Download or read book Impact of Halogenated Aliphatic and Aromatic Additives on Soot and Polycyclic Aromatic Hydrocarbons written by Rajiv Kondaveeti and published by . This book was released on 2012 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study is to investigate the effects of aliphatic and aromatic halogenated additives on soot and PAH formation (polycyclic aromatic hydrocarbon) using a laminar co-flow ethylene-air diffusion flame. Both aliphatic surrogates (bromobutane, chlorobutane and bromo/chlorobutane mix) and aromatic surrogates (benzene, bromobenzene, chlorobenzene and bromo/chlorobenzene mix) were added to the base fuel for investigation. The soot particles were collected on quartz filters and their mass was determined using a Leco carbon burn-off method. The gaseous effluents were collected in an Amberlite XAD-2 sorbent trap and extracted using the Soxhlet technique. Gas chromatography / mass spectrometry (GC/MS) was used to identify and quantify the extracted gaseous effluents. Significant amounts of enols were detected along with PAHs, indicating that enols are also important intermediate species in hydrocarbon combustion. The results showed that all the halogenated additives reduced the temperature of the sampling system, indicating flame suppression properties. All the additives gave increased soot yields when compared to the baseline experiment. The brominated fuel additives displayed a higher propensity to soot than the corresponding chlorinated fuel additives. The aromatic additives showed a greater tendency to soot than their aliphatic counterparts. All the additives increased the total PAH and enol yields, with benzene yielding the highest. The halogenated form of benzene decreased the total PAH and enol yields when compared to benzene, suggesting that halogens accelerate the conversion of PAHs to soot. The effect of bromine in increasing the total PAH and enol yields is more than that of chlorine.
Download or read book Polycyclic Aromatic Hydrocarbons PAH and Soot Formation in Premixed Laminar N heptane Flames written by Fikret Inal and published by . This book was released on 1999 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Halogenated Aliphatic Olefinic Cyclic Aromatic and Aliphatic aromatic Hydrocarbons written by Wolfgang Felix Von Oettingen and published by . This book was released on 1955 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Halogenated Aliphatic Olefinic Cyclic Aromatic and Aliphatic aromatic Hydrocarbons written by Wolfgang Felix Von Oettingen and published by . This book was released on 1955 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Theoretical Modelling and Mechanistic Study of the Formation and Atmospheric Transformations of Polycyclic Aromatic Compounds and Carbonaceous Particles written by Antonius Indarto and published by Universal-Publishers. This book was released on 2010-06-11 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic Aromatic Hydrocarbons (PAHs) and soot share the same origin (incomplete combustion or pyrolysis) and nature, namely structural and electronic features. The purpose of the research work discussed in this thesis is to offer a theoretical contribution to elucidate some aspects of PAH and soot particle formation. The interest in carrying out such a work lies on one hand in the ubiquitous presence of both species in the environment, on the other hand on the concern for their impact on both human health, specifically involving the respiratory system, and climate, in particular as regards global warming. Thus, a better knowledge on the formation mechanisms of PAHs and soot could then help the efforts to reduce their concentration in our atmosphere. Since the formation mechanisms still presents unclear aspects, the suggestions and indications which can be offered by a theoretical study come out to be complementary to the large amount of experimental data collected so far. In setting up models aimed to mimic what happens in real pyrolysis or combustion situations, we have exploited the fact that PAHs and soot share as a common trait the presence of condensed unsaturated cycles (whose aromatic character can be variable). Thus, though types of soot of different origin will exhibit, on a larger scale, a variety of structural traits, we have chosen an assortment of PAH-like models to study different processes, together with other smaller unsaturated closed and open shell species that are known to play a role in the synthesis course. A preliminary phase of the study was aimed to assess which computational level could be both dependable and affordable to investigate the growth of a PAH-like radical when it is adsorbed onto soot platelets (particle phase). Then the Bittner-Howard variant of the widely accepted Hydrogen Abstraction Acetylene Addition (HACA) growth mechanism has been explored by Density Functional Theory (DFT) at the level mentioned above, both in the gas and particle phases, and over a wide range of temperatures. A parallel mechanism, differing from HACA, based on polyynes and characterized by the proliferation of radical centers, has also been studied for a variety of models at a multiconfigurational theory level. To the end, we have explored several reaction pathways starting from the addition of the propargyl radical to butadiyne.
Download or read book Polycyclic Aromatic Hydrocarbons written by and published by National Academies Press. This book was released on 1983-01-01 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Examination of Mechanisms and Fuel Molecular Effects on Soot Formation written by Meredith Colket (III.) and published by . This book was released on 1988 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: A variety of hydrocarbons has been pyrolyzed in a single-pulse shock tube over the temperature range of 1000 to 2400 K and for dwell times of 500 to 700 microseconds. Gas samples of reactant, intermediate, and final products were collected and analyzed using gas chromatography. Chemical kinetic models in good agreement with data were developed for several of the hydrocarbons that were pyrolyzed. Specific mechanisms and rate coefficients have been proposed in order to describe formation of aromatic hydrocarbons. These latter processes are believed to lead to the formation of polycyclic aromatic hydrocarbons, soot precursors, and eventually soot. The work has focused on the pyrolysis of acetylene, since this species appears to be the dominant species in soot-forming regions of flames and has been shown to play a major role in the soot-forming process. Keywords: Hydrocarbon pyrolysis, Oxidation, Acetylene, Ethylene, Vinylacetylene, Benzene, Formation of aromatics, Soot formation.
Download or read book Toxicology of Halogenated Hydrocarbons written by M.A.Q. Khan and published by Elsevier. This book was released on 2013-09-17 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: Toxicology of Halogenated Hydrocarbons: Health and Ecological Effects covers the papers of a symposium held at the 2nd Chemical Congress of the North American Continent and the 180th national meeting of the American Chemical Society in fall of 1980 in Las Vegas, Nevada, USA. The book contains papers on human exposure and health effects; hepatotoxicity and carcinogenicity; and cytotoxicity, teratogenicity, mutagenicity, and neurotoxicity. The text also presents papers on the metabolism and toxicodynamics of halogenated hydrocarbons, as well as the embryotoxicity and environmental fate related to halogenated hydrocarbons in animals and humans.
Download or read book The Carcinogenic Effects Of Polycyclic Aromatic Hydrocarbons written by Andreas Luch and published by World Scientific. This book was released on 2005-08-22 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an overview on the molecular mode of action of carcinogenic polycyclic aromatic hydrocarbons (PAHs). PAHs are by-products arising from incomplete combustion of organic matter that are frequently released into our environment, and thus are ubiquitously detectable. Many PAHs are strong carcinogens in rodent bioassays and have been linked to increased incidences of various types of cancer in humans. The present book covers all aspects of PAH-induced carcinogenesis; it is a collection of articles written by some of the most recognizable PAH researchers, reviewing the present knowledge in this field. The topics include: exposure to and biomonitoring of PAHs in the human population; metabolic activation of PAHs; genotoxicity and repair of PAH-induced DNA damage; and factors modulating individual susceptibility to the deleterious effects of PAHs.
Download or read book Modelling Interactions of Polycyclic Aromatic Hydrocarbons During Soot Formation written by Timothy Stephen Totton and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Halogenated Aliphatic Olefinic Cyclic Aromatic and Aliphatic Aromatic Hydrocarbons Including the Halogenated Insecticides Their Toxicity and Potential Dangers written by U.S. National Institute of Arthritis and Metabolic Diseases and published by . This book was released on 1967 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Polycyclic Aromatic Hydrocarbons in Soot written by R. J. Martin and published by . This book was released on 1974 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soot in Combustion Systems and Its Toxic Properties written by J. Lahaye and published by Springer. This book was released on 1983-06 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our interest in Mulhouse for carbon black and soot began some 30 years ago when J.B. Donnet developed the concept of surface chemistry of carbon and its involvement in interactions with gas, liquid and solid phases. In the late sixties, we began to study soot formation in pyrolytic systems and later on in flames. The idea of organ1z1ng a meeting on soot formation originated some four or five years ago, through discussions among Professor J.B. Howard, Dr. A. D'Alessio and ourselves. At that time the scientific community was becoming aware of the necessity to strictly control soot formation and emission. Being involved in the study of surface properties of carbon black as well as of formation of soot, we realized that the combustion community was not always fully aware of the progress made by the physical-chemists on carbon black. Reciprocally, the carbon specialists were often ignoring the research carried out on soot in flames. One objective of this workshop was to stimulate discussions between these two scientific communities. During the preparation of the meeting, and especially during the review process by the Material Science Committee of the Scientific Affairs Division of N.A.T.O. the toxicological aspect emerged as being an important component to be addressed during the workshop. To reflect these preoccupations we invited biologists, physical chemists and engineers, all leaders in their field. The final programme is a compromise of the different aspects of the subject and was divided in five sessions.
Download or read book Health Effects of Halogenated Aromatic Hydrocarbons written by William Jamieson Nicholson and published by . This book was released on 1979 with total page 730 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Toxicological Profile for Polycyclic Aromatic Hydrocarbons written by and published by . This book was released on 1995 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Polycyclic Aromatic Hydrocarbons written by Guilherme C. Bandeira and published by Nova Science Publishers. This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polycyclic aromatic hydrocarbons (PAHs) are high molecular weight, aromatic compounds containing two or more benzene rings joined together in different ways. They belong to a group of persistent organic pollutants (POPs); are resistant to degradation; and can remain in the environment for long periods with the potential to cause adverse environmental and health effects. This book discusses the chemistry, occurrence and health issues related to PAHs. Topics include PAHs in foods and herbal medicines; biomonitoring of PAHs by pine needles; thermodynamics and phase behavior of polycyclic aromatic hydrocarbons mixtures; occurrence of polycylic aromatic hydrocarbons in cephalopods; children environmentally exposed to PAHs and at risk of genotoxic effects; analysis of PAHs in environmental solid samples; the chemical and electronic properties of PAHs; and the determination of PAHs in drinking water sources.
Download or read book Polycyclic Aromatic Hydrocarbon PAH and Soot Formation in Premixed Flames written by Tyler Reed Melton and published by . This book was released on 2000 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
