Because there is industry interest in packaging materials which retain a high degree of transparency while minimising the rate of greening in potato tubers, chlorophyll formation was investigated for 2 cultivars, cv. Rua and cv. Ilam Hardy, using 6 packaging materials and a no packaging treatment. Chlorophyll concentrations were determined after 5, 10, and 15 days of continuous light exposure. Significant differences between the packaging materials tested were noted, and these differences were related to differences in the level of photosynthetically active radiation admitted by the different materials. Differences between packaging materials increased as exposure time increased, and chlorophyll concentrations for cv. Rua were consistently higher than for cv. Ilam Hardy for all packaging materials. Chlorophyll concentration rose with increased exposure time, with that for cv. Rua increasing more rapidly than that for cv. Ilam Hardy. It was concluded that none of the transparent or semi-transparent packaging materials tested offered any improvement over no packaging. All were inferior to the 2 opaque packaging materials tested, with brown paper packaging being most efficient in inhibiting chlorophyll development.

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A Structural Integrity Management (SIM) program plays a substantial role in managing structural risks and reducing expensive deepwater in-situ repairs. Inspection and operating decisions and costs are significantly affected by what is defined in a SIM program. Baldpate compliant tower in particular features an innovative structural system and is among the tallest structures ever built. It is a valuable deepwater asset that needs a SIM program backed by a strong technical foundation to provide confidence that continued service and potentially expanded operations can be safely achieved. Earlier studies had shown that fatigue sensitivities at critical locations could potentially limit Baldpate's useful life beyond the original 20 year target. This was mainly due to the conservatism inherent in the spectral fatigue approach which did not capture the innovative and highly dynamic features of the Baldpate tower. In order to better understand the dynamic characteristics of this unique structure and accurately model the tower, a field measurement campaign using 3D accelerometers was carried out. The measurements were then used to benchmark and adjust the computer model. A time-domain rainflow fatigue analysis was utilized to capture the compliant response of the tower for both fatigue seastates and three large storms which have affected Baldpate. This showed that fatigue sensitivities are not limiting factors for continued service of Baldpate, and the areas of fatigue sensitivity were incorporated into a long term SIM plan to focus future inspection and monitoring efforts. This paper provides details on the study performed for the Baldpate structure using field measurement, a rainflow simulation and its contribution to the development of a long term, risk based SIM plan. The behaviors of several unique structural components, such as stress concentration factors at atypical connections, gap behavior and friction lock-up at the guided axial tubes, were also considered. SIM options for these unique structural components are discussed, including underwater inspection methods and on-site dynamic motion recording. These efforts resulted not only in a more promising range of fatigue lives than previously calculated, but also identified areas of focus in support of a risk based SIM and associated inspection plan to support continued service through the asset's viable economic life. This approach is enhanced by a real-time monitoring plan to measure the dynamic characteristics of the tower under different load conditions to indicate when certain unique structural characteristics (e.g., axial tube motion within the guides) would affect the fatigue life of critical joints in the Baldpate tower.

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