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111.
In this study, polyindole (PIN)/TiO2 nanocomposites were synthesized with and without the presence of sodium dodecylsulfate, anionic surfactant, with two different PIN contents. The synthesized materials were subjected to various characterizations namely: particle size, apparent density, conductivity, dielectric constants, magnetic susceptibility, elemental analysis, Fourier transform infrared spectroscopy spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Characterization results revealed the successful preparations of PIN/TiO2 hybrid nanocomposites. Electrokinetic properties of all the materials were determined by zeta (ζ)-potential measurements in aqueous and nonqueous media. Effects of pH, temperature, presence of various electrolytes, and surfactants on electrokinetic properties of the materials were examined. 相似文献
112.
We present pp-waven solution to the generalized Einstein-Maxwell field theory introduced by Horndeski and to Mansouri-Chang theory of gravitation. 相似文献
113.
New conditions have been developed for the olefination of diazo compounds catalysed by methyl trioxorhenium. The new system is suitable for unreactive diazo compounds and its utility is demonstrated by the olefination of 3-diazopiperidin-2-one with a range of aromatic, heterocyclic and alkylaldehydes. 相似文献
114.
Veysel T Yilmaz Omer AndacTuran K Yazicilar Halil KutukYunus Bekdemir William T.A Harrison 《Journal of Molecular Structure》2002,608(1):71-76
The local structure of molten LaCl3 was investigated by X-ray absorption fine structure of the La K-edge. The nearest La3+-Cl− distance and coordination number were 2.89±0.01 Å and 7.4±0.5 from the curve fitting of the first peak in the Fourier transform magnitude |FT|. The coordination number larger than 6 suggests that the local structure of molten LaCl3 is not a simple octahedral coordination (LaCl6)3−, but 7-fold (LaCl7)4− and/or 8-fold (LaCl8)5− complexes. The first La3+-La3+ distance, of which correlation was observed as a weak second peak in the |FT|, was evaluated to be 4.9 Å. It suggests that the distorted corner-sharing connection of the complex species is predominant in the melt, in contrast with molten YCl3 in which the edge-sharing connection of the 6-fold (YCl6)3− mainly exists. 相似文献
115.
Süheyla Özbey F. Betül Kaynak Mahmut Toŭrul Nadir Demirel Halil Hoşgören 《Journal of inclusion phenomena and macrocyclic chemistry》2003,45(1-2):123-128
A new complex of a chiral monoaza-crown ether, [R-(-)-2-ethyl-N-benzyl-4,7,10,13-tetraoxa-8,9-benzo-1-azacyclopentadec-8-ene...NaClO4], has been prepared and studied by x-ray diffraction. The compound crystallizes in space group P21 with cell dimensions a = 8.721(1), b = 16.318(2), c = 8.905(1) Å, = 100.80(1)°. The sodium cation is heptacoordinated and located significantly out of the best plane of the macrocycle ring. The donor atoms of the macrocycle are in the half-chair arrangement. 相似文献
116.
Ergül S 《Journal of chromatographic science》2004,42(3):121-124
The M(DEDTC)2 (M = Cu, Co, or Ni) and M(PyDTC)2 (M = Cu or Co) complexes prepared by reactions of sodium diethyldithiocarbamate and ammonium pyrollidinedithiocarbamate with metal (II) nitrates are examined for qualitative analysis and separation using thin-layer chromatography systems. These complexes and their mixtures are spotted to the activated thin layers of silica gel 60GF254 (Si-60GF254) with a 250-microm thickness. Pure toluene and a toluene-cyclohexane mixture (3:1, v/v) are used as mobile phases for running of the complexes. These chromatographic systems are successfully used for qualitative analysis of corresponding metal cations and separation of components in both M(DEDTC)2 and M(PyDTC)2 complex mixtures. 相似文献
117.
Mahmut Toğrul Nadir Demirel Betül Kaynak Süheyla Özbey Halil Hoşgören 《Journal of inclusion phenomena and macrocyclic chemistry》2004,50(3):165-171
The X-ray crystal structure of IX, perchlorate salt of R-(?-2-ethyl-N-benzyl-4,7,19,13-tetraoxa-8,9-benzo-1-azacyclopentadec-8-ene has been determined. In the molecule, the protonated nitrogen atom participates in two N-H?O hydrogen bonds. The unusually high proton affinity of aza crown ether leads to the formation of diastreomer instead of complex formation with chiral R-(+)-1-phenyl ethyl ammonium perchlorate and S-(?)-1-phenyl ethyl ammonium perchlorate. The complex ability of host ethers was evaluated in terms of structural modification. 相似文献
118.
Direct ring-opening of the epoxide ring in 1-(5′--trityl-2′,3′-anhydro-β-D-lyxo-furanosyl) uracil (1) by lithium acetylide or vinylmagnesium bromide/cuprous iodide affords the corresponding 5′--trity]-3′--substituted-3′-deoxy--uridine species. 相似文献
119.
Modified natural diatomaceous earth (DE) is a principal component of the stationary phase in normal thin-layer chromatography (TLC) applications and is mixed with commercial silica gel 60GF254 (Si-60GF254). Modification is carried out by flux calcination and refluxing with acid. Natural DE, modified DEs [flux calcinated (FC)DE and FCDE-I), and Si-60GF254 are characterized by scanning electron microscopy and Fourier-transform-IR spectroscopy. Particle size, specific surface area, pore distribution, pore volume, and surface hydroxyl group density parameters of materials are determined by various techniques. FCDE-I and Si-60GF254 are investigated for their usefulness in the stationary phase of TLC both individually and in composition. Commercially available red and blue ink samples are run on layers of Si-60GF254 and FCDE-I individually, and on various FCDE-I and Si-60GF254 mixtures. Butanol-ethanol-2M ammonia (3:1:1, v/v) and butanol-acetic acid-water (12:3:5, v/v) mixtures are used as mobile phases. The polarities of stationary phases decrease, and the retention factor (Rf) values of ink components increase when the FCDE-I content of the stationary phase increases. The properties of the stationary phase can be optimized by adding FCDE-I to Si-60GF254. This study may be useful in understanding both the systematic effects of stationary phase properties [e.g., specific surface area and surface hydroxyl group density, aOH(s)] and those of the mobile phase (e.g., polarity and acidity) on Rf values and the separability of components. 相似文献
120.
A chiral Schiff base ligand (H2L) was obtained by condensing 2-hydroxynaphthalene-1-carbaldehyde with substituted (1R,2R)-(–)-diaminocyclohexane. Chiral Schiff base complexes [CuL], [NiL], [ZnL] and [MnLOH] have been synthesized and characterized by elemental analyses,
M, i.r., u.v.–vis. and 1H-n.m.r. and magnetic measurements. 相似文献