This new “shear synthesis” method has been shown to produce gallium and In-Bi alloy nanoparticles in addition to indium nanoparticles. Furthermore, this method produces nanoparticles with a yield of effectively 100%; seemingly, all of the bulk material used to make the nanoparticles is converted to nanoparticles in the process if the sonication is allowed to proceed for a sufficiently long time. However, with the settings used here, the method produces a broad range of nanoparticle sizes. From this limited study, it is unclear what effect the bath temperature and surfactant concentration have on the resulting particles. It seems likely that the bath temperature would change size of the resulting nanoparticles because it changes the viscosity of the PAO. The Taylor formula describing the formation of droplets through shear states that a continuous phase with a larger viscosity will produce smaller droplets, all else being equal . This suggests that the higher the bath temperature, and hence the lower the continuous phase viscosity, the larger the average particle size would be. Additionally, the increased bath temperature increases the diffusion of both the particle and the surfactant, increasing the frequency of both nanoparticle–nanoparticle and nanoparticle–surfactant collisions. Considering the effects of the surfactant concentration, we know that the smaller the nanoparticles, the larger the total surface area between the nanoparticles and the fluid is for the same initial mass of nanoparticle material. Thus, if the surfactant concentration were too low, there would be a particle diameter below which it would be impossible for all of the particles to be stabilized by the surfactant. In this case, the particles would agglomerate to form an interfacial area small enough to be covered by surfactant or fall out of solution. Since we do not see a correlation between the surfactant concentration and particle size, we might assume that all the surfactant concentrations used were above this threshold. Once above this threshold, the surfactant might still have an effect on the process by changing the viscosity and surface tension of the fluid.