Ozone surface

Ozone-nicotine surface chemistry has recently been identified by Destaillats et al. (2006a). Nicotine and other products of tobacco smoking adsorb strongly to indoor surfaces. In the presence of ozone, surface nicotine can form a variety of products (Scheme 13.7). On cotton, high humidity inhibits this reaction. Ozone attacks the pyrrolidinic N, suggesting that other indoor surface bound species with this functionality may be oxidized in this manner. Not only does this chemistry generate volatile by-products, it may explain why indoor nicotine concentrations correlate poorly with exposure to tobacco smoke. This raises the question, what other, similarly functionalized, surface amines may also react with ozone in indoor environments ... 

Croll BT. The installation of GAC and ozone surface water treatment plants in Anglian water, UK. Ozone Sci Eng 1996 18 19-40. 

In general, the quenching step of manufacture presents an opportunity for oxidation of the fine CB po vder. Surface groups can be further enhanced intentionally by oxidation vith acid or ozone. Surface groups formed in this vay are primarily carboxylates and phenolics. An untreated black typically has pH > 6 and volatile content of 0.5-1.5%. Oxidized blacks have pH < 6 and volatile content of 3-10%. 

Macmanus, L. R Walzak, M. J. McIntyre, N. S. Study of ultraviolet light and ozone surface modification of polypropylene. J. Polym. ScL, Part A Polym. Chem. 1999, 37, 2489-2501. 

No Amount of the bound ozone relative to the rubber, mass % Solid resi- due, mass %. pH value after ozonization Surface tension, mN/m Content of carbonyl groups in rubber, mass % Content of carboxyl groups in rubber, mass % Solubility of rubber in toluene, mass % Gel content, mass % Averaged-viscous molecular mass (MM) of rubbers released from rubber samples... 

Recently, Kim et al. carried out CO oxidation on 2 and 6.5 nm Rh nanoparticles capped by poly(vinylpyrrolidone) (PVP) before and after UV/O3 surface treatment [51]. Figure 7.3 shows the catalytic activity, Arrhenius plot, and summary of catalytic turnover rates at 443 K for the CO oxidation reaction on two-dimensional arrays of 2 and 6.5 nm Rh nanoparticles before and after UV-ozone treatment. As shown in Fig. 7.3a, the smaller Rh nanoparticles before UV-ozone treatment show a higher activity than the larger Rh nanoparticles and it is also clear that the turnover frequency (TOF) of the 2 and 6.5 nm Rh nanoparticles increased by a factor of two or three after UV-ozone treatment. The activation energies for 2 and 6.5 mn Rh nanoparticles were obtained from Arrhenius plots of catalytic activity (Fig. 7.3b). Figure 7.3c shows a summary of the catalytic turnover rates at 443 K and the activation energies measured on the Rh nanoparticles before and after UV-ozone surface treatment. The activation energy decreased from 29.4 to 27.8 kcal/mol for the 2 nm Rh nanoparticles and decreased from 31.3 to 28.5 kcal/mol for the 6.5 mn Rh nanoparticles after UV-ozone treatment, as shown in Fig. 7.3c. 

Fig. 7.3 Catalytic activity of the CO oxidation reaction on two-dimensional arrays of Rh NPs. (a) Turnover frequency (TOP) of Rh NPs with temperature, (b) Arrhenius plots of Rh NPs, and (c) summary of TOFs and activation energies of the CO oxidation reaction measured on Rh NPs before and after UV-ozone surface treatment...

Engineering Ru Oxide on Nanoparticles through UV-Ozone Surface Treatment... 

Kim et al. carried out CO oxidation on Ru nanoparticles capped by PVP before and after UV-ozone surface treatment, respectively [51]. UV-ozone surface treatment... 

Mathieson 1, Bradley RH. Improved adhesion to polymers by UV/ozone surface oxidation. Int J Adhes Adhes. 1996 16 29-31. 

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