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71.
Fujimori A Taguchi M Hakozaki S Kamishima K Ochiai B 《Langmuir : the ACS journal of surfaces and colloids》2012,28(29):10830-10837
Surface complexing (i.e., metal-bridged polymerization in this study) of a three-armed amphiphilic compound with metal-scavenging properties has been investigated using the surface pressure-area (π-A) isotherms of a Langmuir monolayer from the subphase. Inductively coupled plasma mass spectrometry (ICP-MS) was also carried out on eluted solutions from corresponding multilayers of the solid. Furthermore, the molecular arrangement and surface morphology of organized molecular films of the resultant comb polymer were estimated by in-plane and out-of-plane X-ray diffraction (XRD) and by atomic force microscopy. From an analysis of the wide-angle X-ray diffraction of the corresponding monomer in the bulk, the long hydrocarbon chains are observed to pack hexagonally in the solid state. Compared to their monolayer on distilled water as the subphase, a polymerized monolayer on a buffer solution containing Cd(2+) ions is remarkably expanded at 15 °C. From ICP-MS and IR measurements, it is found that this monolayer stoichiometrically contains Cd(2+) ions on the -SH group. It is found by XRD that highly ordered layer structures and regular 2D lattices are constructed in the organized molecular films of the Cd-bridged comb polymer. Furthermore, the surface morphology of Langmuir-Blodgett films fabricated from the monolayers on a buffer solution containing Cd(2+) and Pd(2+) shows flat and smooth domains upon metal scavenging and polymerization. 相似文献
72.
73.
We theoretically study a possible topological superconductivity in the interacting two layers of Rashba systems, which can be fabricated by the heterostructures of semiconductors and oxides. The hybridization, which induces the gap in the single particle dispersion, and the electron-electron interaction between the two layers leads to the novel phase diagram of the superconductivity. It is found that the topological superconductivity without breaking time-reversal symmetry is realized when (i) the Fermi energy is within the hybridization gap, and (ii) the interlayer interaction is repulsive, both of which can be satisfied in realistic systems. Edge channels are studied in a tight-binding model numerically, and the several predictions on experiments are also given. 相似文献
74.
Norimitsu Yoshida Sho Terazawa Kotaro Hayashi Tomonari Hamaguchi Hironori Natsuhara Shuichi Nonomura 《Journal of Non》2012,358(17):1987-1989
Effects of deposition conditions on the structure of microcrystalline silicon carbide (μc-SiC) films prepared by hot-wire chemical vapor deposition (hot-wire CVD) method have been investigated. It is found from X-ray diffraction patterns of the film that a diffraction peak from crystallites from hexagonal polytypes of SiC is observed in addition to those of 3 C-SiC crystallites. This result is obtained in the film under a narrow deposition conditions of SiH3CH3 gas pressure of 8 Pa, the H2 gas pressure of 80–300 Pa and the total gas pressure of 40–300 Pa under fixed substrate and filament temperatures employed in this study. Furthermore, the grain size of hexagonal crystallites (about 20 nm) on c-Si substrates becomes larger than that of 3 C-SiC crystallites (about 10 nm) for the films deposited under the total gas pressure of 36–88 Pa. The fact that microcrystalline hexagonal SiC can be deposited under limited deposition conditions could be interpreted in the context of a result for c-SiC polytypes prepared by thermal CVD method. 相似文献
75.
76.
Eiichi Masumoto Hiroshi Maruoka Fumi Okabe Sho Nishida Ryoko Tomita Toshihiro Fujioka Kenji Yamagata 《Journal of heterocyclic chemistry》2012,49(4):893-899
A novel synthetic route to 4‐pyridazineacetic acids 10 – 12 has been achieved by the ring‐expansion reaction of N‐cyanomethylated 3‐pyrazoline‐4‐acetic acids 7 – 9 . 1H‐Pyrazole‐4‐acetic acids 1 – 3 were reacted with iodoacetonitrile in the presence of triethylamine in refluxing acetonitrile to give the corresponding C‐cyanomethylated 1H‐pyrazole‐4‐acetic acids 4 – 6 as major products together with N‐cyanomethylated 3‐pyrazoline‐4‐acetic acids 7 and 8 as minor products. On the other hand, reactions of 1 and 3 with chloroacetonitrile in the presence of triethylamine in refluxing chloroform afforded the corresponding N‐cyanomethylated 3‐pyrazoline‐4‐acetic acids 7 and 9 as major products. Thermal treatment of 7 – 9 with sodium hydride in N,N‐dimethylformamide caused ring expansion to yield the corresponding 4‐pyridazineacetic acids 10 – 12 . 相似文献
77.
The cross sections of
Ω+Ω→(ΩΩ)Jπ=0++X
are studied by using an effective Hamiltonian method. The results
are σΩ+Ω→(ΩΩ)0++γ=0.03~0.16×10-29 cm2 for
pΩ=100~400 MeV, and
the cross sections of η production are about 10-28 cm2 for
pΩ > 880 MeV. 相似文献
78.
SHA Chin-Kang CHIU Rei-Torng LIH Shinn-Horng SANTHOSH K.C CHANG Ching-Jung TSENG Wei-Hong HO Wen-Yueh 《高等学校化学研究》2001,17(3)
Intramolecular radical cyclization reactions are now used routinely to synthesize carbocyclic and heterocyclic structures. We have reported that α-carbonyl radicals 1, generated from the corresponding iodo ketones or enones, underwent intramolecular radical cyclization smoothly to afford products 2.1, 2,3 相似文献
79.
讨论了静态时序分析算法及其在IC设计中的应用。首先,文章讨论了静态时序分析中的伪路径问题以及路径敏化算法,分析了影响逻辑门和互连线延时的因素。最后通过一个完整的IC设计流程介绍了静态时序分析的应用。 相似文献
80.
Kwok-Pun HO 《数学物理学报(B辑英文版)》2021,(4):1263-1274
Boyd's interpolation theorem for quasilinear operators is generalized in this pa-per,which gives a generalization for both the Marcinkiewicz interpolation theor... 相似文献