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71.
72.
73.
The photochemical behavior of N-acyliminoisoquinolinium and -quinolinium betaines has been investigated. In contrast to pyridinium betaines, the principal course of reaction is the 1,2-migration of N-acylamino groups. Substituent effects as well as solvent effects are observed. The results are rationalized in terms of diaziridine intermediates. 相似文献
74.
We have determined the location of the miscibility gap in liquid Bi-BiBr3 system in the concentration-temperature, x?T, plane from the measurement of the electrical conductivity. The measurements have been done in the concentration range between 30.5 and 92.5 mol.% Bi and in the temperature range between 300 and 600°C. It is found that the temperature dependence of the conductivity of the mixture changes near the retrograde solubility region. 相似文献
75.
Yasumitsu Tamura Yasuyoshi Miki Jun-Ichi Minamikawa Masazunu Ikeda 《Journal of heterocyclic chemistry》1974,11(5):675-679
The mono-N-amino salts of 3-phenylcinnoline, phthalazine, 1-phenylphthalazine, 4-phenylquinazoline, 2-phenylquinoxaline, 1,5- and 1,8-naphthyridines are in high yields prepared by direct N-amination of the parent heterocycles with O-mesitylenesulfonylhydroxylamine. With the one expection of 3-phenylcinnoline, the site of N-amination was determined by mass and nmr spectral techniques. The results indicate that the N-amination occurs preferentially at the least sterically hindered nitrogen atom. 相似文献
76.
Under the Pummerer reaction conditions, N-(1-cyclohexenyl)-N-methyl-α-(methylsulfinyl)acetamide () cyclized in a 5-endo trigonal fashion through the intermediary cation () to give the tetrahydro-4H-oxindole (). The reaction was successively applied to a novel synthesis of erythrinane skeleton. 相似文献
77.
78.
The growth, movement and nature of outside dislocation, which propagate from heavily phosphorus (>1015 ions/cm2) implanted (111), (100), and (110) silicon layers into unimplanted outside regions by a compressive strain induced during
1100° C wet O2 annealing, are investigated using transmission electron microscopy and x-ray diffraction topography. Outside dislocations
are formed, mainly on (111) planes., by the glide motion of dislocation networks formed in implanted layers during early annealing.
This results in dislocations extending into the unimplanted areas to different degrees, in the order of, from the largest
to smallest, (111), (110), and (100) wafers. In (110) wafers, the [001] oriented dislocations in the implanted regions rise
to the surface at the implant and unimplant boundary. On the other hand, the [110] dislocations penetrate into the unimplanted
region. Two sets of orthogonal 〈110〉 oriented dislocations generated in (100) implanted wafers behave in the same manner as
the [001] dislocations in (110) wafers. Some sources of the compressive strain related to the generation of these dislocations
are discussed. 相似文献
79.
Tamura R Takeuchi T Aoki C Takeuchi S Kiss T Yokoya T Shin S 《Physical review letters》2004,92(14):146402
Ca 2p-3d resonant photoemission spectroscopy of a Cd6Ca crystalline approximant unambiguously demonstrates that the low-lying unoccupied 3d levels of calcium are lowered below the Fermi energy by the formation of the approximant, as suggested from electronic structure calculations [Phys. Rev. Lett. 87, 206408 (2001)]]. Moreover, the Ca 3d partial density of states (DOS) obtained near the Fermi energy is in reasonable agreement with theoretical Ca 3d DOS. These results verify the unconventional picture that the origin of the pseudogap in the Cd-based quasicrystals is due to hybridization of the Ca 3d band with the Cd 5p band. 相似文献
80.
cis-Decalin (2) and perylene (3) are co-enclathrated by a self-assembled M6L4-coordination cage (1) to give 1 superset(2.3) although each of them is not enclathrated. This phenomenon is termed as AND bimolecular recognition because enclathration occurs only if 2 and 3 coexist. Cage 1 also coenclathrates azulene (8) and 1,4-naphthoquinone (9) to give 1 superset(8.9). In this case, 1 superset(8)2 and 1 superset(9)2 are formed by treating 1 with 8 and 9 individually. This case is termed as OR bimolecular recognition because enclathration occurs if 8 or 9 exists. Accordingly, we have shown that the self-assembled cage 1 experiences both AND and OR bimolecular recognition. 相似文献