Process-based cost modelling for gas induced semi-solid-processed below-knee prosthesis

Below-knee prosthesis is much needed in Thailand and the world over because it serves as a close substitute for a missing body part (e.g. a device to aid people with paraplegia). Production of these components by gas-induced semi-solid process is relatively new, and investors need to be assured of success before committing themselves into a venture. Most cost models, such as the activity-based model, have flexibility limitations, and hence more input-sensitive – the process-based cost model (PBCM) – is alternatively employed in analysing more simple work process, appropriate production volume and unit cost, and was utilised in this research. An array of production volumes (5000–100,000 sets) and a number of daily work shifts (1–3) were investigated. From detailed breakdowns, analysis results suggested an optimal annual production volume in the range of 10,000–40,000 sets employing any shifts per day. Below 10,000, unit cost escalates very sharply, and beyond 40,000 it decreases only marginally. Production for export purposes is feasible since the annual domestic requirement in Thailand is only a fraction of this volume. PBCM had also proven an effective tool in this case.     

TiO2-V2O5 nanocomposites as alternative energy storage substances for photocatalysts

TiO2-V2O5 was prepared and evaluated as an energy storage material for photocatalysts with high capacity and initial charging rate. The compound was successfully obtained by sol-gel technique and effects of compound composition and calcination temperature on the energy storage ability were investigated. The synthesized compounds were characterized by means of X-ray powder diffraction (XRD), scanning electron microscopy equipped with energy-dispersive X-ray analysis (SEM-EDX) and transmission electron microscopy (TEM). The results reveals that the compound of Ti:V molar ratio equal to 1:0.11 calcined at 550 degrees C exhibited superior energy storage ability than parent substances and 1.7-times higher capacity and 2.3-times higher initial charging rate compared to WO3, indicating that the compound is a remarkable alternative to conventional energy storage substances.     

The loss of OSA‐modified starch emulsifier property during the high‐pressure homogeniser and encapsulation of multi‐flavour bergamot oil by spray drying

The encapsulation of bergamot oil by spray drying was investigated by using octenyl succinylated waxy maize starch as wall material and bergamot oil as core. The bergamot oil is majorly composed of d‐limonene, linalool and linalyl acetate. High‐speed and high‐pressure homogenisers were used as major tools of emulsification process. The results indicated that some chemical functional groups were lost during the high‐pressure homogenisation. Moreover, larger emulsion droplet size (5–10 μm) was observed when emulsion passed through high‐pressure homogeniser. Meanwhile, the saturation of carrier solution before preparing the emulsion was also important to produce the encapsulated flavour powder by spray drying. The optimal value of air inlet temperature at 160 °C to give the highest flavour retention and the lowest surface oil content was observed. Furthermore, the retention of linalool after spray drying was higher than 100%. The transformation of each flavour might occur.     

Mechanical Properties of High Density Polyethylene/Modified Calcium Silicate Composites

High density polyethylene (HDPE)/calcium silicate (CS) composites containing vinyltriethoxysilane treated calcium silicate contents varying from 0–10 phr were prepared by injection molding. Thus obtained HDPE/CS composites were characterized by the thermal analyses. The mechanical properties were evaluated. It was found that the incorporation of the calcium silicate into high density polyethylene resulted in a slight increase in the yield stress (6.85–11.76 %) as well as tensile strength (7.02–12.84 %). However, the elongation at yield and the elongation at break decreased by 9.23–24.87 % and by 11.03–60.73 %, respectively, with the increasing calcium silicate content. The vinyltriethoxysilane modified CS exhibited the dispersibility in HDPE matrix arising from the compatibility between high density polyethylene matrix and the disperse phase (treated calcium silicate particles) which led to the effect on the mechanical properties of the composites. It could be concluded that the modified calcium silicate played a role in reinforcing the mechanical properties into the high density polyethylene.