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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 1,099 records · Page 61
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Use of Digital Real-Time Simulation and Optimization to Identify Maximum Real Power Injection on the Banshee Distribution Network: Preprint

This study investigates the hosting capacity of the Banshee Distribution Network by optimizing the real power injection at carefully selected Distributed Energy Resource (DER) locations. The analysis is conducted within the framework of power system operational constraints, including bus voltage ranges, thermal line ratings, and transformer loading limits. A Python-based Genetic Algorithm (GA), implemented using the PyGAD library, is employed to iteratively identify the optimal power injection configuration that maximizes network utilization while preserving system reliability. The methodology integrates a real-time simulation environment using the Real-Time Digital Simulator (RTDS), allowing high-fidelity evaluation of power flow and voltage behavior under each proposed injection scenario. By coupling the optimization algorithm with real-time simulation feedback, this approach ensures that both static and dynamic constraints are enforced during the evaluation process. The GA leverages evolutionary operators such as selection, crossover, and mutation to navigate the nonlinear search space efficiently. The results of the study delineate the feasible hosting capacity at three targeted buses, reflecting maximum real power levels that can be injected without causing voltage violations, transformer overloading, or line congestion. These findings provide a decision- support tool for distribution planners and utilities aiming to integrate higher penetrations of DERs in existing infrastructure. Additionally, the work lays the foundation for extending such optimization techniques to multi-objective formulations, including economic dispatch and reactive power coordination, in future studies.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2021

Unique Building Identifier (UBID): Public Sector Implementation Guide

Buildings generate data throughout their lifecycle – about ownership & taxation, usage, zoning, code compliance, energy use, and retrofits. State and local governments collect this data after it flows through growing networks of people and systems. But collecting data is only half the battle; what’s really needed is information – the actionable insights that lead to successful policy outcomes.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
NASA NTRS1996

A Space Data System Interface for Self-Identifying Devices

Improved technologies and declining budgets for space exploration have space agencies around the world examining new approaches to building and flying spacecraft. This paper descibes development efforts aimed at a standard message specification for space system devices.

self identifying devices self configuring devices ↗
DOE OSTI2017

Potential for Small Unmanned Aircraft Systems Applications for Identifying Groundwater-Surface Water Exchange in a Meandering River Reach: sUAS in Groundwater-Surface Water Study

The exchange of groundwater and surface water (GW-SW), including dissolved constituents and energy, represents a critical yet challenging characterization problem for hydrogeologists and stream ecologists. Here we describe the use of a suite of high spatial resolution remote sensing techniques, collected using a small unmanned aircraft system (sUAS), to provide novel and complementary data to analyze GW-SW exchange. sUAS provided centimeter-scale resolution topography and water surface elevations, which are often drivers of exchange along the river corridor. Additionally, sUAS-based vegetation imagery, vegetation-top elevation, and normalized difference vegetation index mapping indicated GW-SW exchange patterns that are difficult to characterize from the land surface and may not be resolved from coarser satellite-based imagery. We combined these data with estimates of sediment hydraulic conductivity to provide a direct estimate of GW “shortcutting” through meander necks, which was corroborated by temperature data at the riverbed interface.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

The Challenge of Identifying Controls on Cloud Properties and Precipitation Onset for Cumulus Congestus Sampled During MC3E

Here, the controls on precipitation onset and the transition from shallow cumulus to congestus are explored using a suite of 16 large–eddy simulations based on the 25 May 2011 event from the Midlatitude Continental Convective Clouds Experiment (MC3E). The thermodynamic variables in the model are relaxed at various timescales to observationally constrained temperature and moisture profiles in order to better reproduce the observed behavior of precipitation onset and total precipitation. Three of the simulations stand out as best matching the precipitation observations and also perform well for independent comparisons of cloud fraction, precipitation area fraction, and evolution of cloud top occurrence. All three simulations exhibit a destabilization over time, which leads to a transition to deeper clouds, but the evolution of traditional stability metrics by themselves is not able to explain differences in the simulations. Conditionally sampled cloud properties (in particular, mean cloud buoyancy), however, do elicit differences among the simulations. The inability of environmental profiles alone to discern subtle differences among the simulations and the usefulness of conditionally sampled model quantities argue for hybrid observational/modeling approaches. These combined approaches enable a more complete physical understanding of cloud systems by combining observational sampling of time–varying three–dimensional meteorological quantities and cloud properties, along with detailed representation of cloud microphysical and dynamical processes from numerical models.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Identifying and Eliminating Emissive Sub-bandgap States in Thin Films of PbS Nanocrystals

Chemical oxidation of under-charged Pb atoms reduces the density of trap states by a factor of 40 in films of colloidal PbS quantum dots for devices. These emissive sub-bandgap states are a byproduct of several standard ligand-exchange procedures. Finally, X-ray photoelectron spectro­scopy measurements and density function theory simulations demonstrate that they are associated with under-charged Pb.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Identifying Dense NiSe 2 /CoSe 2 Heterointerfaces Coupled with Surface High-Valence Bimetallic Sites for Synergistically Enhanced Oxygen Electrocatalysis

Constructing heterostructures with abundant interfaces is essential for integrating the multiple functionalities in single entities. Herein, the synthesis of NiSe 2 /CoSe 2 heterostructures with different interfacial densities via an innovative strategy of successive ion injection is reported. The resulting hybrid electrocatalyst with dense heterointerfaces exhibits superior electrocatalytic properties in an alkaline electrolyte, superior to other benchmarks and precious metal catalysts. Advanced synchrotron techniques, post structural characterizations, and density functional theory (DFT) simulations reveal that the introduction of atomic-level interfaces can lower the oxidation overpotential of bimetallic Ni and Co active sites (whereas Ni$^{2+}$ can be more easily activated than Co$^{2+}$) and induce the electronic interaction between the core selenides and surface in situ generated oxides/hydroxides, which play a critical role in synergistically reducing energetic barriers and accelerating reaction kinetics for catalyzing the oxygen evolution. Hence, the heterointerface structure facilitates the catalytic performance enhancement via increasing the intrinsic reactivity of metallic atoms and enhancing the synergistic effect between the inner selenides and surface oxidation species. This work not only complements the understanding on the origins of the activity of electrocatalysts based on metal selenides, but also sheds light on further surface and interfacial engineering of advanced hybrid materials.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Identifying Catalytic Active Sites of Trimolybdenum Phosphide (Mo 3 P) for Electrochemical Hydrogen Evolution

Solid-state electrocatalysis plays a crucial role in the development of renewable energy to reshape current and future energy needs. However, finding an inexpensive and highly active catalyst to replace precious metals remains a big challenge for this technology. Here, tri-molybdenum phosphide (Mo 3 P) is found as a promising nonprecious metal and earth-abundant candidate with outstanding catalytic properties that can be used for electrocatalytic processes. The catalytic performance of Mo3P nanoparticles is tested in the hydrogen evolution reaction (HER). The results indicate an onset potential of as low as 21 mV, H 2 formation rate, and exchange current density of 214.7 µmol s -1 g -1 cat (at only 100 mV overpotential) and 279.07 µA cm -2 , respectively, which are among the closest values yet observed to platinum. Combined atomic-scale characterizations and computational studies confirm that high density of molybdenum (Mo) active sites at the surface with superior intrinsic electronic properties are mainly responsible for the remarkable HER performance. The density functional theory calculation results also confirm that the exceptional performance of Mo 3 P is due to neutral Gibbs free energy (ΔG H* ) of the hydrogen (H) adsorption at above 1/2 monolayer (ML) coverage of the (110) surface, exceeding the performance of existing non-noble metal catalysts for HER.

Active sites↗
DOE OSTI2024

Identifying and Amplifying the Spontaneously Formed Photo‐Charge Contribution in Opaque and Semitransparent Organic Photovoltaics

Abstract Spontaneous photo‐charge (SP) generation within the non‐fullerene (NFA) bulk helps avoid exciton (EX) related loss as compared to the traditional heterojunction route in organic solar cells (OSCs). Unfortunately, the promising SP utilization attracts little attention at this time due to the lack of knowledge on its specific contribution to the photovoltaic performance and rational optimization in high‐efficiency devices. To fill the gap, the NFAs’ SP characteristics are related with their photocurrent loss and power conversion efficiency (PCE) in state‐of‐the‐art materials. Though higher SP population is good for efficient EX utilization, it simultaneously acts as an additional photo‐charge recombination channel. The former can be further enhanced by increasing the NFAs’ crystallinity with preferred lamellar growth, and the latter can be suppressed via electric doping. With the aid of the two‐step optimization strategy, the total photocurrent loss is reduced from 14.4% to 4.8%, accompanying with PCE increment from 16.9% to 18.5%. The SP utilization strategy is finally applied in the semitransparent OSCs (ST‐OSCs), due to its less heterojunction area sensitive photo‐charge generation characteristic. A light utilization efficiency (LUE) is then increased from 3.21% to 3.77%. The findings highlight the pursue of efficient SP utilization as a new design philosophy in future OSCs’ progresses.

Chemistry↗
DOE OSTI2015

Identifying Different Types of Catalysts for CO 2 Reduction by Ethane through Dry Reforming and Oxidative Dehydrogenation

Abstract The recent shale gas boom combined with the requirement to reduce atmospheric CO 2 have created an opportunity for using both raw materials (shale gas and CO 2 ) in a single process. Shale gas is primarily made up of methane, but ethane comprises about 10 % and reserves are underutilized. Two routes have been investigated by combining ethane decomposition with CO 2 reduction to produce products of higher value. The first reaction is ethane dry reforming which produces synthesis gas (CO+H 2 ). The second route is oxidative dehydrogenation which produces ethylene using CO 2 as a soft oxidant. The results of this study indicate that the Pt/CeO 2 catalyst shows promise for the production of synthesis gas, while Mo 2 C‐based materials preserve the CC bond of ethane to produce ethylene. These findings are supported by density functional theory (DFT) calculations and X‐ray absorption near‐edge spectroscopy (XANES) characterization of the catalysts under in situ reaction conditions.

Porosoff, Marc D.↗
DOE OSTI2016

Identifying Optimal Zeolitic Sorbents for Sweetening of Highly Sour Natural Gas

Abstract Raw natural gas is a complex mixture comprising methane, ethane, other hydrocarbons, hydrogen sulfide, carbon dioxide, nitrogen, and water. For sour gas fields, selective and energy‐efficient removal of H 2 S is one of the crucial challenges facing the natural‐gas industry. Separation using nanoporous materials, such as zeolites, can be an alternative to energy‐intensive amine‐based absorption processes. Herein, the adsorption of binary H 2 S/CH 4 and H 2 S/C 2 H 6 mixtures in the all‐silica forms of 386 zeolitic frameworks is investigated using Monte Carlo simulations. Adsorption of a five‐component mixture is utilized to evaluate the performance of the 16 most promising materials under close‐to‐real conditions. It is found that depending on the fractions of CH 4 , C 2 H 6 , and CO 2 , different sorbents allow for optimal H 2 S removal and hydrocarbon recovery.

Shah, Mansi S.↗
DOE OSTI2018

Identifying the Structural Evolution of the Sodium Ion Battery Na 2 FePO 4 F Cathode

Abstract Na 2 FePO 4 F is a promising cathode material for Na‐ion batteries owing to its relatively high discharge voltage and excellent cycling performance. Now, the long‐ and short‐range structural evolution of Na 2 FePO 4 F during cycling is studied by in situ high‐energy X‐ray diffraction (XRD), ex situ solid‐state nuclear magnetic resonance (NMR), and first‐principles DFT calculations. DFT calculations suggest that the intermediate phase, Na 1.5 FePO 4 F, adopts the space group of P 2 1 / c , which is a subgroup ( P 2 1 / b 11, No. 14) of Pbcn (No. 60), the space group of the starting phase, Na 2 FePO 4 F, and this space group provides a good fit to the experimental XRD and NMR results. The two crystallographically unique Na sites in the structure of Na 2 FePO 4 F behave differently during cycling, where the Na ions on the Na2 site are electrochemically active while those on the Na1 site are inert. This study determines the structural evolution and the electrochemical reaction mechanisms of Na 2 FePO 4 F in a Na‐ion battery.

Li, Qi↗
DOE OSTI2015

Identifying different types of catalysts for CO 2 reduction by ethane through dry reforming and oxidative dehydrogenation

In this study, the recent shale gas boom combined with the requirement to reduce atmospheric CO 2 have created an opportunity for using both raw materials (shale gas and CO 2 ) in a single process. Shale gas is primarily made up of methane, but ethane comprises about 10 % and reserves are underutilized. Two routes have been investigated by combining ethane decomposition with CO 2 reduction to produce products of higher value. The first reaction is ethane dry reforming which produces synthesis gas (CO+H 2 ). The second route is oxidative dehydrogenation which produces ethylene using CO 2 as a soft oxidant. The results of this study indicate that the Pt/CeO 2 catalyst shows promise for the production of synthesis gas, while Mo 2 C-based materials preserve the C—C bond of ethane to produce ethylene. These findings are supported by density functional theory (DFT) calculations and X-ray absorption near-edge spectroscopy (XANES) characterization of the catalysts under in situ reaction conditions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Identifying Optimal Zeolitic Sorbents for Sweetening of Highly Sour Natural Gas

Abstract Raw natural gas is a complex mixture comprising methane, ethane, other hydrocarbons, hydrogen sulfide, carbon dioxide, nitrogen, and water. For sour gas fields, selective and energy‐efficient removal of H 2 S is one of the crucial challenges facing the natural‐gas industry. Separation using nanoporous materials, such as zeolites, can be an alternative to energy‐intensive amine‐based absorption processes. Herein, the adsorption of binary H 2 S/CH 4 and H 2 S/C 2 H 6 mixtures in the all‐silica forms of 386 zeolitic frameworks is investigated using Monte Carlo simulations. Adsorption of a five‐component mixture is utilized to evaluate the performance of the 16 most promising materials under close‐to‐real conditions. It is found that depending on the fractions of CH 4 , C 2 H 6 , and CO 2 , different sorbents allow for optimal H 2 S removal and hydrocarbon recovery.

Shah, Mansi S.↗
DOE OSTI2018

Identifying the Structural Evolution of the Sodium Ion Battery Na 2 FePO 4 F Cathode

Abstract Na 2 FePO 4 F is a promising cathode material for Na‐ion batteries owing to its relatively high discharge voltage and excellent cycling performance. Now, the long‐ and short‐range structural evolution of Na 2 FePO 4 F during cycling is studied by in situ high‐energy X‐ray diffraction (XRD), ex situ solid‐state nuclear magnetic resonance (NMR), and first‐principles DFT calculations. DFT calculations suggest that the intermediate phase, Na 1.5 FePO 4 F, adopts the space group of P 2 1 / c , which is a subgroup ( P 2 1 / b 11, No. 14) of Pbcn (No. 60), the space group of the starting phase, Na 2 FePO 4 F, and this space group provides a good fit to the experimental XRD and NMR results. The two crystallographically unique Na sites in the structure of Na 2 FePO 4 F behave differently during cycling, where the Na ions on the Na2 site are electrochemically active while those on the Na1 site are inert. This study determines the structural evolution and the electrochemical reaction mechanisms of Na 2 FePO 4 F in a Na‐ion battery.

Li, Qi↗