Hydrocarbons causing

Acyl chlorides, Aromatic hydrocarbons EfFenberger, F. et al., Angew. Chem. (Intern. Ed.), 1972, 11, 300 Addition of catalytic amounts (1%) of the acid (stronger even than perchloric acid) to mixtures of acyl chlorides and aromatic hydrocarbons causes more or less violent evolution of hydrogen chloride, depending on the reactivity of the Friedel-Crafts components. 

Rotenberg SA, Weinstein IB. 1991. Two polychlorinated hydrocarbons cause phospholipid-dependent protein kinase C activation in vitro in the absence of calcium. Molecular Carcinogenesis 4 477-481. 

Most fluorescent PET molecular sensors, including pH indicators of this type, consist of a fluorophore linked to an amine moiety via a methylene spacer. Photo-induced electron transfer (see Chapter 4, Section 4.3), which takes place from amino groups to aromatic hydrocarbons, causes fluorescence quenching of the latter. When the amino group is protonated (or strongly interacts with a cation), electron transfer is hindered and a very large enhancement of fluorescence is observed. 

Halothane and all other halogenated hydrocarbons cause some relaxation of skeletal muscle. The relaxation is not adequate when muscle paralysis is a requirement of the operative procedure, but halothane s action will... 

Irreversible electrochemical oxidation of dimeric 4//-pyrans 163 to monomeric pyrylium ions at about +0.6 V was observed.225,227,228 The anodic oxidation of the dimers in the presence of aromatic hydrocarbons caused electroluminiscence of the latter.228,472 The polarographic oxidation of carbo-ranyl 4//-pyran 174a (R = Ph) at a platinum microelectrode was found to... 

The denitration system works satisfactorily only for spent acid from the nitration of glycerine and similar alcohols. In spent acid from trinitrotoluene production the high content of dissolved nitrated hydrocarbons causes an excessive reduction of nitric arid at the top of the denitrating tower. Thus spent acid from the nitration... 

The liquid hydrocarbon causes separation of the asphaltenes and/or the resins from the feedstock leaving a deasphalted oil that contains substantially less sulfur and metals than the feedstock. On a commercial scale, propane is the most common solvent (Figure 7-21) and the units are designed to operate at 40 to 80°C (105 to 175°F) and at pressures of 400 to 550 psi with the solvent/ feedstock ratio usually falling in the range 5 1 to 13 1. 

Probably the same reaction, the dehydrogenation, condensation, and irreversible adsorption of highly condensed aromatic hydrocarbons, causes the loss of activity of the WS2 catalyst when used at pressures well below 200 atm. As an example (20), in experiments with a paraffin-base petroleum-oil fraction boiling between 200° and 325°C. the results in the accompanying tabulation were obtained ... 

A number of environmental contaminants (e.g., some organo-chlorine pesticides, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons) cause cancer in laboratory animals. The committee found no epidemiological evidence to suggest that these compounds individually make a major contribution to the risk of cancer in humans. However, the possibility that they may act synergistically and may thereby create a greater carcinogenic risk cannot be excluded. 

Refrigerants and aerosol propellants have been gases of abuse. Inhalation of high-concentration halogenated hydrocarbons causes euphoric effects and later... 

Figure 11,13 During contact between a reduced catalyst and hydrocarbons, it i,s possible to obscr e the formation of Pt ( bonds. Stopping the flow of hydrocarbons causes the gradual disappearance of bonds (taken from N, Somoijai Guyot-Sionnest. Structural evolution of Pt-Al203 catalysts during reduction and hydrocarbon reaction a high temperature, high pressure EXAFS study. These, Universitc Paris-Sud, 1991).

Grover, P. How polycyclic hydrocarbons cause cancer. New Scientist. 55, 685 (1973). 

Mixtures of formaldehyde with other VOCs, including aliphatic and aromatic hydrocarbons, cause unexpected illnesses even at low level exposures. 14 ... 

Toxicity. Mineral oils produce slight-to-moderate irritation by standard rabbit skin irritation tests (Beck et al., 1982 Mayhew et al., 1985). Repeated applications of mineral oils to skin over a week resulted in epidermal hyperplasia, hyperkeratosis, and depilation C14-C19 hydrocarbons caused more damage than C21-C23 hydrocarbons (Hoekstra and Phillips, 1963). 

The CMC of the surfactant in the aqueous phase is changed very little by the presence of a second liquid phase in which the surfactant does not dissolve appreciably and which, in turn, either does not dissolve appreciably in the aqueous phase or is solubilized only in the inner core of the micelles (e.g., saturated aliphatic hydrocarbons). When the hydrocarbon is a short-chain unsaturated, or aromatic hydrocarbon, however, the value of the CMC is significantly less than that in air, with the more polar hydrocarbon causing a larger decrease (Rehfeld, 1967 Vijayendran, 1979 Murphy, 1988). This is presumably because some of this second liquid phase adsorbs in the outer portion of the surfactant micelle and acts as a class I material (Section C). On the other hand, the more polar ethyl acetate increases the CMC of sodium dodecyl sulfate slightly, presumably either because it has appreciable solubility in water and thus increases its solubility parameter, with consequent increase in the CMC of the surfactant, or because the surfactant has appreciable solubility in the ethyl acetate phase, thus decreasing its concentration in the aqueous phase with consequent increase in the CMC. 

Effect of Monomeric Organic Additives The presence of solubilized hydrocarbon in the surfactant micelles generally increases the solubility of polar compounds in these micelles. The solubilized hydrocarbon causes the micelle to swell, and this may make it possible for the micelle to incorporate more polar material in the palisade layer. On the other hand, the solubilization of such... 

Impurities in the gas (oil, water, oxygen, hydrocarbons) cause baseline problems. 

Aliphatic hydrocarbons such as iso-octane could be reformed without significant carbon formation even when equilibrium predicted carbon formation. However, the addition of aromatic hydrocarbons caused significant carbon formation. The addition of anti-oxidants to the fuel stream did not make any measurable difference in carbon formation. 

Human cell response to environmental organic toxins. Holman et al. (2000) have investigated the changes in intracellular phosphate and lipid concentrations in human cells as a function of exposure to polychlorinated hydrocarbons and compared their findings to quantitative results from reverse transcription polymerase chain reaction (RT-PCR). The human cells were exposed to low doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent and well-studied man-made toxin. TCDD causes harmful effects at exposure levels of hundreds to thousands of times lower doses than most chemicals of environmental concern. This polychlorinated hydrocarbon causes an increase in the production of the cytochrome P4501A1 (CYP1A1) gene, which can be monitored with RT-PCR. 

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