43 research outputs found
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Preliminary design review report - sludge offload system
This report documents the conceptual design review of the sludge offload system for the Spent Nuclear Fuel Project. The design description, drawings, available analysis, and safety analysis were reviewed by a peer group. The design review comments and resolutions are documented
Lake sediment fecal and biomass burning biomarkers provide direct evidence for prehistoric human-lit fires in New Zealand
Deforestation associated with the initial settlement of New Zealand is a dramatic example of how humans can alter landscapes through fire. However, evidence linking early human presence and land-cover change is inferential in most continental sites. We employed a multi-proxy approach to reconstruct anthropogenic land use in New Zealand’s South Island over the last millennium using fecal and plant sterols as indicators of human activity and monosaccharide anhydrides, polycyclic aromatic hydrocarbons, charcoal and pollen as tracers of fire and vegetation change in lake-sediment cores. Our data provide a direct record of local human presence in Lake Kirkpatrick and Lake Diamond watersheds at the time of deforestation and a new and stronger case of human agency linked with forest clearance. The first detection of human presence matches charcoal and biomarker evidence for initial burning at c. AD 1350. Sterols decreased shortly after to values suggesting the sporadic presence of people and then rose to unprecedented levels after the European settlement. Our results confirm that initial human arrival in New Zealand was associated with brief and intense burning activities. Testing our approach in a context of well-established fire history provides a new tool for understanding cause-effect relationships in more complex continental reconstructions
Thermal-hydraulic analysis of TFE verification test UFAC-1
The Experimental Breeder Reactor No. II (EBR-II) irradiation test Uninstrumented Fueled Accelerated (UFAC)-1 of seven encapsulated thermionic test pins was analyzed with the code COBRA-SFS. The model predicted coolant and material temperatures for three conditions of interest: steady state full power, response to the unlikely loss of flow transient, and decay heat cooling by forced down flow of argon. Modeling assumptions and a summary of results are included. 1 ref., 12 figs., 3 tabs