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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 1,261 records · Page 70

All sources NASA NTRS DOE OSTI

NASA NTRS1981

Multiwall TPS: An emerging concept

The transformation of a titanium multiwall thermal protection system from a conceptual design to a working reality is described. The thermal and structural performance of the basic multiwall concept is analyzed. Radiant heat, wind tunnel, vibration, acoustic, and lightning strike tests are used to verify the performance of multiwall tiles under representative operating conditions. Flat, all titanium multiwall configurations limited to temperature below 810 K are discussed. Curved surface, higher temperature versions of the multiwall are considered. Preliminary mass estimates for advanced multiwall concepts are presented.

Shideler, J. L.↗

NASA NTRS1989

Robotic Tool For Tightening And Cutting

Robot end effector designed for tightening tube couplers and for cutting tubes. Tool operable by simple movements and thus manipulated by technician wearing heavy protective clothing. Operates on principle of worm and pinion gear. Intended for use in building structures in space, end effector also used as hand tool for assembling truss structures for terrestrial buildings, tents, and oil rigs. Also used in place of pipe wrench in plumbing work.

Cooney, Earl T.↗

NASA NTRS1990

The physiological cost of wearing the propellant handler's ensemble at the Kennedy Space Center

The potential for exposure to toxins used in the propulsion systems of spacecraft dictates the use of a whole body protective suit, the Propellant Handler's Ensemble (PHE) during preflight preparation and launching. The weight, structure, and operating parameters of the PHE may be expected to have a significant impact upon the metabolic, cardiovascular, and thermal responses of the user, especially during ambient temperature extremes and high workload situations. Four male subjects participated in tests in -7, 23, and 43 C (20, 74, and 110 F) environments in two versions of the PHE, the autonomous backpack (BP) and the hoseline (HL) supplied configuration. Measurements included heart rate (HR) rectal temperature, four skin temperatures, oxygen (O2), and carbon dioxide (CO2) in the helmet area, interior suit temperature, and suit pressure. Exercise metabolism was estimated from HR, PHE weight, and treadmill speed and grade. The HR responses between each PHE configuration were not statistically different. As a percentage of HR maximum, the mean values were 79 percent (COLD), 84 percent (LAB), and 90 percent (HOT). Helmet O2 and CO2 levels were correlated with percent HR max (P less than 0.001). Rectal temperatures were similar for each PHE configuration, except in the HOT exposure where the BP version exceeded the HL configuration (P less than 0.05). In nearly every instance the HR was driven to moderately high levels, the supplied respiratory gases were not optimum, and thermal adversity was a primary stressor. Our findings suggest that medical and physical fitness standards, along with operational restrictions, should be imposed upon PHE users to avoid situations that could adversely affect the worker.

Schonfeld, Brian R.↗

NASA NTRS1990

A silicon micromachined piezoresistive accelerometer for health and condition monitoring

Silicon micromachining etching techniques were utilized to batch-fabricate hundreds of general purpose microaccelerometers on a single silicon substrate. Piezoresistive sensing elements were aligned to the back-side patterns using an IR mask aligner and then diffused into the areas of maximum stress. Capping of the two-arm cantilever beam structure was achieved using a combination of electrostatic bonding and low temperature glass films. Overrange protection, critical damping, and overall protection from the outside environment are achieved by controlling the cavity depths of the top and bottom covers. Temperature compensation, amplification, and filtering are performed by a companion LSI chip that is interfaced to the accelerometer by conventional wire-bonding techniques.

Walsh, Kevin M.↗

NASA NTRS2000

Composite Tank Development

This paper presents viewgraphs on composite tank development. There is a need for oxidizer tanks and reliable, lightweight fuel. The need for cost-effective and scalable manufacturing is also evident. In order to achieve these goals, tooling methods for tank development must be applied, methods for producing easily adaptable and scalable vessel liners must be developed, insulation layer or protective barriers for containers must be manufactured, and an appropriate fiber/resin system for composite overwrap structures must be identified.

DeLay, Thomas K.↗

NASA NTRS2001

Integrated Power Source Grant

Traditional spacecraft power systems incorporate a solar array energy source, an energy storage element (battery), and battery charge control and bus voltage regulation electronics to provide continuous electrical power for spacecraft systems and instruments. Dedicated power conditioning components provide limited fault isolation between systems and instruments, while a centralized power-switching unit provides spacecraft load control. Battery undervoltage conditions are detected by the spacecraft processor, which removes fault conditions and non-critical loads before permanent battery damage can occur. Cost effective operation of a micro-sat constellation requires a fault tolerant spacecraft architecture that minimizes on-orbit operational costs by permitting autonomous reconfiguration in response to unexpected fault conditions. A new micro-sat power system architecture that enhances spacecraft fault tolerance and improves power system survivability by continuously managing the battery charge and discharge processes on a cell-by-cell basis has been developed. This architecture is based on the Integrated Power Source (US patent 5644207), which integrates dual junction solar cells, Lithium Ion battery cells, and processor based charge control electronics into a structural panel that can be deployed or used to form a portion of the outer shell of a micro-spacecraft. The first generation Integrated Power Source is configured as a one inch thick panel in which prismatic Lithium Ion battery cells are arranged in a 3x7 matrix (26VDC) and a 3x1 matrix (3.7VDC) to provide the required output voltages and load currents. A multi-layer structure holds the battery cells, as well as the thermal insulators that are necessary to protect the Lithium Ion battery cells from the extreme temperatures of the solar cell layer. Independent thermal radiators, located on the back of the panel, are dedicated to the solar cell array, the electronics, and the battery cell array. In deployed panel applications, these radiators maintain the battery cells in an appropriate operational temperature range.

Source record↗

NASA NTRS2002

Systematic Underutilization of Glutamine In Thermophile Proteins

Rapid racemization above 100 C of L-amino acids to Domino acids, as well as deamidation, is probably a hazard for high temperature life. For example, the half-life of some asparaginyl peptides can be as short as 10 minutes at 100 C. High temperature organisms could protect themselves by reducing usage of amino acids that are easily racemized/deamidazed, by having a rapid rate of protein turnover which requires energy, or by adapting special cis-peptide conformations. We have searched eight completely sequenced thermophile genomes, and compare them to mesophile genomes, in order to identify underutilized amino acids. To our surprise, asparagine, the most unstable amino acid to deamidation, is used at about the same level in thermophile proteins in comparison to mesophiles whereas it is the second most unstable amino acid, glutamine, that is underutilized in all of eight thermophile species. Glutamines are present at 2% level in a typical thermophile protein, instead of 4% in mesophile. We argue that it is easier to protect asparagines from deamidation by cis-peptide conformations. We discuss statistical as well as structural evidence in support of our conclusions.

Liang, Shoudan↗

NASA NTRS2005

Project Integration Architecture: Distributed Lock Management, Deadlock Detection, and Set Iteration

The migration of the Project Integration Architecture (PIA) to the distributed object environment of the Common Object Request Broker Architecture (CORBA) brings with it the nearly unavoidable requirements of multiaccessor, asynchronous operations. In order to maintain the integrity of data structures in such an environment, it is necessary to provide a locking mechanism capable of protecting the complex operations typical of the PIA architecture. This paper reports on the implementation of a locking mechanism to treat that need. Additionally, the ancillary features necessary to make the distributed lock mechanism work are discussed.

Jones, William Henry↗

NASA NTRS2011

Use of Smoothed Measured Winds to Predict and Assess Launch Environments

This paper describes an approach which was used to predict Ares I-X launch vehicle structural airloads and controllability prior to launch. This prediction along with the proper application of protection for variations in key environment and trajectory parameters was used to predict the potential for the launch trajectory to stay within the integrated vehicle certification envelopes. This data was applied by the launch team as a key element of the launch day go/no-go recommendation. NASA s Space Shuttle and the heavy lift versions of the Evolved Expendable Launch Vehicles assessments require the use of a high fidelity wind measurement which limits the number of wind measurement sources which can be used for a pre-launch go/no-go assessment. The approach described in this paper has the potential to allow the pre-launch assessment team to use wind measurements from a number of additional sources which will enhance launch availability and also has the potential to improve mission assurance and enhance safety

Cordova, Henry S.↗

NASA NTRS2015

High Kinetic Energy Penetrator Shielding and High Wear Resistance Materials Fabricated with Boron Nitride Nanotubes (BNNTS) and BNNT Polymer Composites

Boron nitride nanotubes (BNNTs), boron nitride nanoparticles (BNNPs), carbon nanotubes (CNTs), graphites, or combinations, are incorporated into matrices of polymer, ceramic or metals. Fibers, yarns, and woven or nonwoven mats of BNNTs are used as toughening layers in penetration resistant materials to maximize energy absorption and/or high hardness layers to rebound or deform penetrators. They can be also used as reinforcing inclusions combining with other polymer matrices to create composite layers like typical reinforcing fibers such as Kevlar.RTM., Spectra.RTM., ceramics and metals. Enhanced wear resistance and usage time are achieved by adding boron nitride nanomaterials, increasing hardness and toughness. Such materials can be used in high temperature environments since the oxidation temperature of BNNTs exceeds 800.degree. C. in air. Boron nitride based composites are useful as strong structural materials for anti-micrometeorite layers for spacecraft and space suits, ultra strong tethers, protective gear, vehicles, helmets, shields and safety suits/helmets for industry.

Kang, Jin Ho↗

NASA NTRS2016

Mobile Launch Platform Vehicle Assembly Building Area (SWMU 056) Hot Spot 3 Bioremediation Interim Measures Work Plan, Kennedy Space Center, Florida

This Interim Measures Work Plan (IMWP) presents an approach and design for the remediation of chlorinated volatile organic compound (CVOC) groundwater impacts using bioremediation (biostimulation and bioaugmentation) in Hot Spot 3, which is defined by the area where CVOC (trichloroethene [TCE], cis-1,2-dichloroethene [cDCE], and vinyl chloride [VC]) concentrations are greater than 10 times their respective Florida Department of Environmental Protection (FDEP) Natural Attenuation Default Concentration (NADC) [10xNADC] near the western Mobile Launch Platform (MLP) structure. The IM treatment area is the Hot Spot 3 area, which is approximately 0.07 acres and extends from approximately 6 to 22 and 41 to 55 feet below land surface (ft BLS). Within Hot Spot 3, a source zone (SZ; area with TCE concentrations greater than 1% solubility [11,000 micrograms per liter (micrograms/L)]) was delineated and is approximately 0.02 acres and extends from approximately 6 to 16 and 41 to 50 ft BLS.

MLPV↗

NASA NTRS2016

Preparation of Morpheus Vehicle for Vacuum Environment Testing

The main objective for this summer 2016 tour was to prepare the Morpheus vehicle for its upcoming test inside Plum Brook's vacuum chamber at NASA John H. Glenn Research Center. My contributions towards this project were mostly analytical in nature, providing numerical models to validate test data, generating computer aided analyses for the structure support of the vehicle's engine, and designing a vacuum can that is to protect the high speed camera used during testing. Furthermore, I was also tasked with designing a tank toroidal spray bar system.

Sandoval, Armando↗

NASA NTRS2018

High Kinetic Energy Penetrator Shielding and High Wear Resistance Materials Fabricated with Boron Nitride Nanotubes (BNNTS) and BNNT Polymer Composites

Boron nitride nanotubes (BNNTs), boron nitride nanoparticles (BNNPs), carbon nontubes (CNTs), graphites, or their combinations, are incorporated into matrices of polymer, ceramic or metals. Fibers, yarns, and woven or nonwoven mates of BNNTs are uses as toughening layers in penetration resistant materials to maximize energy absorption and/or high hardness layers to rebound or deform penetrators. They can be also uses as reinforcing inclusions combining with other polymer matrices to create composite layer like typical reinforcing fibers such as Kevlar (Registered Trademark), Spectra (Registered Trademark) ceramics and metals. Enhanced wear resistance and prolonged usage time, even under harsh conditions, are achieved by adding boron nitride nanomaterials because both hardness and toughness are increased. Such materials can be used in high temperature environments since the oxidation temperature of BNNTs exceeds 800 C in air. Boron nitride based composite materials are useful as strong structural materials for anti-micrometeorite layers for spacecraft and space suits, ultra strong tethers, protective gear for the human body as well as for vehicles, helmets, shields and safety suits/helmets for industry.

Kang, Jin Ho↗

NASA NTRS2001

Biology of bone and how it orchestrates the form and function of the skeleton

The principal role of the skeleton is to provide structural support for the body. While the skeleton also serves as the body's mineral reservoir, the mineralized structure is the very basis of posture, opposes muscular contraction resulting in motion, withstands functional load bearing, and protects internal organs. Although the mass and morphology of the skeleton is defined, to some extent, by genetic determinants, it is the tissue's ability to remodel--the local resorption and formation of bone--which is responsible for achieving this intricate balance between competing responsibilities. The aim of this review is to address bone's form-function relationship, beginning with extensive research in the musculoskeletal disciplines, and focusing on several recent cellular and molecular discoveries which help understand the complex interdependence of bone cells, growth factors, physical stimuli, metabolic demands, and structural responsibilities. With a clinical and spine-oriented audience in mind, the principles of bone cell and molecular biology and physiology are presented, and an attempt has been made to incorporate epidemiologic data and therapeutic implications. Bone research remains interdisciplinary by nature, and a deeper understanding of bone biology will ultimately lead to advances in the treatment of diseases and injuries to bone itself.

Review↗

DOE OSTI2025

In Situ MOF Pyrolysis Construction of Hierarchical Porous Co‐Nanoparticles/Carbon Cloth Composites for Enhanced Electromagnetic Wave Shielding and Absorption

The development of high-performance electromagnetic protection materials integrating broadband absorption and effective shielding capabilities is hindered by challenges in simultaneously optimizing multiple electromagnetic properties through conventional material designs. This study pioneers a hierarchical porous Co nanoparticle/carbon cloth (Co/CC) composite via controlled annealing of a Co-MOF precursor on carbon cloth. The Co-MOF served a dual role as both magnetic source and pore-forming agent, enabling in situ generation of uniformly dispersed Co nanoparticles and creation of abundant pores/interfaces on the CC fibers during pyrolysis. This unique architecture synergistically enhanced dielectric loss (via interfacial/dipolar polarization) and magnetic loss (via natural resonance, exchange interactions, and eddy currents), significantly improving impedance matching. The hierarchical pores further functioned as integrated “absorption–reflection” units for efficient electromagnetic energy attenuation. Consequently, the Co/CC composite annealed at 800°C (Co/CC-800) achieves minimum reflection loss (−40.69 dB) and 120% effective absorption bandwidth extension (6.16 GHz) as a filler, and exhibits superior electromagnetic interference shielding effectiveness (46.66 dB) as an integrated component. Significantly, Co/CC-800 demonstrated robust photothermal and electrothermal conversion capabilities, ensuring operational stability in ice-covered and humid harsh environments. This work pioneers a pore-structure-mediated strategy to harmonize dielectric–magnetic synergy, providing a new paradigm for designing advanced multifunctional electromagnetic protection materials.

dielectric‐magnetic synergy↗

DOE OSTI2024

Engineering Small HOMO–LUMO Gaps in Polycyclic Aromatic Hydrocarbons with Topologically Protected States

Topological phases in laterally confined low-dimensional nanographenes have emerged as versatile design tools that can imbue otherwise unremarkable materials with exotic band structures ranging from topological semiconductors and quantum dots to intrinsically metallic bands. The periodic boundary conditions that define the topology of a given lattice have thus far prevented the translation of this technology to the quasi-zero-dimensional (0D) domain of small molecular structures. Here, we describe the synthesis of a polycyclic aromatic hydrocarbon (PAH) featuring two localized zero modes (ZMs) formed by the topological junction interface between a trivial and nontrivial phase within a single molecule. First-principles density functional theory calculations predict a strong hybridization between adjacent ZMs that gives rise to an exceptionally small HOMO–LUMO gap. Scanning tunneling microscopy and spectroscopy corroborate the molecular structure of 9/7/9-double quantum dots and reveal an experimental quasiparticle gap of 0.16 eV, corresponding to a carbon-based small molecule long-wavelength infrared (LWIR) absorber.

77 NANOSCIENCE AND NANOTECHNOLOGY↗

DOE OSTI2021

Biophysical characterization and a roadmap towards the NMR solution structure of G0S2, a key enzyme in non-alcoholic fatty liver disease

In the United States non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease, affecting an estimated 80 to 100 million people. It occurs in every age group, but predominantly in people with risk factors such as obesity and type 2 diabetes. NAFLD is marked by fat accumulation in the liver leading to liver inflammation, which may lead to scarring and irreversible damage progressing to cirrhosis and liver failure. In animal models, genetic ablation of the protein G0S2 leads to alleviation of liver damage and insulin resistance in high fat diets. The research presented in this paper aims to aid in rational based drug design for the treatment of NAFLD by providing a pathway for a solution state NMR structure of G0S2. Here we describe the expression of G0S2 in an E. coli system from two different constructs, both of which are confirmed to be functionally active based on the ability to inhibit the activity of Adipose Triglyceride Lipase. In one of the constructs, preliminary NMR spectroscopy measurements show dominant alpha-helical characteristics as well as resonance assignments on the N-terminus of G0S2, allowing for further NMR work with this protein. Additionally, the characterization of G0S2 oligomers are outlined for both constructs, suggesting that G0S2 may defensively exist in a multimeric state to protect and potentially stabilize the small 104 amino acid protein within the cell. This information presented on the structure of G0S2 will further guide future development in the therapy for NAFLD.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2022

Dual Protective Mechanism of AlPO 4 Coating on High-Nickel Cathode Material for High Energy Density and Long Cycle Life Lithium-Ion Batteries

Cathode material with high nickel content is a promising candidate for the future generation of Li-ion batteries (LIBs). However, severe structural degradation during cycling limits its practical use, especially for electric vehicles. Herein, AlPO 4 nanoparticles were synthesized and then coated onto the surface of a high-nickel layer-structured cathode via a dry coating method. The AlPO 4 nanoparticles coating significantly improved the cycling stability from 69.2% to over 80% capacity retention after 140 cycles. Furthermore, the structure and chemical composition of the AlPO 4 -coated cathode was investigated by XRD, SEM, XPS, and STEM. Compared with the non-coated cathode, we revealed a dual protective mechanism for enhanced cycling stability, where Al doping and Li 3 PO 4 coating play synergistic roles in protecting cathode material through long-term cycling. This work demonstrates a facile and environmentally friendly approach toward improving the performance of high-nickel LIB cathodes, which can be easily scaled up for industrial applications.

25 ENERGY STORAGE↗