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61.
Marina S. Fonari Yurii A. Simonov Victor Ch. Kravtsov Janusz Lipkowski Gabriele Bocelli Edward V. Ganin Vladimir O. Gelmboldt 《Journal of chemical crystallography》1999,29(12):1245-1254
Synthesis and single-crystal X-ray structures are recorded for three adducts of SbF3 with different azacrown ethers. [SbF3·H2O·L1], 1, (L1 = 12,13-benz-1,10-di(azamethyl)-4,7-dioxacyclotetradecane-1,14-dione), triclinic,
, a = 11.234(2), b = 11.691(2), c = 8.869(2) Å, = 94.66(3), = 113.12(3), = 67.82(3)°, Z = 2. [SbF3Cl·H2O·(HL2)], 2, (L2 = monoaza-18-crown-6), orthorhombic, P212121, a = 8.763(2), b = 13.003(3), a = 16.836(3) Å, Z = 4. [(SbF3)2Cl2·(H2L3)], 3, (L3 = 1,10-diaza-18-crown-6), triclinic,
, a = 8.284(2), b = 9.016(2), c = 9.134(2) Å, = 82.92(3), = 65.24(3), = 63.38(3)°, Z = 1. All three structures include SbF3 neutral molecules in the pyramidal mode and the antimony second coordination sphere is completed up to six in different fashions. In 1 the dimeric (SbF3)2 adducts are made up due to the involvement of the symmetry-related fluorine atom in coordination. The distorted octahedron is then completed by water molecule and carbonyl oxygen of L1. The neutral molecules are joined by coordination and hydrogen bonds in the infinite ribbons. 2 and 3 are both comprised of neutral and charged species also bounded via coordination and hydrogen bonds. L2 and L3 in the complexes adopt the form of single and double-charged cations, respectively. The inorganic backbone unites the neutral SbF3 molecules and chloride anions in the alternative mode. The sixth coordination site in the antimony polyhedron is completed by the water molecule in 2 and the ethereal oxygen atom in 3. Alignment of the inorganic entities within the structures of 2 and 3 is strikingly similar. Hydrogen bonding patterns are discussed. 相似文献
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Thin films of molybdenum trioxide were deposited on glass substrates employing direct current (DC) magnetron sputtering by
sputtering of molybdenum at different oxygen partial pressures in the range 8 × 10−5–1 × 10−3 mbar and at a substrate temperature of 473 K. The glow discharge characteristics of magnetron cathode target of molybdenum
were studied. The influence of oxygen partial pressure on the structural and optical properties of molybdenum trioxide films
was investigated. The films formed at an optimum oxygen partial pressure of 2 × 10−4 mbar were polycrystalline in nature with orthorhombic α- phase and an optical band gap of 3.16 eV. The refractive index of
the films formed at an oxygen partial pressure of 2 × 10−4 mbar decreased from 2.08 to 1.89 with increase of wavelength from 450 to 1,000 nm, respectively.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006. 相似文献
65.
William R Cullen Mathew Dodd Basil U Nwata Deborah A Reimer Kenneth J Reimer 《应用有机金属化学》1989,3(4):351-353
Inorganic arsenic(III) and arsenic(V), methyl-arsenicals, antimony(III), and antimony(V), and butyltin derivatives are present in the shells of molluscs found in the coastal waters of British Columbia. 相似文献
66.
A series of novel tetraphenylantimony derivatives of exo‐7‐oxa‐bicyclo[2,2,1] heptane (ene)‐3‐arylamide‐2‐acid of the general formula Ph4SbO2CCHCHCH2CH2CH(O)HCONHAr (Ar = Ph,4‐ClC6H4, 4‐BrC6H4, 3‐BrC6H4, 4‐F‐3‐ClC6H3 and 4‐MeC6H4) have been synthesized and characterized by elemental analysis, IR, 1H NMR and mass spectra. The crystal structure of Ph4SbO2CCHCHCH2CH2CH(O)HCONHC6H4CH3·CHCl3 was determined by X‐ray diffraction. Five human neoplastic cell lines (HL‐60, KB, Bel‐7402, BGC‐823 and HCT‐8) were used to screen these compounds. The results indicate that these compounds at 10 µM show certain in vitro antitumor activities. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Nafion‐coated antimony film electrode (NCAFE) was prepared in situ by simultaneously plated antimony with analytes, and applied to the determination of trace Pb(II) and Cd(II) in non‐deaerated solutions by differential pulse anodic stripping voltammetry (DPASV). Various experimental parameters, which influenced the response of the NCAFE to those metals, were thoroughly optimized and discussed. The results indicated that the sensitivity and resistance to surfactants at the NCAFE were remarkably improved with relative to the antimony film electrode (AFE). In the presence of 5 mg·L?1 gelatin, the peak heights at the NCAFE showed 4‐fold enhancement for Pb and a 9‐fold enhancement for Cd over a bare AFE. Reproducibility of the sensor was satisfactory, and the relative standard deviations were 4.8% for 20 μg·L?1 Pb and 3.2% for 25 μg·L?1 Cd (n=15) with preconcentration time of 180 s. The determination limits (S/N=3) of this sensor were determined to be 0.15 μg·L?1 for Pb and 0.30 μg·L?1 for Cd with accumulation time of 300 s. The NCAFE was successfully applied to determining Pb(II) and Cd(II) in vegetable and water samples with satisfactory results. 相似文献