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Abstract: Silver bromide is widely used in photographic film which is prepared by the emulsion method using gelatin, and it is also known that the gelation assists the formation of AgBr with various shapes and sizes. In order to investigate the photocatalytic activity as one of the applications of AgBr, the preparation of shape-controlled AgBr was carried out. It is found that the emulsion method controlled by varying the concentration of gelatin and Br/Ag molar ratios was effective to improve AgBr photocatalytic activity. [Copyright &y& Elsevier]

Newton black films (NBFs) can appear under a wide range of experimental conditions. NBFs define the adhesive states of foams and emulsions, showing their formation is a very general physical phenomenon. We show that the existence of NBFs and their whole experimental behavior can be understood within the theory of wetting transitions. NBFs are experimental realizations of partial wetting or pre-wetting states. Hence, they provide experimental systems to investigate the pre-wetting transition, and the spreading behavior under conditions that are very difficult to realize in other experimental systems. We also introduce two new computational approaches to obtain the disjoining pressure isotherm from canonical simulations, and to estimate the contact angles of droplets of naaoscopic dimensions. [ABSTRACT FROM AUTHOR]

Oil-in-water (O/W) emulsion films stabilized by mixtures of an inulin-based polymeric surfactant INUTEC SP1 and a hexa(ethyleneglycol) mono n-dodecyl ether (C12(EO)6) surfactant were investigated to obtain disjoining pressure isotherms at various NaCl concentrations. A comparison with results on emulsion films stabilized by the individual components was made. At a constant INUTEC SP1 concentration, mixtures with different components' molar ratios were prepared by varying the C12(EO)6 concentration, CS. Below a certain value of CS in the mixtures, Newton black films were obtained, which remained stable to rupture with pressure increase and their stability significantly decreased with further increase in CS. [ABSTRACT FROM AUTHOR]

AgBr/I nanoparticles were prepared in a gelatin colloid medium using the double-jet precipitation method. The difference in growth behaviour of AgBr/I nanoparticles in two types of gelatin, fish gelatin and bovine gelatin, was observed, and was considered to result from differences in conformation and component contents. The average size of AgBr/I nanoparticles prepared in aqueous fish gelatin solution increased with decreasing addition rate of reactants from 4.0 mmol min-1 to 1.7 mmol min-1 or increasing precipitation temperature from 30°C to 60°C. On the basis of the dependence of the growth rate of AgBr/I nanoparticles on precipitation temperature, the activation energy of the growth rate of the nanoparticles was estimated as 20.4 kJ mol-1. The protective role of 4-hydroxy-6-methyl-1,3,3a,7-tetraazaindene (TAI) for AgBr/I nanoparticles made in aqueous fish gelatin solution was explored. The results showed that TAI was adsorbed on the surface of AgBr/I nanoparticles to restrict growth and to deflocculate particles. [ABSTRACT FROM AUTHOR]