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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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At least 451 records · Page 25
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Evaluation of high performance large grain medium purity SRF cavity from KEK

We presented the RF measurement on a 1.3 GHz single cell cavity fabricated at KEK using large grain ingot niobium with RRR=107. The cavity reached to 35 MV/m with Q 0 = 2.0×10zEhNZeHn at 2.0 K, record performance on the cavity made from medium purity ingot niobium. The cavity was cool down with different temperature gradient along the cavity axis in order to understand the flux expulsion mechanism when the cavity does through the superconducting transition and effect of trap residual magnetic field on the residual resistance. The measurement showed the excellent flux expulsion with the flux trapping sensitivity of 0.29 nΩ/mG for electro polished surface and 0.44 nΩ/mG for cavity followed by low temperature baking at 120°C for 12 hours.

Dhakal, P.↗
DOE OSTI2022

Cyber Resilient Design and Controls for Energy Systems

As the grid of today is evolving into a highly distributed and autonomous cyber-physical system with higher penetration of Distributed Energy Resources (DERs) and autonomous controls that are dependent on the cyber infrastructure, there are novel and increasing challenges to cyber-resilient operation of the grid. While the traditional mechanisms take a "bolt on" approach to cybersecurity and resiliency, this talk presents two novel technologies developed at NREL that "bake in" security and resilience into the design and control of the grid. An Adaptive Resilience Metrics framework is a novel mechanism for system owners and operators to understand the impact of cyber and physical system design and topology on the resilient operation, while also helping determine optimal policies in response to adverse cyber events. Along with that a zero-knowledge proof-based technique helps incorporate security into the controls layer by focusing on computational integrity rather than data integrity. By leveraging design and control properties unique to Operational Technology systems these technologies will not only help enhance cyber-resilience for the grid of today, but a highly distributed and autonomous grid of tomorrow.

cyber resilience↗
DOE OSTI2023

The Collaborative Effects of Intrinsic and Extrinsic Impurities in Low RRR SRF Cavities

The superconducting radio-frequency (SRF) community has shown that introducing certain impurities into high-purity niobium can improve quality factors and accelerating gradients. We question why some impurities improve RF performance while others hinder it. The purpose of this study is to characterize the impurity profile of niobium with a low residual resistance ratio (RRR) and correlate these impurities with the RF performance of low RRR cavities so that the mechanism of impurity-based improvements can be better understood and improved upon. The combination of RF testing and material analysis reveals a microscopic picture of why low RRR cavities experience low temperature-dependent BCS resistance behavior more prominently than their high RRR counterparts. We performed surface treatments, low temperature baking and nitrogen-doping, on low RRR cavities to evaluate how the intentional addition of oxygen and nitrogen to the RF layer further improves performance through changes in the mean free path and impurity profile. The results of this study have the potential to unlock a new understanding on SRF materials and enable the next generation of SRF surface treatments.

43 PARTICLE ACCELERATORS↗
DOE OSTI2023

The Collaborative Effects of Intrinsic and Extrinsic Impurities in Low RRR SRF Cavities

The SRF community has shown that introducing certain impurities into high-purity niobium can improve quality factors and accelerating gradients. We question why some impurities improve RF performance while others hinder it. The purpose of this study is to characterize the impurity profile of niobium coupons with a low residual resistance ratio (RRR) and correlate these impurities with the RF performance of low RRR cavities so that the mechanism of impurity-based improvements can be better understood and improved upon. The combination of RF testing and material analysis reveals a microscopic picture of why low RRR cavities experience low BCS resistance behavior more prominently than their high RRR counterparts. We performed surface treatments, low temperature baking and nitrogen-doping, on low RRR cavities to evaluate how the intentional addition of oxygen and nitrogen to the RF layer further improves performance through changes in the mean free path and impurity profile. Th e results of this study have the potential to unlock a new understanding on SRF materials and enable the next generation of high Q/high gradient surface treatments.

Howard, K.↗
DOE OSTI2023

The Collaborative Effects of Intrinsic and Extrinsic Impurities in Low RRR SRF Cavities

The SRF community has shown that introducing certain impurities into high-purity niobium can improve quality factors and accelerating gradients. We question why some impurities improve RF performance while others hinder it. The purpose of this study is to characterize the impurity profile of niobium coupons with a low residual resistance ratio (RRR) and correlate these impurities with the RF performance of low RRR cavities so that the mechanism of impurity-based improvements can be better understood and improved upon. The combination of RF testing and material analysis reveals a microscopic picture of why low RRR cavities experience low BCS resistance behavior more prominently than their high RRR counterparts. We performed surface treatments, low temperature baking and nitrogen-doping, on low RRR cavities to evaluate how the intentional addition of oxygen and nitrogen to the RF layer further improves performance through changes in the mean free path and impurity profile. The results of this study have the potential to unlock a new understanding on SRF materials and enable the next generation of high Q/high gradient surface treatments.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2023

Exploration of Parameters That Affect High Field Q-Slope

The onset of high field Q-slope (HFQS) around 25 MV/m prevents cavities in electropolished (EP) condition from reaching high quality factors at high gradients due to the precipitation of niobium hydrides during cooldown. These hydrides are non-superconducting at 2 K, and contribute to losses such as Q disease and HFQS. We are interested in exploring the parameters that affect the behavior of HFQS. We study a high RRR cavity that received an 800 C by 3 hour bake and EP treatment to observe HFQS. First, we explore the effect of trapped magnetic flux. The cavity is tested after cooling slowly through Tc while applying various levels of ambient field. We observe the onset of the HFQS and correlate this behavior with the amount of trapped flux. Next, we investigate the effect of the size/concentration of hydrides. The cavity is tested after holding the temperature at 100 K for 12 hours during the cooldown to promote the growth of hydrides. We can correlate the behavior of the HF QS with the increased hydride concentration. Our results will help further the understanding of the mechanism of HFQS.

43 PARTICLE ACCELERATORS↗
DOE OSTI2013

Model nitride irradiated nuclear fuel: production, reaction with water and dilution in nitric acid

Samples of the model nuclear fuel (MNF) were made from separately synthesized nitride powders uranium-plutonium, zirconium, lanthanum and metal additives of simulators (Mo, Pd, Rh, Ag) fission products. Synthesis of initial nitride components was carried out from individual oxides, using a carbo-thermal restoration method. From MNF samples baked at a temperature of 1750 C. degrees, were made ceramographic specimens which were investigated by a scanning electron microscope. The analysis showed that distribution of the MNF components and structure of the samples corresponds to distribution of these components in the irradiated nitride fuel. The samples of MNF of nitride fuel were used for carrying out researches on dissolution in water and nitric acid. Experiments on studying the interaction of MNF with water have been made at 20, 50 and 80 C. degrees. The speed of leaching has been determined by a way of measuring the activity of water (Bq/l) in time. It is shown that an increase of temperature leads to an increase of the speed of leaching of plutonium. The formation of a precipitation, allegedly polymeric forms of plutonium, has been observed. The estimated speed of leaching of plutonium from MNF in water at 80 C. degrees is -0,0064 μgPu/(mm{sup 2}*h). From elements of FP simulators, molybdenum appears to be the most significantly leached. The dissolution of MNF in nitric acid (7,8 and 9,4 mol/l) has been carried out at boiling temperature (106-109 C. degrees). During the process of dissolution, gases were emitted. The assessment of composition of the emitted gases has been carried out. During the filtering of the solutions a precipitate whose weight makes about 2% from the weight of initial fuel has been found. Precipitate represents small powder of metal with gray color. Precipitate was investigated by a scanning electron microscope. The analysis of ranges of absorption of solution showed that the Pu(VI) share to the general content of plutonium in solution can reach 40%. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2012

Consolidation and Centralization of Waste Operations Business Systems - 12319

This abstract provides a comprehensive plan supporting the continued development and integration of all waste operations and waste management business systems. These include existing systems such as ATMS (Automated Transportation Management System), RadCalc, RFITS (Radio Frequency Identification Transportation System) Programs as well as incorporating key components of existing government developed waste management systems and COTS (Computer Off The Shelf) applications in order to deliver a truly integrated waste tracking and management business system. Some of these existing systems to be integrated include IWTS at Idaho National Lab, WIMS at Sandia National Lab and others. The aggregation of data and consolidation into a single comprehensive business system delivers best practices in lifecycle waste management processes to be delivered across the Department of Energy facilities. This concept exists to reduce operational costs to the federal government by combining key business systems into a centralized enterprise application following the methodology that as contractors change, the tools they use to manage DOE's assets do not. IWITS is one efficient representation of a sound architecture currently supporting multiple DOE sites from a waste management solution. The integration of ATMS, RadCalc and RFITS and the concept like IWITS into a single solution for DOE contractors will result in significant savings and increased efficiencies for DOE. Building continuity and solving collective problems can only be achieved through mass collaboration, resulting in an online community that DOE contractors and subcontractors access common applications, allowing for the collection of business intelligence at an unprecedented level. This is a fundamental shift from a solely 'for profit' business model to a 'for purpose' business model. To the conventional-minded, putting values before profit is an unfamiliar and unnatural way for a contractor to operate - unless however; your objective is to build a strong, strategic alliance across the enterprise in order to execute an unprecedented change in waste management, transportation and logistical operations. The success of such an initiative can be achieved by creating a responsible framework by enabling key individuals to 'own' the sustainability of the program. This includes the strategic collaboration of responsible revolutionaries covering application developers, information owners and federal stakeholders to ensure compliance, security and risk management are 'baked' into the process and sustainability is fostered through continued innovation by both technology and application functionality. This ensures that working software can adapt to changing circumstances and is the principle measure of the success of the program. The consolidation of waste management business systems must be achieved in order to realize efficiencies in information technology portfolio management, data integrity, business intelligence and the lifecycle management of hazardous materials within the DOE enterprise architecture. By identifying best practices across the enterprise and aggregating computational and application development resources, you can provide a unified, holistic solution serviceable from a single location while being accessed from anywhere. The business impact of integrating and delivering a unified solution would reduce costs to the Department of Energy within the first year of deployment with increased savings annually. (author)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Ensuring NQA-1 Compliance with Nuclear Next Gen Technologies Performing a Safety Function Associated with Autonomy or Remote Systems - 17549a

First-of-a-kind and cutting edge Next Gen technologies deployed in a nuclear environment may initially appear to fall outside the ability to be qualified in accordance with ASME NQA-1 for a nuclear safety function. However, NQA-1 compliance is possible especially if baked into the early stages of the technology development process. This is particularly applicable as part of the increasingly prevalent application of autonomous processes, advanced manipulation, man-machine interfaces, exoskeletons and other advanced and unique ability options. (authors)

42 ENGINEERING↗
DOE OSTI2016

ITER Port Interspace Pressure Calculations

The ITER ('the way' in Latin) project in Cadarache, France, will operate the largest tokamak ever built to demonstrate the physical and technical feasibility of nuclear fusion as an energy source. The ITER vacuum vessel is equipped with 50 access ports. Each port has an opening in the bio-shield that communicates with a dedicated port cell. During tokamak operation, the bio-shield opening must be closed with a concrete plug to shield the radiation coming from the plasma. This port plug separates the port cell into a port interspace (between vacuum vessel closure lid and port plug) on the inner side and a port cell on the outer side. This paper presents calculations of pressures and temperatures in the ITER port interspace after a double-ended guillotine break (DEGB) of a pipe in the tokamak cooling water system (TCWS). It is assumed that the DEGB occurs during the worst possible conditions-during water baking operation, with water at 523 K (250 deg. C) and 4.4 MPa. These conditions are more severe than during normal tokamak operation with the water at 398 K (125 deg. C) and 2 MPa. Two computer codes are employed in these calculations: RELAP5-3D Version 4.2.1 to calculate blowdown releases from the pipe break, and MELCOR, Version 1.8.6 to calculate pressures and temperatures in the port interspace. A sensitivity study has been performed to optimize the maximum peak pressure in the port interspace volume of ITER. The optimum case was for a labyrinth area (FL131) of 0.5 m{sup 2} and a relief panel (FL135) kept open after the first cycle. This case keeps the pressure in the port interspace under 150 kPa and the temperatures under 385 K. (authors)

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

Adhesion Capabilities of Permanent Foaming Fixatives

DOE-EM have identified an operational requirement for a fixative that can immobilize and/or encapsulate residual contamination in 3D void volumes (pipes, gloveboxes, waste containers, etc.) during D and D activities. Failure to safely and effectively immobilize residual contamination can: Put workers at risk; Contaminate the public and environment; Drive up costs. Commercial-off-the-shelf (COTS) polyurethane (PU) foams is one possible solution and is currently being investigated by Savannah River National Lab (SRNL). Adhesion testing will dictate how well PU foams will adhere and immobilize residual contamination onto a substrate. Results can provide a performance criteria for Section 5 of ASTM E3191: Standard Specification for Permanent Foaming Fixatives Used to Mitigate Spread of Radioactive Contamination. Initial mechanical testing showed intumescent rigid PU foams were best in class (tensile, compression, TGA/DSC) Application of intumescent rigid PU foam in pipe scenario with 'contamination' showed excellent adhesion capabilities as long as foam had contact with pipe. The foam, however, was not able to penetrate 'contamination' but created pockets where the contamination interacted with the substrate. Pretreatment options of pipe were considered to produce better immobilization capabilities. Pretreatment options included COTS products like baking spray, rubber cement, and soap. Foam was still able to immobilize on a global sense, but not a local sense. Essentially acted as a mechanical plug. A tensile tester (MTS Criterion Series 43) was utilized to evaluate the tensile adhesion strength of 6 COTS PU foams. ASTM D1623: Tensile and Tensile Adhesion Properties of Rigid Cellular Plastics. Procedures: PU foams were cured between two smooth 2'' x 2'' 304 stainless steel coupons with hinges glued on plates for gripping support. Parameters Used: Pull rate of 0.1 in/min. Calculations: Tensile adhesion strength, elongation, and ImageJ analysis of how PU foam is left on substrate. Outcome: The PU foam with the best adhesion capabilities would be downselected for further evaluation to be used as a permanent foaming fixative. The rigid PU foams had the best adhesion capabilities with the R1 foam having a max load of 236 N. One of the I-R2 samples reached almost 450 N and another sample reached 2500 N before slipping. The other intumescent foam, I-F4, had the most coverage on the stainless steel coupon's surface from the ImageJ results (61.43% surface coverage). The intumescent foam, I-R2, will be the foam of choice for future testing due its fire retardant and adhesion capabilities. Future directions: Conduct the following experiment in a pipe scenario with the down-selected PU foam. Procedures: PU foam will be cured between in a 304 stainless steel pipe (ID: 4'', OD: 4.5'', Height: 4''). Parameters Used: Compression testing results will be referenced to determine if foam's adhesion strength would be greater its compression strength as its being compressed. Calculations: Compression strength, shear stress, total time elapsed. Conduct further adhesion testing with the down-selected PU foam (I-R2) to be treated as a permanent foaming fixative (PFF). Determine the minimum contact the PFF should have with the substrate for adequate results. Evaluate if PFF's adhesion capabilities is time dependent (3.1.5 of ASTM E3911). Subject PFF to seismic stressors addressed in Safety Basis of Interim Operation documents (SBIO) to further evaluate adhesion capabilities.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2025

Simulating Alpha Particles Incident on MKID Chips for Quantum Sensitivity Analysis

• Background noise from ionizing decay poses challenges for MKIDs due to their sensitivity to small energy depositions. • Our group bakes the MKID housing lid in radon to study effects of alphas from daughter isotopes in the decay chain. • The impact of alpha particles on the chip depends on their energy, making their distribution key to characterizing and reducing noise in superconducting quantum devices.

Hall, Matthew [Southern California U.]↗
DOE OSTI2023

An alternative viewpoint on the nuclear structure towards 100 Sn: Lifetime measurements in 105 Sn

This work aims at presenting an alternative approach to the long standing problem of the B(E2) values in Sn isotopes in the vicinity of the N=Z double-magic nucleus 100 Sn, until now predominantly measured with relativistic and intermediate-energy Coulomb excitation reactions. The direct measurement of the lifetime of low-lying excited states in odd-even Sn isotopes provides a new and precise guidance for the theoretical description of the nuclear structure in this region. Lifetime measurements have been performed in 105 Sn for the first time with the coincidence Recoil Distance Doppler Shift technique. The lifetime results for the $7/2^+_1$ first excited state and the $11/2^+_1$ state, $2^+ (^{104}$Sn) Ⓧ $v1g_{7/2}$ multiplet member, are discussed in comparison with state-of-the-art shell model and mean field calculations, highlighting the crucial contribution of proton excitation across the core of 100 Sn. The reduced transition probability B(E2) of the $11/2^+_1$ core-coupled state points out an enhanced staggering with respect to the B(E2; $2^+_1$ → $0^+_1$) in the even-mass 104 Sn and 106 Sn isotopes.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2018

Chemical, Molecular, and Microstructural Evolution of Kerogen during Thermal Maturation: Case Study from the Woodford Shale of Oklahoma

Integrated elemental, spectroscopic (infrared spectroscopy and X-ray absorption near-edge structure), and gas intrusion (helium pycnometry and nitrogen adsorption) analyses are used to characterize the bulk chemical, molecular, and physical microstructures of kerogen spanning a thermal maturity transect (vitrinite reflectance, Ro, from 0.5% to 2.6%) across the Woodford Shale of the Anadarko Basin, Oklahoma. The integration takes advantage of novel procedures to prepare kerogen isolates that preserve both the chemical and physical properties of the organic matter in the bulk shale. The Woodford kerogens follow the expected trends in H/C and O/C coordinates during thermal maturation for type II kerogen. Infrared spectra show that loss of hydrogen from kerogen is related to cracking of hydrogen-rich aliphatic (alkyl) carbon structures from aromatic carbons. Within the range of Ro values < 1.5%, peripheral aromatic carbons remain highly substituted with alkyl (methyl and methylene) and probably heteroatom functional groups. At Ro values > 1.5%, these substitutions are substantially removed and replaced by hydrogen. The evolution of carbon structures inferred from the IR spectra is supported by known carbon bond dissociation energies for carbonaceous materials. Total organic sulfur and sulfur-XANES data show that sulfur in Woodford kerogens is dominated by aromatic sulfur (thiophene) and that reactive, aliphatic sulfur (sulfide) is eliminated at low degrees of thermal stress (Ro ≤ 0.9%). At higher thermal stress, sulfur speciation is stable and dominated by thermally stable thiophene. The physical properties of Woodford kerogens evolve during thermal maturation in a manner consistent with their molecular characteristics. Skeletal density of kerogen increases during maturation in a manner that is linearly correlated to its atomic H/C ratio and inferred aromatic carbon content. The specific surface area of kerogen also increases during maturation, reflecting the development of internal pores within the kerogen skeletal framework as aliphatic carbon structures are preferentially cracked and expelled from solid kerogen. The quantitative chemical and structural changes expressed by the Woodford kerogens during thermal maturation, including their hydrogen and carbon content, carbon speciation, and skeletal density, are shown by comparison to not be measurably different for other type II kerogens from numerous oil- and gas-producing shale plays, indicating that thermal stress acts to drive maturation of type II kerogen in a similar way globally.

58 GEOSCIENCES↗