Chemical lifetime of sulfuric acid aerosol. Annual report
A flow reactor has been constructed to study the rate of neutralization of H2SO4 aerosol by NH3. Monodisperse H2SO4 aerosol was generated by a Berglund-Liu vibrating orifice aerosol generator and mixed with NH3 from a permeation tube. The ammonium fraction was measured as a function of time by an instrument capable of distinguishing between the acid and ammonium fractions of sulfate aerosol in real time. Preliminary results indicate that for 'clean' H2SO4 aerosol (i.e., no surface contaminants) the neutralization rate is controlled by the diffusional mass transfer of NH3 to the H2SO4 droplets.
SCCS OPINION ON Titanium Dioxide (nano form) as UV-Filter in spray ::: SCCS ::: The Committee shall provide Opinions on questions concerning health and safety risks (notably chemical, biological, mechanical and other physical risks) of non-food consumer products (for example cosmetic products and their ingredients, toys, textiles, clothing, personal care and household products such as detergents, etc.) and services (for example: tattooing, artificial sun tanning, etc.).