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181.
182.
Isoindole or 1H-isoindole, where there is the possibility of tautoinerism, is too unstable to be isolated, and its existence is ascertained only by Diels-Alder addition products with maleic anhydride and N-phenylmaleinimide.1) Moreover, the systematic preparations of isoindole derivatives have not been confirmed.2) However, several successful isoindole syntheses have been realized from ortho-disubstituted benzene derivatives. For instance,3) catalytic reduction over Raney nickel of o-cyanobenzophenone gave 1-phenylisoindole, accompanied by the oxidative coupling product. We wish to report now a synthesis of an isoindole derivative (2) by the dimerization of o-tolunitrile and several reactions of the compound (2), and the physical data were also reported. 相似文献
183.
The purposes of this paper are to clarify the relation between listener envelopment (LEV) and two physical factors, namely, early-to-late sound level C80 and directional late energy ratios (DLRs), and to demonstrate the significance of evaluating LEV using C80 and DLRs. Firstly, two psychological experiments are performed. In the first experiment, the results show that the previous findings about the effects of late reflections from lateral, overhead, and behind the listener on LEV are valid when they also consist of plural directional energy components, as are found in real sound fields. In the second experiment, the relational equation among LEV, C80, and DLRs is derived from results when the physical factors are simultaneously varied. Secondly, psychological scores for LEV are calculated in actual halls by applying measured values for C80 and DLRs to the equation. The results show that the differences in LEV among different seating positions and in the spatial uniformity of LEV among different halls are expected to be significantly large depending on the values of C80 and DLRs. This suggests the significance of evaluating LEV by means of C80 and DLRs. 相似文献
184.