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121.
A. Lucarelli A. Frey R. Yang G. Lüpke F. Grilli T. Haugan G. Levin P. Barnes 《Applied Physics A: Materials Science & Processing》2007,88(4):601-604
Time-resolved magneto-optical imaging measurements show that an ac current enables the vortex matter in YBa2Cu3O7-x thin films to reorganize into two coexisting steady states of driven vortex motion with different characteristics: a quasi-static
disordered glassy state in the sample interior and a dynamic state of plastic motion near the edges. Finite-element calculations
consistent with the critical state model show good agreement with the measured field profiles in the quasi-static state but
predict a larger hysteretic behavior in the dynamic state.
PACS 74.25.Qt; 74.25.Ha; 74.25.Sv; 74.78.Bz 相似文献
122.
123.
Keith D. Barnes Ping Chen Yingyan Chang Robert M. Lewis Christopher M. Manley Nicholas J. Mayhew 《合成通讯》2013,43(1):67-72
A convergent synthesis of indoprofen via a Buchwald coupling approach is reported. Using this methodology, indoprofen and a set of analogs of indoprofen were readily prepared. 相似文献
124.
125.
A. Saifer M. Kornblum S. P. Worden I. B. Rushing I. P. Barnes A. P. Surer M. Farren Greta Hammarsten B. Melichar L. Vsetecka S. A. Poworinskaja Raimonde Duval J. M. Le Goff E. Justin-Mueller G. Haslewood E. King A. T. Cameron J. S. Guthrie F. D. White Th. Findley Regine Kapeller-Adler N. P. Meschkowa Rangier Lafrançaise P. A. Clifford H. J. Wichmann F. Timm E. Komm F. Kiermeier und A. Douglas-Sauermann 《Fresenius' Journal of Analytical Chemistry》1938,115(7-8):296-300
Ohne Zusammenfassung 相似文献
126.
Anne E. Counterman Amy E. Hilderbrand Catherine A. Srebalus Barnes David E. Clemmer 《Journal of the American Society for Mass Spectrometry》2001,12(9):1020-1035
Ion mobility/time-of-flight techniques have been used to examine the onset of aggregation in model systems of Gly-Xxx (where Xxxx = Ala, Asn, Asp, Gln, Glu, His, Leu, Ser, Thr, and Trp) dipeptides. Under the experimental conditions employed, there is evidence that simple binary and quaternary mixtures of these dipeptides produce clusters containing as many as 16 to 75 peptide units (and 1 to 7 charges). In some systems, cluster compositions appear to come about largely from statistical association of peptide units; other dipeptide mixtures (and generally for small clusters) show evidence for nonstatistical behavior which could arise from some differences in gas-phase or solution thermochemistry. The minimum aggregate size appears to be largely determined by the charge state. Average thresholds for aggregate formation in the z = 2, 3, and 4 charge state families occur at m/z ∼500, 660, and 875, respectively. We briefly consider the idea that aggregates formed during electrospray ionization (ESI) may contribute to the background signal observed in the analysis of complex peptide mixtures. 相似文献
127.
We present a theoretical analysis of the noise performance of phase measuring feedback interferometers. We first analyse the operation of this kind of instrument and note that under certain circumstances bistability can occur. The bistable region should be avoided if possible when using feedback interferometry for high-accuracy measurement with low-input powers, as it can give rise to very high-noise levels. We then go on to investigate the effects of shot noise (on the interferometer output signal) and thermal noise (in the feedback loop), and relate these to the phase measurement accuracy of the interferometer. A ‘best-case’ calculation indicates that phase noise of about 0.005λ is possible at input powers in the nanowatt region. In practice, we expect that noise levels will be higher than predicted (particularly at high-input powers) due to the effects of vibration and air turbulence. 相似文献
128.
T. Caspersson Gösta Widström C. C. Lucas E. J. King J. H. W. Lugg H. Barnes R. A. Peters H. Fujiwara E. Kataoka M. X. Sullivan W. C. Hess H. D. Baernstein N. Bulgakow O. Fürth A. Friedrich R. School F. Fromm L. Binet G. Weller Regine Kapeller-Adler Emil Fischer G. Kollmann Mary A. B. Brazier Morner E. Abderhalden O. Kestner Osborne H. D. Dakin E. Schultze K. Spiro P. A. Levene R. H. Aders O. Gerngross W. Deseke W. F. Koelker D. D. van Slyke A. Hynd M. G. Mc Farlane E. Montignie 《Analytical and bioanalytical chemistry》1935,100(1-2):50-60
129.
Bruce A. Barnes 《Proceedings of the American Mathematical Society》2005,133(1):155-162
In this paper, relationships among the concepts, majorization, range inclusion, and factorization, are studied in a general setting for bounded linear operators. Some applications of these concepts are given.