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101.
102.
K. Morigaki Y. Sano I. Hirabayashi M. Konagai M. Suzuki 《Solid State Communications》1982,43(10):751-755
The position of the energy level of dangling bond centres and its broadening have been investigated by optically detected magnetic resonance measurements in aSi, aSi:H and aSi:H, F. Correlation between level broadening and increase in the bandgap energy is discussed. 相似文献
103.
A. Maki S. Mikamo M. Ono M. Takasaki A. Yamamoto H. Hirabayashi S. Kurokawa A. Kusumegi S. Higashi F. Kajino Y. Kawashima M. Nakashita S. Ozaki T. Takahashi Y. Teramoto S. Yamamoto S. Naito Y. Sakai M. Mishina 《Physics letters. [Part B]》1981,106(5):423-427
Direct production of single electrons in proton-nucleus collisions at 13 GeV/c has been measured. A rising ratio with decreasing pT above the 10?4 level is observed for low pT single electrons. The source of the rising ratio at low ratio at low pT is discussed in connection with the low mass dielectron continuum below the ? mass region. 相似文献
104.
Toshihiko Nagamura Kazunori Fukitani Motowo Takayanagi 《Journal of Polymer Science.Polymer Physics》1975,13(8):1515-1532
The micromechanism of tensile deformation of poly[p-(2-hydroxyethoxy)benzoic acid] fibers is discussed on the basis of a detailed esr study of radical formation. The concentration of primary phenoxy radicals, which were detected during deformation at room temperature as a direct indicator of main-chain rupture, was determined by extrapolating the radical decay curves at various strains to zero time. The relation between the initial radical concentration and the strain is well expressed by the cumulative normal distribution curve. By use of this relation and a model of fiber structure, the distribution of the contour length of tie chains was determined. No radicals were detected during a second stretching cycle until the maximum strain in the first run was exceeded. The deformation model which includes alternating crystalline and amorphous regions connected by tie chains, a distribution of contour lengths of tie chains, and a phase transformation of molecular chains in the crystalline region accounted fairly well for the observed stress–strain behavior of monofilaments in first and second stretching cycles. The comparison between the observed and the calculated radical concentration suggests that statistical factors and other deformation mechanisms have to be taken into account. 相似文献
105.
Fatigue of the luminescence in amorphous SiH alloys has been investigated as a function of dangling bond density and of hydrogen content at 2 K. Optically detected magnetic resonance measurements have also been carried out to elucidate the origin of the fatigue effect for those samples. 相似文献
106.
107.
Kiyoshi Tanaka Tomoya Okada Fumio Yoneda Tomohisa Nagamatsu Kazunori Kuroda 《Tetrahedron letters》1984,25(16):1741-1742
1,5-Dihydro-5-deazaflavin derivatives possessing a chiral substituent at N(3) position were synthesized, with which moderate asymmetric induction was observed in the reduction of ethyl benzoylformate. 相似文献
108.
Radiative and nonradiative recombination processes have been investigated by measurements of optically detected magnetic resonance at 2 K in hydrogenated anorphous silicon. Relevant processes are discussed on the basis of the experimental results. 相似文献
109.
Maeda Y Miyashita J Hasegawa T Wakahara T Tsuchiya T Feng L Lian Y Akasaka T Kobayashi K Nagase S Kako M Yamamoto K Kadish KM 《Journal of the American Chemical Society》2005,127(7):2143-2146
The chemical reduction and oxidation of M@C82 (M = Y, La, and Ce) afford the corresponding anion and cation, respectively, which show unique and interesting chemical reactivities. It is found that the successful reversible gain or loss of electrons by ionization is useful for controlling the stability and reactivity of M@C82 toward both nucleophiles and electrophiles. 相似文献
110.
Ochiai M Takeuchi Y Katayama T Sueda T Miyamoto K 《Journal of the American Chemical Society》2005,127(35):12244-12245
Reported here for the first time is the iodobenzene-catalyzed alpha-oxidation of ketones, in which diacyloxy(phenyl)-lambda3-iodanes generated in situ act as real oxidants of ketones and m-chloroperbenzoic acid serves as a terminal oxidant. Oxidation of a ketone with m-chloroperbenzoic acid in acetic acid in the presence of a catalytic amount of iodobenzene, BF3.Et2O, and water at room temperature under argon affords an alpha-acetoxy ketone in good yield. p-Methyl- and p-chloroiodobenzene also serve as efficient catalysts in this direct oxidation. We found that when the reaction was carried out in the absence of a catalytic amount of iodobenzene, Baeyer-Villiger oxidation of a ketone took place. It is noted that use of water and BF3.Et2O is crucial to the success of this alpha-acetoxylation. 相似文献