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991.
To understand a mechanism of spark transients, using a 12-GHz digital oscilloscope, we measured discharge currents due to a finger touch through a hand-held metal bar or a fingertip with an aluminum foil attachment from a charged human body with a charge voltage of 600 V. As a result, we found that the hand-held metal bar and aluminum foil attachment produce a one-shot discharge current with steeply rising time shorter than a 100 ps, while the fingertip without any aluminum foil attachments produces multiple-shot discharge currents with gently rising time larger than a 100 ps and significantly low amplitudes. 相似文献
992.
Naoto Matsuo Yasunori Kitagawa Yoshinori Takami Junya YamauchiHiroki Hamada Tadaki Miyoshi 《Superlattices and Microstructures》2000,28(5-6)
The effects of the off-set energy between the dielectric films which are formed at the both edges of the channel and the Si substrate on the electrical characteristics are examined for the Si resonant tunneling MOST (SRTMOST). The barrier height of the dielectric films has a great influence on the operation of the SRTMOST. The relationship between the transmission coefficient and the off-set energy of the double barrier/Si is calculated as well as the relationships between the gate-off currents, the transition time from the source to the drain and the off-set energy. It was found that the critical off-set energy of dielectric film/Si is approximately 1.0–1.5 eV. 相似文献
993.
Toshiyasu Inuzuka Keita Yamamoto Arihiro Iwasaki Osamu Ohno Kiyotake Suenaga Yoshinori Kawazoe Daisuke Uemura 《Tetrahedron letters》2014
Three novel compounds, yoshinones A, B1, and B2, were isolated from the marine cyanobacterium Leptolyngbya sp., and their structures were elucidated by NMR spectral analysis. Yoshinone A, but not yoshinone B1 or B2, inhibited the differentiation of 3T3-L1 cells into adipocytes. In addition, yoshinone A did not exhibit cytotoxicity, suggesting that yoshinone A may be useful in studies on the treatment of obesity. 相似文献
994.
Reiko Ando Yoshinori Makino Tomohide Tamura Noboru Yamamoto Rena Nishigaki Takehiro Kimura Nobuaki Yokote Hiroshi Yamamoto 《Biomedical chromatography : BMC》2010,24(3):301-306
A simple and sensitive high‐performance liquid chromatographic (HPLC) method was developed for determination of amrubicin and its metabolite amrubicinol in human plasma. After protein precipitation with methanol without evaporation procedure, large volume samples were injected and separated by two monolithic columns with a guard column. The mobile phase consisted of tetrahydrofuran–dioxane–water (containing 2.3 mM acetic acid and 4 mM sodium 1‐octanesulfonate; 2:6:15, v/v/v). Wavelengths of fluorescence detection were set at 480 nm for excitation and 550 nm for detection. Under these conditions, linearity was confirmed in the 2.5–5000 ng/mL concentration range of both compounds. The intra‐ and inter‐day precision and intra‐ and inter‐day accuracy for both compounds were less than 10%. The method was successfully applied to a clinical pharmacokinetic study of amrubicin and amrubicinol in cancer patients. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
995.
Yoshinori Tominaga Kenichi Nomoto Noriko Yoshioka 《Journal of heterocyclic chemistry》2001,38(5):1135-1141
Reaction of 3‐amino‐3‐methylthio‐2‐cyanoacrylonitrile (1) with excess dimethyl acetylenedi‐carboxylate(DMAD) in the presence of potassium carbonate in dimethyl sulfoxide gave a novel tricyclic heterocycle, hexamethyl lH‐1,4,7‐triazaphenalene‐2,3,5,6,8,9‐hexacarboxylate ( 5a ). When one equivalent of DMAD was used in this reaction, dimethyl 4‐amino‐3‐cyano‐2‐methylthiopyridine‐5,6‐dicarboxylate ( 3a ), a key intermediate of 5a , was obtained. 相似文献
996.
Yoshinori Tominaga Satoshi Takada Shinya Kohra Yasumitsu Shigemitsu 《Journal of heterocyclic chemistry》2001,38(5):1143-1151
3‐[(Trimethylsilylmethylamino)(methylthio)]methylene‐2‐coumaranone ( 4a ) and 1‐methyloxindole ( 4b ), readily prepared by reactions of the corresponding bis(methylthio)methylene heterocyclic compounds ( 2a, b ), with (trimethylsilylmethyl)amine (3), were found to be synthetic equivalents of heterocyclic alkylidene‐azomethine ylides. Reactions of 4a, b with reactive heterodipolarophiles such as aldehydes and ketones and reactive alkenes in the presence of cesium fluoride gave the 1,3‐dipolar cycloadducts, 3‐(2‐oxazoli‐dinylidene)‐oxindole and ‐coumaran‐2‐one derivatives ( 8a‐j, 9a‐h ), as well as pyrrolylidenecoumaran‐2‐one and oxindole derivatives ( 12‐15,17,18 ), via the 1,3‐elimination of (methylthio)trimethylsilane. 相似文献
997.
Kenichi Yaoita Kazuhiko Tsuji Yoshinori Katayama Motoharu Imai Jian-Qiang Chen Takumi Kikegawa Osamu Shimomura 《Journal of Non》1992,150(1-3):25-28
The structure factor, S(Q), of liquid bismuth near the melting temperature at pressures up to 7.3 GPa has been measured by an energy-dispersive X-ray diffraction method, using synchrotron radiation and a cubic-type high-pressure apparatus. The structure of liquid bismuth at atmospheric pressure shows similarity to high-pressure solid phases rather than to the atmospheric-pressure phase. With increasing pressure below 7 GPa, S(Q) changes continuously, becoming simpler in form and with the first peak becoming higher. In addition, the structure factor obtained at 7.3 GPa is totally different from those at lower pressures. It has extremely sharp peaks located at regular intervals in Q. It is concluded that liquid bismuth changes its structure drastically between 6 and 7 GPa. A model for the structure of liquid bismuth above this structural change is proposed. 相似文献
998.
Yoshinori Hamahata 《manuscripta mathematica》1993,79(1):307-327
We define the tensor product ϕ ⊗ ψ and relatedt-modules Sym2(ϕ), and ∧2(ϕ) for Drinfeld modules ϕ, ψ defined over the rational function fieldK=F
q
(T), and describe thev-adic Tate modules of theset-modules by using those of ϕ, ψ. 相似文献
999.
The bi-ionic potential generated across a standard cation exchange membrane was investigated in a mono-divalent bi-ionic system. Applying Henderson's theory to the film layer, the Nernst—Planck equation was solved in the film layer as well as in the membrane. The observed potentials were compared with the theoretically predicted values from parameters such as bulk concentrations, diffusion coefficients in the membrane and in solution, exchange capacity, corrected molar selectivity coefficient, and film layer thickness. The calculated potentials were not always in agreement with the experimental values, but reproduced properly the trend of potential change with concentration and stirring rate. The constituent potentials, i.e. the diffusion potentials in the film layer and in the membrane and the interfacial potentials, are also discussed. In the sodium—calcium bi-ionic system, the primary contribution to the total membrane potential was not the diffusion potential in the film layers and in the membrane, but the sum of two interfacial potentials. p]In the case of membrane-diffusion control, the bi-ionic potential was confirmed to follow the equation of Helfferich. 相似文献
1000.
Yoshinori Tominaga Shozo Hidaki Yoshiro Matsuda 《Journal of heterocyclic chemistry》1987,24(2):519-520
Fused thiabenzene oxide, 2-methyl-4-methylthiobenzo[b]thieno[3,2-c]thiapyran 2,5,5-trioxide (2) was synthesized by the reaction of 2,3-dihydro-2-bis(methylthio)methylene-3-oxobenzo[b]thiophene 1,1-dioxide (1) with trimethyl sulfoxonium iodide in the presence of sodium hydride in tetahydrofuran. Similarly, fused azathiabenzene oxide, 2-methyl-4-methylthiobenzo[b]thieno[2,3-c][1,2]thiazine 2,5,5-trioxide (3) was prepared from 1 and sulfoximine in good yield. 相似文献