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a b s t r a c tA top down approach based on emulsification-evaporation technique was used to prepare nanodispersion of a-tocopherol. Physicochemical properties of the prepared nanodispersions were investigated under combination of the processing parameters (pressure and cycle) and ratio of aqueous:organic. Storage study was performed for 3 months to evaluate the stability of all the prepared nanodispersions. The results showed that homogenization pressure have significant (P < 0.05) influence on the droplet diameter and size distribution. On the contrary, the processing cycle had not significant (P > 0.05) effect on the droplet diameter and size distribution of the prepared nanodispersion. Droplet diameters in the range of 90-120 nm were obtained for the prepared a-tocopherol nanodispersions. During storage duration, there were no significant (P > 0.05) changes in mean diameters while the concentrations of a-tocopherol were significantly (P < 0.05) reduced for all prepared nanodispersions. In general, it is shown that emulsification-evaporation technique can be used as a suitable technique for the production of a-tocopherol nanodispersions with narrow size distribution.

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Bi-chained surfactants, e.g. sodium dialkylbenzenesulphonates, can spontaneously form vesicles when salts (e.g. NaCl) are added to water. Critical vesicle concentrations can be readily determined. The kinetics and mechanism for the breakdown and formation of vesicles will be discussed. A mechanism for assembly/disassembly is proposed. Organic dyes can be encapsulated inside the vesicles and their release rates can be monitored using flow experiments. It is found that the vesicle bilayer provides a rather low energy barrier to the transport of the dye from the vesicle core to the external aqueous medium.

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This paper presents a unique synergistic behavior between a graphene oxide (GO) and graphene nanoplatelet (GnP) composite in an aqueous medium. The results showed that GO stabilized GnP colloid near its isoelectric point and prevented rapid agglomeration and sedimentation. It was considered that a rarely encountered charge-dependent electrostatic interaction between the highly charged GO and weakly charged GnP particles kept GnP suspended at its rapid coagulation and phase separation pH. Sedimentation and transmission electron microscope (TEM) micrograph images revealed the evidence of highly stable colloidal mixtures while zeta potential measurement provided semi-quantitative explanation on the mechanism of stabilization. GnP suspension was confirmed via UV-vis spectral data while contact angle measurement elucidated the close resemblance to an aqueous solution indicating the ability of GO to mediate the flocculation prone GnP colloids. About a tenfold increase in viscosity was recorded at a low shear rate in comparison to an individual GO solution due to a strong interaction manifested between participating colloids. An optimum level of mixing ratio between the two constituents was also obtained. These new findings related to an interaction between charge-based graphitic carbon materials would open new avenues for further exploration on the enhancement of both GO and GnP functionalities particularly in mechanical and electrical domains.

a b s t r a c tThe purpose of this study was to prepare and characterise water-soluble phytosterol nanodispersions for food formulation. The effects of several factors were examined: four different types of organic phases (hexane, isopropyl alcohol, ethanol and acetone), the organic to aqueous phase ratio and conventional homogenisation vs. high-pressure homogenisation. We demonstrated the feasibility of phytosterol nanodispersions production using an emulsification-evaporation technique. The results showed that hexane was able to produce the smallest particle size at a mean diameter of approximately 50 nm at monomodal distribution. Phytosterol nanodispersions prepared with a higher homogenisation pressure and a higher organic to aqueous phase ratio resulted in significantly larger phytosterol nanoparticles (P < 0.05). Phytosterol loss after high-pressure homogenisation ranged from 3% to 28%, and losses increased with increasing homogenisation pressure. Elimination of the organic phase by evaporation resulted in a phytosterol loss of 0.5-9%.

Greenockite (CdS) nanostructured thin films are deposited on soda and FTO conducting glass substrates by aerosol‐assisted (AA)CVD using a single‐source precursor bis‐(N,N‐dicylcohexyldithiocarbamato)(pyridine)cadmium(II), Cd[S2CNCy2]2.py (1), in pyridine, toluene, and THF solutions in the temperature range 350–450 °C. The precursor 1, characterized by physicochemical methods, undergoes facile thermal decomposition at 350 °C to give a stable residual mass of CdS. The thin films deposited from pyridine solution, and characterized by X‐ray diffraction (XRD), UV‐vis spectroscopy, field‐emission scanning electron microscopy (FESEM), and energy dispersive X‐ray (EDX) techniques, exhibit a band gap of 2.4 eV and a photocurrent density of 1.3 mA cm−2 at 0.4 V versus Ag/AgCl/3M KCl, suggesting their suitability for application in photoelectrochemical (PEC) cells.