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111.
Johannes Canisius Andreas Gerold Norbert Krause 《Angewandte Chemie (International ed. in English)》1999,38(11):1644-1646
With a direct kinetic study , activation parameters for the 1,4-cuprate addition to enones (see the Arrhenius plot,▴) and the 1,6-addition to acceptor-substituted enynes (█) were determined for the first time. Both reactions might involve σ copper(III ) species which are formed by oxidative addition of the respective substrate to the cuprate. 相似文献
112.
We have performed a complete enumeration of nonisotopic triples of mutually orthogonal Latin rectangles for . Here we will present a census of such triples, classified by various properties, including the order of the autotopism group of the triple. As part of this, we have also achieved the first enumeration of pairwise orthogonal triples of Youden rectangles. We have also studied orthogonal triples of rectangles which are formed by extending mutually orthogonal triples with nontrivial autotopisms one row at a time, and requiring that the autotopism group is nontrivial in each step. This class includes a triple coming from the projective plane of order 8. Here we find a remarkably symmetrical pair of triples of rectangles, formed by juxtaposing two selected copies of complete sets of mutually orthogonal Latin squares of order 4. 相似文献
113.
Keith Johnston Cecilia Tapia-Siles Bjoern Gerold Michiel Postema Sandy Cochran Alfred Cuschieri Paul Prentice 《Ultrasonics》2014
Single clouds of cavitation bubbles, driven by 254 kHz focused ultrasound at pressure amplitudes in the range of 0.48–1.22 MPa, have been observed via high-speed shadowgraphic imaging at 1 × 106 frames per second. Clouds underwent repetitive growth, oscillation and collapse (GOC) cycles, with shock-waves emitted periodically at the instant of collapse during each cycle. The frequency of cloud collapse, and coincident shock-emission, was primarily dependent on the intensity of the focused ultrasound driving the activity. The lowest peak-to-peak pressure amplitude of 0.48 MPa generated shock-waves with an average period of 7.9 ± 0.5 μs, corresponding to a frequency of f0/2, half-harmonic to the fundamental driving. Increasing the intensity gave rise to GOC cycles and shock-emission periods of 11.8 ± 0.3, 15.8 ± 0.3, 19.8 ± 0.2 μs, at pressure amplitudes of 0.64, 0.92 and 1.22 MPa, corresponding to the higher-order subharmonics of f0/3, f0/4 and f0/5, respectively. Parallel passive acoustic detection, filtered for the fundamental driving, revealed features that correlated temporally to the shock-emissions observed via high-speed imaging, p(two-tailed) < 0.01 (r = 0.996, taken over all data). Subtracting the isolated acoustic shock profiles from the raw signal collected from the detector, demonstrated the removal of subharmonic spectral peaks, in the frequency domain. The larger cavitation clouds (>200 μm diameter, at maximum inflation), that developed under insonations of peak-to-peak pressure amplitudes >1.0 MPa, emitted shock-waves with two or more fronts suggesting non-uniform collapse of the cloud. The observations indicate that periodic shock-emissions from acoustically driven cavitation clouds provide a source for the cavitation subharmonic signal, and that shock structure may be used to study intra-cloud dynamics at sub-microsecond timescales. 相似文献
114.
Gerold Schick Armin Loew Martin Nieger Edgar Niecke 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The synthesis, crystal structure, polymerisation and metal complexation of aminobis(diorganylamino)phosphanes are discussed. 相似文献
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118.
Gerold Wagner 《Journal d'Analyse Mathématique》1988,50(1):159-167
119.
The kinetics of the transformation from the disordered f.c.c. to the ordered b.c.t. were studied in Au4V by measuring electrical resistivity, magnetic susceptibility and microhardness. The resistivity maximum is related to the SRO, whereas the correlation of the above mentioned properties with the integrated X-ray intensity of the superlattice lines shows that the magnetic changes occur simultaneously with the nucleation and growth of the ordered phase. 相似文献
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