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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 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Life on Mars - How it disappeared (if it was ever there)

Information available on Mars chemistry suggest that conditions on early Mars may have been suitable for life. This paper examines the possible events that led to the disappearance of life, assuming it existed, from the surface of Mars. The sequence of events leading to life extinction on early Mars assumes the following steps: (1) a decrease of temperature and humidity levels, leading to a selection of microorganisms for tolerance of low temperatures and arid conditions; (2) further deterioration of environment leading to withdrawal of cold-adapted organisms to protected niches under the surface; (3) further cooling producing heavy stresses in these organisms; and (4) further deterioration of the environment resulting in extinction. This sequence of events is considered parallel events documented for the microbial community in the Ross Desert of Antarctica, where TEM examinations of the material detected progressive stages of cell damage and death.

Friedmann, E. Imre↗
NASA NTRS1985

Theoretical studies of the marine sulfur cycle

Several reduced sulfur compounds are produced by marine organisms and then enter the atmosphere, where they are oxidized and ultimately returned to the ocean or the land. The oceanic dimethyl sulfide (DMS) flux, in particular, represents a significant fraction of the annual global sulfur input to the atmosphere. In the atmosphere, this gas is converted to sulfur dioxide (SO2), methane sulfonic acid, and other organic acids which are relatively stable and about which little is known. SO2 is a short lived gas which, in turn, is converted to sulfuric acid and other sulfate compounds which contribute significantly to acid rain. Because of the complexity of the sulfur system, it is not well understood even in the unperturbed atmosphere. However, a number of new observations and experiments have led to a significant increase in the understanding of this system. A number of one dimensional model experiments were conducted on the gas phase part of the marine sulfur cycle. The results indicate the measured concentration of DMS and the amplitude of its diurnal cycle are in agreement with estimates of its global flux. It was also found that DMS can make a large contribution to the background SO2 concentration in the free troposphere. Estimates of CS2 concentrations in the atmosphere are inconsistent with estimated fluxes; however, measured reaction rates are consistent with the observed steep tropospheric gradient in CS2. Observations of CS2 are extremely sparse. Further study is planned.

Toon, Owen B.↗
DOE OSTI2024

The United States' (DOE) Action Plan for Power Sector Decarbonization

A collaborative report from the Clean Energy Ministerial (CEM) on Lessons Learned for Rapid Decarbonization of Power Sectors was delivered to energy ministers and presented at the 13th CEM (CEM13) in the United States in September 2022. In light of these lessons learned and discussed at CEM13, several jurisdictions signaled intent to develop Action Plans for power sector decarbonization. The first cohort of Action Plans was released at CEM14 in India in July 2023. The U.S. Department of Energy (DOE) is pleased to release this Action Plan as a contribution to the second cohort of Action Plans released at CEM15 in Brazil in October 2024. The Action Plans, supported by the 21st Century Power Partnership, and other CEM workstreams via direct technical assistance and capacity building, are intended to focus on select implementation actions, given each country's existing power sector goals and activities, and are an opportunity for countries to display leadership in power sector decarbonization. The Action Plans are organized in a framework for Planning, Building and Operating, as well as Stakeholder Engagement where appropriate based on country priorities. These Action Plans are voluntary, developed by each country individually, not comprehensive of all activities within the jurisdiction, and are living documents that are subject to change. This Action Plan, developed by DOE, is focused on federal actions for power sector decarbonization primarily led by DOE. There are many other actions being led by other U.S. government agencies, or at the state and local level, that are not featured in this Action Plan.

21st Century Power Partnership↗
DOE OSTI2025

Photo-Induced Hydrogen Production from Formic Acid Using a Palladium Catalyst

Liquid organic hydrogen carriers (LOHCs) are recognized as promising sustainable hydrogen (H 2 ) carriers due to their high volumetric capacity and ability to store H 2 at ambient conditions, eliminating the need for energy-intensive liquefaction or compression processes associated with H 2 or ammonia gas. One of the main current drawbacks, however, is LOHCs’ high energy demand for H 2 release. This work presents the photo-induced liberation of H 2 from formic acid (FA) as a liquid H 2 carrier, using visible light and well-established 5 wt% palladium nanoparticles supported over carbon (Pd/C). We show that low-power light-emitting diodes (LEDs) produced higher gas flow than their thermal baseline (35 °C), with 27.2 mL/min and 7.72 mL/min, respectively. Further, the rate of gas evolved with light intensity, catalyst loading, and the concentration of FA. Light-induced dehydrogenation shows similar deactivation as the known thermal mechanisms, such as the decreased Pd 2+ /Pd 0 ratio and Pd nanoparticle agglomeration. Hence, these observations suggest a photothermal mechanism, whereby the LED provides heat efficiently absorbed by the Pd/C catalyst and enhanced by Pd’s ability to absorb light, thereby driving the FA dehydrogenation reaction at ambient conditions.

08 HYDROGEN↗
DOE OSTI2025

Material Needs and Measurement Challenges for Advanced Semiconductor Packaging: Understanding the Soft Side of Science

This Perspective builds upon insights from the National Institute of Standards and Technology (NIST)-organized workshop, “Materials and Metrology Needs for Advanced Semiconductor Packaging Strategies,” held at the 35th annual Electronics Packaging Symposium in Binghamton, NY, on September 5, 2024. It outlines critical challenges and opportunities related to polymer-based “soft” materials in advanced semiconductor packaging, with emphasis on polymer science, measurement science (metrology), and the strategic development of Research-Grade Test Materials (RGTMs). These efforts, led by the NIST CHIPS team, aim to advance the fundamental understanding of structure-property-processing relationships, promote standardized guidelines and innovative methods for material characterization, and accelerate the development, qualification, and adoption of next-generation packaging materials. The Perspective also distills key insights from the panel discussion with industry experts, emphasizing the need for close collaboration among materials scientists, process engineers, and metrology experts to enable a holistic strategy, further highlighting the importance of cross-sector partnerships among industry, academia, and government to address pressing challenges in packaging materials and processes.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2015

Evaluation of Agricultural Sunflower Plants as Drought Tolerant Option For New Mexico Growers

The progressive drought in New Mexico has led farmers to consider crops that use less water yet maintain potential profit margins. Sunflower, a crop traditionally grown from Kansas to North Dakota, has recently been shown to be profitable in West Texas. The majority of sunflower is grown under dryland conditions due to its drought tolerance and deep root system. Sunflower was investigated as a new crop alternative for NM growers. Two organic, non-GMO seed varieties selected for the NM climate were planted at seven different farms across the state. Results from five of the farms were evaluated for biomass yield, oil yield, and oil characteristics. Results show promise for sunflower as a viable alternative for NM farmers to rotate into their crops.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Value and Role of Pumped Storage Hydro under High Variable Renewables

A project team, led by GE Research, was tasked by the U.S Department of Energy (DOE) to study the value and role of pumped storage hydro (PSH) under high variable renewables. The study was majority funded by DOE’s Office of Energy Efficiency and Renewable Energy (EERE) through a program managed by EERE’s Water Power Technologies Office. The project team for the study consists of three organizations – GE Research, GE Energy Consulting, and GE Renewables.

13 HYDRO ENERGY↗
NASA NTRS2023

Fluid Inclusions in Extraterrestrial Samples: Failures, Successes, Possibilities, and A Note of Caution

Over the past half century the search for life in the solar system and beyond has become a major research focus, with much effort devoted to finding evidence for liquid H2O and reduced carbon-bearing (organic) species in extraterrestrial samples. The most direct and convincing evidence for the presence of water and organic molecules is provided by fluid inclusions (FI)trapped in minerals that formed on the parent bodies. Beginning in the 1970s, reports of FI in extraterrestrial samples generated much enthusiasm within the planetary sciences community. However, many of the reported FI were determined to be artifacts of sample preparation, or incomplete characterization of features that appear to be FI, or were inconsistent with the inferred PT history of the meteorite sample. An early report of aqueous (and hydrocarbon-bearing) FI in stony meteorites and the subsequent follow-up study that showed that most or all of the “FI” contained water used during cutting and polishing of the samples led to a general unwillingness to believe later reports of FI in meteorites. One of the first confirmed occurrences of extraterrestrial aqueous (liquid) fluid inclusions in a meteorite was reported by Zolensky et al. (1999; Science), who described aqueous inclusions in halite in the Monahans and later the Zag meteorites. These meteorite falls were collected shortly after landing on earth and were prepared without using water or other fluids that could introduce artifacts. The oxygen and hydrogen isotopic composition of water in FI in these same samples was later measured, showing that the fluids represent various degrees of water-rock interaction on the parent body .In more recent years, careful studies of FI trapped in extraterrestrial samples combining synchrotron X-ray computed tomography to locate FI in samples followed by cryo-TOF-SIMS analysis of the FI have identified the presence of molecular fragments suggesting the presence of H2O and various organic molecules in the fluids. Challenges associated with studying FI in extraterrestrial samples include the limited abundance of potential host phases for FI, such as carbonates and phosphates, the often poor optical quality of the host phases, and the small size of the FI, with few as large as 5 microns and most less than 1-2 microns in maximum dimension

Robert Bodnar↗
DOE OSTI2024

Chapter 5: Major Biological Innovations in the History of Life on Earth

All organisms living on Earth descended from a single, common ancestral population of cells, known as LUCA—the last universal common ancestor. Since its emergence, the diversity and complexity of life have increased dramatically. Here this chapter focuses on four key biological innovations throughout Earth's history that had a significant impact on the expansion of phylogenetic diversity, organismal complexity, and ecospace habitation. First is the emergence of the last universal common ancestor, LUCA, which laid the foundation for all life-forms on Earth. Second is the evolution of oxygenic photosynthesis, which resulted in global geochemical and biological transformations. Third is the appearance of a new type of cell—the eukaryotic cell—which led to the origin of a new domain of life and the basis for complex multicellularity. Fourth is the multiple independent origins of multicellularity, resulting in the emergence of a new level of complex individuality. A discussion of these four key events will improve our understanding of the intertwined history of our planet and its inhabitants and better inform the extent to which we can expect life at different degrees of diversity and complexity elsewhere.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Reaction pathways of furfural, furfuryl alcohol and 2-methylfuran on Cu(111) and NiCu bimetallic surfaces

Hydrodeoxygenation (HDO) is an important reaction for converting biomass-derived furfural to value-added 2-methylfuran, which is a promising fuel additive. In this work, the HDO of furfural to produce 2-methylfuran occurred on the NiCu bimetallic surfaces prepared on either Ni(111) or Cu(111). The reaction pathways of furfural were investigated on Cu(111) and Ni/Cu(111) surfaces using density functional theory (DFT) calculations, temperature programmed desorption (TPD) and high resolution electron energy loss spectroscopy (HREELS) experiments. These studies provided mechanistic insights into the effects of bimetallic formation on enhancing the HDO activity. Specifically, furfural weakly adsorbed on Cu(111), while it strongly adsorbed on Ni/Cu(111) through an η 2 (C,O) configuration which led to the HDO of furfural on Ni/Cu(111). Lastly, the ability to dissociate H 2 on Ni/Cu(111) is also an important factor for enhancing the HDO activity over Cu(111).

2-Methylfuran↗
DOE OSTI2021

Tip-Enhanced Raman Scattering on Both Sides of the Schrödinger Equation

We report historically, molecular spectroscopists have focused their attention to the right-hand side of the Schrödinger equation. Our major goal had and still has to do with determining a (bio)molecular system’s Hamiltonian operator. From a theoretical spectroscopist’s perspective, this entails varying the parameters of a model Hamiltonian until the predicted observables agree with their experimental analogues. In this context, less emphasis has been put on the left-hand side of the equation, where the interplay between a system and its immediate local environment is described. The latter is particularly meaningful and informative in modern applications of optical microscopy and spectroscopy that take advantage of surface plasmons to enhance molecular scattering cross-sections and to increase the attainable spatial resolution that is classically limited by diffraction. Indeed, the manipulation of light near the apex of a metallic nanotip has enabled single molecule detection, identification, and imaging. The distinct advantages of the so-called tip-enhanced optical nanospectroscopy/nanoimaging approaches are self-evident: ultrahigh spatial resolution (nanometer or better) and ultimate sensitivity (down to yoctomolar) are both attainable, all while retaining the ability to chemically fingerprint one molecule at a time (e.g., through Raman scattering). An equally interesting aspect of the same approach stems from using the properties of a single molecule to characterize the local environment in which it resides. This concept of single molecule spectroscopy on the left-hand side of the Schrödinger equation is certainly not novel and has been discussed in pioneering single molecule studies that ultimately led to a Nobel prize in chemistry. That said, local environment mapping through ultrasensitive optical spectroscopy acquires a unique flavor when executed using tip-enhanced Raman scattering (TERS). This is the subject of this Account.

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

Combining High-Throughput Experiments and Active Learning to Characterize Deep Eutectic Solvents

The high tunability of deep eutectic solvents (DESs) stems from the ease of changing their precursors and relative compositions. However, measuring the physicochemical properties across large composition and temperature ranges, necessary to properly design target-specific DESs, is tedious and error-prone and represents a bottleneck in the advancement and scalability of DES-based applications. As such, active learning (AL) methodologies based on Gaussian processes (GPs) were developed in this work to minimize the experimental effort necessary to characterize DESs. Owing to its importance for large-scale applications, the reduction of DES viscosity through the addition of a low-molecular-weight solvent was explored as a case study. A high-throughput experimental screening was initially performed on nine different ternary DESs. Then, GPs were successfully trained to predict DES viscosity from its composition and temperature, showcasing the ability of these stochastic, nonparametric models to accurately describe the physicochemical properties of complex mixtures. Finally, the ability of GPs to provide estimates of their own uncertainty was leveraged through an AL framework to minimize the number of data points necessary to obtain accurate viscosity modes. This led to a significant reduction in data requirements, with many systems requiring only five independent viscosity data points to be properly described.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Characteristics of Hot Water Extracts from the Bark of Cultivated Willow ( Salix sp.)

Willow bark is a rich source of heterogeneous polyphenolic compounds and a potential feedstock for biorefinery processes aiming at chemicals and fiber production. Here, mild hot water treatment of willow hybrid Karin was studied to find a practical means of isolating its non-cell-wall components for their utilization in a willow biorefinery proposed to aid valorization of the willow biomass. A short aqueous treatment of the bark at 80 °C liberated the extract in >20% yield under unpressurized conditions. The extract was characterized using mainly gas chromatography-mass spectrometry and one- and two-dimensional NMR techniques. Authentic analytes were applied to confirm the identification and quantification of the main components that were picein, (+)-catechin, triandrin, glucose, and fructose. Fructose was converted into 5-hydroxymethylfurfural in an acidic treatment which led to its condensation with the phenolic components and formation of a recalcitrant precipitate that should be avoided.

(+)-Catechin↗
DOE OSTI2012

Effect of Ionic Liquid Treatment on the Structures of Lignins in Solutions: Molecular Subunits Released from Lignin

The solution structures of three types of isolated lignin—organosolv (OS), Kraft (K), and low sulfonate (LS)—before and after treatment with 1-ethyl-3-methylimidazolium acetate were studied using small-angle neutron scattering (SANS) and dynamic light scattering (DLS) over a concentration range of 0.3–2.4 wt %. The results indicate that each of these lignins is comprised of aggregates of well-defined basal subunits, the shapes and sizes of which, in D 2 O and DMSO-d 6 , are revealed using these techniques. LS lignin contains a substantial amount of nanometer-scale individual subunits. In aqueous solution these subunits have a well-defined elongated shape described well by ellipsoidal and cylindrical models. At low concentration the subunits are highly expanded in alkaline solution, and the effect is screened with increasing concentration. OS lignin dissolved in DMSO was found to consist of a narrow distribution of aggregates with average radius 200 ± 30 nm. K lignin in DMSO consists of aggregates with a very broad size distribution. In conclusion, after ionic liquid (IL) treatment, LS lignin subunits in alkaline solution maintained the elongated shape but were reduced in size. IL treatment of OS and K lignins led to the release of nanometer-scale subunits with well-defined size and shape.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Continuous liquid-phase synthesis of nickel phosphide nanoparticles in a helically coiled tube reactor

The continuous liquid phase synthesis of nickel phosphide (Ni 2 P) nanoparticles was studied in a helically coiled tube (HCT) reactor both in single-phase and two-phase slug flows. The reactants were nickel acetylacetonate and tri-n-octylphosphine (TOP) in a 1-octadecane solvent. For the single-phase mode, various parameters such as reaction temperature, residence time, TOP concentration, and P/Ni ratio were studied. It was found that lower temperatures of 320 and 340 °C resulted in the formation of mixed Ni 12 P 5 and Ni 2 P phases, while a higher temperature of 360 °C gave mostly Ni 2 P, with particle sizes increasing from 28 to 42 nm. Upon varying the contact time between 88 and 340 s at 360 °C, a likely sequence of reaction involved an amorphous phase that was transformed in parallel to Ni, Ni 12 P 5 , and Ni 2 P. When the flow in the HCT was changed to a two-phase slug flow by using N 2 to split the continuous liquid phase into small liquid columns, the product was nearly 100% Ni 2 P and the particle size was as small as 3–4 nm. This was attributed to the enhanced mass transfer in the small liquid columns of the slug flow that led to higher reaction rates. Finally, it is highlighted that the HCT operated in a slug flow is an efficient and continuous method for the fabrication of nanoparticles.

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

Steam-created grain boundaries for methane C–H activation in palladium catalysts

Defects may display high reactivity because the specific arrangement of atoms differs from crystalline surfaces. We demonstrate that high-temperature steam pretreatment of palladium catalysts provides a 12-fold increase in the mass-specific reaction rate for carbon-hydrogen (C–H) activation in methane oxidation compared with conventional pretreatments. Through a combination of experimental and theoretical methods, we demonstrate that an increase in the grain boundary density through crystal twinning is achieved during the steam pretreatment and oxidation and is responsible for the increased reactivity. The grain boundaries are highly stable during reaction and show specific rates at least two orders of magnitude higher than other sites on the palladium on alumina (Pd/Al 2 O 3 ) catalysts. Theoretical calculations show that strain introduced by the defective structure can enhance C–H bond activation. Introduction of grain boundaries through laser ablation led to further rate increases.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

A review of iron and cobalt porphyrins, phthalocyanines, and related complexes for electrochemical and photochemical reduction of carbon dioxide

This review summarizes research on the electrochemical and photochemical reduction of CO₂ using a variety of iron and cobalt porphyrins, phthalocyanines, and related complexes. Metalloporphyrins and metallophthalocyanines are visible light absorbers with extremely large extinction coefficients. However, yields of photochemically-generated active catalysts for CO₂ reduction are typically low owing to the requirement of a second photoinduced electron. This requirement is not relevant to the case of electrochemical CO₂ reduction. Recent progress on efficient and stable electrochemical systems includes the use of FeTPP catalysts that have prepositioned phenyl OH groups in their second coordination spheres. This has led to remarkable progress in carrying out coupled proton-electron transfer reactions for CO₂ reduction. Such ground-breaking research has to be continued in order to produce renewable fuels in an economically feasible manner.

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

Advanced Energy Storage for Extreme Conditions (AESTEC) (Abbreviated Final Report)

This project developed a new capability for designing and fabricating energy storage devices that function in extreme conditions detrimental to conventional devices (e.g. temperature, mechanical stress, etc.). This new toolset tackled critical phenomenological challenges which led to materials and designs that enable high performance energy storage in conditions relevant to national security missions and the broader energy storage community.

25 ENERGY STORAGE↗