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1.
2.
D. Li K. Imasaki S. Miyamoto S. Amano T. Mochizuki 《Journal of Infrared, Millimeter and Terahertz Waves》2004,25(7):1069-1073
We studied on realization of short pulse gamma ray and X-ray simultaneously induced by a femtosecond laser on NewSUBARU storage ring. Based on the fact that the transverse dimensions of electron beam are much shorter than the longitudinal one, the laser light is arranged to collide the electron beam at a right angle to generate femtosecond pulse gamma ray, furthermore, the modulated part of the electron bunch gives rise to short pulse X-ray by synchrotron radiation from a downstream bending magnet. The temporal characteristic of the radiation is analyzed in this paper, as well as the performances are estimated. 相似文献
3.
Tsujimura T. Tokuhiro O. Morooka M. Miyamoto T. Miwa K. Yoshimura Y. Andry P. Libsch F. 《Electron Devices, IEEE Transactions on》2002,49(4):576-583
The leakage mechanism for a top-gate thin-film transistor (TFT) produced using the fewest process steps in the industry is analyzed in order to achieve a high-contrast liquid crystal display (LCD). Using a T-shaped TFT structure, the OFF and ON channel lengths are defined independently, so that the leakage can be reduced with no ON current decrease 相似文献
4.
Wakejima A. Matsunaga K. Okamoto Y. Ando Y. Nakayama T. Miyamoto H. 《Electronics letters》2005,41(25):1371-1372
A single-ended amplifier using small packaged GaN-FETs exhibits a record 2.14 GHz W-CDMA output power. The amplifier, composed of paralleled 48 mm gate periphery FET die, delivers a peak saturated output power of 371 W with a linear gain of 11.2 dB at a drain voltage of 45 V under 2.14 GHz 3GPP W-CDMA signal input. The output power density (output power/package size) of 1.1 W/mm/sup 2/ is twice as high as that of the existing over 300 W GaAs-FET amplifiers. A low 5 MHz offset ACLR of -36 dBc with a drain efficiency of 24% is also obtained at 8 dB power back off from the saturated output power. 相似文献
5.
Noda K. Tatsumi T. Uchida T. Nakajima K. Miyamoto H. Chenming Hu 《Electron Devices, IEEE Transactions on》1998,45(4):809-814
A simple fabrication technology for delta-doped MOSFETs, named post-low-energy implanting selective epitaxy (PLISE) is presented. The PLISE technology needs no additional photo-lithography mask, deposition step or etching step even for CMOS devices. The only additional step is growing undoped epitaxial channel layers by UHV-CVD after the channel implantation. With this technology, delta-doped NMOSFETs with 0.1-μm gate length were successfully fabricated. By optimizing the epi-layer thickness and the channel doping level, short-channel effects are suppressed enough to achieve 0.1-μm gate length. Moreover, the junction capacitance at zero bias is reduced by 50% 相似文献
6.
T. Mihara K. Miyamoto M. Kida T. Sasaki N. Aoki Y. Ochiai 《Superlattices and Microstructures》2003,34(3-6):383
A multiwall carbon nanotube crossroads has been fabricated by a manipulation technique using a glass microcapillary, and the low temperature transport properties investigated. The two-terminal conductance of an individual tube shows Tomonaga–Luttinger liquid behavior G∝Tα at high temperature and dI/dV ∝V α at low temperature. However, no evidence of such a power-law behavior is obtained in the four-terminal conductance at the junction, where the conductance shows an almost metallic behavior ‘corrected’ by weak localization. Weak localization would essentially appear in electron states at the junctions of MWNTs. 相似文献
7.
Adachi I Aihara H Dijkstra HB Enomoto R Fujii H Fujii K Fujii T Fujimoto J Fujiwara N Hayashii H Higashi S Iida N Imanishi A Ikeda H Ishii T Itoh R Iwasaki H Iwata S Kajikawa R Kamae T Kato S Kawabata S Kichimi H Kishida T Kobayashi M Kuroda S Kusuki N Maruyama A Maruyama K Masuda H Matsuda T Miyamoto A Morimoto T Nakamura K Nitoh O Noguchi S Ochiai F Okuno H Okusawa T Ohshima T Ozaki H Sato T Sai F Shimonaka J Shimozawa K Shirahashi A Sugahara R Sugiyama A Suzuki S Suwada T Takahashi K 《Physical review letters》1988,60(2):97-100
8.
New triterpenes from a Chinese medicine, goreishi 总被引:1,自引:0,他引:1
A Numata C Takahashi T Miyamoto M Yoneda P M Yang 《Chemical & pharmaceutical bulletin》1990,38(4):942-944
Besides serratagenic acid, three new ursane-type triterpenes, named goreishic acids I (1), II (2), and III (3), were isolated from a Chinese medicine, Goreishi (the feces of Trogopterus xanthipes Milne-Edwards). The structures of 1, 2 and 3 were respectively determined as 2 alpha,3 beta-dihydroxyursa-12,18-dien-28-oic acid, 2 alpha,3 beta-dihydroxy-23-norursa-12,18-dien-28-oic acid and 2 alpha,3 beta-dihydroxy-24-norursa-12,18-dien-28-oic acid on the basis of spectroscopic evidence. 相似文献
9.
alpha-Tocopherol (alpha-Toc) was solubilized in aqueous solutions using 13 solubilizing agents and the products of oxidation by oxygen in the presence and the absence of Cu(II) were analyzed by HPLC. In the presence of Cu(II), the oxidation was accelerated and 5-formyl-7,8-dimethyltocol and alpha-tocoquinone were the major oxidation products. Their yields greatly increased in the presence of Cu(II). The yields and the rates of formation of the products were dependent on the properties of solubilizing agents and other conditions as well as the presence of Cu(II) or other metal ions. It is suggested that slight changes in the structure of the solubilizing agents affect the course of the reaction. 相似文献
10.
Diaminomethylenehydrazones 1 of aromatic and aliphatic carbonyl compounds react with dimethyl acetylenedicarboxylate (DMAD) at room temperature to give four types of heterocycles, (5-oxoimidazolin-4-ylidene) acetates 2, 3 and 6 , (2-imino-5-oxoimidazolidin-4-ylidene) acetate 4 and 6-oxo-1,6-dihydropyrimidine-4-carboxylates 5 according to the substitution patterns of 1 in moderate to high yields. Amino (N,N-dimethylamino)methylenehydrazones of ketones give exclusively (5-oxoimidazolin-4-yl-idene) acetates, both (Z)- and (E)-isomers 2 and 3 about the exocyclic alkenic linkage, with the (Z)-isomer 2 generally being predominant, while those of aldehydes give 5 . Diamino- and amino (N-methylamino)methylenehydrazones produce 5 and/or 6 and di (N-methylamino) methylenehydrazone gives (2-imino-5-oxoimidazolidin-4-ylidene) acetate 4 as the sole cyclized product. 相似文献