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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
NASA NTRS2000

Large-Area Atomic Oxygen Facility Used to Clean Fire-Damaged Artwork

In addition to completely destroying artwork, fires in museums and public buildings can soil a displayed artwork with so much accumulated soot that it can no longer be used for study or be enjoyed by the public. In situations where the surface has not undergone extensive charring or melting, restoration can be attempted. However, soot deposits can be very difficult to remove from some types of painted surfaces, particularly when the paint is fragile or flaking or when the top surface of the paint binder has been damaged. Restoration typically involves the use of organic solvents to clean the surface, but these solvents may cause the paint layers to swell or leach out. Also, immersion of the surface or swabbing during solvent cleaning may move or remove pigment through mechanical contact, especially if the fire damage extends into the paint binder. A noncontact technique of removing organic deposits from surfaces was developed out of NASA research on the effects of oxygen atoms on various materials. Atomic oxygen is present in the atmosphere surrounding the Earth at the altitudes where satellites typically orbit. It can react chemically with surface coatings or deposits that contain carbon. In the reaction, the carbon is converted to carbon monoxide and some carbon dioxide. Water vapor is also a byproduct of the reaction if the surface contains carbon-hydrogen bonds. To study this reaction, NASA developed Earth-based facilities to produce atomic oxygen for material exposure and testing. A vacuum facility designed and built by the Electro-Physics Branch of the NASA Glenn Research Center at Lewis Field to provide atomic oxygen over a large area for studying reactions in low Earth orbit has been used to successfully clean several full-size paintings. (This facility can accommodate paintings up to 1.5 by 2.1 m. The atomic oxygen plasma is produced between two large parallel aluminum plates using a radiofrequency power source operating at roughly 400 W. Atomic oxygen is generated uniformly over this area at an operating pressure of 1 to 5 mtorr.

Rutledge, Sharon K.↗
NASA NTRS2008

Cleaning Genesis Solar Wind Collectors with Ultrapure Water: Residual Contaminant Particle Analysis

Additional experience has been gained in removing contaminant particles from the surface of Genesis solar wind collectors fragments by using megasonically activated ultrapure water (UPW)[1]. The curatorial facility has cleaned six of the eight array collector material types to date: silicon (Si), sapphire (SAP), silicon-on-sapphire (SOS), diamond-like carbon-on-silicon (DOS), gold-on-sapphire (AuOS), and germanium (Ge). Here we make estimates of cleaning effectiveness using image analysis of particle size distributions and an SEM/EDS reconnaissance of particle chemistry on the surface of UPW-cleaned silicon fragments (Fig. 1). Other particle removal techniques are reported by [2] and initial assessment of molecular film removal is reported by [3].

Allton, J. H.↗
NASA NTRS2007

Plants Clean Air and Water for Indoor Environments

Wolverton Environmental Services Inc., founded by longtime government environmental scientist B.C. "Bill" Wolverton, is an environmental consulting firm that gives customers access to the results of his decades of cutting-edge bioremediation research. Findings about how to use plants to improve indoor air quality have been published in dozens of NASA technical papers and in the book, "How to Grow Fresh Air: 50 Houseplants That Purify Your Home or Office." The book has now been translated into 12 languages and has been on the shelves of bookstores for nearly 10 years. A companion book, "Growing Clean Water: Nature's Solution to Water Pollution," explains how plants can clean waste water. Other discoveries include that the more air that is allowed to circulate through the roots of the plants, the more effective they are at cleaning polluted air; and that plants play a psychological role in welfare in that people recover from illness faster in the presence of plants. Wolverton Environmental is also working in partnership with Syracuse University, to engineer systems consisting of modular wicking filters tied into duct work and water supplies, essentially tying plant-based filters into heating, ventilation, and air conditioning (HVAC) systems. Also, the company has recently begun to assess the ability of the EcoPlanter to remove formaldehyde from interior environments. Wolverton Environmental is also in talks with designers of the new Stennis Visitor's Center, who are interested in using its designs for indoor air-quality filters

Source record↗
NASA NTRS2010

Cleaning Processes across NASA Centers

All significant surfaces of the hardware must be pre-cleaned to remove dirt, grit, scale, corrosion, grease, oil and other foreign matter prior to any final precision cleaning process. Metallic parts shall be surface treated (cleaned, passivated, pickled and/or coated) as necessary to prevent latent corrosion and contamination.

Hammond, John M.↗
NASA NTRS2006

Cleaning Carbon Nanotubes by Use of Mild Oxygen Plasmas

Experiments have shown that it is feasible to use oxygen radicals (specifically, monatomic oxygen) from mild oxygen plasmas to remove organic contaminants and chemical fabrication residues from the surfaces of carbon nanotubes (CNTs) and metal/CNT interfaces. A capability for such cleaning is essential to the manufacture of reproducible CNT-based electronic devices. The use of oxygen radicals to clean surfaces of other materials is fairly well established. However, previously, cleaning of CNTs and of graphite by use of oxygen plasmas had not been attempted because both of these forms of carbon were known to be vulnerable to destruction by oxygen plasmas. The key to success of the present technique is, apparently, to ensure that the plasma is mild . that is to say, that the kinetic and internal energies of the oxygen radicals in the plasma are as low as possible. The plasma oxygen-radical source used in the experiments was a commercial one marketed for use in removing hydrocarbons and other organic contaminants from vacuum systems and from electron microscopes and other objects placed inside vacuum systems. In use, the source is installed in a vacuum system and air is leaked into the system at such a rate as to maintain a background pressure of .0.56 torr (.75 Pa). In the source, oxygen from the air is decomposed into monatomic oxygen by radio-frequency excitation of a resonance of the O2 molecule (N2 is not affected). Hence, what is produced is a mild (non-energetic) oxygen plasma. The oxygen radicals are transported along with the air molecules in the flow created by the vacuum pump. In the experiments, exposure to the oxygen plasma in this system was shown to remove organic contaminants and chemical fabrication residues from several specimens. Many high-magnification scanning electron microscope (SEM) images of CNTs were taken before and after exposure to the oxygen plasma. As in the example shown in the figure, none of these images showed evidence of degradation of CNT structures.

Petkov, Mihail↗
NASA NTRS2011

US Clean Energy Sector and the Opportunity for Modeling and Simulation

The following paper sets forth the current understanding of the US clean energy demand and opportunity. As clean energy systems come online and technology is developed, modeling and simulation of these complex energy programs provides an untapped business opportunity. The US Department of Defense provides a great venue for developing new technology in the energy sector because it is demanding lower fuel costs, more energy efficiencies in its buildings and bases, and overall improvements in its carbon footprint. These issues coupled with the security issues faced by foreign dependence on oil will soon bring more clean energy innovations to the forefront (lighter batteries for soldiers, alternative fuel for jets, energy storage systems for ships, etc).

Inge, Carole Cameron↗
NASA NTRS2013

Ultra Pure Water Cleaning Baseline Study on NASA JSC Astromaterial Curation Gloveboxes

Future sample return missions will require strict protocols and procedures for reducing inorganic and organic contamination in isolation containment systems. In 2012, a baseline study was orchestrated to establish the current state of organic cleanliness in gloveboxes used by NASA JSC astromaterials curation labs [1, 2]. As part of this in-depth organic study, the current curatorial technical support procedure (TSP) 23 was used for cleaning the gloveboxes with ultra pure water (UPW) [3-5]. Particle counts and identification were obtained that could be used as a benchmark for future mission designs that require glovebox decontamination. The UPW baseline study demonstrates that TSP 23 works well for gloveboxes that have been thoroughly degreased. However, TSP 23 could be augmented to provide even better glovebox decontamination. JSC 03243 could be used as a starting point for further investigating optimal cleaning techniques and procedures. DuPont Vertrel XF or other chemical substitutes to replace Freon- 113, mechanical scrubbing, and newer technology could be used to enhance glovebox cleanliness in addition to high purity UPW final rinsing. Future sample return missions will significantly benefit from further cleaning studies to reduce inorganic and organic contamination.

Calaway, Michael J.↗
NASA NTRS2013

Cleaning Study of Genesis Sample 60487

The Genesis mission collected solar wind and brought it back to Earth in order to provide precise knowledge of solar isotopic and elemental compositions. The ions in the solar wind were stopped in the collectors at depths on the order of 10 to a few hundred nanometers. This shallow implantation layer is critical for scientific analysis of the composition of the solar wind and must be preserved throughout sample handling, cleaning, processing, distribution, preparation and analysis. Particles of Genesis wafers, brine from the Utah Testing Range and an organic film have deleterious effects on many of the high-resolution instruments that have been developed to analyze the implanted solar wind. We have conducted a correlative microscopic study of the efficacy of cleaning Genesis samples with megasonically activated ultrapure water and UV/ozone cleaning. Sample 60487, the study sample, is a piece of float-zone silicon from the B/C array approximately 4.995mm x 4.145 mm in size

Kuhlman, Kim R.↗
NASA NTRS2013

'How To' Clean Room Video

One of the projects that I am completing this summer is a Launch Services Program intern 'How to' set up a clean room informational video. The purpose of this video is to go along with a clean room kit that can be checked out by employees at the Kennedy Space Center and to be taken to classrooms to help educate students and intrigue them about NASA. The video will include 'how to' set up and operate a clean room at NASA. This is a group project so we will be acting as a team and contributing our own input and ideas. We will include various activities for children in classrooms to complete, while learning and having fun. Activities that we will explain and film include: helping children understand the proper way to wear a bunny suit, a brief background on cleanrooms, and the importance of maintaining the cleanliness of a space craft. This project will be shown to LSP management and co-workers; we will be presenting the video once it is completed.

McCarty, Kaley Corinne↗
NASA NTRS2014

ToF-SIMS Investigation of the Effectiveness of Acid-Cleaning procedures for Genesis Solar Wind Collectors

ToF-SIMS images of Genesis sample surfaces contain an incredible amount of important information, but they also show that the crash-derived surface contamination has many components, presenting a challenge to cleaning. Within the variability, we have shown that there are some samples which appear to be clean to begin with, e.g. 60471, and some are more contaminated. Samples 60493 and 60500 are a part of a focused study of the effectiveness of aqua regia and/or sulfuric acid cleaning of small flight Si implanted with Li-6 using ToF-SIMS.

Goreva, Y. S.↗
NASA NTRS2014

Cellulose Acetate Replica Cleaning Study of Genesis Non-Flight Sample 3CZ00327

The Genesis mission collected solar wind and brought it back to Earth in order to provide precise knowledge of solar isotopic and elemental compositions. The ions in the solar wind were stopped in the collectors at depths on the order of 10 to a few hundred nanometers. This shallow implantation layer is critical for scientific analysis of the composition of the solar wind and must be preserved throughout sample handling, cleaning, processing, distribution, preparation and analysis. We are working interactively with the community of scientists analyzing Genesis samples, using our unique laboratory facilities -- and, where needed, our unique cleaning techniques -- to significantly enhance the science return from the Genesis mission. This work is motivated by the need to understand the submicron contamination on the collectors in the Genesis payload as recovered from the crash site in the Utah desert, and -- perhaps more importantly -- how to remove it. That is, we are evaluating the effectiveness of the wet-chemical "cleaning" steps used by various investigators, to enable them to design improved methods of stripping terrestrial contamination from surfaces while still leaving the solar-wind signal intact.

Kuhlman, K. R.↗
NASA NTRS2015

Replacement of Hydrochlorofluorocarbon (HCFC) -225 Solvent for Cleaning and Verification Sampling of NASA Propulsion Oxygen Systems Hardware, Ground Support Equipment, and Associated Test Systems

Since the 1990's, NASA's rocket propulsion test facilities at Marshall Space Flight Center (MSFC) and Stennis Space Center (SSC) have used hydrochlorofluorocarbon-225 (HCFC-225), a Class II ozone-depleting substance, to safety clean and verify the cleanliness of large scale propulsion oxygen systems and associated test facilities. In 2012 through 2014, test laboratories at MSFC, SSC, and Johnson Space Center-White Sands Test Facility collaborated to seek out, test, and qualify an environmentally preferred replacement for HCFC-225. Candidate solvents were selected, a test plan was developed, and the products were tested for materials compatibility, oxygen compatibility, cleaning effectiveness, and suitability for use in cleanliness verification and field cleaning operations. Honewell Soltice (TradeMark) Performance Fluid (trans-1-chloro-3,3, 3-trifluoropropene) was selected to replace HCFC-225 at NASA's MSFC and SSC rocket propulsion test facilities.

Burns, H. D.↗
NASA NTRS2010

Supercritical CO2 Cleaning for Planetary Protection and Contamination Control

We have designed and built a prototype Supercritical CO? Cleaning (SCC) system at JPL. The key features of the system are: 1) the parts inside a high-pressure vessel can be rotated at high speeds; 2) the same thermodynamic condition is maintained during First-In First-Out flushing to keep solvent power constant; and 3) the boil-off during decompression is induced in a separate vessel downstream. Our goal is to demonstrate SCC's ability to remove trace amounts of microbial and organic contaminants down to parts per billion levels from spacecraft material surfaces for future astrobiology missions. The initial cleaning test results showed that SCC can achieve cleanliness levels of 0.01 microgram/cm(sup 2) or less for hydrophobic contaminants such as dioctyl phthalate and silicone and it is less effective in the removal and inactivation of the hydrophilic bacterial spores as expected. However, with the use of a polar co-solvent, the efficacy may improve dramatically. The same results were obtained using liquid CO?. This opens up the possibility of using subcritical cleaning conditions, which may prove to be more compatible with certain spacecraft hardware.

Lin, Ying↗
NASA NTRS2015

Clothes Cleaning Studies for Long Duration Manned Missions

Imagine how much could be saved in just 5 years if the garments that are sent to space are reduced by half. My project consisted in analyzing the efficiency of steam cleaning with and without pretreatment of selected garments. Crewmembers wear clothes for a certain period of time, and then these garments are discarded. Having crewmembers wearing their clothes for longer time while giving them the opportunity of reusing the garments (which at the moment is not possible) will reduce costs considerably. More importantly, it will build the path for sustaining human presence in deep space. In addition, reusing cleaned clothes will help crewmembers be in a more hygienic environment because the amount of trash will be reduced. By limiting the amount of garments that are sent, volume and mass will be reduced. As a result, there will be more space to pack other necessary goods. The main duties within the project were to develop a pre wash procedure that will be used for all of the fabrics (4 different fabrics were included in the experiment), to establish a time for the process of cleaning the garments with steam, to know the amount of oil and salt solution necessary to soil the fabric and that will be completely absorbed by the fabric, to determine the amount of chemical agent to use for removing the stains, to create a matrix with the SAS software that will have all the possible combinations to carry out during the experiment when soiling the shirts, to measure the stains before and after the steam process, to measure the cleanliness of the fabric before and after with the use of the Gray Scale for Staining, and to find out whether or not the observations are valid and useful.

Tamsen, Maria↗
NASA NTRS2017

Effects of Contamination and Cleaning on Parachute Structural Textile Elements

Throughout their lifecycle, parachute textiles come into contact with various other substances. This contact may occur during manufacturing and repair, storage and transportation, packing, or actual use. While this interaction does not always result in negative repercussions, it may cause a loss in material strength. This paper examines the strength degradation due to several contaminants as well as the effects of cleaning agents on common parachute materials. Materials tested were: Kevlar cord and webbing, Nylon broadcloth and webbing, and Vectran cord; all of these constitute the major structural elements for CPAS (Capsule Parachute Assembly System), the parachute system for the NASA Orion Crew Module. Contaminants tested were: sewing machine oil, dried stamping ink, dirt, basting glue, Sergene, and rust. Recommendations for cleaning (or not cleaning) these materials with respect to each of the contaminants are given in this paper, as well as recommendations for future tests.

Mollmann, Catherine↗
NASA NTRS2019

Firbimatic Vacuum Degreaser Cleaning Study

The purpose of this cleaning study was to establish the baseline of contaminants that can be removed using the Firbimatic Multisolvent 50-volt vacuum degreaser using Kyzen’s Metalnox® M6386 Solvent on 2219 aluminum alloy panels. Four different cleaning methods were used with six known contaminants. For each contaminant, five panels were contaminated—one was kept as a control, and the remaining four were cleaned using the vacuum degreaser. All applicable NASA, company, laboratory, and test-specific standard test practices were followed. Pre- and post-test results and photographs can be found in the appendices.

Morris, B. D.↗
DOE OSTI2025

Clean Energy for the Battery-to-EV Supply Chain: A Roadmap for Indonesia - Summary Brief

Indonesia has a unique opportunity to support the clean energy transition, enhance energy security, and spur economic growth with local battery manufacturing, bridging from the material supply all the way to pack designs and, ultimately, the manufacturing of electric cars. Following the elevation of United States and Indonesia relations to a Comprehensive Strategic Partnership, leaders of both countries highlighted the importance of Net Zero World support for Indonesia's energy transition, including collaboration on low-carbon battery supply chains. In support of this agreement, Net Zero World has partnered with Indonesia's Ministry of Energy and Mineral Resources and other Indonesian partners to chart actionable steps for establishing a clean, resilient battery supply chain and circular economy. This partnership aims to position Indonesia as a regional leader in clean energy and can help attract investment in the domestic battery and electric vehicle (EV) sectors.

batteries↗
DOE OSTI2025

NOVEL METHODS FOR IN SITU HIGH DENSITY SURFACE CLEANING SCRUBBING OF ULTRAHIGH VAC LONG NARROW TUBES TO REDUCE SECONDARY ELECTRON YIELD AND OUT GASSING

This project developed new methods for cleaning the inside surfaces of very long, narrow vacuum tubes used in particle accelerators. Traditional cleaning approaches are expensive, slow, or difficult to implement in accelerator tunnels. We designed and tested a portable plasma discharge cleaning system that uses lower-cost microwave and magnetron technologies to reduce outgassing and secondary electron emission from stainless steel and copper surfaces. The system, called the Plasma Discharge Test System (PDTS), allows accelerator components to be scrubbed more efficiently, which can improve performance and reduce maintenance costs for research and industrial applications.

POOLE, JOE HENRY [PRESIDENT]↗