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91.
Cascaded Raman Stokes lasing in an ultrahigh-Q silica microsphere resonator coupled to a tapered fiber is demonstrated and analyzed. With less than 900 microW of pump power near 980 nm, five cascaded Stokes lasing lines are generated. In addition, a threshold power of 56.4 microW for the first-order Stokes lasing is achieved. The Stokes lasing lines exhibit distinct characteristics depending on their order, as predicted by theoretical analysis. 相似文献
92.
Kerry D. Smith Paul J. Szeptycki 《Proceedings of the American Mathematical Society》2000,128(3):903-908
We prove that paranormal spaces of character are -
collectionwise Hausdorff assuming the set-theoretic principle . This gives an affirmative answer to problem 197 in Problems I wish I could solve, by W. S. Watson (Open Problems in Topology (1990), 37-76).
collectionwise Hausdorff assuming the set-theoretic principle . This gives an affirmative answer to problem 197 in Problems I wish I could solve, by W. S. Watson (Open Problems in Topology (1990), 37-76).
93.
94.
Bluck LJ Jones KS Thomas J Liggins J Harding M Bingham SA Coward WA 《Rapid communications in mass spectrometry : RCM》2002,16(24):2249-2254
We have investigated a novel application of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) for the quantitative analysis of the isoflavones in food matrices. Previous methods have been hampered by the lack of analytical standards to introduce early enough in the extraction procedure to allow compensations for losses at all stages of the procedure. In this work we have produced standard materials that can be added at the initial extraction, by intrinsically labelling soya plants by growing them in an atmosphere enriched in the stable isotope of carbon in CO(2). On analysis these plants were shown to contain phytoestrogens at a high (up to 20%) level of enrichment. The dried plant material has been used to estimate the isoflavone concentrations of a set of spiked flours. For daidzein the methodology was shown to produce results comparable to those achieved by GC/MS techniques. The method was less successful for genistein, possibly due to the greater fragility of this compound under the conditions required for the analysis. 相似文献
95.
Luchaco-Cullis CA Mizutani H Murphy KE Hoveyda AH 《Angewandte Chemie (International ed. in English)》2001,40(8):1456-1460
96.
Peter Cass Kerry Pratt Terry Mann Bob Laslett Ezio Rizzardo 《Journal of polymer science. Part A, Polymer chemistry》2001,39(13):2244-2255
The polymerization regulators mesitylene and 1,3,5‐trimethoxybenzene were investigated as suitable substitutes for benzene in the cobalt(II) octanoate/diethylaluminum chloride/water‐catalyzed polymerization of 1,3‐butadiene to high cis‐1,4‐polybutadiene. The propagation rates were reduced by 50% with the inclusion of 18 mM mesitylene or 0.17 mM trimethoxybenzene. Mesitylene was found to be an inefficient polymerization regulator because it reduced the propagation rate by a combination of regulation and destruction of the active catalyst complex. Not only did trimethoxybenzene reduce the propagation rate by effective regulation at low concentration, it also increased the percentage activity of cobalt to 200%, indicating that two polymer chains were propagating simultaneously from each active center. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2244–2255, 2001 相似文献
97.
Michelle Y. Platts Christopher G. BarberJean-Yves Chiva Rachel L. EastwoodDavid R. Fenwick Kerry A. ParadowskiDavid C. Blakemore 《Tetrahedron letters》2011,52(4):512-514
An efficient route to dipyridone acid HIV integrase inhibitors is developed. The key steps include a one-pot three-step formation of the core template (containing one point of structural diversity) followed by a regioselective benzylation and in situ deprotection to afford the title compounds. 相似文献
98.
Martin D. Griffith Justin Leontini Mark C. Thompson Kerry Hourigan 《Journal of Fluids and Structures》2011,27(5-6):855-860
A numerical investigation of the flow past a circular cylinder centred in a two-dimensional channel of varying width is presented. For low Reynolds numbers, the flow is steady. For higher Reynolds numbers, vortices begin to shed periodically from the cylinder. In general, the Strouhal frequency of the shedding vortices increases with blockage ratio. In addition, a two-dimensional instability of the periodic vortex shedding is found, both empirically and by means of a Floquet stability analysis. The instability leads to a beating behaviour in the lift and drag coefficients of the cylinder, which occurs at a Reynolds number higher than the critical Reynolds number for the three-dimensional mode A-type instability, but lower than a Reynolds number for any mode B-type instability. 相似文献
99.
100.
Kim Greis Dr. Eike Mucha Maike Lettow Dr. Daniel A. Thomas Carla Kirschbaum Sooyeon Moon Alonso Pardo-Vargas Prof. Dr. Gert von Helden Prof. Dr. Gerard Meijer Dr. Kerry Gilmore Prof. Dr. Peter H. Seeberger Prof. Dr. Kevin Pagel 《Chemphyschem》2020,21(17):1905-1907
It has been reported that fragments produced by glycosidic bond breakage in mass spectrometry-based experiments can retain a memory of their anomeric configuration, which has major implications for glycan sequencing. Herein, we use cryogenic vibrational spectroscopy and ion mobility-mass spectrometry to study the structure of B-type fragments of protected galactosides. Cationic fragments were generated from glycosyl donors carrying trichloroacetimidate or thioethyl leaving groups of different anomeric configuration. The obtained infrared signatures indicate that the investigated fragments exhibit an identical structure, which suggests that there is no anomeric memory in B-type ions of fully protected monosaccharides. 相似文献