The use of Short Time on Stream (STOS) transient kinetics to investigate the role of hydrogen in enhancing NOx reduction over silver catalysts

The role of hydrogen in promoting the reduction by ammonia of NOx on silver catalysts has been investigated using a Short Time on Stream (STOS) technique to allow differentiation between potentially reactive intermediates and relatively inactive spectator species. Under these conditions, we have used DRIFTS to identify surface nitrate species that are formed and removed on a timescale of seconds. This is in contrast to nitrate species observed under normal steady-state conditions which can continue to form over many tens of minutes. Since this timescale of seconds is very similar to the response rate at which the NH3/NOx to N-2 reaction is accelerated when H-2 is added, or decelerated when H-2 is removed, we conclude that this fast-forming and fast disappearing nitrate species is most probably adsorbed on or close to the active Ag sites. The removal of such a blocking nitrate species from the active sites can explain the effect of H-2 in greatly increasing the rate of the overall de-NOx reaction. 

Short-Sale Constraints and the Pricing of Managerial Skills

We investigate the impact of the absence of short selling on the pricing of managerial skills in the mutual fund industry. In the presence of divergent opinions regarding managerial skills, fund managers can strategically use fees to attract only the most optimistic capital. The recognition of this fee strategy helps explain a set of stylized observations and puzzles in the mutual fund industry, including the underperformance of active funds, the existence of flow convexity, and the negative correlation between gross-of-fee α and fees.

Short report on the 1997 field survey season of the Troina project.

Stoddart, S. and M. C, Private circulation to sponsors. 1997.

Short report on the 1998 field survey and excavation season of the Troina project.

Stoddart, S. and M. C, Private circulation to sponsors. 1998.

Short report on the 1999 field survey and excavation season of the Troina project

Stoddart, S. and M. C,. Private circulation to sponsors. 1999.

Short report on the 2000 field survey and excavation season of the Troina project.

Stoddart, S. and C. Malone, Private circulation to sponsors. 2000.

Short report on the 2001 field survey and excavation season of the Troina project

Stoddart, S. and C. Malone,. Private circulation to sponsors. 2001

Auditory gist: Recognition of very short sounds from timbre cues

Sounds such as the voice or musical instruments can be recognized on the basis of timbre alone. Here, sound recognition was investigated with severely reduced timbre cues. Short snippets of naturally recorded sounds were extracted from a large corpus. Listeners were asked to report a target category (e.g., sung voices) among other sounds (e.g., musical instruments). All sound categories covered the same pitch range, so the task had to be solved on timbre cues alone. The minimum duration for which performance was above chance was found to be short, on the order of a few milliseconds, with the best performance for voice targets. Performance was independent of pitch and was maintained when stimuli contained less than a full waveform cycle. Recognition was not generally better when the sound snippets were time-aligned with the sound onset compared to when they were extracted with a random starting time. Finally, performance did not depend on feedback or training, suggesting that the cues used by listeners in the artificial gating task were similar to those relevant for longer, more familiar sounds. The results show that timbre cues for sound recognition are available at a variety of time scales, including very short ones.

Modeling target bulk heating resulting from ultra-intense short pulse laser irradiation of solid density targets

Isochoric heating of solid-density matter up to a few tens of eV is of interest for investigating astrophysical or inertial fusion scenarios. Such ultra-fast heating can be achieved via the energy deposition of short-pulse laser generated electrons. Here, we report on experimental measurements of this process by means of time-and space-resolved optical interferometry. Our results are found in reasonable agreement with a simple numerical model of fast electron-induced heating. (C) 2013 AIP Publishing LLC.