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1.
Cho T Yoshida M Kohagura J Hirata M Numakura T Higaki H Hojo H Ichimura M Ishii K Islam KM Itakura A Katanuma I Nakashima Y Saito T Tatematsu Y Yoshikawa M Kojima Y Tokioka S Yokoyama N Tomii Y Imai T Pastukhov VP Miyoshi S;GAMMA Group 《Physical review letters》2005,94(8):085002
Vortexlike turbulent structures in hot-ion mode plasmas with several keV are observed in the case with a radially produced weak shear of electric fields E(r). However, a strong E(r) shear formation due to a high ion-confining potential phi(c) production clears up these vortices together with plasma-confinement improvement and disappearance of both drift-wave and turbulencelike Fourier spectral signals. These findings are based on three-time progress in phi(c) in comparison to phi(c) attained 1992-2002. The significant advance of phi(c) is well extended in line with proposed potential-formation physics scalings. 相似文献
2.
We report the time-dependent intensities for the photoluminescence (PL) at various temperatures (10 K ? T ? 300 K) in amorphous GeS2, which is known to exhibit not only PL fatigue but also PL recovery behavior. A difference in reversibility in fatigue-recovery process was found between room temperature (RT) and those at 110 K or below. Another small band of PL was also observed at 10 K or less, which also showed a time-dependence in intensity. A functional form to describe the time dependence was adopted based on a simplified model which have been obtained in a previous study and extended to describe the fatigue-recovery behaviors for all temperature range which have measured below RT. 相似文献
3.
Matsumoto T Furutachi H Kobino M Tomii M Nagatomo S Tosha T Osako T Fujinami S Itoh S Kitagawa T Suzuki M 《Journal of the American Chemical Society》2006,128(12):3874-3875
A discrete (mu-eta2:eta2-peroxo)Cu(II)2 complex, [Cu2(O2)(H-L)]2+, is capable of performing not only intramolecular hydroxylation of a m-xylyl linker of a dinucleating ligand but also intermolecular epoxidation of styrene via electrophilic reaction to the C=C bond and hydroxylation of THF by H-atom abstraction. 相似文献
4.
Tsuneo Itoh Ikuko Fujii Yasuo Tomii Ichiro Ishikawa Hamo Ogura Yoshihisa Mizuno Norio Kawahara 《Journal of heterocyclic chemistry》1987,24(5):1453-1455
An improved and efficient synthesis of 1,3-dialkylpyrido[2,3-d]pyrimidine-2,4-(1H,3H)-diones from 6-methylaminouracils and methyl propiolate or diethyl ethoxymethylenemalonate is described. 相似文献
5.
Matsuoka M Segawa J Amimoto I Masui Y Tomii Y Kitano M Kise M 《Chemical & pharmaceutical bulletin》1999,47(12):1765-1773
A series of 7-substituted-6-fluoro-1-fluoromethyl-4-oxo-4H- [1,3]thiazeto[3,2-a]quinoline-3-carboxylic acid derivatives (2a-1) was prepared and evaluated for antibacterial activity. These compounds were obtained by deacylation of 4-benzoyloxy-2-(1-chloro-2-fluoroethyl)thio-6,7- difluoroquinoline-3-carboxylate (10) and subsequent intramolecular cyclization followed by substitution with cyclic amines and then hydrolysis. The intramolecular cyclization reaction of 18, one of the diastereomers (17, 18) revealed that the cyclization reaction proceeded through an inversion to afford (-)-11a in good chemical and optical yield. The enantiomers of 2a were prepared from the enantiomers of 11a, which were obtained by the optical resolution of the racemate using high-performance liquid chromatography (HPLC). Compounds 2a,b showed excellent in vitro and in vivo antibacterial activity against both gram-negative and gram-positive bacteria including quinolone and Methicillin-resistant Staphylococcus aureus. 相似文献
6.
We have measured the angle-resolved intensity and speed distributions of C2H6 scattered from LiF(0 0 1) along the [1 0 0] azimuthal direction, the largest structural corrugation direction, to investigate the effect of the molecular anisotropy on the gas–surface interaction at the corrugated surface. While clear rainbow feature is observed in the mean energy angular distribution, no rainbow feature is detected in the intensity angular distribution. From the comparisons of the obtained results to the calculated predictions based on the simple classical theory of the ellipsoid-washboard model, the effect of the molecular anisotropy is found to play a crucial role in the rainbow feature. With an increase in the extent of the molecular anisotropy such as that of C2H6 as compared with rare gas atoms, the integration of the intensity angular distributions for various molecular orientations results in the smearing of the rainbow feature on the corrugated surface. The rainbow scattering in the mean energy angular distribution, however, is not completely smeared out. 相似文献
7.
Cho T Kohagura J Numakura T Hirata M Higaki H Hojo H Ichimura M Ishii K Islam KM Itakura A Katanuma I Minami R Nakashima Y Saito T Tatematsu Y Watanabe O Yoshikawa M Kojima A Miyake Y Miyata Y Shimizu K Tomii Y Yoshida M Sakamoto K Imai T Pastukhov VP Miyoshi S;GAMMA Group 《Physical review letters》2006,97(5):055001
Off-axis electron-cyclotron heating in an axisymmetric barrier mirror produces a cylindrical layer with energetic electrons, which flow through the central cell and into the end region. The layer, producing a localized bumped ambipolar potential Phi(C), forms a strong shear of radial electric fields E(r) and peaked vorticity with the direction reversal of E(r)xB sheared flow near the Phi(C) peak. Intermittent vortexlike turbulent structures near the layer are suppressed in the central cell by this actively produced transverse energy-transport barrier; this results in T(e) and T(i) rises surrounded by the layer. 相似文献
8.
Masakazu Nakamura Hirokazu Ohguri Naoyuki Goto Hiroshi Tomii Mingsheng Xu Takashi Miyamoto Ryousuke Matsubara Noboru Ohashi Masaaki Sakai Kazuhiro Kudo 《Applied Physics A: Materials Science & Processing》2009,95(1):73-80
Extrinsic factors to disturb the carrier transport in pentacene field-effect transistors (FETs), as a representative of the
high-mobility organic FETs (OFETs), have been comprehensively analyzed by using atomic-force-microscope potentiometry (AFMP),
microscopic four-point-probe field-effect transistor (MFPP-FET) measurement, and other techniques. In the first part, by mainly
using AFMP as a powerful tool to reveal the potential distribution in working OFETs, we show how and how much the formation
of source/drain electrodes influences the apparent field-effect mobility both for top- and bottom-contact configurations.
In the second part, we show the influence of irregular grain structures and regular grain boundaries. The films grown both
at very low and high temperature ranges contain distinctive insulating parts, which make the apparent mobility very low. Within
the moderate growth temperature range, the intrinsic field-effect mobility obtained by MFPP-FET measurement is proportional
to the average grain size. This behavior is well explained by the polycrystalline model with the diffusion theory. According
to the observations in this work, it is obvious that these extrinsic limiting factors must be carefully excluded to discuss
the intrinsic mechanism of the carrier transport in OFETs. 相似文献
9.
Tsuneo Itoh Ikuko Fujii Yasuo Tomii Haruo Ogura Yoshihisa Mizuno Norio Kawahara 《Journal of heterocyclic chemistry》1987,24(4):1215-1217
On the treatment of 1,3-dialkyl-6-alkylaminouracil (1) with dimethyl acetylenedicarboxylate (DMAD), we were able to develop a new synthesis of deazapurine (pyrrolo[2,3-d]pyrimidine, 4) , and proposed the plausible mechanism for the formation of 3 and 4 from the adduct [dimethyl 2-(1,3-dialkyl-6-alkylamino-2,4-dioxopyrimidin-5-yl)fumarate, 2] of 1 with DMAD. 相似文献
10.
Yasuyoshi Miki Osamu Tomii Hayami Nakao Mayumi Kubo Hiroko Hachiken Shoji Takemura Masazumi Ikeda 《Journal of heterocyclic chemistry》1988,25(1):327-331
Treatment of 3-(or-hydroxybenzyl)pyrazolo[1,5-a]pyridines with trifluoroacetic acid in dichloromethane resulted in the formation of pyrazolo[1,5-a]pyridines, bis[α-(pyrazolo[1,5-a]pyrid-3-yl)benzyl] ethers, and phenylbis(pyrazolo[1,5-a]pyrid-3-yl)methanes, depending upon the presence or absence of the substituents at the 2- and/or 4-positions and the reaction conditions employed. 相似文献