An atmospheric measurement campaign took place in the spring of 2006 to characterize the emission of particles from an integrated iron and steelmaking site. During the measurement campaign, the PM 10 daily limit value of 50 µg m −3 was not exceeded during any day. However, excursions in PM 10 concentrations occurred over periods of a few hours which were associated with wind passing over the steelworks' site. Measurements with an Aerosol Time-ofFlight Mass Spectrometer (ATOFMS) showed six particle classes associated with emissions from steelmaking processes. Two of these were iron-rich, one showing internal mixing with nitrate, the other internally mixed with phosphate, which subsequent analysis identified as arising from the ironmaking sector and the hot and cold mills as the dominant sources, respectively. Other ATOFMS classes were rich in lead, zinc, and nickel, which were also associated with steelmaking sources. A Micro Orifice Uniform Deposit Impactor (MOUDI), used to measure particle size distributions over periods of 19-42 hours, showed two characteristic size distributions for iron, one bimodal with modes at 0.45 µm and 4 µm, the other unimodal centered at 6 µm. In the former case, the smaller mode exhibited a peak for lead at the same particle size and in the case of the larger mode, phosphate and calcium also showed a peak at 4 µm diameter, consistent with the ATOFMS findings. An additional particle type with a unimodal size distribution centered at about 1.2 µm, with internally mixed Pb, Zn, and Cl but not Fe was also found.

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The behaviour of a series of silicone fluids has been examined in the apparatus described in part I. The fluids exhibit non-Newtonian properties and the theory applicable in part I is not able to explain their behaviour. The theory for a power law fluid is developed and shown to be in accord with the experimental results; the experimental observations enable values of the model constants to be deduced.

An apparatus has been constructed to subject a film of oil to high transient stresses and rates of shear by applying an impulsive load. The apparatus makes it possible to derive the values of the instantaneous viscosity of the oil through out the duration of the impact and to detect whether the oil exhibits viscoelastic behaviour in these conditions. Typical mineral lubricating oils do not exhibit elastic properties in the apparatus and their behaviour is explicable on the assumption that the viscosity depends on pressure and temperature in the manner observed in the usual types of viscometer. However, when only elementary calculations are made the viscosity appears to be abnormally low. To explain the behaviour adequately, it is necessary to consider the viscosity of the lubricant not only with respect to temperature and pressure but also from place to place and instant to instant through out the impact. When this is done, the theory provides a good description of the behaviour of the system up to the point at which the pressures cause significant deformation of the plates containing the oil film. Two other oils, each having an initial viscosity and pressure coefficient of viscosity well above the range of typical lubricating oils, have been observed to exhibit anomalous behaviour. The evidence is consistent with the supposition that they behave viscoelastically but further work would be required to prove the point.