High temperature cobalt-base alloy Patent

High temperature cobalt-base alloy resistant to corrosion by liquid metals and to sublimation in vacuum environmen

A Dissipative Model for Hydrogen Storage: Existence and Regularity Results

We prove global existence of a solution to an initial and boundary value problem for a highly nonlinear PDE system. The problem arises from a thermomechanical dissipative model describing hydrogen storage by use of metal hydrides. In order to treat the model from an analytical point of view, we formulate it as a phase transition phenomenon thanks to the introduction of a suitable phase variable. Continuum mechanics laws lead to an evolutionary problem involving three state variables: the temperature, the phase parameter and the pressure. The problem thus consists of three coupled partial differential equations combined with initial and boundary conditions. Existence and regularity of the solutions are here investigated by means of a time discretization-a priori estimates-passage to the limit procedure joined with compactness and monotonicity arguments

Nasa developments in cobalt-base superalloys

Chemical, mechanical and physical properties of cobalt-refractory-metal superalloys for high temperature aerospace application

Hominin palaeoecology in Late Pliocene Malawi : first insights from isotopes (13C, 18O) in mammal teeth

Carbon-13 and oxygen-18 abundances were measured in large mammal skeletal remains (tooth enamel, dentine and bone) from the Chiwondo Beds in Malawi, which were dated by biostratigraphic correlation to ca. 2.5 million years ago. The biologic isotopic patterns, in particular the difference in carbon-13 abundances between grazers and browsers and the difference in oxygen-18 abundances between semi-aquatic and terrestrial herbivores, were preserved in enamel, but not in dentine and bone. The isotopic results obtained from the skeletal remains from the Chiwondo Beds indicate a dominance of savannah habitats with some trees and shrubs. This environment was more arid than the contemporaneous Ndolanya Beds in Tanzania. The present study confirms that robust australopithecines were able to live in relatively arid environments and were not confined to more mesic environments elsewhere in southern Africa

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

Patient considerations in the treatment of COPD: focus on the new combination inhaler umeclidinium/vilanterol.

Medication adherence among patients with chronic diseases, such as COPD, may be suboptimal, and many factors contribute to this poor adherence. One major factor is the frequency of medication dosing. Once-daily dosing has been shown to be an important variable in medication adherence in chronic diseases, such as COPD. New inhalers that only require once-daily dosing are becoming more widely available. Combination once-daily inhalers that combine any two of the following three agents are now available: 1) a long-acting muscarinic antagonist; 2) a long acting beta2 agonist; and 3) an inhaled corticosteroid. A new once-daily inhaler with both a long-acting muscarinic antagonist, umeclidinium bromide, and a long acting beta2 agonist, vilanterol trifenatate, is now available worldwide for COPD treatment. It provides COPD patients convenience, efficacy, and a very favorable adverse-effects profile. Additional once-daily combination inhalers are available or will soon be available for COPD patients worldwide. The use of once-daily combination inhalers will likely become the standard maintenance management approach in the treatment of COPD because they improve medication adherence

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