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51.
Wolf-Dieter Garber 《Communications in Mathematical Physics》1975,42(3):195-208
It is shown that the time-slice axiom and the diamond property are equivalent for the generalized free field. If, in addition, there is a mass gap, duality is equivalent to either causality requirement. It is further shown that the local rings associated with certain space-time regions are factors in the case of causal generalized free fields with mass gap. Necessary and sufficient conditions for causality and duality and some examples for causal and acausal generalized free fields are also given. 相似文献
52.
Carsten Knapp Tobias Borrmann Enno Lork Paul G. Watson Wolf-Dieter Stohrer Rüdiger Mews 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4-5):887-890
The bicyclic sulfur-nitrogen heterocycle F3CCN5S3 (1) was investigated as a donor and acceptor toward H+, metal cations, and F?. Whereas the protonated species F3CCN5S3H+ AsF6 ? (2) can be isolated, the product of the reaction with F? is unstable and decomposes among other products to TAS+ F3CCN5S3NC(NH2)CF3 ? (3), which is isolated from this reaction in small amounts. 相似文献
53.
Laback B Zimmermann I Majdak P Baumgartner WD Pok SM 《The Journal of the Acoustical Society of America》2011,130(3):1515-1529
The envelope shape is important for the perception of interaural time difference (ITD) in the envelope as supported by the improved sensitivity for transposed tones compared to sinusoidally amplitude-modulated (SAM) tones. The present study investigated the effects of specific envelope parameters in nine normal-hearing (NH) and seven cochlear-implant (CI) listeners, using high-rate carriers with 27-Hz trapezoidal modulation. In NH listeners, increasing the off time (the silent interval in each modulation cycle) up to 12 ms, increasing the envelope slope from 6 to 8 dB/ms, and increasing the peak level improved ITD sensitivity. The combined effect of the off time and slope accounts for the gain in sensitivity for transposed tones relative to SAM tones. In CI listeners, increasing the off time up to 20 ms improved sensitivity, but increasing the slope showed no systematic effect. A 27-pulses/s electric pulse train, representing a special case of modulation with infinitely steep slopes and maximum possible off time, yielded considerably higher sensitivity compared to the best condition with trapezoidal modulation. Overall, the results of this study indicate that envelope-ITD sensitivity could be improved by using CI processing schemes that simultaneously increase the off time and the peak level of the signal envelope. 相似文献
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Rüdiger Mews Tobias Borrmann Enno Lork Jan Petersen Wolf-Dieter Stohrer Paul G. Watson 《Journal of fluorine chemistry》2004,125(11):1649-1655
One of the most interesting compounds in sulfur nitrogen fluorine chemistry is NSF2NS(O)F2 (3) (reported by Glemser and Höfer 30 years ago): in the NS backbone a triple and a double bond are connected by a single bond. Electrophiles (metal cations, fluoro Lewis acids, “CH3+”) attack this multifunctional system exclusively at the thiazyl nitrogen of the triple bond. [M(NSF2NS(O)F2)4][AsF6]2 (M = Ni (4b), Cu (4c)), [Re(CO)5(NSF2NS(O)F2)][AsF6]− (5), F5A·NSF2NS(O)F2 (A = As (6), Sb (7)), F3B·NSF2NS(O)F2 (8) and [H3CNSF2NS(O)F2]+[AsF6]− (9) were isolated. The X-ray structures of 4c, 6, 8 and 9 are reported, bonding in these complexes is compared with the recently reported related NSAr2NS(X)Ar2 (X = O, NH) species. 相似文献