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Interpretation of hydrocarbon

As described in the Introductory Chapter, attention was focused [1] prior to 1961 mainly on the morphology of the cool-flame and ignition regions, rates were followed by pressure change, and essentially chemical techniques were used for product analysis. The acceptance of free radicals, followed by the masterly and elegant Semenov theory [2], which established the principles of branched chain reactions, provided the foundation for modern interpretations of hydrocarbon oxidation. This chapter builds on these early ideas, and pioneering experiments such as those carried out by Knox and Wells [3] and Zeelenberg and Bickel [4], to provide a detailed account of the reactions, thermochemistry and detailed mechanisms involved in the gas-phase chemistry of hydrocarbon oxidation. [Pg.1]

Harding, T.P. and Tuminas, A.C. 1989. Structural interpretation of hydrocarbon traps sealed by basement normal blocks and at stable flank of foredeep basins and at rift basins. Am. Assoc. Pet. Geol. Bull., 73 812-840. [Pg.37]

Interpretation of Hydrocarbon Analyses. Although obtaining accurate hydrocarbon measurements in samples is often a difficult task, it is equally as difficult to determine the sources of hydrocarbons from the data. The following criteria for differentiating petroleum hydrocarbons from biogenic hydrocarbons that have been suggested and applied over the past several years were outlined in (1) and are taken from there. [Pg.16]

The most common interfering substance, especially with alcohols of low mole cular weight, is water this may result in an inaccurate interpretation of the test if applied alone. Most of the water may usually be removed by shaking with a little anhydrous calcium sulphate,. though dry ethers (and also the saturated aliphatic and the simple aromatic hydrocarbons) do not react with sodium, many other classes of organic compounds do. Thus ... [Pg.1066]

Rates that are independent of aromatic substrate concentration have been found for reaction of benzyl chloride catalyzed by TiCl4 or SbFj in nitromethane. This can be interpreted as resulting from rate-determining formation of the electrophile, presumably a benzyl cation. The reaction of benzyl chloride and toluene shows a second-order dependence on titanium tetrachloride concentration under conditions where there is a large excess of hydrocarbon. ... [Pg.581]

To select the proper heat transfer relations to represent the functions, you need to analyze the heat transfer functions that will take place in the unit-tube and/or on the shell side. Some units may have several functions, such as the example in Rubin s recommendations on this subject that is, steam desuperheating and hydrocarbon condensing steam and hydrocarbon condensing, and condensate subcooling. Rubin presents an excellent interpretation of multizone operation for several different sets of conditions. See Figures 10-91Aand 10-91B. [Pg.154]

A simplification in the graphical interpretation of acyclic chemical compounds is possible in the case of saturated acyclic hydrocarbons, once known as paraffins but now more usually called "alkanes". These have the general formula indicating the... [Pg.105]

On the other hand, the formation of ethylene was ascribed mainly to the unimolecular decomposition of a neutral excited propane molecule. These interpretations were later confirmed (4) by examining the effect of an applied electrical field on the neutral products in the radiolysis of propane. The yields of those products which were originally ascribed to ion-molecule reactions remained unchanged when the field strength was increased in the saturation current region while the yields of hydrocarbon products, which were ascribed to the decomposition of neutral excited propane molecules, increased several fold because of increased excitation by electron impact. In various recent radiolysis 14,17,18,34) and photoionization studies 26) of hydrocarbons, the origins of products from ion-molecule reactions or neutral excited molecule decompositions have been determined using the applied field technique. However, because of recent advances in vacuum ultraviolet photolysis and ion-molecule reaction kinetics, the technique used in the above studies has become somewhat superfluous. [Pg.272]

Low energy ion-molecule reactions have been studied in flames at temperatures between 1000° and 4000 °K. and pressures of 1 to 760 torr. Reactions of ions derived from hydrocarbons have been most widely investigated, and mechanisms developed account for most of the ions observed mass spectrometrically. Rate constants of many of the reactions can be determined. Emphasis is on the use of flames as media in which reaction rate coefficients can be measured. Flames provide environments in which reactions of such species as metallic and halide additive ions may also be studied many interpretations of these studies, however, are at present speculative. Brief indications of the production, recombination, and diffusion of ions in flames are also provided. [Pg.297]

Recently, a nonempirical rr-electron SCF approach was reported and applied to interpretations of spectra of various conjugated hydrocarbon radicals (147). The greatest attention, however, has been paid to radical ions derived from even alternant hydrocarbons (10, 58-60, 63, 125, 135, 148-153). Here, numerous experimental material suitable for systematic testing of the MO methods has been accumulated. In particular, the following sources of experimental data should be mentioned Hamill and collaborators (24) prepared... [Pg.359]

Simon, D.M., Belles, F.E., and Spakowski, A.E., Investigation and interpretation of the flammability region for some lean hydrocarbon-air mixtures, Proc. Comb. Inst., 4 126,1953. [Pg.109]

The interpretation of the IR data and subsequent X-ray photoelectron spectroscopy studies in UHV conditions indicate that at room temperature CO is adsorbed on the Co surface. Under higher temperatures, H starts to occupy some available sites, and hydrocarbons form at the defect sites. Finally, at room temperature and under vacuum conditions the hydrogen desorbs from the Co, while the Co and hydrocarbons remain. [Pg.45]

MO) with the protons in the nodal plane. The mechanism of coupling (discussed below) requires contact between the unpaired electron and the proton, an apparent impossibility for n electrons that have a nodal plane at the position of an attached proton. A third, pleasant, surprise was the ratio of the magnitudes of the two couplings, 5.01 G/1.79 G = 2.80. This ratio is remarkably close to the ratio of spin densities at the a and (3 positions, 2.62, predicted by simple Hiickel MO theory for an electron placed in the lowest unoccupied MO (LUMO) of naphthalene (see Table 2.1). This result led to Hiickel MO theory being used extensively in the semi-quantitative interpretation of ESR spectra of aromatic hydrocarbon anion and cation radicals. [Pg.24]

Bartell and coworkers investigated the structures of a series of noncyclic alkanes by means of gas electron diffraction (14, 44, 45) and invoked for the interpretation of their results a simple force field which contained to a high extent vibrational spectroscopic constants of Snyder and Schachtschneider. This force field reproduces bond lengths and bond angles of acyclic hydrocarbons well, energies of isomerisation satisfactorily. As an example, Fig. 8 shows geometry parameters of tri-t-butylmethane as observed by electron diffraction and calculated with this force field (14). [Pg.187]

Ion-molecule reactions involve a positive ion and a neutral molecule, frequently the parent molecule. Historically, there has been a dichotomy in the interpretation of the radiation-chemical yields in hydrocarbon gases. Early work by Lind (1961) and by Mund (1956) indicated the involvement of ion clustering, exemplified in the radiation-induced polymerization of acetylene as follows ... [Pg.122]

In the last two decades, there has been a large accumulation of experimental evidence as well as of theoretical interpretations of intramolecular reactions. One notes, however, that attention has been focused on the phenomena of immediate interest to the various specialists. As a consequence of the fact that specialisation implies intensification of knowledge on the one hand but limitation on the other, there has still been insufficient communication and cross-fertilisation between the different schools. This situation is well exemplified by the two most extensive reviews on intramolecular phenomena, namely, that of Kirby (1980), entitled Effective Molarities for Intramolecular Reactions , and that of Winnik (1981a), entitled Cyclisation and the Conformation of Hydrocarbon Chains , which present different approaches and apparently unrelated facts and theories. [Pg.3]

It seems that these essential differences between alkenes and vinyl ethers were ignored when the kinetic interpretation of the polymerizations of alkenes by ionizing radiations were extended to the vinyl ethers, but any or all of them may help us to understand the behavioural differences between hydrocarbons and hetero-atomic monomers (see Section 4c). [Pg.348]


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