These properties make these 2 hybrid nanoparticles fascinating candidates for a variety of applications in catalysis and life science. UV-VIS absorption spectrum of Ag nanoparticles obtained in water-AOT-dodecane microemulsion and water-AOT-cyclohexane microemulsion. The inner Ag nanocrystals have dominant (111) planes and are optically active, as shown by X-ray powder diffraction (XRD) and UV-vis measurement, respectively. Embedded in amorphous SiO 2, the Ag nanoparticles are highly stable, while the unprotected Ag nanocrystals underwent fast aggregation. The morphologies of the hybrid nanoparticles and the H 2-induced cavities can be easily tuned by the molar ratio of AgNO 3 to NaBH 4 and the volume ratio of AgNO 3 aqueous solution to TEOS. In many cases, H 2 gas bubbles, which were produced during the reduction of Ag +, were found to influence the structures of Ag nanocrystals. H 2O) and tetraethyl orthosilicate (TEOS) to this microemulsion leads to the formation of hierarchically-organized 2 hybrid nanoparticles with Ag nanocrystals randomly distributed inside amorphous SiO 2, as proved by transmission electron microscopy (TEM) and high-resolution electron microscopy (HRTEM) observations.Successive addition of sodium borohydride (NaBH 4), ammonium hydroxide (NH 3 The relative standard deviation (n = 6) obtained at an RB concentration of 3 µmol dm(-3) was 3%.A water-in-oil microemulsion was prepared by using nonionic surfactant Triton X-100, 1-hexanol, cyclohexane and AgNO 3 aqueous solution with a concentration of 0.2 mol L −1. ![]() Under the experimental conditions optimized for a flow-injection determination of RB based on the new reversed micellar-mediated CL reaction with Ce(IV), a detection limit of 0.08 µmol dm(-3) RB was achieved, and a linear calibration graph was obtained with a dynamic range from 0.5 to 20 µmol dm(-3). The reliability of the measuring principle has been tested by. This kind of system mainly has two advantages: (1) lipase molecules can be entrapped in water-containing microdrops, avoiding direct contract with unfavorable organic medium and retaining their catalytic activity. All the other chemicals used were of analytical grade and were used without further purifications. The solubility of sodium chloride in the binary organic or aqueousorganic solvent mixtures methanol + cyclohexane, water + cyclohexanol, and water + benzyl alcohol as well as in the ternary mixtures water + (ethanol or benzyl alcohol) + cyclohexanol at 298.15 K and ambient pressure has been determined using a gravimetric method. The reactions take place at the oil/water interface and the products are distributed to the oil phase or the water phase 17. Due to the continuous collisions and coalescence of the droplets of water-in-oil. An improved activity of Horseradish peroxidase (HRP) in the w/o microemulsion of CTAB with an increase in n-hexanol concentration and water/surfactant weight. Sulfuric acid (H 2 SO 4), cyclohexane, n-methyl butyrate and n-butyl acetate were purchased from Tianjin chemical reagent Co. Cyclohexane, n-hexanol, Triton X-100 are the components of the microemulsion. The effect of the experimental variables, i.e., oxidant concentration, sulfuric acid concentration, the mole fraction of 1-hexanol, water-to-surfactant molar concentration ratio, flow rate, upon the CL intensity was evaluated. Hexanoic acid, hexanol, butanol and n-ethyl butyrate were all from Shanghai chemical reagent factory (China). dynamics of the water-in-oil CTAB/n-pentanol/n-hexane/. Rapid spectral changes of an intermediate in the RB-Ce(IV) reaction in the aqueous and reversed micellar solutions were successfully observed using a stopped-flow method. is enough to emulsify the excess oil and water in form of very small emulsion droplets. Bearing on the enhancement effect of the CTAC reverse micelles on the RB-Ce(IV) CL, several studies including stopped-flow, fluorescence and electron spin resonance (ESR) spectrometries were performed. The CL emission from the oxidation reaction of RB with Ce(IV) was found to be stronger in the CTAC reversed micellar solution compared with an aqueous solution. ![]() The chemiluminescence (CL) emission, observed when rhodamine B (RB) in 1-hexanol-cyclohexane was mixed with cerium(IV) sulfate in sulfuric acid dispersed in a reversed micellar medium of cetyltrimethylammonium chloride (CTAC) in 1-hexanol-cyclohexane/water, was investigated using a flow-injection system.
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