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By discharging aerosols from a high-pressure vessel through a nozzle, an improved continuous aerosol dispersion system can disperse nanoparticle agglomerates to almost primary nanoparticle size. The system’s high-pressure dispersion was modelled and numerically simulated using the Taylor expansion method of moments. The strong turbulent shear near the nozzle could achieve the same level as the van der Waals force, which is the main mechanism for deagglomerating nanoparticle agglomerates. The change in nanoparticle size was determined to be proportional to the pressure drop between the nozzle inlet and outlet. Nanoparticle breakup was also observed to be affected by the fractional dimension and primary size of particles.

Phosvitin (Pv) from hen egg yolk was conjugated to dextran (Dex) through the initial stage of Maillard reaction in an aqueous system (Pv:Dex, 1:4 (w/w); Mw of Dex, 40 kDa) at 100 °C for 6 h. The red shift of λmax occurred to Pv after the conjugation reaction from 355 to 362 nm and from 510 to 520 nm of intrinsic and extrinsic fluorescence emission spectra respectively. Circular dichroism spectra demonstrated that partial unordered secondary structure of Pv transformed into α-helix and β-turn after conjugating with Dex. The solubility of Pv–Dex conjugates represented an increase from 53.0% to 79.3% at pH 4.0. The zeta-potential of all tested emulsions decreased with lowering pH from 7.0 to 4.0. The interfacial thickness of Pv (1.0 mg/ml) absorbed onto latex particles at pH 4.0 was prominently increased by conjugation with Dex. Both the highest ESI and the slight fluctuation of D[4,3] of Pv–Dex conjugates illustrated that conjugation of Pv with Dex would be an effective method to improve its emulsion stability against more acidic pH environment.

Mini-hydrocyclones were applied to separate the fine rare earth particles from the suspensions. The effects of the flow rate, split ratio, and feed concentration on the total separation efficiency and grade separation efficiency were studied. The combined effects of the flow rate (1200-1600L/h), split ratio (20-60%) and concentration (0.6-1.0wt%) on the total separation efficiency in mini-hydrocyclones were investigated using a response surface methodology. The optimum operating parameters for a total separation efficiency of 92.5% were: feed flow rate=1406L/h, split ratio=20%, and feed concentration=1wt%.