Results 261 to 270 of about 123,857 (304)
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Polycyclic Aromatic Compounds in Nature
Scientific American, 1976A great variety of polycyclic aromatic hydrocarbons (PAHs), including both known and suspected carcinogens, are widespread throughout soils, sea-bottom sediments and petroleum deposits. They are formed whenever organic substances are exposed to high temperatures. The great uniformity of composition and the nature of alkyl substituents suggest that most
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Polycyclic and Heterocyclic Aromatic Compounds
2013This chapter describes the structures of polycyclic aromatic hydrocarbons. It shows that most polycyclic aromatic compounds consist of two or more benzenoid rings fused together but some contain non-benzenoid rings. The chapter also explicates the reactions of polycyclic aromatic compounds, noting some polycyclic aromatic compounds including ...
Tadashi Okuyama, Howard Maskill
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The thermochemistry of some polycyclic compounds
The Journal of Chemical Thermodynamics, 1998Abstract The standard massic energies of combustion of eight polycyclic compounds were measured atT=298.15 K by static-bomb combustion calorimetry. The standard enthalpies of vaporization and sublimation were measured in a Calvet microcalorimeter, or adiabatic vaporization calorimeter, or derived from ebulliometric measurements of the vapour pressure
V.P. Kolesov +4 more
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Aromatic stability of polycyclic compounds
Pure and Applied Chemistry, 1980Abstract
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Polycyclic indole alkaloid-type compounds by MCR
Chem. Commun., 2010Polycyclic indole moieties are often part of bioactive natural or synthetic products, however traditionally have to be synthesized over several steps involving time consuming sequential multi-step syntheses. We herein communicate an efficient and flexible 2-step procedure to complex multicyclic indole alkaloid-type compounds involving Ugi MCR and ...
Wei, Wang +2 more
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Polycyclic aromatic compounds (PAC) in leaf lettuce
Zeitschrift f�r Lebensmittel-Untersuchung und -Forschung, 1986Twenty-three samples of leaf lettuce (Lactuca sativa var. crispa) cultivated in private gardens in southern Finland were analyzed for polycyclic aromatic hydrocarbons (PAH) and derivatives. The total PAH concentrations varied from 4.8 to 94 micrograms/kg fresh weight. Nitro derivatives of PAH were detected in only five samples.
Pyysalo, Heikki +4 more
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Analytical Chemistry, 1986
A previously derived equation for the prediction of chromatographic retention indexes for polycyclic aromatic compounds (PACs) was tested for application to 56 nitro-PACs. A new two-variable equation was derived that applies to a wide range of both PACs and nitrated PACs.
R. H. Rohrbaugh, P. C. Jurs
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A previously derived equation for the prediction of chromatographic retention indexes for polycyclic aromatic compounds (PACs) was tested for application to 56 nitro-PACs. A new two-variable equation was derived that applies to a wide range of both PACs and nitrated PACs.
R. H. Rohrbaugh, P. C. Jurs
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Polycyclic Aromatic Compounds in the Greenland Marine Environment
Polycyclic Aromatic Compounds, 2002Information on levels of polycyclic aromatic compounds (PACs) in the marine environment from pristine areas of the world are still sparse. In this study, PACs were analyzed in sediments and various organisms from the area of Qeqertarsuaq/Disko in the western part of Greenland.
Pécseli, M. +4 more
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Representation of polycyclic aromatic compounds
Journal of Chemical Education, 1958Reviews the representation of polycyclic aromatic compounds and the matter of pi-electron sharing by adjacent sextets.
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Determination of polycyclic aromatic compounds in fish tissue
Journal of Chromatography A, 1988A method is presented for the analysis of polycyclic aromatic hydrocarbons (PAHs), polycyclic aromatic sulfur heterocycles (PASHs), and basic polycyclic aromatic nitrogen heterocycles (PANHs) in fish. The analytical procedure includes Soxhlet extraction of prepared fish tissue with methylene chloride followed by gel permeation chromatography (GPC ...
D A, Birkholz, R T, Coutts, S E, Hrudey
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