Metal membranes play a vital role in hydrogen purification. Defect-free membranes can exhibit effectively infinite selectivity but must also provide high fluxes, resistance to poisoning, long operational lifetimes, and low cost. Alloying offers one route to improve on membranes based on pure metals such as palladium. We show how ab initio calculations and coarse-grained modeling can accurately ...

A number of the papers presented at the International Conference on Magnetism held at the University of Nottingham in September dealt with alloys of the platinum metals. The proceedings will be published shortly by the Institute of Physics and the Physical Society. Papers describing neutron diffraction studies demonstrated the powerfulness of some of the recently developed techniques. Thus G. G...

OBJECTIVES X-ray scanning analytical microscopy (XSAM) makes it possible to analyze small specimens in air without pretreatment. The purpose of this study was to utilize XSAM for the rapid analysis of metallic dental restorations by microsampling. METHODS Six different dental alloys were scratched with brand-new silicone points to obtain metal on the silicone point for compositional analysis....

There seems some underlying technological interest in recent developments (1-9) in palladium alloy systems because of the possibilities of developing palladium alloys with improved characteristics for use as diffusion membranes for hydrogen purification and allied purposes (10). In addition to the important issues of surface kinetics and membrane thickness, other key factors for improved diffus...

Hydrogen absorption b y series of palladium alloys with s e v c d other metals has nou: b p e r i quite c.xtcnsiwIy invesligated with rcjference to systematic alterations o,f pressurrco m p os i t io n o t h e r rrlated thermodynamic factors and 2: a r io us p a r a rn P t e r s . Ilydrogen permeation has b r w i an important area o,f both academic rind technological intercJst with relation, f ...

STATEMENT OF PROBLEM Dental alloys have different mechanical properties compared with enamel. However, few studies have been conducted to determine the effects of the retention forces of clasps when applied on different cast crowns. PURPOSE The purpose of this study was to evaluate the retention forces of cast circumferential clasps made of cobalt-chromium alloy on complete cast crowns made o...

The present work investigates both the diffusivity and permeability of hydrogen (H) in palladium-silver (PdAg) and palladium-gold (PdAu) alloys over a 400-1200 K temperature range for Pd(100-X)M(X), M=Ag or Au and X=0%-48% using density functional theory (DFT) and kinetic Monte Carlo simulations (KMC). DFT has been employed to obtain octahedral (O)-, tetrahedral (T)-, and transition state (TS)-...

PURPOSE The porcelain fused to gold has been widely used as a restoration both with the natural esthetics of the porcelain and durability and marginal fit of metal casting. However, recently, due to the continuous rise in the price of gold, an interest towards materials to replace gold alloy is getting higher. This study compared the bond strength of porcelain to millingable palladium-silver (P...

Applications of polymer electrolyte membrane fuel cells (PEM-FCs) require a continued search for an optimal catalyst with attributes of high activity, durability, low cost, and resistance to negative effects of impurities in the fuel. Platinum-based bimetallic catalyst systems are widely utilized in PEM-FCs because of their good performance in both the cathode and the anode. Alloying with inexp...