50608: Waste Stream Profile, TA-55 TRP-III Fire System Replacement System-Asphalt for Recycle
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Large-diameter trees store disproportionally massive amounts of carbon and are a major driver of carbon cycle dynamics in forests worldwide. In the temperate forests of the western United States, proposed changes to Forest Plans would significantly weaken protections for a large portion of trees greater than 53 cm (21 inches) in diameter (herein referred to as “large-diameter trees”) across 11.5 million acres (~4.7 million ha) of National Forest lands. This study is among the first to report how carbon storage in large trees and forest ecosystems would be affected by a proposed policy. We examined the proportion of large-diameter trees on National Forest lands east of the Cascade Mountains crest in Oregon and Washington, their contribution to overall aboveground carbon (AGC) storage, and the potential reduction in carbon stocks resulting from widespread harvest. We analyzed forest inventory data collected on 3,335 plots and found that large trees play a major role in the accumulated carbon stock of these forests. Tree AGC (kg) increases sharply with tree diameter at breast height (DBH; cm) among five dominant tree species. Large trees accounted for 2.0 to 3.7% of all stems (DBH ≥ 1” or 2.54 cm) among five tree species; but held 33 to 46% of the total AGC stored by each species. Pooled across the five dominant species, large trees accounted for 3% of the 636,520 trees occurring on the inventory plots but stored 42% of the total AGC. A recently proposed large-scale vegetation management project that involved widespread harvest of large trees, mostly grand fir, would have removed ~44% of the AGC stored in these large-diameter trees, and released a large amount of carbon dioxide to the atmosphere. Given the urgency of keeping additional carbon out of the atmosphere and continuing carbon accumulation from the atmosphere to protect the climate system, it would be prudent to continue protecting ecosystems with large trees for their carbon stores, and also for their co-benefits of habitat for biodiversity, resilience to drought and fire, and microclimate buffering under future climate extremes.
Textile and clothing specifications for space activities are discussed, emphasizing a chronological and utilitarian role. New fabrication techniques led to the Mercury Space Suit, a constant-wear hybrid of the omni-environmental full pressure suit used by high-flying pilots of the 1950s. The Gemini program (1964-1966) provided the first specifically designed protective clothing assembly for both intra- and extravehicular operations. The G4C, used for EV (extravehicular) activities, protected the astronaut against solar radiation, heat loss, and meteoroid penetration. The clothing for the Apollo program (1968-1975) mirrored a greater concern for fire safety with Durette (a halogenated polyamide) and PBI (polybenzimadazole) widely used for intravehicular garments. With the advent of the Shuttle program, cabin pressure and composition were changed from 6 psi, 100% oxygen to 9-14 psi, 23.4% oxygen, 76.6% N2. As a result, 'off-the-shelf' materials were used without compromising fire safety. Reusability was stressed, as textile costs and durability were now important selection criteria noting that existing textile materials will probably be adequate for the next 20 years of space operations and research. A portable lunar survival shelter made of textiles is being developed; and a preliminary design for an EV 'tunnel suit system' (an access tunnel and homoform work station) is already in existence.
The task of managing hydrogen entry into elevated temperature structural materials employed in turbomachinery is a critical engineering area for propulsion systems employing hydrogen or decomposable hydrocarbons as fuel. Extant structural materials, such as the Inconel series, are embrittled by the ingress of hydrogen in service, leading to a loss of endurance and general deterioration of load-bearing dependability. Although the development of hydrogen-insensitive material systems is an obvious engineering option, to date insensitive systems cannot meet the time-temperature-loading service extremes encountered. A short-term approach that is both feasible and technologically sound is the development and employment of hydrogen barrier coatings. The present project is concerned with developing, analyzing, and physically testing laminate composite hydrogen barrier systems, employing Inconel 718 as the structural material to be protected. Barrier systems will include all metallic, metallic-to-ceramic, and, eventually, metallic/ceramic composites as the lamellae. Since space propulsion implies repetitive engine firings without earth-based inspection and repair, coating durability will be closely examined, and testing regimes will include repetitive thermal cycling to simulate damage accumulation. The target accomplishments include: generation of actual hydrogen permeation data for metallic, ceramic-metallic, and hybrid metallic/ceramic composition barrier systems, practically none of which is currently extant; definition of physical damage modes imported to barrier systems due to thermal cycling, both transient temperature profiles and steady-state thermal mismatch stress states being examined as sources of damage; and computational models that incorporate general laminate schemes as described above, including manufacturing realities such as porosity, and whatever defects are introduced through service and characterized during the experimental programs.
Several uses of thick-film technology in solar cell fabrication are discussed. Wrap-around contacts are obtained by first printing and firing a dielectric over the edge and subsequently applying a low-firing temperature conductor. Interconnection of cells into arrays can be achieved by printing and co-firing thick-film pastes, soldering, or with heat-curing conductive epoxies on low-cost substrates. Despite ongoing research, printed (thick) film vitreous protective coatings do not yet offer sufficient optical uniformity and transparency for use on silicon. Ohmic contacts on n- and p-type silicon are considered.
This Per- and Polyfluoroalkyl Substances (PFAS) Confirmatory Sampling (CS) Report was prepared by AECOM Technical Services, Inc. (AECOM) for the National Aeronautics and Space Administration (NASA) under Contract 80KSC019D0010, Task Order 80KSC021F0096. The purpose of this report is to document CS activities at the South Repeater Building, Solid Waste Management Unit (SWMU) 121, formerly known as the Area 3 Repeater Building (A3RB). A Phase I SWMU Assessment and Confirmatory Sampling Report (NASA 2019) and a Phase II and III SWMU Assessment and Confirmatory Sampling Report (NASA 2022b) were previously submitted detailing Center-Wide assessment activities performed at the John F. Kennedy Space Center (KSC) in Florida that identified 33 locations of concern and 19 areas of potential concern at KSC associated with the storage, use, or release of materials containing PFAS. A review of the analytical results from investigation derived waste samples collected in 2020 from the South Repeater Building area indicated concentrations of perfluorooctanesulfonic acid (PFOS) were above Florida Department of Environmental Protection (FDEP) provisional Groundwater Cleanup Target Levels of 70 nanograms per liter (ng/L) at a concentration of 1,750 ng/L. Following this review, the KSC Fire Chief was contacted; the Chief recalled fighting a brush fire in 1998 in the area, during which an unknown volume of aqueous film-forming foam was used to extinguish the fire. The Phase II and Phase III SWMU Assessment Report recommended this area proceed to CS. Historical results in this area are provided in Appendix A . PFAS CS activities were contracted at the South Repeater Building. Initial CS activities were conducted in accordance with the PFAS Assessment and Mitigation Work Plan (AECOM 2022), which was submitted to the NASA Remediation Project Management team and accepted by the team on November 1 and 8, 2021. The objectives of the PFAS CS were to: - - Confirm and begin to assess the extent of PFAS affected media in the South Repeater Building area. - - Identify locations for groundwater, soil, surface water, and soil core sampling. - - Qualitatively characterize the migration potential of released PFAS to environmental media (soil, groundwater, and surface water). The following activities were completed to meet the PFAS CS objectives: - - Installation of monitoring wells via direct push technology (DPT) and rotosonic techniques - - Groundwater, soil, and surface water sampling - - Collection of soil cores to evaluate site lithology - - Development of initial PFAS plume characterization
Fire is a nationally and globally significant process that strongly affects human–dominated and wild landscapes. Even though fire can be devastating, wildland fire is a natural and integral force on our landscapes, providing value by decreasing fuels at the Wildland Urban Interface (WUI) to promote safe communities. However, uncontained wildfires can devastate communities, threaten our health, and result in substantial economic losses. There has been greater than a $50B increase in wildfire insurance claims from 2017-2021, which has been exacerbated by climate change. Our partners at Kettle reinsurance are focused on building a smarter reinsurance model for protecting today’s globalized world from the catastrophic effects of climate change. Our objective is to develop the world's first grid-based wildfire probability product using multiple sources of satellite data to determine whether a ‘conflagration' (fire larger than 999+ acres) has ‘breached’ a grid cell. This will substantially decrease the time it takes for homeowners to receive payouts, from over a year to a couple months. Working with our partners at Kettle reinsurance, we use multiple satellites and ancillary data to weigh the likelihood of fire, based on a number of sources that verify a fire burning in a grid cell and the level of confidence in the data source. For example, Sentinel-2 vegetation-change indices have a higher level of confidence than VIIRS (Visible Infrared Imaging Radiometer Suite) active-fire detection data; and VIIRS active-fire detection data have a higher-level of confidence than MODIS (Moderate Resolution Imaging Spectroradiometer) active-fire detection data. The first iteration has been developed for responding to wildfires in California, with the possibility to expand nationwide and globally.
Even though fire can be devastating, wildland fire is a natural and integral force on our landscapes, providing value by decreasing fuels at the Wildland Urban Interface (WUI) to promote safe communities. However, uncontained wildfires can devastate communities, threaten our health, and result in substantial economic losses. There has been greater than a $50B increase in wildfire insurance claims from 2017-2021, which has been exacerbated by climate change. Our partners at Kettle reinsurance are focused on building a smarter reinsurance model for protecting today’s globalized world from the catastrophic effects of climate change. Our objective is to develop a high-confidence grid-based wildfire burn product using multiple sources of satellite data to determine whether a ‘conflagration' (fire larger than 999+ acres) has ‘breached’ a grid cell. This product will substantially decrease the time it takes for homeowners to receive payouts, from over a year to a couple months. Working with our partners at Kettle reinsurance, we use VIIRS (Visible Infrared Imaging Radiometer Suite) 375 m fire detections and Sentinel-2 10 m satellite imagery to create a 20-m gridded fire burn product. Our process is based on the level of confidence in the data source and takes into account vegetation change throughout the life of the fire. For example, Sentinel-2 vegetation-change indices have a higher level of confidence when congruent with VIIRS active-fire detection data, rather than VIIRS detections alone. We have also verified our fire burn product against MODIS/ASTER Airborne Simulator (MASTER) Infrared (IR) data from the Fire Influence on Regional to Global Environments Experiment - Air Quality (FIREX-AQ) 2019 campaign, with 88% overall agreement. The first iteration has been developed for responding to wildfires in California, with the possibility to expand nationwide and globally.
The purpose of this project was to create a fire model of the facility. Results from the model will be used to establish standoff distances from combustible fuel packages in the facility, in order to protect material from a thermal event.
Selenium is released into the environment via anthropogenic activities such as coal combustion. The U.S. Environmental Protection Agency’s Effluent Limitation Guideline (ELG) Rule limits the release of selenium species into U.S. waterways. To meet the ELG limit for selenium, coal-fired power plants must treat the wastewater produced by the flue gas desulfurization (FGD) systems. Selenium removal is of interest because small changes of the concentrations of selenium in the environment can cause detrimental ecological consequences. Biological treatment is used to remediate this wastewater, but little is known about the individual species in the microbial consortium that reduce toxic water-soluble selenium oxyanions to insoluble elemental selenium. To optimize current biological treatment capabilities of this water, the selenium-reducing capabilities must be leveraged. In order to do so, the selenium-reducing bacteria (SeRB) in biological treatment systems must be characterized. This study will be the first to characterize the microbial consortia from a real FGD WW biological treatment system and provide insights on how to better achieve selenium removal via biological treatment. This work will provide insights into the microorganisms predominantly responsible for the reduction of selenium oxyanions in FGD wastewater biological treatment systems, which can be used to better optimize more efficient biological treatment strategies of this industrial waste.
Spray head equipped with four-nozzle turret mixes two reactive components of polyurethane and polyisocyanurate foam insulating material and sprays reacting mixture onto surface to be insulated. If nozzle in use becomes clogged, fresh one automatically rotated into position, with minimal interruption of spraying process. Incorporates features recirculating and controlling pressures of reactive components to maintain quality of foam by ensuring proper blend at outset. Also used to spray protective coats on or in ships, aircraft, and pipelines. Sprays such reactive adhesives as epoxy/polyurethane mixtures. Components of spray contain solid-particle fillers for strength, fire retardance, toughness, resistance to abrasion, or radar absorption.
Daily life for firefighters consists of working with life-threatening hazards in hostile environments. A major hazard is excessive ambient heat. New hazards have arisen from protective gear that was intended to increase survival time of firefighters while finding and rescuing victims. The insulation is so good now that a firefighter's metabolic heat buildup cannot escape. This forces body core temperatures to life threatening levels in about 20 minutes of moderate activity. Using NASA space suit technology, Oceaneering Space Systems developed a liquid cooling garment prototype that will remove up to 250 watts of metabolic heat. After testing and certification as an approved accessory for firefighter use, this garment will be available for use by any individual encapsulated in protective clothing. This demonstration will present a high surface area circulated liquid cooling garment displayed on a mannequin and available for attendees to try on to experience the effects of active cooling.
M-3 Focused Experiments is a group at Los Alamos National Lab (LANL) and is under the Dynamic Experiments Division. Their work surrounds the diagnostics and study of explosives and their interaction with materials. The data collected is used to better understand the erratic nature of explosions and high velocity projectiles. Through better comprehension of this science, the overall national security will be improved while innovations are made along the way. Despite the strong drive for research and development, the lab holds safety above all else and constantly updates procedures to protect LANL employees and their environment. At any time, there are multiple projects going on at once within the team and I am tasked with assisting the Firing Site Leaders and various research diagnosticians in any way possible with the setup, testing, and execution of data collection for each experiment. Such data includes velocity, fragmentation characteristics, and the spread of energy across the material to name a few. During my summer employment with the lab, my main goal is to maintain a questioning attitude and learn as much possible about the research and development side of science and engineering. Throughout the duration of the Co-op, many experiments will take place at specially designed firing sites which is where I will be spending most of my time.
Since its inception in 1958, the National Aeronautics and Space Administration s (NASA) role in civil aeronautics has been to develop high-risk, high-payoff technologies to meet critical national aviation challenges. Following the events of Sept. 11, 2001, NASA recognized that it now shared the responsibility for improving homeland security. The NASA Strategic Plan was modified to include requirements to enable a more secure air transportation system by investing in technologies and collaborating with other agencies, industry, and academia. NASA is conducting research to develop and advance innovative and commercially viable technologies that will reduce the vulnerability of aircraft to threats or hostile actions, and identify and inform users of potential vulnerabilities in a timely manner. Presented in this paper are research plans and preliminary status for mitigating the effects of damage due to direct attacks on civil transport aircraft. The NASA approach to mitigation includes: preventing loss of an aircraft due to a hit from man-portable air defense systems; developing fuel system technologies that prevent or minimize in-flight vulnerability to small arms or other projectiles; providing protection from electromagnetic energy attacks by detecting directed energy threats to aircraft and on/off-board systems; and minimizing the damage due to high-energy attacks (explosions and fire) by developing advanced lightweight, damage-resistant composites and structural concepts. An approach to preventing aircraft from being used as weapons of mass destruction will also be discussed.
The NASA Space Launch System (SLS) vehicle is composed of four RS-25 liquid oxygen and hydrogen rocket engines in the Core Stage (CS). The SLS Core Stage went through Green Run hot-fire testing at NASA Stennis Space Center’s B-2 test facility in 2021. The main goal of this testing was to confirm Core Stage tanking, propulsion and thrust vector control systems operations and performance to verify with predicted models. Two hot-fire (HF) test sequences were performed with the first one (HF1) in January for a test duration of 70 seconds and the second (HF2) testing completed in March for a test duration of 500 seconds. This paper focuses on the base heating anomalies observed during HF1 and HF2 where an extensive fire was observed along the Core Stage base heat shield during test operations. This environment was not anticipated and led to extensive unplanned damage to the thermal protection system which was augmented for flight. Green Run observations also led to a reassessment of flight environments for Artemis I. This paper discusses the potential cause of the anomalies, the flow physics, the reconstructed base environments, and mitigation plans for HF2 and flight.
The NASA Space Launch System (SLS) vehicle is composed of four RS-25 liquid oxygen and hydrogen rocket engines in the Core Stage (CS). The SLS Core Stage went through Green Run hotfire testing at NASA Stennis Space Center’s B-2 test facility in 2021. The main goal of this testing was to confirm Core Stage tanking, propulsion and thrust vector control systems operations and performance to verify with predicted models. Two hot-fire (HF) test sequences were performed with the first one (HF1) in January for a test duration of 70 seconds and the second (HF2) testing completed in March for a test duration of 500 seconds. This paper focuses on the base heating anomalies observed during HF1 and HF2 where an extensive fire was observed along the Core Stage base heat shield during test operations. This environment was not anticipated and led to extensive unplanned damage to the thermal protection system which was augmented for flight. Green Run observations also led to a reassessment of flight environments for Artemis I. This paper discusses the potential cause of the anomalies, the flow physics, the reconstructed base environments, and mitigation plans for HF2 and flight.
The self-healing fuse is a very fast acting current overload protective device which opens and recloses in a few milliseconds. The fuse confines a mercury column in an insulated channel and returns the mercury to the channel after firing. Ratings 5 to 50 A at 600 peak volts are possible with a life of hundreds of cycles. Compared to conventional fuses, much less fault current energy fires the fuse by heating the mercury to boiling temperature. Next an arc discharge develops while explosive forces expel the liquid mercury from the channel. Then the high impedance arc either extinguishes immediately, or operates for a few milliseconds, until a switch opens the circuit.
The purpose of this innovation is to use microstrain gauges to monitor minute changes in temperature along with material properties of the metal cans and pouches used in the construction of lithium-ion cells. The sensitivity of the microstrain gauges to extremely small changes in temperatures internal to the cells makes them a valuable asset in controlling the hazards in lithium-ion cells. The test program on lithium-ion cells included various cell configurations, including the pouch type configurations. The thermal properties of microstrain gauges have been found to contribute significantly as safety monitors in lithium-ion cells that are designed even with hard metal cases. Although the metal cans do not undergo changes in material property, even under worst-case unsafe conditions, the small changes in thermal properties observed during charge and discharge of the cell provide an observable change in resistance of the strain gauge. Under abusive or unsafe conditions, the change in the resistance is large. This large change is observed as a significant change in slope, and this can be used to prevent cells from going into a thermal runaway condition. For flexible metal cans or pouch-type lithium-ion cells, combinations of changes in material properties along with thermal changes can be used as an indication for the initiation of an unsafe condition. Lithium-ion cells have a very high energy density, no memory effect, and almost 100-percent efficiency of charge and discharge. However, due to the presence of a flammable electrolyte, along with the very high energy density and the capability of releasing oxygen from the cathode, these cells can go into a hazardous condition of venting, fire, and thermal runaway. Commercial lithium-ion cells have current and voltage monitoring devices that are used to control the charge and discharge of the batteries. Some lithium-ion cells have internal protective devices, but when used in multi-cell configurations, these protective devices either do not protect or are themselves a hazard to the cell due to their limitations. These devices do not help in cases where the cells develop high impedance that suddenly causes them to go into a thermal runaway condition. Temperature monitoring typically helps with tracking the performance of a battery. But normal thermistors or thermal sensors do not provide the accuracy needed for this and cannot track a change in internal cell temperatures until it is too late to stop a thermal runaway.