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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 937 records · Page 52
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Lead isotopic compositions of airborne particulates collected from snow and from dry deposition in the East River Watershed, Colorado and at the Southern Sierra Critical Zone Observatory, California

The data set consists of lead (Pb) isotopic ratios (206Pb/207Pb and 208Pb/207Pb, as well as 206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb) for particulate samples collected from snow and dry deposition. This was part of a study (O’Day et al. 2020) that was looking at the speciation of phosphorous in splits of these samples to evaluate the flux and bio-availability of phosphorous to the mountain sites in the study. The Pb isotopic data allow sourcing of long-range transported Pb, specifically the fraction of Pb sourced in Asia, and so a comparison of the relative distances of PM sources between the high and low elevation sites. Samples were collected at the East River Watershed, CO (dry deposition collected over Sept.-Oct. 2016, show sampling winter 2017) and at the Southern Sierra Critical Zone Observatory (dry deposition collected over Sept-Nov 2016, July-Sept 2017, June-July 2017). The data includes Pb concentration data, as well as calculated fraction of the Pb sourced in Asia. This data set was published in part in O’Day et al. (2020) Phosphorus Speciation in Atmospherically Deposited Particulate Matter and Implications for Terrestrial Ecosystem Productivity. ES&T, https://dx.doi.org/10.1021/acs.est.9b06150

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

C fluxes from incubations of California upland soil with and without synthetic iron (hydr)oxide associations

There is a growing understanding that interactions with soil mineral phases contribute to the accumulation and retention of otherwise degradable organic matter in soils and sediments. However, the bioavailability of organic compounds in mineral-organic-associations, especially under varying environmental conditions is not well known. To assess the impact of mineral association and warming on the decomposition of an easily respirable organic substrate (glucose), we conducted a series of laboratory incubations at different temperatures with field-collected soils from 10 to 20 cm, 50–60 cm, and 80–90 cm depth at the Blodgett Forest Research Station. We added 13C-labeled glucose either directly to native soil or sorbed to one of two synthetic iron (hydr)oxide phases (goethite and ferrihydrite) that differ in crystallinity and affinity for sorbing glucose. We incubated the soils at 25 deg C. This dataset comprises the added glucose C and the cumulative fluxes over 72 and 1896 hours. We found that: (1) association with the Fe (hydr)oxide minerals reduced the decomposition rate of glucose by > 99.5% relative to rate of decomposition for free glucose in soil; (2) the respiration rate per gram carbon did not differ appreciably with depth, suggesting a similar degree of decomposability for native C across depths and that under the incubation conditions total carbon availability represents the principal limitation on respiration under these conditions as opposed to reduced abundance of decomposers or moisture and oxygen limitations; (3) addition of free glucose enhanced native carbon respiration at all soil depths with the largest effect at 50–60 cm; (4) in general respiration of the organo-mineral complex (glucose and iron-(hydr)oxide) was less temperature sensitive than was respiration of native carbon; (5) the addition of organic free mineral decreased the rate of soil respiration in the intermediate 50–60 cm depth soil. The results emphasize the key role of MOAs in regulating the fluxes of carbon from soils to the atmosphere and in turn the stocks of soil carbon.This dataset lists the glucose additions made to soils with and without added geothite or ferrihidrite and the C respired over the timespan of the incubations.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Influence of root- vs needle-derived litter on soil C and N stabilization in a California coniferous forest from 2001 to 2011

How plant inputs from above- versus below-ground affect long term carbon (C) and nitrogen (N) retention and stabilization in soils is not well known. We present results of a decade-long field study that traced the decomposition of 13C- and 15N-labeled Pinus ponderosa needle and fine root litter placed in O or A soil horizons of a sandy Alfisol under a coniferous forest. We measured the retention of litter-derived C and N in particulate (>2 mm) and bulk soil (<2 mm) fractions, as well as in density-separated free light and three mineral-associated fractions. After 10 years, the influence of slower initial mineralization of root litter compared to needle litter was still evident: almost twice as much root litter (44% of C) was retained than needle litter (22–28% of C). After 10 years, the O horizon retained more litter in coarse particulate matter implying the crucial comminution step was slower than in the A horizon, while the A horizon retained more litter in the finer bulk soil, where it was recovered in organo-mineral associations. Retention in these A horizon mineral-associated fractions was similar for roots and needles. Nearly 5% of the applied litter C (and almost 15% of the applied N) was in organo-mineral associations, which had centennial residence times and potential for long-term stabilization. Vertical movement of litter-derived C was minimal after a decade, but N was significantly more mobile. Overall, the legacy of initial litter quality influences total SOM retention; however, the potential for and mechanisms of long-term SOM stabilization are influenced not by litter type but by soil horizon.This dataset comprises (1) litter recovery for each of 5 timepoints in >2mm, <2mm, and density fractions, (2) density fractionation results for the 10-year timepoint, and (3) vertical movement of applied litter.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Modeled sub-hourly nitrate concentrations in subsurface water across a salt marsh system in Elkhorn Slough, California

Salt marshes are dynamic hydrologic systems where terrestrial groundwater, terrestrial surface water, and seawater mix due to bi-directional flows and pressure gradients. Salt marshes are known to remove excess nitrate from water thereby improving water quality in coastal systems. However, our knowledge of the short-term processes (e.g., intra-tidal) in salt marshes is limited. Further, we lack knowledge about how these short-term dynamics may change as a function of seasonality. To address this knowledge gap, we develope a sampling methodology that allowed us to continuously measure nitrate in subsurface water at three different depths across three marsh elevations at sub-hourly time steps. Here we present a data table with the results of nitrate in porewater across the three salt marsh elevations (information in the data set). We analyzed nitrate with a s::can spectrophotometer. We used the UV-Vis absorbance of the samples to calculate nitrate concentrations using a local calibration library. More information about the methodology can be found in Grande et al (2023). Seasonal and Tidal Variations in Hydrologic Inputs Drive Salt Marsh Porewater Nitrate Dynamics, Hydrological Processes.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Oxygen isotope ratios in zircon and garnet: A record of assimilation and fractional crystallization in the Dinkey Dome peraluminous granite, Sierra Nevada, California

Abstract The 119 Ma Dinkey Dome pluton in the central Sierra Nevada Batholith is a peraluminous granite and contains magmatic garnet and zircon that are complexly zoned with respect to oxygen isotope ratios. Intracrystalline SIMS analysis tests the relative importance of magmatic differentiation processes vs. partial melting of metasedimentary rocks. Whereas δ18O values of bulk zircon concentrates are uniform across the entire pluton (7.7‰ VSMOW), zircon crystals are zoned in δ18O by up to 1.8‰, and when compared to late garnet, show evidence of changing magma chemistry during multiple interactions of the magma with wall rock during crustal transit. The evolution from an early high-δ18O magma [δ18O(WR) = 9.8‰] toward lower values is shown by high-δ18O zircon cores (7.8‰) and lower δ 18O rims (6.8‰). Garnets from the northwest side of the pluton show a final increase in δ18O with rims reaching 8.1‰. In situ REE measurements show zircon is magmatic and grew before garnets. Additionally, δ18O in garnets from the western side of the pluton are consistently higher (avg = 7.3‰) relative to the west (avg = 5.9‰). These δ18O variations in zircon and garnet record different stages of assimilation and fractional crystallization whereby an initially high-δ18O magma partially melted low-δ18O wallrock and was subsequently contaminated near the current level of emplacement by higher δ18O melts. Collectively, the comparison of δ18O zoning in garnet and zircon shows how a peraluminous pluton can be constructed from multiple batches of variably contaminated melts, especially in early stages of arc magmatism where magmas encounter significant heterogeneity of wall-rock assemblages. Collectively, peraluminous magmas in the Sierran arc are limited to small <100 km2 plutons that are intimately associated with metasedimentary wall rocks and often surrounded by later and larger metaluminous tonalite and granodiorite plutons. The general associations suggest that early-stage arc magmas sample crustal heterogeneities in small melt batches, but that with progressive invigoration of the arc, such compositions are more effectively blended with mantle melts in source regions. Thus, peraluminous magmas provide important details of the nascent Sierran arc and pre-batholithic crustal structure.

Geochemistry & Geophysics↗
DOE OSTI2020

Abstract for CRADA among the National Energy Technology Laboratory, National Technology & Engineering Solutions of Sandia, The Regents of the University of California, and Tri-State Generation and Transmission Association, Inc. (AGMT-0855)

The objective of this CRADA is to facilitate cooperation among Tri-State Generation and Transmission Association, Inc. and collaborators of the Institute for the Design of Advanced Energy Systems (IDAES), including the National Energy Technology Laboratory, Sandia National Laboratories, and Lawrence Berkeley National Laboratory. The goal is to develop steady-state and dynamic optimization models of power plants. Tri-State will provide data related to the design and operation of power plants, which will be used to validate the IDAES team’s models and tools. These models will provide insight into potential improvements which could improve heat rate, reduce operations and maintenance costs, and/or improve reliability of the existing fleet of coal plants in the United States.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2020

Wood-to-Fuel for California's Transportation Sector using Autothermal Pyrolysis, March 2020 (Progress Report for FRD-17-002)

In the month of March, we planned to have the Site License Agreement with SPI signed and fully executed, make further progress on the market assessment for the Wood-to-Bio-oil Market Report, and hoped to have the subcontracts in place with Iowa State University and Frontline BioEnergy, LLC. We also hoped to have the updated budget from Iowa State in order to send both updated sub-recipient budget sheets to the CAM for approval.

09 BIOMASS FUELS↗
DOE OSTI2020

Wood-to-Fuel for California's Transportation Sector using Autothermal Pyrolysis (Progress Report for FRD-17-002)

In the month of April, we planned to have the Site License Agreement with SPI signed and fully executed, make further progress on the market assessment for the Wood-to-Bio-oil Market Report, and hoped to have the subcontracts in place with Iowa State University and Frontline BioEnergy, LLC once we have approval from the CAM. We also plan to have the updated budget from Iowa State in order to send both updated sub-recipient budget sheets to the CAM for approval.We continue to make more progress towards getting our subcontracts in place and received the requested adjustments to ISU’s budget sheets. These were sent to the CAM on 4/30/2020. As the COVID-19 situation is country-wide, we anticipate slower responses from our partners due to similar delays in their organizations to what we are experiencing internally. Although their response times will be slower, both ISU and Frontline are continuing to make good progress on their work for the demonstration in Iowa for this summer, which is assisting with keeping us on schedule for the overall effort. We are continuing to work on the required documents for our subcontracts – though neither will be placed before we receive official approval from our CAM – so that once we have approval, we can place them very quickly.

09 BIOMASS FUELS↗
DOE OSTI2020

Wood-to-Fuel for California's Transportation Sector using Autothermal Pyrolysis (Progress Report)

In the month of May, we planned to have the Site License Agreement with SPI signed and fully executed, make further progress on the market assessment for the Wood-to-Bio-oil Market Report, and hoped to have the subcontracts in place with Iowa State University and Frontline BioEnergy, LLC once we ha approval from the CAM. We also planned to have the updated Advanced Reconciliation to the CAM for approval as requested.

09 BIOMASS FUELS↗
DOE OSTI2020

Modeling the Impact of Flexible CHP on the Future Electric Grid In California

Combined heat and power (CHP) systems provide electricity and process heat at more than 4,400 industrial and commercial facilities across the United States. Typically fueled with natural gas, a CHP system combines a prime mover (such as a reciprocating engine) with a generator and heat recovery equipment, allowing operation at very high efficiencies (65–85%). Traditionally, CHP systems have been configured to serve local electrical and thermal loads at the sites where they are deployed. Units are sized to ensure a high capacity factor for the equipment, and the electricity generated tends to be used on site. CHP units in the United States already generate over 12% of the nation’s electricity. However, CHP’s potential benefits could be much greater if power generated could be used beyond the site, because the analysis was performed under the assumption that sites could use all the thermal output. Analysis of a few key sectors confirmed that this assumption is valid (for more information, see Appendix E). Those benefits could include improved grid reliability and resilience, as well as lower-cost options for providing energy and other grid services. The potential benefits also align well with grid modernization objectives, as shown in Combined heat and power (CHP) systems provide electricity and process heat at more than 4,400 industrial and commercial facilities across the United States., and greater electrification of loads, driven by carbon reduction priorities.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2020

Wood-to-Fuel for California's Transportation Sector using Autothermal Pyrolysis (FRD-17-002 Progress Report)

Both our subcontract with ISU and the one with Frontline have been finalized and the requisitions for the initiation of them have been submitted (this places defined amounts of funding available to the subcontracts, for the first allotment of work to be done, for which we already have funds from the CEC). Once the requisitions are approved, the subcontracts will be fully executed. During the month of August, further work on the Market Report was carried out, and will continue, as this is the most adaptable of the LLNL-main tasks to working remotely, so will not have any delays due to the shelter-in-place orders. Organization of our databases and sources on availability, and potential availability of all woody biomass was continued. Tables and figures for the report were begun as well, and the outline was finalized. Additionally, a parametric study for pyrolysis’ different products was done, with a metric of return on capital investment being chosen. Evaluated parameters include feedstock price, CO2 credit price, CO2 transport cost, and minimum fuel selling price, for drop-in fuels.

09 BIOMASS FUELS↗
DOE OSTI2020

Wetland/Aquatic Resources Delineation Sitewide Environmental Impact Statement, Lawrence Livermore National Laboratory Facilities, Alameda and San Joaquin Counties, California

Nomad Ecology, LLC (Nomad) prepared this Wetland/Aquatic Resources Delineation at the request of Lawrence Livermore National Laboratory (LLNL) for their Sitewide Environmental Impact Statement (SWEIS). This Wetland/Aquatic Resource Delineations presents the results for three LLNL locations: LLNL Livermore (Site 200), LLNL Experimental Test Site (Site 300), and the Arroyo Mocho Pumping Station (Arroyo Mocho). Table 1 summarizes each study area and lists the Assessor’s Parcel Numbers (APNs).

54 ENVIRONMENTAL SCIENCES↗