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81.
Yoshinori Kamiya Yasutoshi Naito Takuji Hirose Keishin Mizoguchi 《Journal of Polymer Science.Polymer Physics》1990,28(8):1297-1308
Sorption of N2, O2, Ar, CH4, CO2, C2H4, and C2H6 in poly (dimethyl siloxane) liquid and rubber and the dilation of the polymers due to sorption of the gases are studied at 25°C under pressures up to 50 atm. In the liquid, the sorption isotherms for low-solubility and high-solubility gases are described by Henry's law and the Flory–Huggins equation, respectively. Gas sorption in the rubber, which contains a 29 wt % silica filler, follows the dual-mode sorption model, though marked hysteresis is observed in the sorption of O2 and CH4. The dilation isotherms increase linearly or exponentially in both polymers with increasing pressure. Considering that gas molecules adsorbed into micropores of the filler particles do not participate in the dilation, partial molar volumes of the dissolved gases in the rubber are determined from data of sorption and dilation. The values are nearly equal to the partial molar volumes in the liquid (48–60 cm3/mol). 相似文献
82.
Masafumi UedaYuki Ikeda Aoi SatoYuta Ito Maiko KakiuchiHiroko Shono Tetsuya MiyoshiTakeaki Naito Okiko Miyata 《Tetrahedron》2011,67(25):4612-4615
A facile and practical synthesis of 3,5-disubstituted isoxazoles via a silver-catalyzed cyclization and subsequent protonation of alkynyl oxime ethers has been developed. The methodology was successfully applied to the synthesis of a biologically active isoxazolecarboxylic acid. 相似文献
83.
Contamination of the exterior surface of vials of cytostatic drugs by the drugs themselves is a potential hazard to human health. This study developed a validated method using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) for the determination of contamination of the exteriors of vials of cisplatin and carboplatin. Large Alpha® sampling swabs were employed to wipe the vial exterior. Cisplatin or carboplatin and gold(III) as an internal standard were derivatized by N,N-diethyldithiocarbamate (DDTC). Pt(DDTC)3+ and Au(DDTC)2+ were monitored by the respective transitions of m/z 639.3-490.9 and 493.0-345.0, respectively. Each separation was completed within 9 min using a 3 μm particle ODS-column. Calibration curves for cisplatin and carboplatin were linear over concentration ranges of 30-10,000 and 30-30,000 pg vial−1, respectively. The accuracies and precisions were 96.1-102.5% and within 8.2% for intra-assay and 99.6-103.3% and within 7.6% for inter-assay, respectively. Their lower limit of quantification was 30 pg vial−1. Amounts of 0.17-17.0 ng vial−1 as cisplatin and 0.48-794 ng vial−1 as carboplatin were detected from the exterior surface of the vials. This validated method using LC-ESI-MS/MS for the determination of platinum anticancer drugs is helpful for monitoring contamination of the exterior surface of drug vials. 相似文献
84.
Manabu Naito 《Journal of Mathematical Analysis and Applications》2011,381(1):315-327
In this paper second order quasilinear ordinary differential equations are considered, and a necessary and sufficient condition for the existence of a slowly growing positive solution is established. Moreover, the precise asymptotic forms as t→∞ of slowly growing positive solutions and slowly decaying positive solutions are obtained. 相似文献
85.
Ueda M Sugita S Aoi N Sato A Ikeda Y Ito Y Miyoshi T Naito T Miyata O 《Chemical & pharmaceutical bulletin》2011,59(9):1206-1208
The synthetic utility of N-alkoxyimidoyl halides is demonstrated using the palladium-catalyzed cross-coupling reaction. The Sonogashira and Suzuki-Miyaura coupling reactions of N-alkoxyimidoyl bromides produced versatile ketoxime ethers in good to excellent yields. A one-pot reaction of the imidoyl bromides with arylboronic acid and allylmagnesium bromide to produce N-arylamines via Suzuki-Miyaura coupling followed by domino reaction involving sequential addition-eliminative rearrangement-addition reactions was developed. 相似文献
86.
Kitamura C Takenaka A Kawase T Kobayashi T Naito H 《Chemical communications (Cambridge, England)》2011,47(23):6653-6655
Tetracene octaesters, which were prepared by twofold [2+2+2] cocyclization, were isolated as red, orange, and orange-yellow solids for the methyl, ethyl, and propyl ester derivatives, respectively. X-Ray crystallographic analysis reveals that the difference in solid-state color arises owing to differences in molecular packing. 相似文献
87.
Muneyuki Tsuda 《Surface science》2006,600(18):3992-3994
We investigate O2 binding to cytochrome c oxidase (CcO)-inspired nanomaterials using ab initio density functional calculations. We consider iron-porphyrin (FeP) and copper-(imidazole)3 [Cu(Im)3] as a representative of the active binuclear center, and explore the effect of the Cu(Im)3 on the FeP-O2 adduct in relation to the geometric, vibrational, electronic and energetic properties. We find that the Cu(Im)3 induces the weak O-O and Fe-O bonds mainly because of the electron transfer to the O2 and the spin polarization of the Fe and O2 by bridging the O2 between the Fe and Cu, possibly resulting in the facile O2 dissociation. 相似文献
88.
Here we summarize multi-terabit long-haul transmission experiment and distributed Raman amplification (DRA) technologies. As well, we investigate the configuration of dispersion-managed fibers for the DRA-based system from the viewpoint of the fiber non-linear effect and required pumping power. 相似文献
89.
Irradiation of graphite fluoride with electron beams has been carried out on a electron probe microanalyzer. Radiation-induced decomposition took place predominantly instead of thermal decomposition. The decomposition tended to occur in the following order: powdery (CF)n, white flaky (CF)n, and (CF2F)n. The kinetics of the decomposition reaction induced by electron beams was evaluated by the ZAF correction of the measured intensities of F K- and C K-emission bands. It was found that the kinetic of the decomposition of graphite fluoride was of Avrami-Erofejev type; the rate equations were for (CF)n and -ln(1?α)=kt2 for (C2F)n. An application to the electron microbeam processing of graphite fluoride was suggested in relation to its unique physicochemical properties. 相似文献
90.
S Sugai T Okazaki Y Kajiwara T Kanbara Y Naito S Yoshida S Akaboshi S Ikegami Y Kamano 《Chemical & pharmaceutical bulletin》1985,33(5):1889-1898