Controlled Growth of Sonochemically Synthesized Gold Seed Particles in Aqueous Solutions Containing Surfactants

2005 ◽  
Vol 58 (9) ◽  
pp. 667 ◽  
Author(s):  
Kenji Okitsu ◽  
Boon Mian Teo ◽  
Muthupandian Ashokkumar ◽  
Franz Grieser
Keyword(s):  
Aqueous Solutions ◽  
Cationic Surfactants ◽  
Growth Process ◽  
Hexadecyltrimethylammonium Bromide ◽  
Dodecyltrimethylammonium Bromide ◽  
Seed Particles ◽  
Didodecyldimethylammonium Bromide ◽  
Seed Growth ◽  
Gold Seed ◽  
Sonochemical Reduction

Gold seed particles stabilized by citric acid were prepared by the sonochemical reduction of Au(iii) ions in aqueous solutions. These seed particles were grown by the reduction of adsorbed Au(iii) ions by ascorbic acid in aqueous solutions containing cationic surfactants, dodecyltrimethylammonium bromide (C12TAB), hexadecyltrimethylammonium bromide (C16TAB) and didodecyldimethylammonium bromide (DDDAB). The rate of reduction of Au(iii) ions during the seed-growth process was found to be strongly dependent upon the type and concentration of the cationic surfactants. The presence of Ag(i) in the growth solution containing DDDAB affected the size distribution of the gold particles.

scholarly journals Effect of Methanol on Viscosity of Aqueous Solutions of Cationic Surfactants at 298.15 to 323.15 K

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Sujit Kumar Shah ◽  
Sujeet Kumar Chatterjee ◽  
Ajaya Bhattarai
Keyword(s):  
Critical Micelle Concentration ◽  
Aqueous Solutions ◽  
Cationic Surfactants ◽  
Cetyltrimethylammonium Bromide ◽  
Mixed Solvent ◽  
Relative Viscosity ◽  
Dodecyltrimethylammonium Bromide ◽  
Solvent Interactions ◽  
Volume Fractions ◽  
Surfactant Solutions

Viscosity measurements have been made to the solutions of dodecyltrimethylammonium bromide (DTAB) and cetyltrimethylammonium bromide (CTAB) in 0.10, 0.20, 0.30, and 0.40 volume fractions of methanol in methanol-water mixed solvent media at 298.15, 308.15, 318.15, and 323.25 K. Critical micelle concentration (CMC) values have been determined. From relative viscosity for surfactant solutions, related viscosityBcoefficients are calculated and the values are interpreted in terms of solute-solvent interactions.

scholarly journals An Ultrasonic Study of Sphere to Rod Transitions in Aqueous Solutions of Hexadecyltrimethylammonium Bromide.

1982 ◽  
Vol 36a ◽  
pp. 698-700 ◽  
Author(s):  
Sune Backlund ◽  
Harald Høiland ◽  
Ove J. Kvammen ◽  
Eva Ljosland ◽  
V. B. Sokolov ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Hexadecyltrimethylammonium Bromide ◽  
Ultrasonic Study

Metal Ion Chelates of Lipophilic Alkyl Diazinyl Ketoximes as Hydrolytic Catalysts

1999 ◽  
Vol 64 (7) ◽  
pp. 1159-1179 ◽  
Author(s):  
Radek Cibulka ◽  
František Hampl ◽  
Tomáš Martinů ◽  
Jiří Mazáč ◽  
Sonja Totevová ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Metal Ion ◽  
Hydrolytic Activity ◽  
Hexadecyltrimethylammonium Bromide ◽  
Diphenyl Phosphate ◽  
Hydrolysis Of ◽  
Metal Ligand

A series of lipophilic dodecyl hetaryl ketoximes (hetaryl = pyridin-2-yl, pyridazin-3-yl, pyrimidin-2-yl, pyrimidin-4-yl, pyrazin-2-yl as well as their methyl hetaryl homologues was synthesized and hydrolytic activity of their chelates with Co2+, Ni2+, Cu2+ and Zn2+ in a micellar matrix of hexadecyltrimethylammonium bromide or in homogeneous aqueous solutions was investigated using 4-nitrophenyl acetate, 4-nitrophenyl hexanoate and 4-nitrophenyl diphenyl phosphate as model substrates. While Co2+ and Cu2+ chelates are almost inactive, those of Ni2+ and Zn2+ exhibit considerable activity. None of the studied chelates promotes hydrolysis of the used phosphate. The effective species are chelates of the metal : ligand stoichiometry 1 : 3 and 1 : 1 with Ni2+ and Zn2+, respectively, when the ester cleavage proceeds in the micellar matrix. The 1 : 2 stoichiometry was found in aqueous solutions of Ni2+ and Zn2+ chelates of methyl ketoximes.

scholarly journals Sugar Industry: Effect of Dextran Concentrations on the Sucrose Crystallization in Aqueous Solutions

2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
Abdelali Borji ◽  
Fatima-Ezzahra Borji ◽  
Abdelaziz Jourani
Keyword(s):  
Experimental Data ◽  
Aqueous Solutions ◽  
Growth Process ◽  
Sugar Industry ◽  
Nucleation Kinetics ◽  
Metastable Zone Width ◽  
Zone Width ◽  
Industry Effect ◽  
Instantaneous Nucleation ◽  
Metastable Zone

Using the spectrophotometric method, as a new method, the influence of dextran on the sucrose solubility and metastable zone width has been studied. In agreement with the literature the experimental data show that the dextran has a negligible effect on the sucrose solubility. The results also show that this impurity decreases the sucrose metastable zone width. The study of the nucleation kinetics performed, using Nyvlt’s approach, shows that the dextran accelerates the nucleation and that the nuclei are formed in the solution by instantaneous nucleation. The presence of dextran in the system causes a decrease in the growth rate of sucrose. The growth process of sucrose is governed by a Birth and Spread mechanism. The kinetic parameters of sucrose growth in aqueous solutions without and with dextran were estimated.

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