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Magnesium potassium phosphate cements (MKPC) were investigated to determine their efficacy towards retardation of reactive uranium metal corrosion. Optimised low-water content, fly ash (FA) and blast furnace slag (BFS) blended MKPC formulations were developed and their fluidity, hydration behaviour, strength and phase assemblage investigated. In-situ time resolved synchrotron powder X-ray diffraction was used to detail the early age (~60 h) phase assemblage development and hydration kinetics, where the inclusion of BFS was observed to delay the formation of struvite-K by ~14 h compared to FA addition (~2 h). All samples set within this period, suggesting the possible formation of a poorly crystalline binding phase prior to struvite-K crystallisation. Long-term corrosion trials using metallic uranium indicated that MKPC systems are capable of limiting uranium corrosion rates (reduced by half), when compared to a UK nuclear industry grout, which highlights their potential application radioactive waste immobilisation.

The identification of preferred binding domains within a host structure provides important insights into the function of materials. State-of-the-art reports mostly focus on crystallographic studies of empty and single component guest-loaded host structures to determine the location of guests. However, measurements of material properties (e.g., adsorption and breakthrough of substrates) are usually performed for a wide range of pressure (guest coverage) and/or using multi-component gas mixtures. Here we report the development of a multifunctional gas dosing system for use in X-ray powder diffraction studies on Beamline I11 at Diamond Light Source. This facility is fully automated and enables in situ crystallographic studies of host structures under (i) unlimited target gas loadings and (ii) loading of multi-component gas mixtures. A proof-of-concept study was conducted on a hydroxyl-decorated porous material MFM-300(V-III) under (i) five different CO2 pressures covering the isotherm range and (ii) the loading of equimolar mixtures of CO2/N-2. The study has successfully captured the structural dynamics underpinning CO2 uptake as a function of surface coverage. Moreover, MFM-300(V-III) was incorporated in a mixed matrix membrane (MMM) with PIM-1 in order to evaluate the CO2/N-2 separation potential of this material. Gas permeation measurements on the MMM show a great improvement over the bare PIM-1 polymer for CO2/N-2 separation based on the ideal selectivity.

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End of Project Report Teagasc acknowledges with gratitude grant aid under the EU Framework Programme (EU FAIR contract No. CT-95-0085). The nutritional benefits of fish oils are generally attributed to their content of long chain omega-3 polyunsaturated fatty acids (PUFAs). Diets rich in these fatty acids are known to reduce the risk of coronary thrombosis, and are recommended to those who are susceptible to atherosclerosis. In addition, some of these long chain PUFAs play an important role in early infant nutrition, in the development of vital human organs such as the neural tube. However, practical difficulties arise in achieving an adequate daily intake of fish oils to obtain these physiological benefits. Per capita fish consumption is low in many countries, especially of oily fish with high levels of omega-3 PUFAs. Fish oil, while available as a dietary supplement, is not universally appealing in that form. Attempts to incorporate fish oil into food formulations have had limited success mainly because of fishy flavours coming through in the consumer products. Fish oil is particularly susceptible to oxidation, which results in fishy, painty and metallic flavours. Hence the main aim of this study was the development of a dried ingredient in which the formulation and related processing conditions were optimised to protect the fish oil from oxidation. Protection of any sensitive oil may be achieved by means of microencapsulation, whereby oil is dispersed as very fine droplets in emulsions. During subsequent spray drying the droplets are effectively sealed inside a protective coating of protein surrounded by carbohydrate. The objective was, therefore, to evaluate microencapsulation as a means of extending the shelf-life of fish oil in powder form thus increasing its versatility as a nutritional ingredient in food formulations. European Union

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