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A novel high-density yeast propagation system has been developed, which produced yeast that performed as well as cropped yeast in commercial brewery trials. This process is capable of producing yeast concentrations 13 times greater than traditional yeast propagation approaches used in breweries to date. The system is based on a controlled fed-batch yeast fermentation, which can produce pitching yeast in as little as 24h. A demonstrator plant was installed in a regional brewery and yeast produced from the test-platform was used to pitch commercial brews. Plant-scale trials have shown that the yeast propagated using this new system had the same fermentation profile compared to control fermentations that used cropped yeast. Volatile analysis showed no significant difference between the control and experimental beers. The experimental beers tasted true-to-type and were released to trade. The new process allows for smaller pitching volumes while maintaining overall beer quality.

The field of planar chromatography has seen a resurgence due to interest in novel fabrication techniques for sorbent (stationary phase) layers. These novel sorbents must have high surface areas and achieve separations over short distances. Here, we present the first attempt to fabricate a planar chromatographic platform via laser ablation. Microchannels of 24 mm µm x 68 mm depth were produced using an Nd:YAG laser on cyclic olefin polymer substrates which act as the stationary phase. These plates were then applied to a proof-of-concept organic dye separation and were able to resolve a binary dye mixture over 11 mm of plate length. Results showed promising potential for laser ablation as a new fabrication technique for planar chromatographic substrates.

As nanomaterials find applications in an increasingly diverse range of fields such as wastewater treatment, biotechnology and flexible electronics, the demand for nanomaterials with specific proper...

Electroless coatings (unary, binary and ternary) are utilised nowadays on a wide scale due to their good tribological and mechanical properties (anti-wear, friction, hardness, anti-corrosion).In re...

On inception, 3D printed parts were typically used at prototyping stage to give the end user/customer a real world concept of how the part may appear when traditional manufacturing techniques were ...

With advances in additive manufacturing, particularly in the area of three dimensional (3D) printing, it is becoming possible to generate small quantities of functional components. As with all manu...

In this paper, the preparation and properties of reduced graphene oxide (rGO) reinforcement of aluminium matrix nanocomposites (AMCs) are presented. The commercial colloidal graphene oxide was firstly coated on the selected aluminium powder particles, and the graphene oxide was then reduced through thermal annealing process. The rGO-aluminium powder dispersions were prepared in order to provide coated aluminium particles before synthesis of the metal matrix nanocomposites. As-received pristine aluminium powder and pre-synthesised rGO-AMCs were cold compacted into disc-shaped specimens and sintered. The mechanical properties and microstructure were studied and characterised via Vickers hardness, a flexural bending test, X-ray diffraction and scanning electron microscopy. The rGO was observed to be dispersed effectively in the aluminium matrix and well consolidated within the composites. The relevant factors for the powder metallurgy process, e.g. compaction pressure, density, sintering conditions, ...

The microstructure of high-temperature metals such as Ti, Ni, and Cr can be modified using ceramic nanoparticles to form metal matrix nanocomposites (MMNCs). Such materials are generally prepared via powder metallurgy routes. In this study, 25 wt% SiCnp and Al2O3np were separately ball milled as a reinforcement of Ti, Cr, and Ni matrices to investigate their effects on the phase formation and morphology of the MMNCs. The x-ray diffraction (XRD), scanning electron microscopy (SEM), and field emission scanning electron microscopy (FESEM) results indicated that the alumina–metal system could not be thermodynamically stable in a high-energy ball mill, while the SiC reinforcement could be retained and milled with the metals even after 24 h. It was further observed that the distribution of nanoparticles was not affected by the type of metal, ceramic, and milling time. Finally, it was determined that the nanoparticles significantly reduced the average particle size of composite powders.

In this study, two kinds of micrometre sized SiC powders (as received and ball milled) were used as the starting materials to investigate the effect of ceramic surface morphology on the coating characteristics. Determined optimised electroless deposition bath values of pH (9) and bath temperature (70°C) were used. It was found that etching pretreatment was very effective on the coating quality for both types of SiC powders. The experimental results indicated that milling of the powders led to the formation of multimodal sized ceramic powders with sharp edges and rough surfaces, which resulted in a uniform adhesive metallic layer on the powders without any crack formation. Finally, the effect of cobalt coating on the incorporation of ceramic particles into the molten aluminium during fabrication of aluminium matrix composite was studied, and it was revealed that a significant improvement in incorporation could be obtained using cobalt coated ceramic particles.

A new low-cost process for fast fabrication of multilayer microfluidic devices using cyclic olefin copolymer film materials is presented. This novel process consists of the fabrication of microfluidic features by xurography, followed by multilayer lamination via cyclohexane vapor exposure. Exposure time to this solvent and compression time were optimized for bond tensile strength. A three-layer microfluidic chip capable of withstanding back pressures up to 23 MPa was fabricated in less than an hour. The suitability of this fast prototyping method for fabrication of functional UV-transparent microfluidic devices was demonstrated by development and testing of a microfluidic mixer and preparation of a polymer monolithic column within the microfluidic channel.

Semisolid metal processing (SSMP) is of growing industrial significance particularly for magnesium and aluminium alloys. SSMP requires a binary micro-structure in which the primary phase is approac...