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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 55 records · Page 3

3D-RGB

An early attempt at using 3D point clouds to scan plants grown in the APPL facility.

3D RGB

3_Drought_Experiment_1

This is an early experiment in the APPL facility at ORNL looking at the effect of drought on various Populus genotypes. Nisqually-1, WV-94, BESC-394, BESC-198, BESC-24, BESC-375

APPL

Early_Commisioning_Data

This is very early commissioning data (2019) from the newly established APPL facility at ORNL. Instruments, and technologies are in active development at this stage.

APPL

PSI_Testing

Testing data for PSI Instrumentation from 2019 - 2022

appl

Probing the Critical Element Chemistry of Coal-Combustion Fly Ash: Examination of Zircon and Associated Minerals from a Beneficiated Kentucky Fly Ash

Along with the principal rare earth (REE) minerals such as monazite, xenotime, and bastnasite, Y-and REE-bearing zircon and associated minerals survive the combustion process and are found in coal-combustion fly ash. Beneficiated fly ash from a power plant burning an eastern-Kentucky-sourced coal blend was found to have zircon (ZrSiO4), baddeleyite (ZrO2), fergusonite (YNbO4), yttriaite (Y2O3), and xenotime (YPO4). Previous studies of the same fly had also identified monazite with a broad REE suite. Scanning electron microscopy–electron dispersive spectroscopy (EDS) and transmission electron microscopy (TEM)–EDS as well as other TEM-based techniques revealed a variety of zircon associations, including heavy-REE suites with Y, Nb, and Hf. Hafnium is a common accessory element in zircons and the Y and Nb may be present as fergusonite (YNbO4) intermixed with zircon.

Berti, Debora (ORCID:0000000311237794)

Production of Radioactive 22 Na in Core-collapse Supernovae: The Ne-E(L) Component in Presolar Grains and Its Possible Consequences on Supernova Observations

Presolar graphite grains carry the isotopic signatures of their parent stars. A significant fraction of presolar graphites show isotopic abundance anomalies relative to solar for elements such as O, Si, Mg, and Ca, which are compatible with nucleosynthesis in core-collapse supernovae (CCSNe). Therefore, they must have condensed from CCSN ejecta before the formation of the Sun. Their most puzzling abundance signature is the 22 Ne-enriched component Ne-E(L), interpreted as the effect of the radioactive decay of 22 Na (T 1/2 = 2.6 yr). Previous works have shown that if H is ingested into the He shell and not fully destroyed before the explosion, the CCSN shock in the He-shell material produces large amounts of 22 Na. Here we focus on such CCSN models, showing a radioactive 26 Al production compatible with grain measurements, and analyze the conditions of 22Na nucleosynthesis. In these models, 22 Na is mostly made in the He shell, with a total ejected mass varying between 2.6 × 10 −3 M ⊙ and 1.9 × 10 −6 M ⊙ . We show that such 22 Na may already impact the CCSN light curve 500 days after the explosion, and at later stages it can be the main source powering the CCSN light curve for up to a few years before 44 Ti decay becomes dominant. Based on the CCSN yields above, the 1274.53 keV γ-ray flux due to 22 Na decay could be observable for years after the first CCSN light is detected, depending on the distance. This makes CCSNe possible sites to detect a 22 Na γ-ray signature consistently with the Ne-E(L) component found in presolar graphites. Finally, we discuss the potential contribution from 22 Na decay to the Galactic positron annihilation rate.

79 ASTRONOMY AND ASTROPHYSICS

Telomere-to-telomere assemblies of chromosome 10 reveal complex adaptive variation of 3-ketoacyl-CoA-synthases in Populus trichocarpa likely driven by Helitrons

The model woody plant Populus trichocarpa displays an atypical alkene-diverse wax cuticle likely driven by copy number variation (CNV) of 3-ketoacyl-CoA synthases ( KCS ), which has been difficult to confirm with short-read assemblies. Long-read sequencing enables the development of telomere-to-telomere resources to detect cryptic variation, including CNVs, which are currently missed. Integrating this information can improve genomic prediction for breeding and provide insights into the evolutionary basis of important traits. Our analysis of 78 long-read haplotypes from chromosome 10 identified more than twice as many KCS genes as previously reported, and numerous intragenic non-synonymous substitutions. Random Forest predictive models highlighted the importance of Potri.010G079500 in producing very long chain alkenes; however, its absence did not predict previously reported alkene-deficient phenotypes. Instead, alkene levels are best predicted by the combinations of KCS copies. Additionally, amino acid substitutions clustered around ligand and donor binding pockets, suggesting they contribute to differing wax cuticle composition. Finally, each KCS gene and copy was linked to a Helitron transposon. A phylogenetic analysis suggests Helitrons are the evolutionary mechanism for generating KCS tandem arrays. Long-read generated telomere-to-telomere assemblies of P. trichocarpa chromosome 10 revealed large-effect loci critical to genetic studies that are unattainable from short-reads. This new resource produced novel insights into genome structure and function, and a novel mechanism for generating tandem gene duplication. Our results highlight that, given current challenges in annotation and assembly, detailed and focused long-read sequences are key to interpreting complex genomic regions that contain tandem copy number variants.

09 BIOMASS FUELS

Tooling concepts for assembly of large structures

Manufacture of the S-IC stage of the Saturn V space vehicle has resulted in new. concepts and innovations in the field of tooling. The structure size (35-ft diameter), the high reliability and accuracy requirements, and the low density or production quantity lead to a greater degree of simplicity, economy, and versatility in fabrication and assembly tooling. There are three specific concepts which should be applicable in industry, local jigging for welding, rotation of structures in vertical assemblies, and the assembly of two structures. The usual weld jigging serves a two-fold purpose: (a) to support the molten weld puddle and (b) to force and maintain alinement of the parts being welded. The extension of this method to large-diameter tanks is expensive and difficult. An alternate procedure used at MSFC is to perform free-state welding and use local jigging (stra1rclamps) and intermittent tack welding. Cylindrical structures can be accurately rotated for routing or welding on a simplified ring turntable. The tool consists of a ring of the structure diameter resting on rollers. Torque is nearly zero since the ring is rotated by friction rollers with the force being applied at the ring perimeter. Two such turntables are used at MSFC. The horizontal mating of two large components, where controlled motions of small magnitude are necessary, can be easily done by positioning units equipped with air-bearings. Such bearings are usable on concrete of minimum surface preparation and require no special air pressure source. This concept is used in assembly of the two S-IC containers.

Saturn S-IC stage