RESUMEN
The aminothiazole-functionalized adsorbent (CEAD) could exclusively remove and to selectively recover copper. The adsorption and separation properties of Cu(II) onto CEAD from aqueous media, with or without salts such as NaNO3, Ca(NO3)2 and Ni(NO3)2, were systematically compared by carrying out single, binary and multiple component static and dynamic experiments. In binary systems, the adsorption capacities of Cu(II) were obviously increased by 39.47%, 47.37% and 57.89% with Ni(NO3)2, NaNO3 and Ca(NO3)2, respectively. Besides, simulation study was performed to selectively recover Cu(II) from multi-component aqueous media, with the separation factor of only 54.91 in aqueous media without salts. The separation factor became infinite in the presence of NaNO3 and the enhancement ratio for Cu(II) was raised by 126.31%. Dynamic adsorption could separate Cu(II) and Ni(II) completely and the amount of effluent for pure Ni(II) increased to 127 BV with the help of NaNO3. In the predominant chelating mode simulated by density functional theory calculation, a metal ion coordinated with three nitrogen atoms and formed a chelating complex with two five-membered rings, and Cu(II) showed stronger coordinating ability than Ni(II) did. Meanwhile, anions exerted significant beneficial effects by electrostatic screening, and thus strengthened the exclusive removal and selective recovery of Cu(II).
Asunto(s)
Cobre/aislamiento & purificación , Tiazoles/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Cinética , Sales (Química)/químicaRESUMEN
An electrokinetic route was developed for the synthesis of Ni(OH)2 nanotubes in the nanochannel of anodic alumina oxide (AAO) template. The nanotubes in the template were then converted to NiO nanotubes by calcination in air at 300 degrees. Uniform ordered nanotubes were obtained after selecting proper experimental conditions, such as the ionic concentration, the reaction time and the kind of nickel salts. X-ray diffraction (XRD) analysis indicated that the as-prepared Ni(OH)2 nanotubes were crystalline. Thermogravimetric analysis (TGA) was employed to determine the correlation between temperature and weight lose of the nanotubes. The transmission electron microscope (TEM) and scanning electron microscope (SEM) were used to characterize the morphology and structure of the nanotubes.
RESUMEN
Two chromium(III) complexes of glucosaminic acid were synthesized by neutralization and exchange reaction. The formation of 1 : 1 and 2 : 3 (Cr : glucosaminate) complexes was confirmed by elemental analyses and spectroscopic studies. The effect of the complexes on decreasing blood sugar was investigated on type-2 diabetes model rats induced by tetraoxypyrimidine. The results indicated that the effect on decreasing blood sugar was comparable to that of picolinate chromium complex (Cr(pic)(3)) currently used world wide.
Asunto(s)
Glucemia/metabolismo , Compuestos de Cromo/farmacología , Glucosamina/análogos & derivados , Aloxano/toxicidad , Animales , Compuestos de Cromo/síntesis química , Compuestos de Cromo/química , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/tratamiento farmacológico , Modelos Animales de Enfermedad , Glucosamina/síntesis química , Glucosamina/química , Glucosamina/farmacología , Masculino , Ácidos Picolínicos/síntesis química , Ácidos Picolínicos/química , Ácidos Picolínicos/farmacología , RatasRESUMEN
A highly selective and sensitive chromogenic and fluorogenic dual signal responding fluoride-sensor 1, comprising a Ru-bipy fluorophore (bipy = 2,2'-bipyridine) and a 2,4-dinitrophenylhydrazone chromophore was prepared and spectroscopically characterized. Uv-vis titrations with F- revealed the appearance of a new intense absorption band centered at about 580 nm which was accompanied by a dramatic change in color from yellow to magenta, with the association constant logK being 6.71 +/- 0.04. Fluorescence spectra showed that upon addition of F-, the emission intensities enhanced significantly without any change in the excited and emission wavelengths, suggesting a potential photoinduced electronic transfer (PET) signaling transduction mechanism. An easy-to-prepare test paper which was obtained by putting a filter paper into an acetonitrile solution of 1, can detect F- in aqueous media, indicating the potential application for detecting F- in natural aqueous environments without any spectroscopic instrumentation. Spectroscopic titrations of the free ligand were also studied for comparison.
RESUMEN
A test paper for high-selectivity detecting fluoride ion in natural aqueous environments without any spectroscopic instrumentation was achieved by using Ru-bipy based quinonehydrazone as a chromo- and fluorogenic hybrid chemosensor.