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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 595 records · Page 33
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

The spore coat is essential for Bacillus subtilis spore resistance to pulsed light, and pulsed light treatment eliminates some spore coat proteins

Microbial surface contamination of equipment or of food contact material is a recurring problem in the food industry. Spore-forming bacteria are far more resistant to a wide variety of treatments than their vegetative forms. Understanding the mechanisms underlying decontamination processes is needed to improve surface decontamination strategies against endospores potentially at the source of foodborne diseases or food-spoilage. Pulsed light (PL) with xenon lamps delivers high-energy short-time pulses of light with wavelengths in the range 200 nm-1100 nm and a high UV-C fraction. Bacillus subtilis spores were exposed to either PL or to continuous UV-C. Gel electrophoresis and western blotting revealed elimination of various proteins of the spore coat, an essential outer structure that protects spores from a wide variety of environmental conditions and inactivation treatments. Proteomic analysis confirmed the elimination of some spore coat proteins after PL treatment. Transmission electron microscopy of PL treated spores revealed a gap between the lamellar inner spore coat and the outer spore coat. Overall, spores of mutant strains with defects in genes coding for spore coat proteins were more sensitive to PL than to continuous UV-C. This study demonstrates that radiations delivered by PL contribute to specific damage to the spore coat, and overall to spore inactivation. Keywords Decontamination, UV, proteins, proteomics, microscopy Journal Pre-proof

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

The development of natural gas and hydrogen pipeline capital cost estimating equations

Natural gas pipeline cost data collected by the Oil and Gas Journal (O&GJ) for interstate pipelines constructed from 1980 through 2017 were used to develop capital cost estimating equations that are a function of pipeline diameter, length, and U.S. region. Equations were developed for material, labor, miscellaneous, and right-of-way costs, the four cost components in the O&GJ data, for six different regions of the United States (U.S.). Each equation is a function of pipeline diameter and length. Adjustment mechanisms were then developed for converting the natural gas pipeline equations into equations for estimating the costs of hydrogen pipelines. These adjustments were based in part on an analysis completed by the National Institute for Standards and Technology (NIST). Here the results of this work were used to update cost models in the Hydrogen Delivery Scenario Analysis Model (HDSAM), developed by Argonne National Laboratory for the U.S. Department of Energy’s Hydrogen Program. Our analysis shows a wide range of pipeline cost across different U.S. regions, especially with respect to labor and right-of-way costs. The developed cost formulas for hydrogen pipelines are both important and timely as hydrogen is being considered as a zero-carbon energy carrier with the potential to decarbonize all energy sectors, and the cost of hydrogen transportation is essential for techno-economic analysis of its potential use in these sectors.

03 NATURAL GAS↗
DOE OSTI2021

A Prospective Randomized Trial of the Influence of Music on Anxiety in Patients Starting Radiation Therapy for Cancer

One of the most downloaded articles in 2017 from the International Journal of Radiation Oncology, Biology, and Physics was a study suggesting that music therapy during radiation therapy (RT) simulation substantially reduces anxiety. To further evaluate the potential of music's clinical efficacy in the context of radiation therapy, we conducted a randomized trial evaluating the influence of genre-based music chosen by the study participant on anxiety during the first RT treatment session with a method that is applicable to routine clinical practice.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2022

A comparison of carbon impurities in pre- and post-melt uranium Part 2: Scanning/Transmission electron microscopy analysis

We report the speciation and morphology of U carbide inclusions in pre- and post-melt U metal have been explored using high-resolution analytical electron microscopy (AEM). This report presents Part 2 of our study, in which aberration (C s ) corrected transmission and scanning transmission electron microscopy (S)TEM was used to elementally and crystallographically characterize C-containing impurities and defect features in U samples for comparison with results obtained by scanning electron microscopy (SEM) in Part 1, previously published by this journal. Elemental mapping and unit cell matching of inclusions by (S)TEM are consistent with phases observed by SEM, and new dislocations can be observed associating with some inclusion morphologies and not others.

36 MATERIALS SCIENCE↗
DOE OSTI2021

From multivariate to functional data analysis: Fundamentals, recent developments, and emerging areas

Functional data analysis (FDA), which is a branch of statistics on modeling infinite dimensional random vectors resided in functional spaces, has become a major research area for Journal of Multivariate Analysis. We review some fundamental concepts of FDA, their origins and connections from multivariate analysis, and some of its recent developments, including multi-level functional data analysis, high-dimensional functional regression, and dependent functional data analysis. Here, we also discuss the impact of these new methodology developments on genetics, plant science, wearable device data analysis, image data analysis, and business analytics. Two real data examples are provided to motivate our discussions.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2023

System modeling for grid-interactive efficient building applications

Despite the abundance of research applications of system modeling in grid-interactive efficient buildings (GEBs), the transfer of those applications to real-world practices is still in its early stages. This is partially due to the lack of a summary on how system modeling should be established for a given application of GEBs. Here, we fill this gap by providing an extensive survey of the literature on system modeling for different GEBs that have been produced in the past decade. This survey involves over 300 relevant journal articles from the building community, the power system community, and the society of control. Specifically, we first identified key requirements of system modeling for GEBs based on various types of applications discussed in those publications. We then summarized the system modeling applications from those publications, in terms of their assumptions, modeling approach, and simulation. After that, we analyzed different assumptions made for various applications, the extent to which those modeling approaches satisfied the key requirements, and how those approaches can be scaled up for large-scale applications, which are quite common in GEBs. In addition, we gave insights on how to use system modeling for different applications in GEBs. At the end, we provided recommended directions for future studies to fully unleash the potentials of system modeling to support GEBs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Universal Workflow Language and Software Enable Geometric Learning and FAIR Scientific Protocol Reporting

Written language and conventional data structures for representing scientific procedures suffer from low process detail, often fail to accurately represent protocols, and lack universality. New strategies for the handling of experimental data are needed to provide viable process information for both humans and machines. In this work, we present the universal workflow language (UWL) and interface (UWLi). UWL is a findable, accessible, interoperable, and reusable (FAIR)-compatible, graph-based data architecture that can capture arbitrary scientific procedures through workflow representation, and UWLi is an accompanying software package for building, manipulating, and interpreting UWL entries. The UWL format was found to be highly effective in identifying deficiencies in the reported process details of high-impact, peer-reviewed scientific journals, and in simulated scenarios, the graph format was shown to be more effective than conventional methods in predictively modeling the outcome of diverse scientific protocols. Implementation of UWL could enable more accurate scientific communication and more impactful process datasets.

14 SOLAR ENERGY↗
DOE OSTI2024

Editorial for Multiscale & Multifield Coupling in Geomechanics

We are delighted to serve as guest editors for this special issue in the Journal of Rock Mechanics and Geotechnical Engineering. The purpose of this special issue is dedicated to gathering the latest research work on Multiscale & Multifield Coupling in Geomechanics, where we delve into the intricate interplay of various fields and scales that govern the behavior of geomaterials. In total, 30 manuscripts from USA, China, UK, Germany, Canada, India and United Arab Emirates are selected to be included in this issue.

58 GEOSCIENCES↗
DOE OSTI2021

Amphiphile conformation impacts aggregate morphology and solution structure across multiple lengthscales

Although the self-assembly of amphiphiles is well-studied in aqueous solutions, much less is understood about the fundamental driving forces and structure property relationships in non-polar media. In recent work [Journal of Physical Chemistry B, 2020, 124, 10822.] the authors have studied a series of malonomide-based amphiphiles that are relevant to liquid-liquid extraction. That work demonstrated that aggregation is largely driven by local dipole-dipole interactions between molecules. Here, we build upon this observation to develop a more detailed understanding of how the balance of dipole-dipole interactions (controlled by conformation) and molecular architecture influences the morphology of the aggregates across lengthscales. Using constrained molecular dynamics about key degrees of freedom, we demonstrate that the conformation of N,N-dimethyl,N,N-dioctylhexylethoxy malonamide (DMDOHEMA) and N,N-dimethyl,N,N-dibutyltetradecyl malonamide (DMDBTDMA) has a significant impact upon self-association - where appropriate conformational sampling is essential. To quantify the aggregate morphology, several graph theoretic and persistent homology based properties are determined. The former examines the patterns of intermolecular interactions within clusters, while the latter examines the 3-dimensional spatial distribution. Based upon these analyses, we find that the morphology of aggregates, particularly at higher malonamide concentration, depends on a balance of dipole alignment and alkyl tail sterics. Dipole alignment encourages linear patterns of the intermolecular interactions within aggregates, while the alkyl tail steric interactions between the malonamide result in noticeably less linear aggregates for DMDOHEMA than DMDBTDMA. This is reflected in the spatial distribution, where more holes or voids exist between extractants within the DMDOHEMA that distribute within the solution in more of a "swiss cheese" arrangement as opposed to the more filamentous distribution of DMBDTDMA. This study links conformation and molecular structure to the morphology of amphiphile assemblies, and serves as a basis for ongoing study of multicomponent amphiphile solutions with polar and other solutes, and how these impact aggregation phenomena.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Comparison of Results from Recent NNSA and CEA Measurements of the 239 Pu(n, f) Prompt Fission Neutron Spectrum

The National Nuclear Security Administration (NNSA)/DP French Alternative Energies and Atomic Energy Commission (CEA)/DAM agreement on cooperation on fundamental science is a U.S.-French collaborative effort to combine intellectual and experimental resources and further the relevant nuclear science. Recently, both the NNSA and CEA experimental teams performed high-statistics measurements of the 239 Pu(n, f) prompt fission neutron spectrum (PFNS) at the Los Alamos Neutron Science Center, both of which were recently published in the journal Physical Review C. These separate measurements used the same experimental area and a common neutron detector array, but differ in many aspects, including background assessments, data acquisition systems and philosophies, fission detectors, and PFNS extraction techniques. Hence, some aspects of the experimental methods and associated uncertainties are highly correlated while others are independent. The results from both measurements broke new ground for PFNS measurements given their higher accuracy and more detailed study of corrections necessary for the measured quantity compared to existing literature measurements, and both will significantly impact PFNS nuclear data evaluations for the foreseeable future. Here, the focus of this work is to document a comparison of the results from these distinct measurements in terms of the acquired data, the PFNS results, and the measured average PFNS energies. While systematic differences between the PFNS results are present on the 1–3% level, the acquired data relative to each respective measurement at low incident neutron energies are in remarkable agreement, as are the conclusions regarding the magnitude and position of features in the PFNS relating to second-chance fission, third-chance fission, and pre-equilibrium neutron emission.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2026

Beta-delayed gamma spectra compilation and analysis following the thermal-neutron induced fission of 235 U, 239,241 Pu

The integral gamma and electron spectra emitted by fission products, also known as delayed gamma and electron spectra, were measured at Oak Ridge National Laboratory in the 1970s for the thermal-neutron induced fission of 235 U and 239,241 Pu. Scintillator detectors were used to measure these spectra, data used later on to obtain decay heat values - that is, the spectra mean values per unit time as function of time - work that was published in the Nuclear Science and Technology journal; the spectral data, however, was only published in laboratory reports. Here, in this work, we analyze the gamma spectra data using modern methods and nuclear databases to reveal the signature of individual fission products as well as to gauge the performance of the ENDF/B-VIII.0 decay data sub-library, concluding about possible future enhancements in predictive capabilities.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

Erratum to “Systematic Trends of $0^+_2$, $1^-_1$, $3^-_1$ and $2^+_1$ Excited States in Even-Even Nuclei” [Nucl. Phys. A 1027 (2022) 122511]

In our publication [Nucl. Phys. A 1027 (2022) 122511, https://doi.org/10.1016/j.nuclphysa.2022.122511] we have detected typographical errors in Table 4 [List of $2^+_1$ States in Even-Even Nuclei]. The misprints of decimals with one or more trailing zeros are not central to our findings, however, they may confuse the journal readers and require corrections. In addition, we have included recent results for the $0^+_2$ and $2^+_1$ first excited states that are not available in the ENSDF library as of April, 2021 or B(E2) tables.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2025

Measurement of the top quark mass with the ATLAS detector using $t\bar{t}$ events with a high transverse momentum top quark

Journal article.The mass of the top quark is measured using top-quark-top-antiquark pair events with high transverse momentum top quarks. The dataset, collected with the ATLAS detector in proton–proton collisions at $\sqrt{s}$ = 13 TeV delivered by the Large Hadron Collider, corresponds to an integrated luminosity of 140 fb −1 . The analysis targets events in the lepton-plus-jets decay channel, with an electron or muon from a semi-leptonically decaying top quark and a hadronically decaying top quark that is sufficiently energetic to be reconstructed as a single large-radius jet. The mean of the invariant mass of the reconstructed large-radius jet provides the sensitivity to the top quark mass and is simultaneously fitted with two additional observables to reduce the impact of the systematic uncertainties. The top quark mass is measured to be m t = 172.95 ± 0.53 GeV, which is the most precise ATLAS measurement from a single channel.

Aad, G. (ORCID:0000000266654934)↗
DOE OSTI2024

Waste management strategies for military-generated waste in the United States

Sustainable and energy efficient municipal solid waste (MSW) management is vital for the health and performance of deployed soldiers, as they play an important role in the safety and dignity of a country. As the United States targets net-zero carbon-free emission goals, research and development are essential to surpassing current practices for management of MSW at military installations, both at home and abroad. To achieve this, it is important to act upon and implement the policies and instructions set by government agencies such as the Environmental Protection Agency (EPA), the Department of Energy (DOE), and the Department of Defense (DoD). Understanding the composition of waste and disposal methods that are in use at military installations is a crucial step to success. Here, the authors show this through analyzed data from trusted sources, such as government agencies, reports, magazines, journals, and other publications on MSW management techniques. By defining these challenges, possible solutions can be better understood for improved management of MSW at military installations in the United States. Finally, an integrated approach with deployable units capable of waste-to-energy technology using waste reduction, diversion, and recycling strategies shows to be an effective pathway for MSW conversion into energy and other useful products.

09 BIOMASS FUELS↗
DOE OSTI2024

Review of data-driven models for quantifying load shed by non-residential buildings in the United States

Shifting and shedding power demand in buildings can be cost-effective techniques for grids to function reliably and for end users to earn compensation. Grid operators reimburse customers in proportion to the quantity of load shed. Simple data-driven methods are used to quantify this shed, which is the difference between a measured load during the event and modeled "baseline" that would have occurred in absence of the event. These methods have evolved over the years and in many cases have been integrated with building physics, to make them a hybrid between physics based and empirical models. However, there is no comprehensive analysis that provides guidance to building operators, grid operators and researchers in selecting appropriate models based on their specific needs and available data. Here, this work aims to fill this gap by critically assessing the performance of baseline models put forward from the year 2000 through 2023. The literature reviewed includes reports generated by grid operators, reports from national laboratories and academic journal articles. The work outlines modeling features like the inputs, training period, estimation method, adjustments to fine tune the predictions and metrics to evaluate the performance. A comprehensive list of 50 models has been provided. For each model, the study explores the applicability of the model to weather sensitive buildings, variability in the building profile, timing of the event, and whether the building reduces energy consumption before an event. The work identifies the situations in which a particular model works and draws lessons based on evidence of performance. Finally, recommendations to aid in model selection are given.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2021

Greenhouse production contributes to pesticide occurrences in Swedish streams

Greenhouse and other covered cultivation systems have increased globally over the past several decades, leading to considerably improved product quality and productivity per land area unit. However, there is a paucity in information regarding the environmental impacts of covered production systems, especially regarding pesticides entering the surrounding environment. Aiming to address this knowledge gap, we collected grab samples downstream of greenhouses from seven Swedish streams every 14 days during a 12 month period. In three of the streams, samples were also taken upstream of the greenhouses and in four of the streams time-integrated samples were collected by TIMFIE samplers in the period between grab sampling occasions. The samples were analyzed for 28 substances (27 that were permitted for use in greenhouse production systems in Sweden and one degradation product to a permitted substance). Pesticide use journals were collected from the greenhouse producers for the 12 month period. The results were examined for indications of greenhouse contributions to detection frequencies, maximum and average concentrations, and potential ecotoxicicity in several ways: (1) comparing locations downstream of greenhouses with registered use of a substance with those without registered use, (2) comparing results from this study with those from the Swedish environmental monitoring program of pesticides in surface water from catchments with no greenhouses from the same period and region, (3) comparing concentration trends with registered pesticide application times in the greenhouses, and (4) comparing up- and downstream concentrations. The results strongly suggest that greenhouse applications do contribute to pesticide occurrences, maximum and median concentrations for most of the pesticides included in this study, and to potential toxicity to aquatic organisms for several of them, most notably imidacloprid, acetamiprid, carbendazim, and pirimicarb.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Evaluation of strategies to narrow the product chain-length distribution of microbially synthesized free fatty acids

The dominant strategy for tailoring the chain-length distribution of free fatty acids (FFA) synthesized by heterologous hosts is expression of a selective acyl-acyl carrier protein (ACP) thioesterase. However, few of these enzymes can generate a precise (greater than 90% of a desired chain-length) product distribution when expressed in a microbial or plant host. The presence of alternative chain-lengths can complicate purification in situations where blends of fatty acids are not desired. We report the assessment of several strategies for improving the dodecanoyl-ACP thioesterase from the California bay laurel to exhibit more selective production of medium-chain free fatty acids to near exclusivity. We demonstrated that matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF MS) was an effective library screening technique for identification of thioesterase variants with favorable shifts in Journal Pre-proof chain-length specificity. This strategy proved to be a more effective screening technique than several rational approaches discussed herein. With this data, we isolated four thioesterase variants which exhibited a more selective FFA distribution over wildtype when expressed in the fatty acid accumulating E. coli strain, RL08. We then combined mutations from the MALDI isolates to generate BTE-MMD19, a thioesterase variant capable of producing free fatty acids consisting of 90% of C12 products. Of the four mutations which conferred a specificity shift, we noted that three affected the shape of the binding pocket, while one occurred on the positively charged acyl carrier protein landing pad. Lastly, we fused the maltose binding protein (MBP) from E. coli to the N – terminus of BTE-MMD19 to improve enzyme solubility and achieve a titer of 1.9 g per L of twelve-carbon fatty acids in a shake flask.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

Recent Advances in Plasma Catalysis

Plasma catalysis is the integration of plasmas and catalysts to achieve reactant conversions and product selectivities that are inaccessible with plasmas or catalysts alone. While chemical transformations via plasma and catalysis are individually well-developed and optimized in many cases, efficient and effective plasma catalysis coupling remains primitive. Molecular understanding of plasma catalysis is further challenged by the complicated natures of plasma and catalysis separately. In this Virtual Issue, we collect 35 examples highlighting recent advances in plasma catalysis that were published in ACS journals from 2019 to 2021. Here, we categorized these 35 into six classes, ranging from fundamental plasma/surface characterizations to applied research on chemical transformations and catalyst synthesis, as presented in Figure 1. We hope this collection is helpful especially to those new to this emerging area.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗