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121.
122.
123.
Moate CP O'Brien MC Dunn JL Bates CA Liu YM Polinger VZ 《Physical review letters》1996,77(21):4362-4365
124.
Gerald Dunn 《K-Theory》1995,9(6):591-605
We show that theK-theory of a Waldhausen categoryC with anA-ring structure is anA ring spectrum. If theA structure onC supports anE
n
structure, so thatBC group completes to ann-fold loop space, thenK (C) is anE
n
ring spectrum. In particular, theK-theory of the category of crossedG-sets,G a finite group, is anE
2 ring spectrum. 相似文献
125.
Performance characteristics of a continuous-wave intracavity optical parametric oscillator are described by use of an experimental arrangement comprising a KTP singly resonant oscillator located within a Ti:sapphire laser cavity and analyzed by use of a steady-state model. Internal and external powers, circulating fields, tuning ranges, spectral bandwidths, and amplitude-stability levels are measured and discussed. The nonresonant idler tunes from 2.53 to 2.87 microm, delivers a maximum output power of approximately 0.4W and displays long-term amplitude-stable operation. The total downconverted power approaches the optimum power coupled out of the Ti:sapphire laser in the absence of frequency conversion. 相似文献
126.
A reinvestigation of the polymerization of styrene by perchloric acid in methylene dichloride at 0° with improved techniques has shown that the polymerizations are not of first order throughout; after the first half-life, the reaction accelerates and the electrical conductivity of the reaction mixture increases concurrently. These phenomena are ascribed to the slow ionization of the propagating polystyrylperchlorate ester to much more rapidly propagating polystyryl ions present in very low concentrations, and in equilibrium with a much larger concentration of non-propagating polystyrylindanyl ions. Our observations, together with those of other authors on the bimodal DP distribution of polystyrenes formed under similar conditions, confirm that the pseudocationic polymerization propagated by the polystyryl perchlorate ester is indeed a distinct form of reaction. 相似文献
127.
Haralampus-Grynaviski NM Lamb LE Simon JD Krogmeier JR Dunn RC Pawlak A Rózanowska M Sarna T Burke JM 《Photochemistry and photobiology》2001,74(2):364-368
The emission spectra of single lipofuscin granules are examined using spectrally resolved confocal microscopy and near-field scanning optical microscopy (NSOM). The emission spectrum varies among the granules examined revealing that individual granules are characterized by different distributions of fluorophores. The range of spectra observed is consistent with in vivo spectra of human retinal pigment epithelium cells. NSOM measurements reveal that the shape of the spectrum does not vary with position within the emissive regions of single lipofuscin granules. These results suggest that the relative distribution of fluorophores within the emissive regions of an individual granule is homogeneous on the spatial scale approximately 150 nm. 相似文献
128.
The compilation of the literature on ultrasonic propagation properties of mammalian tissues [J. Acoust. Soc. Am. 64, 423 (1978)] is continued with the addition of 45 papers yielding over 700 lines of parametric data. 相似文献
129.
130.