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121.
Abdiaziz A. Farah William J. Pietro 《Journal of polymer science. Part A, Polymer chemistry》2005,43(23):6057-6072
A series of poly(N‐(ω′‐alkylcarbazoly) methacrylates) tris(bipyridine) Ru‐centered bifunctional polymers with good filming, thermal, and solubility properties were synthesized and characterized. Atom transfer radical polymerization (ATRP) of N‐(ω′‐alkylcarbazoly) methacrylates in solution was used, where Ru complexes with one and three initiating sites acted as metalloinitiators with NiBr2(PPh3)2 as a catalyst. ATRP reaction conditions with respect to polymer molecular weights and polydispersity indices (PDI) of the target bifunctional polymers were examined. Electronic absorption and emission spectra of the resultant functional polymers provided evidence of chromophore presence within a single polymeric chain. The thermal properties of all polymers were also investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), and these analyses have indicated that these polymers possess higher thermal stabilities than poly(methyl methacrylate) (PMMA) obtained via free radical polymerization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6057–6072, 2005 相似文献
122.
Pietro De Poi 《Mathematische Nachrichten》2005,278(4):363-378
In this article we study congruences of lines in ?n, and in particular of order one. After giving general results, we obtain a complete classification in the case of ?4 in which the fundamental surface F is in fact a variety, i.e. it is integral, and the congruence is the irreducible set of the trisecant lines of F. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
123.
124.
Pietro Cremaschi 《Chemical physics letters》1984,106(4):286-291
Cross sections of the sequential two-photon ionization of Li2 are evaluated starting from ab initio CI wavefunctions and using different laser wavelengths for the excitation and ionization processes. In agreement with experimental results and previous calculations, a substantial isotope separation is found for the three isotopes of Li2, and a wide spectrum of wavelengths useful for effective isotope enrichment is suggested. Even in with an overcrowded spectrum, the fundamental role of Franck-Condon factors and thermal populations in defining the characteristic resonances of the fractionation process is confirmed. This result suggests a practical way to predict transitions useful for isotope enrichment. 相似文献
125.
126.
Reaction of open-chain and cyclic sym-1,3-diones with N,N-dimethylformamide dimethyl acetal gave, generally in high yield, a series of sym-2-dimethylaminomethylene-1,3-diones which reacted with phenylhydrazine and methylhydrazine to afford, generally in satisfactory yield, a number of 1,5-disubstituted 4-acylpyrazoles. The applications and limits of this new pyrazole synthesis are presented and discussed. 相似文献
127.
Pietro Maravigna 《Journal of polymer science. Part A, Polymer chemistry》1988,26(9):2475-2485
Polycondensation of bisphenol A, hydroquinone, or dihydroxynaphthalenes with glyoxal using methane sulphonic acid as condensing agent leads to polymeric materials having linear and ladder structure and high thermal stability. These polymers were characterized by NMR and TG. Oligomers (from dimer to tetramer) were isolated by GPC and their structures characterized. 相似文献
128.
Pietro Aiena 《Archiv der Mathematik》1988,50(5):459-462
This work was supported in part by the Italian Research Science Foundation (C.N.R.), Fondi Ministeriali 40%, 1986. 相似文献
129.
Robert F. Hout William J. Pietro Warren J. Hehre 《Journal of computational chemistry》1983,4(2):276-282
A scheme is presented that enables photographic representation of the (two-dimensional) surfaces of (three-dimensional) molecular orbitals and electron density functions. The algorithm has been implemented by a program which is completely general and computationally efficient. 相似文献
130.
The potential surfaces of pyrazine, 4-nitropyridine, 1,2-, 1,3-, 1,4- dicyanobenzene radical anions have been calculated within theab initio and electrostatic molecular potential formalism, including the effect of the solvent. These potential surfaces suggest models of ion pairs with alkali cations, which are in agreement with those deduced from related ESR spectra. 相似文献