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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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A systematic analysis of Cu-based membrane-electrode assemblies for CO 2 reduction through multiphysics simulation
A multiphysics model is presented to study potential losses in Cu-MEAs and how various physical phenomena impact the product distribution of CO 2 reduction.
Impact of backbone composition on homopolymer dynamics and brush block copolymer self-assembly
Abstract not provided
Nanocomposite tectons as unifying systems for nanoparticle assembly
We show how nanocomposite tectons (NCTs) provide a unification of the two most successful assembly strategies: DNA and solvent evaporation.
Thermal conductivity in self-assembled CoFe 2 O 4 /BiFeO 3 vertical nanocomposite films
The thermal conductivity of self-assembled nanocomposite oxide films consisting of cobalt ferrite (CFO) spinel pillars grown within a single-crystal bismuth ferrite (BFO) perovskite matrix is described as a function of the volume fraction of the spinel. Single phase BFO and CFO had cross-plane thermal conductivities of 1.32 W m –1 K –1 and 3.94 W m –1 K –1 , respectively, and the thermal conductivity of the nanocomposites increased with the CFO volume fraction within this range. A small increase (~5%) in thermal conductivity for the pure CFO phase in the AC-demagnetized state was observed, suggesting possible magnon contributions. As a result, steady state gray-medium based variance-reduced Monte Carlo simulations show consistent trends with experimental data on the dependence of thermal conductivity with the CFO volume fraction.
Parametric evaluation of ducted fuel injection in an optically accessible mixing-controlled compression-ignition engine with two- and four-duct assemblies
Ducted fuel injection (DFI) is a strategy to improve fuel/charge-gas mixing in direct-injection compression-ignition engines. DFI involves injecting fuel along the axis of a small tube in the combustion chamber, which promotes the formation of locally leaner mixtures in the autoignition zone relative to conventional diesel combustion. Previous work has demonstrated that DFI is effective at curtailing engine-out soot emissions across a wide range of operating conditions. This study extends previous investigations, presenting engine-out emissions and efficiency trends between ducted two-orifice and ducted four-orifice injector tip configurations. For each configuration, parameters investigated include injection pressure, injection duration, intake manifold pressure, intake manifold temperature, start of combustion timing, and intake-oxygen mole fraction. For both configurations and across all parameters, DFI reduced engine-out soot emissions compared to conventional diesel combustion, with little effect on other emissions and engine efficiency. Emissions trends for both configurations were qualitatively the same across the parameters investigated. The four-duct configuration had higher thermal efficiency and indicated-specific engine-out nitrogen oxide emissions but lower indicated-specific engine-out hydrocarbon and carbon monoxide emissions than the two-duct assembly. Both configurations achieved indicated-specific engine-out emissions for both soot and nitrogen oxides that comply with current on- and off-road heavy-duty regulations in the United States without exhaust-gas aftertreatment at an intake-oxygen mole fraction of 12%. High-speed in-cylinder imaging of natural soot luminosity shows that some conditions include a second soot-production phase late in the cycle. The probability of these late-cycle events is sensitive to both the number of ducted sprays and the operating conditions.
Resonant X-ray scattering of biological assemblies
Understanding the relationship between structure and function for biological assemblies can guide identification of new therapeutics, design of biomaterials, and development of biotechnological processes. Resonant X-ray scattering provides a chemically-specific approach to characterize complex biological structures based on anomalous or resonant scattering from a specific element or chemical moiety. Anomalous or resonant diffraction can provide structural details with high atomic resolution, while resonant X-ray scattering can provide structural details with lower resolution through tender or soft X-rays. Furthermore, we review applications, challenges, and opportunities for resonant X-ray scattering in the field of structural biology.
THE SUCESSFUL APPLICATION OF A REPEATED TEST-TO-FAILURE PROGRAM ON SERGEANT MISSILE ASSEMBLIES. PART I. THE DESIGN, APPLICATION, AND RESULTS OF THE COMBINED OPERATING TEMPERATURE VIBRATION TEST FOR MISSILE ASSEMBLIES RELIABILITY. PART II. STATISTICAL TECHNIQUES APPLIED TO THE SERGEANT REPEATED TEST-TO-FAILURE PROGRAM. PART III. CONCLUSIONS AND RECOMMENDATIONS
Reliability of sergeant missile assemblies - application of test-to-failure program
Fabrication, assembly and test of solar simulator optical train assemblies Final report
Fabrication, assembly, and quality control of solar simulator optical train nickel mirrors
Biological Monitoring of the Capsule Mechanical Training Model During Assembly in the Sterilization Assembly Development Laboratory
Microbial burden sterilization assembly procedure development using rigorous monitoring program
Rotary solenoid shutter drive assembly and rotary inertia damper and stop plate assembly
A camera shutter assembly composed of a pair of superposed opaque planar shutter blades, each having an aperture and being arranged for reciprocal linear movement is disclosed. A pair of rotary solenoids, each connected to one of the blades by a linkage and arranged to be actuated separately at a predetermined interval is provided. An inertia damper and stop plate is built into each solenoid to prevent rebound.
Mariner Jupiter/Saturn LCSSE thruster/valve assembly and injection propulsion unit rocket engine assemblies: 0.2-lbf T/VA development and margin limit test report
Thruster valve assemblies (T/VA's) were subjected to the development test program for the combined JPL Low-Cost Standardized Spacecraft Equipment (LCSSE) and Mariner Jupiter/Saturn '77 spacecraft (MJS) programs. The development test program was designed to achieve the following program goals: (1) demonstrate T/VA design compliance with JPL Specifications, (2) to conduct a complete performance Cf map of the T/VA over the full operating range of environment, (3) demonstrate T/VA life capability and characteristics of life margin for steady-state limit cycle and momentum wheel desaturation duty cycles, (4) verification of structural design capability, and (5) generate a computerized performance model capable of predicting T/VA operation over pressures ranging from 420 to 70 psia, propellant temperatures ranging from 140 F to 40 F, pulse widths of 0.008 to steady-state operation with unlimited duty cycle capability, and finally predict the transient performance associated with reactor heatup during any given duty cycle, start temperature, feed pressure, and propellant temperature conditions.
Mariner Jupiter/Saturn LCSSE thruster/valve assembly and injection propulsion unit rocket engine assemblies: 0.2-lbf T/VA development and margin limit test report, addendum
Capillary tube plugging phenomena on the 0.2-lbf thruster/valve assembly was examined. Vibration tests were conducted in the nozzle up attitude. Failure to fire caused by blockage of the capillary tube by catalyst fines was observed after vibration. Water flushing and previbration hot firing were used to remove the fines.
A Motor Drive Electronics Assembly for Mars Curiosity Rover: An Example of Assembly Qualification for Extreme Environments
In this paper, the technology development and infusion of the motor drive electronics assembly, along with the technology qualification and space qualification, is described and detailed. The process is an example of the qualification methodology for extreme environmen
Glassy embedded solid-state electrode assemblies, solid-state batteries and methods of making electrode assemblies and solid-state batteries
Batteries, component structures and manufacturing methods, in particular including a glassy embedded battery electrode assembly having a composite material structure composed of interpenetrating material components including a porous electroactive network including a solid electroactive material, and a continuous glassy medium including a Li ion conducting sulfide glass, can achieve enhanced power output, reduced charging time and/or improved cycle life.
Predictive Theoretical Framework for Dynamic Control of Bioinspired Hybrid Nanoparticle Self-Assembly
Not Available