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The effective elastic properties of carbon fibre reinforced silicon carbide composite (C/SiC) with multilayered matrix manufactured by chemical vapour infiltration method are studied in the present paper. Based on the material tomography of scanning electron microscopy, distributions of voids and microcracks are identified and taken into account in the finite element model of such C/SiC composite. It is shown the proposed two scale finite element models of multilayered C/SiC composites can characterise physically the real situation of involved voids and microcracks related to the chemical vapour infiltration process. The numerical results of effective moduli and experimental ones have a reasonable agreement. [ABSTRACT FROM AUTHOR]

The bottom up multiscale finite element modelling that is based on the sequential consideration of the fibre/interface/matrix scale and the tow/matrix/coat scale is employed to predict the effective elastic modulus of the plain wave multiphase and multilayer silicon carbide ceramic matrix composite. Instead of using the homogenisation method, the strain energy based method that is advantageous in computing efficiency and numerical implementation is adopted for the multiscale analysis and evaluation of effective properties. First, the effective properties of tows are computed on the fibre/interface/matrix scale. They are then incorporated into the tow/matrix/coat scale to evaluate the effective properties of the composite. Numerical results obtained by the proposed method and model show a good agreement with the results measured experimentally. [ABSTRACT FROM AUTHOR]

Nanostructured silver films were deposited at room temperature on polypropylene non-wovens by radio frequency magnetron sputter coating to obtain the antibacterial properties, and the relationship between sputter parameters and antibacterial properties were investigated in this paper. The antibacterial activity of the materials was assessed using shake flask test. The effects of silver film deposition on surface morphology were characterised using SEM and AFM. Surface elemental compositions were also analysed using EDX analysis. The results of antibacterial tests revealed that deposition time was the key parameter affecting the antibacterial properties of the materials, while sputtering power and argon pressure seemed to have a slight effect on antibacterial performance. It is believed that the total amount of silver ions released from the silver coating was increased as the deposition time increased. The AFM images and quantitative analysis by EDX respectively revealed that increase in deposition time led to the increased coverage of silver film and the increased silver weight percentage per unit surface, which provided evidences for the increased release rate of the silver ions from coating. [ABSTRACT FROM AUTHOR]

A 2-day-old, female infant underwent total gastrectomy for spontaneous gastric gangrene and perforation. She developed the following complications: growth retardation, vitamin B12 deficiency, post-gastrectomy dumping syndrome, and occasional bile regurgitation. Nutritional management is described The two previously reported survivors of total gastrectomy in the neonatal period are reviewed. [ABSTRACT FROM AUTHOR]