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At least 1,099 records · Page 61
All sourcesNASA NTRSDOE OSTI
NASA NTRS2008

The NASA Energy and Water Cycle Extreme (NEWSE) Integration Project

Skillful predictions of water and energy cycle extremes (flood and drought) are elusive. To better understand the mechanisms responsible for water and energy extremes, and to make decisive progress in predicting these extremes, the collaborative NASA Energy and Water cycle Extremes (NEWSE) Integration Project, is studying these extremes in the U.S. Southern Great Plains (SGP) during 2006-2007, including their relationships with continental and global scale processes, and assessment of their predictability on multiple space and time scales. It is our hypothesis that an integrative analysis of observed extremes which reflects the current understanding of the role of SST and soil moisture variability influences on atmospheric heating and forcing of planetary waves, incorporating recently available global and regional hydro- meteorological datasets (i.e., precipitation, water vapor, clouds, etc.) in conjunction with advances in data assimilation, can lead to new insights into the factors that lead to persistent drought and flooding. We will show initial results of this project, whose goals are to provide an improved definition, attribution and prediction on sub-seasonal to interannual time scales, improved understanding of the mechanisms of decadal drought and its predictability, including the impacts of SST variability and deep soil moisture variability, and improved monitoring/attributions, with transition to applications; a bridging of the gap between hydrological forecasts and stakeholders (utilization of probabilistic forecasts, education, forecast interpretation for different sectors, assessment of uncertainties for different sectors, etc.).

House, P. R.↗
NASA NTRS2010

Spectral Indices to Monitor Nitrogen-Driven Carbon Uptake in Field Corn

Climate change is heavily impacted by changing vegetation cover and productivity with large scale monitoring of vegetation only possible with remote sensing techniques. The goal of this effort was to evaluate existing reflectance (R) spectroscopic methods for determining vegetation parameters related to photosynthetic function and carbon (C) dynamics in plants. Since nitrogen (N) is a key constituent of photosynthetic pigments and C fixing enzymes, biological C sequestration is regulated in part by N availability. Spectral R information was obtained from field corn grown at four N application rates (0, 70, 140, 280 kg N/ha). A hierarchy of spectral observations were obtained: leaf and canopy with a spectral radiometer; aircraft with the AISA sensor; and satellite with EO-1 Hyperion. A number of spectral R indices were calculated from these hyperspectral observations and compared to geo-located biophysical measures of plant growth and physiological condition. Top performing indices included the R derivative index D730/D705 and the normalized difference of R750 vs. R705 (ND705), both of which differentiated three of the four N fertilization rates at multiple observation levels and yielded high correlations to these carbon parameters: light use efficiency (LUE); C:N ratio; and crop grain yield. These results advocate the use of hyperspectral sensors for remotely monitoring carbon cycle dynamics in managed terrestrial ecosystems.

Corp, Lawrence A.↗
NASA NTRSDate not supplied

In-Orbit Selection of Cryocooler Drive Frequencies for XRISM/Resolve

The XRISM/Resolve instrument cooling system uses adiabatic demagnetization refrigerators (ADRs) to cool the detectors to 50 mK and two types of cryocoolers to reduce heat load on the He tank, Joule-Thomson and Stirling cryocoolers. Resolve was designed with tunable cryocooler frequencies so that any mechanical interference and its effect on performance could be minimized. Measurements at different cryocooler drive frequencies were used to quantify the interference and narrow the acceptable range of frequency options. For Resolve the choice of cryocooler drive frequencies dramatically influences the instrument performance. Poor choices have been shown to degrade ADR cooling power and degrade the spectroscopic performance of the instrument. However, good choices have been shown to be free of undesirable features, allowing the instrument to satisfy its performance requirements with significant margin. Thus, the choice of drive frequencies is a critical factor for overall instrument performance. The drive frequencies of the Joule-Thomson cooler operating near 52 Hz, and the Stirling coolers operating near 15 Hz were adjusted in three distinct scan sequences to efficiently narrow the candidate frequency options. The frequency choices were based on stability of the 50 mK control thermometer, changes in the ADR demagnetization rate, and changes in detector noise. Scans across the drive frequency range of each cryocooler were performed multiple times during ground testing. Surprisingly, the results were not repeatable across test campaigns and did not conform to any discernable trend, but they were repeatable when remeasured within a single cool-down cycle. The conclusion was that the good/bad drive frequencies changed during Dewar warmup/cooldown, and possibly after mechanical vibration tests. Therefore, the settings could not be finalized before launch, and scans during instrument commissioning were necessary. This paper describes the cryocooler frequency scan measurements and compares the results during instrument commissioning to those performed during ground tests.

Gary A. Sneiderman↗
NASA NTRSDate not supplied

In-Orbit Selection of Cryocooler Drive Frequencies for XRISM/Resolve

The XRISM/Resolve instrument cooling system uses adiabatic demagnetization refrigerators (ADRs) to cool the detectors to 50 mK and two types of cryocoolers to reduce heat load on the He tank, Joule-Thomson and Stirling cryocoolers. Resolve was designed with tunable cryocooler frequencies so that any mechanical interference and its effect on performance could be minimized. Measurements at different cryocooler drive frequencies were used to quantify the interference and narrow the acceptable range of frequency options. For Resolve the choice of cryocooler drive frequencies dramatically influences the instrument performance. Poor choices have been shown to degrade ADR cooling power and degrade the spectroscopic performance of the instrument. However, good choices have been shown to be free of undesirable features, allowing the instrument to satisfy its performance requirements with significant margin. Thus, the choice of drive frequencies is a critical factor for overall instrument performance. The drive frequencies of the Joule-Thomson cooler operating near 52 Hz, and the Stirling coolers operating near 15 Hz were adjusted in three distinct scan sequences to efficiently narrow the candidate frequency options. The frequency choices were based on stability of the 50 mK control thermometer, changes in the ADR demagnetization rate, and changes in detector noise. Scans across the drive frequency range of each cryocooler were performed multiple times during ground testing. Surprisingly, the results were not repeatable across test campaigns and did not conform to any discernable trend, but they were repeatable when remeasured within a single cool-down cycle. The conclusion was that the good/bad drive frequencies changed during Dewar warmup/cooldown, and possibly after mechanical vibration tests. Therefore, the settings could not be finalized before launch, and scans during instrument commissioning were necessary. This paper describes the cryocooler frequency scan measurements and compares the results during instrument commissioning to those performed during ground tests.

XRISM↗
NASA NTRS2010

Recent Stirling Conversion Technology Developments and Operational Measurements at NASA Glenn Research Center

In support of the Advanced Stirling Radioisotope Generator (ASRG) project and other potential applications, NASA Glenn Research Center (GRC) has initiated convertor technology development efforts in the areas of acoustic emission, electromagnetic field mitigation, thermoacoustic Stirling conversion, and multiple-cylinder alpha arrangements of Stirling machines. The acoustic emission measurement effort was developed as a health monitoring metric for several Stirling convertors undergoing life testing. While accelerometers have been used in the past to monitor dynamic signature, the acoustic sensors were chosen to monitor cycle events, such gas bearing operation. Several electromagnetic interference (EMI) experiments were performed on a pair of Advanced Stirling Convertors (ASC). These tests demonstrated that a simple bucking coil was capable of reducing the alternating current (ac) magnetic field below the ASRG system specification. The thermoacoustic Stirling concept eliminates the displacer typically found in Stirling machines by making use of the pressure oscillations of a traveling acoustic wave. A 100 W-class thermoacoustic Stirling prototype manufactured by Northrop Grumman Space and Technology was received and tested. Another thermoacoustic prototype designed and fabricated by Sunpower, Inc., will be tested in the near future. A four cylinder free piston alpha prototype convertor was received from Sunpower, Inc. and has been tested at GRC. This hardware was used as a proof of concept to validate thermodynamic models and demonstrate stable operation of multiple-cylinder free-piston Stirling conversion. This paper will discuss each of these activities and the results they produced.

Oriti, Salvatore M.↗
DOE OSTI2024

Soil Carbon and Nitrogen Elemental Analysis and Middle Infrared Spectroscopy from the Kougarok Fire Complex, Seward Peninsula, Alaska, 2022

In September and October of 2022, soil samples were collected at the Kougarok Fire Complex near mile marker 86 of the Nome-Taylor Highway on the Seward Peninsula of Alaska. This study site was chosen due to its unique fire history, as the Kougarok Fire Complex has experienced multiple wildfires since 1971. As the Arctic warms, the risk of Arctic tundra fires continues to increase due to warmer summer temperatures and higher frequency of lightning. Burned soil carbon or pyrogenic carbon (PyC) is an important component of C cycling after wildfire, and one that is often overlooked in tundra systems where wildfires are historically rare. To better understand PyC signatures and quantify PyC presence in post-regeneration permafrost regions, soils were sampled from soil pits within the 1971, 2002, and 2019 burn sites, as well as two unburned control sites. At each site, three soil pits were dug to the permafrost table. Soil samples were collected with a trowel from the face of each pit at 10 cm increments down to the permafrost table. Thaw depth, maximum vegetation height, vegetation species composition, and O horizon depth were also collected at each soil pit. An HS2 Hydrosense II Handheld Soil Moisture Sensor was used to collect volumetric soil moisture content at each 10 cm sampling increment. This dataset includes one *.csv of middle infrared spectroscopy measurements of soil samples, one *.csv of field observations, one *.csv of carbon and nitrogen analysis of soil samples, and one *.kml of sampling locations.The Next-Generation Ecosystem Experiments: Arctic (NGEE Arctic) was a 15-year research effort (2012-2027) to reduce uncertainty in Earth System Models by developing a predictive understanding of carbon-rich Arctic ecosystems and feedbacks to climate. NGEE Arctic was supported by the Department of Energy’s Office of Biological and Environmental Research.The NGEE Arctic project had two field research sites: 1) located within the Arctic polygonal tundra coastal region on the Barrow Environmental Observatory (BEO) and the North Slope near Utqiagvik (Barrow), Alaska and 2) multiple areas on the discontinuous permafrost region of the Seward Peninsula north of Nome, Alaska.Through observations, experiments, and synthesis with existing datasets, NGEE Arctic provided an enhanced knowledge base for multi-scale modeling and contributed to improved process representation at global pan-Arctic scales within the Department of Energy’s Earth system Model (the Energy Exascale Earth System Model, or E3SM), and specifically within the E3SM Land Model component (ELM).

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Overview of the MOSAiC expedition—Atmosphere

With the Arctic rapidly changing, the needs to observe, understand, and model the changes are essential. To support these needs, an annual cycle of observations of atmospheric properties, processes, and interactions were made while drifting with the sea ice across the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition from October 2019 to September 2020. An international team designed and implemented the comprehensive program to document and characterize all aspects of the Arctic atmospheric system in unprecedented detail, using a variety of approaches, and across multiple scales. These measurements were coordinated with other observational teams to explore cross-cutting and coupled interactions with the Arctic Ocean, sea ice, and ecosystem through a variety of physical and biogeochemical processes. This overview outlines the breadth and complexity of the atmospheric research program, which was organized into 4 subgroups: atmospheric state, clouds and precipitation, gases and aerosols, and energy budgets. Atmospheric variability over the annual cycle revealed important influences from a persistent large-scale winter circulation pattern, leading to some storms with pressure and winds that were outside the interquartile range of past conditions suggested by long-term reanalysis. Similarly, the MOSAiC location was warmer and wetter in summer than the reanalysis climatology, in part due to its close proximity to the sea ice edge. The comprehensiveness of the observational program for characterizing and analyzing atmospheric phenomena is demonstrated via a winter case study examining air mass transitions and a summer case study examining vertical atmospheric evolution. Overall, the MOSAiC atmospheric program successfully met its objectives and was the most comprehensive atmospheric measurement program to date conducted over the Arctic sea ice. The obtained data will support a broad range of coupled-system scientific research and provide an important foundation for advancing multiscale modeling capabilities in the Arctic.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Quaternary Cu 2 TSiS 4 (T = Fe, Mn) Anodes for Li-Ion Batteries

Developing high-capacity and fast-charging anode materials is critical for achieving high-performance Li-ion batteries (LIBs). Herein, polycrystalline quaternary transition metal silicon sulfides, Cu 2 TSiS 4 (T = Fe, Mn), were synthesized using a solid-state method and investigated as anode materials in LIBs. Cu 2 FeSiS 4 retains a reversible capacity of 670 mAh g –1 at 200 mA g –1 for 400 cycles, while Cu 2 MnSiS 4 suffers from a fast capacity loss in the initial 50 cycles. More importantly, Cu 2 FeSiS 4 can maintain a reversible capacity of 379 mAh g –1 after 700 cycles at a high current density of 2 A g –1 , demonstrating high cyclic stability and fast-charging capacity. To further understand the structure degradation and phase transformation, we investigated the postcycling electrodes using multiple techniques, including the scanning electron microscope with energy-dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy techniques. The results indicated that Cu 2 FeSiS 4 undergoes reversible phase transitions with Li 2 S as a major product component. To further assess the performance for practical applications, Cu 2 FeSiS 4 was coupled with LiFePO 4 to make LiFePO 4 ||Cu 2 FeSiS 4 full cells, which delivered superior electrochemical performance. These results demonstrate great promise for using quaternary transition metal silicon sulfides as anodes to achieve low-cost and sustainable LIBs.

25 ENERGY STORAGE↗
DOE OSTI2025

Self-assembly of wood-based shape memory composites triggered by solar-thermal energy

Transporting and assembling large, complex structures poses significant challenges due to their size, geometry, and cost. Additionally, the installation sites are often inaccessible or hazardous for humans, necessitating self-assembling capabilities in these structures. To mitigate these challenges, we propose using 3D printing materials with shape memory effect (SME) for both transport and construction. This approach involves developing 3D modular components into flat sheets for easier transportation, and then self-assembling into 3D structures on-site using solar energy. To gain a deeper understanding of the factors influencing material memory performance, we have chosen a composite PLA/WF, which is polylactic acid (PLA) with 20 wt% wood flour (WF) for this purpose, leveraging its high tensile modulus at 0.966 GPa, low cost, and sustainability. Printed shapes with this material can maintain a recovery ratio over 90% after 3 cycles. While traditional composites fillers (e.g. glass or carbon fiber) are added to enhance mechanical and thermal properties, the addition of bio-based fillers like WF accomplish similar goals without compromising sustainability. We conducted multiple experiments to demonstrate how environmental conditions (i.e. temperature) maximize the material’s SME. Although still at an early stage, this study provides initial insights into bridging the gap between the small-scale nature of shape memory polymers (SMPs) and their potential for large-scale additive manufacturing, addressing a critical need for efficient and sustainable construction. In the long term, we hope our study contributes to the design vision of utilizing SMPs for transportation, assembly, and deployment of complex structures, providing a new pathway for sustainable construction and transportation of large-scale structures to hard-to-access locations such as disaster-affected areas and remote deserts, etc.

4D printing↗
DOE OSTI2020

Modifying Network Guided Vehicle for Repeatable EcoCAR ACC Energy Testing

The newest iteration of the Department of Energy (DOE) Advanced Vehicle Technology Competitions is the EcoCAR Mobility Challenge. In this paper, ANL and HORIBA MIRA collaborate to propose and pilot a test method that enables controlled, repeatable track-based energy consumption testing of semi-autonomous features. The testing was performed at MIRA’s proving ground facility in Nuneaton, UK, using their Network Guided Vehicle (NGV) connectivity and automation test platform. The NGV served as a repeatable lead vehicle following prescribed drive traces around two different track circuits while the host vehicle under test, a Honda Civic with full speed range Adaptive Cruise Control, followed behind. Over the course of a two day test, multiple iterations of certification and custom EPA drive traces were performed on track, demonstrating the viability of a two vehicle energy test. Results were analyzed to assess NGV lead vehicle performance in following the prescribed cycle using SAE J2951 standard calculations in an effort to quantify how repeatably and accurately the lead vehicle followed the trace. Host vehicle energy consumption was assessed using both vehicle CAN bus monitoring and an on-board fuel flow meter.

ACC↗
DOE OSTI2024

Modeling the Effects of Artificial Drainage on Agriculture-dominated Watersheds using a Fully Distributed Integrated Hydrology Model: Datasets, scripts, model files

This model-data archive supports the research paper that demonstrates the integration of agricultural drainage features—specifically, narrow engineered ditches and tile drains—into a fully distributed, basin-scale integrated surface-subsurface hydrology model (ISSHM), Amanzi-ATS. The model employs innovative computational meshes aligned with agricultural ditches and incorporates the physically based Hooghoudt's drainage equation to simulate tile drainage, offering a novel strategy that enhances the accuracy of hydrological simulations.The archived dataset includes input parameters, model configurations, and select simulation outputs for the Amanzi-ATS model that successfully captured the streamflow patterns in the Portage River Watershed as validated by USGS gauge readings. Jupyter notebook for the preparation of model inputs and post-processing of outputs are also included. The model's predictive performance achieved a normalized Kling-Gupta Efficiency (KGE) of 0.81, surpassing SWAT without the necessity for site-specific calibration.The Amanzi-ATS model presented in this modeL-data archive allows for numerical experiments to explore the shifts in the flow structure under different drainage scenarios. As a tool for advancing the understanding of distributed hydrological responses and nutrient cycling, this archived model provides valuable insights for researchers, modelers, and decision-makers involved in watershed management and environmental modeling.The Watershed Workflow package is implemented in Python3. The Jupyter notebooks can be executed through multiple open-source tools, for example, Anaconda Jupyter Lab, VS Studio Code, etc. Other data files include CSV and HDF5 files, which can be read through Python scripts. The input files for the ATS model, open-source integrated hydrology, and transport model, are in XML format and can be edited in any commonly used text editors.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1995

PC Software graphics tool for conceptual design of space/planetary electrical power systems

This paper describes the Decision Support System (DSS), a personal computer software graphics tool for designing conceptual space and/or planetary electrical power systems. By using the DSS, users can obtain desirable system design and operating parameters, such as system weight, electrical distribution efficiency, and bus power. With this tool, a large-scale specific power system was designed in a matter of days. It is an excellent tool to help designers make tradeoffs between system components, hardware architectures, and operation parameters in the early stages of the design cycle. The DSS is a user-friendly, menu-driven tool with online help and a custom graphical user interface. An example design and results are illustrated for a typical space power system with multiple types of power sources, frequencies, energy storage systems, and loads.

Truong, Long V.↗
NASA NTRS1996

Lunar Base Heat Pump

The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

Walker, D.↗
NASA NTRS2006

Beyond Population and Environment: Household Life Cycle Demography and Land Use Allocation among Small Farm Colonists in the Amazon

Most research featuring demographic factors in environmental change has focused on processes operating at the level of national or global populations. This paper focuses on household-level demographic life cycles among colonists in the Amazon, and evaluates the impacts on land use allocation. The analysis goes beyond prior research by including a broader suite of demographic variables, and by simultaneously assessing their impacts on multiple land uses with different economic and ecological implications. We estimate a system of structural equations that accounts for endogeneity among land uses, and the findings indicate stronger demographic effects than previous work. These findings bear implications for modeling land use, and the place of demography in environmental research.

Perz, Stephen G.↗
NASA NTRS2008

Miniature High-Force, Long-Stroke SMA Linear Actuators

Improved long-stroke shape-memory-alloy (SMA) linear actuators are being developed to exert significantly higher forces and operate at higher activation temperatures than do prior SMA actuators. In these actuators, long linear strokes are achieved through the principle of displacement multiplication, according to which there are multiple stages, each intermediate stage being connected by straight SMA wire segments to the next stage so that relative motions of stages are additive toward the final stage, which is the output stage. Prior SMA actuators typically include polymer housings or shells, steel or aluminum stages, and polymer pads between successive stages of displacement-multiplication assemblies. Typical output forces of prior SMA actuators range from 10 to 20 N, and typical strokes range from 0.5 to 1.5 cm. An important disadvantage of prior SMA wire actuators is relatively low cycle speed, which is related to actuation temperature as follows: The SMA wires in prior SMA actuators are typically made of a durable nickel/titanium alloy that has a shape-memory activation temperature of 80 C. An SMA wire can be heated quickly from below to above its activation temperature to obtain a stroke in one direction, but must then be allowed to cool to somewhat below its activation temperature (typically, less than or equal to 60 C in the case of an activation temperature of 80 C) to obtain a stroke in the opposite direction (return stroke). At typical ambient temperatures, cooling times are of the order of several seconds. Cooling times thus limit cycle speeds. Wires made of SMA alloys having significantly higher activation temperatures [denoted ultra-high-temperature (UHT) SMA alloys] cool to the required lower return-stroke temperatures more rapidly, making it possible to increase cycle speeds. The present development is motivated by a need, in some applications (especially aeronautical and space-flight applications) for SMA actuators that exert higher forces, operate at greater cycle speeds, and have stronger housings that can withstand greater externally applied forces and impacts. The main novel features of the improved SMA actuators are the following: 1) The ends of the wires are anchored in compact crimps made from short steel tubes. Each wire end is inserted in a tube, the tube is flattened between planar jaws to make the tube grip the wire, the tube is compressed to a slight U-cross-section deformation to strengthen the grip, then the crimp is welded onto one of the actuator stages. The pull strength of a typical crimp is about 125 N -- comparable to the strength of the SMA wire and greater than the typical pull strengths of wire-end anchors in prior SMA actuators. Greater pull strength is one of the keys to achievement of higher actuation force; 2) For greater strength and resistance to impacts, housings are milled from aluminum instead of being made from polymers. Each housing is made from two pieces in a clamshell configuration. The pieces are anodized to reduce sliding friction; 3) Stages are made stronger (to bear greater compression loads without excessive flexing) by making them from steel sheets thicker than those used in prior SMA actuators. The stages contain recessed pockets to accommodate the crimps. Recessing the pockets helps to keep overall dimensions as small as possible; and, 4) UHT SMA wires are used to satisfy the higher-speed/higher-temperature requirement.

Cummin, Mark A.↗
NASA NTRS2011

Telemetry and Science Data Software System

The Telemetry and Science Data Software System (TSDSS) was designed to validate the operational health of a spacecraft, ease test verification, assist in debugging system anomalies, and provide trending data and advanced science analysis. In doing so, the system parses, processes, and organizes raw data from the Aquarius instrument both on the ground and while in space. In addition, it provides a user-friendly telemetry viewer, and an instant pushbutton test report generator. Existing ground data systems can parse and provide simple data processing, but have limitations in advanced science analysis and instant report generation. The TSDSS functions as an offline data analysis system during I&T (integration and test) and mission operations phases. After raw data are downloaded from an instrument, TSDSS ingests the data files, parses, converts telemetry to engineering units, and applies advanced algorithms to produce science level 0, 1, and 2 data products. Meanwhile, it automatically schedules upload of the raw data to a remote server and archives all intermediate and final values in a MySQL database in time order. All data saved in the system can be straightforwardly retrieved, exported, and migrated. Using TSDSS s interactive data visualization tool, a user can conveniently choose any combination and mathematical computation of interesting telemetry points from a large range of time periods (life cycle of mission ground data and mission operations testing), and display a graphical and statistical view of the data. With this graphical user interface (GUI), the data queried graphs can be exported and saved in multiple formats. This GUI is especially useful in trending data analysis, debugging anomalies, and advanced data analysis. At the request of the user, mission-specific instrument performance assessment reports can be generated with a simple click of a button on the GUI. From instrument level to observatory level, the TSDSS has been operating supporting functional and performance tests and refining system calibration algorithms and coefficients, in sync with the Aquarius/SAC-D spacecraft. At the time of this reporting, it was prepared and set up to perform anomaly investigation for mission operations preceding the Aquarius/SAC-D spacecraft launch on June 10, 2011.

Bates, Lakesha↗
DOE OSTI2022

Bio-Optimized Technologies to Keep Thermoplastics out of Landfills and the Environment (BOTTLE)

Plastics have revolutionized modern life, but reliance on these fossil-based materials that persist for centuries is causing a pollution crisis and contributing to greenhouse gas (GHG) emissions. To develop new technologies to address this problem, the Bio-Optimized Technologies to keep Thermoplastics out of Landfills and the Environment (BOTTLE) Consortium will deliver selective, scalable technologies to enable cost-effective recycling, upcycling, and increased energy efficiency. BOTTLE is an interdisciplinary team of experts that aim to develop selective, scalable processes to deconstruct and upcycle today's plastics and thermosets, redesign tomorrow's plastics to be recyclable-by-design (RBD) and derived from both bio-based and plastic waste-based feedstocks, work with industrial partners across the value chain to catalyze the circular economy for plastics, and leverage AMO and BETO investments in analysis-guided R&D, integrated process development, chemical and biological catalysis, materials characterization, modeling, and data science. BOTTLE is guided by techno-economic analysis (TEA) and supply chain-based life-cycle assessment (LCA). BOTTLE comprises members from ten partner institutions. Primary outcomes to date include establishment of a full consortium, impactful, benchmarking analyses that will be important for the plastics recycling and upcycling community, and multiple impactful, high-impact publications across the breadth of our research portfolio.

bio-optimized↗
DOE OSTI2025

Response of Subsurface Nitrogen-Cycling Microbial Communities to Environmental Fluctuations (Final Technical Report)

Riparian floodplains are dynamic ecosystems linking terrestrial and riverine systems. These floodplains experience hydrological shifts such as changes in water table height, flooding, and drought and can be ‘hotspots’ of biogeochemical cycling due to shifting sediment moisture (and saturation) and subsurface exchanges of water, nutrients, and other compounds across different sediment layers. Subsurface microbial communities are the primary drivers of biogeochemical processes in floodplains, and thus their structure and function can directly influence both surface and groundwater quality. The microbial nitrogen (N) cycle is particularly important in floodplains as it affects nutrient availability and removal. Two functional guilds of chemoautotrophic (i.e. CO2-fixing) microorganisms are responsible for the first oxidative step of the N cycle, nitrification: ammonia-oxidizing archaea (AOA) and bacteria (AOB) catalyze the oxidation of ammonia to nitrite, while nitrite-oxidizing bacteria (NOB) oxidize nitrite to nitrate. Despite the critical role nitrification plays in N-cycling in both terrestrial and aquatic ecosystems, our understanding of the diversity, ecophysiology, and activity of nitrifying organisms in subsurface floodplain soils/sediments is extremely limited. To help address this critical knowledge gap, the overarching goal of this project was to determine how shifts in key environmental parameters and gradients impact microbial N-cycling communities/processes, with particular emphasis on nitrification, within hydrologically-variable floodplain sediments in the Wind River Basin near Riverton, Wyoming. The three specific objectives of this project were to: (1) to associate in situ environmental drivers of N cycling with distinct functional guilds; (2) determine the guild response to variation in key ecosystem drivers; and (3) develop a dynamic ecosystem model of the microbial N cycle with the Riverton subsurface using community genomic and biogeochemical data collected in the first two objectives. Over the course of this project, we employed both 16S rRNA gene amplicon sequencing and genome-resolved metagenomics to examine the phylogenetic diversity and metabolic potential of subsurface nitrifier communities within 68 samples collected across multiple sites, depths, and time points within the Riverton floodplain, allowing for both spatial and temporal investigations at different scales. This project benefitted tremendously from recent advances in high-throughput sequencing technologies coupled with dramatic improvements in the computational tools and algorithms available for analyzing such large, complex genomic datasets. By pairing these cutting-edge genomic approaches with depth-resolved sampling and detailed geochemical analyses of the Riverton floodplain, we have gained novel insights into the structure and function of subsurface nitrifier communities in relation to both hydrology and biogeochemistry. This project resulted in the most detailed and comprehensive characterization of N-cycling floodplain microbial communities to date and will hopefully inspire and pave the way for future studies using similar approaches in other floodplains. Indeed, such information is critical for understanding subsurface biogeochemical cycling and how elemental stores are altered from perturbations initiated by the water cycle within floodplains. Finally, because of the terrestrial-aquatic nature of the Riverton floodplain, results from this project are also of relevance to disciplines such as soil science, estuarine science, limnology & oceanography, biogeochemistry, geobiology, environmental engineering, as well as genomics and data science.

54 ENVIRONMENTAL SCIENCES↗