979 research outputs found
High temperature cobalt-base alloy Patent
High temperature cobalt-base alloy resistant to corrosion by liquid metals and to sublimation in vacuum environmen
Cobalt-base alloy
A microstructurally stable, high strength cobalt based alloy for use at elevated temperatures to 2125 F was developed. The alloys are particularly directed for use in stators and other low stress components in advanced gas turbines
Advanced alloy design technique: High temperature cobalt base superalloy
Advanced alloy design technique was developed for treating alloys that will have extended life in service at high temperature and intermediate temperatures. Process stabilizes microstructure of the alloy by designing it so that compound identified with embrittlement is eliminated or minimized. Design process is being used to develop both nickel and cobalt-base superalloys
Effect of variations in silicon and iron content on embrittlement of L-605 /HS-25/
Silicon and iron content effects on ductility and tensile strength of cobalt alloy after agin
Nasa developments in cobalt-base superalloys
Chemical, mechanical and physical properties of cobalt-refractory-metal superalloys for high temperature aerospace application
Development of a cobalt-tungsten ferromagnetic, high-temperature, structural alloy
Cobalt-tungsten ferromagnetic, high temperature structural alloy for rotor applications in space power generator
First radius measurements of very low mass stars with the VLTI
e present 4 very low mass stars radii measured with the VLTI using the 2.2
microns VINCI test instrument. The observations were carried out during the
commissioning of the 104-meter-baseline with two 8-meter-telescopes. We measure
angular diameters of 0.7-1.5 mas with accuracies of 0.04-0.11 mas, and for
spectral type ranging from M0V to M5.5V. We determine an empirical mass-radius
relation for M dwarfs based on all available radius measurements. The observed
relation agrees well with theoretical models at the present accuracy level,
with possible discrepancy around 0.5-0.8 Msolar that needs to be confirmed. In
the near future, dozens of M dwarfs radii will be measured with 0.1-1%
accuracy, with the VLTI, thanks to the improvements expected from the near
infrared instrument AMBER. This will bring strong observational constraints on
both atmosphere and interior physics.Comment: Accepted for publication in Astronomy and Astrophysics Letters, 4
pages, 3 figure
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Consolidated Edison Thorium Reactor-Reactor Vessel Internal Components Design
The design functions and fabrication details for internal components of the CETR are presented and pertinent analytical stress studies are summarized. Functions of the internal components include proper orientation and support for the fuel elements, proper distribution of primary coolant within the reactor vessel, and the establishment of guide channels for the control rods. (J.R.D.
Thermochemistry of Alane Complexes for Hydrogen Storage: A Theoretical and Experimental Comparison
Knowledge of the relative stabilities of alane (AlH3) complexes with electron
donors is essential for identifying hydrogen storage materials for vehicular
applications that can be regenerated by off-board methods; however, almost no
thermodynamic data are available to make this assessment. To fill this gap, we
employed the G4(MP2) method to determine heats of formation, entropies, and
Gibbs free energies of formation for thirty-eight alane complexes with NH3-nRn
(R = Me, Et; n = 0-3), pyridine, pyrazine, triethylenediamine (TEDA),
quinuclidine, OH2-nRn (R = Me, Et; n = 0-2), dioxane, and tetrahydrofuran
(THF). Monomer, bis, and selected dimer complex geometries were considered.
Using these data, we computed the thermodynamics of the key formation and
dehydrogenation reactions that would occur during hydrogen delivery and alane
regeneration, from which trends in complex stability were identified. These
predictions were tested by synthesizing six amine-alane complexes involving
trimethylamine, triethylamine, dimethylethylamine, TEDA, quinuclidine, and
hexamine, and obtaining upper limits of delta G for their formation from
metallic aluminum. Combining these computational and experimental results, we
establish a criterion for complex stability relevant to hydrogen storage that
can be used to assess potential ligands prior to attempting synthesis of the
alane complex. Based on this, we conclude that only a subset of the tertiary
amine complexes considered and none of the ether complexes can be successfully
formed by direct reaction with aluminum and regenerated in an alane-based
hydrogen storage system.Comment: Accepted by the Journal of Physical Chemistry
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