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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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Bioengineered algal lipids enriched in structured medium- and long-chain triacylglycerols, linoleate, and sn -2 palmitate for human milk fat substitutes

Human milk fat (HMF) contains triacylglycerol (TAG) as its primary component, providing over 50% of the calories for infant nutrition, along with structural and bioactive lipids that are important for immune and nervous system development. Palmitic acid, comprising 20-25% of the fatty acid complement of HMF, is predominantly esterified to the sn -2 position on the glycerol backbone. This regiospecific positioning facilitates absorption as 2-palmitoyl-monoacylglycerol after hydrolysis of the fatty acids at sn -1 and sn -2 by gut lipases. Other features of HMF include enrichment in structured medium- and long-chain triglycerides (MLCTs), and variation in the ratio of oleic acid to linoleic acid with maternal diet and geography. We have engineered Auxenochlorella, an oleaginous green alga, for biosynthesis of an MLCT- and sn -2 palmitate-enriched HMF substitute for infant formula, matching the regioisomeric composition and proportions of the most abundant fatty acids in HMF.

Lin, Jon Y-T [University of California, Berkeley;]↗
DOE OSTI2025

Minimum GHG emissions and energy consumption of U.S. PET and polyolefin packaging supply chains in a circular economy

There is a wide agreement on the urgency of transforming linear management of plastics towards a circular economy model. However, no clear pathways exist as to required recycling technologies involved and system-wide environmental impacts. This study explores such pathways in the U.S. for the most commonly used packaging plastics through a combination of mechanical and emerging advanced recycling technologies. A system optimization model aimed at minimizing environmental impacts was developed to determine optimal end-of-life (EOL) management and locations of existing and emerging U.S. recycling infrastructures. Our study includes material flows from virgin resin production through semi-manufacturing processes to existing EOL disposal and recycling processes. An optimized circular plastics packaging system achieved greenhouse gas (GHG) emission savings of up to 28% and cumulative energy demand (CED) savings of up to 46%, compared to the linear economy. Moreover, these savings of GHG emissions and CED impacts represent a reduction of 0.16% and 0.49% compared to annual U.S. GHG emissions and energy consumption in 2022, respectively. The optimal recycling rates and systems-level circularity ranged from 78–99% and 57–75%, respectively. Increased energy savings led to increased GHG emissions showing a potential trade-off between GHG emissions and energy. Analysis of 40 scenarios showed the importance of material collection distances, blend limit of mechanically recycled resins, process yields, and mandated recycling rates for achieving a sustainable circular economy of plastics.

09 - BIOMASS FUELS↗
DOE OSTI2026

Time-of-flight inelastic neutron scattering data of the quantum spin-Peierls chain CuGeO3

Inelastic neutron scattering data of co-aligned CuGeO3 single crystals (5.21 g). The data were collected at SEQUOIA time-of-flight spectrometer. The samples were mounted with the (0KL) plane horizontal. Co-alignment was achieved with overall mosaicity of 1 degree. The data were collected at 5 K, 20 K, 50 K, 100 K, and 150 K with incident neutron energies Ei = 24 and 60 meV and the standard high-resolution chopper condition.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Nuclear Fuel Cycle and Supply Chain (NFCSC) Technical Monthly September FY-24

AFC hosted the Light Water Reactor (LWR) Fuels Research Workshop and Electric Power Research Institute (EPRI) Collaborative Research on Advanced Fuel Technologies (CRAFT) Meeting September 9-13, 2024. The Department of Energy's (DOE) Advanced Fuels Campaign (AFC) Accident Tolerant Fuel (ATF) program is pivotal in advancing clean energy through collaborative innovation in fuel technology for light water reactors (LWRs). For over a decade, AFC has engaged a wide array of stakeholders—researchers, industry participants, and regulatory bodies—both within the U.S. and internationally to develop ATF technology. This initiative aims to enhance the safety and economic performance of both Pressurized Water Reactors (PWRs) and LWRs. To foster community relationships and disseminate research, AFC initiated annual LWR Fuel workshops in 2024, supplementing ongoing industry-led CRAFT workshops.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2025

Analysis of Hydrogen Supply Chain Readiness in Selected Indo-Pacific Countries

This report explores the low-carbon hydrogen production and procurement targets of Indo-Pacific Economic Framework for Prosperity (IPEF) countries, highlighting key cost and infrastructure considerations. By 2030, production costs are targeted between US$\$$1.4-4.8/kg-H2, with procurement prices at US$\$$2.3/kg-H2, narrowing further by 2050. Midstream costs, including storage and transportation, are critical to meeting these targets and enabling hydrogen trade. The report discusses challenges such as infrastructure readiness, regulatory frameworks, and the need for improved data reporting. It emphasizes the importance of tax incentives, research investments, and port readiness to support the growth of low-carbon hydrogen markets in the region.

08 HYDROGEN↗
DOE OSTI2025

Supply Chain Energy and Greenhouse Gas Analysis Using the Materials Flows Through Industry (MFI) Tool: Examination of Alternative Technology Scenarios for the U.S. Chemical Sector

Chemical manufacturing is a large and diverse sector of the U.S. economy, with products, fuels, and a wide assortment of materials used daily by both the public and businesses. Currently, several of the largest volume chemicals produced in the United States rely on fossil fuels as a feedstock, energy source, or both. The list of chemicals includes steam cracking products such as ethylene, propylene, benzene, and xylenes as well as products such as ammonia and methanol. The focus for this work is on platform chemicals that are both produced in the largest volume and have a high potential for subsequent processing into more specialized products. In this study, we explore several new pathways that reduce the overall energy consumption and greenhouse gas (GHG) emissions for each product. These pathways include energy efficiency measures applied to existing production methods, the use of bio‐based fuels and/or feedstocks as new production methods, and electrification of high‐energy‐input stages within current production methods. Scenarios for energy demand and GHG reduction were conducted with the National Renewable Energy Laboratory's Materials Flows through Industry tool. Projections of the energy demand and GHG emissions in 2030 and 2050 are included, using grid composition projections from the NREL ReEDS model. The alternative scenarios selected showcase the effect of realistic changes the industry could make, focusing on technologies with a high level of technical readiness.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2024

Correlation of Processing and Structure in an Ethylene‐Glycol Side‐Chain Modified Polythiophene via Combined X‐Ray Scattering and 4D Scanning Transmission Electron Microscopy

The results of a combined grazing incidence wide-angle X-ray scattering (GIWAXS) and 4D scanning transmission microscopy (4D-STEM) analysis of the effects of thermal processing on poly(3[2-(2-methoxyethoxy)ethoxy]-methylthiophene-2,5-diyl) are reported, a conjugated semiconducting polymer used as the active layer in organic electrochemical transistor devices. GIWAXS provides a measure of overall crystallinity in the film, while 4D-STEM produces real-space maps of the morphology and orientation of individual crystallites along with their spatial extent and distribution. The sensitivity of the 4D-STEM detector allows for collection of electron diffraction patterns at each position in an image scan while limiting the imparted electron dose to below the damage threshold. In conclusion, the effects of heat treatment on the distribution and type of crystallites present in the films is determined.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Opportunities for Cerium Valorization in the Rare Earth Supply Chain

Rare earth (RE) elements are co-located in ore deposits and must be treated together during the difficult extraction and separation. Cerium is the majority element in most deposits (> 50 %), and the growing need for Nd, Pr and the heavy lanthanides in permanent magnets and other energy transition technologies results in costly stockpiling of cerium oxide which has low demand. Finding new high-value applications for cerium or its compounds is therefore a sought-after goal to improve the profitability of rare earth mining and processing. Here, this contribution will highlight the use of cerium in high-strength aluminum alloys and the preparation of Ce-based permanent magnets as two emerging technologies for high-value products that have potential to stabilize the fluctuating rare earth market, substitute critical materials, support the nascent domestic rare earth industry and provide technologies for the pending green energy transition.

Energy - Conversion, Materials science↗
DOE OSTI2025

Oxidation of n-alkanes using TS-1 and H 2 O 2 : Effects of chain length and solvents

The selective oxidation of n-C 8 H 18 , n-C 12 H 26 , n-C 16 H 34 , n-C 20 H 42 , and n-C 36 H 74 was studied with a goal of using these as models to provide insight into how to functionalize polyolefins. Reactions were carried out using a TS-1 catalyst and H 2 O 2 in a batch reactor with different cosolvents, including methanol, acetone, acetonitrile, methyl ethyl ketone, and methyl butyl ketone. Rates decreased with increasing alkane size, possibly due to the reduced solubility of larger alkanes into the water-rich phases. Cosolvents that promote the partitioning of alkanes in the aqueous phase increased the rates. 1 H NMR spectroscopy demonstrated that ketones were the primary products, although some alcohols also formed. There was preferential reaction at the 2 position in the alkanes, but reaction at central carbons was also observed. The results of this study suggest strategies for using this catalytic chemistry to functionalize polyolefins.

Alkane oxidation↗
DOE OSTI2025

A chain stretch-based gradient-enhanced model for damage and fracture in elastomers

Similar to quasi-brittle materials, it has been recently shown that elastomers can exhibit a macroscopically diffuse damage zone that accompanies the fracture process. In this study, we introduce a stretch-based gradient-enhanced damage (GED) model that allows the fracture to localize and also captures the development of a physically diffuse damage zone. This capability contrasts with the paradigm of the phase field method for fracture, where a sharp crack is numerically approximated in a diffuse manner. Capturing fracture localization and diffuse damage in our approach is achieved by considering nonlocal effects that encompass network topology, heterogeneity, and imperfections. These considerations motivate the use of a statistical damage function dependent upon the nonlocal deformation state. From this model, fracture toughness is realized as an output. While GED models have been classically utilized for damage modeling of structural engineering materials (e.g., concrete), they face challenges when trying to capture the cascade from damage to fracture, often leading to damage zone broadening (de Borst and Verhoosel, 2016). This deficiency contributed to the popularity of the phase-field method over the GED model for elastomers and other quasi-brittle materials. Other groups have proceeded with damage-based GED formulations that prove identical to the phase-field method (Lorentz et al., 2012), but these inherit the aforementioned limitations. To address this issue in a thermodynamically consistent framework, we implement two modeling features (a nonlocal driving force bound and a simple relaxation function) specifically designed to capture the evolution of a physically meaningful damage field and the simultaneous localization of fracture, thereby overcoming a longstanding obstacle in the development of these nonlocal strain- or stretch-based approaches. Here, we discuss several numerical examples to understand the features of the approach at the limit of incompressibility, and compare them to the phase-field method as a benchmark for the macroscopic response and fracture energy predictions.

Elastomers↗
DOE OSTI2024

Advancing equitable value chains for the global hydrogen economy

Hydrogen is a rapidly growing focus for countries seeking to develop green industries, but there are many questions about how the nascent global hydrogen economy will develop, and what this implies for equitable sharing of benefits and burdens between nations. In this perspective we summarize emerging trends in national hydrogen strategies and develop recommendations for researchers and policymakers to center equity in hydrogen development. This will require integrating innovation and development perspectives on international technology transfer, developing more detailed representation of hydrogen trade in systems models, building equity considerations into national and international planning processes, and establishing robust technology transfer efforts. In conclusion, policymakers will also need to grapple with the difficulties of verifying life cycle emissions of hydrogen if hydrogen trade emerges as a significant trend, potentially requiring new methods of emissions accounting and trade reforms that prioritize international equity.

08 HYDROGEN↗
DOE OSTI2026

The need to consider regional supply chains and water usage in H 2 –steel transition

The iron and steel industry is one of the largest contributors to U.S. and global greenhouse gas emissions. Hydrogen can act as a promising reducing agent and clean energy carrier to decarbonize this sector, and has received significant attention in terms of process modelling, techno-economic analysis, and life cycle assessment in recent years. Policy incentives, hydrogen storage and transportation, and water stress levels are key factors that require significantly more consideration in order to realize hydrogen’s potential to decarbonize this industry. This review demonstrates the need for a systematic understanding and critical assessment of these areas, and their profound impacts on the decarbonization of the iron and steel sector. Furthermore, hydrogen and water supply face competition from other hard-to-decarbonize sectors, which should be considered on national and regional levels. Lastly, future research should also consider the impact of other environmental factors and hydrogen leak when deploying hydrogen at scale for industrial decarbonization.

Green steel↗