• Fibers and Polymers
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• v.2 no.1
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• pp.144-147
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• 2001

The HVI properites and Mantis single fiber tensile properties were analyzed to evaluate the relationship between fiber and bundle tensile properties. For this study, a new method has been developed for estimating the modulus and toughness of cotton fiber bundles directly from the HVI tenacity-elongation curves. The single fiber tensile properties were shown to be translated well into the bundle tensile properties. The single fiber breaking elongation was found to be the most significant contributing factor to bundle tensile properties. The bundle breaking elongation and toughness were shown to increase as the single fiber breaking elongation increased. The bundle modulus increased as the single fiber breaking elongation and/or standard deviation of single fiber breaking elongation decreased.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.11
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• pp.2305-2311
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• 2002

The pressure tube is a major component of the CANDU reactor, which supports nuclear fuel bundle and heavy water coolant. Pressure tubes are installed horizontally inside the reactor and only selected samples are periodically examined during in-service inspection. In this respect, a probabilistic safety assessment method is more appropriate fur the assessment of overall pressure tube safety. The failure behavior of CANDU pressure tubes, however, is governed by delayed hydride cracking which is the major difference from pipings and reactor pressure vessels. Since the delayed hydride cracking has more widely distributed governing parameters, it is impossible to apply a general PFM methodology directly. In this paper, a PFM methodology for the safety assessment of CANDU pressure tubes is introduced by applying Monte Carlo simulation in determining failure probability Initial hydrogen concentration, flaw shape and depth, axial and radial crack growth rate and fracture toughness were considered as probabilistic variables. Parametric study has been done under the base of pressure tube dimension and hydride precipitation temperature in calculating failure probability. Unstable fracture and plastic collapse are used for the failure assessment. The estimated failure probability showed about three-order difference with changing dimensions of pressure tube.

• Journal of Marine Bioscience and Biotechnology
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• v.6 no.2
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• pp.41-46
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• 2014

Mussel byssus is a bundle of threads used to attach mussels to wet substrates. Recently, a thin cuticle layer on the byssus has attracted public attentions due to its remarkable toughness - stiff as epoxy resin and extensible as rubber. Here, we observed ultrastructure of the cuticle layer in a far eastern mussel (Mytilus coruscus) to understand underlying mechanisms for the mechanical properties. The cuticle layer observed by TEM was composed of submicron-sized granular inclusions in a continuous matrix phase. In addition, ultrastructural study in the presence of tertiary amine (Tetraethylammonium, TEA) showed an evidence that the cuticle is stabilized by cation-${\pi}$ interaction.