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141.
Kazuya Uenishi Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2005,43(19):4422-4430
A novel 5‐membered cyclic dithiocarbonate (DTC) having a siloxane moiety, 5‐(3‐trimethoxysilylpropyloxymethyl)‐1,3‐oxathiolane‐2‐thione, was synthesized from the corresponding epoxide precursor by its cycloaddition with carbon disulfide. The siloxane group underwent condensation reaction by the treatment with water and a basic or acidic catalyst, to afford the corresponding oligomer having siloxane main chain and DTC pendant. The resulting oligomer was liquid and soluble in organic solvents such as THF and chloroform. Treatment of the oligomer with amines resulted in selective ring‐opening reaction of the DTC group, generating a thiol group, which underwent oxidative coupling reaction to make the oligomer successfully cured. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4422–4430, 2005 相似文献
142.
143.
Yoshiaki Hamada Kazuko Hashiguchi Masamichi Tsuboi Yoshinori Koga Shigeo Kondo 《Journal of Molecular Spectroscopy》1984,105(1):70-80
Methyleneimine was detected in the gas phase by a moderately high resolution infrared spectrometer as one of the intermediate species produced by a pyrolysis of amines. Observed vibrational frequencies of some isotopic derivatives have been combined with the ab initio values to reach a most reliable force constants set. Some other spectroscopic parameters, involving geometrical parameters and dipole moment derivatives, have also been calculated ab initio and compared with the observation. Its half-life in our experimental apparatus was about 10 min, which is much longer than the previously reported values, 0.1 or 10 sec. 相似文献
144.
145.
146.
We show analytically that application of an identity in conformal invariant field theories to multidimensional guided-wave optics predicts a generic family of modes with algebraic (power-law) tails in the evanescent field. 相似文献
147.
Yoshiaki Amatatsu Yoshiaki Hamada Masamichi Tsuboi Masaaki Sugie 《Journal of Molecular Spectroscopy》1985,111(1):29-41
The infrared spectrum of N-methylvinylamine was observed for the first time in the gas phase by the pyrolysis of propyleneimine. The half-life of this molecule was about 40 sec under our experimental conditions, and the molecule isomerized immediately into its tautomer, N-methylethylideneimine. The absorption bands were assigned by the help of an ab initio MO calculation. 相似文献
148.
An ab initio Mo method was applied to analyse the vibrational spectra of amines and their pyrolytic products. The result was useful to predict the frequencies of group vibrations, and to explain the characteristics of molecular parameters. The relative populations of rotational conformers were calculated and the results were found to be in qualitative agreement with what were observed. 相似文献
149.
Yosuke Ohkura Kenji Ohtsubo Kiyoshi Zaitsu Kazuya Kohashi 《Analytica chimica acta》1978,99(2):317-324
A sensitive fluorimetric method for the determination of aromatic aldehydes is based on their reaction in dilute sulfuric acid with a new reagent, 2,2'-dithiobis(l-amino-naphthalene) in the presence of tri-n-butylphosphine, sodium sulfite and sodium phosphite at ambient temperature. The fluorescences produced are fairly characteristic of individual aldehydes. The method is extremely selective for aromatic aldehydes and very sensitive, especially for p-hydroxybenzaldehyde, o-methoxybenzaldehyde, p-methoxybenzaldehyde and p-tolualdehyde which can be determined at concentrations of as little as 3–5 ng ml-1. 相似文献
150.
Kawasaki I Tsunoda K Tsuji T Yamaguchi T Shibuta H Uchida N Yamashita M Ohta S 《Chemical communications (Cambridge, England)》2005,(16):2134-2136
A novel task-specific ionic ligand with an imidazolium salt moiety was synthesized, and its catalytic ability and recyclability for asymmetric transfer hydrogenation of acetophenone derivatives with a formic acid-triethylamine azeotropic mixture in an ionic liquid [bmim][PF6] was examined. 相似文献