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DOE OSTI2019

Modelling Environmental Impacts of Cesium-137 Under a Hypothetical Release of Radioactive Waste

Waste tanks at the nuclear facility located at Sellafield, UK, represent a nuclear source which could release radionuclides to the atmosphere. A model chain which combines atmospheric transport, deposition as well as riverine transport to sea has been developed to predict the riverine activity concentrations of {sup 137}Cs. The source term was estimated to be 9 × 10{sup 4} TBq of {sup 137}Cs, or 1% of the assumed total {sup 137}Cs inventory of the HAL (Highly Active Liquid) storage tanks. Air dispersion modelling predicted {sup 137}Cs deposition reaching 127 kBq m{sup −2} at the Vikedal catchment in Western Norway. Thus, the riverine transport model predicted that the activity concentration of {sup 137}Cs in water at the river outlet could reach 9000 Bq m{sup −3} in the aqueous phase and 1000 Bq kg{sup −1} in solid phase at peak level. The lake and river reaches showed different transport patterns due to the buffering effects caused by dilution and slowing down of water velocity.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS1973

The utilization of ERTS-1-generated photographs in the evaluation of the Iranian playas as potential locations for economic and engineering development

The author has identified the following significant results. Hydrologic inventories, throughout the year, were made in interior basins that have not been measured previously because of their inaccessibility. Interior basins during the last ERTS-1 year (August 1972 to August 1973) had driest ground conditions in late September 1972 and had wettest ground conditions from March through May 1973, depending upon location. Bearing strengths of playa soils can be inferred from the changing hydrologic conditions through the seasons as recorded by ERTS-1, with prior ground control. Slight differences in salt-crust morphology and in moisture contest of playa soils can be greatly enhanced by rationing and stretching techniques. Differences in water area and silt content can be enhanced by using a three-stage photographic masking technique employing bands 4, 5, and 7.

Krinsley, D. B.↗

DOE OSTI2022

Automated exploitation of the big configuration space of large adsorbates on transition metals reveals chemistry feasibility

Mechanistic understanding of large molecule conversion and the discovery of suitable heterogeneous catalysts have been lagging due to the combinatorial inventory of intermediates and the inability of humans to enumerate all structures. Here, we introduce an automated framework to predict stable configurations on transition metal surfaces and demonstrate its validity for adsorbates with up to 6 carbon and oxygen atoms on 11 metals, enabling the exploration of ~10 8 potential configurations. It combines a graph enumeration platform, force field, multi-fidelity DFT calculations, and first-principles trained machine learning. Clusters in the data reveal groups of catalysts stabilizing different structures and expose selective catalysts for showcase transformations, such as the ethylene epoxidation on Ag and Cu and the lack of C-C scission chemistry on Au. Deviations from the commonly assumed atom valency rule of small adsorbates are also manifested. This library can be leveraged to identify catalysts for converting large molecules computationally.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

NASA NTRS1994

Neodymium, strontium and chromium isotopic studies of the LEW86010 and Angra dos Reis meteorites and the chronology of the angrite parent body

Neodymium, stontium, and chromium isotopic studies of the LEW86010 angrite established its absolute age and the formation interval between its crystallization and condensation of Allende CAIs from the solar nebula. Pyroxene and phosphate were found to contain approximately 8% of its Sm and Nd inventory. A conventional Sm-147-Nd-143 isochron yielded an age of 4.53 +/- 0.04 Ga (2 sigma and Epsilon(sub Nd sup 143)) = 0.45 +/- 1.1. An Sm-146-Nd-142 isochron gives initial Sm-146/Sm-144 = 0.0076 +/- 0.0009 and Epsilon (sub Nd sup 142) = -2.5 +/- 0.4. The Rb-Sr analyses give initial Sr-87/Sr-86 Iota(sub Sr sup 87) = 0.698972 +/- 8 and 0.698970 +/- 18 for LEW and ADOR, respectively, relative to Sr-87/Sr-86 = 0.71025 for NBS987. The difference, Delta Iota(sub Sr Sup 87), between Iota (sub sr sup 87) for the angrites and literature values for Allende CAIs, corresponds to approximately Ma of growth in a solar nebula with a CI chondrite value of Rb-87/Sr-86 = 0.91, or approximately 5 Ma in a nebula with solar photospheric Rb-87/Sr-86 = 1.51. Excess Cr-53 from extinct Mn-53(t(sub 1/2) = 3.7 Ma)in LEW86010 corresponds to initial Mn-53/Mn-55 = 4.4 +/- 1.0 x 10(exp -5) for the inclusions as previously reported by the Paris group (Birck and Allegre, 1988). The Sm-146/Sm-144 value found for LEW86010 corresponds to solar system initial (Sm-146/Sm-144) = 0.0080 +/- 0.0009 for crystallization 8 Ma after Allende, the difference between Pb-Pb ages of angrites and Allende, or 0.0086 +/- 0.0009 for crystallation 18 Ma after Allende, using the Mn-Cr formation interval. The isotopic data are discussed in the context of a model in which an undifferentiated 'chondritic' parent body formed from the solar nebula approximately Ma after Allende CAIs and subsequently underwent differentiation accompanied by loss of volatiles. Parent bodies with Rb/Sr similar to that of CI, CM, or CO chondrites could satisfy the Cr and Sr isotopic systematics. If the angrite parent body had Rb/Sr similar to that of CV meteorites, it would have to form slightly later, approximately 2.6 Ma after the CAIs, to satisfy the Sr and CR isotopic systematics.

Nyquist, L. E.↗

NASA NTRS1993

Orbital performance of communication satellite microwave power amplifiers (MPAs)

This paper presents background data on the performance of microwave power amplifiers (MPAs) used as transmitters in currently operating commercial communication satellites. Specifically aspects of two competing MPA types are discussed. These are well known TWTA (travelling wave tube amplifier) and the SSPA (solid state power amplifier). Extensive in-orbit data has been collected from over 2000 MPAs in 1991 and 1993. The study in 1991 invovlved 75 S/C (spacecraft) covering 463 S/C years. The 1993 'second-look' study encompassed a slightly different population of 72 S/C with 497 S/C years of operation. A surprising result of both studies was that SSPAs, although quite reliable, did not achieve the reliability of TWTAs were one-third more reliable in the 1993 study. This was at C-band with comparable power amplifiers, e.g. 6-16W of RF output power and similar gains. Data at K(sub u)-band is for TWTAs only since there are no SSPAs in the current S/C inventory. The other complementary result was that the projected failure rates used as S/C payload design guidelines were, on average, somewhat higher for TWTAs than the actual failure rates uncovered by this study. SSPA rates were as projected.

Strauss, R.↗

NASA NTRS2005

Heat Pipe Reactor Dynamic Response Tests: SAFE-100 Reactor Core Prototype

The SAFE-I00a test article at the NASA Marshall Space Flight Center was used to simulate a variety of potential reactor transients; the SAFEl00a is a resistively heated, stainless-steel heat-pipe (HP)-reactor core segment, coupled to a gas-flow heat exchanger (HX). For these transients the core power was controlled by a point kinetics model with reactivity feedback based on core average temperature; the neutron generation time and the temperature feedback coefficient are provided as model inputs. This type of non-nuclear test is expected to provide reasonable approximation of reactor transient behavior because reactivity feedback is very simple in a compact fast reactor (simple, negative, and relatively monotonic temperature feedback, caused mostly by thermal expansion) and calculations show there are no significant reactivity effects associated with fluid in the HP (the worth of the entire inventory of Na in the core is .<el, so fluid movement and temperature changes will cause very minor effects). In previous SAFE-100 tests, the point kinetics model was based on core thermal expansion via deflection measurements. It was found that core deflection was a strung function of how the SAFE-100 modules were fabricated and assembled (in terms of straightness, gaps, and other tolerances). To remove the added variable of how this particular core expands as compared to a different concept, it was decided to use a temperature based feedback model (based on several thermocouples placed throughout the core).

Bragg-Sitton, Shannon M.↗

NASA NTRS2001

Scheduled Civil Aircraft Emission Inventories for 1999: Database Development and Analysis

This report describes the development of a three-dimensional database of aircraft fuel burn and emissions (NO(x), CO, and hydrocarbons) for the scheduled commercial aircraft fleet for each month of 1999. Global totals of emissions and fuel burn for 1999 are compared to global totals from 1992 and 2015 databases. 1999 fuel burn, departure and distance totals for selected airlines are compared to data reported on DOT Form 41 to evaluate the accuracy of the calculations. DOT Form T-100 data were used to determine typical payloads for freighter aircraft and this information was used to model freighter aircraft more accurately by using more realistic payloads. Differences in the calculation methodology used to create the 1999 fuel burn and emissions database from the methodology used in previous work are described and evaluated.

Sutkus, Donald J., Jr.↗

DOE OSTI2023

On falling film evaporator – A review of mechanisms and critical assessment of correlation on a horizontal tube bundle with updated development

Optimization of the energy efficiency and reduction of the greenhouse gas emission for the heat pump system is imperative to meet the net-zero goals at 2050. Chillers with falling film evaporator design not only possess better system performance but also contain less refrigerant inventory. Hence, accurate prediction of the evaporator performance is pivotal especially when charged with low-GWP refrigerant. Here, the study reviews the correlations for falling film evaporator with a horizontal tube bundle configuration. The major efforts of this study include four tasks: (a) literature review of the experimental studies and available empirical correlations; (b) comprehensive discussion of the falling film evaporation heat transfer mechanism; (c) development of a new rationally based correlation based on available literature; and (d) comparison of different correlations based on the existing data. The collected data includes 4114 data points from 8 sources, 6 refrigerants (R-600a, R-290, R-245fa, R-134a, R-1234ze(E), R-123), 5 types of the tubes (Plain, Turbo-GII-HP, GEWA-B, Low-fin, High-Flux), liquid Weber number from 2.2 × 10 –6 to 0.7, imposed vapor Weber number from 0 to 37.2, heat flux from 2.5 to 151.5 kW/m 2 , and film Reynolds number from 1 to 3159.8. The new correlation gives a MAD of 28.3%, and an R 2 of 0.86. Yet, the developed correlation considers various heat transfer mechanisms, including the transition point from falling film evaporation to the nucleate boiling, local evaporation, dry-out, mist flow, imposed flow, and enhanced tube effects.

42 ENGINEERING↗

DOE OSTI2022

Variation in carbon and nitrogen concentrations among peatland categories at the global scale

Peatlands account for 15 to 30% of the world’s soil carbon (C) stock and are important controls over global nitrogen (N) cycles. However, C and N concentrations are known to vary among peatlands contributing to the uncertainty of global C inventories, but there are few global studies that relate peatland classification to peat chemistry. We analyzed 436 peat cores sampled in 24 countries across six continents and measured C, N, and organic matter (OM) content at three depths down to 70 cm. Sites were distinguished between northern (387) and tropical (49) peatlands and assigned to one of six distinct broadly recognized peatland categories that vary primarily along a pH gradient. Peat C and N concentrations, OM content, and C:N ratios differed significantly among peatland categories, but few differences in chemistry with depth were found within each category. Across all peatlands C and N concentrations in the 10–20 cm layer, were 440 ± 85.1 g kg -1 and 13.9 ± 7.4 g kg -1 , with an average C:N ratio of 30.1 ± 20.8. Among peatland categories, median C concentrations were highest in bogs, poor fens and tropical swamps (446–532 g kg -1 ) and lowest in intermediate and extremely rich fens (375–414 g kg -1 ). The C:OM ratio in peat was similar across most peatland categories, except in deeper samples from ombrotrophic tropical peat swamps that were higher than other peatlands categories. Peat N concentrations and C:N ratios varied approximately two-fold among peatland categories and N concentrations tended to be higher (and C:N lower) in intermediate fens compared with other peatland types. This study reports on a unique data set and demonstrates that differences in peat C and OM concentrations among broadly classified peatland categories are predictable, which can aid future studies that use land cover assessments to refine global peatland C and N stocks.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2023

Cradle-to-Gate Life Cycle Analysis Baseline for United States Coal Mining and Delivery

The goal of this study is to highlight the environmental impacts from upstream coal production to its delivery at a power plant. This study is meant to characterize different coal basins, coal types, and mine types used to produce electric power in the North American Electric Reliability Corporation (NERC) regions in the United States using a functional unit of 1 kg of coal. The boundary of this study includes underground or surface extraction, water use at the mine, ventilation, coal handling, coal cleaning, mine tailing disposal, and transportation via conveyer belt, truck, ocean vessel, barge, and train. See the following URLs for accompanying documents: NETL Coal Baseline Model - Transportation Inventories: https://www.netl.doe.gov/energy-analysis/details?id=27ea1ba4-6ea9-4ee5-8b32-d7fce7f4e1e0. NETL Coal Baseline Model - Basin Inventories: https://www.netl.doe.gov/energy-analysis/details?id=0f290eed-5e4b-4b5f-bec0-36b0ea89c6e5. NETL Coal Baseline Model - Excel file: https://www.netl.doe.gov/energy-analysis/details?id=0dc18730-4214-4878-8a0f-d1941c45123c. NETL Coal Baseline Model - Open LCA model: https://www.netl.doe.gov/energy-analysis/details?id=0c0dde04-0d3c-4c7f-bd33-2745e061b8e0.

01 COAL, LIGNITE, AND PEAT↗

NASA NTRS2002

Amino acids in the Tagish Lake Meteorite

High-performance liquid chromatography (HPLC) based amino acid analysis of a Tagish Lake meteorite sample recovered 3 months after the meteorite fell to Earth have revealed that the amino acid composition of Tagish Lake is strikingly different from that of the CM and CI carbonaceous chondrites. We found that the Tagish Lake meteorite contains only trace levels of amino acids (total abundance = 880 ppb), which is much lower than the total abundance of amino acids in the CI Orgueil (4100 ppb) and the CM Murchison (16 900 ppb). Because most of the same amino acids found in the Tagish Lake meteorite are also present in the Tagish Lake ice melt water, we conclude that the amino acids detected in the meteorite are terrestrial contamination. We found that the exposure of a sample of Murchison to cold water lead to a substantial reduction over a period of several weeks in the amount of amino acids that are not strongly bound to the meteorite matrix. However, strongly bound amino acids that are extracted by direct HCl hydrolysis are not affected by the leaching process. Thus even if there had been leaching of amino acids from our Tagish Lake meteorite sample during its 3 month residence in Tagish Lake ice and melt water, a Murchison type abundance of endogenous amino acids in the meteorite would have still been readily detectable. The low amino acid content of Tagish Lake indicates that this meteorite originated fiom a different type of parent body than the CM and CI chondrites. The parent body was apparently devoid of the reagents such as aldehyldes/ketones, HCN and ammonia needed for the effective abiotic synthesis of amino acids. Based on reflectance spectral measurements, Tagish Lake has been associated with P- or D-type asteroids. If the Tagish Lake meteorite was indeed derived fiom these types of parent bodies, our understanding of these primitive asteroids needs to be reevaluated with respect to their potential inventory of biologically important organic compounds.

Kminek, G.↗

DOE OSTI2017

A French Industrial Management Plan for Very Low Level Radioactive Wastes (VLLW) at the CIRES Facility - 17012

Since 2003, very-low-level waste has been disposed of at the Andra CIRES disposal facility, the first disposal facility in the world for this type. It is now the main route in terms of volumes for the management of French radioactive waste. The 2015 national inventory has identified 1.1 million m{sup 3} of VLLW to be produced until 2030. Several waste management scenarios were then analyzed, including issues associated with the flow reduction of the waste to be stored. The key avenues to reduce the volumes of waste, technical and economic viability of which still needing to be challenged, are at this stage: - Favor the reuse of large amounts of metallic VLLW to be produced within the next decade. - To service the recycling of metals, different opportunities for reuse should be considered -including within the non-nuclear sector. - 30% to 50% of VLLW produced in the so-called 'nuclear waste' areas probably have zero or non-detectable radioactivity levels and questions about the introduction of a clearance level. - A disposal route based on a concept derived from waste storage facility for non-nuclear and non-hazardous wastes could be an alternative to the clearance level for the least active inert waste. Therefore volumetric optimizations appear possible, even if the waste management costs will be higher than the current route. Furthermore, efficiency gains and progresses in operating modes would increase the technical capacity of the CIRES of about 250 000 m{sup 3}. In all cases studied, it appears essential to create around 2030 a new VLLW disposal facility, particularly for the dismantling of the current fleet of reactors. According to the proposed optimizations, the necessary capacity for a second VLLW disposal facility would range between 600 000 m{sup 3} and 1.2 million m{sup 3}. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

NASA NTRS1979

The use of spectral data in wheat yield estimation - An assessment of techniques explored in LACIE

The object of the paper is to assess the results of the Large Area Crop Inventory Experiment (LACIE) and closely related research on yield estimation techniques based on remote sensing variables. The exploratory research conducted during LACIE substantiated the hypothesis of yield related information contained in Landsat multispectral scanner data and indicated some of its empirical characteristics. It is noted that leaf area and possibly other foliage features can be derived from spectral data for yield estimation through agrometeorological models and that multiple vegetative and grain related features may be discernable by Landsat derived wheat spectra at different points in the crop development.

Stuff, R. G.↗

NASA NTRS1989

Adjustment of sleep and the circadian temperature rhythm after flights across nine time zones

The adjustment of sleep-wake patterns and the circadian temperature rhythm was monitored in nine Royal Norwegian Airforce volunteers operating P-3 aircraft during a westward training deployment across nine time zones. Subjects recorded all sleep and nap times, rated nightly sleep quality, and completed personality inventories. Rectal temperature, heart rate, and wrist activity were continuously monitored. Adjustment was slower after the return eastward flight than after the outbound westward flight. The eastward flight produced slower readjustment of sleep timing to local time and greater interindividual variability in the patterns of adjustment of sleep and temperature. One subject apparently exhibited resynchronization by partition, with the temperature rhythm undergoing the reciprocal 15-h delay. In contrast, average heart rates during sleep were significantly elevated only after westward flight. Interindividual differences in adjustment of the temperature rhythm were correlated with some of the personality measures. Larger phase delays in the overall temperature waveform (as measured on the 5th day after westward flight) were exhibited by extraverts, and less consistently by evening types.

Gander, Philippa H.↗

NASA NTRS2023

Learnings From Rapid Response Efforts to Remotely Detect Landslides Triggered By the August 2021 Nippes Earthquake and Tropical Storm Grace in Haiti

On August 14, 2021, a Mw 7.2 earthquake struck the Tiburon Peninsula of western Haiti triggering thousands of landslides. Three days after the earthquake on August 17, 2021, Tropical Storm Grace crossed shallow waters offshore of southern Haiti triggering more landslides worsening the situation. In the aftermath of these events, several organizations with disaster response capabilities or programs activated to provide information on the location of landslides to first responders on the ground. Utilizing remote sensing to support rapid response, one organization manually mapped initiation point of landslides and three automatically detected landslides. The 2021 Haiti event also provided a unique opportunity to test different automated landslide detection methods that utilized both SAR and optical data in a rapid response scenario where rapid situational awareness was critical. As the methods used are highly replicable, the main goal of this study is to summarize the landslide rapid response products released by the organizations, detection methods, quantify accuracy and provide guidelines on how some of the shortcomings encountered in this effort might be addressed in the future. To support this validation, a manually mapped polygon-based landslide inventory covering the entire affected area was created and is also released through this effort.

2021 Nippes earthquake↗

DOE OSTI2020

ASGS - An Innovative Approach for Waste Characterization - From the First Study to Experimental Validation - 20260

For disposal of nuclear waste a clear identification of the nuclear inventory is mandatory. Since this waste is usually filled in drums, nuclear specific characterization methods using HPGe detectors usually require the understanding of the limitations of the method assumptions (such as the homogeneity criteria), and often results in applying high uncertainties to the result in waste that is not well known a priori. There are several methods and approaches such as Far-Field, Segmented Gamma Scans (SGS) or Tomographic Gamma Scans (TGS) available. The SGS allows measuring the waste drum in different segments (or 'layers') which allows getting more detailed information about the activity distribution inside a waste drum. In addition, with the transmission source used in tomographic scans, it is possible to also determine the material (and its homogeneity) composition inside a drum. Mirion Technologies developed in cooperation with Aachen Institute for Nuclear Training (AiNT) an innovative measurement approach which allows more accurate results and therefore applying lower uncertainties. This new measurement approach extends the concept of SGS by partitioning the drum into single drum sectors instead of segments. The goal is to perform measurements with high throughput and an accurate analysis based on the reconstruction of activities for each sector. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2026

Understanding carbon sourcing and transport originating from the helicon antenna surfaces during high-power helicon discharge in DIII-D Tokamak

The high-power helicon wave system in the DIII-D tokamak could potentially introduce new plasma–material interaction (PMI) challenges owing to rectified RF sheath potentials that develop near the antenna and surrounding plasma-facing components. We present the first application of the STRIPE (Simulated Transport of RF Impurity Production and Emission) framework to helicon-induced PMIs, extending previous STRIPE studies of ICRH antennas by incorporating net erosion, local re-deposition, and three-dimensional global impurity transport. The integrated workflow couples SOLPS, COMSOL, RustBCA, GITR, and GITRm to simulate carbon erosion, re-deposition, and impurity transport for two experimentally constrained DIII-D H-mode helicon operating scenarios with different antenna–plasma gaps, coupled RF powers, and edge plasma conditions. COMSOL predicts rectified RF sheath potentials of 1–5 kV localized near the lower portion of the antenna, where the magnetic field intersects the surface at grazing incidence. Carbon self-sputtering dominates the erosion source, whereas RF-accelerated D + ions contribute approximately 1% of the total gross erosion. The smaller-gap operating scenario exhibits substantially stronger gross erosion, enhanced local re-deposition (∼12%), and a larger confined carbon inventory owing to increased plasma accessibility and broader RF sheath coverage. Comparison with available DIII-D measurements shows no distinct change in the global carbon signal that correlates with the helicon RF pulse, consistent with the simulations indicating that the helicon-generated carbon source remains small compared with the existing background carbon inventory under the present graphite-wall operating conditions. These results demonstrate the capability of STRIPE to integrate RF sheath modeling, plasma transport, surface interaction physics, and three-dimensional impurity transport for the interpretation of helicon-induced PMIs. The study further identifies the principal sources of modeling uncertainty, including grazing-angle RF sheath physics, slow-wave resolution, plasma-background extrapolation, and trace-impurity transport assumptions, providing a framework for future validation and model development.

Kumar, Atul [Oak Ridge National Laboratory (ORNL),↗

DOE OSTI2021

Annual Status Update for OWL

This report represents completion of milestone deliverable M2SF-22SN010309082 Annual Status Update for OWL, which is due on November 30, 2021 as part of the fiscal year 2022 (FY2022) work package SF-22SN01030908. This report provides an annual update on status of FY2021 activities for the work package “OWL - Inventory – SNL”. The Online Waste Library (OWL) has been designed to contain information regarding United States (U.S.) Department of Energy (DOE)-managed (as) high-level waste (DHLW), DOE-managed spent nuclear fuel (DSNF), and other wastes that are likely candidates for deep geologic disposal. Links to the current supporting documents for the data are provided when possible; however, no classified or official-use-only (OUO) data are planned to be included in OWL. There may be up to several hundred different DOE-managed wastes that are likely to require deep geologic disposal. This report contains new information on sodium-bonded spent fuel waste types and wastes forms, which are included in the next release of OWL, Version 3.0, on the Sandia National Laboratories (SNL) External Collaboration Network (ECN). The report also provides an update on the effort to include information regarding the types of vessels capable of disposing of DOE-managed waste.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗