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54.
Hirofumi Matsuhata Hirotaka Yamaguchi Tamotsu Yamashita Toshiaki Tanaka Bin Chen Takashi Sekiguchi 《哲学杂志》2013,93(15):1674-1685
Shockley partial dislocations in 4H-SiC were observed using monochromatic synchrotron X-ray topography with a grazing-incidence Bragg-case geometry, that is, Berg–Barrett topography. The contrast of partial dislocations at the edges of Shockley-type stacking faults is discussed in terms of whether they have C- or Si-core edge components, or screw components. The dissociated state of basal-plane dislocation is discussed on a basis of the stacking sequence for basal-planes in the 4H-SiC crystal structure. It is expected that the results obtained in this study will be useful for characterizing Shockley-type stacking faults in Berg–Barrett topography. 相似文献
55.
A. K. Kurilkin T. Saito V. P. Ladygin T. Uesaka T. A. Vasiliev M. Janek M. Hatano A. Yu. Isupov H. Kato N. B. Ladygina Y. Maeda A. I. Malakhov J. Nishikawa T. Ohnishi H. Okamura S. G. Reznikov H. Sakai N. Sakamoto S. Sakoda Y. Satou K. Sekiguchi K. Suda A. Tamii N. Uchigashima K. Yako 《The European physical journal. Special topics》2008,162(1):133-136
The data on the vector A
y
and tensor A
yy
, A
xx
, A
xz
analyzing powers for the
d → 3H p reaction have been obtained at the energy of the initial deuteron of 200MeV in the angular range of 0–95 degrees in the c.m.s.
The calculations performed within one-nucleon exchange model with the use of the standard three-nucleon bound state wave functions
fail to reproduce the data on the tensor analyzing powers. 相似文献
56.
H. Mardanpour H. R. Amir-Ahmadi R. Benard A. Biegun M. Eslami-Kalantari N. Kalantar-Nayestanaki M. Kiš St. Kistryn A. Kozela H. Kuboki Y. Maeda M. Mahjour-Shafiei J. G. Messchendorp K. Miki S. Noji A. Ramazani-Moghaddam-Arani H. Sakai M. Sasano K. Sekiguchi E. Stephan R. Sworst Y. Takahashi K. Yako 《Few-Body Systems》2008,44(1-4):49-52
A systematic study of three-nucleon force (3NF) effects in break-up reactions has been carried out at KVI at several energies. In this article, the p + d → p + p + n reaction with a polarized-proton beam of 190?MeV will be discussed. The experiment was performed by exploiting a new detector called BINA. Some results for high-precision vector analyzing powers and differential cross sections are presented and compared with state-of-the-art Faddeev calculations with or without 3NF. 相似文献
57.
Toru Oikawa Norio Nakata Takeshi Matsumoto Yoshio Kabe Akira Sekiguchi 《Heteroatom Chemistry》2008,19(1):87-92
The irradiation of silyl-substituted 1,4-disila(Dewar-benzene) 1 with light of wavelength λ > 320 nm in the presence of 2,6-dimethylphenyl-isocyanide or phenylacetylene produced 1,4-bis(di-tert-butylmethylsilyl)-2,3,5,6-tetraethyl-7-(2,6-dime-thylphenylimino)-1,4-disilabicyclo[2.2.1]hepta-2,5-diene 5 or 1,4-bis(di-tert-butylmethylsilyl)-2,3,5,6-tetraethyl-1-(2-phenylethynyl)-1,4-disilacyclohexa-2,5-diene 6 , respectively. The molecular structures of 5 and 6 were determined by spectroscopic data and X-ray crystallography. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:87–92, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20411 相似文献
58.
Chieko Kogawa Asuka Fujiwara Ryuta Sekiguchi Taku Shoji Jun Kawakami Masaaki Okazaki Shunji Ito 《Tetrahedron》2018,74(49):7018-7029
Azulene analog of tryptanthrin, azuleno[1′,2′:4,5]pyrrolo[2,1-b]quinazoline-6,14-dione, was successfully prepared by the condensation reaction of azuleno[2,1-b]pyrrole-2,3-dione with isatoic anhydride in the presence of sodium hydride or diisopropylethylamine (DIPEA). Its 2-halo derivatives were also obtained in high yields by the condensation reaction with 5-haloisatoic anhydrides in the presence of DIPEA. Reactivity toward electrophilic reagents was revealed by halogenation with N-bromosuccinimide (NBS) or N-iodosuccinimide (NIS) to afford 12-halo derivatives in high yields. Among the halo derivatives, 2-iodo and 12-iodo derivatives were reactive enough to afford phenylethynyl derivatives under Pd-catalyzed Sonogashira cross-coupling conditions. Within the phenylethynyl derivatives, only 12-phenylethynyl derivative was transformed into its 1,1,4,4-tetracyanobutadiene (TCBD) derivative by the reaction with TCNE. Amphoteric redox properties of the novel azulene analogs of tryptanthrin were characterized by spectroscopic and voltammetric analyses. 相似文献
59.
Hitoshi Habuka Mayuka Watanabe Yutaka Miura Mikiya Nishida Takashi Sekiguchi 《Journal of Crystal Growth》2007,300(2):374-381
A polycrystalline silicon carbide film is formed on a silicon surface by chemical vapor deposition using monomethylsilane gas along with hydrogen chloride gas in ambient hydrogen at atmospheric pressure. The film deposition is performed near 1000 K, at which temperature the monomethylsilane maintains a chemical bond between the silicon and carbon present in the molecular structure. The excess amount of silicon on the film surface is reduced using the hydrogen chloride gas. Although the film deposition stops within 1 min after beginning the supply of the monomethylsilane gas and hydrogen chloride gas, annealing at 1273 K in ambient hydrogen after the film deposition allows further deposition so that a thick silicon carbide film can be obtained. 相似文献
60.
Andersson PU Ryding MJ Sekiguchi O Uggerud E 《Physical chemistry chemical physics : PCCP》2008,10(40):6127-6134
Hydrogen/deuterium exchange in reactions of H3O(+)(H2O)n and NH4(+)(H2O)n (1 < or = n < or = 30) with D2O has been studied experimentally at center-of-mass collisions energies of < or = 0.2 eV. For a given cluster size, the cross-sections for H3O(+)(H2O)n and NH4(+)(H2O)n are similar, indicating a structural resemblance and energetics of binding. For protonated pure water clusters, H3O(+)(H2O)n, reacting with D2O the main H/D exchange mechanism is found to be proton catalyzed. In addition the H/D scrambling becomes close to statistically randomized for the larger clusters. For NH4(+)(H2O)n clusters reacting with D2O, the main mechanism is a D2O/H2O swap reaction. The lifetimes of H3O(+)(H2O)n clusters have been estimated using RRKM theory and a plateau in lifetime vs. cluster size is found already at n = 10. 相似文献