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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Poly(lactic acid)-Based Ink for Biodegradable Printed Electronics With Conductivity Enhanced through Solvent Aging

Biodegradable electronics is a rapidly growing field, and the development of controllably biodegradable, high-conductivity materials suitable for additive manufacturing under ambient conditions remains a challenge. Here, printable conductive pastes that employ poly(lactic acid) (PLA) as a binder and tungsten as a conductor are demonstrated. These composite conductors can provide enhanced stability in applications where moisture may be present, such as environmental monitoring or agriculture. Post-processing the printed traces using a solvent-aging technique increases their conductivity by up to 2 orders of magnitude, with final conductivities approaching 5000 S/m. Such techniques could prove useful when thermal processes including heating or laser sintering are limited by the temperature constraints of typical biodegradable substrates. Finally, both accelerated oxidative and hydrolytic degradation of the printed composite conductors are examined, and a fully biodegradable capacitive soil moisture sensor is fabricated and tested.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Assembly of Disordered Cocontinuous Morphologies by Multiblock Copolymers with Random Block Sequence and Length Dispersity

Among the wide variety of nanostructures accessible by self-assembly of block copolymers, cocontinuous morphologies are of great interest for separations, catalysis, sensing, and energy storage due to their ability to integrate distinct properties of the constituent polymers. Furthermore, we investigate the tendency to form disordered cocontinuous phases of multiblock copolymers (MBCs) with random block sequence and length dispersity prepared by step-growth polymerization of pre-made telechelic polymers, specifically using thiol-Michael addition between diacrylate functionalized polystyrene (PS) and poly (D,L - lactide) (PLA) chains and a small molecule dithiol. In the phase diagram so established, disordered cocontinuous nanostructures occupy a wide window (≈ 25 % vol) at a modest segregation strength of χN = 15, close to the critical value for microphase separation. At a higher segregation strength of χN = 30, only a moderately wide (≈ 10 vol %) cocontinuous window is found, with MBCs instead tending to form ordered nanostructures. Although the breadth of the cocontinuous widow is less than that found in prior work on analogous randomly end-linked copolymer networks (RECNs), the MBC architecture offers offsetting advantages in terms of solution and melt processability.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Regio- and Stereoselective Lactone Polymerization: Divergent Effect of Catalyst Modification and Monomer Structure

Selective ring-opening polymerization (ROP) of chiral lactones enables access to biodegradable polyesters with precisely controlled microstructures. Here, combined DFT modeling and experimental validation elucidate how fine-tuning of enantiopure SalBinam aluminum catalysts (through introduction of bromine atoms and tert-butyl groups, respectively, in ortho- and para-positions) modulates regio- and stereocontrol in the ROP of methyl glycolide (MeG) and lactide (LA). Computations reveal that regioselectivity in MeG polymerization arises mainly from steric repulsion, with a small contribution from weak stabilizing C-H···Br interactions that favor ring-opening at the glycolic site, consistent with the experimentally enhanced regioselectivity for (R)-MeG. In contrast, the same steric congestion at the ligand’s ortho positions destabilizes the key transition states in rac-LA polymerization, reducing the calculated stereoselectivity. Experiments confirm the predicted loss of stereocontrol, yielding nearly atactic PLA under standard conditions. Extension of the computational framework to rac-MeG polymerization promoted by racemic catalyst identified a low-barrier, stepwise polymer chain exchange pathway that rationalizes the experimentally observed syndiotacticity of poly(lactic-co-glycolic acid).

DFT calculations↗
DOE OSTI2023

Depolymerization of polyesters by a binuclear catalyst for plastic recycling

Plastics play an essential role in modern society, however, the relentless growth of their production is threatening both human health and ecosystems. As a result, there are intensive efforts in developing recycling technologies to repurpose waste plastics into the building blocks for valuable materials. Here we show a binuclear complex that can catalyze the degradation of polyethylene terephthalate (PET)-the most widely used polyester globally-and a wide spectrum of other plastics including polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polycaprolactone (PCL), polyurethane (PU) and Nylon 66. Inspired by hydrolases, the group of enzymes that catalyze bond cleavages with water, the present catalyst design features biomimetic Zn-Zn sites which activate the plastic, stabilize the key intermediate, and enable intramolecular hydrolysis. This synthetic catalyst delivers activities of 36 mg PET d -1 g catal -1 toward PET depolymerization at pH 8 and 40 oC, and of 577 g PET d -1 g catal -1 at pH 13 and 90 oC for scalable PET recycling. We further demonstrate the closed-loop production of a bottle-grade PET. This work presents a practical and viable solution to the sustainable management of plastics waste.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Structure-guided functional studies of plasmid-encoded dihydrofolate reductases reveal a common mechanism of trimethoprim resistance in Gram-negative pathogens

Two plasmid-encoded dihydrofolate reductase (DHFR) isoforms, DfrA1 and DfrA5, that give rise to high levels of resistance in Gram-negative bacteria were structurally and biochemically characterized to reveal the mechanism of TMP resistance and to support phylogenic groupings for drug development against antibiotic resistant pathogens. Preliminary screening of novel antifolates revealed related chemotypes that showed high levels of inhibitory potency against Escherichia coli chromosomal DHFR (EcDHFR), DfrA1, and DfrA5. Kinetics and biophysical analysis, coupled with crystal structures of trimethoprim bound to EcDHFR, DfrA1 and DfrA5, and two propargyl-linked antifolates (PLA) complexed with EcDHFR, DfrA1 and DfrA5, were determined to define structural features of the substrate binding pocket and guide synthesis of pan-DHFR inhibitors.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2025

Sustainable upcycling of polyethylene waste to compatibilizers and valuable chemicals

Controllable functionalization of polyethylene (PE) waste could generate new polymeric materials that are generally difficult to manufacture sustainably while also addressing the growing plastics waste problem. However, these modifications remain challenging due to the inherent stability of the PE backbone. Non-thermal atmospheric plasma enables molecular activation under mild conditions while utilizing renewable energy but is primarily employed for surface modification, as plasmas do not penetrate the bulk of materials. Herein, controllable bulk oxidative functionalization of PE wax (PEW) and low-density PE (LDPE) of varying molecular weights was achieved, with up to 6 mol% oxygen incorporation, by manipulating melt viscosity. This functionalization was accomplished either through temperature adjustment or by introducing a melt viscosity modifier, removable via simple extraction methods, to reduce LDPE viscosity, enhance diffusion and chain mobility, and enable bulk oxidation. The oxidized LDPE induces compatibilization in blends of poly(lactic acid) (PLA) and LDPE with improved interfacial adhesion and mechanical properties, such as a 70% increase in elongation-at-break values vs. the control. These findings pave the way for catalyst-free upcycling of direct plastics waste and plastics waste-derived products, enabling the creation of high-value products across various markets.

Plastic upcycling↗
DOE OSTI2022

Experimental Verification of Pulse Shaping in Elastic Metamaterials Under Impact Excitation

Here, we present experimental verification of pulse shaping in elastic metamaterials together with a procedure to design, fabricate, and verify metamaterial pulse shapers under impact excitation. The split Hopkinson pressure bar (SHPB) test, a fundamental dynamic test introduced more than 70 years ago, often incorporates pulse shaping as a means to alter a stress wave, providing the primary motivation for the presented study. Elastic metamaterials hold promise for enhancing conventional pulse shaping abilities and improving capabilities of the SHPB test. We first design the pulse shaper by numerically optimizing its response using finite element analysis. The pulse shaper consists of repeated unit cells based on a combination of a phononic crystal and a local resonator. Then, we fabricate and test pulse shaper candidates to validate the procedural efficacy. An iterative element corrects inaccuracies in input force and material properties and allows convergence on an appropriate pulse shaper. We carry out this procedure by designing pulse shapers fabricated from 3D-printed polylactic acid (PLA) to achieve an extended dwell acceleration pulse shape. In experimental impact tests, the procedure results in rise, dwell, and fall behaviors comparable to that predicted, effectively confirming the efficacy of the presented procedure and verifying the performance of metamaterial-based pulse shapers.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Thermal images collected during large-scale 3D printing with Ingersoll MasterPrint

This data set contains images produced to test the performance of anomaly and fault detection methods in the context of additive manufacturing. Two print jobs were executed using the Ingersoll MasterPrint with the Model 30 Strangpresse extruder. The material used was Techmer compounded polylactic acid (PLA) with wood flour as a filler (80/20 PLA/WF by weight). The first print job consists of the 3D printing of a hexagonal cylinder with a two-bead wall. This print was sliced at a gantry velocity of 3000 millimeter per minute, and an extruder screw speed of 68.14 rotations per minute. This are considered the normal operating conditions. A second hexagonal cylinder was printed using a reduced extruder screw speed, 15% lower than under normal operating conditions. The images were collected with a Teledyne FLIR Lepton 3.5 infra-red camera, a small form factor radiometric long-wave infrared camera with a spectral range of 8 µm to 14 µm. Sensor resolution was 160x120 pixels, with a pixel size of 12 µm, a temperature range of -10 - 450°C, and an accuracy of +/- 10°C in its low gain configuration. Images in this data set were collected with cameras oriented at the printer nozzle. The nozzle camera setup consisted of two cameras located 12.5cm from the nozzle center. These were mounted directly to the print head, so that the camera positions relative to the print direction would remain constant as it rotated around its C-axis to follow the print path. One camera was placed ahead of the nozzle to capture the previous layer immediately before being covered by the new layer of material, while the second camera was placed behind the nozzle and captured the freshly extruded bead. Images are collecting during each phase of the print: (a) idle (i.e., no material deposited), (b) extrusion (i.e., to prime the extruder), and (c) printing (deposition of material to manufacture the hexagonal cylinder).

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li6Co3P8O29 by Materials Project

Li6Co3P8O29 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are twelve inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two LiO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one CoO6 octahedra. There are a spread of Li–O bond distances ranging from 2.00–2.17 Å. In the second Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.92–2.19 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, an edgeedge with one LiO6 octahedra, and an edgeedge with one CoO6 octahedra. There are a spread of Li–O bond distances ranging from 1.94–2.07 Å. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, an edgeedge with one LiO6 octahedra, and an edgeedge with one CoO6 octahedra. There are a spread of Li–O bond distances ranging from 1.97–2.03 Å. In the fifth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two LiO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one CoO6 octahedra. There are a spread of Li–O bond distances ranging from 1.98–2.09 Å. In the sixth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one CoO6 octahedra. There are a spread of Li–O bond distances ranging from 1.90–2.22 Å. In the seventh Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with four PO4 tetrahedra, an edgeedge with one LiO6 octahedra, and an edgeedge with one CoO6 octahedra. There are a spread of Li–O bond distances ranging from 1.98–2.05 Å. In the eighth Li1+ site, Li1+ is bonded to six O2- atoms to form distorted LiO6 octahedra that share corners with six PO4 tetrahedra and edges with three LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 2.28–2.54 Å. In the ninth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with three CoO6 octahedra and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 65–67°. There are a spread of Li–O bond distances ranging from 1.93–2.13 Å. In the tenth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with three CoO6 octahedra and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 66–72°. There are a spread of Li–O bond distances ranging from 1.91–2.20 Å. In the eleventh Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.94–2.09 Å. In the twelfth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one CoO6 octahedra. There are a spread of Li–O bond distances ranging from 1.96–2.15 Å. There are six inequivalent Co4+ sites. In the first Co4+ site, Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.90–2.10 Å. In the second Co4+ site, Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, and edges with two LiO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.93–2.05 Å. In the third Co4+ site, Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one LiO4 tetrahedra and corners with six PO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.91–2.10 Å. In the fourth Co4+ site, Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.84–1.99 Å. In the fifth Co4+ site, Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.87–2.16 Å. In the sixth Co4+ site, Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one LiO4 tetrahedra, corners with six PO4 tetrahedra, and edges with two LiO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.90–2.06 Å. There are sixteen inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three CoO6 octahedra and corners with three LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 30–40°. There are a spread of P–O bond distances ranging from 1.54–1.59 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three CoO6 octahedra and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–39°. There are a spread of P–O bond distances ranging from 1.54–1.56 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three CoO6 octahedra and corners with three LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–41°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one LiO6 octahedra, corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–48°. There are a spread of P–O bond distances ranging from 1.52–1.60 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one LiO6 octahedra, corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–52°. There are a spread of P–O bond distances ranging from 1.51–1.62 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CoO6 octahedra, a cornercorner with one LiO4 tetrahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–46°. There are a spread of P–O bond distances ranging from 1.52–1.59 Å. In the seventh P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one LiO6 octahedra, corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with three LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–56°. There are a spread of P–O bond distances ranging from 1.52–1.61 Å. In the eighth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three CoO6 octahedra and a cornercorner with one LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–42°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the ninth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one LiO6 octahedra, corners with two CoO6 octahedra, a cornercorner with one LiO4 tetrahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–53°. There are a spread of P–O bond distances ranging from 1.52–1.62 Å. In the tenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–44°. There are a spread of P–O bond distances ranging from 1.51–1.62 Å. In the eleventh P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–52°. There are a spread of P–O bond distances ranging from 1.51–1.62 Å. In the twelfth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one LiO6 octahedra, corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–48°. There are a spread of P–O bond distances ranging from 1.51–1.63 Å. In the thirteenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one LiO6 octahedra, corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–47°. There are a spread of P–O bond distances ranging from 1.51–1.63 Å. In the fourteenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with three LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–50°. There are a spread of P–O bond distances ranging from 1.51–1.62 Å. In the fifteenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with three LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–48°. There are a spread of P–O bond distances ranging from 1.51–1.63 Å. In the sixteenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two CoO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with four LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–49°. There are a spread of P–O bond distances ranging from 1.51–1.61 Å. There are fifty-eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Co4+, and one P5+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two P5+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Co4+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a linear geometry to one Li1+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Co4+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Co4+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Co4+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Co4+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Co4+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to one Co4+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted trigonal pla

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li4V3P8O29 by Materials Project

Li4V3P8O29 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one VO6 octahedra. There are a spread of Li–O bond distances ranging from 1.99–2.24 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one VO6 octahedra. There are a spread of Li–O bond distances ranging from 1.99–2.24 Å. In the third Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.90–2.31 Å. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one VO6 octahedra. There are a spread of Li–O bond distances ranging from 1.88–2.28 Å. In the fifth Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.90–2.30 Å. In the sixth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, and an edgeedge with one VO6 octahedra. There are a spread of Li–O bond distances ranging from 1.88–2.28 Å. In the seventh Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with four PO4 tetrahedra and an edgeedge with one VO6 octahedra. There are a spread of Li–O bond distances ranging from 1.87–2.38 Å. In the eighth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with four PO4 tetrahedra and an edgeedge with one VO6 octahedra. There are a spread of Li–O bond distances ranging from 1.87–2.39 Å. There are six inequivalent V+4.67+ sites. In the first V+4.67+ site, V+4.67+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six PO4 tetrahedra and an edgeedge with one LiO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.83–1.97 Å. In the second V+4.67+ site, V+4.67+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six PO4 tetrahedra and edges with two LiO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.86–2.02 Å. In the third V+4.67+ site, V+4.67+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.85–1.97 Å. In the fourth V+4.67+ site, V+4.67+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.85–1.96 Å. In the fifth V+4.67+ site, V+4.67+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six PO4 tetrahedra and an edgeedge with one LiO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.83–1.97 Å. In the sixth V+4.67+ site, V+4.67+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six PO4 tetrahedra and edges with two LiO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.86–2.02 Å. There are sixteen inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–47°. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–47°. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one LiO4 tetrahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–47°. There are a spread of P–O bond distances ranging from 1.48–1.61 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three VO6 octahedra and a cornercorner with one LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–36°. There are a spread of P–O bond distances ranging from 1.48–1.60 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three VO6 octahedra and a cornercorner with one LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–36°. There are a spread of P–O bond distances ranging from 1.48–1.60 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–48°. There are a spread of P–O bond distances ranging from 1.48–1.62 Å. In the seventh P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one LiO4 tetrahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–43°. There are a spread of P–O bond distances ranging from 1.48–1.60 Å. In the eighth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one LiO4 tetrahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–47°. There are a spread of P–O bond distances ranging from 1.48–1.61 Å. In the ninth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–41°. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the tenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–48°. There are a spread of P–O bond distances ranging from 1.48–1.62 Å. In the eleventh P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one LiO4 tetrahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–43°. There are a spread of P–O bond distances ranging from 1.48–1.60 Å. In the twelfth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three VO6 octahedra and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–36°. There are a spread of P–O bond distances ranging from 1.49–1.59 Å. In the thirteenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three VO6 octahedra and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–36°. There are a spread of P–O bond distances ranging from 1.49–1.59 Å. In the fourteenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one PO4 tetrahedra, and corners with two LiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–41°. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the fifteenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one LiO4 tetrahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–41°. There are a spread of P–O bond distances ranging from 1.47–1.61 Å. In the sixteenth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two VO6 octahedra, a cornercorner with one LiO4 tetrahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–41°. There are a spread of P–O bond distances ranging from 1.47–1.61 Å. There are fifty-eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V+4.67+, and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V+4.67+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V+4.67+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V+4.67+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V+4.67+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the fifteenth O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the sixteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the nineteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V+4.67+, and one P5+ atom. In the twentieth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two P5+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one P5+ atom. In the twenty-second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one P5+ atom. In the twenty-third O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the twenty-fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the twenty-fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V+4.67+, and one P5+ atom. In the twenty-sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the twenty-seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the twenty-eighth O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one P5+ atom. In the twenty-ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one P5+ atom. In the thirtieth O2- site, O2- is bonded in a bent 150 degrees geometry to one V+4.67+ and one P5+ atom. In the thirty-first O2- site, O2- is bonded in a distorted trigonal pla

36 MATERIALS SCIENCE↗
DOE OSTI2022

Designing a Particle Flow Control Apparatus

Flow control within a particle-based Concentrated Solar Power (CSP) system is essential in determining the heat transfer coefficient, and therefore, the power generation capability of these systems. There are three areas where particle flow control is significant: the receivers, storage tanks, and particle-sCO2 heat exchangers. The focus of this work is on designing a new mechanism to control the flow in the particle-sCO2 heat exchangers due to the simplicity and potential cost savings when compared to the other areas of interest. The goal is for this new design to have quicker response times in terms of particle flowrate than a slide gate or flow control valve, which are designs currently used. The design resembles that of a chuck mechanism within a drill where a rotation of the sleeve elicits movement of the jaws both vertically and horizontally to close the outlet area of the nozzle. Additionally, this design will utilize the current actuator that is already used within these heat exchangers to reduce the complexity of implementation. The jaws are designed to be closed at an angle of 76˚ which is just slightly steeper than the hopper leading to the mechanism. Furthermore, this design can be tuned to limit particle bridging and other particle flow phenomena that result in blockages. The prototypes were 3D printed out of polylactic acid (PLA) and scaled up to 100%, 200%, and 400% to be able to observe the velocity profiles of the mechanism more clearly. Experiments are performed with this prototype to compare the inlet and outlet mass flow rates at different configurations of the jaws. The particles used in these experiments are 0.3mm HSP 40/70 that are commonly used in particle-based CSP systems.

14 SOLAR ENERGY↗
DOE OSTI2025

Degradable Biocomposite Thermoplastic Polyurethanes

In this project, the team developed tough and degradable biocomposite thermoplastic polyurethanes (TPUs) by incorporating bacterial spores into TPUs as a biofunctional living filler. The team screened various bacteria and selected the Bacillus subtilis ATCC 6633 strain as the final candidate, primarily due to its genomic availability, sporulation ability and TPU assimilation activity. The heat-shock tolerance of ATCC 6633 spores was further improved through evolutionary engineering via Adaptive Laboratory Evolution (ALE), demonstrating a 17.7-fold enhanced germination efficiency post heat-shock treatment compared to the wild-type strain (WT). The team fabricated biocomposite TPUs by incorporating lyophilized powder of heat-shock tolerized (HST) spores during the hot melt extrusion (HME) of TPU at 135 °C. The baseline TPU used in this project is a commercially available soft-grade TPU (BCF45) manufactured by BASF. Colony forming unit (CFU) assays quantified that WT and HST spores in the TPU matrix retained approximately 20% and 100% survivability, respectively, after HME. Tensile testing demonstrated that the spores behaved as a polymer-reinforcing filler, positively affecting the overall tensile properties of the biocomposite TPU. For example, biocomposite TPU with WT and HST spores (BC TPU WT and BC TPU HST , respectively) exhibited up to 25% and 37% improved toughness, respectively, compared to TPU without spores. BC TPU HST showed remarkably improved disintegration in autoclaved compost (92% mass loss in 5 months), which simulated a microbially poor environment for TPU degradation. When compared to TPU without spores (44% mass loss in 5 months) the acceleration of degradation is marked. Respirometry confirmed that 72% of BC TPU HST was biomineralized into CO2 within 6 months, indicating that spores in the biocomposite TPU were germinated by utilizing nutrients in the autoclaved compost, facilitating TPU degradation at the end of the material's life. The team demonstrated the scale-up of biocomposite TPU fabrication using continuous extrusion and injection molding techniques. Processing conditions optimized in a lab-scale microcompounder were successfully transferred to a continuous extruder with a 30-fold increased throughput. Biocomposite TPUs prepared using these industry-relevant processes showed comparable toughness improvements to samples prepared in the lab-scale extruder. Excitingly, following compounding in the pilot-extruder the composite material could be injection molded, while retaining high spore viability and similar toughness improvements. The team also found that spores in biocomposite TPU served as antioxidants, preventing toughness decay during the recycled extrusion of BC TPU HST . Long-term storage tests over one year showed that the addition of spores had no negative effect on the longevity of the TPU. Furthermore, the team demonstrated the fabrication of spore-bearing biocomposite polymers with other polyesters such as PBAT, PLA, and PCL. We obtained promising preliminary data that showed overall toughness improvements for all polymers with spore addition. Finally, life cycle assessment (LCA) and techno-economic analysis (TEA) were carried out, which indicated minimal additional cost of fabrication. Overall, a tough and degradable biocomposite thermoplastic was successfully developed through this project, with all tasks completed successfully, achieving >100% of the objectives.

36 MATERIALS SCIENCE↗
DOE OSTI2026

PIP-II LB650 Cryomodule Mockup

Fermilab’s PIP-II project requires accurate cable routing in the LB650 cryomodule, a confined and difficult-to-access system. We designed a full-scale mockup using a 15-ft, 7-ft 8020 frame and twenty-three PLA interfaces. CAD modeling and lifting analysis has been verified for safe assembly With all components ordered, the mockup will allow technicians to rehearse routing and identify issues before working on the real cryomodule.

Oribello, Francis [Northern Illinois U.]↗
DOE OSTI2026

Biodegradable Biocomposite Development for Large Scale Additive Manufacturing

Oak Ridge National Laboratory (ORNL) worked with Mitsubishi Chemical America, Inc. to develop a highly biodegradable ~100% biobased feedstock for large format additive manufacturing (AM). Together, they developed an AM feedstock based on the biobased polyester, polybutylene succinate (PBS), that is typically used in agriculture and packaging projects. The motivation for this work was to leverage the high degradability of this polymer in AM to create a new avenue for end-of-life disposal of the product. A composite feedstock was developed from PBS, polylactic acid (PLA), and wood flour (WF). While WF improves printability, reduces feedstock cost, and can improve stiffness, it also often results in a loss in tensile strength which can inhibit/limit applications of the material. To recover the loss in tensile strength suffered by including large quantities, up to 30 wt.% WF in the composite, a chain extender was used to compatibilize the different composite constituents with each other. The feedstock was used to 3D-print a demonstration mold for precast concrete catch basins and was tested by casting 750 lbs of concrete. The mold survived the demonstration. Aerobic degradation testing of the composite feedstock showed that it was highly degradable, 40% biodegradation after 90 days, compared to other incumbent biobased feedstocks.

100% biobased feedstock for large format additive ↗
DOE OSTI2026

Biodegradable Biocomposite Development for Large Scale Additive Manufacturing

Oak Ridge National Laboratory (ORNL) worked with Mitsubishi Chemical America, Inc. to develop a highly biodegradable ~100% biobased feedstock for large format additive manufacturing (AM). Together, they developed a AM feedstock based on the biobased polyester, polybutylene succinate (PBS), that is typically used in agriculture and packaging projects. The motivation for this work was to leverage the high degradability of this polymer in AM to create a new avenue for end-of-life disposal of the product. A composite feedstock was developed from PBS, polylactic acid (PLA), and wood flour (WF). While WF improves printability, reduces feedstock cost, and can improve stiffness, it also often results in a loss in tensile strength which can inhibit/limit application of the material. To recover the loss in tensile strength suffered by including large quantities, up to 30 wt%, WF in the composite a chain extender was used to compatibilze the different composite constituents with each other. The feedstock was used to 3D-print demonstration mold for precast concrete catch basins and was tested by casting 750 lbs of concrete. The mold survived the demonstration. Aerobic degradation testing of the composite feedstock showed that it was highly degradable, 40% biodegradation after 90 days, compared to other incumbent biobased feedstocks.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Using mechanistic models and machine learning to design single-color multiplexed nascent chain tracking experiments

mRNA translation is the ubiquitous cellular process of reading messenger-RNA strands into functional proteins. Over the past decade, large strides in microscopy techniques have allowed observation of mRNA translation at a single-molecule resolution for self-consistent time-series measurements in live cells. Dubbed Nascent chain tracking (NCT), these methods have explored many temporal dynamics in mRNA translation uncaptured by other experimental methods such as ribosomal profiling, smFISH, pSILAC, BONCAT, or FUNCAT-PLA. However, NCT is currently restricted to the observation of one or two mRNA species at a time due to limits in the number of resolvable fluorescent tags. In this work, we propose a hybrid computational pipeline, where detailed mechanistic simulations produce realistic NCT videos, and machine learning is used to assess potential experimental designs for their ability to resolve multiple mRNA species using a single fluorescent color for all species. Our simulation results show that with careful application this hybrid design strategy could in principle be used to extend the number of mRNA species that could be watched simultaneously within the same cell. We present a simulated example NCT experiment with seven different mRNA species within the same simulated cell and use our ML labeling to identify these spots with 90% accuracy using only two distinct fluorescent tags. We conclude that the proposed extension to the NCT color palette should allow experimentalists to access a plethora of new experimental design possibilities, especially for cell Signaling applications requiring simultaneous study of multiple mRNAs.

59 BASIC BIOLOGICAL SCIENCES↗