BREAK-UP MECHANISM OF METAL DROPLETS GENERATED BY AN ELECTROHYDRODYNAMIC TECHNIQUE

Nanometer powders can be produced by an electrohydrodynamic technique. The breakup mechanism of the metal droplets generated by the electrohydrodynamic technique was analysed. It showed that the applied voltage, the electric field Btrength, the properties of the molten metal and the volumetric flow rate of the molten metal directly effect the breat-up extent of the metal droplets.

CHARACTERIZATION OF NANOSTRUCTURED MATERIALS BY ANALYTICAL ELECTRON MICROSCOPY

The analytical electron microscopy has been used to characterize the morphology,structure and composition of the nanostructured material of Sn- Bi alloy prepared by a modified electrohydrodynamic technique. The electron diffraction pattern and the corresponding contrast image for the discrete particles with a diameter smaller than 4 nm have been obtained.It is shown that the nanocrystalline Sn-Bi alloy particles comprise a single crystal of Bi-containing β-Sn solid solution or of Sn-containing Bi solid solution. A direct preparation procedure of the samples during the electrohydrodynamic rapid solidification process has been developed for electron microscopic observation.

Synthesis,characterization,and in vitro digestion of electrosprayed and freeze-dried probiotics encapsulated in soy protein isolate-sunflower oil emulsions

This research evaluated the microencapsulation of the probiotic,Streptococcus thermophilus,in soy protein isolate(SPI)and sunflower oil(SO)emulsions using electrospraying and freeze-drying.Emulsions were formed with SPI(3-15%w/v),Tween 80®(2%w/v),and SO(5%w/v)after homogenization and ultrasonication.The Emulsion Stability Index(ESI),Emulsifying Ability Index(EAI),ζ-potential,particle size,Polydispersity Index(PDI),conductivity,and viscosity were evaluated to compare the emulsion properties at varying SPI:SO concentrations.After probiotic inclusion,the emulsions were electrosprayed and freeze-dried,and the microcapsules’properties were evaluated(encapsulation efficiency,loss of viability,drying yield,surface hydrophobicity)and characterized(Fourier Transform Infrared Spectroscopy,Scanning Electron Microscopy,Laser Scanning Confocal Microscopy,and Differential Scanning Calorimetry).Theζ-potential(-51.51 mV)and other emulsion parameters obtained after ultrasonication indicated that the emulsion stability had improved.The secondary protein structure modifications were revealed by the emulsions’FTIR spectra,with significant increments in theα-helix andβ-turn of the ultrasonicated samples compared to SPI.The electrosprayed microcapsules(13%SPI,5%SO)demonstrated the highest encapsulation efficiency(90.51%)and the lowest loss of viability(1.05 log⋅CFUmL^(-1)).The probiotics in the microcapsules were validated by the LSCM images and FTIR spectra.The differences in the morphological properties of freeze-dried and electrosprayed particles were observed through SEM.The electrosprayed microcapsules demonstrated the highest intestinal phase survival(77.03%)of probiotics under simulated gastrointestinal conditions,suggesting targeted probiotic delivery with potential for inclusion in nutraceuticals and functional foods.