Intelligent Long Endurance Observing System (ILEOS)
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high altitude long endurance↗
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Results for “endurance”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Development of Radiation Endurance Ultrasonic Transducer for Nuclear Reactors
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46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
CeO 2 Doping of Hf 0.5 Zr 0.5 O 2 Thin Films for High Endurance Ferroelectric Memories
Ferroelectric switching is demonstrated in CeO 2 -doped Hf 0.5 Zr 0.5 O 2 (HZCO) thin films with application in back-end-of-line compatible embedded memories. At low cerium oxide doping concentrations (2.0–5.6 mol%), the ferroelectric orthorhombic phase is stabilized after annealing at temperatures below 400 °C. HZCO ferroelectrics show reliable switching characteristics beyond 10 11 cycles in TiN/HZCO/TiN capacitors, several orders of magnitude greater than identically processed Hf 0.5 Zr 0.5 O 2 (HZO) capacitors, without sacrificing polarization and retention. Internal photoemission and photoconductivity experiments show that CeO 2 -doping introduces in-gap states in HZCO that are nearly aligned with TiN Fermi level, facilitating electron injection through these states. Furthermore, the enhanced average bulk conduction, which may lead to more uniform thermal dissipation in the HZCO films, delays irreversible degradation via breakdown that leads to device failure after repeated programming cycles.
36 MATERIALS SCIENCE↗
Endurance exercise elicits temporal and sexual dimorphic multi-omics remodeling of liver metabolism revealed by MoTrPAC
The mechanisms by which exercise modulate liver metabolism, a central regulator of systemic metabolism, are poorly understood. Leveraging data from MoTrPAC, we analyzed liver adaptations across 1, 2, 4, and 8 weeks of exercise in male and female rats using multi-omic approaches. Female livers displayed a progressive increase in oxidative phosphorylation (OXPHOS) complexes (at the protein level), while male livers showed an increase in acetylation of OXPHOS, TCA cycle, and fatty acid oxidation enzymes. Exercise also enhanced liver cholesterol and bile acid synthesis, reducing liver lipid metabolites in males after 8 weeks of exercise. Male rats had higher fecal cholesterol and cholic acid levels, indicating a sex-specific mechanism of lipid excretion with exercise. Moreover, 8 weeks of training reduced markers related to hepatic stellate cell activation and fibrosis in both sexes. This study highlights the sexual dimorphic and temporal molecular signatures by which exercise modulates liver metabolism to provide hepatoprotective effects.
Kelty, Taylor↗
High-Endurance Magneto-Electronic Switchable Molecular Electronic Crystal
Electrically switchable magnetic and electronic properties are promising for quantum sensing and information technology. Here, we report an electrically driven magnetic and electronic phase transition in molecular electronic crystal, potassium-7,7,8,8-tetracyanoquinodimethan, with the magneto-electric switching over 105 cycles at room temperature. Electron spin resonance study reveals the cooperative transition between spin and charge degrees of freedom. In addition, the mechanistic spectroscopy studies suggest the charges in an inhomogeneous conductor–insulator mixed state. Furthermore, the findings shown here suggest electrically controlled ordering in strongly correlated molecular crystal leads to dynamic magneto-electric switching, paving the way for developing molecular-based memory and switching devices.
77 NANOSCIENCE AND NANOTECHNOLOGY↗
Fe 2 P-decorated N,P Codoped Carbon Synthesized via Direct Biological Recycling for Endurable Sulfur Encapsulation
Not Available
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
The enduring role of contracts for difference in risk management and market creation for renewables
Governments procure renewables through a variety of mechanisms. Contracts for difference (CfDs) have been used for more than 50% of the global offshore wind supply. The payments awarded through CfDs are sometimes labelled subsidies, suggesting that they support uneconomic activity. Here, in this study, we argue that the primary role of CfDs is rather risk management by creating a market for electricity supply at stable long-term prices. Similar to its use in other sectors of the economy, this contract type transforms a variable to a fixed price to reallocate volatility risks. Such long-term contracts are often necessary for renewables financing due to limited hedging options in existing markets. Our perspective could imply a shift in perception towards CfDs as a fundamental and lasting market feature. We hope to stimulate a timely discussion about the impact of greater CfD diffusion on electricity market mechanisms, risk allocation and the potential for combining fragmented streams of energy finance, market and policy research.
29 ENERGY PLANNING, POLICY, AND ECONOMY↗
The enduring legacy of Marie Curie: impacts of radium in 21st century radiological and medical sciences
Not Available
62 RADIOLOGY AND NUCLEAR MEDICINE↗
Granal thylakoid structure and function: explaining an enduring mystery of higher plants
Summary In higher plants, photosystems II and I are found in grana stacks and unstacked stroma lamellae, respectively. To connect them, electron carriers negotiate tortuous multi‐media paths and are subject to macromolecular blocking. Why does evolution select an apparently unnecessary, inefficient bipartition? Here we systematically explain this perplexing phenomenon. We propose that grana stacks, acting like bellows in accordions, increase the degree of ultrastructural control on photosynthesis through thylakoid swelling/shrinking induced by osmotic water fluxes. This control coordinates with variations in stomatal conductance and the turgor of guard cells, which act like an accordion's air button. Thylakoid ultrastructural dynamics regulate macromolecular blocking/collision probability, direct diffusional pathlengths, division of function of Cytochrome b 6 f complex between linear and cyclic electron transport, luminal pH via osmotic water fluxes, and the separation of pH dynamics between granal and lamellar lumens in response to environmental variations. With the two functionally asymmetrical photosystems located distantly from each other, the ultrastructural control, nonphotochemical quenching, and carbon‐reaction feedbacks maximally cooperate to balance electron transport with gas exchange, provide homeostasis in fluctuating light environments, and protect photosystems in drought. Grana stacks represent a dry/high irradiance adaptation of photosynthetic machinery to improve fitness in challenging land environments. Our theory unifies many well‐known but seemingly unconnected phenomena of thylakoid structure and function in higher plants.
59 BASIC BIOLOGICAL SCIENCES↗
Enduring Transuranic Liquid Waste Volume Forecast and Constituent Evaluation (FY20)
The “FY11 Radioactive Liquid Waste (RLW) Influent Boundary Condition Assessment and Forecast” report provided influent volume forecasts that were critical in establishing the design capacity for the new Radioactive Liquid Waste Transuranic (RLW-TRU) capability. The design for the new RLW-TRU capability was paused as the final design was being completed and prior to the transition of the new management and operations contract for Los Alamos National Laboratory (LANL). Recently, NNSA has directed the project to restart and complete the design effort. As part of the restart process, LANL was asked to validate or document any material changes in the influent volumes or constituents that formed the design basis for the new capability. This analysis updates the transuranic liquid waste influents volumes, incorporating the changes in the LANL program of record since the FY11 assessment, and includes a cursory validation of influent constituents. The results of the FY19 update to influent volume forecasts shows: 1) the influent volume of 29,000 L should continue to be used as the project design-basis; 2) There have been no material changes in the operational processes that would change the constituents of concern from either a treatment or material compatibility perspective.
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Developing Accelerated Test Protocols and Tuning Microstructures of the Common Materials to Improve Robustness, Reliability, and Endurance of SOFC Cells
This work is built on our prior work where we found that phase transformation in praseodymium nickelates, e.g. Pr 2 NiO 4 (PNO) and (Pr 1-x Nd x ) 2 NiO 4 (PNNO), can be electrochemically driven, and is substantially faster when compared to thermal annealing studies. The first task aims at an attempt to further accelerate the phase transformation in the oxygen electrode by alternating the current input in the cells, which lead to the development of accelerated test protocols (ATPs). ATPs showed up to 60x faster phase transformation and up to 10x faster performance degradation in (Pr 0.50 Nd 0.50 ) 2 NiO 4 electrodes, when compared to long-term operation under constant current density. Furthermore, the phase stable Nd 2 NiO 4 and (La 0.6 Sr 0.4 )(Co 0.8 Fe 0.2 )O 3 (LSCF6482) electrodes were tested in full cells under ATPs, and showed up to 10x faster performance degradation within 1,100 hours in a comparison with long-term thermal annealing studies and electrochemical operation under constant current density. The second task aims at the quantification of the contributions of cell components to the total impedance of a solid oxide fuel cell (SOFC) using electrochemical impedance spectroscopy (EIS) and distribution of relaxation times (DRT). Specifically, the role of gas composition at both anode and cathode was systematically studied, aiming at deconvoluting, identifying and quantifying the contributions of different electrode processes. This was achieved by first tuning the partial pressure of H 2 at the anode and subsequently varying the partial pressure of O 2 at the cathode. The results suggest that, while DRT offers a viable way of deconvoluting different times distributions, additional attention is needed before assigning a peak to a specific electrode process due to the significant overlap of the contributions from the cathode and the anode. Density function theory studies show that both Pr-vacancies and O-defects play a key role on the activity and stability for nickelates towards oxygen reduction reaction. The resident O-interstitials and oxygen ions in the PrO layer form peroxide (O 2 2- ) nearby Pr vacancies. The O 2 2- limits oxygen-ion transport due to the required additional energy to break its O-O bond. We further calculated the formation and segregation energies for different Ln ions (La, Pr, Nd, Pm, Sm, Gd, Tb, Dy, and Ho) in PNO and CeO 2 (111) surfaces. In addition to Nd, Pm and La are suggested as potential dopants in PNO to enhance it stability without decomposition due to their more negative formation energies, lower diffusion energies, and positive separation energies.
01 COAL, LIGNITE, AND PEAT↗
Self-Cleaning Cathodes for Endurance to Chromium Poisoning
Chromium (Cr) poisoning remains a significant issue in long-term solid oxide fuel cell (SOFC) operation. While the addition of Cr in the interconnect and balance-of-plant (BOP) materials is effective in improving their resistance to oxidation, it also causes the deposition of resistive phases in the air electrode and thus cell performance loss. Previous work has investigated the mitigation of chromium deposition using getters, Cr diffusion resistant coatings, and more chromium-tolerant air electrode materials. However, these mitigation strategies merely postpone the degradation of performance due to Cr poisoning. Additionally, some strategies require the replacement of components, e.g., use of getters. Here we investigated a new, in-situ Cr poisoning mitigation strategy.
30 DIRECT ENERGY CONVERSION↗
DARHT : Enduring Lessons from a Technical Project in a National Laboratory Context [Slides]
The Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory (LANL) is the world’s first flash x-ray facility able to take multiple high-resolution radiographs of the interior features of fast-moving dense objects during a single experiment. DARHT’s radiography and complimentary diagnostics makes it an important diagnostic tool in support of the US Department of Energy’s (DOE)/National Nuclear Security Administration (NNSA)’s stewardship of the US nuclear deterrent. The project to construct DARHT ran from 1988 through 2003. Initial Operating Capability along a single axis began in 1999. A technical issue delayed Critical Decision 4 for the full dual-axis capability until 2008. DARHT was characterized by several directed changes resulting from an environmental impact study, changes to the global security context resulting from the end of underground nuclear testing, and rapid evolution of applicable technology. Conventional building and lab-space construction were part of the project, but the project was dominated by Special Facility Equipment that, together with the mission to support the nuclear weapons program, required the project to be completed by national laboratories. Although the project pre-dated implementation of DOE Order 413.3, several important lessons for national laboratory projects remain applicable today and will be discussed here, including projects appropriate for the national laboratory environment, scope stability, risk acceptance and mitigation, communication, and collaboration. Finally, considerations for DOE contractor project managers are offered based upon the DARHT experience.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
CAAS Replacement in Enduring Facilities
CAAS replacement is an essential part to extending facility lifespan
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Economic Long-Duration Electricity Storage by Using Low-Cost Thermal Energy Storage and High-Efficiency Power Cycle (ENDURING)
The project involved considerable industry participation including General Electric (GE, power cycle analysis), Babcock & Wilcox (B&W), Allied Mineral Products (insulation materials), and Worley-Advisian (system integration). They provided insights on their products or services for component and system designs. The project successfully achieved the project goals of demonstrating technology feasibility for long duration energy storage with a technology path towards 5c/kWh levelized cost of storage. The project has generated four patent applications (one awarded patent and three under review), three published journal papers, a draft book chapter, and five manuscripts under preparation, with several conference papers and numerous presentations including invited talks. An intellectual properties (IP) option agreement has been signed with an U.S. manufacturer, with interests from energy developers. Four related projects with $5.5 million DOE funding support more developments for long duration energy storage and broad industry decarbonization.
25 ENERGY STORAGE↗
Small High Endurance Aircraft Technology (sHEAT) - Application of Solid-State Hydrogen Storage to Extend Flight Time of sUAS
Savannah River National Laboratory (SRNL) proposed a study to The Department of Homeland Security (DHS) Science & Technology Directorate (S&T) to investigate the possibility of extending the flight time of small-scale Unmanned Aerial Vehicles (UAVs) using aluminum hydride (AlH 3 or alane) to power a hydrogen fuel cell. Alane is a solid-state hydrogen storage material with greater volumetric energy density than compressed hydrogen and much greater energy density than lithium batteries. UAVs typically use lithium-polymer and lithium-ion batteries for flight, but lithium batteries have not provided a substantial increase in flight time or range since their wide acceptance in the unmanned aircraft market. Several DHS agencies would benefit greatly from extended flight times and ranges for UAS platforms, so experimenting with new types of power sources could provide significant improvement in these important areas of research for DHS S&T.
08 HYDROGEN↗
THIRTY DAY ENDURANCE TEST OF A 30KW ARC JET ENGINE
Details are presented on a 30-day run of a radiation cooled thermal arc jet engine. The engine performed satisfactorily throughout the test period, maintaining a thrust of 250 grams and a propellant specific impulse greater than 1000 seconds a t an input power level of 30 kilowatts. The resulting propulsive efficiency was greater than 40 percent. Visual examination of the arc discharge through a quartz constrictor indicates that there is a smooth, constant diameter, bright core extending from the cathode completely through the constrictor to the cathode. Photographic observations on the arc discharge, using a red filter, indicate that the center of the column is darker than the outside: and this, in turn, suggests that the maximum core temperature is greater than 20,000°K. Calculations on the energy flow rate through a fully developed laminar column, combined with the experimental observation that the longitudinal energy flux gradient along the column is small, suggest that there may be a region of high volumetric energy release in the vicinity of the cathode tip.
Arc jet↗