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91.
Yan-Feng Wang Tian-Ming Chen Yu-Jun Li Masaya Kitamura Ikuko Sakurai Tadao Nakaya 《Journal of polymer science. Part A, Polymer chemistry》1997,35(14):3065-3074
Polyamides (4a-b and 5a-b) were synthesized from interfacial polycondensation of novel diamine containing phosphatidylcholine analogous moiety, hexamethylene diamine with adipoyl chloride, or sebacoyl chloride in the interface of water and carbon tetrachloride at room temperature. The characterizations of synthesized diamine and polyamides were carried out with FT-NMR, or IR spectral method, elemental analysis, and melting point measurements, respectively. These polyamides obtained are insoluble in any normal solvents. From the results of X-ray diffraction analysis and POM observation, it was revealed that the polyamide 4b was prepared with high molecular weight, while polyamide 4a obtained seemed to have low molecular weight. For copolymers 5a and 5b, X-ray reflections from only adipoyl or sebacoyl chloride parts were observed as in crystalline state. In addition, thermal properties were also studied by DSC and transmitted light intensity measurements. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 3065–3074, 1997 相似文献
92.
Yu-Jun Li Naotoshi Nakamura Tian-Ming Chen Yan-Feng Wang Masaya Kitamura Tadao Nakaya 《Macromolecular rapid communications》1996,17(10):737-744
Three new amphiphilic phospholipid diols containing hydrophilic phosphatidylcholine analogues in the main chains and hydrophobic octadecyl, hexadecyl or dodecyl alkyl groups in the side chains were synthesized. The typical phospholipid diol based on an octadecyl group was further reacted with diisocyanates such as hexamethylene diisocyanate (HDI), 2,4-tolylene diisocyanate (TDI) and 4,4′-methylenediphenyl diisocyanate (MDI), respectively. Preliminary studies suggest that polyurethane based on MDI shows a viscosity behavior similar to common polyelectrolytes and exhibits a therm decomposition peak at 244°C due to the phospholipid moiety and a melting point at 218°C. 相似文献
93.
Several new polyurethanes containing cholesterol and phosphatidylcholine analogous moieties were synthesized by addition polymerization of 2-[bis(2-hydroxyethyl)methylammonio]ethyl 5-cholesten-3β-yl phosphate ( 2 ) with diisocyanates such as hexamethylene diisocyanate (HDI), 2,4-tolylene diisocyanate (TDI), 4,4′-methylenediphenyl diisocyanate (MDI) and m-xylylene diisocyanate (XDI), respectively. They were characterized by their IR and 1H NMR spectral data and elemental analyses. Preliminary studies suggest that these polyurethanes show the viscosity behavior of common polyelectrolytes. 相似文献
94.
95.
Y.-F. Wang T.-M. Chen K. Okada M. Uekawa T. Nakaya M. Kitamura H. Inoue 《Journal of polymer science. Part A, Polymer chemistry》2000,38(11):2032-2040
Two polyimides, PI(C1-BA) and PI(C1-6FDA), based on an aromatic diamine compound and two aromatic dianhydrides [biphenyltetracarboxylic dianhydride (BA) and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA)] were newly synthesized. They were characterized by viscosity, Fourier transform infrared measurements, and X-ray analyses. X-ray results revealed that the crystallinity of PI(C1-BA) was lower than that of PI(C1-6FDA). The synthesized polyimides could be formed into stable and homogeneous thin films on an ITO (indium tin oxide) electrode, functioning as good hole-transport materials for organic electroluminescent (EL) devices. The double-layered EL devices, consisting of the hole-transport layer of these polyimides and an emitting layer of tris(8-quinolinolato)aluminum complex, exhibited a peak emission wavelength in the bright green at 524–527 nm. Moreover, a maximum luminance of 355 cd/m2 was achieved at a voltage of 13 V, with a current density of 600 mA/cm2 for the EL device using PI(C1-BA) as a hole-transport layer. The phenomenon of an extended luminance of these EL devices was also found when the voltage was applied higher than 13 V. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2032–2040, 2000 相似文献
96.
Kenji Sasaki Abu Shara S. Rouf Takashi Hirota Naoki Nakaya 《Journal of heterocyclic chemistry》1999,36(2):461-465
Some novel 5-hydroxyalkylamino-1,2-dihydrothieno[2,3-h][1,6]naphthyridines were prepared by the reaction of 5-chloro-1,2-dihydrothieno[2,3-h][1,6]naphthyridine derivatives with some aminoalcohols in the presence of base. These derivatives were cyclized to the corresponding imidazo or pyrimido derivatives. The bronchodilatory activity of these compounds was evaluated on the basis of their relaxation activity to tracheal contraction induced by carbamylcholine chloride as a primary in vitro assays. Effect of some naphthyridines on carbamylcholine chloride-induced contractions of trachea in the presence or absence of milrinone or 4-(3-butoxy-4-methoxyphenyl)imidazolidin-2-one, which is inhibitor of phosphodiesterase III or IV, were also evaluated. 相似文献
97.
Ibrahim Iliya Zulfiqar Ali Toshiyuki Tanaka Munekazu Iinuma Miyuki Furusawa Ken‐ichi Nakaya Jin Murata Dedy Darnaedi 《Helvetica chimica acta》2002,85(8):2538-2546
Four new stilbene oligomers, gnemonols G, H, I, and J ( 1 – 4 ), were isolated from acetone extract of the root of Gnetum gnemon along with five known stilbenoids, ampelopsin E, cis‐ampelopsin E, gnetins C, D, and E. The structures were elucidated on the basis of spectroscopic evidence. 相似文献
98.
99.
Nakaya R Yasuda S Yorimitsu H Oshima K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(31):8559-8561
100.
Shinji Nakaya Koichi Omi Toshiki Okamoto Yutaka Ikeda Che Zhao Mitsuhiro Tsue Hideyuki Taguchi 《Proceedings of the Combustion Institute》2021,38(4):5933-5942
Combustion instabilities were investigated experimentally for a hydrogen-rich combustion in a model afterburner installed at the end of a high-enthalpy wind tunnel. Air was supplied at 0.3 MPa and 950 K. The combustion instabilities were studied with the time-resolved measurements of a near-infrared (NIR) emission from water molecules over 780 nm using a high-speed video camera. Pressure was also measured in the combustor. The pressure and the NIR images were analyzed by data-driven approach, which include the fast Fourier transform (FFT), the wavelet transform, the dynamic mode decomposition (DMD) and the Gaussian process latent variable methods (GP-LVM). Thermoacoustic instability was observed under a rich condition, and the amplitude of the pressure oscillation was the maximum at the overall equivalence ratio of approximately 2.4 or 2.7 as a result of the FFT. The combustion dynamics were investigated in detail for an experimental run at the equivalence ratio of 2.4. A pressure spectrogram indicated a flame–vortex interaction with a Strouhal number of 0.5 (2300 Hz), thermoacoustic instability (560 Hz), and their transitions with the wavelet transform. For NIR images, the same tendency was also observed in the spectrogram of the modes obtained by the Gabor-filtered DMD, which could clearly resolve the high-order harmonic modes of the flame–vortex interaction and the thermoacoustic instability. Furthermore, NIR images were analyzed with GP-LVM to study the evolution of the combustion dynamics in a three-dimensional latent space. Recurrence plots with the Euclidean distance function were used to visualize the evolutions of the combustion dynamics. A limit cycle behavior of the flame–vortex interaction was clearly observed, whereas the limit cycle of the thermoacoustic instability showed more complicated behaviors. The transition behaviors of the instabilities were observed in the recurrence plots in detail, indicating that the flame–vortex interaction excited the fourth harmonic mode of the thermoacoustic instability, followed by the basic mode. 相似文献