Gold sol

Chow M K and Zukoski C F 1994 Gold sol formation meohanism role of oolloidal stability J. Coll. Int. Sc/. 165 97... 

Roark D, Yphantis DA (1969) Ann New York Acad Sci 164 245 Rinde H (1928) The Distribuhon of the Sizes of Particles in Gold Sols Prepared According to the Nuclear Method. PhD Thesis, University of Uppsala, Uppsala, Sweden Harding SE (1988) Gums and Stabilisers for the Food Industry 4 15 http //www.wyatt.com/... 

Monitoring the pH value during the preparation of gold sol, which leads to the below reported results, it has been observed that pH moves from ca. 3.2, before NaBH4 addition, to ca. 6.9, after NaBH4 addition. In this section a discussion of the influence of the initial pH value on the properties of the colloidal dispersion stabilized by a large amount (PVA/Au = 0.67) or a low amount (PVA/ Au = 0.05) of stabilizer is presented. Proper amounts of HCl or NaOH were used to produce the reported pH values. 

Table 7. Influence of gold sol concentration on particle diameter.

As mentioned in Section 3.1, the pyrolytic carbon XC72R resulted useful for immobilizing gold sol particles owing... 

This study has shown that the immobilization of preformed gold sol on carbon could represent a valid... 

In this paper, suitable gold sol preparations designed for catal5fiic pru poses that fulfil the above-reported prerequisites have been reported. 

After few minutes of gold sol preparation, metal particles have to be immobilized on a suitable support for practical purpose. Normally this step is simply performed by dipping the support in the sol. The metal particles are... 

Yeung S A, Hobson R, Biggs S, Grieser L (1993) Lormation of gold sols using ultrasound. J Chem Soc Chem Commun 378-379... 

Caruso RA, Ashokkumar M, Grieser L (2002) Sonochemical formation of gold sols. Langmuir 18 7831-7836... 

Fig. 6.1 Absorption spectra of gold sols generated from solutions containing 1 x 10 4 mol dm 3 AuCl,, 0.1 wt% PVP, and various concentrations of propan-2-ol [31]...

As reported in the literature by Heard et al. [156], the colour of the gold sol depended strongly on the size of the particles. The blue sol corresponded to 20-30 nm elongated agglomerated particles whereas pink sols corresponded to <20 nm particle size. 

Graham coined the term "colloid" to describe suspensions of small particles in a liquid.(J ) Such particles are generally considered to be from 1 to 5000 nm in diameter and are not easily precipitated, filtered, or observed by ordinary optical microscopes. The topic of this paper is metallic colloidal particles, often called metal sols, with special emphasis on non-aqueous media. Some history of gold sols is appropriate. 

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