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571.
N. Rubido C. Cabeza S. Kahan G.M. Ramírez Ávila Arturo C. Marti 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,62(1):51-56
Stable synchronous states of different order were analytically, numerically and
experimentally characterized in pulse-coupled light-controlled oscillators (LCOs). The
Master-Slave (MS) configuration was studied in conditions where different time-scale
parameters were tuned under varying coupling strength. Arnold tongues calculated
analytically – based on the piecewise two-time-scale model for LCOs – and obtained
numerically were consistent with experimental results. The analysis of the stability
pattern and tongue shape for (1 : n) synchronization was based on the
construction of return maps representing the Slave LCO evolution induced by the action of
the Master LCO. The analysis of these maps showed that both tongue shape and stability
pattern remained invariant. Considering the wide variation range of LCO parameters, the
obtained results could have further applications on ethological models. 相似文献
572.
Experimental measurements of the latency of transient evoked otoacoustic emission and auditory brainstem responses are compared, to discriminate between different cochlear models for the backward acoustic propagation of otoacoustic emissions. In most transmission-line cochlear models otoacoustic emissions propagate towards the base as a slow transverse traveling wave, whereas other models assume fast backward propagation via longitudinal compression waves in the fluid. Recently, sensitive measurements of the basilar membrane motion have cast serious doubts on the existence of slow backward traveling waves associated with distortion product otoacoustic emissions [He et al., Hear. Res. 228, 112-122 (2007)]. On the other hand, recent analyses of "Allen-Fahey" experiments suggest instead that the slow mechanism transports most of the otoacoustic energy [Shera et al., J. Acoust. Soc. Am. 122, 1564-1575 (2007)]. The two models can also be discriminated by comparing accurate estimates of the otoacoustic emission latency and of the auditory brainstem response latency. In this study, this comparison is done using human data, partly original, and partly from the literature. The results are inconsistent with fast otoacoustic propagation, and suggest that slow traveling waves on the basilar membrane are indeed the main mechanism for the backward propagation of the otoacoustic energy. 相似文献
573.
An experimental demonstration of the mechanical transfer of orbital angular momentum to matter from acoustical vortices in free field is presented. Vortices with topological charges l=+/-1 and l=+/-2 were generated and a torsion pendulum was used to study the angular momentum transfer to hanging disks of several sizes. This allowed us to make a comparative study of the effective acoustical torque in terms of topological charge of the vortex, the disk radius, and its position along the main propagation axis. A theoretical discussion of the generated sound fields is also provided. 相似文献
574.
Franco M. Rabagliati Mnica A. Prez Rodrigo A. Cancino Marcelo A. Soto Francisco J. Rodríguez Carlos J. Caro Arturo G. Len Hugo A. Ayal Raúl Quijada 《Macromolecular Symposia》2001,168(1):31-42
Combined systems including diphenylzinc, Ph2Zn, a metallocene, and methylaluminoxane, MAO, have been employed to initiate styrene polymerization. These initiator systems have been also used to initiate the copolymerization of styrene with p‐alkylsubstituted styrenes and with α‐olefins. Both polymerization and copolymerization processes depend on the nature of the metallocene included in the initiator system, the presence of Ph2Zn, the temperature and the solvent used. Titanocenes produced syndiotactic polystyrene, s‐PS, while zirconocenes gave atactic polystyrene, a‐PS, with a certain content, less the 20% of s‐PS. For copolymerizations the conversion to polymer was also influenced by the comonomer nature and its molar proportion in the initial feed, as well as the sort of metallocene, titanocene or zirconocene included. 相似文献
575.