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Orthorhombic Crystal System (orthorhombic + crystal_system)
Selected AbstractsConfiguration, conformation and crystal structure of rabdosianin bCRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2005Bao Lin Li Abstract Rabdosianin B, 7,20-epoxy-7,-hydroxy-1,,6,,11,,15,-tetraacetoxy- ent -kaur-16-ene, C28H38O10, was the first isolated from Isodon henryi. It consists of three six-membered rings A, B, C and one five-membered ring D. The fused-ring system A, B and C are in chair, boat and chair conformations, respectively, and ring D is in an envelope conformation, on the basis of NMR and X-ray diffraction analysis. The crystal of rabdosianin B is in orthorhombic crystal system with space group P212121, lattice constants: a = 9.969(1) Å, b = 15.400(3) Å, and c = 17.624(3) Å, Z = 4. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Synthesis of processible doped polyaniline-polyacrylic acid compositesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2009Bhavana Gupta Abstract Processible composites of emeraldine salt form of polyaniline (PANI) with polyacrylic acid (PAA) are synthesized and studied for their structural, electrical, mechanical, thermal, and electrochemical properties. The processible conducting composites of various weight percentage from 20 wt % to 90 wt % (of PANI) have been prepared by mixing the PANI and PAA under vigorous stirring and sonication conditions. Self-standing films of electroactive homogeneous composites are obtained by solution casting method. A significant improvement in processibility, crystallinity, and thermal stability is observed in the composites; however, the electrical conductivity decreased remarkably as the percentage of PANI is decreased in the composites. The 60 wt % PANI-PAA composite showed crystalline structural property with orthorhombic crystal system and cell parameters as a = 5.93Å, b = 7.57Å, and c = 10.11Å. The 60 wt % PANI-PAA composite also showed better thermal stability and highest capacitance amongst all the composites and used as an active material for development of electrochemical capacitors (parallel plate assembly). The processible composites based electrochemical capacitors using 0.5 M NaClO4 -Acetonitril electrolyte showed super capacitance with ease in fabrication and cost effectiveness in comparison to other similar materials based capacitors. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] On the purity of 2-[ortho -anilinyl]-1,3-benzoxazole derived from 2H -3,1-benzoxazine-2,4(1H)dione (isatoic anhydride) [1,2],JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2010Karen M. Button The Lewis acid catalyzed synthesis and chromatographic purification of isatoic anhydride-derived 2-(2,-anilinyl)-1,3-benzoxazole (2) can result in the co-isolation of 2 and a light pink colored impurity (<5%). This latter species has been identified (NMR, single crystal X-ray diffraction, mp) as 2,-hydroxy-2-aminobenzanilide (3), which represents a predictable intermediate in the formation of 2. Compound 3 crystallizes in an orthorhombic crystal system of space group P212121 with four molecules in the unit cell (, = , = , = 90°; a = 6.715 (2) Å, b = 12.100 (4) Å, c = 13.321 (4) Å; V = 1082.2 (6) Å3). Pure 2 is characterized as a colorless, high-melting solid; unlike the dark colored oil that is isolated if 2 contains traces of 3. J. Heterocyclic Chem., (2010). [source] Two dimorphs of 5-methylsulfanyl-1H -tetrazoleACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2004Natalya Fridman 5-Methylsulfanyl-1H -tetrazole, C2H4N4S, crystallizes in dimorphic forms; the ,-form crystallizes at room temperature in the monoclinic crystal system, space group P21/m, and the ,-form crystallizes by sublimation at 423,K in the orthorhombic crystal system, space group Pbcm. In both forms, the molecules occupy crystallographic mirror planes and are connected to one another via N,H,N hydrogen bonds, the amino H atoms being disordered. The two forms differ from one another in their packing; there are polar layers in the ,-form and non-polar layers in the ,-form. [source] Crystallization of a core fragment of the flagellar hook protein FlgEACTA CRYSTALLOGRAPHICA SECTION D, Issue 11 2004Fadel A. Samatey A core fragment of the bacterial flagellar hook protein FlgE was overexpressed, purified and crystallized. The crystal diffracted to 1.6,Å resolution using synchrotron X-radiation. The crystal belongs to the orthorhombic crystal system, with space group P21212 and unit-cell parameters a = 128.4, b = 48.8, c = 96.7,Å. SeMet protein was also overexpressed, purified, crystallized and a set of 2.3,Å MAD data was collected. [source] Crystallization and preliminary crystallographic analysis of N -acetylglucosamine 6-phosphate deacetylase from Escherichia coliACTA CRYSTALLOGRAPHICA SECTION D, Issue 5 2000F. M. Ferreira N -Acetylglucosamine 6-phosphate deacetylase (E.C. 3.5.1.25), an enzyme from Escherichia coli involved in aminosugar catabolism, has been crystallized by the vapour-diffusion technique using phosphate as precipitant. X-ray diffraction experiments show the crystals to belong to the orthorhombic crystal system, with space group P21212. The unit-cell parameters are a = 82.09,(2), b = 114.50,(1), c = 80.17,(1),Å. The crystals diffract to a maximum resolution of 1.8,Å and an initial data set was collected to 2.0,Å. [source] | ||||||||||