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Idaho National Laboratory Lead or Lead-Bismuth Eutectic (LBE) Test Facility - R&D Requirements, Design Criteria, Design Concept, and Concept Guidance
The Idaho National Laboratory Lead-Bismuth Eutectic Test Facility will advance the state of nuclear technology relative to heavy-metal coolants (primarily Pb and Pb-Bi), thereby allowing the U.S. to maintain the pre-eminent position in overseas markets and a future domestic market. The end results will be a better qualitative understanding and quantitative measure of the thermal physics and chemistry conditions in the molten metal systems for varied flow conditions (single and multiphase), flow regime transitions, heat input methods, pumping requirements for varied conditions and geometries, and corrosion performance. Furthering INL knowledge in these areas is crucial to sustaining a competitive global position. This fundamental heavy-metal research supports the National Energy Policy Development Group’s stated need for energy systems to support electrical generation.1 The project will also assist the Department of Energy in achieving goals outlined in the Nuclear Energy Research Advisory Committee Long Term Nuclear Technology Research and Development Plan,2 the Generation IV Roadmap for Lead Fast Reactor development, and Advanced Fuel Cycle Initiative research and development. This multi-unit Lead-Bismuth Eutectic Test Facility with its flexible and reconfigurable apparatus will maintain and extend the U.S. nuclear knowledge base, while educating young scientists and engineers. The uniqueness of the Lead-Bismuth Eutectic Test Facility is its integrated Pool Unit and Storage Unit. This combination will support large-scale investigation of structural and fuel cladding material compatibility issues with heavy-metal coolants, oxygen chemistry control, and thermal hydraulic physics properties. Its ability to reconfigure flow conditions and piping configurations to more accurately approximate prototypical reactor designs will provide a key resource for Lead Fast Reactor research and development. The other principal elements of the Lead-Bismuth Eutectic Test Facility (in addition to the Pool Unit and Storage Unit) are the Bench Scale Unit and Supporting Systems, principal of which are the O2 Sensor/Calibration System, Feed System, Transfer System, Off- Gas System, Purge and Evacuation System, Oxygen Sensor and Control System, Data Acquisition and Control System, and the Safety Systems. Parallel and/or independent corrosion studies and convective heat transfer experiments for cylindrical and annular geometries will support investigation of heat transfer phenomena into the secondary side. In addition, molten metal pumping concepts and power requirements will be measured for future design use
New Horned Dinosaurs from Utah Provide Evidence for Intracontinental Dinosaur Endemism
Background:\ud
During much of the Late Cretaceous, a shallow, epeiric sea divided North America into eastern and western landmasses. The western landmass, known as Laramidia, although diminutive in size, witnessed a major evolutionary radiation of dinosaurs. Other than hadrosaurs (duck-billed dinosaurs), the most common dinosaurs were ceratopsids (large-bodied horned dinosaurs), currently known only from Laramidia and Asia. Remarkably, previous studies have postulated the occurrence of latitudinally arrayed dinosaur “provinces,” or “biomes,” on Laramidia. Yet this hypothesis has been challenged on multiple fronts and has remained poorly tested.\ud
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Methodology/Principal Findings:\ud
Here we describe two new, co-occurring ceratopsids from the Upper Cretaceous Kaiparowits Formation of Utah that provide the strongest support to date for the dinosaur provincialism hypothesis. Both pertain to the clade of ceratopsids known as Chasmosaurinae, dramatically increasing representation of this group from the southern portion of the Western Interior Basin of North America. Utahceratops gettyi gen. et sp. nov.—characterized by short, rounded, laterally projecting supraorbital horncores and an elongate frill with a deep median embayment—is recovered as the sister taxon to Pentaceratops sternbergii from the late Campanian of New Mexico. Kosmoceratops richardsoni gen. et sp. nov.—characterized by elongate, laterally projecting supraorbital horncores and a short, broad frill adorned with ten well developed hooks—has the most ornate skull of any known dinosaur and is closely allied to Chasmosaurus irvinensis from the late Campanian of Alberta.\ud
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Conclusions/Significance:\ud
Considered in unison, the phylogenetic, stratigraphic, and biogeographic evidence documents distinct, co-occurring chasmosaurine taxa north and south on the diminutive landmass of Laramidia. The famous Triceratops and all other, more nested chasmosaurines are postulated as descendants of forms previously restricted to the southern portion of Laramidia. Results further suggest the presence of latitudinally arrayed evolutionary centers of endemism within chasmosaurine ceratopsids during the late Campanian, the first documented occurrence of intracontinental endemism within dinosaurs
Physiological Correlates of Volunteering
We review research on physiological correlates of volunteering, a neglected but promising research field. Some of these correlates seem to be causal factors influencing volunteering. Volunteers tend to have better physical health, both self-reported and expert-assessed, better mental health, and perform better on cognitive tasks. Research thus far has rarely examined neurological, neurochemical, hormonal, and genetic correlates of volunteering to any significant extent, especially controlling for other factors as potential confounds. Evolutionary theory and behavioral genetic research suggest the importance of such physiological factors in humans. Basically, many aspects of social relationships and social activities have effects on health (e.g., Newman and Roberts 2013; Uchino 2004), as the widely used biopsychosocial (BPS) model suggests (Institute of Medicine 2001). Studies of formal volunteering (FV), charitable giving, and altruistic behavior suggest that physiological characteristics are related to volunteering, including specific genes (such as oxytocin receptor [OXTR] genes, Arginine vasopressin receptor [AVPR] genes, dopamine D4 receptor [DRD4] genes, and 5-HTTLPR). We recommend that future research on physiological factors be extended to non-Western populations, focusing specifically on volunteering, and differentiating between different forms and types of volunteering and civic participation
Layer Formation on Metal Surfaces in Lead-Bismuth At High Temperatures in Presence of Zirconium
If the operating temperature lead-bismuth cooled fission reactor could be extended to 800 °C, they could produce hydrogen directly from water. A key issue for the deployment of this technology at these temperatures is the corrosion of the fuel cladding and structural materials by the lead-bismuth. Corrosion studies of several metals were performed to correlate the interaction layer formation rate as a function of time, temperature, and alloy compositions. The interaction layer is defined as the narrow band between the alloy substrate and the solidified lead-bismuth eutectic on the surface. Coupons of HT-9, 410, 316L, and F22 were tested at 550 and 650 °C for 1000 h inside a zirconium corrosion cell. The oxygen potential ranged from approximately 10−22 to 10−19 Pa. Analyses were performed on the coupons to determine the depth of the interaction layer and the composition, at each time step (100, 300, and 1000 h). The thickness of the interaction layer on F22 at 550 °C was 25.3 μm, the highest of all the alloys tested, whereas at 650 °C, the layer thickness was only 5.6 μm, the lowest of all the alloys tested. The growth of the interaction layer on F22 at 650 °C was suppressed, owing to the presence of Zr (at 1500 wppm) in the LBE. In the case of 316L, the interaction layers of 4.9 and 10.6 μm were formed at 550 and 650 °C, respectively
Preliminary FRAPCON-3Th Steady-State Fuel Analysis of ThO₂ and UO₂ Fuel Mixtures
Recent investigations into the performance and economics of mixed thoria-urania (ThO2/UO2) fuel cycles in light water reactors indicate that there may be advantages to using these fuels at high burnups. The Idaho National Engineering and Environmental Laboratory (INEEL) modified FRAPCON-3, a U.S. Nuclear Regulatory Commission-sponsored software package developed by Pacific Northwest National Laboratory for use on mixed thoria-urania fuels. The modifications constituted the first stage of fuel performance evaluations supported by the Nuclear Energy Research Initiative (NERI) project titled Advanced Proliferation Resistant, Lower Cost, Uranium-Thorium Dioxide Fuels for Light Water Reactors. The goal of this NERI project is to develop mixed ThO2/UO2 fuels that can be operated to a relatively high burnup level in current and future commercial power reactors. This paper describes in detail the INEEL\u27s modifications to the FRAPCON-3 thermal conductivity subroutine FTHCON and the techniques used to validate the modifications. The paper presents the general fuel design criteria used to model mixed thoria-urania fuel and a steady-state analysis of a mock thoria-urania fuel using the FRAPCON-3Th code. The paper also presents the data analyses for the mock thoria-urania fuel and offers suggestions for future upgrades and improvements to the code
Preservation of aqueous outflow facility after second-generation FIV vector-mediated expression of marker genes in anterior segments of human eyes. Invest Ophthalmol Vis Sci.
PURPOSE. Feline immunodeficiency virus (FIV)-based lentiviral vectors produce effective genetic modification of the trabecular meshwork (TM) of human eyes in organ-perfusion culture, resulting in high-level expression of a -galactosidase marker gene (lacZ) without loss of TM cellularity or architecture. However, effects on aqueous outflow physiology have not been determined, and the ability to monitor FIV vector transgene expression in living TM in situ has not been established. In the current study, transgene expression and outflow facility were evaluated in perfused human anterior segments after FIV vector transduction of lacZ or of a marker gene that can be monitored noninvasively, enhanced green fluorescent protein (eGFP). METHODS. Second-generation FIV vectors were made with a protocol for scaled-up production that requires 10 times less input DNA and allows simplified concentration. One vector encodes -galactosidase (vector CT26), and the other (bicistronic) encodes eGFP and neomycin phosphotransferase (vector GiNWF). Three pairs of eyes were injected with 1 ϫ 10 8 transducing units (TU) of CT26 in the right eye and with a control (mock lacZ) vector in the left eye. Three others were injected with 1 ϫ 10 8 TU GiNWF in the right eye only, with the left eye serving as an uninjected control. Intraocular pressure was recorded and transduction efficiency was determined. RESULTS. The modified protocol produced high-titer FIV vectors, and coordinate expression of marker genes was observed with the bicistronic vector. In human eyes, the eGFP and lacZ vectors transduced 79% Ϯ 15% and 82% Ϯ 4% of TM cells, respectively, without cell loss compared with control eyes. Transduction and marker gene expression caused a transient decrease of outflow facility (30% Ϯ 22%, P ϭ 0.02), which resolved after 48 to 72 hours. CONCLUSIONS. FIV vectors produce high-level expression of eGFP in the TM of the cultured human eye, with transduction efficiency similar to that obtained with -galactosidase vectors. Transduction and expression of these marker genes results in small and transient changes in outflow facility, suggesting suitability of this class of vectors for glaucoma gene therapy. (Invest Ophthalmol Vis Sci. 2002;43:3686 -3690) H igh intraocular pressure is the most common causal risk factor for glaucoma and is the key variable for clinical management. Intraocular pressure is primarily determined by aqueous humor production and outflow. The trabecular meshwork (TM) generates most of the resistance to outflow, which normally maintains intraocular pressure within the narrow range (10 -21 mm Hg) that is essential for viability of the neuroretina. Impairment of TM-regulated outflow is believed to be the primary physiological derangement in the majority of primary open-angle glaucoma patients