/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://dx.doi.org/10.1021/ef8002526 Energy & Fuels, 22, 5, pp. 3390-3394, 2008-09-01 Ionic pairs in PPA-modified bitumen: insights from model compounds Masson, J-F.; Gagné, M.http://irc.nrc-cnrc.gc.ca Ionic pairs in polyphosphoric acid (PPA)-modified bitumen: insights from model compounds NRCC-50428Masson, J-F. ; Gagné, M.A version of this document is published in / Une version de ce document se trouve dans: Energy & Fuels, v. 22, no. 5, Sept. 2008, pp.3390-3394, Doi: 10.1021 The material in this document is covered by the provisions of the Copyright Act, by Canadian laws, policies, regulations and international agreements. Such provisions serve to identify the information source and, in specific instances, to prohibit reproduction of materials without written permission. AbstractThe reaction between polyphosphoric acid (PPA) and bitumen is ill understood. To help define possible reactions, model compounds, isoquinoline and 1-methyl-2-quinolinone, were reacted with PPA. Both compounds formed salts with PPA. An infrared study of the salts revealed that PPA releases a terminal proton, as opposed to an internal one, and that with isoquinoline, the charges of the ionic pair are localized, but stabilized by bound water. With 1-methyl-2-quinolinone, the charges are delocalized and stabilized by resonance. This study demonstrates that ionic pairs need an environment of high dielectric constant to form in bitumen.

Relatively little is known about the effect of polyphosphoric acid (PPA) on bitumen chemistry and structure. In an effort to increase this understanding, the reaction of indole with PPA was studied by Fourier-transform infrared spectroscopy (FTIR). Indole contains a pyrrole functional group very common in bitumen. The results revealed that both the amine and the double bond of indole can be reactive, and that indole concentration affected the reaction pathway. All reactions began with the protonation of the indole double bond, which provided two reactive carbocation intermediates. When the concentration of indole was high, each carbocation coupled with unprotonated indole and two products were obtained. In one case two N-H groups produced a N-N bond, and in the other case two indole double bonds to produced a cyclobutane ring. When the concentration of indole was reduced by dilution, N-H coupling proceeded without double bonds coupling, and a reaction with the PPA anion was found to occur instead. These findings indicate that the effect of PPA in bitumen may be to raise molecular stiffness through N-N bridging, while at the same time disrupt the hydrogen bond network where the N-H function of pyrrole groups is involved and reduce the effective molecular weight of asphaltenes.

/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://dx.doi.org/10.1021/ef800511v Energy & Fuels, 22, 6, pp. 4151-4157, 2008-10-15 Reactions of polyphosphoric acid and bitumen model compounds with oxygenated functional groups : Where is the phosphorylation? Masson, J-F.; Gagné, M.; Robertson, G.; Collins, P.http://irc.nrc-cnrc.gc.caReactions of polyphosphoric acid and bitumen model compounds with oxygenated functional groups : where is the phosphorylation NRCC-50561Masson, J-F.; Gagné, M.; Robertson, G.; Collins, P. 2008-10-15A version of this document is published in / Une version de ce document se trouve dans: Energy Fuels, v. 22, no. 6, 2008, pp. 4151-4157 The material in this document is covered by the provisions of the Copyright Act, by Canadian laws, policies, regulations and international agreements. Such provisions serve to identify the information source and, in specific instances, to prohibit reproduction of materials without written permission. In an effort to better understand these reactions, and phosphorylation in particular, four bitumen model compounds with various oxygenated functional groups were heated with PPA in conditions typical of those used to prepare PPA-modified bitumens, namely, bisphenol A (phenol), butyl phenyl ether (ether), acetophenone (ketone) and benzoic acid (carboxylic acid). The reactions were followed by thin-layer chromatography and infrared spectroscopy. It was found that the extent of the reactions decreased as bisphenol A > acetophenone > benzoic acid > butyl phenyl ether. The detailed analysis of the infrared spectra revealed that the hydroxyl group of bisphenol A was not phosphorylated by PPA. Instead, it facilitated the scission of the bisphenol into fragments of lower molecular weight. The reaction of acetophenone had the reverse effect, as it led to condensation. Benzoic acid and butyl phenyl ether were immune to the effect of PPA when heated alone with PPA, but heated together they condensed into higher molecular weight aryl-aryl ketones and esters. These findings are consistent with changes known to occur in PPA-modified bitumen. For instance, the breaking down of bisphenol may relate to the decrease in the molecular weight of asphaltenes, whereas the intermolecular reactions translates into an extension of the bitumen molecular backbone that helps explain bitumen stiffening. The key ...

Experience with the use of formal descriptions of communication services and protocols is described. The paper focuses on the experience of the authors with the extended state transition model which is proposed as a standard formal description technique (FDT) for the services and protocols in the OS1 environment. The first part of the paper refers to various example specifications, including transport protocol and service specifications, and discusses the suitability of the specification method and possible extensions.In the remaining part, the use of such formal specifications during the phases of system design, implementation, and testing is described. Various approaches to protocol design validation, implementation, and assessment of implementations are discussed, with emphasis on the last point.The experience with several of these approaches is described in the paper, and further details may be found in the references.