2,090 research outputs found

    Synthesis of β,β-Disubstituted Styrenes via Trimethylsilyl Trifluoromethanesulfonate-Promoted Aldehyde-Aldehyde Aldol Addition-Deformylative Elimination.

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    In the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) and 2,6-lutidine, α,α-disubstituted aldehydes condense with electron-rich aromatic aldehydes to yield β, β- disubstituted styrenes. More electron-rich aromatic aldehydes react more rapidly and in higher yield. Preliminary results suggest that the reaction may proceed via the ionization and formal deformylation of an aldol intermediate

    Achieving very long lifetimes in optical lattices with pulsed cooling

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    We have realized a one dimensional optical lattice for individual atoms with a lifetime >300 s, which is 5 times longer than previously reported. In order to achieve this long lifetime, it is necessary to laser cool the at-oms briefly every 20 s to overcome heating due to technical fluctuations in the trapping potential. Without cooling, we observe negligible atom loss within the first 20 s followed by an exponential decay with a 62 s time constant. We obtain quantitative agreement with the measured fluctuations of the trapping potential and the corresponding theoretical heating rates.Comment: 4 pages, 5 figure

    Evaluating User Satisfaction and Organisational Benefits of Electronic Medication Management System in an Australian Hospital

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    In this conceptual paper, we speculate on the possibility that a PhD by Artefact and Exegesis (A&E) may be legitimate in the Information Systems (IS) discipline. Research, as creative process and product with the intention of yielding new knowledge, takes many forms across the spectrum of academic disciplines. Other disciplines, particularly in the humanities’ fields of arts and design, have artefacts as a discrete part of their PhD product accompanied by an exegesis of one form or another. It may be that some research in the IS discipline lends itself to the A&E approach. This paper considers A&E PhDs in Humanities and how practice-based research is presented. We explore how A&E might apply to IS research, through comparison with the design science approach. We suggest tentative impacts on candidates, supervisors and examiners then conclude with the issues and open questions raised by our investigations
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