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Wind turbines are subject to a wide range of environmental conditions during a lifespan that can conceivably extend beyond 20 years. Hailstone impact is thought to be a key factor in the leading edge erosion and damage of wind turbine blades. Along with the size and density of the hailstone, the aggregated impact velocity components are crucial variables that characterise the kinetic energy associated with singular impact. These components include: the terminal velocity of the hailstone, the mean wind speed and the rotational speed of the turbine. Theorised values for the impact velocity may not truly reflect the conditions experienced by wind turbine blades. Using UK meteorological data, a greater representation of hail characteristics, occurrence probabilities and realistic impact component velocities is proposed, which will assist in the development of a realistic damage model for hailstone impact.

An attempt has been made to study the effect of bio-oils on the two- and three-body abrasion process of pure metals and steel. The equipment used was a micro-abrasion tester (TE-66, Phoenix Tribology (Plint)). The materials considered were mild steel, copper, and aluminium, being the most usable and basic materials for industrial applications such as bearings and gear assemblies. The results were used to identify transitions between wear regimes as a function of sliding speed and load. The effect on the abrasion process in the presence of various lubricant oils was also assessed. The mechanisms of abrasion with and without particles were characterised.

The flow-induced corrosion of iron, in spent Bayer liquor at high temperatures, was investigated using a rotating cylinder electrode (RCE) in an autoclave facility. A temperature range of 100 degreesC to 230 degreesC and equivalent pipe velocities between 0.84 ms(-1) to 3 ms(-1) were used in this work. Techniques, such as, weight loss, ac impedance, potential measurements and electron microscopy were used to characterise corrosion behaviour during the experiments and also any surface corrosion products formed. Corrosion rates measured by weight loss were in good agreement with those obtained through ac impedance measurements. The results showed evidence of a peak in the corrosion rate with increasing temperature for iron. Such peaks were also observed as a function of increasing velocity. The effects of these variables were demonstrated by constructing a corrosion map in which regions of "high", "medium" and "low" corrosion rate for the material, under specific conditions, were identified. This method may be a useful way of providing a guide to optimise the process conditions when using materials in high temperature alkaline flowing environments such as those found in Bayer plants.

An observational approach is recommended in newly diagnosed children with immune thrombocytopenia (ITP) at low risk of bleeding; however, there is no standard definition of risk. A standardized clinical assessment and management plan (SCAMP® ), a modifiable practice guideline, was implemented and revised (SCAMP-1 and SCAMP-2) and applied to 71 newly diagnosed patients with ITP. The Buchanan and Adix bleeding score guided treatment and was modified by stratifying by low- and high-risk grade 3 bleeding in SCAMP-2. Observation rates increased from 40% to 74% from SCAMP-1 to SCAMP-2 (P < 0.05) with no bleeding complications. We propose a modified bleeding score that increased observation rates in low-risk patients with ITP.

Although there have been many studies of erosion-corrosion of alloys involving impact by solid particles in air or oxygen at high temperatures, there have been very few, if any, in gases of high-sulphur, low-oxygen activities. As these environments are pertinent in processes such as coal gasification and catalytic cracking of oil, there is a need for some basic studies of the interactions of erosion and corrosion in oxidizing/sulphidizing gases. Thus, a whirling-arm rig has been designed and constructed; it can operate under a range of erosion conditions (velocities to 30 m s(-1), particles fluxes to 1 g m(-2) s(-1)) in gaseous environments consisting of mixtures of nitrogen, hydrogen, hydrogen sulphide and water vapour as necessary, at temperatures to 800 degrees C. Some preliminary tests have been carried out using 310 stainless steel and Alloy 800HT at 500 and 700 degrees C and Fe-2.25Cr-1Mo and 410 stainless steel at 500 degrees C. Erosion particles were 25 mu m alumina, with impact velocities of 10 to 25 m s(-1) and fluxes of 0.06 to 0.16 g cm(-2) s(-1). The gaseous environment was a mixture of hydrogen, hydrogen sulphide and nitrogen; this caused sulphidation of all the alloys at both temperatures. The extents of erosion-corrosion damage were determined by thickness-change measurements taken every 5 h and overall metal-recession measurements taken at the end of the full test period of 35 h. The extents of damage were increased significantly with increasing impact velocity for the austenitic alloys at 700 degrees C; similar trends were observed at 500 degrees C for Fe-2.25Cr-1Mo and 410 stainless steel, although the presence of impacting particles had only a small effect on the austenitic alloys at the lower temperature. These initial results are discussed in terms of the interactions of growth of the sulphide scale and removal of scale by the particles.

A Rotating Cylinder Electrode (RCE) system has been used to determine the corrosion kinetics of mild steel in the active dissolution potential range under erosion-corrosion conditions. The hydrodynamics of the rotating cylinder electrode were characterized by the mass transfer controlled oxygen reduction reaction on a copper electrode. The anodic dissolution current was measured at various potentials and velocities in de-aerated 0.5M NaHCO3 + 0.5M Na2CO3 solution, with or without the addition of 300 g/l of 100 mu m alumina. The results show that anodic dissolution processes in this system are under mass transfer control in turbulent flow conditions. The anodic dissolution rate increases significantly with the introduction of particles, owing to an increase of mass transfer coefficient and removal of corrosion deposits on the electrode surface.