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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2015

Characterization of Synthetic and Natural Manganese Oxides as Martian Analogues

Recent discoveries of highly concentrated manganese oxides in Gale Crater and on the rim of Endeavour Crater by the Mars Science Laboratory Curiosity and Mars Exploration Rover Opportunity, respectively, imply more highly oxidizing aqueous conditions than previously recognized. Manganese oxides are a significant environmental indicator about ancient aqueous conditions, provided the phases can be characterized reliably. Manganese oxides are typically fine-grained and poorly crystalline, making the mineral structures difficult to determine, and they generally have very low visible reflectance with few distinctive spectral features in the visible to near infrared, making them a challenge for interpretation from remote sensing data. Therefore, these recent discoveries motivate better characterization using methods available on Mars, particularly visible to near infrared (VNIR) spectroscopy, X-ray diffractometry (XRD), and compositional measurements. Both rovers have complementary instruments in this regard. Opportunity is equipped with its multispectral visible imager, Pancam, and an Alpha Particle X-ray Spectrometer (APXS), and Curiosity has the multispectral Mastcam, ChemCam (laser-induced breakdown spectroscopy and passive spectroscopy), and APXS for in situ characterization, and ChemMin (XRD) for collected samples.

Fox, V. K.↗
NASA NTRS2015

Monitoring Natural Events Globally in Near Real-Time Using NASA's Open Web Services and Tools

Since 1960, NASA has been making global measurements of the Earth from a multitude of space-based missions, many of which can be useful for monitoring natural events. In recent years, these measurements have been made available in near real-time, making it possible to use them to also aid in managing the response to natural events. We present the challenges and ongoing solutions to using NASA satellite data for monitoring and managing these events.

web services↗
NASA NTRS2015

OLTARIS - Overview and Recent Updates

The On-Line Tool for the Assessment of Radiation in Space (OLTARIS) is a web-based set of tools and models that allow engineers and scientists to assess the effects of space radiation in spacecraft, habitats, rovers, and spacesuits. The site is intended to be a design tool for those studying the effects of space radiation for current and future missions as well as a research tool for those developing advanced material and shielding concepts. The tools and models are built around the HZETRN radiation transport code and are currently focused on human-related responses. OLTARIS was deployed in 2008. Since that time, many improvements and additional capabilities have been added to the site. The purpose of this poster/presentation is to give an overview of the current capabilities of OLTARIS and focus on the updates to the site since the last workshop presentation in 2014. OLTARIS currently has 240 active accounts - 87 accounts are government (including NASA, ORNL, JPL, AFRL, and FAA), 76 are university professors/researchers/students, and 51 are industry (including Boeing, Space X, Lockheed-Martin, ATK, Northrup Grumman, and Bigelow Aerospace). There have been 14,000 jobs run through OLTARIS since counting began in November 2009. ITAR restrictions were recently reversed, so the site is now available to registered users worldwide.

Sandridge, C. A.↗
NASA NTRS2018

Undirectional Carbon Nanotube Yarn/Polymer Composites

Carbon nanotubes (CNTs) are one-dimensional nanomaterials with outstanding electrical and thermal conductivities and mechanical properties at the nanoscale. With these superior physical properties, CNTs are very attractive materials for future light weight structural aerospace applications. Recent manufacturing advances have led to the availability of bulk formats of CNTs such as yarns, tapes, and sheets in commercial quantities, thus enabling the development of macroscale composite processing methods for aerospace applications. The fabrication of unidirectional CNT yarn/polymer composites and the effect of processing parameters such as resin type, number of CNT yarn layers, CNT yarn/resin ratio, consolidation method, and tension applied during CNT yarn winding on the mechanical properties of unidirectional CNT yarn composites are reported herein. Structural morphologies, electrical and thermal conductivities, and mechanical performance of unidirectional CNT yarn/polymer composites under tensile and short beam shear loads are presented and discussed. The application of higher tension during the winding process and elevated cure pressure during the press molding step afforded a compact structural morphology and reduced void content in the composite. However, the composite tensile strength was negligibly impacted by the fabrication parameters, such as cure pressure, winding tension, and resin chemistry, excepting resin content and number of CNT yarn layers. The tension winding method produced better quality and lower resin content CNT yarn composites compared to conventional prepregging methods, resulting in higher specific strength and modulus of the composites. The specific tensile strength of the CNT composite was approximately 69 % of the starting CNT yarn. Electrical and thermal conductivities of unidirectional CNT yarn/polymer composites were in the range of 1000 to 12000 S/cm and 22 to 45 W/mK, respectively.

Kim, Jae-Woo↗
NASA NTRS2018

Physics-Based Approach to Predict the Solar Activity Cycles

Observations of the complex highly non-linear dynamics of global turbulent flows and magnetic fields are currently available only from Earth-side observations. Recent progress in helioseismology has provided us some additional information about the subsurface dynamics, but its relation to the magnetic field evolution is not yet understood. These limitations cause uncertainties that are difficult take into account, and perform proper calibration of dynamo models. The current dynamo models have also uncertainties due to the complicated turbulent physics of magnetic field generation, transport and dissipation. Because of the uncertainties in both observations and theory, the data assimilation approach is natural way for the solar cycle prediction and estimating uncertainties of this prediction. I will discuss the prediction results for the upcoming Solar Cycle 25 and their uncertainties and affect of Ensemble Kalman Filter parameters to resulting predictions.

Physics-Based↗
NASA NTRS2014

AztechSat-1, a First Collaborative CubeSat Between NASA and Mexico

An international collaboration program for capacity building in space technology is being established between NASA and the Mexican Space Agency (AEM). Its objective is to develop a series of CubeSats collaboratively in a way that benefits both agencies. For AEM, this experience will support the development of human capital required for its space program. This project provides an opportunity for NASA future missions to benefit from commercially available technologies demonstrated in space. AEM was recently created by the Mexican Government to use and develop space technology in Mexico. Current AEM plans call for having the capability of developing its own communication satellites by 2030, so the need for having a Mexican cadre of space experts is mandatory. The program will start with the development and launching of AztechSat-1, the first AEM CubeSat project to be deployed from the International Space Station (ISS). Several public Mexican universities will participate in this project to demonstrate GlobalStar, a satellite communications provider using a constellation of LEO satellites, as an option for small satellite missions. AztechSat-1 mission objectives are:(1) Develop a flight ready CubeSat for deployment from the ISS; (2) Demonstrate GlobalStar´s Network as a method to advance communications in CubeSat missions. AztechSat-1 is envisioned as a 1U CubeSat and will be designed and constructed by Mexican graduate students from two major universities in Mexico: UNAM and IPN. The students will be mentored and supervised by researchers from NASA Ames Research Center (NARC). Flight acceptance tests are going to be done both at Mexican university labs as well as at NARC. Funding for the project will be provided concurrently by AEM, the Mexican participating universities, and other Mexican entities. The development of AztechSat-1 will emphasize the transfer of knowledge in space mission analysis and design, flight acceptance testing and other areas of space technology which are not well developed in Mexico yet. Mexican students will benefit from their mentoring from NASA researchers and will provide a multiplier effect in the development of the next generation of Mexican aerospace engineers. AztechSat-1 will be developed in a period of twelve months and will be launched by late 2015. AztechSat´s success will define the future of collaboration between NASA and AEM in capacity building. A plan for developing a series of AztechSat’s in a one per year basis, with increasing capabilities and complexity is currently being negotiated between NASA an AEM.

Martinez, Andres↗
NASA NTRS2018

Integrated Optimization of Mars Hybrid Solar-Electric/Chemical Propulsion Trajectories

NASA’s Human Exploration and Operation Mission Directorate is developing a reusable hybrid transportation architecture in which both chemical and solar-electric propulsion systems are used to deliver crew and cargo to the Martian sphere of influence. By combining chemical and solar-electric propulsions into a single spacecraft and applying each where it is the most effective, the hybrid architecture enables a series of Mars trajectories that are more fuel efficient than an all chemical propulsion architecture without significant increase to trip time. Solving the complex problem of low-thrust trajectory optimization coupled with the vehicle sizing requires development of an integrated trajectory analysis frame- work. Previous studies have utilized a more segmented optimization framework due to the limitation of the tools available. A new integrated optimization framework was recently developed to address the deficiencies of the previous methods that enables higher fidelity analysis to be performed and increases the efficiency of large design space explorations.

Chai, Patrick R.↗
NASA NTRSDate not supplied

In-Space Manufacturing and Planetary Surface Construction: A "Make It, Don't Take It" Approach to Long Duration Human Exploration

This presentation will focus on technology development efforts at NASA Marshall Space Flight Center (MSFC) related to the long term sustainability of human spaceflight operations. NASA’s in-space manufacturing (ISM) project is developing approaches for on-demand manufacturing of metals, printed electronics, and recycling. These technologies will be demonstrated onboard the International Space Station (ISS) before transitioning to more logistically remote platforms such as Gateway or a foundational lunar surface habitat. Based on quantitative analyses, the operations and logistics approach used for ISS (which relies on storage of a large volume of spares and frequent cargo resupply), will not be transferrable to long duration, long endurance missions beyond low earth orbit. The deployment of manufacturing and recycling technologies on crewed platforms will enable on-demand manufacturing of spares at the point of use and conversion of nuisance materials to manufacturing feedstock, reducing both launch mass and waste material. This talk will also include information on NASA’s 3D Printed Habitat Centennial Challenge, which concluded in 2019 and served to advance the state of the art for large scale 3D printing with indigenous materials similar to those which would be available on a planetary surface. MSFC also recently began work on the Moon-to-Mars Planetary Autonomous Construction Technologies (MMPACT) project, which seeks to demonstrate capabilities for the creation of infrastructure on the lunar surface via construction of landing pads and habitats with lunar regolith based materials.

materials↗
NASA NTRSDate not supplied

On-Demand Manufacturing of Electronics

The On-Demand Manufacturing of Electronics (ODME) project develops materials, processes, and device designs to enable electronics, sensors, and semiconductors to be produced in microgravity environments. The demonstration of these technologies provides a pathway for space-based manufacturing of circuits, wearables, energy storage devices, and other electronics. This has facilitated the terrestrial production of devices including a wide range of sensors, printed batteries, and circuits that are additively manufactured using techniques available on the Advanced Toolplate System (ATS). Recent parabolic flight campaigns conducted with the ATS suggest that direct ink write (DIW) technology is suitable for depositing functional material inks in reduced gravity environments. The development of the Advanced Toolplate system also includes several other new tools, including miniaturized versions of the direct write head, fused filament fabrication head, micro-mill, component pick & place head, and two newly developed deposition technologies, the Electrohydrodynamic (EHD) inkjet head (for semiconductors), and the Electrodeposition head (for high performance circuits). These experiments are designed to compare processing and material behavior in zero gravity versus ground-based data for validation of microgravity advantages and de-risking of future orbital demonstrations of these technologies. The ability to conduct experiments in microgravity is a pivotal step in enabling electronic manufacturing technology in space for both terrestrial and deep space applications.

Cadre Francis↗
DOE OSTI2024

Quantum Annealing for Real-World Machine Learning Applications

Optimizing the training of a machine learning pipeline is important for reducing training costs and improving model performance. One such optimizing strategy is quantum annealing, which is an emerging computing paradigm that has shown potential in optimizing the training of a machine learning model. The implementation of a physical quantum annealer has been realized by D-Wave systems and is available to the research community for experiments. Recent experimental results on a variety of machine learning applications have shown interesting results especially under the conditions where the performance of classical machine learning techniques are limited such as limited training data and high dimensional features. This chapter explores the application of D-Wave’s quantum annealer for optimizing machine learning pipelines for real-world classification problems. We review the application domains on which a physical quantum annealer has been used to train machine learning classifiers. We discuss and analyze the experiments performed on the D-Wave quantum annealer for applications such as image recognition, remote sensing imagery, security, computational biology, biomedical sciences, and physics. We discuss the possible advantages and the problems for which quantum annealing is likely to be advantageous over classical computation.

Kumar nath, Rajdeep↗
DOE OSTI2023

2023 Annual Report of Available Drawdowns for Each Oil Storage Cavern in the Strategic Petroleum Reserve

DOE maintains an up-to-date documentation of the number of available full drawdowns of each of the caverns at the U.S. Strategic Petroleum Reserve (SPR). This information is important for assessing the SPR’s ability to deliver oil to domestic oil companies expeditiously if national or world events dictate a rapid sale and deployment of the oil reserves. Sandia was directed to develop and implement a process to continuously assess and report the evolution of drawdown capacity, the subject of this report. This report covers impacts on drawdown availability due to SPR operations during Calendar Year 2022. A cavern has an available drawdown if, after that drawdown, the long-term stability of the cavern, the cavern field, or the oil quality are not compromised. Thus, determining the number of available drawdowns requires the consideration of several factors regarding cavern and wellbore integrity and stability, including stress states caused by cavern geometry and operations, salt damage caused by dilatant and tensile stresses, the effect of enhanced creep on wellbore integrity, and the sympathetic stress effect of operations on neighboring caverns. Finite-element geomechanical models have been used to determine the stress states in the pillars following successive drawdowns. By computing the tensile and dilatant stresses in the salt, areas of potential structural instability can be identified that may represent red flags for additional drawdowns. These analyses have found that many caverns will maintain structural integrity even when grown via drawdowns to dimensions resulting in a pillar-to-diameter ratio of less than 1.0. The analyses have also confirmed that certain caverns should only be completely drawn down one time. As the SPR caverns are utilized and partial drawdowns are performed to remove oil from the caverns (e.g., for oil sales, purchases, or exchanges authorized by the Congress or the President), the changes to the cavern caused by these procedures must be tracked and accounted for so that an ongoing assessment of the cavern’s drawdown capacity may be continued. A methodology for assessing and tracking the available drawdowns for each cavern is reiterated. This report is the latest in a series of annual reports, and it includes the baseline available drawdowns for each cavern, and the most recent assessment of the evolution of drawdown expenditures. A total of 222 million barrels of oil were released in calendar-year 2022. A nearly-equal amount of raw water was injected, resulting in an estimated 34 million barrels of cavern leaching. Twenty caverns have now expended a full drawdown. Cavern BC 18 has expended all its baseline available drawdowns, and has no drawdowns remaining. Cavern BM 103 has expended one of its two baseline drawdowns, and is now a single-drawdown cavern. All other caverns with an expenditure went from at-least-5 to at-least-4 remaining drawdowns.

02 PETROLEUM↗
NASA NTRS1990

Chemical evolution and the origin of life: cumulative keyword subject index 1970-1986

This cumulative subject index encompasses the subject indexes of the bibliographies on Chemical Evolution and the Origin of Life that were first published in 1970 and have continued through publication of the 1986 bibliography supplement. Early bibliographies focused on experimental and theoretical material dealing directly with the concepts of chemical evolution and the origin of life, excluding the broader areas of exobiology, biological evolution, and geochemistry. In recent years, these broader subject areas have also been incorporated as they appear in literature searches relating to chemical evolution and the origin of life, although direct attempts have not been made to compile all of the citations in these broad areas. The keyword subject indexes have also undergone an analogous change in scope. Compilers of earlier bibliographies used the most specific term available in producing the subject index. Compilers of recent bibliographies have used a number of broad terms relating to the overall subject content of each citation and specific terms where appropriate. The subject indexes of these 17 bibliographies have, in general, been cumulatively compiled exactly as they originally appeared. However, some changes have been made in an attempt to correct errors, combine terms, and provide more meaningful terms.

NASA Center HQS↗
DOE OSTI2021

A Review of Water and Climate Change Analysis in Electric Utility Integrated Resource Planning

The purpose of this paper is to examine the extent to which electric utility integrated resource plans (IRPs) evaluate the impact of water constraints on electric generation resource portfolios and the extent to which IRPs consider the impacts of climate change to generation and loads. This white paper reviewed 30 IRPs to determine best practices with respect to analyzing and reporting on potential water-based and climate change risks within the integrated resource planning process. Best practices from electric utility IRPs are identified and additional recommendations and considerations are put forth. In recent years, thermal generating facilities have experienced challenges with water availability: a shortage of cooling water, conditions in which incoming cooling water is too warm for optimal operation, and/or water discharge temperatures exceeding permit limits. S&P Global Market Intelligence recently reported on a study that identified for the year 2030, 98.2 gigawatts (GW) of coal capacity at risk due to water stress. Climate change effects on hydrological cycles may adjust the timing, temperature, and volume of water availability for thermal electric cooling and for hydropower generation, which could further exacerbate the frequency and duration of operational constraints. Climate change can also impact the timing and intensity of electric loads that utilities must serve, most notably for heating and cooling.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRSDate not supplied

Simulation of Radiation-Induced DNA Damage With the Code RITRACKS

INTRODUCTION DNA damage is one of the most physiologically important effects of ionizing radiation. Clustered DNA damage events, like double-strand breaks (DSBs), have the most notable biological consequences. DNA damage types depend on both the track structure of the radiation and the spatial organization of the DNA. High linear energy transfer (LET) charged nuclei, found in galactic cosmic rays (GCR), are known to produce large numbers of complex DNA damage events. The human genome is packaged into chromatin, which can take on locus-dependent and cell type-dependent spatial conformations that correspond to epigenetic states, such as more open, extended structures in transcriptionally active chromatin. These epigenetic differences can affect DNA break patterns in response to ionizing radiation, potentially creating distinct DNA repair and signaling outcomes across the genome in different cells. MATERIAL AND METHODS The code RITRACKS (Relativistic Ion Tracks), which simulates stochastic radiation track structures and radiation chemistry, was used to model damage on isolated and histone-bound DNA by various types of ions and photons. The changes made to the code to perform radiation-induced DNA damage, and simulation results on single nucleosomes are given in our recent paper. In this work, the DNA building capabilities of RITRACKS have been extended to simulate more complex DNA structures build on the coarse-grain simulation framework meso-WLCsim. This code can sample generic chromatin fiber conformation ensembles based on the geometry of nucleosomes and mechanical properties of DNA. Using RITRACKS, we simulated the fragment length distributions (FLD) of irradiated DNA structures built using the chromatin conformations of WLCsim and obtained results representative of those obtained with Radiation-Induced Correlated Cleavage with sequencing (RICC-Seq) experiments [6]. We have also performed Fe ion and photon irradiations of K562, IMR90, BJ and RPE-1 cells at NSRL to experimentally validate results. Sample processing and data analysis are in progress and any available preliminary results will be discussed. DISCUSSION The recent updates in the code RITRACKS allow the calculation of several quantities such as the DNA damage yield and the FLD. This approach can be used to model epigenetic state-specific chromatin structure parameters to leverage the epigenetic state data available for many human cell types to infer relative DNA damage sensitivity among genomic loci.

I Plante↗
DOE OSTI2023

Reassessing long-standing meteorological records: an example using the national hottest day in Ireland

This analysis highlights the potential value in reanalysing early national meteorological records from around the world. These were oftentimes measured via techniques that preceded standardisation of instrumentation and methods of observation and thus could be subject to considerable biases and uncertainties. This analysis uses the techniques pioneered by WMO record assessment teams. The highest currently recognised air temperature (33.3 °C) ever recorded in the Republic of Ireland was logged at Kilkenny Castle in 1887. The original observational record however no longer exists. Given that Ireland is now the only country in Europe to have a national heat record that was set in the 19th century, a reassessment of the verity of this record is both timely and valuable. The present analysis undertakes a fundamental reassessment of the plausibility of the 1887 temperature record using methods similar to those used to assess various weather extremes under WMO auspices over recent years. Specifically, we undertake an inter-station reassessment using sparse available records and make recourse to the new and improved 20CRv3 sparse-input reanalysis product. Neither surrounding available stations nor the reanalysis offer substantive support for the Kilkenny record of 33.3 °C being correct. Moreover, recent data rescue efforts have uncovered several earlier extreme values, one of which exceeds the Kilkenny value (33.5 °C on 16 July 1876 recorded at the Phoenix Park). However, the sparsity of early observational networks, a distinct lack of synoptic support from 20CRv3 for many of the extreme heat values, and the fact that these measurements were obtained using non-standard exposures lead us to conclude that there is grossly insufficient evidence to support any of these 19th century extremes as robust national heat record candidates. Data from the early 20th century onwards benefit from a denser network of stations undertaking measurements in a more standardised manner, many under the direct auspices of Met Éireann and its predecessors, adhering to WMO guidance and protocols. This enables more robust cross-checking of records. We argue that the Met Éireann-recognised 20th century heat record from Boora in 1976 is verified as the most plausible robust national temperature record based upon the synoptic situation and comparisons with nearby neighbouring stations. This measurement of 32.5°C thus likely constitutes the highest reliably recorded temperature measurement in the Republic of Ireland. Ultimately, the formal decision on any reassessment and reassignment of the national record rests with the national meteorological service, Met Éireann.

15 GEOTHERMAL ENERGY↗