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171.
Ida K Funaba H Kado S Narihara K Tanaka K Takeiri Y Nakamura Y Ohyabu N Yamazaki K Yokoyama M Murakami S Ashikawa N deVries PC Emoto M Goto M Idei H Ikeda K Inagaki S Inoue N Isobe M Itoh K Kaneko O Kawahata K Khlopenkov K Komori A Kubo S Kumazawa R Liang Y Masuzaki S Minami T Miyazawa J Morisaki T Morita S Mutoh T Muto S Nagayama Y Nakanishi H Nishimura K Noda N Notake T Kobuchi T Ohdachi S Ohkubo K Oka Y Osakabe M Ozaki T Pavlichenko RO Peterson BJ Sagara A Saito K Sakakibara S Sakamoto R 《Physical review letters》2001,86(23):5297-5300
Recent large helical device experiments revealed that the transition from ion root to electron root occurred for the first time in neutral-beam-heated discharges, where no nonthermal electrons exist. The measured values of the radial electric field were found to be in qualitative agreement with those estimated by neoclassical theory. A clear reduction of ion thermal diffusivity was observed after the mode transition from ion root to electron root as predicted by neoclassical theory when the neoclassical ion loss is more dominant than the anomalous ion loss. 相似文献
172.
Narihara K Watanabe KY Yamada I Morisaki T Tanaka K Sakakibara S Ida K Sakamoto R Ohyabu N Ashikawa N Emoto M Funaba H Goto M Hayashi H Idei H Ikeda K Inagaki S Inoue N Kaneko O Kawahata K Kobuchi T Komori A Kubo S Kumazawa R Masuzaki S Miyazawa J Morita S Motojima O Murakami S Muto S Mutoh T Nagayama Y Nakamura Y Nakanishi H Nishimura K Noda N Notake T Ohdachi S Oka Y Ohkubo K Osakabe M Ozaki S Peterson BJ Sagara A Saito K Sasao H Sasao M Sato K Sato M Seki T Shimozuma T Shoji C Sudo S 《Physical review letters》2001,87(13):135002
It was observed that the vacuum magnetic island produced by an external error magnetic field in the large helical device shrank in the presence of plasma. This was evidenced by the disappearance of flat regions in the electron temperature profile obtained by Thomson scattering. This island behavior depended on the magnetic configuration in which the plasmas were produced. 相似文献
173.
Dispersion resulting from phase and amplitude errors in arrayed-waveguide grating multiplexers-demultiplexers 总被引:1,自引:0,他引:1
We report dispersion resulting from phase and amplitude errors in arrayed-waveguide grating (AWG) multiplexers-demultiplexers. We measure the phase- and amplitude-error distributions of two different types of AWG and discuss their effects on the dispersion. The results show that the origin of the dispersion in the AWG is the low-order Fourier components of the symmetric phase and the antisymmetric amplitude errors. We also discuss the dependence of the dispersion on the passband shape in the presence of the same fabrication errors. 相似文献
174.
Real three-dimensional microstructures fabricated by photopolymerization of resins through two-photon absorption 总被引:9,自引:0,他引:9
Sun HB Kawakami T Xu Y Ye JY Matuso S Misawa H Miwa M Kaneko R 《Optics letters》2000,25(15):1110-1112
Effective energy windows for two-photon absorption (TPA) photopolymerization of resins were investigated and, with a properly selected laser pulse energy, exquisite three-dimensional (3D) microstructures with submicrometer spatial resolution were achieved. The results show the inherent utility of TPA in the fabrication of real 3D patterns. In particular, we propose and utilize a resin pre-exposure technique by which freely movable components affixed to an axle are built, demonstrating a new application of TPA in laser microfabrication. 相似文献
175.
Density functional calculations have been used to investigate the (0 0 1) surface of cubic SrZrO3 with both SrO and ZrO2 termination. Surface structure and electronic structure have been obtained. The SrO surface is found to be similar to its counterpart in SrTiO3, while there are marked differences between the ZrO2 and TiO2 terminations in SrZrO3 and SrTiO3, respectively, concerning surface relaxation and rumpling. For the ZrO2-terminated surface of SrZrO3, the covalency of the interaction between the outmost Zr and the O beneath is enhanced as a result of their bond contraction. The band gap reduction and the presence of the surface states are also discussed in relation with the behavior of the electrostatic potential. 相似文献
176.
Hidemasa Hidaka Masao Hirayama Kazuhiko Yamada 《Journal of carbohydrate chemistry》2013,32(4):509-522
I. INTRODUCTION Recently the study of oligosaccharides has been extensively pursued in Japan after the findings of the remarkable biofunctions and usefulness of fructooligosac-charides for human health, improving the intestinal microflora and importance in livestock nutrition. 相似文献
177.
Satoru Tamura Masafumi Kaneko Susumu Tanimura Nobutoshi Murakami 《Tetrahedron letters》2010,51(13):1678-3843
A new polyketide peumusolide A was disclosed as an unprecedented NES non-antagonistic inhibitor for nuclear export of MEK, a promising scaffold for antitumor agents with novel mechanism of action, from Peumus boldus Molina. The absolute stereostructure as well as optical purity was established by use of the two synthesized enantiomeric model lactones. In addition, the Δε values in their CD spectra were demonstrated to be the conclusive index for determination of not only configuration at C-3 but also optical purity of natural congeneric polyketides. Peumusolide A was revealed to show NES non-antagonistic action by the biotinylated probe and to inhibit proliferation of MEK-activated tumor cells selectively. 相似文献
178.
179.
Masao Yamazaki 《Mathematische Nachrichten》1987,133(1):297-315
In this paper we consider pseudodifferential operators associated with symbols satisfying estimates of product type, and give some sufficient conditions for the operators to be bounded on BESOV spaces and on TRIEBEL —LIZORKIN spaces of product type corresponding to the above estimates. In the proof we use the characterization of these spaces by approximation by entire functions. 相似文献
180.
Liang Bao Liu Noriko Murakami Masao Sumita Keizo Miyasaka 《Journal of Polymer Science.Polymer Physics》1989,27(12):2441-2450
The effect of molecular weight distribution (MWD) on the ultradrawability and mechanical properties of solution-cast films of ultrahigh-molecular-weight polyethylene (UHMW-PE) has been investigated using tensile and dynamic mechanical measurements. The MWD has a marked effect on ultradrawability and thus on the ultimate mechanical properties such as the tensile modulus. It is proposed that UHMW-PE with a narrow MWD(N-PE) attains the ultimate structure at a lower draw ratio than UHMW-PE with a broad MWD(B-PE) because of the existence in the latter of less fully extended intercrystalline tie chains. It is found that, at the same drawing temperature (100°C), N-PE shows a higher modulus than B-PE at draw ratios up to 150 x, which is assumed to be the ultimate value for N-PE. 相似文献