During the fabrication of niobium superconducting radio frequency (SRF) particle accelerator cavities procedures are used that chemically or mechanically remove the passivating surface film of niobium pentoxide (Nb2O5). Removal of this film will expose the underlying niobium metal and allow it to react with the processing environment. If these reactions produce hydrogen at sufficient concentrat...

objective: repair of an indirect restoration is usually preferred over its replacement. this study aimed to evaluate the effect of silane in different surface preparation techniques on the bond strength of direct to indirect composite resin.   methods: for this in vitro experimental study, 48 indirect composite cubes were fabricated, divided into 4 groups of 12 and subjected to the following pr...

Advanced Energy Systems Inc (AES) and Brookhaven National Laboratory (BNL) are currently working on a program to develop a Superconducting Photocathode Electron Gun using an all Nb cavity. The work is being performed as a Phase II SBIR and under a CRADA between AES and BNL. Results of initial efforts have been presented previously [1,2]. This paper will review the progress being made in this pr...

The adsorption/absorption of hydrogen and the adsorption of carbon monoxide by niobium foils, at room temperature, was studied using thermal desorption spectroscopy. Two hydrogen desorption peaks were observed with a maximum at 404 and 471 K. The first hydrogen desorption peak is regarded as hydrogen desorbing from surface sites while the second peak, which represents desorption from surface si...

Niobium is recognized as an important alloying element in a number of wrought precipitation-hardened nickel-base alloys. It is the purpose of this paper to examine the role that niobium plays in these alloys and describe the properties that are achieved as a result of its inclusion in wrought superalloys. In addition to the general alloying characteristics of niobium as described in the technic...