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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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Module D-PR Fuel Fabrication Preface to the D-Modules

Generic Technical Factors Affecting Fuel Fabrication. Many in-reactor physical, chemical, metallurgical, mechanical, thermodynamic, and nucleonic factors influence the design and functionality of nuclear fuel. Detailed discussion of these technical factors is beyond the scope of this cost-oriented preface document; however, the following three references are suggested for a more comprehensive discussion of fuel design requirements for both commercial and special use (military and remote location) reactors: IAEA-TECDOC-1686 (IAEA 2012), the World Nuclear Association webpage “Nuclear Fuel and its Fabrication (WNA 2020a), and INL/EXT-20-54641 (Mariani 2020). To aid the reader’s understanding of how design affects life cycle costs, a few technical factors are also briefly discussed in the sections below.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2024

Supporting Data: A Four‐Coordinate Pr 4+ Imidophosphorane Complex

Supporting computational data for the publication titled: A. C. Boggiano, S. Roy Chowdhury, M. D. Roy, M. G. Bernbeck, S. M. Greer, B. Vlaisavljevich,* and H. S. La Pierre* “A Four-Coordinate Pr4+ Imidophosphorane Complex" Angew. Chem. Int. Ed., 2024, e202409789. DOI: 10.1002/anie.202409789

Boggiano, Andrew C.↗
NASA NTRS1977

Quiet Clean Short-haul Experimental Engine (QCSEE). Aerodynamic and aeromechanical performance of a 50.8 cm (20 inch) diameter 1.34 PR variable pitch fan with core flow

The fan aerodynamic and aeromechanical performance tests of the quiet clean short haul experimental engine under the wing fan and inlet with a simulated core flow are described. Overall forward mode fan performance is presented at each rotor pitch angle setting with conventional flow pressure ratio efficiency fan maps, distinguishing the performance characteristics of the fan bypass and fan core regions. Effects of off design bypass ratio, hybrid inlet geometry, and tip radial inlet distortion on fan performance are determined. The nonaxisymmetric bypass OGV and pylon configuration is assessed relative to both total pressure loss and induced circumferential flow distortion. Reverse mode performance, obtained by resetting the rotor blades through both the stall pitch and flat pitch directions, is discussed in terms of the conventional flow pressure ratio relationship and its implications upon achievable reverse thrust. Core performance in reverse mode operation is presented in terms of overall recovery levels and radial profiles existing at the simulated core inlet plane. Observations of the starting phenomena associated with the initiation of stable rotor flow during acceleration in the reverse mode are briefly discussed. Aeromechanical response characteristics of the fan blades are presented as a separate appendix, along with a description of the vehicle instrumentation and method of data reduction.

Giffin, R. G.↗
NASA NTRS1996

Thermocapillary Convection in a Low Pr Material Under Simulated Reduced-Gravity Conditions

A liquid bridge of tin was held between two vertical coaxial iron rods 4.5 mm in diameter and 4.6 mm apart. The temperatures at the top and bottom of the liquid bridge were 325 and 240 degrees, respectively. Flow oscillation was detected by a thermocouple in the liquid bridge. The amplitude and frequency of oscillation were around 1.3 degrees C and 5 Hz, respectively.

Tao, Yong X.↗
NASA NTRS1999

STS-93: Crew Arrival and PR Location

The primary objective of the STS-93 mission was to deploy the Advanced X-ray Astrophysical Facility, which had been renamed the Chandra X-ray Observatory in honor of the late Indian-American Nobel Laureate Subrahmanyan Chandrasekhar. The mission was launched at 12:31 on July 23, 1999 onboard the space shuttle Columbia. The mission was led by Commander Eileen Collins. The crew was Pilot Jeff Ashby and Mission Specialists Cady Coleman, Steve Hawley and Michel Tognini from the Centre National d'Etudes Spatiales (CNES). This videotape shows the astronauts arriving at Kennedy and an inspection in the clean room.

Source record↗
NASA NTRS1994

Pr-specific phytochrome phosphorylation in vitro by a protein kinase present in anti-phytochrome maize immunoprecipitates

Protein kinase activity has repeatedly been found to co-purify with the plant photoreceptor phytochrome, suggesting that light signals received by phytochrome may be transduced or modulated through protein phosphorylation. In this study immunoprecipitation techniques were used to characterize protein kinase activity associated with phytochrome from maize (Zea mays L.). A protein kinase that specifically phosphorylated phytochrome was present in washed anti-phytochrome immunoprecipitates of etiolated coleoptile proteins. No other substrate tested was phosphorylated by this kinase. Adding salts or detergents to disrupt low-affinity protein interactions reduced background phosphorylation in immunoprecipitates without affecting phytochrome phosphorylation, indicating that the protein kinase catalytic activity is either intrinsic to the phytochrome molecule or associated with it by high-affinity interactions. Red irradiation (of coleoptiles or extracts) sufficient to approach photoconversion saturation reduced phosphorylation of immunoprecipitated phytochrome. Subsequent far-red irradiation reversed the red-light effect. Phytochrome phosphorylation was stimulated about 10-fold by a co-immunoprecipitated factor. The stimulatory factor was highest in immunoprecipitates when Mg2+ was present in immunoprecipitation reactions but remained in the supernatant in the absence of Mg2+. These observations provide strong support for the hypothesis that phytochrome-associated protein kinase modulates light responses in vivo. Since only phytochrome was found to be phosphorylated, the co-immunoprecipitated protein kinase may function to regulate receptor activity.

NASA Discipline Plant Biology↗