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Gold atomic aggregates are fabricated by vapor-depositing Au atoms onto a silicone oil surface and the microstructure evolution is investigated by atomic force microscopy (AFM) observation. It is found that the Au aggregates are composed of Au circular nanoparticles with diameter around 45 nm, which is independent with the nominal film thickness d. As d increases from 1 nm to 15 nm, the height of the nanoparticles increases from 15 nm to 25 nm, indicating the geometric shape of the Au nanoparticles evolves from plateau to spherical. Furthermore, the roughness analysis shows that the mean surface roughness increases linearly with d in the range of 1 nm–15 nm, which is quite different from the findings in Ag system. The anomalous microstructure evolution of Au aggregates suggests that the growth of Au aggregates may be dominated by the shadowing effect.

By thermal evaporation method, gold (Au) atomic aggregates were fabricated on a silicone oil surface and the aggregation mechanism was investigated. It is found that the apparent surface coverage ($\rho$) of the Au aggregates dropped obviously, from 15% to 12% as the oil temperature (T) increased from 285K to 353K. Meanwhile, the average width of the aggregates gradually increased from 0.36$\mu$m to 0.50$\mu$m, indicating the aggregates combine with each other as T increased. By the atomic force microscopy observation, Au nanoparticles with diameter around 45.0 nm were observed in the aggregates, which were independent with T. Similarly, the average height of the aggregates found remain unchanged at around 10.0nm as T increased. The anomalous aggregation mechanism of Au aggregates suggests that a compact microstructure for Au aggregates is preferred at high T rather than three-dimensional (3D) growth, which is quite different from that of Ag aggregates.

For 30 years, silicone oil has been used for the management and rehabilitation of the injured hand. Its benefits accrue from its providing a non-irritant, bland, air-free medium in which the hand can undergo early movement, which prevents drying out of the tissues and helps in the separation of necrotic and infected tissue. It has been reported, however, that the silicone oil might act as a reservoir for nosocomial infection after two patients developed epidemic methicillin-resistant Staphylococcus aureus (EMRSA) infections.

Since no firm guidelines exist with regard to open and/or infected wounds and the continued use of the same oil, a prospective study was set up to study the bacterial colonisation of the silicone oil. Thirty-five consecutive patients were entered into the study. The oil for each patient was changed each week but if any wound became clinically infected the oil was changed earlier. Treatment was continued until the wound was healed or until the treatment was stopped by the referring doctor.

Bacteriology swabs taken from the wound and the oil before each treatment and from the oil after each treatment were analysed for bacterial colonisation. The results indicated that while bacteria were transferred into the oil from the wound, the inoculum was small and had no effect on wound healing. There was no evidence that wounds were being re-infected from the oil. The conclusion was that silicone oil remains a safe medium in which to exercise injured hands.

The present paper focuses on preparation and process of the magnetorheological (MR) fluid whose carrier fluid is silicone-based oil and its additive is the commercial grease with different concentration of iron particles. General properties of MR fluid are discussed and rheological properties like shear rate, shear stress, viscosity of MR fluid can be found by using cone-and-plate sensor system-type rheometer. The result shows that shear stress as a function of magnetic flux density and viscosity does not strictly scale with iron loading.