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921.
I. B. Rabinovich N. V. Karyakin É. S. Dzharimova S. A. Siling I. I. Ponomarev S. V. Vinogradova 《Russian Chemical Bulletin》1984,33(4):716-723
Conclusions The reaction of phthalonitrile condensation with m-phenylenediamine is thermodynamically allowed at temperatures from 250° to 500°K, and its equilibrium is almost completely shifted toward the formation of the macroheterocycle.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 779–787, April, 1984. 相似文献
922.
923.
We present a general method of determining the structure and charge of globular ionic micelles, using neutron small-angle scattering. The micellar solutions may have any concentration within the micellar phase. The method is based in part on an analytic calculation of the interparticle correlations between monodisperse spherical micelles, and we discuss the theory in some detail to justify its application to polydisperse globular particles. Experimental results are presented for several cationic and anionic micellar systems. 相似文献
924.
B. N. Achar G. M. Fohlen J. A. Parker 《Journal of polymer science. Part A, Polymer chemistry》1983,21(1):111-120
The reactions of 4-aminophthalonitrile (APN) with 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BPTDA), and with 1,2,3,4-benzenetetracarboxylic dianhydride (PMDA) have been studied to optimize the conditions for the synthesis of monomeric thermosetting bisphthalonitrile compound. Suitable procedures for the synthesis of the two monomers are presented. Elemental analyses, IR spectra, dynamic thermogravimetric analyses, differential scanning calorimetry, 1H-NMR, and mass spectral studies have been used to characterize these compounds. Preliminary observations show that these materials can be polymerized to give high-temperature-resistant materials. 相似文献
925.
926.
N. V. Abbakumova A. F. Vasil'ev E. B. Nazarova 《Chemistry of Heterocyclic Compounds》1981,17(7):719-722
On the basis of a study of the vibrational spectra in the solid state of the product of the reaction of 2-cyanophenyl isocyanate with hydroxylamine and its isotopic analogs (15N O and 15NH2) it was demonstrated that the compound obtained has the 4-amino-1H-quinazolin-2-one 3-oxide structure.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 968–972, July, 1981. 相似文献
927.
B. B. Idage S. P. Vernekar N. D. Ghatge 《Journal of polymer science. Part A, Polymer chemistry》1983,21(2):385-395
Azo compounds such as di(4-hydroxybutyl)-2,2′-azobisisobutyrate, di(3-hydroxybutyl)-2,2′-azobisisobutyrate, di(2-hydroxypropyl)-2,2′-azobisisobutyrate, and di(2-hydroxyethyl)-2,2′-azobisisobutyrate were prepared and used as initiators for the preparation of hydroxyl-terminated polybutadienes (HTPBs) of molecular weight (M?n) ranging from 2000 to 7500 and functionality between 1.90 and 3.0. The polymers were prepared by free-radical solution polymerization in dioxane and toluene. The polymers obtained were characterized for their molecular weight, hydroxyl number, functionality, and instrinsic viscosity. 相似文献
928.
929.
930.
A calcium phosphate apatite which contains some different nitrogen oxides is studied by the ESR technique. NO2?2 ions are evidenced and characterized. They stay in the apatite channels with their OO direction along the channel axis. ESR experiments at different temperatures show that these ions rotate around this axis when the temperature becomes higher than that of liquid nitrogen. 相似文献