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采用毛细管气相色谱法(GC)测定了二乙基二硫的含量.结果表明,二乙基二硫含量在0.010.4g/L范围内具有良好的线性关系,平均回收率为99.91%;该方法简便、准确、重复性好,可方便地用于二乙基二硫含量的测定. 相似文献
104.
Jingang Fang Baowei Wang Zhenhua Li Genhui Xu 《Reaction Kinetics and Catalysis Letters》2003,80(2):293-301
The synthesis of diethyl oxalate from ethyl nitrite and carbon monoxide in gaseous phase has been studied at atmospheric pressure.
Kinetics of coupling - regeneration reaction has been determined and the optimization of the reaction has been simulated.
The influences of gas impurities has also been studied. Scale-up circulating shows that the concentrate and selectivity were
stable in the product and the process is suitable for industrial production.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Visible-light transparent high-quality substrate-supported poly(2,3-benzofuran) (PBF) film has been successfully electrosynthesized by direct anodic oxidation of 2,3-benzofuran on stainless steel sheet in boron trifluoride diethyl etherate (BFEE) containing 10% poly(ethylene glycol) (PEG) with molar mass of 400 (by volume). The oxidation potential of 2,3-benzofuran in this medium was measured to be only 1.0 V vs. SCE, which is lower than that determined in acetonitrile + 0.1 M Bu4NBF4 (1.2 V vs. SCE). The PBF films obtained in this media showed good electrochemical behaviors and good thermal stability with conductivity of 10−2 S cm−1, and the doping level of as-prepared PBF films was determined to be only 8.9%. The structure and morphology of the polymer were investigated by UV-vis, infrared spectroscopy and scanning electron microscopy (SEM), respectively. To the best of our knowledge, this is the first case for the syntheses of PBF films. 相似文献
107.
从磷硅试剂合成烃基膦酯类化合物 总被引:1,自引:1,他引:0
本文报导三甲基硅氧基亚磷酸酯(一种活性较高的磷硅试剂)与醛酮反应而获得十四个二乙基三甲硅氧基烃基膦酸酯。产物结构经IR,~1HNMR,~(31)PNMR,MS测试和元素分析表征;对反应机理作了初步讨论。 相似文献
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K.D. Belfield M.V. BondarO.V. Przhonska K.J. SchaferW. Mourad 《Journal of luminescence》2002,97(2):141-146
Investigations of the absorption, steady-state fluorescence, excitation and excitation anisotropy properties of several fluorene derivatives, (7-benzothiazol-2-yl-9,9-didecylfluoren-2-yl)-diphenylamine, 9,9-didecyl-2,7-bis-(N,N-diphenylamino)fluorene and {4-[2-(7-diphenylamino-9,9-diethylfluoren-2-yl)vinyl]phenyl}phosphoric acid diethyl ester, in liquid solutions have been conducted. Spectral characteristics of these compounds, including fluorescence quantum yields, were measured in acetonitrile, methylene chloride, tetrahydrofuran and hexane at room temperature. Excitation anisotropy spectra provided a means to determine the nature of the short wavelength absorption bands as an electronic transition into a higher excited singlet state. It was found that excitation spectra in the short wavelength region do not correspond to the absorption bands that are correlated with the wavelength dependence of the fluorescence quantum yields. Major reasons of such spectral behavior are discussed. 相似文献
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