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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 541 records · Page 30
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Streamlined Approach for Environmental Restoration (SAFER) Plan for Corrective Action Unit 114: Area 25 EMAD Facility Nevada National Security Site, Nevada

This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the actions needed to achieve closure for Corrective Action Unit (CAU) 114, Area 25 EMAD Facility, identified in the Federal Facility Agreement and Consent Order (FFACO). CAU 114 comprises the following corrective action sites (CASs) located in Area 25 of the Nevada National Security Site: • 25-41-03, EMAD Facility (Building 3900) • 25-99-23, Manned Control Car (MCC) and Engine Installation Vehicle (EIV) • 25-33-05, Building 3901, Engine Transport System Maintenance Building (Train Shed) This plan provides the methodology for field activities needed to gather the necessary information for closing CAU 114. There is sufficient information and process knowledge from historical documentation and investigations of similar sites regarding the expected nature and extent of potential contaminants to recommend closure of CAU 114 using the SAFER process. Additional information will be obtained by conducting a field investigation before selecting the appropriate corrective actions for CAU 114. It is anticipated that the results of the field investigation and implementation of corrective actions will support a defensible recommendation that no further corrective action is necessary. The purpose of the corrective action investigation will be to document and verify the adequacy of existing information; to affirm the decision for either clean closure, closure in place, or no further action; and to provide sufficient data to implement the corrective action. The actual corrective action selected will be based on characterization activities implemented under this SAFER Plan. If specific conditions or findings fall outside the bounds of the conceptual site model, such as an unanticipated release, the Nevada Division of Environmental Protection (NDEP) will be consulted to determine the path forward before proceeding. Upon completion of SAFER activities, a closure report (CR) will be prepared and submitted to NDEP for review and approval. The schedule for completion of the CR will be established in consultation with NDEP.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Streamlined Approach for Environmental Restoration (SAFER) Plan for Corrective Action Unit 114: Area 25 EMAD Facility Nevada National Security Site, Nevada, (Rev.0, with ROTC 1)

This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the actions needed to achieve closure for Corrective Action Unit (CAU) 114, Area 25 EMAD Facility, identified in the Federal Facility Agreement and Consent Order (FFACO). CAU 114 comprises the following corrective action sites (CASs) located in Area 25 of the Nevada National Security Site (formerly, the Nevada Test Site): 25-41-03, EMAD Facility; 25-99-23, Manned Control Car (MCC) and Engine Installation Vehicle (EIV); and 25-33-05, Building 3901, Engine Transport System Maintenance Building. This plan provides the methodology for field activities needed to gather the necessary information for closing CAU 114. There is sufficient information and process knowledge from historical documentation and investigations of similar sites regarding the expected nature and extent of potential contaminants to recommend closure of CAU 114 using the SAFER process. Additional information will be obtained by conducting a field investigation before selecting the appropriate corrective actions for CAU 114. It is anticipated that the results of the field investigation and implementation of corrective actions will support a defensible recommendation that no further corrective action is necessary. The purpose of the corrective action investigation will be to document and verify the adequacy of existing information; to affirm the decision for either clean closure, closure in place, or no further action; and to provide sufficient data to implement the corrective action. The actual corrective action selected will be based on characterization activities implemented under this SAFER Plan. If specific conditions or findings fall outside the bounds of the SAFER Plan, the Nevada Division of Environmental Protection (NDEP) will be consulted to determine the path forward before proceeding. Upon completion of SAFER activities, a closure report will be prepared and submitted to NDEP for review and approval. The schedule for completion of the closure report will be established at the FFACO annual meeting.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Streamlined Approach for Environmental Restoration (SAFER) Plan for Corrective Action Unit 572: Test Cell C Ancillary Building and Structures - Nevada National Security Site, Nevada with ROTC 1

This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the actions needed to achieve closure for Corrective Action Unit (CAU) 572, Test Cell C Ancillary Building and Structures, identified in the Federal Facility Agreement and Consent Order (FFACO). CAU 572 comprises the following corrective action sites (CASs) located in Area 25 of the Nevada National Security Site: CAS 25-33-01, Building 3220, Equipment Building; CAS 25-33-02, Building 3230, Motor Drive Building; CAS 25-33-03, Building 3231, Pump House; CAS 25-33-04, Building 3232, Cryogenic Evaluation Lab; CAS 25-99-22, Ancillary Facilities. This plan provides the methodology for field activities needed to gather the necessary information for closing CAU 572. There is sufficient information and process knowledge from historical documentation and investigations of similar sites regarding the expected nature and extent of potential contaminants to recommend closure of CAU 572 using the SAFER process. Additional information will be obtained by conducting a field investigation before selecting the appropriate corrective action. It is anticipated that the results of the field investigation and implementation of corrective actions will support a defensible recommendation that no further corrective action is necessary. The purpose of the corrective action investigation (CAI) will be to document and verify the adequacy of existing information; to affirm the decision for either clean closure, closure in place, or no further action; and to provide sufficient data to implement the corrective action. The actual corrective action selected will be based on characterization activities implemented under this SAFER Plan. If it is determined that complete clean closure cannot be accomplished during the CAI, then a hold point will have been reached and the Nevada Division of Environmental Protection (NDEP) will be consulted to determine whether the remaining contamination will be closed under the alternative corrective action of closure in place. This will be presented in a closure report that will be prepared and submitted to NDEP for review and approval.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Computational quantum chemistry of metal–organic frameworks

Metal–organic frameworks (MOFs) have premium exceptional properties for a variety of functions, such as gas separation and storage and catalysis. The large variety of possible inorganometallic nodes and organic linkers provide an almost unlimited number of combinations for assembling MOFs, which makes the experimental characterization and examination of all potentially useful combinations practically impossible. Furthermore, experimental studies of MOFs typically fall short in uncovering crucial details regarding their mechanisms of action or the molecular details responsible for their functional properties, such as the nature of adsorbate binding or the structures of transition states. Computational modeling has, therefore, become an efficient and important tool for strategizing the functionalization of MOFs and explicating the mechanisms of their functions. Furthermore, we review the computational methodologies used for computational studies of MOFs, especially Kohn–Sham density functional theory and combined quantum mechanical and molecular mechanical methods for calculating their structural, electronic, and magnetic properties, as well as for understanding the mechanisms of MOFs' applications to magetic devices, thermal conduction, gas adsorption, separation, storage, and sensing, thermal catalysis, photocatalysis, and electrocatalysis.

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

Advancing stem cell technologies for conservation of wildlife biodiversity

ABSTRACT Wildlife biodiversity is essential for healthy, resilient and sustainable ecosystems. For biologists, this diversity also represents a treasure trove of genetic, molecular and developmental mechanisms that deepen our understanding of the origins and rules of life. However, the rapid decline in biodiversity reported recently foreshadows a potentially catastrophic collapse of many important ecosystems and the associated irreversible loss of many forms of life on our planet. Immediate action by conservationists of all stripes is required to avert this disaster. In this Spotlight, we draw together insights and proposals discussed at a recent workshop hosted by Revive & Restore, which gathered experts to discuss how stem cell technologies can support traditional conservation techniques and help protect animal biodiversity. We discuss reprogramming, in vitro gametogenesis, disease modelling and embryo modelling, and we highlight the prospects for leveraging stem cell technologies beyond mammalian species.

Developmental Biology↗
NASA NTRS1972

Population inversion calculations using near resonant charge exchange as a pumping mechanism

Near resonance charge exchange between ions of a large ionization potential gas such as helium or neon and vapors of metals such as zinc, cadmium, selenium, or tellurium has produced laser action in the metal ion gas. The possibility of obtaining population inversions in near resonant charge exchange systems (Xe-Ca, Xe-Mg, Xe-Sr, Xe-Ba, Ar-Mg, N-Ca) was investigated. The analysis is an initial value problem that utilizes rate equations for the densities of relevant levels of the laser gas (Ca, Ba, Mg, or Sr) and an electron energy equation. Electron excitation rates are calculated using the Bohr-Thomson approximation for the cross section. Approximations to experimental values of the electron ionization cross section and the ion-atom charge exchange cross section are used. Preliminary results have been obtained for the Ca-Xe system and show that it is possible to obtain gains greater than 10 to the 14th power/m with inversion times up to 8x10 to the minus 7th power second. A possible charge exchange laser system using a MPD arc plasma accelerator is also described.

Chubb, D. L.↗
NASA NTRS1973

Study of V/STOL aircraft implementation. Volume 1: Summary

A high density short haul air market which by 1980 is large enough to support the introduction of an independent short haul air transportation system is discussed. This system will complement the existing air transportation system and will provide relief of noise and congestion problems at conventional airports. The study has found that new aircraft, exploiting V/STOL and quiet engine technology, can be available for implementing these new services, and they can operate from existing reliever and general aviation airports. The study has also found that the major funding requirements for implementing new short haul services could be borne by private capital, and that the government funding requirement would be minimal and/or recovered through the airline ticket tax. In addition, a suitable new short haul aircraft would have a market potential for $3.5 billion in foreign sales. The long lead times needed for aircraft and engine technology development will require timely actions by federal agencies.

Portenier, W. J.↗
NASA NTRS1983

Proceedings of a Workshop on Applications of Tethers in Space, Executive Summary

The objectives were to identify potential applications for tethers in space; develop a first order assessment of the feasibility and benefits of tether applications; recommend future actions necessary to enable tether applications, including required technology advancements; and stimulate industry and government planners to consider the unique properties of tethers in designs for future missions.

Source record↗
NASA NTRS1985

Role of Glucocorticoids in the Response to Unloading of Muscle Protein and Amino Acid Metabolism

Intact control (weight bearing) and suspended rats gained weight at a similar rate during a 6 day period. Adrenaectomized (adx) weight bearing rats gained less weight during this period while adrenalectomized suspended rats showed no significant weight gain. Cortisol treatment of both of these groups of animals caused a loss of body weight. Results from these studies show several important findings: (1) Metabolic changes in the extensor digitorum longus muscle of suspended rats are due primarily to increased circulating gluccorticoids; (2) Metabolic changes in the soleus due to higher steroid levels are probably potentiated by greater numbers of receptors; and (3) Not all metabolic responses in the unloaded soleus muscle are due to direct action of elevated glucocorticoids or increased sensitivity to these hormones.

Tischler, M. E.↗
NASA NTRS1993

Comparison of dayside current layers in Venus' ionosphere and earth's equatorial electrojet

The major physical aspects of the equatorial electrojet of Earth and the dayside ionospheric current layers of Venus are compared, viz., the electric current intensity and total current, roles of electric field, pressure and gravity, diffusion time scales, and the Bernouille effect. The largest potential differences, of the order of 10 volts, horizontally across the dayside ionosphere of Venus, have important implications for possible dynamo action in the Venus ionosphere and the application of an electric field from the lower atmosphere or from the solar wind. An upper limit to the horizontal scale of vertical magnetic fields in the Venus ionosphere is estimated thereby for the first time. New upper limits on the velocity in, and thickness of, a possible S layer at Venus are presented. If an S layer exists, it is only for extreme conditions of the solar wind. A mechanism for formation of magnetic ropes in the Venus ionosphere is also proposed.

Cole, Keith D.↗
NASA NTRS2004

Miniature Loop Heat Pipe (MLHP) Thermal Management System

The MLHP Thermal Management System consists of a loop heat pipe (LHP) with multiple evaporators and condensers, thermal electrical coolers, and deployable radiators coated with variable emittance coatings (VECs). All components are miniaturized. It retains all the performance characteristics of state-of-the-art LHPs and offers additional advantages to enhance the functionality, versatility, and reliability of the system, including flexible locations of instruments and radiators, a single interface temperature for multiple instruments, cooling the on instruments and warming the off instruments simultaneously, improving. start-up success, maintaining a constant LHP operating temperature over a wide range of instrument powers, effecting automatic thermal switching and thermal diode actions, and reducing supplemental heater powers. It can fully achieve low mass, low power and compactness necessary for future small spacecraft. Potential applications of the MLHP thermal technology for future missions include: 1) Magnetospheric Constellation; 2) Solar Sentinels; 3) Mars Science Laboratory; 4) Mars Scouts; 5) Mars Telecom Orbiter; 6) Space Interferometry Mission; 7) Laser Interferometer Space Antenna; 8) Jupiter Icy Moon Orbiter; 9) Terrestrial Planet Finder; 10) Single Aperture Far-Infrared Observatory, and 11) Exploration Missions. The MLHP Thermal Management System combines the operating features of a variable conductance heat pipe, a thermal switch, a thermal diode, and a state-of-the-art LHP into a single integrated thermal system. It offers many advantages over conventional thermal control techniques, and can be a technology enabler for future space missions. Successful flight validation will bring the benefits of MLHP technology to the small satellite arena and will have cross-cutting applications to both Space Science and Earth Science Enterprises.

Ku, Jentung↗
NASA NTRS2017

Geomagnetically Induced Currents: Science, Engineering, and Applications Readiness

This paper is the primary deliverable of the very first NASA Living With a Star Institute Working Group, Geomagnetically Induced Currents (GIC) Working Group. The paper provides a broad overview of the current status and future challenges pertaining to the science, engineering, and applications of the GIC problem. Science is understood here as the basic space and Earth sciences research that allows improved understanding and physics-based modeling of the physical processes behind GIC. Engineering, in turn, is understood here as the ''impact'' aspect of GIC. Applications are understood as the models, tools, and activities that can provide actionable information to entities such as power systems operators for mitigating the effects of GIC and government agencies for managing any potential consequences from GIC impact to critical infrastructure. Applications can be considered the ultimate goal of our GIC work. In assessing the status of the field, we quantify the readiness of various applications in the mitigation context. We use the Applications Readiness Level (ARL) concept to carry out the quantification.

Geomagnetically induced currents↗
NASA NTRS2017

A Fuzzy Logic Approach for Separation Assurance and Collision Avoidance for Unmanned Aerial Systems

In the coming years, operations in low altitude airspace will vastly increase as the capabilities and applications of small Unmanned Aerial Systems (sUAS) continue to multiply. Therefore, solutions to managing sUAS in highly congested airspace must be explored. In this study, a Fuzzy Logic based approach was used to help mitigate the risk of collisions between aircraft using separation assurance and collision avoidance techniques. The system was evaluated for its effectiveness to mitigate the risk of mid-air collisions between aircraft. This system utilizes only current state information and can resolve potential conflicts without knowledge of intruder intent. The avoidance logic was verified using formal methods and shown to select the correct action in all instances. Additionally, the Fuzzy Logic Controllers were shown to always turn the vehicles in the correct direction. Numerical testing demonstrated that the avoidance system was able to prevent a mid-air collision between two sUAS in all tested cases. Simulations were also performed in a three-dimensional environment with a heterogenous fleet of sUAS performing a variety of realistic missions. Simulations showed that the system was 99.98 effective at preventing mid-air collisions when separation assurance was disabled (unmitigated case) and 100 effective when enabled (mitigated case).

Verification & Validation of a Fuzzy Logic Control↗
DOE OSTI2020

Quantitative intramolecular fission in oligoacenes, materials, and methods of use thereof

The present invention provides soluble, stable singlet fission (SF) compounds, compositions, materials, methods of their use, and methods for their preparation that provide efficient intramolecular singlet fission (iSF) and multiple excitons. The SF compound may be a dimer, an oligomer, or a polymer of polyoligoacenes, where for example, the compound achieves a triplet yield reaching about 200% per absorbed photon. In this system, SF does not depend on intermolecular inter-actions. Instead, SF is an intrinsic property of the molecule and therefore occurs independent of intermolecular interactions. Singlet fission has the potential to significantly improve the photocurrent in single junction solar cells and thus raise the Shockley-Queisser power conversion efficiency limit from about 33% to about 46% or greater. Quantitative SF yield at room temperature has only been observed in crystalline solids or aggregates of higher acenes.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Decarbonizing Hydrogen Production: Assessing A Net-Negative Pathway

Hydrogen is gaining prominence as a key factor in the world's transition to a cleaner energy future. The International Energy Agency (IEA)'s Global Hydrogen Review 2023 reports that the number of low-emission hydrogen production projects is increasing rapidly. The potential for growth in new applications such as heavy industry, transportation, and power generation is significant. The IEA urges more decisive action to spur demand for low-emission hydrogen to achieve climate goals. While hydrogen is produced through various industrial methods, each with its own advantages and disadvantages, low-carbon hydrogen is critical for mitigating climate change and is incentivized by the Clean Hydrogen Production Tax Credit (45V). To this end, we have evaluated a commercial technology that can produce low- or negative-carbon hydrogen via ethanol catalytic oxidative reforming. This study assessed life cycle greenhouse gas emissions (carbon intensity or CI) associated with the hydrogen production technology. A total of 24 scenarios were evaluated, encompassing (a) Gen1 versus Gen2 ethanol inputs, (b) carbon capture and sequestration (CCS) of upstream fermentation CO2, and (c) oxygen sourcing via air separation unit (ASU) versus purchased or on-site production of oxygen as a byproduct of hydrogen electrolysis with a proton exchange membrane (PEM). Key findings include that the base case CI for hydrogen production using Gen2 ethanol from corn stover is lower than Gen1 dry mill corn ethanol. The study also points out that the CI for hydrogen production using PEM-O2 is lower than that using ASU-O2, whether the PEM-O2 is produced on-site or off-site (importing). When sourcing oxygen from on-site PEM-O2, the Gen1 and Gen2 ethanol-derived hydrogen exhibit favorable net-negative CI values for all evaluated scenarios, especially if the upstream ethanol CCS is included. As a reference, the 45V regulatory threshold for generating clean hydrogen tax credits is a CI below 0.45 kg CO2e/kg hydrogen.

BIOMASS FUELS,HYDROGEN↗
NASA NTRS2006

Biology-inspired Architecture for Situation Management

Situation Management is a rapidly developing science combining new techniques for data collection with advanced methods of data fusion to facilitate the process leading to correct decisions prescribing action. Current research focuses on reducing increasing amounts of diverse data to knowledge used by decision makers and on reducing time between observations, decisions and actions. No new technology is more promising for increasing the diversity and fidelity of observations than sensor networks. However, current research on sensor networks concentrates on a centralized network architecture. We believe this trend will not realize the full potential of situation management. We propose a new architecture modeled after biological ecosystems where motes are autonomous and intelligent, yet cooperate with local neighborhoods. Providing a layered approach, they sense and act independently when possible, and cooperate with neighborhoods when necessary. The combination of their local actions results in global effects. While situation management research is currently dominated by military applications, advances envisioned for industrial and business applications have similar requirements. NASA has requirements for intelligent and autonomous systems in future missions that can benefit from advances in situation management. We describe requirements for the Integrated Vehicle Health Management program where our biology-inspired architecture provides a layered approach and decisions can be made at the proper level to improve safety, reduce costs, and improve efficiency in making diagnostic and prognostic assessments of the structural integrity, aerodynamic characteristics, and operation of aircraft.

Jones, Kennie H.↗
NASA NTRS1996

Excess chemical potential of small solutes across water--membrane and water--hexane interfaces

The excess chemical potentials of five small, structurally related solutes, CH4, CH3F, CH2F2, CHF3, and CF4, across the water-glycerol 1-monooleate bilayer and water-hexane interfaces were calculated at 300, 310, and 340 K using the particle insertion method. The excess chemical potentials of nonpolar molecules (CH4 and CF4) decrease monotonically or nearly monotonically from water to a nonpolar phase. In contrast, for molecules that possess permanent dipole moments (CH3F, CH2F, and CHF3), the excess chemical potentials exhibit an interfacial minimum that arises from superposition of two monotonically and oppositely changing contributions: electrostatic and nonelectrostatic. The nonelectrostatic term, dominated by the reversible work of creating a cavity that accommodates the solute, decreases, whereas the electrostatic term increases across the interface from water to the membrane interior. In water, the dependence of this term on the dipole moment is accurately described by second order perturbation theory. To achieve the same accuracy at the interface, third order terms must also be included. In the interfacial region, the molecular structure of the solvent influences both the excess chemical potential and solute orientations. The excess chemical potential across the interface increases with temperature, but this effect is rather small. Our analysis indicates that a broad range of small, moderately polar molecules should be surface active at the water-membrane and water-oil interfaces. The biological and medical significance of this result, especially in relation to the mechanism of anesthetic action, is discussed.

NASA Center ARC↗
DOE OSTI2022

Nuclear decisionmaking, complexity and emerging and disruptive technologies: A comprehensive assessment

The complex interactions of emerging and disruptive technologies (EDTs) could significantly impact nuclear decision-making, particular in an escalating regional conventional conflict. Such conflicts may present governments with a range of nuclear decisions: whether to introduce a nuclear dimension to a crisis, whether to cross the nuclear threshold through limited nuclear use, how to respond to a limited nuclear attack, whether to expand the scope and intensity of initial limited attacks, and whether to escalate to an all-out nuclear war. At each decision point, EDTs create potential risks as well as rewards. EDTs are likely to influence the context for nuclear decision-making and the choices between different courses of action. EDTs could impact the context of nuclear decision-making by improving or degrading situational assessment, the ability to deliberate, and the ability to manage one’s nuclear forces. EDTs could influence the choice between nuclear restraint or escalation by affecting the perceived strategic benefits, escalatory risks, and operational requirements associated with different courses of action. Even though particular combinations of EDTs could precipitate nuclear use in some scenarios, they could encourage restraint in others. The impact and relevance of the same combinations of EDTs might be different at various nuclear decision points. The availability of specific combinations of EDTs at different stages of a conflict would also vary because of the attrition and one-time-use nature of some capabilities. In later stages of a conflict, the decision maker’s confidence in different combinations of EDTs would depend on their previous experience in using them. While the interactions of EDTs are likely to bring additional complexity to a nuclear decision-making process, EDTs are also not the only source of complexity. Broader strategic, military, operational, legal, moral, and emotional factors are also likely to play an important role. These factors may dominate decision-making in a range of potential cases.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗