1,259 research outputs found
A Novel Approach to Spent Fuel Pool Decommissioning
The Idaho National Laboratory (INL) has been at the forefront of developing methods to reduce the cost and schedule of deactivating spent fuel pools (SFP). Several pools have been deactivated at the INL using an underwater approach with divers. These projects provided a basis for the INL cooperation with the Dresden Nuclear Power Station Unit 1 SFP (Exelon Generation Company) deactivation. It represents the first time that a commercial nuclear power plant (NPP) SFP was decommissioned using this underwater coating process. This approach has advantages in many aspects, particularly in reducing airborne contamination and allowing safer, more cost effective deactivation. The INL pioneered underwater coating process was used to decommission three SFPs with a total combined pool volume of over 900,000 gallons. INL provided engineering support and shared project plans to successfully initiate the Dresden project. This report outlines the steps taken by INL and Exelon to decommission SFPs using the underwater coating process. The rationale used to select the underwater coating process and the advantages and disadvantages are described. Special circumstances are also discussed, such as the use of a remotely-operated underwater vehicle to visually and radiologically map the pool areas that were not readily accessible. A larger project, the INTEC-603 SFP in-situ (grouting) deactivation, is reviewed. Several specific areas where special equipment was employed are discussed and a Lessons Learned evaluation is included
Addition of a dairy fraction rich in milk fat globule membrane to a high-saturated fat meal reduces the postprandial insulinaemic and inflammatory response in overweight and obese adults.
Meals high in SFA, particularly palmitate, are associated with postprandial inflammation and insulin resistance. Milk fat globule membrane (MFGM) has anti-inflammatory properties that may attenuate the negative effects of SFA-rich meals. Our objective was to examine the postprandial metabolic and inflammatory response to a high-fat meal composed of palm oil (PO) compared with PO with an added dairy fraction rich in MFGM (PO+MFGM) in overweight and obese men and women (n 36) in a randomised, double-blinded, cross-over trial. Participants consumed two isoenergetic high-fat meals composed of a smoothie enriched with PO with v. without a cream-derived complex milk lipid fraction ( dairy fraction rich in MFGM) separated by a washout of 1-2 weeks. Serum cytokines, adhesion molecules, cortisol and markers of inflammation were measured at fasting, and at 1, 3 and 6 h postprandially. Glucose, insulin and lipid profiles were analysed in plasma. Consumption of the PO + MFGM v. PO meal resulted in lower total cholesterol (P = 0·021), LDL-cholesterol (P = 0·046), soluble intracellular adhesion molecule (P = 0·005) and insulin (P = 0·005) incremental AUC, and increased IL-10 (P = 0·013). Individuals with high baseline C-reactive protein (CRP) concentrations (≥3 mg/l, n 17) had higher (P = 0·030) insulin at 1 h after the PO meal than individuals with CRP concentrations <3 mg/l (n 19). The addition of MFGM attenuated this difference between CRP groups. The addition of a dairy fraction rich in MFGM attenuated the negative effects of a high-SFA meal by reducing postprandial cholesterol, inflammatory markers and insulin response in overweight and obese individuals, particularly in those with elevated CRP
Towards the decontamination of plutonium contaminated bricks:Creation of a cerium-based simulant contamination system
There is a need for the decontamination of a number of plutonium-contaminated bricks encountered in a legacy BUTEX reprocessing plant on Sellafield site in the UK. Documentary review has indicated that the source of the contamination was a 8 mol dm -3 nitric acid process stream containing 10 mmol dm -3 of Pu in either the (III) or (IV) oxidation state. Here we have sought to emulate the behaviour of Pu(III) by treatment of fired clay brick surfaces with a solution of 10 mmol dm -3 Ce(III) nitrate in 8 mol dm -3 nitric acid. XRD, porosimetry and EDX measurements of the untreated bricks reveal them to be comprised of low porosity silica and aluminosilicate phases with a surface layer of a low-Si content Al-C-N oxide derived from the atmosphere of the kiln in which the bricks were fired. Depth profiling after an initial 6 week acid soak reveals that the acid penetrates <10 mm into the brick. SEM/EDX analysis reveals that acid treatment significantly roughens the brick surface due to dissolution the above described Al-C-N oxide layer. The EDX data also shows that virtually no Ce is retained as tenacious contamination at the brick surface; this may be due to a either a mass action/kinetic effect or taken to indicate that trivalent Ce(III) is less likely to absorb at the crystalline silica/aluminosilicate surface of the brick than its more easily hydrolysable tetravalent equivalent. Preliminary higher-resolution EDX analysis indicates that small quantities of Ce(III) can be detected in pores or cracks on the surface of acid-treated brick samples. This suggests that Ce(III) may be non-tenaciously sequestered into surface defects - and that a simple salt wash may be sufficient to remove it. Based on the above observations, potential decontamination strategies are discussed and future studies outlined
Consumption of a high-fat meal containing cheese compared with a vegan alternative lowers postprandial C-reactive protein in overweight and obese individuals with metabolic abnormalities: a randomised controlled cross-over study.
Dietary recommendations suggest decreased consumption of SFA to minimise CVD risk; however, not all foods rich in SFA are equivalent. To evaluate the effects of SFA in a dairy food matrix, as Cheddar cheese, v. SFA from a vegan-alternative test meal on postprandial inflammatory markers, a randomised controlled cross-over trial was conducted in twenty overweight or obese adults with metabolic abnormalities. Individuals consumed two isoenergetic high-fat mixed meals separated by a 1- to 2-week washout period. Serum was collected at baseline, and at 1, 3 and 6 h postprandially and analysed for inflammatory markers (IL-6, IL-8, IL-10, IL-17, IL-18, TNFα, monocyte chemotactic protein-1 (MCP-1)), acute-phase proteins C-reactive protein (CRP) and serum amyloid-A (SAA), cellular adhesion molecules and blood lipids, glucose and insulin. Following both high-fat test meals, postprandial TAG concentrations rose steadily (P < 0·05) without a decrease by 6 h. The incremental AUC (iAUC) for CRP was significantly lower (P < 0·05) in response to the cheese compared with the vegan-alternative test meal. A treatment effect was not observed for any other inflammatory markers; however, for both test meals, multiple markers significantly changed from baseline over the 6 h postprandial period (IL-6, IL-8, IL-18, TNFα, MCP-1, SAA). Saturated fat in the form of a cheese matrix reduced the iAUC for CRP compared with a vegan-alternative test meal during the postprandial 6 h period. The study is registered at clinicaltrials.gov under NCT01803633
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EBR-II Primary Tank Wash-Water Alternatives Evaluation
The EBR-II reactor at Idaho National Laboratory was a liquid sodium metal cooled reactor that operated for 30 years. It was shut down in 1994; the fuel was removed by 1996; and the bulk of sodium metal coolant was removed from the reactor by 2001. Approximately 1100 kg of residual sodium remained in the primary system after draining the bulk sodium. To stabilize the remaining sodium, both the primary and secondary systems were treated with a purge of moist carbon dioxide. Most of the residual sodium reacted with the carbon dioxide and water vapor to form a passivation layer of primarily sodium bicarbonate. The passivation treatment was stopped in 2005 and the primary system is maintained under a blanket of dry carbon dioxide. Approximately 670 kg of sodium metal remains in the primary system in locations that were inaccessible to passivation treatment or in pools of sodium that were too deep for complete penetration of the passivation treatment. The EBR-II reactor was permitted by the Idaho Department of Environmental Quality (DEQ) in 2002 under a RCRA permit that requires removal of all remaining sodium in the primary and secondary systems by 2022. The proposed baseline closure method would remove the large components from the primary tank, fill the primary system with water, react the remaining sodium with the water and dissolve the reaction products in the wash water. This method would generate a minimum of 100,000 gallons of caustic, liquid, low level radioactive, hazardous waste water that must be disposed of in a permitted facility. On February 19-20, 2008, a workshop was held in Idaho Falls, Idaho, to look at alternatives that could meet the RCRA permit clean closure requirements and minimize the quantity of hazardous waste generated by the cleanup process. The workshop convened a panel of national and international sodium cleanup specialists, subject matter experts from the INL, and the EBR-II Wash Water Project team that organized the workshop. The workshop was conducted by a trained facilitator using Value Engineering techniques to elicit the most technically sound solutions from the workshop participants. The path forward includes developing the OBA into a well engineered solution for achieving RCRA clean closure of the EBR-II Primary Reactor Tank system. Several high level tasks are also part of the path forward such as reassigning responsibility of the cleanup project to a dedicated project team that is funded by the DOE Office of Environmental Management, and making it a priority so that adequate funding is available to complete the project. Based on the experience of the sodium cleanup specialists, negotiations with the DEQ will be necessary to determine a risk-based de minimus quantity for acceptable amount of sodium that can be left in the reactor systems after cleanup has been completed
Periodontal Status and A1C Change: Longitudinal results from the Study of Health in Pomerania (SHIP)
Autoimmune optic neuritis in the common marmoset monkey: comparison of visual evoked potentials with MRI and histopathology.
Evaluating clinical periodontal measures as surrogates for bacterial exposure: The Oral Infections and Vascular Disease Epidemiology Study (INVEST)
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Laboratory Evaluation of Underwater Grouting of CPP-603 Basins
A project is underway to deactivate a Fuel Storage Basin. The project specifies the requirements and identifies the tasks that will be performed for deactivation of the CPP- 603 building at the Idaho Nuclear Technology and Engineering Center of the Idaho National Engineering and Environmental Laboratory. The Fuel Receiving and Storage Building (CPP- 603) was originally used to receive and store spent nuclear fuel from various facilities. The area to undergo deactivation includes the three spent nuclear fuel storage basins and a transfer canal (1.5 million gallons of water storage). Deactivation operations at the task site include management of the hot storage boxes and generic fuel objects, removal of the fuel storage racks, basin sludge, water evaporation and basin grouting, and interior equipment, tanks, and associated components. This includes a study to develop a grout formulation and placement process for this deactivation project. Water will be allowed to passively evaporate to r educe the spread of contamination from the walls of the basin. The basins will be filled with grout, underwater, as the water evaporates to maintain the basin water at a safe level. The objective of the deactivation project is to eliminate potential exposure to hazardous and radioactive materials and eliminate potential safety hazards associated with the CPP-603 building
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