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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Direct time-resolved detection and quantification of key reactive intermediates in diethyl ether oxidation at T = 450–600 K

High-pressure multiplexed photoionization mass spectrometry (MPIMS) with tunable vacuum ultraviolet (VUV) ionization radiation from the Lawrence Berkeley Labs Advanced Light Source is used to investigate the oxidation of diethyl ether (DEE). Kinetics and photoionization (PI) spectra are simultaneously measured for the species formed. Several stable products from DEE oxidation are identified and quantified using reference PI cross-sections. In addition, we directly detect and quantify three key chemical intermediates: peroxy (ROO˙), hydroperoxyalkyl peroxy (˙OOQOOH), and ketohydroperoxide (HOOP[double bond, length as m-dash]O, KHP). These intermediates undergo dissociative ionization (DI) into smaller fragments, making their identification by mass spectrometry challenging. Furthermore, with the aid of quantum chemical calculations, we identify the DI channels of these key chemical species and quantify their time-resolved concentrations from the overall carbon atom balance at T = 450 K and P = 7500 torr. This allows the determination of the absolute PI cross-sections of ROO˙, ˙OOQOOH, and KHP into each DI channel directly from experiment. The PI cross-sections in turn enable the quantification of ROO˙, ˙OOQOOH, and KHP from DEE oxidation over a range of experimental conditions that reveal the effects of pressure, O 2 concentration, and temperature on the competition among radical decomposition and second O 2 addition pathways.

42 ENGINEERING↗
DOE OSTI2024

Toward an integrated multi-gigahertz ionizing particle diagnostic

Needs arising at both current and future accelerator facilities call for the development of radiation-hardened position-sensing diagnostics that can operate with multi-GHz repetition rates. Such instruments are likely to also have applications in the diagnosis of rapid plasma behavior. Here, building on the recent work of our Advanced Accelerator Diagnostics Collaboration, we are exploring the development of integrated multi-GHz ionizing particle detection systems based on chemical-vapor deposition diamond sensors, with the initial goal of producing a quadrant detector that can determine the intensity and centroid position of a particle beam at a repetition rate between 5 and 10 GHz. Results from our initial high-speed characterization work are presented, including those from a single-channel sensor with a GHz response. Approaches to achieving multi-GHz (5–10 GHz) rate capability, including the design of a dedicated Application Specific Integrated Circuit and the use of 3D RF-solver computer aided design software, are presented and discussed in more detail. 3D RF simulations suggest clean pulses of duration less than 250 ps (FWHM less than 125 ps) can be achieved with the approaches developed by this work.

43 PARTICLE ACCELERATORS↗
DOE OSTI2024

On-demand fabrication of piezoelectric sensors for in-space structural health monitoring

Abstract Inflatable structures, promising for future deep space exploration missions, are vulnerable to damage from micrometeoroid and orbital debris impacts. Polyvinylidene fluoride-trifluoroethylene (PVDF-trFE) is a flexible, biocompatible, and chemical-resistant material capable of detecting impact forces due to its piezoelectric properties. This study used a state-of-the-art material extrusion system that has been validated for in-space manufacturing, to facilitate fast-prototyping of consistent and uniform PVDF-trFE films. By systematically investigating ink synthesis, printer settings, and post-processing conditions, this research established a comprehensive understanding of the process-structure-property relationship of printed PVDF-trFE. Consequently, this study consistently achieved the printing of PVDF-trFE films with a thickness of around 40 µ m, accompanied by an impressive piezoelectric coefficient of up to 25 pC N −1 . Additionally, an all-printed dynamic force sensor, featuring a sensitivity of 1.18 V N −1 , was produced by mix printing commercial electrically-conductive silver inks with the customized PVDF-trFE inks. This pioneering on-demand fabrication technique for PVDF-trFE films empowers future astronauts to design and manufacture piezoelectric sensors while in space, thereby significantly enhancing the affordability and sustainability of deep space exploration missions.

Instruments & Instrumentation↗
DOE OSTI2024

Fueling the Future: The Emergence of Self-Powered Enzymatic Biofuel Cell Biosensors

Self-powered biosensors are innovative devices that can detect and analyze biological or chemical substances without the need for an external power source. These biosensors can convert energy from the surrounding environment or the analyte itself into electrical signals for sensing and data transmission. The self-powered nature of these biosensors offers several advantages, such as portability, autonomy, and reduced waste generation from disposable batteries. They find applications in various fields, including healthcare, environmental monitoring, food safety, and wearable devices. While self-powered biosensors are a promising technology, there are still challenges to address, such as improving energy efficiency, sensitivity, and stability to make them more practical and widely adopted. This review article focuses on exploring the evolving trends in self-powered biosensor design, outlining potential advantages and limitations. With a focal point on enzymatic biofuel cell power generation, this article describes various sensing mechanisms that employ the analyte as substrate or fuel for the biocatalyst’s ability to generate current. Technical aspects of biofuel cells are also examined. Research and development in the field of self-powered biosensors is ongoing, and this review describes promising areas for further exploration within the field, identifying underexplored areas that could benefit from further investigation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Multiaxis sensing system for detection of airborne molecules and radionuclides

Various technologies presented herein relate to a method and equipment for detecting both airborne radioisotope and molecular effluent gases. Multi-Axis Sensing can be conducted by utilizing a pressurized MOF sorbent, such as a scintillating Metal-Organic Frameworks (S-MOFs). These MOFs are crystalline nanoporous materials that have synthetic versatility that allow adjustment of pore size, chemical environment, and luminescence properties. A method for detecting an analyte in a fluid sample is provided that comprises: loading a sorbent with a sample fluid, wherein the sorbent comprises a MOF material; pressurizing the sample fluid to increase the fluid in the sorbent thereby making a pressurized sorbent; and detecting ionizing radiation or a chemical property of the analyte in the pressurized sorbent.

Allendorf, Mark D.↗
DOE OSTI2026

An Infrared Database of n/k Optical Constants for Calculating Aerosol Spectra for the PICARD Program

The objective of the PICARD Program is to develop fieldable sensing platforms for the rapid chemical identification of aerosol particles in plumes. Standoff detection involves interrogating the aerosol cloud from a distance using optical methods and probing the signal returned from direct backscattering from the aerosol particles or transmitted through the plume after reflection from a retroreflector or surface of opportunity (SOO). The identification of chemical species, however, in aerosols is complicated by their complex compositions and morphologies, chemical interferants, and non-uniform particle sizes. To advance standoff detection of aerosols, modelling the infrared transmittance, reflectance and scattering spectra of aerosolized liquid and solid chemical compounds is required, and then testing that model experimentally via laboratory and field experiments. To perform accurate modeling, the infrared optical constants (n/k), i.e., the complex refractive index, of the compounds of interest are required. Thus, PNNL was tasked to provide the optical constants for a set of analytes relevant to the PICARD program. This report describes the experimental techniques used to derive the optical constants of both liquid and solid compounds using established “gold-standard” protocols, how the experimental data are processed to produce the wavenumber dependent optical constant vectors, and how the data are used in the aerosol absorption spectra modeling.

complex refractive index↗
DOE OSTI2022

Solid state NMR Investigation of Structural Differences in Pelletized DEB Samples

Upon hydrogenation of DEB pellets, which are composed of 75% virgin DEB and 25% of nanometer scale Pd catalysts on activated carbon, the uptake rate is strong, and the hydrogenation process is fast. However, the last batch of DEB pellets from KCNSC uptakes 10 times slower than traditional DEB pellets after ~ 50% consumption. In addition, the last batch of DEB getter pellets also became partially molten/wet during the hydrogenation process. This molten/wet phase during hydrogenation has only been observed with DPB and never with DEB formulation. DRIFT (diffuse reflection infrared Fourier transform) and XRD (x-ray diffraction) confirm that the questionable batch of DEB pellets from KCNSC are truly 100% DEB and not a mixture of DEB and DPB. So, there must be something different in the composition (like concentration and distribution of Pd) or interaction between the DEB molecules with the surrounding environment (activated carbon spreading medium). The possibility of some chemical contamination in the processing of this batch of questionable DEB getter pellets also comes to mind. Due to the ability of NMR to detect intermolecular interaction and sensitivity to small chemical concentration, NMR investigation was requested for this questionable batch of DEB getter pellets from KCNSC.

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

Characterizing the solid hydrolysis product, UF 4 (H 2 O) 2.5 , generated from neat water reactions with UF 4 at room temperature

Uranium tetrafluoride (UF 4 ) is an important intermediate in the production of UF 6 and uranium metal. Room temperature hydrolysis of UF 4 was investigated using a combination of Fluorine-19 nuclear magnetic resonance spectroscopy ( 19 F NMR), Raman and infrared spectroscopy, powder X-ray diffraction, and microscopy measurements. UF 4 (H 2 O) 2.5 was identified as the primary solid hydrolysis product when anhydrous UF 4 was stirred in deionized water. Static NMR and 19 F magic angle spinning NMR measurements revealed that a small amount of uranyl fluoride can also form when anhydrous UF 4 is left in water, although this species comprises less than 5% of the total sample with the remaining parts being UF 4 (H 2 O) 2.5 . Since UF 4 is generally considered to be stable under ambient conditions, these findings mark the first time that a room temperature reaction between UF 4 and water has been detected and analyzed without interference from additional chemical reagents. The Raman characterization of UF 4 (H 2 O) 2.5 presented herein is the first on record. Since UF 4 is one of the most used intermediates during chemical conversion of uranium ore to uranium metal for nuclear fuel and weapons, the results presented herein are applicable to numerous nuclear science fields where solid state detection of uranium is of value, including nuclear nonproliferation, nuclear forensics, and environmental remediation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Dynamically tunable membrane metasurfaces for infrared spectroscopy and strong light-matter interactions

Mid-infrared spectroscopy enables biochemical sensing by identifying vibrational molecular fingerprints, but it faces limitations in instrumentation portability and analytical sensitivity. Optical metasurfaces with strong mid-infrared photonic resonances provide an attractive solution towards on-chip spectrometry and sensitive molecular detection, yet their static nature hinders their anticipated impact. Here, we introduce and demonstrate dynamically tunable silicon membrane metasurfaces exhibiting high-Q transmissive resonances in the fingerprint region. By harnessing silicon’s thermo-optical properties, we achieve continuous modulation of coupling-induced transparency (CIT) modes that emerge upon the interference of quasi-bound states in the continuum (q-BICs) and surface lattice modes (SLMs). We measure a spectral tuning rate of 0.06 cm −1 K −1 by continuously sweeping the sharp CIT resonances over a 23.5 cm −1 spectral range across a temperature range of 300–700 K. In the current proof‑of‑concept implementation, the dynamic transmission control enables non-contact chemical analysis of polymer films by detecting characteristic absorption bands of polystyrene (1450 and 1492 cm −1 ) and poly(methyl methacrylate) (1730 cm −1 ) without requiring conventional spectrometers. When analyte molecules fill the metasurface-generated photonic cavities, we demonstrate vibrational strong coupling between the poly(methyl methacrylate)’s carbonyl band and the CIT mode, manifested in a Rabi splitting of ~43 cm −1 . Our results establish a new photonic platform that unites spectral precision, strong field enhancement, and reconfigurability, offering diverse potential for compact mid-infrared spectroscopy, molecular sensing, and programmable polaritonic photonics.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2025

Versatile & Intelligent Biodetection via Environmental Sensing (VIBES)

Reactive health monitoring strategies during events like the COVID-19 pandemic highlighted the need for predictive, threat-agnostic diagnostics that can detect both known diseases and novel chemical or biological threats. To address this, we investigated an optical biosensor as a breath volatile organic compound (VOC) analyzer, aiming to emulate biological olfaction. We assembled and validated the device with thin film metal coated substrate-based sensors. We immobilized small biological recognition elements on the substrates and delivered controlled concentrations of target VOCs. The sensor was irradiated with a visible laser and the sensor signal was recorded. We characterized the laser performance and tested 3 recognition elements for 2 VOCs with varying concentrations (1-100 ppm). We also evaluated enhancement of the signal using nanostructures on the metal film in comparison with planar film substrate. We demonstrated detecting ethanol reliably at concentrations as low as ~2 ppm along with preliminary detection of acetone (<100 ppm). We also found several unexpected factors that influence the sensor behavior that should be addressed to further refine the device’s performance. The nanostructures were, as expected, found to amplify the sensor signals. These findings demonstrate the feasibility of the optical bio-sensing modality for breath VOC monitoring at physiologically relevant levels. This positions LLNL to develop a low-cost, scalable, broad-spectrum health monitoring capability aligned with the Early Detection thrust of the Bioresilience Mission Focus Area and attract external funding.

47 OTHER INSTRUMENTATION↗
DOE OSTI2024

Geochemical-hydromechanical couplings during water-serpentinized harzburgite interactions at 20° C and 30 bars

Interaction of groundwater with the serpentinized harzburgites of the upper mantle plays an important role in the geologic carbon cycle and serpentinization processes. Here, in this study, an intact serpentinized harzburgite with more than 60% lizardite from the Semail ophiolite in Oman was reacted with water at near neutral pH and low PCO 2 to observe its dissolution behavior and reaction path within the CaO-MgO-SiO 2 -CO 2 -H 2 O system at 20 °C and 30 bars. In the experiment, mass (i.e. H 2 O, ions) transfer is by diffusion and the selected temperature and pressure conditions mimic water-rock interactions at the shallow portions of most ultramafic rock hosted aquifers. Equilibrium activity-activity diagrams and thermodynamic data were used to compare the experimentally determined reaction path with the theoretical stability boundaries for minerals involved to investigate the evolution of bulk chemical composition, mineralogy, and water composition. The experiments demonstrated that (i) the water-rock interactions increased the pH of the aqueous phase from 5.9 to 7.5 over a period of 18 weeks; (ii) the dissolution of lizardite, orthopyroxene (enstatite), and clinopyroxene (diopside and augite) increased the concentration of Mg, Ca, and Si in the aqueous phase; (iii) the dissolution was incongruent with respect to Mg and Si, favoring Si release at pH > 6 due to (a) breaking of more reactive cation‑oxygen bonds that is consistent with the stoichiometry of magnesium for proton exchange reaction which favors a surface that is enriched in Mg at basic conditions, and (b) preferential dissolution of clinopyroxene Mg 1.30 Ca 0.52 Fe 0.06 Si 2 O 6 ; (iv) the aqueous phase was undersaturated with respect to carbonate (e.g. calcite, magnesite, and hydromagnesite) and hydrous (e.g. lizardite, chrysotile, brucite, and talc) minerals; (v) the bulk chemical composition and mineralogy of the intact serpentinized harzburgite matrix did not change; (vi) the thermodynamic data can successfully predict water-intact serpentinized harzburgite behavior if the water chemical composition can be constrained; and (vii) no detectable macroscopic form of damage (e.g. microcracks forming as a result of differential stress fields due to changes in volume during chemical reaction) was observed.

Carbonation↗
DOE OSTI2022

Monitoring SARS-CoV-2 in wastewater [Slides]

The monitoring of SARS-CoV-2 through individual testing is subject to inaccuracies. Wastewater biosurveillance has been used around the world to detect the presence of drugs, viruses, and other chemicals present in a population. Fecal shedding of SARS-CoV-2 implies that wastewater can be analyzed in order to detect varying levels of the virus within a given community. Pepper Mild Mottle Virus is present consistently in human fecal matter, and can be used to normalize the amount of SARS-CoV-2 detected. In this experiment, the amount of SARS-CoV-2 in the wastewater sample was compared to the amount of PMMoV present. Wastewater samples were separated into three fractions: direct wastewater, a solid pellet, and filter paper extract. An RT-qPCR test was used on the extracted RNA from each fraction to detect the relative amount of SARS-CoV-2 and PMMoV copies in each sample. The amount of SARS-CoV-2 was successfully normalized to the amount of PMMoV.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

Monitoring SARS-CoV-2 in wastewater

The detection of SARS-CoV-2 cases throughout the pandemic has been based on individual testing, which is subject to inaccuracies in what is actually occurring within the local population. Wastewater biosurveillance has been used around the world to detect the presence of drugs, viruses, and other chemicals present in a population. Fecal shedding of SARS-CoV-2 implies that wastewater can be analyzed in order to detect varying levels of the virus within a given community. This analysis can show the fluctuation of SARS-CoV-2 at a population level over time. In this experiment, the amount of SARS-CoV-2 in the wastewater sample was compared to the amount of Pepper Mild Mottle Virus (PMMoV) detected in the same sample. PMMoV is present consistently in human fecal matter, and can be used to normalize the amount of SARS-CoV-2 detected in wastewater.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2025

Uncertainty improvement of 22 Na based radioactive tracer dilution for determining total mass of pyroprocessing molten salt systems by 154 Eu removal

To determine the total salt mass of the molten salt systems for pyroprocessing spent nuclear fuels, a 22 Na based radioactive tracer dilution was studied in Idaho National Laboratory in recent years. This 22 Na based RTD technique was deemed feasible, but due to the gamma energy peak of 22 Na coinciding with one of the energy peaks of 154 Eu radioisotope in the molten salt, the uncertainty of the 22 Na radioactivity in the 22 Na-spiked salt samples was quite high. To improve the uncertainty of the 22 Na based RTD technique, we proposed to chemically remove the 154 Eu of the salt samples by DGA resin for gamma spectroscopy. The effectiveness of removing 154 Eu on uncertainty improvement was evaluated. Furthermore, it was found that (1) the 154 Eu fission product effect on the uncertainty and detection limit can be effectively eliminated by chemically removing the 154 Eu during the salt sample preparation and (2) the uncertainty of 22 Na radioactivity in the salt samples for electrorefining was significantly improved from 13% to 2%, showing the potential of practical engineering application of 22 Na based RTD as a safeguards technique for molten salt systems for pyroprocessing spent nuclear fuels.

11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2024

Mid-infrared trace detection with parts-per-quadrillion quantitation accuracy: Expanding frontiers of radiocarbon sensing

Detection sensitivity is a critical characteristic to consider during selection of spectroscopic techniques. However, high sensitivity alone is insufficient for spectroscopic measurements in spectrally congested regions. Two-color cavity ringdown spectroscopy (2C-CRDS), based on intra-cavity pump–probe detection, simultaneously achieves high detection sensitivity and selectivity. This combination enables mid-infrared detection of radiocarbon dioxide ( 14 CO 2 ) molecules in room-temperature CO 2 samples, with 1.4 parts-per-quadrillion (ppq, 10 − 15 ) sensitivity (average measurement precision) and 4.6-ppq quantitation accuracy (average calibrated measurement error for 21 samples from four separate trials) demonstrated on samples with 14 C/C up to ∼ 1.5 × natural abundance ( ∼ 1,800 ppq). These highly reproducible measurements, which are the most sensitive and quantitatively accurate in the mid-infrared, are accomplished despite the presence of orders-of-magnitude stronger, one-photon signals from other CO 2 isotopologues. This is a major achievement in laser spectroscopy. A room-temperature-operated, compact, and low-cost 2C-CRDS sensor for 14 CO 2 benefits a wide range of scientific fields that utilize 14 C for dating and isotope tracing, most notably atmospheric 14 CO 2 monitoring to track CO 2 emissions from fossil fuels. The 2C-CRDS technique significantly enhances the general utility of high-resolution mid-infrared detection for analytical measurements and fundamental chemical dynamics studies.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2025

Gas-phase synthesis of anthracene and phenanthrene via radical-radical reaction induced ring expansions

Unraveling reaction mechanisms of aromatic and resonance-stabilized radicals is critical to understanding molecular mass growth processes to polycyclic aromatic hydrocarbons (PAHs) and carbonaceous nanoparticles in distinct astrophysical environments (molecular clouds, circumstellar envelopes) and combustion systems. Using photoelectron photoion coincidence spectroscopy (PEPICO), we explored the gas-phase reaction of the methyl radical (CH 3 • ) with the aromatic and resonance-stabilized fluorenyl radical (C 13 H 9 • ) under high-temperature conditions in a chemical microreactor. Anthracene and phenanthrene were detected isomer-selectively using photoionization efficiency (PIE) curves and mass-selected threshold photoelectron (ms-TPE) spectra. While phenanthrene is produced through a radical-radical recombination of the carbon-centered radicals, anthracene may plausibly be formed through an unconventional radical addition to a low spin-density fluorenyl carbon. These pathways result in five-membered ring expansion—a critical mechanism crucial to PAH mass growth converting bent PAHs into planar nanostructures.

Goettl, Shane J. [University of Hawai‘i at Mānoa, ↗
DOE OSTI2020

Development of Anti- Yersinia pestis Human Antibodies with Features Required for Diagnostic and Therapeutic Applications

Yersinia pestis is a category A infective agent that causes bubonic, septicemic, and pneumonic plague. Notably, the acquisition of antimicrobial or multidrug resistance through natural or purposed means qualifies Y. pestis as a potential biothreat agent. Therefore, high-quality antibodies designed for accurate and sensitive Y. pestis diagnostics, and therapeutics potentiating or replacing traditional antibiotics are of utmost need for national security and public health preparedness. Here, we describe a set of human monoclonal immunoglobulins (IgG1s) targeting Y. pestis fraction 1 (F1) antigen, previously derived from in vitro evolution of a phage-display library of single-chain antibodies (scFv). We extensively characterized these antibodies and their effect on bacterial and mammalian cells via: ELISA, flow cytometry, mass spectrometry, spectroscopy, and various metabolic assays. Two of our anti-F1 IgG (αF1Ig 2 and αF1Ig 8) stood out for high production yield, specificity, and stability. These two antibodies were additionally attractive in that they displayed picomolar affinity, did not compete when binding Y. pestis, and retained immunoreactivity upon chemical derivatization. Most importantly, these antibodies detected < 1,000 Y. pestis cells in sandwich ELISA, did not harm respiratory epithelial cells, induced Y. pestis agglutination at low concentration (350 nM), and caused apparent reduction in cell growth when radiolabeled at a nonagglutinating concentration (34 nM). These antibodies are amenable to the development of accurate and sensitive diagnostics and immuno/radioimmunotherapeutics.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Ionic liquid carbon nanotube composites for wireless chemical sensing

A wireless sensor platform design and a single walled carbon nanotube/ionic liquid-based chemidosimeter system can incorporated into a highly sensitive and selective chemical hazard badge that can dosimetrically detect an analyte down to a sub parts-per-million concentration.

Swager, Timothy M.↗