate ester group was synthesized from a lithium bromide-catalysed reaction. The compound crystallizes with two independent mol-ecules in the asymmetric unit that differ mainly in the conformation of the ester functionality. The crystal structure is stabilized by inter-molecular N-H⋯O and N-H⋯S hydrogen bonds involving the 3,4-dihydro-pyrimidine-2(1H)-thione NH groups as donors and the carbonyl O and thio-phene S atoms as acceptors.

  7. 3-Acetyl-1-(2,4-dimethyl-phen-yl)thio-urea.

    Science.gov (United States)

    Gowda, B Thimme; Foro, Sabine; Kumar, Sharatha

    2012-08-01

    In the crystal structure of the title compound, C(11)H(14)N(2)OS, the two N-H bonds are anti to each other. There is an intramolecular N-H⋯O hydrogen bond generating an S(6) ring motif.In the crystal, mol-ecules are linked via N-H⋯S hydrogen bonds with an R(2) (2)(8) motif and N-H⋯O hydrogen bonds with an R(2) (2)(12) motif into chains running along [1-10].

  8. Analysis of CD83 antigen expression in human breast fibroadenoma and adjacent tissue

    Directory of Open Access Journals (Sweden)

    Marcus Nascimento Borges

    Full Text Available CONTEXT AND OBJECTIVE: Dendritic cell maturation is considered essential for starting an immune response. The CD83 antigen is an important marker of dendritic cell maturation. The objectives here were to analyze CD83 antigen expression in human breast fibroadenoma and breast tissue adjacent to the lesion and to identify clinical factors that might influence this expression. DESIGN AND SETTING: This was a retrospective study at a public university hospital, in which 29 histopathological samples of breast fibroadenoma and adjacent breast tissue, from 28 women of reproductive age, were analyzed. METHODS: The immunohistochemistry method was used to analyze the cell expression of the antigen. The antigen expression in the cells was evaluated by means of random manual counting using an optical microscope. RESULTS: Positive expression of the CD83 antigen in the epithelial cells of the fibroadenoma (365.52; standard deviation ± 133.13 in relation to the adjacent breast tissue cells (189.59; standard deviation ± 140.75 was statistically larger (P < 0.001. Several clinical features were analyzed, but only parity was shown to influence CD83 antigen expression in the adjacent breast tissue, such that positive expression was more evident in nulliparous women (P = 0.042. CONCLUSIONS: The expression of the CD83 antigen in the fibroadenoma was positive and greater than in the adjacent breast tissue. Positive expression of the antigen in the adjacent breast tissue was influenced by parity, and was significantly more evident in nulliparous women.

  9. Risk Factors for the Development of Adjacent Segment Disease Following Anterior Cervical Arthrodesis

    Directory of Open Access Journals (Sweden)

    Ezgi Akar

    2015-06-01

    Full Text Available Aim: The aim of this study was to clinically and radiologically evaluate the efficacy of anterior cervical discectomy and fusion (ACDF in the treatment of adjacent level degeneration. Methods: We retrospectively evaluated 89 patients (55 females, 34 males who underwent ACDF. Adjacent segment degeneration findings were evaluated by investigating new osteophyte formation, growth of existing osteophytes, ossification of the anterior longitudinal ligament, presence of intervertebral disc space narrowing, sagittal alignment and range of motion (ROM using serial radiographs and magnetic resonance imaging. Results: The mean age of the 89 patients was 41.3 (24-76 years. The mean follow-up duration was 34.3 (12-64 months. Radiographic evidence of adjacent segment degeneration was observed in 12 patients (13.4%. Nine (75% patients had new complaints. Of the patients who had degenerative changes, 7 were (58% were male, 5 (42% were female; the mean age was 46 (30- 62 years. It was observed that the level of fusion and the number of fusion did not increase the adjacent segment degeneration. All of 12 patients were observed to have a non lordotic cervical spine and increased ROM. Conclusion: Development of degeneration at the level adjacent to region anterior cervical discectomy and fusion performed is higher compared to non-adjacent levels. The level of fusion and the number of fusion levels have no effect on the development of degeneration. (The Medical Bulletin of Haseki 2015; 53:120-3

  10. Macromolecular Crystallization in Microgravity

    Science.gov (United States)

    Snell, Edward H.; Helliwell, John R.

    2004-01-01

    The key concepts that attracted crystal growers, macromolecular or solid state, to microgravity research is that density difference fluid flows and sedimentation of the growing crystals are greatly reduced. Thus, defects and flaws in the crystals can be reduced, even eliminated, and crystal volume can be increased. Macromolecular crystallography differs from the field of crystalline semiconductors. For the latter, crystals are harnessed for their electrical behaviors. A crystal of a biological macromolecule is used instead for diffraction experiments (X-ray or neutron) to determine the three-dimensional structure of the macromolecule. The better the internal order of the crystal of a biological macromolecule then the more molecular structure detail that can be extracted. This structural information that enables an understanding of how the molecule functions. This knowledge is changing the biological and chemical sciences with major potential in understanding disease pathologies. Macromolecular structural crystallography in general is a remarkable field where physics, biology, chemistry, and mathematics meet to enable insight to the basic fundamentals of life. In this review, we examine the use of microgravity as an environment to grow macromolecular crystals. We describe the crystallization procedures used on the ground, how the resulting crystals are studied and the knowledge obtained from those crystals. We address the features desired in an ordered crystal and the techniques used to evaluate those features in detail. We then introduce the microgravity environment, the techniques to access that environment, and the theory and evidence behind the use of microgravity for crystallization experiments. We describe how ground-based laboratory techniques have been adapted to microgravity flights and look at some of the methods used to analyze the resulting data. Several case studies illustrate the physical crystal quality improvements and the macromolecular structural

  11. Polymer semiconductor crystals

    Directory of Open Access Journals (Sweden)

    Jung Ah Lim

    2010-05-01

    Full Text Available One of the long-standing challenges in the field of polymer semiconductors is to figure out how long interpenetrating and entangled polymer chains self-assemble into single crystals from the solution phase or melt. The ability to produce these crystalline solids has fascinated scientists from a broad range of backgrounds including physicists, chemists, and engineers. Scientists are still on the hunt for determining the mechanism of crystallization in these information-rich materials. Understanding the theory and concept of crystallization of polymer semiconductors will undoubtedly transform this area from an art to an area that will host a bandwagon of scientists and engineers. In this article we describe the basic concept of crystallization and highlight some of the advances in polymer crystallization from crystals to nanocrystalline fibers.

  12. CMS lead tungstate crystals

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    These crystals are made from lead tungstate, a crystal that is as clear as glass yet with nearly four times the density. They have been produced in Russia to be used as scintillators in the electromagnetic calorimeter on the CMS experiment, part of the LHC project at CERN. When an electron, positron or photon passes through the calorimeter it will cause a cascade of particles that will then be absorbed by these scintillating crystals, allowing the particle's energy to be measured.

  13. Macromolecular crystallization in microgravity

    Energy Technology Data Exchange (ETDEWEB)

    Snell, Edward H [Biophysics Group, NASA Marshall Space Flight Center, Code XD42, Huntsville, AL 35812 (United States); Helliwell, John R [Department of Chemistry, The University of Manchester, Manchester, M13 9PL (United Kingdom)

    2005-04-01

    Density difference fluid flows and sedimentation of growing crystals are greatly reduced when crystallization takes place in a reduced gravity environment. In the case of macromolecular crystallography a crystal of a biological macromolecule is used for diffraction experiments (x-ray or neutron) so as to determine the three-dimensional structure of the macromolecule. The better the internal order of the crystal then the greater the molecular structure detail that can be extracted. It is this structural information that enables an understanding of how the molecule functions. This knowledge is changing the biological and chemical sciences, with major potential in understanding disease pathologies. In this review, we examine the use of microgravity as an environment to grow macromolecular crystals. We describe the crystallization procedures used on the ground, how the resulting crystals are studied and the knowledge obtained from those crystals. We address the features desired in an ordered crystal and the techniques used to evaluate those features in detail. We then introduce the microgravity environment, the techniques to access that environment and the theory and evidence behind the use of microgravity for crystallization experiments. We describe how ground-based laboratory techniques have been adapted to microgravity flights and look at some of the methods used to analyse the resulting data. Several case studies illustrate the physical crystal quality improvements and the macromolecular structural advances. Finally, limitations and alternatives to microgravity and future directions for this research are covered. Macromolecular structural crystallography in general is a remarkable field where physics, biology, chemistry and mathematics meet to enable insight to the fundamentals of life. As the reader will see, there is a great deal of physics involved when the microgravity environment is applied to crystallization, some of it known, and undoubtedly much yet to

  14. Analysis of liquid crystal properties for photonic crystal fiber devices

    DEFF Research Database (Denmark)

    Weirich, Johannes; Lægsgaard, Jesper; Wei, Lei;

    2009-01-01

    We analyze the bandgap structure of Liquid Crystal infiltrated Photonic Crystal Fibers depending on the parameters of the Liquid Crystals by means of finite element simulations. For a biased Liquid Crystal Photonic Crystal Fiber, we show how the tunability of the bandgap position depends on the L...

  15. The relative influence of road characteristics and habitat on adjacent lizard populations in arid shrublands

    Science.gov (United States)

    Hubbard, Kaylan A.; Chalfoun, Anna D.; Gerow, Kenneth G.

    2016-01-01

    As road networks continue to expand globally, indirect impacts to adjacent wildlife populations remain largely unknown. Simultaneously, reptile populations are declining worldwide and anthropogenic habitat loss and fragmentation are frequently cited causes. We evaluated the relative influence of three different road characteristics (surface treatment, width, and traffic volume) and habitat features on adjacent populations of Northern Sagebrush Lizards (Sceloporus graciosus graciosus), Plateau Fence Lizards (S. tristichus), and Greater Short-Horned Lizards (Phrynosoma hernandesi) in mixed arid shrubland habitats in southwest Wyoming. Neither odds of lizard presence nor relative abundance was significantly related to any of the assessed road characteristics, although there was a trend for higher Sceloporus spp. abundance adjacent to paved roads. Sceloporus spp. relative abundance did not vary systematically with distance to the nearest road. Rather, both Sceloporus spp. and Greater Short-Horned Lizards were associated strongly with particular habitat characteristics adjacent to roads. Sceloporus spp. presence and relative abundance increased with rock cover, relative abundance was associated positively with shrub cover, and presence was associated negatively with grass cover. Greater Short-Horned Lizard presence increased with bare ground and decreased marginally with shrub cover. Our results suggest that habitat attributes are stronger correlates of lizard presence and relative abundance than individual characteristics of adjacent roads, at least in our system. Therefore, an effective conservation approach for these species may be to consider the landscape through which new roads and their associated development would occur, and the impact that placement could have on fragment size and key habitat elements.

  16. Uplink scheduling and adjacent-channel coupling loss analysis for TD-LTE deployment.

    Science.gov (United States)

    Yeo, Woon-Young; Moon, Sung Ho; Kim, Jae-Hoon

    2014-01-01

    TD-LTE, one of the two duplexing modes in LTE, operates in unpaired spectrum and has the advantages of TDD-based technologies. It is expected that TD-LTE will be more rapidly deployed in near future and most of WiMax operators will upgrade their networks to TD-LTE gradually. Before completely upgrading to TD-LTE, WiMax may coexist with TD-LTE in an adjacent frequency band. In addition, multiple TD-LTE operators may deploy their networks in adjacent bands. When more than one TDD network operates in adjacent frequency bands, severe interference may happen due to adjacent channel interference (ACI) and unsynchronized operations. In this paper, coexistence issues between TD-LTE and other systems are analyzed and coexistence requirements are provided. This paper has three research objectives. First, frame synchronization between TD-LTE and WiMax is discussed by investigating possible combinations of TD-LTE and WiMax configurations. Second, an uplink scheduling algorithm is proposed to utilize a leakage pattern of ACI in synchronized operations. Third, minimum requirements for coexistence in unsynchronized operations are analyzed by introducing a concept of adjacent-channel coupling loss. From the analysis and simulation results, we can see that coexistence of TD-LTE with other TDD systems is feasible if the two networks are synchronized. For the unsynchronized case, some special cell-site engineering techniques may be required to reduce the ACI.

  17. Identification of protein-RNA interaction sites using the information of spatial adjacent residues

    Directory of Open Access Journals (Sweden)

    Cheng Yong-Mei

    2011-10-01

    Full Text Available Abstract Background Protein-RNA interactions play an important role in numbers of fundamental cellular processes such as RNA splicing, transport and translation, protein synthesis and certain RNA-mediated enzymatic processes. The more knowledge of Protein-RNA recognition can not only help to understand the regulatory mechanism, the site-directed mutagenesis and regulation of RNA–protein complexes in biological systems, but also have a vitally effecting for rational drug design. Results Based on the information of spatial adjacent residues, novel feature extraction methods were proposed to predict protein-RNA interaction sites with SVM-KNN classifier. The total accuracies of spatial adjacent residue profile feature and spatial adjacent residues weighted accessibility solvent area feature are 78%, 67.07% respectively in 5-fold cross-validation test, which are 1.4%, 3.79% higher than that of sequence neighbour residue profile feature and sequence neighbour residue accessibility solvent area feature. Conclusions The results indicate that the performance of feature extraction method using the spatial adjacent information is superior to the sequence neighbour information approach. The performance of SVM-KNN classifier is little better than that of SVM. The feature extraction method of spatial adjacent information with SVM-KNN is very effective for identifying protein-RNA interaction sites and may at least play a complimentary role to the existing methods.

  18. Uplink Scheduling and Adjacent-Channel Coupling Loss Analysis for TD-LTE Deployment

    Directory of Open Access Journals (Sweden)

    Woon-Young Yeo

    2014-01-01

    Full Text Available TD-LTE, one of the two duplexing modes in LTE, operates in unpaired spectrum and has the advantages of TDD-based technologies. It is expected that TD-LTE will be more rapidly deployed in near future and most of WiMax operators will upgrade their networks to TD-LTE gradually. Before completely upgrading to TD-LTE, WiMax may coexist with TD-LTE in an adjacent frequency band. In addition, multiple TD-LTE operators may deploy their networks in adjacent bands. When more than one TDD network operates in adjacent frequency bands, severe interference may happen due to adjacent channel interference (ACI and unsynchronized operations. In this paper, coexistence issues between TD-LTE and other systems are analyzed and coexistence requirements are provided. This paper has three research objectives. First, frame synchronization between TD-LTE and WiMax is discussed by investigating possible combinations of TD-LTE and WiMax configurations. Second, an uplink scheduling algorithm is proposed to utilize a leakage pattern of ACI in synchronized operations. Third, minimum requirements for coexistence in unsynchronized operations are analyzed by introducing a concept of adjacent-channel coupling loss. From the analysis and simulation results, we can see that coexistence of TD-LTE with other TDD systems is feasible if the two networks are synchronized. For the unsynchronized case, some special cell-site engineering techniques may be required to reduce the ACI.

  19. Gas explosion in a room with a window and passage to an adjacent room

    Directory of Open Access Journals (Sweden)

    Polandov Yuri

    2016-01-01

    Full Text Available Some publications describe an effect, produced during a physical model experiment, when an adjacent gas-free room influences the gas explosion pressure in a room with a window. The explosion pressure in this case significantly exceeds (2.5 times the explosion pressure in a room without an adjacent room. This result has been confirmed by our studies. Based on other available information about the influence of the ignition point location on the explosion pressure in one room, it was suggested that this could be true for an explosion in two rooms. In our studies we used a test unit with two connected chambers, each having a volume of 1.125 m3. It turned out that this influence of the adjacent volume was not so unambiguous as it was described in those publications. It was found out that the maximum effect of explosion pressure amplification by the adjacent room is achieved, when the igniter is located in the chamber filled with a gas-air mixture in the area between the center of the chamber and the window (maximum amplification by more than 3 times. This effect is lower directly by the window (1.8 times and is practically absent in case of ignition within the area near the passage connecting the chamber with the adjacent room. This suggests that the effect discovered earlier is a special case of the general dependence of the gas explosion pressure in two chambers on the igniter location.

  20. Non-target adjacent stimuli classification improves performance of classical ERP-based brain computer interface

    Science.gov (United States)

    Ceballos, G. A.; Hernández, L. F.

    2015-04-01

    Objective. The classical ERP-based speller, or P300 Speller, is one of the most commonly used paradigms in the field of Brain Computer Interfaces (BCI). Several alterations to the visual stimuli presentation system have been developed to avoid unfavorable effects elicited by adjacent stimuli. However, there has been little, if any, regard to useful information contained in responses to adjacent stimuli about spatial location of target symbols. This paper aims to demonstrate that combining the classification of non-target adjacent stimuli with standard classification (target versus non-target) significantly improves classical ERP-based speller efficiency. Approach. Four SWLDA classifiers were trained and combined with the standard classifier: the lower row, upper row, right column and left column classifiers. This new feature extraction procedure and the classification method were carried out on three open databases: the UAM P300 database (Universidad Autonoma Metropolitana, Mexico), BCI competition II (dataset IIb) and BCI competition III (dataset II). Main results. The inclusion of the classification of non-target adjacent stimuli improves target classification in the classical row/column paradigm. A gain in mean single trial classification of 9.6% and an overall improvement of 25% in simulated spelling speed was achieved. Significance. We have provided further evidence that the ERPs produced by adjacent stimuli present discriminable features, which could provide additional information about the spatial location of intended symbols. This work promotes the searching of information on the peripheral stimulation responses to improve the performance of emerging visual ERP-based spellers.

  1. Phononic crystal devices

    Science.gov (United States)

    El-Kady, Ihab F.; Olsson, Roy H.

    2012-01-10

    Phononic crystals that have the ability to modify and control the thermal black body phonon distribution and the phonon component of heat transport in a solid. In particular, the thermal conductivity and heat capacity can be modified by altering the phonon density of states in a phononic crystal. The present invention is directed to phononic crystal devices and materials such as radio frequency (RF) tags powered from ambient heat, dielectrics with extremely low thermal conductivity, thermoelectric materials with a higher ratio of electrical-to-thermal conductivity, materials with phononically engineered heat capacity, phononic crystal waveguides that enable accelerated cooling, and a variety of low temperature application devices.

  2. Heroin crystal nephropathy.

    Science.gov (United States)

    Bautista, Josef Edrik Keith; Merhi, Basma; Gregory, Oliver; Hu, Susie; Henriksen, Kammi; Gohh, Reginald

    2015-06-01

    In this paper we present an interesting case of acute kidney injury and severe metabolic alkalosis in a patient with a history of heavy heroin abuse. Urine microscopy showed numerous broomstick-like crystals. These crystals are also identified in light and electron microscopy. We hypothesize that heroin crystalizes in an alkaline pH, resulting in tubular obstruction and acute kidney injury. Management is mainly supportive as there is no known specific therapy for this condition. This paper highlights the utility of urine microscopy in diagnosing the etiology of acute kidney injury and proposes a novel disease called heroin crystal nephropathy.

  3. Geometric and unipotent crystals

    OpenAIRE

    Berenstein, Arkady; Kazhdan, David

    1999-01-01

    In this paper we introduce geometric crystals and unipotent crystals which are algebro-geometric analogues of Kashiwara's crystal bases. Given a reductive group G, let I be the set of vertices of the Dynkin diagram of G and T be the maximal torus of G. The structure of a geometric G-crystal on an algebraic variety X consists of a rational morphism \\gamma:X-->T and a compatible family e_i:G_m\\times X-->X, i\\in I of rational actions of the multiplicative group G_m satisfying certain braid-like ...

  4. Automation in biological crystallization

    Science.gov (United States)

    Shaw Stewart, Patrick; Mueller-Dieckmann, Jochen

    2014-01-01

    Crystallization remains the bottleneck in the crystallographic process leading from a gene to a three-dimensional model of the encoded protein or RNA. Automation of the individual steps of a crystallization experiment, from the preparation of crystallization cocktails for initial or optimization screens to the imaging of the experiments, has been the response to address this issue. Today, large high-throughput crystallization facilities, many of them open to the general user community, are capable of setting up thousands of crystallization trials per day. It is thus possible to test multiple constructs of each target for their ability to form crystals on a production-line basis. This has improved success rates and made crystallization much more convenient. High-throughput crystallization, however, cannot relieve users of the task of producing samples of high quality. Moreover, the time gained from eliminating manual preparations must now be invested in the careful evaluation of the increased number of experiments. The latter requires a sophisticated data and laboratory information-management system. A review of the current state of automation at the individual steps of crystallization with specific attention to the automation of optimization is given. PMID:24915074

  5. Tunable plasmonic crystal

    Science.gov (United States)

    Dyer, Gregory Conrad; Shaner, Eric A.; Reno, John L.; Aizin, Gregory

    2015-08-11

    A tunable plasmonic crystal comprises several periods in a two-dimensional electron or hole gas plasmonic medium that is both extremely subwavelength (.about..lamda./100) and tunable through the application of voltages to metal electrodes. Tuning of the plasmonic crystal band edges can be realized in materials such as semiconductors and graphene to actively control the plasmonic crystal dispersion in the terahertz and infrared spectral regions. The tunable plasmonic crystal provides a useful degree of freedom for applications in slow light devices, voltage-tunable waveguides, filters, ultra-sensitive direct and heterodyne THz detectors, and THz oscillators.

  6. Automation in biological crystallization.

    Science.gov (United States)

    Stewart, Patrick Shaw; Mueller-Dieckmann, Jochen

    2014-06-01

    Crystallization remains the bottleneck in the crystallographic process leading from a gene to a three-dimensional model of the encoded protein or RNA. Automation of the individual steps of a crystallization experiment, from the preparation of crystallization cocktails for initial or optimization screens to the imaging of the experiments, has been the response to address this issue. Today, large high-throughput crystallization facilities, many of them open to the general user community, are capable of setting up thousands of crystallization trials per day. It is thus possible to test multiple constructs of each target for their ability to form crystals on a production-line basis. This has improved success rates and made crystallization much more convenient. High-throughput crystallization, however, cannot relieve users of the task of producing samples of high quality. Moreover, the time gained from eliminating manual preparations must now be invested in the careful evaluation of the increased number of experiments. The latter requires a sophisticated data and laboratory information-management system. A review of the current state of automation at the individual steps of crystallization with specific attention to the automation of optimization is given.

  7. Crystallization Formulation Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The Crystallization Formulation Lab fills a critical need in the process development and optimization of current and new explosives and energetic formulations. The...

  8. Tunable plasmonic crystal

    Energy Technology Data Exchange (ETDEWEB)

    Dyer, Gregory Conrad; Shaner, Eric A.; Reno, John L.; Aizin, Gregory

    2015-08-11

    A tunable plasmonic crystal comprises several periods in a two-dimensional electron or hole gas plasmonic medium that is both extremely subwavelength (.about..lamda./100) and tunable through the application of voltages to metal electrodes. Tuning of the plasmonic crystal band edges can be realized in materials such as semiconductors and graphene to actively control the plasmonic crystal dispersion in the terahertz and infrared spectral regions. The tunable plasmonic crystal provides a useful degree of freedom for applications in slow light devices, voltage-tunable waveguides, filters, ultra-sensitive direct and heterodyne THz detectors, and THz oscillators.

  9. A crystal barrel

    CERN Multimedia

    2007-01-01

    The production of crystals for the barrel of the CMS electromagnetic calorimeter has been completed. This is an important milestone for the experiment, which received the last of its 62,960 crystals on 9 March. The members of the team responsible for the crystal acceptance testing at CERN display the last crystal for the CMS electromagnetic calorimeter barrel. From left to right: Igor Tarasov, Etiennette Auffray and Hervé Cornet.One of the six machines specially developed to measure 67 different parameters on each crystal. Igor Tarasov is seen inserting the last batch of crystals into the machine. The last of the 62,960 CMS barrel crystals arrived at CERN on 9 March. Once removed from its polystyrene protection, this delicate crystal, like thousands of its predecessors, will be inserted into the last of the 36 supermodules of the barrel electromagnetic calorimeter in a few days' time. This marks the end of an important chapter in an almost 15-year-long journey by the CMS crystals team, some of whose member...

  10. Advanced Protein Crystallization Facility (APCF)

    Science.gov (United States)

    1998-01-01

    This section of the Life and Microgravity Spacelab (LMS) publication contains articles entitled: (1) Crystallization of EGFR-EGF; (2) Crystallization of Apocrustacyanin C1; (3) Crystallization and X-ray Analysis of 5S rRNA and the 5S rRNA Domain A; (4) Growth of Lysozyme Crystals at Low Nucleation Density; (5) Comparative Analysis of Aspartyl tRNA-synthetase and Thaumatin Crystals Grown on Earth and In Microgravity; (6) Lysosome Crystal Growth in the Advanced Protein Crystallization Facility Monitored via Mach-Zehnder Interferometry and CCD Video; (7) Analysis of Thaumatin Crystals Grown on Earth and in Microgravity; (8) Crystallization of the Nucleosome Core Particle; (9) Crystallization of Photosystem I; (10) Mechanism of Membrane Protein Crystal Growth: Bacteriorhodopsin-mixed Micelle Packing at the Consolution Boundary, Stabilized in Microgravity; (11) Crystallization in a Microgravity Environment of CcdB, a Protein Involved in the Control of Cell Death; and (12) Crystallization of Sulfolobus Solfataricus

  11. Depth distribution of Moho and tectonic framework in eastern Asian continent and its adjacent ocean areas

    Institute of Scientific and Technical Information of China (English)

    TENG; Jiwen; (滕吉文); ZENG; Rongsheng; (曾融生); YAN; Yafen; (闫雅芬); ZHANG; Hui; (张慧)

    2003-01-01

    With the results of interpretation of seismic sounding profiles acquired in the past 30 years in the continent of China and its adjacent countries andocean regions, such as Russia, Kazakhstan, Japan, India, Pakistan, Philippine ocean basin, Pacific and Indian Ocean, we compiled a 2D Moho distribution map forthe continent and its adjacent areas of eastern Asia. From the features of depth distribution and undulation of Moho, it is suggested that the eastern Asian region can be divided into 18 gradient belts with different sizes, 18 crustal blocks, 20 sediment basins and depression zones. The depth of Moho varies smoothly in each block, while the boundary (separating different blocks) delineates the abrupt variation of Moho depth. Then, some subjects,such as oregen and sediment basin, fault system and rift, plate boundary, ocean-continent coupling and tectonic framework, are discussed based on the distribution gradient belts and block partition features of Moho depth in the eastern Asia and its adjacent regions.

  12. Benign Lesions in Mucosa Adjacent to Intestinal-Type Sinonasal Adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Blanca Vivanco

    2011-01-01

    Full Text Available Occupational exposure to wood dust is a strong risk factor for the development of intestinal-type sinonasal adenocarcinoma (ITAC; however, knowledge on possible precursor lesions or biomarkers is limited. Fifty-one samples of tumor-adjacent mucosa and 19 control samples of mucosa from the unaffected fossa of ITAC patients were evaluated for histological changes and p53 protein expression. Mild dysplasia was observed in 14%, cuboidal metaplasia in 57%, intestinal metaplasia in 8%, squamous metaplasia in 24%, and cylindrocellular hyperplasia in 53% of cases. P53 immunopositivity was generally weak occurring most frequently in squamous metaplasia. Wood dust etiology did not appear of influence on the histological changes, but p53 showed a tendency for higher positivity. Dysplasia adjacent to tumor was indicative of subsequent development of recurrence. In conclusion, precursor lesions do occur in mucosa adjacent to ITAC. This is clinically important, because it may justify the screening of high-risk individuals such as woodworkers.

  13. Seismic Waves Scattering Impact through Tunnel Excavation on Adjacent Monuments Subjected to Far Field Earthquakes

    Directory of Open Access Journals (Sweden)

    Ghobakhloo E.

    2015-09-01

    Full Text Available The study of the effect of seismic wave scattering has attracted extensive attention in the past couple of decades especially in infrastructures like tunnels. A seismic wave, meeting the tunnel, can generate scattering which, in most cases, may incur damages in adjacent structures. In this study, using Finite Element Method (FEM, the effect of seismic wave scattering in far field has been investigated. The twin tunnels of Shiraz subway system are selected as the case study in this research and three far field seismic waves were chosen for time history analyses. Investigating the normal mode (before tunnel construction in comparison to the excavation mode (after tunnel construction enables calculation of the effect of displacement in adjacent structures. The analysis results indicate there is a significant difference between before and after tunnel construction (P-value<0.05. Accordingly, the influence of constructing a tunnel on adjacent surface structures is very important for tunnel design.

  14. Dosimetric study of field junction in adjacent beams using asymmetric collimators and MLC

    Institute of Scientific and Technical Information of China (English)

    Ahmed Zaki; Hosnya Abu-Zeid; Hada Ashry; Khaled EL Shahat

    2014-01-01

    Adjacent treatment fields are commonly employed in external beam radiation therapy, such as the mantle and inverted-Y fields for the treatment of Hodgkin’s disease. In some cases, the adjacent fields are orthogonal, such as the cra-niospinal fields used in the treatment of meduloblastoma. Another example is the irradiation of head and neck tumors when the lateral neck fields are placed adjacent to the anterior supraclavicular field. In each of these situations, there is a possibility of introducing very large dosage errors across the junction. Consequently, this region is at risk for tumor recurrence if it is underdosed or severe complications if it is overdosed. Four milimeter overlap and gap resulted in an unacceptable dose in homogeneity in the junction. As a result of this study, the magnitudes of hot and cold spots might be clinicaly acceptable for 3 mm gap between photon fields.

  15. Small vulvar squamous cell carcinomas and adjacent tissues. A morphologic study

    DEFF Research Database (Denmark)

    Poulsen, Hemming; Junge, Jette; Vyberg, Mogens;

    2003-01-01

    Vulvar squamous cell carcinomas are of different subtypes and degrees of differentiation, and may be associated with adjacent lichen sclerosus and/or varying degrees of dysplasia. The aim of this investigation was to study small carcinomas with a diameter of less than 2 cm in order to find...... a possible relation between subtypes of carcinomas and adjacent epithelial changes. Fourteen cases of small vulvar squamous cell carcinomas were totally embedded in paraffin. Serial sectioning made a detailed mapping of all different lesions possible, and a two- and three-dimensional imaging was obtained...... in each case. Seven patients with keratinizing squamous cell carcinomas (median age 65) had adjacent lichen sclerosus. All carcinomas were completely surrounded by areas of VIN1. VIN2 and VIN3 were not found. Seven patients without lichen sclerosus (median age 58) showed squamous cell carcinomas...

  16. Crystal structure of 4-methylsulfanyl-2-phenylquinazoline

    Directory of Open Access Journals (Sweden)

    Mohammed B. Alshammari

    2014-08-01

    Full Text Available In the title compound, C15H12N2S, the methylthioquinazoline group is planar with the methyl C displaced by only 0.116 (3 Å from the plane of the quinazoline moiety. The dihedral angle between the phenyl ring and the quinazoline ring system is 13.95 (5°. In the crystal, each molecule is linked by π–π stacking between to two adjacent inversion-related molecules. On one side, the inverted quinazoline groups interact with a centroid–centroid distance of 3.7105 (9 Å. On the other side, the quinazoline group interacts with the pyrimidine and phenyl rings of the second neighbour with centroid–centroid distances of 3.5287 (8 and 3.8601 (9 Å, respectively.

  17. Magnetic Field in Superlattices Semiconductors of Crystals

    Directory of Open Access Journals (Sweden)

    Luciano Nascimento

    2015-05-01

    Full Text Available In this work we present a study on the super-semiconductor networks, using the Kronig-Penney model for the effective mass approximation, and then the calculations for the application of the magnetic field perpendicular and parallel to the layers of super lattices crystals. The magnetic field applied parallel to the layers, was used to adjust the resonance of a higher energy subband of a well by thermal excitation with a lower energy subband of the adjacent well, increasing energy levels in its tunneling rate. We use the formalism of Schrödinger equation of quantum mechanics. Introducing the calculations in a systematic way in superlattices for each semiconductor quantum well to assess their energy spectrum systematically studied.

  18. Stock structure of Atlantic herring Clupea harengus in the Norwegian Sea and adjacent waters

    DEFF Research Database (Denmark)

    Pampoulie, Christophe; Slotte, Aril; Oskarsson, Guomundur J.;

    2015-01-01

    The genetic structure of Atlantic herring Clupea harengus L. was investigated in its north-easterly distribution in the Norwegian Sea and adjacent waters, using 23 neutral and one non-neutral (Cpa111) microsatellite loci. Fish from the suspected 2 main populations-the Norwegian spring-spawning he......The genetic structure of Atlantic herring Clupea harengus L. was investigated in its north-easterly distribution in the Norwegian Sea and adjacent waters, using 23 neutral and one non-neutral (Cpa111) microsatellite loci. Fish from the suspected 2 main populations-the Norwegian spring...

  19. Computation and analysis of the geomagnetic field model in China and its adjacent area for 2003

    Institute of Scientific and Technical Information of China (English)

    GU Zuo-wen; AN Zhen-chang; GAO Jin-tian; ZHAN Zhi-jia; YAO Tong-qi; HAN Wei; CHEN Bin

    2006-01-01

    Based on the geomagnetic data at 135 stations and 35 observatories in China in 2003, the Taylor polynomial model and the spherical cap harmonic model in China and its adjacent area for 2003 were established. In the model calculation, the truncation order of the model and the influences of the boundary restriction on the model calculation were carefully analyzed. The results show that the geomagnetic data used are precise and reliable, and the selection of the truncation order is reasonable. The Taylor polynomial model and the spherical cap harmonic model in China and its adjacent area established in this paper are consistent very well.

  20. Flow and transport within a coastal aquifer adjacent to a stratified water body

    Science.gov (United States)

    Oz, Imri; Yechieli, Yoseph; Eyal, Shalev; Gavrieli, Ittai; Gvirtzman, Haim

    2016-04-01

    The existence of a freshwater-saltwater interface and the circulation flow of saltwater beneath the interface is a well-known phenomenon found at coastal aquifers. This flow is a natural phenomenon that occurs due to density differences between fresh groundwater and the saltwater body. The goals of this research are to use analytical, numerical, and physical models in order to examine the configuration of the freshwater-saltwater interface and the density-driven flow patterns within a coastal aquifer adjacent to long-term stratified saltwater bodies (e.g. meromictic lake). Such hydrological systems are unique, as they consist of three different water types: the regional fresh groundwater, and low and high salinity brines forming the upper and lower water layers of the stratified water body, respectively. This research also aims to examine the influence of such stratification on hydrogeological processes within the coastal aquifer. The coastal aquifer adjacent to the Dead Sea, under its possible future meromictic conditions, serves as an ideal example to examine these processes. The results show that adjacent to a stratified saltwater body three interfaces between three different water bodies are formed, and that a complex flow system, controlled by the density differences, is created, where three circulation cells are developed. These results are significantly different from the classic circulation cell that is found adjacent to non-stratified water bodies (lakes or oceans). In order to obtain a more generalized insight into the groundwater behavior adjacent to a stratified water body, we used the numerical model to perform sensitivity analysis. The hydrological system was found be sensitive to three dimensionless parameters: dimensionless density (i.e. the relative density of the three water bodies'); dimensionless thickness (i.e. the ratio between the relative thickness of the upper layer and the whole thickness of the lake); and dimensionless flux. The results

  1. The adjacency matrix of one type of graph and the Fibonacci numbers

    CERN Document Server

    Yılmaz, Fatih; Bozkurt, Durmuş

    2012-01-01

    Recently there is huge interest in graph theory and intensive study on computing integer powers of matrices. In this paper, we investigate relationships between one type of graph and well-known Fibonacci sequence. In this content, we consider the adjacency matrix of one type of graph with 2k (k=1,2,...) vertices. It is also known that for any positive integer r, the (i,j)th entry of A^{r} (A is the adjacency matrix of the graph) is just the number of walks from vertex i to vertex j, that use exactly k edges.

  2. Effect of two nonfumigant nematicides on corn grown in two adjacent fields infested with different nematodes.

    Science.gov (United States)

    Dickson, D W; Hewlett, T E

    1987-10-01

    The organo-phosphate experimental nematicide, O-ethyl S,S-di-sec-butyl phosphorodithioate (FMC 67825), provided yield increases of corn comparable to carbofuran. Both the emulsifiable concentrate and granular formulations of FMC 67825 were equally effective. The evaluations, duplicated in two adjacent fields, clearly demonstrated the importance of the type of plant pathogenic nematodes infesting the sites. Where Belonolaimus longicaudatus occurred, yield increases ranged from 73% to 80%, whereas in the adjacent field (without B. longicaudatus) yields increases ranged from - 14% to 28%.

  3. Photonic crystal fibers

    DEFF Research Database (Denmark)

    Lægsgaard, Jesper; Hansen, K P; Nielsen, M D;

    2003-01-01

    Photonic crystal fibers having a complex microstructure in the transverse plane constitute a new and promising class of optical fibers. Such fibers can either guide light through total internal reflection or the photonic bandgap effect, In this paper, we review the different types and applications...... of photonic crystal fibers with particular emphasis on recent advances in the field....

  4. Demonstration of Crystal Structure.

    Science.gov (United States)

    Neville, Joseph P.

    1985-01-01

    Describes an experiment where equal parts of copper and aluminum are heated then cooled to show extremely large crystals. Suggestions are given for changing the orientation of crystals by varying cooling rates. Students are more receptive to concepts of microstructure after seeing this experiment. (DH)

  5. Walkout in Crystal City

    Science.gov (United States)

    Barrios, Greg

    2009-01-01

    When students take action, they create change that extends far beyond the classroom. In this article, the author, who was a former teacher from Crystal City, Texas, remembers the student walkout that helped launch the Latino civil rights movement 40 years ago. The Crystal City student walkout remains a high point in the history of student activism…

  6. Manipulation of colloidal crystallization

    NARCIS (Netherlands)

    Vermolen, E.C.M.

    2008-01-01

    Colloidal particles (approximately a micrometer in diameter) that are dispersed in a fluid, behave thermodynamically similar to atoms and molecules: at low concentrations they form a fluid, while at high concentrations they can crystallize into a colloidal crystal to gain entropy. The analogy with m

  7. Crystal growth and crystallography

    Science.gov (United States)

    Chernov, A. A.

    1998-01-01

    Selected topics that may be of interest for both crystal-structure and crystal-growth communities are overviewed. The growth of protein crystals, along with that of some other compounds, is one of the topics, and recent insights into related phenomena are considered as examples of applications of general principles. The relationship between crystal growth shape and structure is reviewed and an attempt to introduce semiquantitative characterization of binding for proteins is made. The concept of kinks for complex structures is briefly discussed. Even at sufficiently low supersaturations, the fluctuation of steps may not be sufficient to implement the Gibbs-Thomson law if the kink density is low enough. Subsurface ordering of liquids and growth of rough interfaces from melts is discussed. Crystals growing in microgravity from solution should be more perfect if they preferentially trap stress-inducing impurities, thus creating an impurity-depleted zone around themselves. Evidently, such a zone is developed only around the crystals growing in the absence of convection. Under terrestrial conditions, the self-purified depleted zone is destroyed by convection, the crystal traps more impurity and grows stressed. The stress relief causes mosaicity. In systems containing stress-inducing but poorly trapped impurities, the crystals grown in the absence of convection should be worse than those of their terrestrial counterparts.

  8. Crystals in the LHC

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    Bent crystals can be used to deflect charged particle beams. Their use in high-energy accelerators has been investigated for almost 40 years. Recently, a bent crystal was irradiated for the first time in the HiRadMat facility with an extreme particle flux, which crystals would have to withstand in the LHC. The results were very encouraging and confirmed that this technology could play a major role in increasing the beam collimation performance in future upgrades of the machine.   UA9 bent crystal tested with a laser. Charged particles interacting with a bent crystal can be trapped in channelling states and deflected by the atomic planes of the crystal lattice (see box). The use of bent crystals for beam manipulation in particle accelerators is a concept that has been well-assessed. Over the last three decades, a large number of experimental findings have contributed to furthering our knowledge and improving our ability to control crystal-particle interactions. In modern hadron colliders, su...

  9. Photonic Crystal Fiber Attenuator

    Institute of Scientific and Technical Information of China (English)

    Joo; Beom; Eom; Hokyung; Kim; Jinchae; Kim; Un-Chul; Paek; Byeong; Ha; Lee

    2003-01-01

    We propose a novel fiber attenuator based on photonic crystal fibers. The difference in the modal field diameters of a conventional single mode fiber and a photonic crystal fiber was used. A variable optical attenuator was also achieved by applying macro-bending on the PCF part of the proposed attenuator

  10. Active Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Ek, Sara

    This thesis deals with the fabrication and characterization of active photonic crystal waveguides, realized in III-V semiconductor material with embedded active layers. The platform offering active photonic crystal waveguides has many potential applications. One of these is a compact photonic...... crystal semiconductor optical amplier. As a step towards such a component, photonic crystal waveguides with a single quantum well, 10 quantum wells and three layers of quantum dots are fabricated and characterized. An experimental study of the amplied spontaneous emission and a implied transmission...... are presented in this thesis. A variation of photonic crystal design parameters are used leading to a spectral shift of the dispersion, it is veried that the observed effects shift accordingly. An enhancement of the amplified spontaneous emission was observed close to the band edge, where light is slowed down...

  11. Function Photonic Crystals

    CERN Document Server

    Wu, Xiang-Yao; Yang, Jing-Hai; Liu, Xiao-Jing; Ba, Nuo; Wu, Yi-Heng; Wang, Qing-Cai; Li, Jing-Wu

    2010-01-01

    In the paper, we present a new kind of function photonic crystals, which refractive index is a function of space position. Unlike conventional PCs, which structure grow from two materials, A and B, with different dielectric constants $\\epsilon_{A}$ and $\\epsilon_{B}$. By Fermat principle, we give the motion equations of light in one-dimensional, two-dimensional and three-dimensional function photonic crystals. For one-dimensional function photonic crystals, we study the dispersion relation, band gap structure and transmissivity, and compare them with conventional photonic crystals. By choosing various refractive index distribution function $n(z)$, we can obtain more width or more narrow band gap structure than conventional photonic crystals.

  12. Progress on photonic crystals

    CERN Document Server

    Lecoq, P; Gundacker, S; Hillemanns, H; Jarron, P; Knapitsch, A; Leclercq, J L; Letartre, X; Meyer, T; Pauwels, K; Powolny, F; Seassal, C

    2010-01-01

    The renewal of interest for Time of Flight Positron Emission Tomography (TOF PET) has highlighted the need for increasing the light output of scintillating crystals and in particular for improving the light extraction from materials with a high index of refraction. One possible solution to overcome the problem of total internal reflection and light losses resulting from multiple bouncing within the crystal is to improve the light extraction efficiency at the crystal/photodetector interface by means of photonic crystals, i.e. media with a periodic modulation of the dielectric constant at the wavelength scale. After a short reminder of the underlying principles this contribution proposes to present the very encouraging results we have recently obtained on LYSO pixels and the perspectives on other crystals such as BGO, LuYAP and LuAG. These results confirm the impressive predictions from our previously published Monte Carlo simulations. A detailed description of the sample preparation procedure is given as well ...

  13. Optically Anomalous Crystals

    CERN Document Server

    Shtukenberg, Alexander; Kahr, Bart

    2007-01-01

    Optical anomalies in crystals are puzzles that collectively constituted the greatest unsolved problems in crystallography in the 19th Century. The most common anomaly is a discrepancy between a crystal’s symmetry as determined by its shape or by X-ray analysis, and that determined by monitoring the polarization state of traversing light. These discrepancies were perceived as a great impediment to the development of the sciences of crystals on the basis of Curie’s Symmetry Principle, the grand organizing idea in the physical sciences to emerge in the latter half of the 19th Century. Optically Anomalous Crystals begins with an historical introduction covering the contributions of Brewster, Biot, Mallard, Brauns, Tamman, and many other distinguished crystallographers. From this follows a tutorial in crystal optics. Further chapters discuss the two main mechanisms of optical dissymmetry: 1. the piezo-optic effect, and 2. the kinetic ordering of atoms. The text then tackles complex, inhomogeneous crystals, and...

  14. Crystallization phenomena of isotactic polystyrene

    NARCIS (Netherlands)

    Lemstra, Peter Jan

    1975-01-01

    In this thesis the crystallization behavior of isotactic polystyrene has been described. The kinetics of the crystallization process and the crystalline structure were studied both for crystallization in the bulk and from dilute solutions. ... Zie Summary

  15. Shaped Crystal Growth

    Science.gov (United States)

    Tatartchenko, Vitali A.

    Crystals of specified shape and size (shaped crystals) with controlled crystal growth (SCG) defect and impurity structure have to be grown for the successful development of modern engineering. Since the 1950s many hundreds of papers and patents concerned with shaped growth have been published. In this chapter, we do not try to enumerate the successful applications of shaped growth to different materials but rather to carry out a fundamental physical and mathematical analysis of shaping as well as the peculiarities of shaped crystal structures. Four main techniques, based on which the lateral surface can be shaped without contact with the container walls, are analyzed: the Czochralski technique (CZT), the Verneuil technique (VT), the floating zone technique (FZT), and technique of pulling from shaper (TPS). Modifications of these techniques are analyzed as well. In all these techniques the shape of the melt meniscus is controlled by surface tension forces, i.e., capillary forces, and here they are classified as capillary shaping techniques (CST). We look for conditions under which the crystal growth process in each CST is dynamically stable. Only in this case are all perturbations attenuated and a crystal of constant cross section shaping technique (CST) grown without any special regulation. The dynamic stability theory of the crystal growth process for all CST is developed on the basis of Lyapunov's dynamic stability theory. Lyapunov's equations for the crystal growth processes follow from fundamental laws. The results of the theory allow the choice of stable regimes for crystal growth by all CST as well as special designs of shapers in TPS. SCG experiments by CZT, VT, and FZT are discussed but the main consideration is given to TPS. Shapers not only allow crystal of very complicated cross section to be grown but provide a special distribution of impurities. A history of TPS is provided later in the chapter, because it can only be described after explanation of the

  16. 8-Chloro-4-oxo-4H-chromene-3-carbaldehyde.

    Science.gov (United States)

    Ishikawa, Yoshinobu

    2014-07-01

    In the title compound, C10H5ClO3, a chlorinated 3-formyl-chromone derivative, all atoms are essentially coplanar (r.m.s. deviation = 0.032 Å for the non-H atoms), with the largest deviation from the least-squares plane [0.0598 (14) Å] being for a pyran-ring C atom. In the crystal, mol-ecules are linked through stacking inter-actions along the b axis [shortest centroid-centroid distance between the pyran and benzene rings = 3.566 (2) Å].

  17. 1-(4a,8-Dimethyl-1,2,3,4,4a,5,6,8a-octa-hydro-naphthalen-2-yl)-3-(4-methyl-phen-yl)prop-2-en-1-one.

    Science.gov (United States)

    Tebbaa, Mohamed; Benharref, Ahmed; Berraho, Moha; Avignant, Daniel; Oudahmane, Abdelghani; Akssira, Mohamed

    2011-06-01

    The title compound, C(22)H(28)O, was isolated from the aerial part of Inula viscosa- (L) Aiton [or Dittrichia viscosa- (L) Greuter]. The cyclo-hexene ring has a half-chair conformation, whereas the cyclo-hexane ring displays a chair conformation being substituted at position 2 by a 3-(4-methyl-phen-yl)prop-2-enoyl group. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link mol-ecules into chains in the [010] direction.

  18. N-(3,4-Dimethyl-phen-yl)-4-hydr-oxy-2-methyl-2H-1,2-benzothia-zine-3-carboxamide 1,1-dioxide.

    Science.gov (United States)

    Siddiqui, Waseeq Ahmad; Ali, Muhammad; Zia-Ur-Rehman, Muhammad; Sharif, Saima; Tizzard, Graham John

    2009-03-28

    1,2-Benzothia-zines similar to the title compound, C(18)H(18)N(2)O(4)S, are well known in the literature for their biological activities and are used as medicines in the treatment of inflammation and rheumatoid arthritis. The thia-zine ring adopts a distorted half-chair conformation. The enolic H atom is involved in an intra-molecular O-H⋯O hydrogen bond, forming a six-membered ring. In the crystal, mol-ecules arrange themselves into centrosymmetric dimers by means of pairs of weak inter-molecular N-H⋯O hydrogen bonds.

  19. Methyl 4-eth-oxy-2-methyl-2H-1,2-benzothia-zine-3-carboxyl-ate 1,1-dioxide.

    Science.gov (United States)

    Zia-Ur-Rehman, Muhammad; Choudary, Jamil Anwar; Elsegood, Mark R J; Akbar, Noshin; Latif Siddiqui, Hamid

    2008-07-16

    In the crystal structure of the title compound, C(13)H(15)NO(5)S, the mol-ecules exhibit weak S=O⋯H-C and C=O⋯H-C inter-molecular inter-actions and arrange themselves into centrosymmetric dimers by means of π-π inter-actions (ring centroids are separated by 3.619 Å, while the closest C⋯C contacts are 3.514 Å). 1,2-Benzothia-zines of this kind have a range of biological activities and are used as medicines in the treatment of inflammation and rheumatoid arthritis.

  20. (E)-2-Meth-oxy-9-(2-meth-oxy-9H-xanthen-9-yl-idene)-9H-xanthene.

    Science.gov (United States)

    Tian, Xiang-Yu; Song, Qin-Hua

    2013-01-01

    The title compound, C28H20O4, was synthesized by a bimolecular Zn-HCl reduction in glacial acetic acid using the meth-oxy-substituted xanthone as a starting material. The crystal structure shows that the 2,2'-meth-oxy-bixanthenyl-idene unit is an E-type conformation anti-folded conformer. The mol-ecule lies on an inversion center. The meth-oxy group is almost coplanar with the attached benzene ring, with a C-O-C-C torsion angle of 179.38 (14)°.