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Energy spectra for decaying 2D turbulence in a bounded domain 总被引:1,自引:0,他引:1
We use results derived in the framework of the replica approach to study the liquid-glass thermodynamic transition. The main results are derived without using replicas and applied to the study of the Lennard-Jones binary mixture introduced by Kob and Andersen. We find that there is a phase transition due to the entropy crisis. We compute both analytically and numerically the value of the phase transition point T(K) and the specific heat in the low temperature phase. 相似文献
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Mora JF Van Berkel GJ Enke CG Cole RB Martinez-Sanchez M Fenn JB 《Journal of mass spectrometry : JMS》2000,35(8):939-952
Editorial Comment Last month we presented, as a Special Feature, a set of five articles that constituted a Commentary on the fundamentals and mechanism of electrospray ionization (ESI). These articles produced some lively discussion among the authors on the role of electrochemistry in ESI. Six authors participated in a detailed exchange of views on this topic, the final results of which constitute this month's Special Feature. We particularly hope that younger scientists will find value in this month's Special Feature, not only for the science that it teaches but also what it reveals about the processes by which scientific conclusions are drawn. To a degree, the contributions part the curtains on these processes and show science in action. We sincerely thank the contributors to this discussion. The give and take of intellectual debate is not always easy, and to a remarkable extent this set of authors has maintained good humor and friendships, even when disagreeing strongly on substance. Graham Cooks and Richard Caprioli Copyright 2000 John Wiley & Sons, Ltd. 相似文献
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Van Berkel GJ Quirke JM Adams CL 《Rapid communications in mass spectrometry : RCM》2000,14(10):849-858
A survey of derivatization strategies and prospective derivatization reactions for conversion of simple alkenes and alkynes to 'electrospray-active' species is presented. General synthetic strategies are discussed and illustrative examples of prospective derivatives prepared from model compounds are presented along with their electrospray ionization (ES) mass spectra. The identified derivatives of these neutral, nonpolar analytes are either ionic or are ionizable in solution through Bronsted acid/base chemistry, by Lewis acid/base chemistry, or by chemical or electrochemical electron-transfer chemistry. Once ionized, the derivatives are expected to be amenable to detection by electrospray ionization-mass spectrometry. Derivatives are identified for positive and negative ion analysis of both alkenes and alkynes. Copyright 2000 John Wiley & Sons, Ltd. 相似文献
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Kuijt J García-Ruiz C Stroomberg GJ Marina ML Ariese F Brinkman UA Gooijer C 《Journal of chromatography. A》2001,907(1-2):291-299
The separation of five phenolic polycyclic aromatic hydrocarbon metabolites (hydroxy-PAHs) has been performed by cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC) using a 30 mM borate buffer (pH 9.0) containing 60 mM sodium dodecyl sulfate and varying concentrations of gamma-cyclodextrin (gamma-CD). A concentration of 12.5 mM gamma-CD was found to provide a baseline separation of the five hydroxy-PAHs. We applied conventional fluorescence and laser-induced fluorescence (LIF) detection, using a new, small-size, quadrupled Nd-YAG laser emitting at 266 nm. The best limits of detection, in the low ng/ml range, were achieved using LIF detection. For all analytes, linearity was observed up to ca. 100 ng/ml. As an application, conjugated pyrene metabolites in hepatopancreas samples from the terrestrial isopods Oniscus asellus and Porcellio scaber were separated and detected. Finally, flatfish bile samples from individuals exposed to polluted sediment or crude oil, which were part of an interlaboratory study, were analyzed by CD-MEKC with conventional fluorescence and LIF detection to determine the 1-hydroxypyrene concentrations. 相似文献
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Weiss JM Simon E Stroomberg GJ de Boer R de Boer J van der Linden SC Leonards PE Lamoree MH 《Analytical and bioanalytical chemistry》2011,400(9):3141-3149
Effect-directed analysis has been applied to a river sediment sample of concern to identify the compounds responsible for
the observed effects in an in vitro (anti-)androgenicity assay. For identification after non-target analysis performed on
a high-resolution LTQ-Orbitrap, we developed a de novo identification strategy including physico-chemical parameters derived
from the effect-directed analysis approach. With this identification strategy, we were able to handle the immense amount of
data produced by non-target accurate mass analysis. The effect-directed analysis approach, together with the identification
strategy, led to the successful identification of eight androgen-disrupting compounds belonging to very diverse compound classes:
an oxygenated polyaromatic hydrocarbon, organophosphates, musks, and steroids. This is one of the first studies in the field
of environmental analysis dealing with the difficult task of handling the large amount of data produced from non-target analysis.
The combination of bioassay activity assessment, accurate mass measurement, and the identification and confirmation strategy
is a promising approach for future identification of environmental key toxicants that are not included as priority pollutants
in monitoring programs. 相似文献
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