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We analyze the effects of inelastic scattering on the tunneling time theoretically, using generalized Nelson’s quantum mechanics.
This generalization enables us to describe quantum system with channel couplings and optical potential in a real time stochastic
approach, which seems to give us a new insight into quantum mechanics beyond Copenhagen interpretation 相似文献
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For the construction of new combinatorial libraries, a lead compound was created by replacing the core structure of a hit compound discovered by screening for cytotoxic agents against a tumorigenic cell line. The newly designed compound maintained biological activity and allowed alternative library construction for antitumor drugs. 相似文献
128.
A new ring transformation of 3-halo-2-azidopyridine 1-oxides. A novel synthesis of 1,2-oxazin-6-ones
Rudolph A. Abramovitch Ichiro Shinkai Berkeley W. Cue Francis A. Ragan Jerry L. Atwood 《Journal of heterocyclic chemistry》1976,13(2):415-417
The course of the thermal ring-opening and recyclization of 2-azidopyridine 1-oxides is radically altered by the presence of a 3-halo substituent. Provided the 6-position is blocked, recyclization leads to a 6-cyano-6-halo-1,2-oxazine which hydrolyzes very readily to the 6H-1,2-oxazin-6-one. The structure of 4-bromo-3-methyl-6H-1,2-oxazin-6-one so obtained was confirmed by single crystal X-ray analysis. If the 6-position is not blocked, the product undergoes a further ring opening to give (Z)-β-cyanoacrylates. 相似文献
129.
Takemoto H Honda K Masaki S Shimada Y Fujimoto I 《The Journal of the Acoustical Society of America》2006,119(2):1037-1049
A 3D cine-MRI technique was developed based on a synchronized sampling method [Masaki et al., J. Acoust. Soc. Jpn. E 20, 375-379 (1999)] to measure the temporal changes in the vocal tract area function during a short utterance /aiueo/ in Japanese. A time series of head-neck volumes was obtained after 640 repetitions of the utterance produced by a male speaker, from which area functions were extracted frame-by-frame. A region-based analysis showed that the volumes of the front and back cavities tend to change reciprocally and that the areas near the larynx and posterior edge of the hard palate were almost constant throughout the utterance. The lower four formants were calculated from all the area functions and compared with those of natural speech sounds. The mean absolute percent error between calculated and measured formants among all the frames was 4.5%. The comparison of vocal tract shapes for the five vowels with those from the static MRI method suggested a problem of MRI observation of the vocal tract: data from static MRI tend to result in a deviation from natural vocal tract geometry because of the gravity effect. 相似文献
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