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The purpose of this paper was to examine the rheological characterisation of thickened water under different temperature and pH conditions and thickened milk with different fat contents.

Beverages thickened with powdered thickeners are used in the medical management of individuals who suffer swallowing difficulties (dysphagia). Each individual requires a specific level of thickness to best meet the needs of their dysphagia. Although the level of thickness is defined, obtaining the correct consistency of thickened fluids is difficult. This is due to fluctuations associated with temperature and type of fluids to be thickened. Rheological characterisation of commercially available xanthan gum-based thickener was performed under different conditions of temperature, pH and fat contents.

The viscosity and the yield stress of thickened water was found to be unaffected by pH. Similarly, temperature did not affect the viscosity at a high thickener concentration, although it did at lower concentration levels. Conversely, viscosity and yield stress increased as fat levels increased in thickened milk. Furthermore, thickened water took less than 2 minutes to reach equilibrium viscosity, while thickened milk required approximately 15 minutes to reach equilibrium viscosity.

These findings have implications for the standing time required for different beverages before they are thickened to a consistency that has been deemed safe for the patient’s physiological needs. Additionally, it highlights that different liquid base substances required different amounts of thickener to achieve the same level of thickness.

Findings from this study confirms and explores the variability of thickened fluids under different conditions of temperature, pH and fat content for the medical management of dysphagia.

The paper seeks to find out new eco‐environmentally friendly surface treatments based on vanadate compounds as alternatives to the process involving toxic chromates for the corrosion protection of aluminium alloys.

A treatment process in which the surface was etched prior to vanadia treatment is being proposed. The process involves cleaning, etching in potassium hydroxide followed by treatment in vanadia prepared by sol‐gel method. The effect of surface preparation prior to vanadia treatment on the corrosion resistance of AA6061 T6 in 3.5 per cent NaCl solution was measured using AC impedance spectroscopy and DC polarization techniques. Surface examination was performed by scanning electron microscopy (SEM), energy dispersive X‐ray (EDS), X‐ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM).

It has been shown that the etching process prior to vanadia treatment enhanced formation of a uniformly distributed compact surface V‐rich Al‐oxide film of smooth appearance and inhibited the active surface sites and thereby preventing localized corrosion.

Vanadate conversion coatings seem very promising as alternatives to toxic chromating for the corrosion protection of aluminium alloys in NaCl solution.

In treating both sewage and storm runoff, wastewater treatment plants are important to maintaining a healthy environment. If the plant operations managers do not respond correctly to plant conditions, environmental damage resulting in the deterioration of human health may be the result. Unfortunately, there are no formal models to help these managers; they rely upon their own intuition to manage the plants. The purpose of this paper is to investigate the effectiveness of various models, originally used for manufacturing, to detect process conditions in wastewater treatment facilities. We compare and contrast the performance of five statistical models and three neural network architectures. The data used in the research is 527 daily measurements of 38 sensor readings of the process state variables of an urban wastewater treatment plant.

In addition to acting as thickeners in lubricating greases metal soaps play an important role as additives in a wide range of other industries. Some of their typical properties are:

I.C. Engine Lubricating System. Farbwerke Hoechst Aktiengesellschaft, vormals Meister Lucius & Bruning, Frankfurt. Spec. No. 1,266,607.

Flash rusting and corrosion undercutting of water‐thinned paint films on iron surfaces are caused by the electrochemical decomposition of that steel surface. Flash rusting is that rust‐coloured spotting which occurs as the iron is solubilized and bleeds through that water‐thinned paint film. The steel simply corrodes because of the flow of electric currents that occur as the pure iron reverts to its more stable compounds: ferric hydroxide, hydrated ferric oxides and ferric oxides. This paper reviews the chemistry of flash rusting and corrosion undercutting and reports on the successful applications of modified barium metaborate in providing both initial and long‐term corrosion resistance for water‐thinned paints on steel. Several physical factors that contribute to flash rusting and corrosion undercutting are also discussed.

To develop new eco‐environmentally friendly surface treatments based on cerate compounds as alternatives to the process involving toxic chromates for the corrosion protection of magnesium alloys.

A treatment process in which a surface was alkaline‐etched prior to ceria treatment is proposed. The process involves cleaning, etching in potassium hydroxide followed by treatment in ceria conversion coatings. The effect of surface preparation prior to ceria treatment on the corrosion resistance of AZ91D in 3.5 per cent NaCl solution was measured using AC impedance spectroscopy and DC polarization techniques. Surface examination was performed by scanning electron microscopy, energy dispersive X‐ray.

It was shown that the ceria treatment can be used as a localized corrosion inhibitor for alloy AZ91D in NaCl solution. The level of inhibition strongly depended on the cerium concentration. Moreover, ceria treatments improved the pitting corrosion resistance due to the formation of protective oxide films which act as a barrier to oxygen diffusion to the metal surface. According to the EIS and polarization measurements, alkaline etching in KOH is more effective in reducing the pitting corrosion of AZ91D than was HCl. It was shown that surface treatment in alkaline solution (KOH) prior to ceria treatments played an important role in inhibiting the active surface sites, rejecting the chloride ions from the surface and forming uniformly distributed oxide film.

Ceria conversion coatings seem very promising as alternatives to toxic chromating for the corrosion protection of magnesium alloys in NaCl solution.

The first article of this series referred to the problems and difficulties peculiar to aircraft lubrication because of the wide temperature range to which aircraft lubricants are subjected. An engine lubricant works only for a very short time at sub‐zero temperatures, and spends most of its working life at around 100°C. (212°F.). The converse is true of most airframe lubricants—they spend much of their working life at very low temperatures and only occasionally reach the higher levels. Continuous efficient lubrication at very low temperatures must therefore be provided.

In the last 25 years, we have seen a considerable increase in the use of new and unconventional methods for the remedial treatment of building defects. Some of the materials and techniques used have been employed long enough for an assessment to be made of their efficacy based on field experience. Some have only been evaluated by accelerated laboratory methods and do not yet have the full support of service records. Other products are declining in importance as a result of a ‘lack of approval’ by the independent bodies that pronounce on these matters.

The Lubrizol Corporation has been implementing a policy of moving its technology closer to the customer. The aim has been to achieve faster product development response times to maintain its position as market leader in an increasingly competitive business. The company's European marketing and technology centre at Hazelwood, near Derby, has benefited by being upgraded and expanded over the past five years from essentially an engine testing and technical service centre to an establishment that includes two of the major formulation groups. This will give Hazelwood greater flexibility in tailoring additives to suit European needs, a market which accounted for almost one‐third of Lubrizol's worldwide sales in 1991.