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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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DOE OSTI2022

Industrial Assessment Center – integration of education and practice. Final progress report

The goal of the DOE’s Industrial Assessment Center (IAC) program is twofold: first, to help US manufacturing competitiveness by providing assessments and recommendations for small and medium-sized enterprises (SMEs) on energy efficiency, productivity, sustainability and competitiveness – including measuring the impacts of these recommendations on reducing greenhouse gas emissions; and second, to address a growing shortage of engineering professionals with applied energy and manufacturing-related skills by training a diverse cross-section of engineering students through hands-on involvement in these assessments. IUPUI has an IAC, which was established in 2011, in the Department of Mechanical and Energy Engineering, Purdue School of Engineering and Technology, IUPUI. The IAC has won the awards twice. We have built the center that has the expertise and infrastructure for quality energy assessments to manufactures and commercial building owners and aligned our current research and teaching activities to the DOE’ training mission with programs to train the next generation of industrial energy efficiency experts, with theory and hands-on experience in conducting energy assessment for small and median manufacturing enterprises. We have made recommendations that have the potential to save about $20M annually. We also initiated research projects to meet DOE priorities, specifically in the areas of smart manufacturing and cybersecurity. On the energy assessment side, the Center has provided energy assessments to 144 qualified companies, primarily located in Indiana. On the training side, the center has trained students in various programs, such as the department’s Bachelor of Science (BS) programs in Mechanical Engineering (ME) and BS in Energy Engineering (EEN), both are ABET accredited engineering programs, as well as a graduate level Energy Management and Assessment certificate program. At the present, the center has trained 95 students, 43 or them received the DOE issued certificates. Research projects were developed within the center to advance energy efficiency related technologies, which provided excellent opportunities for our trainees. The center has also been building a professional network with utilities, Manufacturing Extension Partnership (MEP), government agencies, and manufacturing companies, to increase our client base and promote collaborations. The center received the 2019 Center of Excellence of the Year Award and three students received the “Outstanding Achievement in Energy Engineering by an IAC Student” awards in the past five years.

42 ENGINEERING↗
DOE OSTI2025

The Effect of Metal Promoters in an Mo-Supported HZSM-5 Catalyst for Microwave-Assisted Methane Dehydroaromatization to Aromatics

Microwave (MW)-assisted methane dehydroaromatization (MDHA) using an Mo-supported HZSM-5 catalyst (Mo/HZ5) can convert methane into value-added aromatic products in modular microwave reactor systems, enabling producers to generate revenue from an otherwise wasted resource. Modifying the local environments of active Mo species with metal promoters potentially regulates the reaction/deactivation pathways and improves the heating properties of the Mo/HZ5 under microwaves. Herein, metal promoters (M), including monovalent K+ and bivalent Co2+ and Ni2+, were incorporated to form M-Mo/HZ5 and their MDHA performance was investigated.

metal promoters↗
DOE OSTI2022

A Catalog of Candidate Double and Lensed Quasars from Gaia and WISE Data

Making use of strong correlations between closely separated multiple or double sources and photometric and astrometric metadata in Gaia Early Data Release 3 (EDR3), we generate a catalog of candidate double- and multiply imaged lensed quasars and active galactic nuclei (AGNs), comprising 3140 systems. It includes two partially overlapping parts: a sample of distant (redshifts mostly greater than 1) sources with perturbed data; and systems that have been resolved into separate components by Gaia at separations less than 2''. For the first part, which is roughly one-third of the published catalog, we synthesized 0.617 million redshifts using multiple machine-learning prediction and classification methods, using independent photometric and astrometric data from Gaia EDR3 and the Wide-field Infrared Survey Explorer, with accurate spectroscopic redshifts from the Sloan Digital Sky Survey (SDSS) as a training set. Using these synthetic redshifts, we estimate a 4.9% rate of interlopers with spectroscopic redshifts below 1 in this part of the catalog. Unresolved candidate double and dual AGNs and quasars are selected as sources with a marginally high BP/RP excess factor (phot_bp_rp_excess_factor), which is sensitive to source extent, limiting our search to high-redshift quasars. For the second part of the catalog, additional filters on measured parallax and near-neighbor statistics are applied to diminish the propagation of the remaining stellar contaminants. The estimated rate of the positives (double or multiple sources) is 98%, and the estimated rate of dual (physically related) quasars is greater than 54%. A few dozen serendipitously found objects of interest are discussed in more detail, including known and new lensed images, planetary nebulae, young IR stars of peculiar morphology, and quasars with catastrophic redshift errors in SDSS.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2022

Uncertainty-refined image segmentation under domain shift

A method for digital image segmentation is provided. The method comprises training a neural network for image segmentation with a labeled training dataset from a first domain, wherein a subset of nodes in the neural net are dropped out during training. The neural network receives image data from a second, different domain. A vector of N values that sum to 1 is calculated for each image element, wherein each value represents an image segmentation class. A label is assigned to each image element according to the class with the highest value in the vector. Multiple inferences are performed with active dropout layers for each image element, and an uncertainty value is generated for each image element. The label of any image element with an uncertainty value above a predefined threshold is replaced with a new label corresponding to the class with the next highest value.

Martinez, Carianne↗
DOE OSTI2022

How Can Construction Process Simulation Modeling Aid the Integration of Lean Principles in the Factory-Built Housing Industry?

New and existing factories that produce and deliver factory-built housing can benefit from construction process simulation modeling to explore the integration of Lean principles in their operations. Construction process simulation modeling provides digital or virtual recreations of the real-world factory environments to visualize, quantify, analyze, and optimize their underlying behavior, including factory productivity, material flow, labor dynamics, bottlenecks, and work scope. One of the key benefits of process simulation modeling is the ability to create and compare "what-if" scenarios, including integrating Lean principles such as reducing waste (for example, transportation, waiting), line balancing, and just-in-time concepts. In general, three process simulation methods are widely used: discrete event simulation (DES), agentbased modeling (ABM), and system dynamics (SD). Myriad process simulation software also is available, but depending on the industry, complexity of the system, and purposes of the simulation, some software might be more appropriate. Similar to how computer-aided design (CAD) software such as AutoCAD and Rhinoceros enable building design of modular or factory-built housing, process simulation modeling software such as jStrobe, ProModel, and AnyLogic can enable factory design of new and existing factories to deliver modular affordable housing at scale, as opposed to traditional site-built construction. Software with DES capabilities can help generate a process model that is a logical representation of resources and activities in a factory. Software with CAD-DES integration can leverage product-process data integration to help spatially visualize a DES model of the factory in the CAD environment. Software with multimethod simulation capabilities, widely used in the manufacturing industry, brings together DES, ABM, and SD in a single platform that allows visualization, quantification, analyses, and optimization at varying data fidelities. Near-real-time data from an existing factory can be directly plugged into multimethod simulation software so that the construction process simulation model is a near-accurate representation of the real-world factory conditions. This report provides insights into the use of simulation as an aid to integrate Lean concepts in factories, including guidelines for selecting the appropriate process simulation modeling method and software. These insights have been developed as part of ongoing process simulation modeling research, development, and demonstration projects at the U.S. Department of Housing and Urban Development, the U.S. Department of Energy, and the National Renewable Energy Laboratory focused on how process simulation models can enable better integration of resilience, energy efficiency, and low-carbon design strategies.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2024

Uncertainty-refined image segmentation under domain shift

Digital image segmentation is provided. The method comprises training a neural network for image segmentation with a labeled training dataset from a first domain, wherein a subset of nodes in the neural net are dropped out during training. The neural network receives image data from a second, different domain. A vector of N values that sum to 1 is calculated for each image element, wherein each value represents an image segmentation class. A label is assigned to each image element according to the class with the highest value in the vector. Multiple inferences are performed with active dropout layers for each image element, and an uncertainty value is generated for each image element. Uncertainty is resolved according to expected characteristics. The label of any image element with an uncertainty above a threshold is replaced with a new label corresponding to a segmentation class based on domain knowledge.

Martinez, Carianne↗
DOE OSTI2022

Wintertime Brine Discharge at the Surface of a Cold Polar Glacier and the Unexpected Absence of Associated Seismicity

A subglacial groundwater system beneath Taylor Glacier, Antarctica, discharges hypersaline, iron-rich brine episodically at the glacier surface to create Blood Falls. However, the triggering mechanism for these brine release events is not yet understood. Identifying which fracture processes are observed seismically can help us better characterize the hydrological system at Taylor Glacier, and more generally, provide us with a broader understanding of englacial hydrologic activity in cold glaciers. We document wintertime brine discharge using time-lapse photography. Subfreezing air temperatures during the brine discharge indicate that surface melt-induced hydrofracture is an unlikely trigger for brine release. Further, we analyze local seismic data to test a hypothesis that fracturing generates elevated surface wave energy preceding and/or coinciding with brine release events. Our results show no discernible elevated Rayleigh wave activity prior to or during Blood Falls brine release. Instead, we find a pattern of seismic events dominated by a seasonal signal, with more Rayleigh events occurring in the summer than the winter from the Blood Falls source area. We calculate that the volumetric opening of cracks that would generate Rayleigh waves at our detection limits are of similar size to myriad cracks in glacier ice, lake ice, and frozen sediment in the terminus area. We therefore propose that any fracturing coincident with brine release activity likely consists of a series of smaller opening events that are masked by other seismicity in the local environment.

58 GEOSCIENCES↗
DOE OSTI2024

Redox active plant phenolic, acetosyringone, for electrogenetic signaling

Abstract Redox is a unique, programmable modality capable of bridging communication between biology and electronics. Previous studies have shown that the E. coli redox-responsive OxyRS regulon can be re-wired to accept electrochemically generated hydrogen peroxide (H 2 O 2 ) as an inducer of gene expression. Here we report that the redox-active phenolic plant signaling molecule acetosyringone (AS) can also induce gene expression from the OxyRS regulon. AS must be oxidized, however, as the reduced state present under normal conditions cannot induce gene expression. Thus, AS serves as a “pro-signaling molecule” that can be activated by its oxidation—in our case by application of oxidizing potential to an electrode. We show that the OxyRS regulon is not induced electrochemically if the imposed electrode potential is in the mid-physiological range. Electronically sliding the applied potential to either oxidative or reductive extremes induces this regulon but through different mechanisms: reduction of O 2 to form H 2 O 2 or oxidation of AS. Fundamentally, this work reinforces the emerging concept that redox signaling depends more on molecular activities than molecular structure. From an applications perspective, the creation of an electronically programmed “pro-signal” dramatically expands the toolbox for electronic control of biological responses in microbes, including in complex environments, cell-based materials, and biomanufacturing.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2021

Hosting Capacity Improvement Method Using MV–MV Solid-State-Transformer

As a large number of distributed generations are connected to the distribution system, research on the hosting capacity is actively being conducted. In particular, various methods, such as smart inverter functionality, co-located energy storage systems (ESS), and the use of on-load tap changers (OLTC), have been proposed to improve the hosting capacity. In this paper, a method to improve the hosting capacity by utilizing a solid-state transformer (SST) and its unique control capability is proposed. Lastly, the proposed method is verified in the distribution system of the Republic of Korea using the OpenDSS program.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2025

Improved field assessments of chemicals and explosives using high-resolution gamma-ray spectroscopy with a tagged neutron interrogation system

A fi eld-portable tagged neutron interrogation system is being developed for detection of explosives and chemical warfare agents by prompt gamma-ray neutron activation analysis. The system combines an associated particle imaging deuterium-tritium neutron generator with a high-purity germanium gamma-ray detector. Fine spatial resolution neutron and alpha detectors enable precise mapping of characteristic gamma-ray emission distributions onto high-clarity neutron radiographic images. A narrow coincidence gate associated with each tagged neutron ensures a large signal-to-background ratio, thus signifi cantly improving sensitivity to the chemical compositions of the items being assessed. Recent experimental results recorded from test objects involving mock explosives and other chemicals are presented.

46 - INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AN↗
DOE OSTI2023

The 2.4 Å structure of Zymomonas mobilis pyruvate kinase: Implications for stability and regulation

Human liver pyruvate kinase (hlPYK) catalyzes the final step in glycolysis, the formation of pyruvate (PYR) and ATP from phosphoenolpyruvate (PEP) and ADP. Fructose 1,6-bisphosphate (FBP), a pathway intermediate of glycolysis, serves as an allosteric activator of hlPYK. Zymomonas mobilis pyruvate kinase (ZmPYK) performs the final step of the Entner-Doudoroff pathway, which is similar to glycolysis in that energy is harvested from glucose and pyruvate is generated. The Entner-Doudoroff pathway does not have FBP as a pathway intermediate, and ZmPYK is not allosterically activated. In this work, we solved the 2.4 Å X-ray crystallographic structure of ZmPYK. The protein is dimeric in solution as determined by gel filtration chromatography, but crystallizes as a tetramer. The buried surface area of the ZmPYK tetramerization interface is significantly smaller than that of hlPYK, and yet tetramerization using the standard interfaces from higher organisms provides an accessible low energy crystallization pathway. Interestingly, the ZmPYK structure showed a phosphate ion in the analogous location to the 6-phosphate binding site of FBP in hlPYK. Circular Dichroism (CD) was used to measure melting temperatures of hlPYK and ZmPYK in the absence and presence of substrates and effectors. The only significant difference was an additional phase of small amplitude for the ZmPYK melting curves. We conclude that the phosphate ion plays neither a structural or allosteric role in ZmPYK under the conditions tested. In conclusion, we hypothesize that ZmPYK does not have sufficient protein stability for activity to be tuned by allosteric effectors as described for rheostat positions in the allosteric homologues.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Polariton enhanced free charge carrier generation in donor–acceptor cavity systems by a second-hybridization mechanism

Cavity quantum electrodynamics has been studied as a potential approach to modify free charge carrier generation in donor–acceptor heterojunctions because of the delocalization and controllable energy level properties of hybridized light–matter states known as polaritons. However, in many experimental systems, cavity coupling decreases charge separation. In this work, we theoretically study the quantum dynamics of a coherent and dissipative donor–acceptor cavity system, to investigate the dynamical mechanism and further discover the conditions under which polaritons may enhance free charge carrier generation. We use open quantum system methods based on single-pulse pumping to find that polaritons have the potential to connect excitonic states and charge separated states, further enhancing free charge generation on an ultrafast timescale of several hundred femtoseconds. The mechanism involves polaritons with optimal energy levels that allow the exciton to overcome the high Coulomb barrier induced by electron–hole attraction. Moreover, we propose that a second-hybridization between a polariton state and dark states with similar energy enables the formation of the hybrid charge separated states that are optically active. These two mechanisms lead to a maximum of 50% enhancement of free charge carrier generation on a short timescale. However, our simulation reveals that on the longer timescale of picoseconds, internal conversion and cavity loss dominate and suppress free charge carrier generation, reproducing the experimental results. Thus, our work shows that polaritons can affect the charge separation mechanism and promote free charge carrier generation efficiency, but predominantly on a short timescale after photoexcitation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Stable Co-valorization of Carbon Dioxide and Methane via Dynamic Reconstruction of a Metal Oxide Solid Solution Catalyst

Dry reforming of methane (DRM) is a process that converts two greenhouse gases (methane and carbon dioxide) into syngas, a mixture of H 2 and CO, that can lead to a variety of value-added chemicals. Owing to its endothermic nature, high reaction temperatures up to 800 °C are typically required and the grand challenge lies in developing robust catalysts without sintering and coking-induced deactivation during the long-term on-stream operation. Towards this aim, herein, a robust complex oxide-supported NiCu alloy catalyst was generated in situ during DRM. By leveraging the configurational stability of a solid oxide solution precursor, tightly anchored NiCu bimetallic nanoparticles were in situ exsoluted and acted as the active sites in DRM. The as-afforded catalyst exhibited stable performance for DRM due to the ability to repel coke off the surface as the reaction proceeds. Kinetic experiments along with top surface characterization detail the reconstruction behavior of the solid oxide solution under DRM reaction conditions. In conclusion, the fundamental insights from this work provide guidance on generating resistant and flexible catalysts via in situ active sites formation from easily synthesized metal oxide solid solutions.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2021

A plant host, Nicotiana benthamiana, enables the production and study of fungal lignin-degrading enzymes

Abstract Lignin has significant potential as an abundant and renewable source for commodity chemicals yet remains vastly underutilized. Efforts towards engineering a biochemical route to the valorization of lignin are currently limited by the lack of a suitable heterologous host for the production of lignin-degrading enzymes. Here, we show that expression of fungal genes in Nicotiana benthamiana enables production of members from seven major classes of enzymes associated with lignin degradation (23 of 35 tested) in soluble form for direct use in lignin activity assays. We combinatorially characterized a subset of these enzymes in the context of model lignin dimer oxidation, revealing that fine-tuned coupling of peroxide-generators to peroxidases results in more extensive C-C bond cleavage compared to direct addition of peroxide. Comparison of peroxidase isoform activity revealed that the extent of C-C bond cleavage depends on peroxidase identity, suggesting that peroxidases are individually specialized in the context of lignin oxidation. We anticipate the use of N. benthamiana as a platform to rapidly produce a diverse array of fungal lignin-degrading enzymes will facilitate a better understanding of their concerted role in nature and unlock their potential for lignin valorization, including within the plant host itself.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2026

High fidelity actuator line data from 9 turbine wind farm simulations using ExaWind

This data was generated with the ExaWind code suite (https://github.com/Exawind) to investigate the performance of different Active Wake Mixing turbine control in a wind farm situated in a stable atmospheric boundary layer. All cases correspond to a 3x3 wind farm in a 10km x 10km domain using a total mesh size that varied between 1.6 X 10^9 to 1.85 X 10^9 grid cells. The simulations were run across 1800-2000 GPUs on Frontier. The case description and data generation process is fully documented in Yalla, G. R., Brown, K., Cheung, L., Houck, D., deVelder, N., and Balaji, J. (2025). "Estimating annual energy production of wake mixing control strategies including comparisons to wake steering." Wind Energy Sciences (https://doi.org/10.5194/wes-2025-250).

17 WIND ENERGY↗
DOE OSTI2021

Dependency of active pressure and equation of state on stiffness of wall

Autonomous motion and motility are hallmarks of active matter. Active agents, such as biological cells and synthetic colloidal particles, consume internal energy or extract energy from the environment to generate self-propulsion and locomotion. These systems are persistently out of equilibrium due to continuous energy consumption. It is known that pressure is not always a state function for generic active matter. Torque interaction between active constituents and confinement renders the pressure of the system a boundary-dependent property. The mechanical pressure of anisotropic active particles depends on their microscopic interactions with a solid wall. Using self-propelled dumbbells confined by solid walls as a model system, we perform numerical simulations to explore how variations in the wall stiffness influence the mechanical pressure of dry active matter. In contrast to previous findings, we find that mechanical pressure can be independent of the interaction of anisotropic active particles with walls, even in the presence of intrinsic torque interaction. Particularly, the dependency of pressure on the wall stiffness vanishes when the stiffness is above a critical level. In such a limit, the dynamics of dumbbells near the walls are randomized due to the large torque experienced by the dumbbells, leading to the recovery of pressure as a state variable of density.

42 ENGINEERING↗
DOE OSTI2020

Site-dependent reactivity of MoS2 nanoparticles in hydrodesulfurization of thiophene

The catalytically active site for the removal of S from organosulfur compounds in catalytic hydrodesulfurization has been attributed to a generic site at an S-vacancy on the edge of MoS2 particles. However, steric constraints in adsorption and variations in S-coordination means that not all S-vacancy sites should be considered equally active. Here, we use a combination of atom-resolved scanning probe microscopy and density functional theory to reveal how the generation of S-vacancies within MoS2 nanoparticles and the subsequent adsorption of thiophene (C4H4S) depends strongly on the location on the edge of MoS2. Thiophene adsorbs directly at open corner vacancy sites, however, we find that its adsorption at S-vacancy sites away from the MoS2 particle corners leads to an activated and concerted displacement of neighboring edge S. This mechanism allows the reactant to self-generate a double CUS site that reduces steric effects in more constrained sites along the edge.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2023

A bioinspired cobalt catalyst based on a tripodal imidazole/pyridine platform capable of water reduction and oxidation

The prototypical drug carrier [Co II (L 1 )Cl]PF 6 (1), where L 1 is a tripodal amine bound to pyridine and methyl-imidazoles, had its electrocatalytic water splitting activity studied under different pH conditions. This species contains a high-spin 3d 7 Co II metal center, and is capable of generating both H 2 from water reduction and O 2 from water oxidation. Turnover numbers reach 390 after 3 h for water reduction. Initial water oxidation activity is molecular, with TONs of 71 at pH 7 and 103 at pH 11.5. The results reveal that species 1 can undergo several redox transformations, including reduction to the 3d 8 Co I species that precedes a LS 3d 6 hydride for water reduction, as well as nominal Co IV $=$O and Co III -OOH species required for water oxidation. Finally, post-catalytic analyses confirm the molecular nature of reduction and support initial molecular activity for oxidation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗