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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 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
NASA NTRS2000

STS-106 Crew Activity Report/Flight Day 11 Highlights

Live animation of the Space Shuttle Atlantis slowly pulling away from the International Space Station is presented. Pilot Scott Altman flew the Atlantis away from the I.S.S. and describes this process. A live view of Commander Terry Wilcutt, Pilot Scott Altman and Mission Specialists Ed Lu, Rick Mastracchio, Dan Burbank, Yuri Malenchenko and Boris Morukov aboard the Space Shuttle Atlantis is shown. The astronauts then answered questions inside the SpaceHab module about the living conditions aboard the I.S.S. and preparations that were made to the I.S.S. for the next crew to arrive.

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NASA NTRS1992

STS-50 Countdown Status

George Diller of the NASA Public Affairs Office introduces Mike Leinbach, NASA Shuttle Test Director, Russ Lunnen, Kennedy Space Center (KSC) USML Payload Manager, and Ed Priselac, U.S. Airforce/KSC Weather Officer to give a briefing on the countdown status for STS-50. Leinbach gives an overview of when certain tests are run and what problems are encountered. Lunnen outlines the payload activities for the shuttle. Priselac describes the current weather as well as the conditions needed for launch. They also take questions from the press.

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NASA NTRS2000

STS-97 Countdown Status

Joel Wells, NASA Public Affairs, introduces Steve Altemus, NASA Test Director, David Flowers, P-6 Truss Integration Engineer, and Ed Priselac, Shuttle Weather Officer. Mr. Altemus describes the successful countdown thus far, and some of the prelaunch activities. Mr. Flowers gives an overview of the P-6 Truss and its role on the International Space Station (ISS). Mr. Priselac gives a forecast for good launching weather. The men then answer questions from the press.

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NASA NTRS2000

STS-97 Countdown Status

George Diller, NASA Public Affairs, introduces Jeff Spaulding, NASA Test Director, David Flowers, P-6 Truss Integration Engineer, and Ed Priselac, Shuttle Weather Officer. Mr. Spaulding discusses the Shuttle status, successful countdown, and preflight preparations. Mr. Priselac describes a good weather forecast for the upcoming STS-97 Endeavour launch. The men then answer questions from the press.

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NASA NTRS2000

STS-106 Countdown Status Briefing

George Diller, NASA Public Affairs, introduces Jeff Spaulding, NASA Test Director, Scott Higginbotham, KSC Payload Manager, and Ed Priselac, Shuttle Weather Officer. Mr. Spaulding discusses the successful countdown thus far and some of the prelaunch activities. Mr. Higginbotham describes the stow operations and possible changes in the payload configuration. Mr. Priselac forecasts good weather for the upcoming launch. The men then answer questions from the press.

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NASA NTRS2000

STS-106 Countdown Status Briefing

Joel Wells, NASA Public Affairs, introduces Jeff Spaulding, NASA Test Director, Scott Higgenbotham, Kennedy Space Center Payload Manager, and Ed Priselac, Shuttle Weather Officer, who give an overview of the successful countdown for the STS-106 Atlantis mission thus far. Prelaunch activities and the payload status are described. The weather forecast for the upcoming launch is given. The men then answer questions from the press.

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NASA NTRS2000

STS-106 Countdown Status Briefing

George Diller, NASA Public Affairs, introduces Steve Altemus, NASA Test Director, Scott Higgenbotham, Kennedy Space Center Payload Manager, and Ed Priselac, Shuttle Weather Officer, who give an overview of the successful countdown for the STS-106 Atlantis mission thus far. Prelaunch activities are described, such as the engine preparations, the communications systems power up, final flight close outs, and payload status. The weather forecast for the upcoming launch is given. The men then answer questions from the press.

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NASA NTRS1992

STS-53 Countdown Status Briefing

George Diller, NASA Public Affairs, introduces Mike Leinbach, Shuttle Test Director, and Ed Prisella, Shuttle Weather Officer, USAF. They give a summary of the countdown for the launch of STS-53 Discovery and information on the weather for the launch time. They then answer questions from the press.

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NASA NTRS2001

CTE Measurements of Carbon Fibers in ESEM

The strong appeal of carbon fiber reinforced ceramic matrix and carbon-carbon composites arises from their promising high temperature performance within laboratory-simulated nozzle, leading edge and combustor environments. The main drawback in these systems are two fold; namely oxidation affinity and CTE mismatch. To date the emphasis has been on axial CTE mismatch with the push on estimating (component) laminate level data. However, in heterogeneous and anisotropic systems, all failure mechanisms are at micro or nano scales. This paper will report plans and progress on single carbon fibers efforts in order to develop its temperature dependent, anisotropic thermophysical and thermomechanical properties using combination of x-ray spectroscopy and environmental scanning electron microscopy to capture circumferential expansion from 20-900 C in within the SEM chamber. Surface roughness measurements were also determined. Crystallinity was also determined by the quality of the electron diffraction (ED) patterns.

Effinger, Michael↗
NASA NTRS2001

STS-102 Countdown Status

George Diller, NASA Public Affairs, introduces Jeff Spaulding, NASA Test Director, Glenn Chin, Leonardo Payload Manager, and Ed Priselac, Shuttle Weather Officer, in this STS-102 prelaunch press conference. Mr. Spaulding gives an overview of the status of the Discovery Orbiter, including the prelaunch procedures (payload inspection and closure, avionics check, and the loading of the onboard cyrogenic tanks), the countdown and built in time holds, launch window, Discovery launch, and the landing. Mr. Chin discusses the payload status, including specifications on the Multi-Purpose Logistics Module, and the hardware contamination inspection. Mr. Priselac describes the weather forecast for the upcoming launch. The men then answer questions from the press.

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NASA NTRS2001

STS-102 Countdown Status Briefing

Joel Wells, NASA Public Affairs, introduces Pete Nickolenko, NASA Test Director, Glenn Chin, Leonardo Mission Manager, and Ed Priselac, Shuttle Weather Officer, in this STS-102 prelaunch press conference. Mr. Nickolenko gives an overview of the countdown and built-in hold times, the launch window, and prelaunch activities (such as activation and checkout of the onboard computer systems, closing the payload bay doors, servicing of the onboard cryogenic cell tanks, main engine tests, and power-up of the ground communications systems). Mr. Chin confirms that the payload is in the final flight configuration and is ready for launch. Mr. Priselac gives the weather forecast for the launch date. The men then answer questions from the press.

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NASA NTRS2001

Oxidation of ZrB2-SiC

In this paper the oxidation behavior of ZrB2-20 vol% SiC is examined. Samples were exposed in stagnant air in a zirconia furnace (Deltech, Inc.) at temperatures of 1327, 1627, and 1927 C for ten ten-minute cycles. Samples were removed from the furnace after one, five, and ten cycles. Oxidized material was characterized by mass change when possible, x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Oxidation kinetics, oxide scale development, and matrix recession were monitored as a function of time and temperature. Oxidation and recession rates of ZrB2 - 20 vol% SiC were adequately modeled by parabolic kinetics. Oxidation rates of this material are rapid, allowing only very short-term application in air or other high oxygen partial pressure environments.

Opila, Elizabeth J.↗
NASA NTRS2001

Characterization of Carbon Nanotubes Grown by Chemical Vapor Deposition

Since the superior properties of multi-wall carbon nanotubes (MWCNT) could improve numerous devices such as electronics and sensors, many efforts have been made in investigating the growth mechanism of MWCNT to synthesize high quality MWCNT. Chemical vapor deposition (CVD) is widely used for MWCNT synthesis, and scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS) are useful methods for analyzing the structure, morphology and composition of MWCNT. Temperature and pressure are two important growth parameters for fabricating carbon nanotubes. In MWCNT growth by CVD, the plasma assisted method is normally used for low temperature growth. However a high temperature environment is required for thermal CVD. A systematic study of temperature and pressure-dependence is very helpful to understanding MWCNT growth. Transition metal particles are commonly used as catalysis in carbon nanotube growth. It is also interesting to know how temperature and pressure affect the interface of carbon species and catalyst particles

Cochrane, J. C.↗
NASA NTRS2001

Progress on BN and Doped-BN Coatings on Woven Fabrics

A novel, multistep process for applying interface coatings to woven structures using a pulsed CVD process is being evaluated. Borazine (B3N3H6), a neat liquid, and several Si precursors are used in the process to produce BN and SiBN coatings on Hi- Nicalon fabrics and preforms. A three variable, two level, full factorial matrix is proposed to define the influence of processing parameters. Coating morphology, uniformity and chemistry are characterized by field emission scanning electron microscopy (FESEM), energy dispersive (EDS) and Auger spectroscopies.

Hurwitz, Frances I.↗
NASA NTRS2000

1300 K Compressive Properties of Directionally Solidified Ni-33Al-33Cr-1Mo

The Ni-33Al-33Cr-1Mo eutectic has been directionally solidified by a modified Bridgeman technique at growth rates ranging from 7.6 to 508 mm/h to produce grain/cellular microstructures, containing alternating plates of NiAl and Cr alloyed with Mo. The grains had sharp boundaries for slower growth rates (< 12.7 mm/h), while faster growth rates (> 25.4 mm/h) lead to cells bounded by intercellular regions. Compressive testing at 1300 K indicated that alloys DS'ed at rates between 25.4 to 254 mm/h possessed the best strengths which exceed that for the as-cast alloy.

Whittenberger, J. Daniel↗
NASA NTRS2000

Characterization of Molybdate Conversion Coatings for Aluminum Alloys by Electrochemical Impedance Spectroscopy

Electrochemical impedance spectroscopy (EIS) was used to investigate the corrosion inhibiting properties of newly developed proprietary molybdate conversion coatings on aluminum alloy 2024-T3 under immersion in aerated 5% (w/w) NaCl. Corrosion potential and EIS measurements were gathered for six formulations of the coating at several immersion times for two weeks. Nyquist as well as Bode plots of the data were obtained. The conversion-coated alloy panels showed an increase in the corrosion potential during the first 24 hours of immersion that later subsided and approached a steady value. Corrosion potential measurements indicated that formulations A, D, and F exhibit a protective effect on aluminum 2024-T3. The EIS spectra of the conversion-coated alloy were characterized by an impedance that is higher than the impedance of the bare alloy at all the immersion times. The low frequency impedance, Z(sub lf) (determined from the value at 0.05 Hz) for the conversion-coated alloy was higher at all the immersion times than that of the bare panel. This indicates improvement of corrosion resistance with addition of the molybdate conversion coating. Scanning electron microscopy (SEM) revealed the presence of cracks in the coating and the presence of cubic crystals believed to be calcium carbonate. Energy dispersive spectroscopy (EDS) of the test panels revealed the presence of high levels of aluminum, oxygen, and calcium but did not detect the presence of molybdenum on the test panels. X-ray photoelectron spectroscopy (XPS) indicated the presence of less than 0.01 atomic percent molybdenum on the surface of the coating.

Calle, Luz Marina↗
NASA NTRS2001

Effects of Minor Alloying Additions on the Microstructure, Toughness, and Creep Strength of Directionally Solidified NiAl-31Cr-3Mo

A study of the effects of small (0.25 to 1.0 at%) fifth element additions to the structure and mechanical properties of directionally solidified (DS) NiAl-31Cr-3Mo has been undertaken. Essentially all the additions changed the as-DS'ed microstructure from lamellar eutectic grains to cells and, in some cases, introduced NiAl dendrites and/or third phases. In general the alloying additions did not improve strength or toughness over that possessed by the base composition; only Hf and, perhaps Ti, gave a minor increase in elevated temperature creep resistance. The lack of improvement in creep properties is probably due to inability to precipitation harden NiAl.

Whittenberger, J. D.↗