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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 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Solvent Hold Tank Sample Results for MCU-18-301- 303 (July 2018), MCU-18-357-359-360 (August 2018), and MCU-18-402-410 (September 2018) (Quarterly Report)

A trend summary of three Solvent Hold Tank (SHT) monthly samples; MCU-18-301-302-303, MCU-18- 357-359-360 and MCU-18-402-410 are reported. Most of the conclusions are based on the September SHT sample (MCU-18-402-410). Analyses of the September SHT sample (MCU-18-402-410) indicated that the Modifier (Cs-7SB) and the extractant (MaxCalix) concentrations were below their nominal recommended concentrations (169,000 mg/L and 46,400 mg/L respectively) by 5% and 8% respectively. The suppressor (N,N’,N”–tris(3,7-dimethyloctyl)guanidine or TiDG) concentration has decreased since the April 2018 measurement (Modular Caustic-Side Solvent Extraction Unit or MCU resumed processing radioactive salt solution from May through August 2018) to 241 mg/L, well below the minimum recommended concentration (479 mg/L). The apparent “downwards” trends observed in the TiDG, MaxCalix, and Modifier measurements are consistent with the startup (or Proficiency Runs) of MCU on May 22, 2018; new levels are consistent with the concentrations observed when MCU was fully operational in 2016. This analysis confirms the Isopar™ L addition to the solvent on July 2 and August 9, 2018. This analysis also indicates the solvent did require a trim addition. Based on the current monthly sample, the concentrations of Isopar™ L, MaxCalix, and Modifier are sufficient for continuing operation but are expected to decrease with time. The TiDG concentration was below its recommended level. Periodic characterization and trimming additions to the solvent are recommended. The Semi-Volatile Organic Analysis (SVOA) did not detect any impurities. However, the Fourier Transform Hydrogen Nuclear Magnetic Resonance (FT-HNMR) analysis detected a low concentration of sec-butyl phenol (SBP) at levels of a few ppm. The impurity concentration was highest in the July sample and consistently detected in the August and September samples (but always a few ppm or less). The source of this impurity is due to the degradation of the Modifier. Another impurity observed in the samples was mercury. Based on the September SHT sample, up to 17 ± 3 micrograms of mercury per mL of solvent was detected (the average of the Direct Mercury Analysis (DMA) and X-Ray Fluorescence (XRF) methods). The higher mercury concentration in the solvent (as determined in the last three monthly samples) is possibly due to the higher mercury concentration in Salt Batches 9 and 10 (SB 10 was recently added to Tank 49H in March 2017). The gamma concentration (~2.3E5 dpm/mL) measured in the September SHT samples was consistent with previous values observed when MCU was fully operational (for example, between December 2016 and January 2017) and it was lower than the April SHT measurement. The “dip” in the gamma measurement for the May 2018 SHT sample was due to Isopar™ L addition to MCU during April and May 2018. The laboratory will continue to monitor the quality of the solvent for any new impurities or degradation of the solvent components.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Solvent Hold Tank Sample Results for MCU-18-425- 427 (October 2018), MCU-18-459-460-461 (November 2018), and MCU-18-487-488-489 (December 2018) (Quarterly Report)

A trend summary of three Solvent Hold Tank (SHT) monthly samples MCU-18-425-426-427, MCU-18- 459-460-461 and MCU-18-487-488-489 are reported. Most of the conclusions are based on the December SHT sample (MCU-18-487-488-489). Analyses of the December SHT sample (MCU-18-487-488-489 indicated that the Modifier (Cs-7SB) and the extractant (MaxCalix) concentrations were below their nominal recommended concentrations (169,000 mg/L and 46,400 mg/L respectively) by 2% and 9% respectively. The suppressor (N,N’,N”–tris(3,7-dimethyloctyl)guanidine or TiDG) concentration has decreased since the October 2018 measurement (Modular Caustic-Side Solvent Extraction Unit or MCU resumed processing (from May through November 2018) to 528 mg/L, but it is above the minimum recommended concentration (479 mg/L). These new levels are consistent with the concentrations observed when MCU was fully operational in 2016. The Semi-Volatile Organic Analysis (SVOA) did not detect any impurities. However, the Fourier Transform Hydrogen Nuclear Magnetic Resonance (FT-HNMR) analysis detected presence of phthalates at a few ppm. The impurity concentration was highest in the October sample and consistently detected in the November and December samples (but always a few ppm or less). Another impurity observed in the samples was mercury. Based on the December SHT sample, up to 24 ± 5 micrograms of mercury per mL of solvent was detected (as the average of the Direct Mercury Analysis (DMA) and X-Ray Fluorescence (XRF) methods). The higher mercury concentration in the solvent (as determined in the last three-monthly samples) is possibly due to the higher mercury concentration in Salt Batches 9 and 10. The gamma concentration (~3.6E5 dpm/mL) measured in the December SHT samples was consistent with previous values observed when MCU was fully operational (for example, between December 2016 and January 2017) but it was lower than the April SHT measurement. The “dip” in the gamma measurement for the May 2018 SHT sample was due to an Isopar™ L addition to MCU during April and May 2018. The laboratory will continue to monitor the quality of the solvent for any new impurities or degradation of the solvent components.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Solvent Hold Tank Sample Results for MCU-18-123- 125 (April 2018), MCU-18-135-137 (May 2018), and MCU-18-192-197(June 2018): Quarterly Report

A trend summary of three Solvent Hold Tank (SHT) monthly samples MCU-18-123-125, MCU-18-135- 137, and MCU-18-192-197 are reported. Most of the conclusions are based on the June SHT sample (MCU- 18-192-197). Analyses of the June SHT sample (MCU-18-192-197) indicated that the Modifier (CS-7SB) and the extractant (MaxCalix) concentrations were at the nominal recommended concentrations (169,000 mg/L and 46,400 mg/L respectively). The suppressor ( N,N’,N” –tris(3,7-dimethyloctyl)guanidine or TiDG) concentration has decreased since the April 2018 measurement (Modular Caustic-Side Solvent Extraction Unit or MCU resumed processing radioactive salt solution from May through August 2018) to 1,116 mg/L, well above the minimum recommended concentration (479 mg/L), but below the nominal concentration. The apparent “downwards” trends observed in the TiDG, MaxCalix, Modifier, and gamma measurement are consistent with the start up (and/or proficiency runs) of MCU on May 22, 2018 since these new concentrations are consistent with the concentrations observed when MCU was fully operational in 2016.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

Constraints on Λ CDM extensions from the SPT-3G 2018 $EE$ and $TE$ power spectra

Here, we present constraints on extensions to the Λ CDM cosmological model from measurements of the E-mode polarization autopower spectrum and the temperature-E-mode cross-power spectrum of the cosmic microwave background (CMB) made using 2018 SPT-3G data. The extensions considered vary the primordial helium abundance, the effective number of relativistic degrees of freedom, the sum of neutrino masses, the relativistic energy density and mass of a sterile neutrino, and the mean spatial curvature. We do not find clear evidence for any of these extensions, from either the SPT-3G 2018 dataset alone or in combination with baryon acoustic oscillation and Planck data. None of these model extensions significantly relax the tension between Hubble-constant, H 0 , constraints from the CMB and from distance-ladder measurements using Cepheids and supernovae. The addition of the SPT-3G 2018 data to Planck reduces the square-root of the determinants of the parameter covariance matrices by factors of 1.3–2.0 across these models, signaling a substantial reduction in the allowed parameter volume. We also explore CMB-based constraints on H 0 from combined SPT, Planck, and ACT DR4 datasets. While individual experiments see some indications of different H 0 values between the TT, TE, and EE spectra, the combined H 0 constraints are consistent between the three spectra. For the full combined datasets, we report H 0 = 67.49 ± 0.53 km s -1 Mpc -1 , which is the tightest constraint on H0 from CMB power spectra to date and in 4.1σ tension with the most precise distance-ladder-based measurement of H 0 . The SPT-3G survey is planned to continue through at least 2023, with existing maps of combined 2019 and 2020 data already having ~ 3.5 x lower noise than the maps used in this analysis.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2019

Temperature of the Troposphere [in State of the Climate in 2018]

The 2018 annual global lower troposphere temperature (LTT; surface to ~10km) ranked third to seventh highest as monitored by radiosondes since 1958 and satellites since 1979 according to nine datasets examined for this analysis. (As noted in Section 2b1, the 2018 global average surface temperature was fourth highest.) A weak La Niña event extending into early 2018 suppressed the global LTT in the 2018 boreal winter and spring. In comparison, the tropical Pacific exhibited higher-than-average temperatures in boreal autumn, indicating the eventual initiation of a weak El Niño at the end of 2018 that contributed to higher-than-average temperatures in the following seasons in 2019. Among the nine datasets, the 2018 anomaly ranged from +0.23°C to +0.47°C relative to the 1981–2010 average and was ~0.3°C lower than the record warm year of 2016.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

CY2018 Annual Closure Monitoring Report for Corrective Action Unit 98, Frenchman Flat, Underground Test Area, Nevada National Security Site, Nevada (January 2018–December 2018, Revision 1)

Corrective Action Unit (CAU) 98: Frenchman Flat on the Nevada National Security Site was the location of 10 underground nuclear tests. CAU 98 underwent a series of investigations and actions in accordance with the Federal Facility Agreement and Consent Order to assess contamination of groundwater by radionuclides from the tests. A Closure Report completed that process in 2016 and called for long-term monitoring, use restrictions (URs), and institutional controls to protect the public and environment from potential exposure to contaminated groundwater. Three types of monitoring are performed for CAU 98: water quality, water level, and institutional control. These are monitored to determine whether the URs remain protective of human health and the environment, and to ensure that the regulatory boundary objectives are being met. Monitoring data will be used in the future, once multiple years of data are available, to evaluate consistency with the groundwater flow and contaminant transport models because the contaminant boundaries calculated with the models are the primary basis of the UR boundaries. Six wells were sampled for water-quality monitoring in 2018. Contaminants of concern were detected only in the two source/plume wells already known to contain contamination as a result of a radionuclide migration experiment. Tritium concentrations in both of these wells, RNM-2S and UE-5n, remain above the Safe Drinking Water Act maximum contaminant level of 20,000 picocuries per liter but declined in 2018 as compared to measurements in 2017. All other contaminants of concern are below the minimum detection level plus analytical error. The water-level monitoring network includes 16 wells. Depth to water measured in 2018 is generally consistent with recent measurements for all wells. Many wells continue to exhibit a long-term downward trend in water level, despite small increases in measured water levels in 2018. The sharp 2016 decline in water level in Well ER-5-3-2 remains unexplained, with the lower level persisting through 2018. Rising water-level trends continue to be observed in two relatively deep wells (ER-5-3 deep piezometer and ER-5-4-2), and also in former supply Well WW-5A. The current supply wells exhibit relatively erratic water levels associated with pumping activities. Institutional control monitoring confirmed the URs are recorded in U.S. Department of Energy and U.S. Air Force land management systems, and that no activities within Frenchman Flat basin are occurring that could potentially affect the contaminant boundaries. Survey of groundwater resources in basins surrounding Frenchman Flat similarly identify no current or pending development that would indicate the need to increase monitoring activities or would otherwise cause concern for the closure decision. The URs continue to prevent exposure of the public, workers, and the environment to contaminants of concern by preventing use of potentially contaminated groundwater.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Measurements of the E-mode polarization and temperature-E-mode correlation of the CMB from SPT-3G 2018 data

We present measurements of the E -mode ( E E ) polarization power spectrum and temperature- E -mode ( T E ) cross-power spectrum of the cosmic microwave background using data collected by SPT-3G, the latest instrument installed on the South Pole Telescope. This analysis uses observations of a 1500 deg 2 region at 95, 150, and 220 GHz taken over a four-month period in 2018. We report binned values of the E E and T E power spectra over the angular multipole range 300 ≤ ℓ < 3000 , using the multifrequency data to construct six semi-independent estimates of each power spectrum and their minimum-variance combination. These measurements improve upon the previous results of SPTpol across the multipole ranges 300 ≤ ℓ ≤ 1400 for E E and 300 ≤ ℓ ≤ 1700 for T E , resulting in constraints on cosmological parameters comparable to those from other current leading ground-based experiments. We find that the SPT-3G data set is well fit by a Λ CDM cosmological model with parameter constraints consistent with those from Planck and SPTpol data. From SPT-3G data alone, we find H 0 = 68.8 ± 1.5 km s - 1 Mpc - 1 and σ 8 = 0.789 ± 0.016 , with a gravitational lensing amplitude consistent with the Λ CDM prediction ( A L = 0.98 ± 0.12 ). We combine the SPT-3G and the Planck data sets and obtain joint constraints on the Λ CDM model. The volume of the 68% confidence region in six-dimensional Λ CDM parameter space is reduced by a factor of 1.5 compared to Planck-only constraints, with no significant shifts in central values. We note that the results presented here are obtained from data collected during just half of a typical observing season with only part of the focal plane operable, and that the active detector count has since nearly doubled for observations made with SPT-3G after 2018.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2019

Foothill Transit Agency Battery Electric Bus Progress Report, Data Period Focus: Jul. 2018 through Dec. 2018

This report summarizes results of a battery electric bus (BEB) evaluation at Foothill Transit, located in the San Gabriel Valley area of Los Angeles. Foothill Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. The focus of this evaluation is to compare the performance and the operating costs of the BEBs to that of conventional technology buses and to track progress over time. Previous reports documented results from April 2014 through June 2018. This report extends the data analysis through the end of 2018. The data period focus of this report is July 2018-December 2018. NREL plans to publish progress reports on the Foothill Transit fleet every 6 months through 2020.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2019

Proceedings of The Magnificent CEνNS Workshop 2018

The Magnificent CE$\nu$NS Workshop (2018) was held November 2 & 3 of 2018 on the University of Chicago campus and brought together theorists, phenomenologists, and experimentalists working in numerous areas but sharing a common interest in the process of coherent elastic neutrino-nucleus scattering (CE$\nu$NS). This is a collection of abstract-like summaries of the talks given at the meeting, including links to the slides presented. This document and the slides from the meeting provide an overview of the field and a snapshot of the robust CE$\nu$NS-related efforts both planned and underway.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Los Alamos National Laboratory 2018 Monitoring Season for storm water and atmospheric deposition samples from Bandelier National Monument under Permit # BAND-2018-SCI-0006 - 2018 Monitoring Season Summary

Los Alamos National Laboratory (LANL) completed the 2018 monitoring season for a multi-year monitoring project to characterize background/baseline conditions around and distal to the Pajarito Plateau, Northern New Mexico. The following media were included in the 2018 monitoring season: precipitation, storm water, and atmospheric deposition. Data generated in this study will be used to characterize and quantify the impacts to water quality from natural background sediments and atmospheric deposition of persistent organic pollutants such as polychlorinated biphenyls [PCBs]. Details specific to 2018 monitoring season are presented below.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Foothill Transit Agency Battery Electric Bus Progress Report, Data Period Focus: Jan. 2018 through Jun. 2018

This report summarizes results of a battery electric bus (BEB) evaluation at Foothill Transit, located in the San Gabriel Valley area of Los Angeles. Foothill Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to evaluate the buses in revenue service. The focus of this evaluation is to compare the performance and the operating costs of the BEBs to that of conventional technology buses and to track progress over time. Previous reports documented results from April 2014 through December 2017. This report extends the data analysis through June 2018. NREL plans to publish progress reports on the Foothill Transit fleet every six months through 2020. performance and the operating costs of the BEBs to that of conventional technology buses and to track progress over time. Previous reports documented results from April 2014 through December 2017. This report extends the data analysis through June 2018. NREL plans to publish progress reports on the Foothill Transit fleet every six months through 2020.

33 ADVANCED PROPULSION SYSTEMS↗
NASA NTRS2023

Satellite Remote-Sensing Capability to Assess Tropospheric-Column Ratios of Formaldehyde and Nitrogen Dioxide: Case Study During the Long Island Sound Tropospheric Ozone Study 2018 (LISTOS 2018) Field Campaign

Satellite retrievals of tropospheric-column formaldehyde (HCHO) and nitrogen dioxide (NO 2 ) are frequently used to investigate the sensitivity of ozone (O 3 ) production to emissions of nitrogen oxides and volatile organic carbon compounds. This study inter-compared the systematic biases and uncertainties in retrievals of NO 2 and HCHO, as well as resulting HCHO–NO 2 ratios (FNRs), from two commonly applied satellite sensors to investigate O 3 production sensitivities (Ozone Monitoring Instrument, OMI, and TROPOspheric Monitoring Instrument, TROPOMI) using airborne remote-sensing data taken during the Long Island Sound Tropospheric Ozone Study 2018 between 25 June and 6 September 2018. Compared to aircraft-based HCHO and NO 2 observations, the accuracy of OMI and TROPOMI were magnitude-dependent with high biases in clean environments and a tendency towards more accurate comparisons to even low biases in moderately polluted to polluted regions. OMI and TROPOMI NO 2 systematic biases were similar in magnitude (normalized median bias, NMB = 5 %–6 %; linear regression slope ≈ 0.5–0.6), with OMI having a high median bias and TROPOMI resulting in small low biases. Campaign-averaged uncertainties in the three satellite retrievals (NASA OMI; Quality Assurance for Essential Climate Variables, QA4ECV OMI; and TROPOMI) of NO 2 were generally similar, with TROPOMI retrievals having slightly less spread in the data compared to OMI. The three satellite products differed more when evaluating HCHO retrievals. Campaign-averaged tropospheric HCHO retrievals all had linear regression slopes ∼0.5 and NMBs of 39 %, 17 %, 13 %, and 23 % for NASA OMI, QA4ECV OMI, and TROPOMI at finer (0.05° x 0.05°) and coarser (0.15° x 0.15°) spatial resolution, respectively. Campaign-averaged uncertainty values (root mean square error, RMSE) in NASA and QA4ECV OMI HCHO retrievals were ~9.0 x 10 15 molecules cm –2 (∼ 50 %–55 % of mean column abundance), and the higher-spatial-resolution retrievals from TROPOMI resulted in RMSE values ∼30 % lower. Spatially averaging TROPOMI tropospheric-column HCHO, along with NO 2 and FNRs, to resolutions similar to the OMI reduced the uncertainty in these retrievals. Systematic biases in OMI and TROPOMI NO 2 and HCHO retrievals tended to cancel out, resulting in all three satellite products comparing well to observed FNRs. However, while satellite-derived FNRs had minimal campaign-averaged median biases, unresolved errors in the indicator species did not cancel out in FNR calculations, resulting in large RMSE values compared to observations. Uncertainties in HCHO retrievals were determined to drive the unresolved biases in FNR retrievals.

Matthew S. Johnson↗
DOE OSTI2018

Proceedings of the 2018 PV Reliability Workshop, 27 February - 1 March 2018, Lakewood, Colorado

NREL hosts an annual Photovoltaic Reliability Workshop (PVRW) so solar technology experts can share information leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology - both critical goals for moving PV technologies deeper into the electricity marketplace. This document collects the presentations and posters from the 2018 PV Reliability Workshop, which was hosted by NREL from Tuesday, February 27, to Thursday, March 1, 2018.

14 SOLAR ENERGY↗
DOE OSTI2019

Multimodality imaging: Bird’s eye view from The European Society of Cardiology Congress 2018 Munich, August 25–29, 2018

At the European Society of Cardiology (ESC) congress of this year 2018, held in Munich from August 25th to 29th, 4594 abstracts were presented. Of those, 423 (10.8%) belonged to an imaging category. Experts in echocardiography (VD), cardiovascular magnetic resonance (CMR) (CBD), nuclear imaging (OG), and cardiac computed tomography (CT) (PMH) have selected the abstracts in their areas of expertise that were of most interest to them and are summarized in this bird’s eye view from this ESC meeting. These abstracts were integrated by one of the Editors of the Journal (JB).

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2023

Energy Frontier Research Centers: Center for the Computational Design of Functional Layered Materials (CCDM) August 1, 2014 - July 31, 2018; Center for Complex Materials from First Principles (CCM) August 1, 2018 - July 31, 2021 (Final Report)

The mission of the DOE Energy Frontier Research Centers CCDM (2014-2018) and CCM (2018-2021) was to theoretically develop, computationally apply, and experimentally validate electronic structure methods for all materials, with a focus on the complex materials, especially layered and two-dimensional materials, strongly-correlated materials, and liquid water. This was achieved by over 200 published journal articles authored by about 17 senior investigators from physics and chemistry and from theory, computation, and experiment, plus their collaborators. In particular, the Centers confirmed the predictive power of the SCAN (strongly constrained and appropriately normed) density functional, which was constructed to satisfy 17 known exact constraints and several appropriate norms. Without being fitted to real bonded systems, and at a modest computational cost, SCAN correctly predicted covalent, ionic, metallic, hydrogen, and van der Waals bonds in many challenging materials. SCAN gave an improved description of defects in semiconductors, surface properties of metals, seven phases of ice, liquid water, liquid and supercooled silicon, subtle structural distortions in ferroelectrics, formation energies and structural predictions for solids, and critical pressures for structural phase transitions. Perhaps most remarkably, SCAN correctly described some strongly-correlated materials that were previously believed to be beyond the reach of density-functional approximations. SCAN is the only density functional that correctly predicts the band gap closing under chemical doping of the cuprate high-temperature superconducting materials. SCAN also predicts a landscape of competing stripe and magnetic phases in the cuprates. For some materials with some codes, SCAN has convergence problems that are greatly reduced by the CCM-developed r 2 SCAN, without loss of accuracy or rigor. SCAN and r 2 SCAN still make some self-interaction error, which is greatly reduced by the CCDM/ CCM-developed local orbital scaling correction (LOSC). These Centers further proved that the fundamental energy gaps of a solid from an orbital energy difference and from total energy differences are the same for a large class of generalized Kohn-Sham (GKS) functionals, including SCAN and standard hybrid functionals, and that symmetry breaking arises when a dynamic density fluctuation drops to zero frequency. The Centers identified new mechanisms for catalysis in layered materials with ions intercalated between the layers, investigated charge density waves both in model systems and in real layered materials, studied changes of band gap with the number of layers, and explored topological ultrathin films, bent nanoribbons, and defects.

08 HYDROGEN↗