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61.
Etou J Ino D Furukawa D Watanabe K Nakai IF Matsumoto Y 《Physical chemistry chemical physics : PCCP》2011,13(13):5817-5823
We have investigated the mechanism of enhanced absorption intensities of vibrational bands of adsorbates on copper meshes with subwavelength holes by measuring and simulating temporal profiles of infrared pulses transmitted through the meshes. As reported previously [Williams et al., J. Phys. Chem. B, 2003, 107, 11871], the absorption intensities of CH stretching bands of alkanethiolate adsorbed on the mesh increase substantially with decreasing hole size. The enhancements of absorption intensities are associated with temporal delays of infrared pulses transmitted through the mesh. Finite difference time domain calculations reproduce the observed pulse delays as a function of hole size. These facts indicate that the delays of transmitted pulses are not caused by coupling of infrared radiation to surface plasmon polaritons propagating on the front and rear surfaces of the mesh, but they are caused by the reduction in group velocity owing to coupling to waveguide modes of mesh holes. Consequently, the strong enhancements of the absorption intensities are attributed to adsorbates inside the holes rather than to those on the mesh surfaces that have been proposed previously. 相似文献
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To clarify the role of formant frequency in the perception of pitch in whispering, we conducted a preliminary experiment to determine (1.) whether speakers change their pitch during whispering; (2.) whether listeners can perceive differences in pitch; and (3.) what the acoustical features are when speakers change their pitch. The listening test of whispered Japanese speech demonstrates that one can determine the perceived pitch of vowel /a/ as ordinary, high, or low. Acoustical analysis revealed that the perception of pitch corresponds to some formant frequencies. Further data with synthesized whispered voice are necessary to confirm the importance of the formant frequencies in detail for perceived pitch of whispered vowels. 相似文献
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67.
O. Hashimoto A. Sumi T. Nomura S. Nagamiya K. Nakai T. Yamazaki K. Miyano 《Nuclear Physics A》1974,218(1):180-188
The spin rotation of the 0.57 ms 7+state in202Tl has been observed by use of a pulsed magnetic field and the g-factor was determined to be 0.128 ± 0.006. The isomeric state was excited via the 204Hg(p, 3n)202Tl reaction with a 28 MeV pulsed beam of 1.2 ms interval. From the results, the main configuration of the 7+ state in202Tl is interpreted as (). 相似文献
68.
Summary Measurements of photoluminescence and luminescence excitation spectra of ZnSiP2 have been performed at 4.2K and two results were obtained. One is the observation of a new sharp emission line at 1.980 eV,
due to the bound exciton associated with the pseudodirect gap. The other is the observation of another new series of absorption
lines in the luminescence excitation spectrum of an emission line, at 1.984 eV, in addition to those reported previously.
These results indicate that in ZnSiP2 radiative transitions occur at both the indirect and the pseudodirect gaps.
Paper presented at the ?V International Conference on Ternary and Multinary Compound?, held in Cagliari, September 14–16,
1982. 相似文献
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