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41.
A tripodal receptor functionalized with a stilbazolium dye derivative has been designed, synthesized and has been used for the colorimetric discrimination between certain ω-amino acids in mixed DMSO-water 90:10 v/v solutions. 相似文献
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Brbara L. Almeida Joanna M. Ramos Otvio Versiani Marta Sousa Claudio Alberto Tllez Soto Ana Lúcia Ramalho Mercê Antnio Slvio Mangrich Judith Felcman 《Polyhedron》2008,27(18):3662-3668
A new complex of Cu(II) of stoichiometry [Cu(PCr)(H2O)] was prepared from aqueous solution at pH 6. Its synthesis, characterization, thermogravimetric, vibrational spectroscopy, and electron paramagnetic resonance analyses were described and suggest that phosphocreatine (PCr) in solid state is acting as a tridentate ligand (the nitrogen atom of the guanidine group and the oxygen atoms of the phosphate group and the carboxylate group being the donor atoms). The fourth position is occupied by a water molecule. These results were confirmed through computational calculations (DFT/B3LYP:6-311G theoretical procedure). The tetra coordination of Cu(II) arranged in a quadratic planar geometry was found to be more stable in the DFT calculations. The calculated vibrational spectrum agrees well with the FT-IR experimental spectrum. 相似文献
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Densities, refractive indices and dynamic viscosities of binary and ternary mixtures composed of isopropyl acetate, isopropanol, 1-octyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide ([C8mim][NTf2]) have been determined at 298.15 K and atmospheric pressure. The excess molar volumes and dynamic viscosity changes of mixing have been calculated and correlated using the Redlich–Kister polynomial equation. Isobaric vapour–liquid equilibrium (VLE) data have been determined experimentally for these binary and ternary systems at 101.32 kPa. The equilibrium data have been adequately correlated by means of Wilson, NRTL, and UNIQUAC equations for the liquid phase activity coefficient. 相似文献
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Juan Manuel Jiménez‐Soto Yolanda Moliner‐Martínez Soledad Cárdenas Miguel Valcárcel 《Electrophoresis》2010,31(10):1681-1688
This paper describes for the first time the use of single‐walled carbon nanohorns (SWNHs) as pseudostationary and stationary phases for EKC and CEC, respectively, taking advantage of their characteristic features, such as conical‐end termination, formation of spherical assemblies dahlia‐flower like superstructure and easy functionalization. The use of SWNHs as pseudostationary phase for EKC required the study of their dispersion in different surfactants as well as their compatibility with the electrophoretic system. The carboxylation and subsequent immobilization of carboxylated SWNHs in fused‐silica capillary to obtain useful, reproducible and stable stationary phases for CEC has also been investigated, with promising results. The electrophoretic separations obtained for water‐soluble vitamins in both modalities (EKC and CEC) have been systematically compared with those obtained with single‐walled carbon nanotubes. 相似文献
48.
Suitability of a pyridinium ionic liquid as a solvent in desulfurization has been analyzed. (Liquid + liquid) equilibria for ternary systems composed by 1-hexyl-3,5-dimethyl pyridinium {bis[trifluoromethylsulfonyl]imide, thiophene, and three hydrocarbons representative of fuel (n-heptane, 2,2,4 trimethylpentane, and toluene) have been determined at T = 298.15 K and atmospheric pressure. High solubility of thiophene in the ionic liquid and also of toluene have been found, being this solvent practically immiscible with 2,2,4 trimethylpentane and heptane. Equilibrium data of these systems have been well correlated with UNIQUAC equations finding the highest deviations for the ternary system involving toluene. NRTL model drove to worse results being considered as not suitable model to correlate the experimental results. 相似文献
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Salinas Y Climent E Martínez-Máñez R Sancenón F Marcos MD Soto J Costero AM Gil S Parra M de Diego AP 《Chemical communications (Cambridge, England)》2011,47(43):11885-11887
Silica nanoparticles containing polyamines and thiol groups have been used as probes for the selective detection of Tetryl. 相似文献