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Ruiz, R.

Publications and source records attributed to Ruiz, R..

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2001

Effects of via-conductor geometry in the electromigration failure of Al:Cu wires

Electromigration (EM) experiments conducted using two types of via/plug to conductor alignment indicate a geometrical dependence of electromigration failure in Al:Cu conductors. The resistance vs time curves show distinctive steps when the alignment is parallel. This is explained by a successive loss of conductivity through the plug due to void formation. In the perpendicular via/conductor arrangement, resistance increases by smaller and closely spaced steps. EM experiments without vias, found that the conductor life under stress increases by at least an order of magnitude. Kinetic studies at four temperatures between 180-240 C found activation energies to be 1.0 plus or minus 0.1eV.

Al:Cu accelerated testing electromigration activat↗
NASA NTRS2000

Thin Film Catalyst Layers for Direct Methanol Fuel Cells

One of the primary obstacles to the widespread use of the direct methanol fuel cell (DMFC) is the high cost of the catalyst. Therefore, reducing the catalyst loading well below the current level of 8-12 mg/cm 2 would be important to commercialization. The current methods for preparation of catalyst layers consisting of catalyst, ionomer and sometimes a hydrophobic additive are applied by either painting, spraying, decal transfer or screen printing processes. Sputter deposition is a coating technique widely used in manufacturing and therefore particularly attractive. In this study we have begun to explore sputtering as a method for catalyst deposition. Present experiments focus on Pt-Ru catalyst layers for the anode.

Witham, C. K.↗
NASA NTRS1996

Opportunities for Low Temperature Research Aboard the Space Station

A cryogenic Space Station facility is being developed by the Jet Propulsion Laboratory and industrial partners to support the microgravity needs of the international scientific community....Capabilities, conceptual designs and development plans for the facility will be discussed along with a summary of potential near term flight candidate experiments.

Space Station cryogenic microgravity↗
NASA NTRS1996

Low Temperature Microgravity Physics Space Station Facility

A Low Temperature Microgravity Physics Facility under definition for the International Space Station satisfies or exceeds the recommendations of the Science Community and NASA Advisory Boards. LTMPF supports long term multiple experiment modules at low cost with frequent flight opportunities as often as every 20 months.

cryogenic↗