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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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS1994

Safety concerns for first entry operations of orbiting spacecraft

The Space Station Freedom crew will face operational problems unique to the spacecraft environment due to the absence of convection currents and the confined atmosphere within the habitable modules. Airborne contaminants from the materials offgassing or contingency incidents like thermodegradation may accumulate until they reach hazardous concentrations. Flow modeling and experiences from previous space flight missions confirm that caution must be exercised during first-entry operations. A review of the first-entry procedures performed during the Skylab Program will be presented to highlight the necessity for carefully planned operations. Many of the environmental conditions that can be expected on the Space Station are analogous to those which exist in confined storage or work spaces in the industrial setting. Experience with closed-loop environmental operations (e.g., atmospheric control of submarines) have also demonstrated that the buildup of trace contaminant gases could result in conditions that lead to mission termination or loss of crew. Consequently, some first-entry issues for the Station can be addressed by comparing them to familiar techniques developed on Earth. The instruments of the Environmental Health System (EHS) will provide the necessary monitoring capability to protect crew health and safety during the planned first-entry procedures of the MTC phase of the SSF Program. The authors of this paper will describe those procedures and will cite an example of the consequences when proper first-entry procedures are not followed.

Wilson, Steven H.↗
NASA NTRS2006

The Exploration Water Recovery System

The Exploration Water Recovery System is designed towards fulfillment of NASA s Vision for Space Exploration, which will require elevation of existing technologies to higher levels of optimization. This new system, designed for application to the Exploration infrastructure, presents a novel combination of proven air and water purification technologies. The integration of unit operations is modified from that of the current state-of-the-art water recovery system so as to optimize treatment of the various waste water streams, contaminant loads, and flow rates. Optimization is achieved primarily through the removal of volatile organic contaminants from the vapor phase prior to their absorption into the liquid phase. In the current state-of-the-art system, the water vapor in the cabin atmosphere is condensed, and the volatile organic contaminants present in that atmosphere are absorbed into the aqueous phase. Removal of contaminants the5 occurs via catalytic oxidation in the liquid phase. Oxidation kinetics, however, dictate that removal of volatile organic contaminants from the vapor phase can inherently be more efficient than their removal from the aqueous phase. Taking advantage of this efficiency reduces the complexity of the water recovery system. This reduction in system complexity is accompanied by reductions in the weight, volume, power, and resupply requirements of the system. Vapor compression distillation technology is used to treat the urine, condensate, and hygiene waste streams. This contributes to the reduction in resupply, as incorporation of vapor compression distillation technology at this point in the process reduces reliance on the expendable ion exchange and adsorption media used in the current state-of-the-art water recovery system. Other proven technologies that are incorporated into the Exploration Water Recovery System include the Trace Contaminant Control System and the Volatile Removal Assembly.

ORourke, Mary Jane E.↗
DOE OSTI2024

Circular Economy Contributions to Decarbonizing the US Steel Sector

The potential benefits of the circular economy (CE) for decarbonization have recently attracted much attention in the academic and grey literature. The department of energy (DOE) industrial decarbonization roadmap highlight that in addition to the four pillars (energy efficiency, electrification, low-carbon fuels, feedstocks, and energy sources, and carbon capture, utilization, and storage (CCUS)) identified in the roadmap, "scenarios [...] will need to be developed that incorporate materials efficiency and circular economy strategies". Moreover, the roadmap identifies hard-to-abate CO2 emissions across the five industrial subsectors included in the analysis (iron & steel, chemical, food & beverage, refining, and cement manufacturing). Thus, additional options to decarbonize the industrial sector, like the CE, could prove beneficial to address those hard-to-abate emissions. Moreover, they may be less costly, require less R&D or incentives, and be more readily adopted than other strategies such as energy efficiency and CCUS. While the Industrial Decarbonization Roadmap includes some CE strategies (e.g., the increasing market share of steel from electric arc furnaces - which incorporate steel scrap), a deeper dive into what role the CE could play in the United States (US) industrial decarbonization is needed. In this work, we present several industrial decarbonization scenarios that incorporate materials efficiency and circular economy strategies for the iron & steel subsector. The scenarios identify barriers (including technical limits and constraints), opportunities, and R&D needs.Moreover, we estimate the contribution of those scenarios to reducing the industrial sector's CO2 emissions and their potential synergies with the Industrial Decarbonization Roadmap's four pillars. Iron & steel manufacturing was responsible for 90 million tons of industrial CO2 emissions in 2020 - 7% of the industrial sector's total process- related emissions. Besides recycling - which presents technical limitations due to trace contaminants - CE strategies on the demand side could lower iron & steel manufacturing emissions (e.g., the development of lighter products or business models that encourage a more intensive use). This study reviews barriers, opportunities, and trade-offs for 5 material efficiency strategies. Many topics explored in the review call for further research.

barriers↗
DOE OSTI2023

Separation of rare earth element radioisotopes by reverse-phase high-speed counter-current chromatography

Analytical scale purification of rare earth element (REE) radioisotopes is typically accomplished using cation-exchange resins (e.g. AG 50W-X8) and high-performance liquid chromatography (HPLC). Despite the variety of improvements made since the development of this separation process in the 1950s, nearest neighbor separations remain a challenge, as does the issue of irreversible sample adsorption. Herein, we report a study that evaluates the potential of high-speed counter-current chromatography (HSCCC) as an alternative method for purifying REE elements, with specific reference to separations of fission product REE of interest to nuclear forensics. Complementary HSCCC REE separation experiments, one spiked with radiotracer and REE fission product activity, allowed for in depth analysis of resulting fractions from both an elemental (inductively coupled plasma atomic emission spectroscopy, ICP-AES) and radiological (gamma-ray spectrometry, beta counting) purity perspective. The highly reproducible nature of separation profiles generated from HSCCC instruments was leveraged to simplify work-up of samples containing radioisotopes. Subsequent radioanalytical evaluation revealed minimal carryover of Eu into neighboring Sm and Tb fractions (as indicated by presence of 150Eu), and trace contamination of the Tb fraction with Y (as indicated by presence of 91Y). Subtle differences in stationary phase retention across the two columns were reflected in significant variations in decontamination factors of duplicate parallel separations. Furthermore, these differences paired with obtained distribution of radioisotopes provided valuable insights into future improvements. Collectively, this study represents a significant step forward in development of HSCCC technology for task specific REE radioisotope purification.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2021

Structures of two novel crystal forms of Aspergillus oryzae alpha amylase (taka-amylase)

The structures of Aspergillus oryzae α-amylase were determined in a tetragonal crystal, having one molecule as asymmetric unit, and a monoclinic crystal with two molecules as asymmetric unit. Both crystal forms were obtained from trace contaminants of an old commercial lipase preparation. Structures were determined and refined to 1.65 Å and 1.43 Å resolution respectively. The latter crystal has a non-crystallographic (NCS) twofold axis within the asymmetric unit. Glycosylation at Asn197 is evident, and in the tetragonal crystal can be seen to include three, partially disordered sugar residues following the initial N-acetyl glucosamine (NAG). Superposition of the tetragonal crystal model on the α-amylases from Bacillus subtilis (PDB:1BAG), pig pancreas (PDB:3L2L), and barley (PDB:1AMY), show a high degree of coincidence, particularly for the (β/α)8-barrel domains, and especially within the active site. Using this structural agreement between amylases, we extrapolated the binding model of a six residue, limit dextrin found in pig pancreas α-amylase to the A. oryzae enzyme model, which predicts substrate interacting amino acid residues.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2026

Elemental analysis of air-sensitive frozen molten salt samples using an inert transfer chamber for LIBS/LA-ICP-TOF-MS analysis

A novel inert sample transfer system was developed and employed to enable, for the first time, the analysis of air-sensitive salt samples in a two-volume ablation cell using simultaneous laser-induced breakdown spectroscopy (LIBS) and laser ablation (LA)-inductively coupled plasma (ICP)-time-of-flight (TOF)-mass spectrometry (MS) analysis. Molten salts are of growing interest as a medium for advanced nuclear reactors and nuclear fuel reprocessing technologies continue to be developed around their use. However, compositional analysis of molten salt samples can be challenging because of their air-sensitive nature and varying solubilities leading to inaccurate measurements when digested. LA-based analysis provides an alternate method to digestion and can provide rapid elemental information with little sample preparation. In this study, LIBS and LA-ICP-TOF-MS were used to analyze the Ce content in frozen salt samples taken from a series of electrochemical experiments. Calibrations were built for each technique, and the resulting limits of detection for Ce were estimated to be 107 and 58 µg g −1 for LIBS and LA-ICP-TOF-MS, respectively. Test samples from the electrochemical experiments were analyzed using these calibrations. The results matched bulk digestion-based ICP-optical emission spectroscopy values, and daily trends in Ce concentration changes were identified. Additionally, the LIBS and LA-ICP-TOF-MS analysis was demonstrated for identifying microgram per gram levels of components and detecting trace contaminants. The impurities detected by LIBS included Al, Mg, Ca, and Na. The impurities detected by LA-ICP-TOF-MS included W, Ag, Al, Fe, Ni, Mo, Nd, Sm, Th, and U.

Andrews, Hunter B. [Oak Ridge National Laboratory ↗
DOE OSTI2022

Promise of nonthermal plasmas in addressing emerging environmental and health problems: Present and future

Nonthermal atmospheric pressure plasmas transform input electrical energy efficiently into reactive species, charged particles, and photons. This “activated gas” is being investigated as solutions for a range of environmental and health problems facing society today. In this Perspective, we take a cursory look at a few of these societal problems and the reflected role that plasmas may play in charting the pathway to a solution buoyed by supporting research. Here, we survey the plasma-based opportunities in the removal of trace contaminants in water supporting methodologies such as water reuse, which addresses scarcity and pollution, the opportunity posed by plasmas-based chemical depolymerization for plastics recycling, and the application of plasmas for food security, which includes sterilization of foodstuffs and the improvement of crop yield. Finally, we also included a short review on how plasmas may help control disease spread. In each case, the scope of the problem is presented along with the potential plasma-based solution.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2021

Ion-capture electrodialysis using multifunctional adsorptive membranes

Technologies that can efficiently purify nontraditional water sources are needed to meet rising global demand for clean water. Water treatment plants typically require a series of costly separation units to achieve desalination and the removal of toxic trace contaminants such as heavy metals and boron. We report a series of robust, selective, and tunable adsorptive membranes that feature porous aromatic framework nanoparticles embedded within ion exchange polymers and demonstrate their use in an efficient, one-step separation strategy termed ion-capture electrodialysis. This process uses electrodialysis configurations with adsorptive membranes to simultaneously desalinate complex water sources and capture diverse target solutes with negligible capture of competing ions. Our methods are applicable to the development of efficient and selective multifunctional separations that use adsorptive membranes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1970

New method for photoresist stripping

Vacuum dehydration of negatively working photoresist eliminates trace contamination of conventional stripping methods. The semiconductor substrate is coated with photoresist, exposed, developed, cured, and etched, and then placed in a vacuum. Following dehydration, the resist film is removable with ordinary solvents.

Davern, W. E.↗
NASA NTRS1973

Atmosphere control

Atmospheric control studies emphasized the carbon dioxide problem. Trace contaminants are removed by solid adsorbents and by catalytic oxidation. Humidity control and storage systems for atmospheric constituents are briefly summarized.

Jones, W. L.↗
NASA NTRS1974

Design and performance of Skylab thermal/environmental control system

The function of the thermal/environmental control systems was to provide a comfortable thermal environment for the crew, to cool electronic components, to supply a controlled oxygen/nitrogen atmosphere, and to remove moisture, carbon dioxide, odors, and trace contaminants from the atmosphere. A separate refrigeration system was used to chill and freeze food and biomedical samples and to provide cold water for drinking. This paper describes system design and compares in-flight performance to preflight predictions. A discussion of in-flight anomalies and corrective actions is also included.

Hopson, G. D.↗
NASA NTRS1975

Cost analysis of life sciences experiments and subsystems

Cost estimates for experiments and subsystems flown in the Spacelab were established. Ten experiments were cost analyzed. Estimated cost varied from $650,000 for the hardware development of the SPE water electrolysis experiment to $78,500,000 for the development and operation of a representative life sciences laboratory program. The cost of subsystems for thermal, atmospheric and trace contaminants control of the Spacelab internal atmosphere was also estimated. Subsystem cost estimates were based on the utilization of existing components developed in previous space programs whenever necessary.

Yakut, M. M.↗
NASA NTRS1975

The role of toxicology in the Apollo space program

Some of the major considerations are presented which governed the formation and application of the toxicology program employed in support of the Apollo program. The overriding concern of the program was the safety of crews exposed to trace contaminant gases for extended periods of time. The materials screening program employed, in conjunction with a well designed spacecraft environmental control system, helped to attain the goals set forth for the Apollo program. The knowledge gained from working with the toxicity problems and the identification of compounds in the space cabin atmosphere are of importance for continued efforts in manned space flight. Tabular data of spacecraft contaminants are presented.

Wayland J. Rippstein, Jr↗
NASA NTRS1976

Vacuum ultraviolet spectra of uranium hexafluoride/argon mixtures

The transmission properties of room temperature helium at pressures up to 20 atmospheres were determined in the wavelength range from 80 to 300 nm. Similarly, the transmission properties of uranium hexafluoride at 393 K (pressures less than 1.0 mm) were determined in the wavelength range from 80 to about 120 nm. The results show that high pressure helium is sufficiently transparent in the vacuum ultraviolet region (provided trace contaminants are removed) to be utilized as a transparent purge gas in future fissioning gaseous uranium plasma reactor experiments. Absorption cross sections for uranium hexafluoride were calculated from the data between 80 and 120 nm and were of the order of 10 to the -17 power sq cm.

Krascella, N. L.↗
NASA NTRS1979

Corona-discharge air-purification system

Plasma reaction chamber removes trace contaminants from spacecraft, submarines, and other closed environments by oxidizing contaminants to produce carbon dioxide and water. Contaminants are alcohols, esters, hydrogen sulfide, and ammonia. Others are lubricant solvents such as Freons, aromatics, and Ketones. Contaminants are removed from chamber by scrubber.

Wydeven, T. J.↗