Aromatic poly alkane

Diarene metals generally decompose under conditions of normal electrophilic substitution, but dibenzene chromium can be metalated with amyl sodium in alkanes, and subsequent reaction with carbon dioxide and dimethyl sulfate results in a complex mixture of mono-, di-, and poly-substituted dibenzene chromium methyl esters. It is interesting that these polysubstituted compounds are homoannular in contrast to the corresponding ferrocene compounds. In view of the scanty evidence and ease of oxidation, it is impossible to conclude whether the diarene metals are less aromatic than the dicyclopentadienyl metals as predicted by simple theory (Sec. III.A). 

Alkanes and Aromatics. The distinction between aromatic and poly-cyclic was arbitrarily set at three conjugated six-member rings in Table I. With this definition the alkanes and aromatic hydrocarbons, with 25 entries, dominate the list of identified components. These compounds are also present in the highest concentration in the different effluents. Ordinarily their concentrations were not measured because of a low interest in these kinds of compounds but in those instances where measurements were made, the amounts ranged from 10-1500 ng/M3 in the vapor phase and from 10-90 ng/g on the suspended particles in the stack effluents. These hydrocarbons were not quantitated for any of the fly and grate ash samples. 

Small quantities of explosive laboratory chemicals can be destroyed following known methods. By adopting standard methods, it is possible to destroy or reduce the dangerous nature of laboratory chemicals and check their reaction. Hydrocarbons (e.g., alkanes, alkenes, alkynes, arenas) bum well and can be disposed of by incineration or as fuel supplants. Also, many hydrocarbons commonly used in chemical laboratories may be easily ignited. Some cyclic compounds such as alkanes and cyclohexane may form explosive peroxides. Personnel trained in handling explosives should destroy these compounds using detonation. Many poly(nitro) aromatic compounds are explosive, and their disposal requires the services of an expert. 

Many computational studies of the permeation of small gas molecules through polymers have appeared, which were designed to analyze, on an atomic scale, diffusion mechanisms or to calculate the diffusion coefficient and the solubility parameters. Most of these studies have dealt with flexible polymer chains of relatively simple structure such as polyethylene, polypropylene, and poly-(isobutylene) [49,50,51,52,53], There are, however, a few reports on polymers consisting of stiff chains. For example, Mooney and MacElroy [54] studied the diffusion of small molecules in semicrystalline aromatic polymers and Cuthbert et al. [55] have calculated the Henry s law constant for a number of small molecules in polystyrene and studied the effect of box size on the calculated Henry s law constants. Most of these reports are limited to the calculation of solubility coefficients at a single temperature and in the zero-pressure limit. However, there are few reports on the calculation of solubilities at higher pressures, for example the reports by de Pablo et al. [56] on the calculation of solubilities of alkanes in polyethylene, by Abu-Shargh [53] on the calculation of solubility of propene in polypropylene, and by Lim et al. [47] on the sorption of methane and carbon dioxide in amorphous polyetherimide. In the former two cases, the authors have used Gibbs ensemble Monte Carlo method [41,57] to do the calculations, and in the latter case, the authors have used an equation-of-state method to describe the gas phase. 

The "family-plot retention data of 5 solutes with a series of poly(methylphenylsiloxane) stationary phases have been examined in terms of the saturation vapor pressure Pa of the solute, the methyl/phenyl ratio of the solvent, and the temperature. Plots of In Vg against In p for a given solute over a range of temperature were found to De linear, as were the "isothermaV, that is, the retention/vapor -pressure plots for an homologous series of solutes at a constant temperature. The family-plot slopes exhibited by the n-alkane probe-solutes were also found to be very sensitive to the aromatic content of the polymers. Thus, it appears that the "family" technique of GC data reduction can be a useful tool for characterizing the physicochemical properties of (polymer) stationary phases. 

This paper presents data on isolation and identification of the following types of geolipids from the Aleksinac oil shale, a Miocene lake sediment n-al-kanes, iso- and/or anteiso-alkanes, aliphatic iso-prenoid alkanes, polycyclic isoprenoid alkanes, aromatic hydrocarbons, saturated unbranched, aliphatic isoprenoid, hopanoic, and aromatic mono- and poly-carboxylic acids, fatty acid methyl esters, aliphatic y- and 6-lactones, cyclic y-lactones, aliphatic methyl- and isoprenoid ketones, and the triterpenoid ketone adiantone. Possible origin of the identified compound classes is discussed, particularly of those which had not been identified previously as geolipids. 

Crude petroleum contains complex mixtures of hydrocarbons as well as relatively small amounts of nitrogen-, sulfur-, and oxygen-containing organic compounds, asphaltenes, and various trace metals (uncomplexed and complexed forms). The hydrocarbons can be divided into two classes related to their chemical structure the alkanes (normal, branched, and cyclo) and aromatic compounds (mono-, di-, and poly-, i.e., PAH). 

Simple Authors alkanes Congested alkanes C3 Cycloalkanes (size) C4 C5--C7 C8-C12 Poly- cyclics Con- jugated Alkenes Alkynes alkenes Silanes Thianes Halides Ketones Aromatic Acid deriv. 

Organic aerosols formed by gas-phase photochemical reactions of hydrocarbons, ozone, and nitrogen oxides have been identified in both urban and rural atmospheres (Grosjean, 1977). Most of these species are di- or poly-functionally substituted alkane derivatives. These compounds include aliphatic organic nitrates (Grosjean and Friendlander, 1975), di-carboxylic acids (adipic and glutaric acids) (O Brien et al., 1975), carboxylic acids derived from aromatic hydrocarbons (benzoic and phenylacetic acids), polysubstituted phenols, and nitroaromatics from aromatic hydrocarbons (Kawamuraet al., 1985 Satsumakayashi et al., 1989, 1990). Some species that have been identified in ambient aerosol and are be-... 

Another type of azohenzene containing monomers are malonic es-ters. The azo dye. Disperse Red 1, is fixed as the ester functionality. Poly(malonic ester)s are then prepared by the reaction of the active hydrogens in the malonic ester with a, ca-alkanes, or aromatic compounds, such as dibromoxylylenes in presence of sodium hydride. 

Properties Coloriess to It. yel. tinted oil misc. with ketones, esters, aromatics, alkanes, chlorinated alkanes, simple alcohols dens. 15 Ib/gal vise. 8000 cP (20 C) Tg -50 C 100% act. = 31% F Poly-G 20-28 [BASF/Perf. Chems.]... 

White [25] investigated the transport properties of a series of asymmetric poly-imide OSN membranes with normal and branched alkanes, and aromatic compounds. His experimental results were consistent with the solution-diffusion model presented in [35]. Since polyimides are reported to swell by less than 15%, and usually considerably less, in common solvents this simple solution-diffusion model is appropriate. However, the solution-diffusion model assumes a discontinuity in pressure profile at the downstream side of the separating layer. When the separating layer is not a rubbery polymer coated onto a support material, but is a dense top layer formed by phase inversion, as in the polyi-mide membranes reported by White, it is not clear where this discontinuity is located, or whether it wiU actually exist The fact that the model is based on an abstract representation of the membrane that may not correspond well to the physical reality should be borne in mind when using either modelling approach. 

The activity coefficients and interaction parameters w ere also determined for other polymer-solute systems (a) normal, branched and cyclic alkanes and aromatic hydrocarbons in poly (methyl methacrylate) [60,100] ... 

The partial molar quantities of mixing were determined for normal and branched alkanes (O5 — Cio), cyclohexane, benzene and tetrachloromethane in polyisobutylene [57]. Partial molar enthalpies of mixing were measured for normal alkenes in low and high density polyethylene, polypropylene, polybutene-1, polystyrene, poly(methyl acrylate), poly(vinyl chloride), polyCN-isopropyl-acrylamide), ethylene-vinyl acetate copolymer, ethylene-carbon oxide copolymer [88] normal, branched and cyclic alkanes, benzene, n-butylbenzene, ois- and ra s-decalin, tetraline and naphthalene in polystyrene at 183, 193 and 203°C [60] these solutes in poly (methyl acrylate) [57] n-nonane, n-dodecane and benzene in polystyrene in the range 104.8 — 165.1 C [71] O7—C, C12 normal alkanes and aromatic hydrocarbons in polystyrene at an average temperature of 204.9°C [72], C7—Cg normal alkanes in poly(ethylene oxide) at an average temperature of 66.5 "C [72] normal alkanes in ethylene oxide—propylene oxide block copolymers (Pluronics L 72, L 64 and F 68) at the same average temperature [72]. 

The global solubility parameters of polymers were determined from partial molar enthalpies of mixing [60, 71, 72], from partial molar free energies of mixing [60] and from the polymer-solute interactions parameters [60, 68, 101, 108, 109] all these functions were obtained by GLC. For normal, branched and cyclic alkanes, aromatic hydrocarbons and tetraline in polystyrene, eqns (5.40) and (5.42) yield Sj = 7.6 0.2 and 82 = 7.4 i 0.4 cali/2 "cm /z [60] at an average column temperature of 193°C. The same substances in poly(methyl acrylate) give 82 = 8.7 0.3... 

SWCNTs-porphyrin nanosensors have been fabricated for monitoring toxic substances in the enviromnent [215], Free-base, Ru and Fe octaethyl-and tetraphenyl-substituted porphyrins provided good selectivity and sensitivity to various VOCs tested (acetone, butanone, methanol, ethanol). Nonco-valently functionalized SWCNTs with iron tetraphenylporphyrin were used for benzene detection [216], SWCNTs noncovalently functionalized with copper phthalocyanine and free-base porphyrins were used as sensing layers for the detection of toluene [217]. Also, MWCNTs were used as sensors for benzene, toluene, and xylene, when fnnctionalized with metal tetraphenyl porphyrins [218], SWCNTs-poly(tetraphenylporphyrin) hybrid was prepared and tested as a low-power chemiresistor sensor for acetone vapor [219]. A chemiresistive sensor array was fabricated from SWCNTs noncovalently functionalized with metallo mcxo-tetraphenylporphyrins (Cr(III), Mn(III), Fe(III), Co(III), Co(n), Ni(n), Cu(II), and Zn(II)) [220]. Its responses were treated by statistical analyses and allowed to classify VOCs into five classes alkanes, aromatics, ketones, alcohols, amines. Amines detection as an indicator of meat spoilage was achieved by the same group with the same sensor array [221]. 

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