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131.
Haruhiko Ito Katsuaki Koshimura Saori Onitsuka Kohtaro Okada Tsuneo Suzuki Hiroki Akasaka Hidetoshi Saitoh 《Plasma Chemistry and Plasma Processing》2012,32(2):231-248
The dissociative excitation reaction of C2H2 with the electron-cyclotron resonance plasma of Ar was investigated based on the electrostatic-probe measurements and on
the optical emission spectroscopy of the CH(A2Δ–X2Π) transition. The density, n
e, and the temperature, T
e, of free electrons were controlled by adding H2O molecules externally into the reaction region, and the dependence of the CH(A2Δ–X2Π) emission intensity on the addition of H2O was observed to compare with the evaluated dependencies based on n
e and T
e. The mechanism of production of CH(A2Δ) was found, predominantly, to be the electron impact with the contribution of 10–20% of the electron-impact dissociation
of C2H radicals; the contribution of the ion–electron recombination was negligible. Hydrogenated amorphous carbon films were fabricated
using the same reaction system. The atomic compositions, Raman spectra, and the hardness of films were discussed in terms
of the variations of n
e and T
e upon the addition of H2O molecules. 相似文献
132.
For arbitrary non-identically zero functions f, we will introduce some natural fractional functions f 1 having f as denominators and we shall consider their representations f 1 by appropriate numerator functions within a reproducing kernel Hilbert spaces framework. That is, in the present work we would like to introduce very general fractional functions (e.g., having the possibility of admitting zeros in their denominators) by means of the theory of reproducing kernels. 相似文献
133.
Cyano-bridged Mn(III)-M(III) single-chain magnets with M(III)=Co(III), Fe(III), Mn(III), and Cr(III)
Miyasaka H Madanbashi T Saitoh A Motokawa N Ishikawa R Yamashita M Bahr S Wernsdorfer W Clérac R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(13):3942-3954
A series of isostructural cyano-bridged Mn(III)(h.s.)-M(III)(l.s.) alternating chains, [Mn(III)(5-TMAMsalen)M(III)(CN)(6)]?4H(2)O (5-TMAMsalen(2-)=N,N'-ethylenebis(5-trimethylammoniomethylsalicylideneiminate), Mn(III)(h.s.)=high-spin Mn(III), M(III)(l.s.)=low-spin Co(III), Mn-Co; Fe(III), Mn-Fe; Mn(III), Mn-Mn; Cr(III), Mn-Cr) was synthesized by assembling [Mn(III)(5-TMAMsalen)](3+) and [M(III)(CN)(6)](3-). The chains present in the four compounds, which crystallize in the monoclinic space group C2/c, are composed of an [-Mn(III)-NC-M(III)-CN-] repeating motif, for which the -NC-M(III)-CN- motif is provided by the [M(III)(CN)(6)](3-) moiety adopting a trans bridging mode between [Mn(III)(5-TMAMsalen)](3+) cations. The Mn(III) and M(III) ions occupy special crystallographic positions: a C(2) axis and an inversion center, respectively, forming a highly symmetrical chain with only one kind of cyano bridge. The Jahn-Teller axis of the Mn(III)(h.s.) ion is perpendicular to the N(2)O(2) plane formed by the 5-TMAMsalen tetradentate ligand. These Jahn-Teller axes are all perfectly aligned along the unique chain direction without a bending angle, although the chains are corrugated with an Mn-N(axis) -C angle of about 144°. In the crystal structures, the chains are well separated with the nearest inter-chain M???M distance being relatively large at 9?? due to steric hindrance of the bulky trimethylammoniomethyl groups of the 5-TMAMsalen ligand. The magnetic properties of these compounds have been thoroughly studied. Mn-Fe and Mn-Mn display intra-chain ferromagnetic interactions, whereas Mn-Cr is characterized by an antiferromagnetic exchange that induces a ferrimagnetic spin arrangement along the chain. Detailed analyses of both static and dynamic magnetic properties have demonstrated without ambiguity the single-chain magnet (SCM) behavior of these three systems, whereas Mn-Co is merely paramagnetic with S(Mn)=2 and D/k(B)=-5.3?K (D being a zero-field splitting parameter). At low temperatures, the Mn-M compounds with M=Fe, Mn, and Cr display remarkably large M versus H hysteresis loops for applied magnetic fields along the easy magnetic direction that corresponds to the chain direction. The temperature dependence of the associated relaxation time for this series of compounds systematically exhibits a crossover between two Arrhenius laws corresponding to infinite-chain and finite-chain regimes for the SCM behavior. These isostructural hetero-spin SCMs offer a unique series of alternating [-Mn-NC-M-CN-] chains, enabling physicists to test theoretical SCM models between the Ising and Heisenberg limits. 相似文献
134.
Akira Wada Katsuaki Koshimura Masahito Niibe Hidetoshi Saitoh Kazuhiro Kanda Haruhiko Ito 《Journal of Non》2012,358(1):124-128
Amorphous carbon nitride (a-CNx) films were formed from the decomposition of BrCN in the electron cyclotron resonance plasmas of He, Ne, and Ar. The local structures of these films were investigated by the carbon-K near edge X-ray absorption fine structure. It was found that the density of C=C bond in the film prepared with Ar plasma was 7–9 times larger than that with He or Ne plasmas. The [N]/([C] + [N]) ratios of films were estimated from the X-ray photoelectron spectra as 0.34 ± 0.05, 0.35 ± 0.04, and 0.28 ± 0.05 for the He, Ne, and Ar plasmas, respectively. It was found that C atoms in the sp2-hybridized state were incorporated into the two-dimensional and/or one-dimensional conjugated structures composed of ? C=N? in the cases of the He and Ne plasmas and of ? C=C? in the case of the Ar plasma. The compositions and the local structures of films can be explained in terms of a model based on the cyclazine-like network structures. 相似文献
135.
K. Uchida T. Ota K. Harii S. Takahashi S. Maekawa Y. Fujikawa E. Saitoh 《Solid State Communications》2010,150(11-12):524-528
The spin-Seebeck effect (SSE) converts a heat current into a spin current, a flow of spin angular momentum, and spin voltage, the driving force for nonequilibrium spin currents, in a ferromagnetic metal. In this study, the SSE in a ferromagnetic Ni81Fe19 film has been investigated by means of the inverse spin-Hall effect (ISHE) in a Pt film at room temperature. The experimental results measured in the Ni81Fe19/Pt system show that the sign of the thermally induced spin voltage is reversed between the higher- and lower-temperature ends of the Ni81Fe19 film. The ISHE in the Pt film allows us to detect the SSE signal with high sensitivity and to separate it from extrinsic thermoelectric effects. 相似文献
136.
Kumagai K Saitoh M Oyaizu T Furukawa Y Takashima S Nohara M Takagi H Matsuda Y 《Physical review letters》2006,97(22):227002
A Fulde-Ferrell-Larkin-Ovchinnkov (FFLO) state was previously reported in the quasi-2D heavy fermion CeCoIn5 when a magnetic field was applied parallel to the ab plane. Here, we conduct 115In NMR studies of this material in a perpendicular field, and provide strong evidence for FFLO in this case as well. Although the topology of the phase transition lines in the H-T phase diagram is identical for both configurations, there are several remarkable differences between them. Compared to H parallelab, the FFLO phase for H perpendicularab is confined in a much narrower region at the low-T-high-H corner in the H-T plane, and the critical field separating the FFLO and non-FFLO superconducting states almost ceases to have a temperature dependence. Moreover, directing H perpendicularab results in a notable change in the quasiparticle excitation spectrum within the planar node associated with the FFLO transition. 相似文献
137.
Seiji Yamaguchi Miyuki Saitoh Yoshiyuki Kawase 《Journal of heterocyclic chemistry》1991,28(1):125-127
Some ω-3-coumarinyl)alkanoic acids 1a , n = 3-6 were synthesized by cyclization of corresponding ethyl o-formylphenyl alkanedioate 3 with DBU followed by hydrolysis. By a similar cyclization, some ω-(2-chromonyl)alkanoic acids 2a , n = 3-6 were also obtained from the cyclization of corresponding o-acetylphenyl ethyl alkanedioate 4 . 相似文献
138.
Masahiro Ueda Yoshikazu Saitoh Hideki Hachisuka 《Optics and Lasers in Engineering》1990,12(4):245-249
The nature of CO2 laser marking was studied with a view to putting these lasers to practical use in the semiconductor industry. The marking is found to be due to surface spattering rather than burning, which is the main factor in YAG laser marking. The visibility greatly increases by the application of a surface treatment such as marker ink, varnish or poster color. The CO2 laser may therefore be used in place of the YAG laser, now widely used for marking, with some merits: CO2 laser marking is cheaper and faster, and in addition there is no danger of injury from irradiating laser light. 相似文献
139.
Takeshi Nakatani Tomohiro Matsushita Yutaka Miyatake Tomohito Nohno Atsushi Kobayashi Keiki Fukumoto Shunsuke Okamoto Azusa Nakamoto Fumihiko Matsui Ken Hattori Masato Kotsugi Yuji Saitoh Shigemasa Suga Hiroshi Daimon 《Progress in Surface Science》2003,71(5-8):217-239
A stereograph of atomic arrangement was displayed directly on the screen of display-type spherical-mirror analyzer without any computer-aided conversion process for the first time. This stereoscopic photograph enables viewing three-dimensional atomic arrangement. This technique was realized taking advantage of the phenomenon of circular dichroism in photoelectron angular distribution. The azimuthal shifts of forward focusing peaks in a photoelectron angular distribution taken with left and right helicity light in a special arrangement are the same as the parallaxes in a stereo view of atoms. Hence a stereoscopic recognition of three-dimensional atomic arrangement is possible, when the left eye and the right eye respectively view the two images obtained by left and right helicity light simultaneously. 相似文献
140.
Hiroto Watanabe Tohru Saitoh Tamio Kamidate Kensaku Haraguchi 《Mikrochimica acta》1992,106(1-2):83-90
A dilute micellar solution of poly(oxyethylene) 4-nonylphenyl ether with oxyethylene units 7.5 (PONPE-7.5) was separated into two phases (aqueous and surfactant phases) at room temperature. The partition constants of several chelating reagents and their metal chelates between the two phases were determined at 293 K and ionic strength 0.1 (NaClO4). The partition constants of the neutral metal chelates depend on the kind of metal ions and were considerably smaller than those expected from the regular solution theory. These facts suggested that the chelates were incorporated into a hydrocarbon environment in the surfactant phase, whereas the chelating reagents were distributed in the poly(oxyethylene) part of PONPE-7.5. A brief review was also presented on the analytical applications to the extraction of metal ions and organic compounds. 相似文献