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This paper describes more in detail the methodology, the measurements and the results of the ASQ method. The Airborne Sound Quantification method aims at identifying the acoustical contribution of the different body panels surrounding a cavity. The contribution of different body panels is the product of the acoustical strength (or volume velocity) of each panel with the corresponding acoustic transfer function between the panel and the interior microphone position. These volume velocities are the product of the corresponding normal velocity and the surface. The normal velocity has been measured by means of accelerometers attached to the different subpanels. In the next step, the acoustical FRF's are measured in an indirect way using the reciprocity principle. This means that the pressure response at all the subpanels is measured when the acoustical excitation takes place at the target interior noise microphone position. A high quality low frequency sound source has been used.

Separation of roughly equal volume mixtures of methanol and gasoline into two phases at low temperature may cause problems for vehicles that are designed to operate on these mixtures. Cosolvent alcohols (C2-C12) and surfactants were evaluated as additives for enhancing phase stability at -25°C of a blend containing SO volume percent methanol, 40 percent isooctane, and 10 percent toluene (simulating a 50/50 methanol/gasoline mixture). For alcohol cosolvents, the amount required decreased with increasing carbon number (number of carbon atoms per molecule) from about 50 percent with C2 to about 6 percent for C8 through C12 A simple cost analysis indicated that decanol (C10) provided the minimum treatment cost for preventing separation at -25°C: $0.13/galloπ. Of the various commercial nonionic surfactants and various anionic fatty acid surfactants evaluated, only palmitic acid (C16) showed good effectiveness.