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261.
262.
Tetsuya Gotoh Masahide Yamamoto Yasunori Nishijima 《Journal of polymer science. Part A, Polymer chemistry》1981,19(5):1047-1060
Radiation-induced polymerization of styrene in methylene chloride solution or bulk system was investigated to explain the initiation mechanism of cationic polymerization. It was found that high energy radiation produces polymers and dimers. The main dimers were identified as trans-1,2-diphenylcyclobutane, 1-phenyl-1,2,3,4-tetrahydronaphthalene, and 1-phenyl-1,2-dihydronaphthalene. The dimerization procedure was cationic in a pattern similar to that obtained in photoexcited EDA systems. It was shown clearly by product analysis that the bonded dimer cation radical intermediate, which was assumed to be an initiating species of the cationic polymerization, was produced in a radiation-induced polymerization system. The observed polymerization was composed of two types; cationic and radical, the latter initiated by radical species. 相似文献
263.
Teruhiro Shirakura Masahide Kuwada 《Annals of the Institute of Statistical Mathematics》1975,27(1):377-386
It is shown that the characteristic roots of the information matrix of a balanced fractional 2
m
factorial designT of resolution 2l+1 are the same as those of its complementary design
. Necessary conditions for the existence of such a designT are also given. 相似文献
264.
New 1-ethyl-3-methylimidazolium (EMI) salts [EMI][C(CN)3] and [EMI][Ag(CN)2] were prepared and characterized. The C(CN)3 salt has a melting point at -11 degrees C and shows a low viscosity (18 cP) and a high ionic conductivity (1.8 x 10(-2) S cm(-1)) at room temperature. This conductivity is less than that of [EMI][N(CN)2] salt (2.7 x 10(-2) S cm(-1)), possibly due to the larger molecular weight of the anion. The first EMI salt containing Ag(I) complexes [EMI][Ag(CN)2] has a higher melting point of 73 degrees C. In the crystal, the C-H...pi interionic interactions between cations construct zigzag chains in the cationic two-dimensional layer. Close Ag..Ag interionic contacts of 3.226(1) A were observed in the one-dimensional anionic chain, and the relatively high melting point among the EMI salts with a monoanion appears to be governed essentially by these direct Ag...Ag interactions. 相似文献
265.
266.
Masahide Ohno 《Journal of Electron Spectroscopy and Related Phenomena》2001,120(1-3):33-45
The inherent post-collision interaction (PCI) between an Auger-electron and a spectator electron in core-hole decay in metals and charge-transfer systems is described in a systematic maimer by a many-body theory. The inherent PCI effect on spectator Auger-transition spectral lineshapes of metals and charge-transfer systems is discussed. The spectator Auger-transition energy shift due to a change of chemical environment is discussed in the light of the inherent PCI. 相似文献
267.
Takashi Goto Akinari Niimi Ken Hirano Nozomu Takahata Shin-ichiro Fujita Masahide Shimokawabe Nobutsune Takezawa 《Reaction Kinetics and Catalysis Letters》2000,69(2):375-378
At lower temperatures or in the presence of O2, metal oxides showed higher turnover frequency for the decomposition of N2O than corresponding metal ion exchanged ZSM-5. 相似文献
268.
Masahide Ohno 《Journal of Electron Spectroscopy and Related Phenomena》2008,162(3):134-145
The relative spectral intensity of the band-like two M4,5-hole state to the atomic-like localized one is much suppressed in the coincidence M3–M4,5M4,5 super Coster–Kronig (sCK) electron spectrum of Cu metal compared to the one in the coincidence L3–M4,5M4,5 Auger electron spectroscopy (AES) spectrum. The M3-hole lifetime width of Cu metal is calculated by an ab initio atomic many-body theory (the extended relaxed core random phase approximation with exchange). The calculated M3-hole lifetime width of Cu metal agrees well with the experimental one. The M3–M4,5M4,5 sCK decay width of Cu metal decreases much with delocalization of the two M4,5 holes in the sCK final state, whereas the Auger decay width is fairly independent of localization and delocalization of the two M4,5 holes in the Auger final state. Thus, the relative spectral intensity of the band-like state is much suppressed in the coincidence M3–M4,5M4,5 sCK-electron spectrum of Cu metal compared to the one in the coincidence L3–M4,5M4,5 AES spectrum. 相似文献
269.
The coincidence N23-VV Auger-electron spectroscopy (AES) spectra and N23 photoelectron spectroscopy (PES) spectra of Ag metal are analyzed. Here NX is the notation for atomic shell Nx (X = 2, 3). The band-like feature in the coincidence N23-VV AES spectra is much more intense than that in the coincidence M45-VV ones because the potential in the delocalized two-hole state is less attractive than that in the localized one. The partial N23-VV super Coster–Kronig (sCK) transition rate depends critically on both the final-state potential and the sCK-electron kinetic energy (KE) because the KE is low, whereas the partial M45-VV Auger-transition rate is fairly independent of them because the KE is very high. As a result, the partial sCK-transition rate to the band-like state is enhanced compared to that to the atomic-like localized state. The low KE tail in the coincidence N23-VV AES spectra which is likely due to the sCK transition involving more than two electrons, is more enhanced than that in the coincidence M45-VV ones. This is due to the enhancement of the partial sCK-transition rate by the presence of extra holes in the final state. The sharp peaks of small intensity on the lower KE side of the main line in the coincidence N2 PES spectrum are tentatively attributed to the shakeup satellites. 相似文献
270.