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David Briggs was a surface analysis pioneer. Starting in 1970 and continuing throughout his career, Dave used his expertise, vision, and ability to quickly master new surface analysis methods and solve important industrial problems. It certainly helped that he was an outstanding fundraiser in both industrial and academic settings, which ensured he always had an impressive array of the latest, most advanced surface analysis instrumentation at his disposal. He insisted on doing surface analysis correctly, and through his publications, databases, and books, he provided the community with the needed guidelines and methods to do so. In the 1970s, Dave's research was largely focused on X-ray photoelectron spectroscopy (XPS, also known as electron spectroscopy for chemical analysis [ESCA]) characterization of polymers and catalysts. He added secondary ion mass spectrometry (SIMS) to his instrumentation arsenal in the 1980s and provided many of the key, pioneering publications that described how to use this method to characterize polymer surfaces. He also did some of the first surface analysis imaging experiments in the 1980s. In the 1990s, he continued his XPS and SIMS research on polymers and advanced the surface analysis community's ability to properly interpret surface analysis data through databases and advanced data processing methods. Dave continued to publish polymer and catalysis surface analysis papers in the 2000s, but also expanded his surface analysis studies to several other topics. 相似文献
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Manon Catherin Olatz Uranga-Barandiaran Arnaud Brosseau Dr. Rémi Métivier Dr. Gabriel Canard Dr. Anthony D'Aléo Dr. David Casanova Prof. Frédéric Castet Dr. Elena Zaborova Prof. Frédéric Fages 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(17):3818-3828
We describe the synthesis of a series of covalently linked dimers of quadrupolar curcuminoid-BF2 dyes and the detailed investigation of their solvent-dependent spectroscopic and photophysical properties. In solvents of low polarity, intramolecular folding induces the formation of aggregated chromophores, the UV/Vis absorption spectra of which display the optical signature characteristic of weakly-coupled H-aggregates. The extent of folding and, in turn, of ground-state aggregation is strongly dependent on the nature of the flexible linker. Steady-state and time-resolved fluorescence emission spectroscopies show that the Frenkel exciton relaxes into a fluorescent symmetrical excimer state with a long lifetime. Furthermore, our in-depth studies show that a weakly emitting excimer lies on the pathway toward a photocyclomer. Two-dimensional 1H NMR spectroscopy and density functional theory (DFT) allowed the structure of the photoproduct to be established. To our knowledge, this represents the first example of a [2π+2π] photodimerization of the curcuminoid chromophore. 相似文献
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Liam J. R. McGeachie Cameron L. Carpenter-Warren David B. Cordes Michael Bühl Steven J. Gray Guoxiong Hua Alexandra M. Z. Slawin J. Derek Woollins 《无机化学与普通化学杂志》2020,646(22):1795-1798
An improved route to d-block and main group NSO complexes is presented including the synthesis of the first antimony(V) complexes, (Ar3Sb(NSO)2), and copper examples [CuBipy(PPh3)NSO]. The structures of eight complexes are reported. The observed variation in M–N–S bond angles is due to the combination of orbital overlap (ligand-to-metal bonding) and the degree of ionicity of the bonding. 相似文献
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Nonlinear Dynamics - This paper addresses the problem of trajectory tracking control of an underactuated surface vessel moving in a two-dimensional space in the presence of unknown disturbances. In... 相似文献